Decorations applied to hot glass products. Glass goods

MINISTRY OF JUSTICE OF THE RUSSIA

Ryazan Institute of Law and Economics

Department of Production Management and Marketing at the Department of Internal Affairs

COURSE WORK

Topic: Glass and ceramic products

Introduction

2.3 Quality of glass and ceramic products

Conclusion

Application

Introduction

The glass and ceramics industry is currently undergoing major changes and is in the process of evolution. The industry is transitioning from producer to consumer. From now on, the consumer is free to change his purchasing pattern, no longer based on necessity, but on choice. Goods best quality we need to maintain sales levels and attract customers.

The most important characteristics and consumer properties of glass and ceramic products are considered by many scientific works and monographs of famous scientists and practitioners, such as Brilevsky O.A., Brozovsky D.I., Borisenko I.M., Burova M., Gamidullaev V.N., Ivanova E.V., Nikolaeva S.L., Ivanov A.I., Ivanov G.G., Kruglyakov G.N., Mikulovich L.S., Loktev A.V., Furs I.N., Pankratov V. .K., Seregina T.K., Penkov V.I. etc. However, issues of improving the quality and other properties of glass and ceramic products are not discussed in sufficient detail in the popular and specialized literature.

All of the above determined the choice of the topic of this course work and its main goal: to provide a large-scale analysis of the properties, range and quality of glass and ceramic products.

The set goal is achieved by solving the following tasks:

Give the concept of glass and ceramics and give their classifications;

Consider the consumer properties of glass and ceramic products and the factors of their formation;

Characterize the range and quality indicators of glass and ceramic products.

In the process of studying and processing materials, the following research methods were used: abstract-logical, monographic, economic-statistical, calculation-constructive, and basic analysis techniques were used. The theoretical basis of the study was made up of special literature on the problem under study by domestic authors.

The work consists of an introduction, two chapters and a conclusion; contains 29 pages of typewritten text, a list of sources used and a graphical appendix.

1 General characteristics of glass and ceramic products

1.1 Classification, composition and structure of glass and ceramics

The glassy state is a type of amorphous state. Solids in glassy form are called glass. Glass is characterized by hardness, uniformity, fragility, and transparency. Glass can contain almost all elements of the periodic table. Silicate glasses (a class of oxide glasses), in which silica serves as the glass-forming oxide, are widely used for the manufacture of tableware and decorative items. Silicate glasses are economical due to the abundance of raw materials, ease of industrial processing and a favorable combination of technological and consumer properties.

The production of glassy silica (quartz glass) is technologically very complex and requires high temperatures (1750-1900°C). Silicate glasses are multicomponent compositions in which, in addition to silica, there are oxides of alkali and alkaline earth metals, and sometimes compounds of other groups.

For household tableware, according to GOST 24315-80, glass of the following compositions is used: sodium-calcium-silicate, special household, crystal, low-lead crystal, lead crystal, high-lead crystal, barium crystal.

Typical compositions of soda-lime-silicate glass (in weight percent): SiO2-73-76, CaO-6-8, Na2O-12-15, Na2O-1-6. Special household glass (aluminosilicate, borosilicate) also contains magnesium oxides (2.76-8.0%), boron oxides (5-12%), which improve its mechanical and thermal properties. Crystal glasses contain oxides of lead and barium, which increase density, transparency, shine, and improve the play of light. Composition of lead crystal (in weight percent): SiO2-57.5, K2O-15.5, Na2O-1.0, B2O3-1.2, PbO-24.0, ZnO - 1.8. Low-lead crystal has less (18-24%) lead oxides, while high-lead crystal has more (30% or more).

Ceramic products are products made from clay mixed with mineral additives and fired to a stone-like state.

Ceramics are classified according to the nature of the structure, the degree of sintering (density) of the shard, types, types and varieties of the shard.

Based on the nature of the structure of the shard, a distinction is made between coarse and fine ceramics. Products of coarse ceramics (pottery, bricks, tiles) have a coarse-grained porous shard of heterogeneous structure, yellowish-brown in color. Fine ceramic products include products with a dense sintered or finely porous homogeneous structure, white or light-colored - porcelain, fine stone products, semi-porcelain, earthenware, majolica.

According to the degree of sintering (density) of the shard, ceramic products are divided into dense sintered with water absorption of less than 5% (porcelain, thin stone, semi-porcelain products) and porous with water absorption of more than 5% (faience, majolica, pottery).

The main types of ceramics are porcelain, fine stone products, semi-porcelain, faience, majolica, pottery ceramics. Porcelain is made in two types - hard and soft (characterizes not the physical hardness of the shard, but its composition and firing temperature)

A type of hard porcelain is low-temperature (low-sintering) porcelain. Soft porcelain also has several varieties. Our country produces mainly bone and high-feldspathic soft porcelain. Faience can also be hard or soft, but currently only hard faience is produced. Majolica is divided into the following types: from earthenware masses, white-burning clays, semi-porcelain masses and colored clays.

The type of ceramics and its properties are determined by the composition and structure of the shard and glaze, which in turn depend on the processing of the original raw materials, the composition of the masses and glazes, and the characteristics of the firing regime. The composition of ceramic masses includes plastic clay substances (clay and kaolin), waste materials (quartz, quartz sand), fluxes (feldspar, pegmatite, perlite, bone ash, etc.).

During the firing process, as a result of complex physical and chemical transformations of the components of the mass and the glaze charge, and their interaction, the structure of the ceramic shard and glaze is formed. The structure of the shard is heterogeneous and consists of crystalline, glassy and gas phases.

The crystalline phase includes mullite (3Al2O3×2SiO2), remains of altered clayey matter, and grains of undissolved quartz. The crystalline phase and especially mullite crystals increase the strength, heat resistance and chemical resistance of the shard.

The glassy phase is formed by melting flux, partly quartz and other components. In amounts up to 45-50%, it increases the strength of the shard; with a higher content, it reduces heat resistance and increases the fragility of products. This phase helps reduce water absorption and makes porcelain translucent.

The gas phase (closed and open pores reduces mechanical strength, thermal and chemical stability, and determines water absorption of the shard.

The ratio of individual phases in a shard, as well as the composition of each phase, the composition and structure of the glaze layer are specific to different types of ceramics. Below is a description of the composition and structure of the main types of ceramics.

Porcelain is a fine ceramic product with a dense sintered shard of white color with a bluish tint. The composition of hard porcelain includes 50% clay substances (mainly kaolin), 25% quartz and 25% feldspar. In the structure of a shard fired at 1380-1420 °C, the glassy phase makes up 40-60%, the crystalline phase up to 30-35 and the gas phase 5-7%. Therefore, the crock has a water absorption of no more than 0.2%, is translucent in a layer up to 2.5 mm thick, and is characterized by high mechanical, thermal and chemical resistance. When struck, it produces a clear sound. Porcelain is used to make tableware and artistic and decorative items.

Low-temperature porcelain contains an increased amount of flux with 50-55% clay substances. It is fired at 1200 °C, and forms a dense shard with water absorption of up to 0.5%, increased mechanical and thermal strength. This porcelain is usually glazed with a white opaque glaze; in a thin layer it does not show through. Used for the manufacture of tableware intended for catering establishments.

Soft bone china contains 53% flux (feldspar and bone ash), 32% clay substances and 15% quartz. It is fired at 1200 °C, up to 85% of the volume of the shard is the glassy phase. Bone china is distinguished by its high whiteness and translucency (up to 4 mm), but its strength and heat resistance are less than that of hard porcelain. It is used for the manufacture of highly artistic tea and coffee tableware and decorative items.

Soft feldspathic porcelain with a high content of feldspar is intended mainly for artistic and decorative products, in particular sculptures.

Thin stone products have a sintered, non-translucent shard painted in grayish, beige tones with a water absorption of 0.5-3%. It is used for household utensils and art products, some varieties of it are used for heat-resistant kitchen utensils.

Semi-porcelain is a fine ceramic product with a non-translucent white shard, with a porosity of 0.5-5%. It is covered with a colorless or colored glaze. Semi-porcelain is used to make tableware, teaware, food storage utensils, and some artistic and decorative items.

Faience is a fire-top ceramic product with a porous shard of white color with a yellowish tint. The mass contains 60-63% clayey substances and only 5-15% flux. In a faience shard fired at 1250-1280°C, the main phase is crystalline. The glassy phase (about 20% of the volume) is located between the structural elements of the shard and ensures their strong connection. The total porosity of the shard is 26-30%, open - 9-12%. Due to its significant porosity, faience has lower mechanical strength compared to porcelain and is prone to swelling. The lower thermal stability of faience is due to the high thermal expansion of the glaze, as well as its sharp difference in composition from the shard. Faience in a thin layer is not translucent, and when struck it emits dull sound. It is used mainly in the production of tableware.

Majolica is a fine ceramic product with white or colored non-transparent shards of varying density. Water absorption of majolica from earthenware masses is 12%, from white-burning and colored clays - up to 16%, from semi-porcelain masses - up to 5%. Majolica is covered with colorless or colored, transparent or dull glazes. It is usually decorated underglaze, often with a relief design. Used for art products and household utensils.

Pottery ceramics are coarse ceramic products with coarse-grained colored porous shards (water absorption 15-16%), partially or completely covered with fusible glazes. It is produced from pottery clays with the addition of waste materials.

1.2 Trends in the development of the glass and ceramics industry in Russia

In the article Ph.D. A.I. Elfimov, Advisor to the Ministry of Economy of Russia, Corresponding Member of the International Academy of Investment and Construction Economics, “Results of Industry Work” (“Production Expert”, 2002, No. 4 (47), p. 3) provides the following data on the production of glass and ceramic products ( Fig.1.1):

Fig.1.1. Dynamics of gross industrial output by industrial complexes in the period 1998-2001, as a percentage of the previous year

At the glass factories of Saratovsteklo JSC and Salavatsteklo JSC (Republic of Bashkortostan), the production of glass consumer goods and glass using modern “float technology” has increased. JSC "Kvartsit" (Bryansk region) did not resume work on glass production after major repairs. Due to lack of funding, new construction and reconstruction of glass enterprises in the Rostov, Vladimir regions, Krasnodar Territory, and the republics of Bashkortostan and Dagestan have been stopped."

Flat glass production capacities, concentrated at 17 Russian enterprises, allow the production of 167 million sq.m. glass per year.

Float glass production capacities are concentrated mainly in three largest enterprises:

JSC "Bor Glass Factory" - 25 million sq. m. per year;

JSC "Salavatsteklo" - 22 million sq.m. per year (2 technological lines);

JSC "Saratovsteklo" - 39 million sq.m. per year (6 technological lines).

The product range of Salavatsteklo JSC includes: consumer glass goods, automotive glass, automotive and construction triplex, as well as electrochemically colored (light-protective), metallized and multilayer safety glass.

The Progress enterprise (Saratov) produces reflective (sun-protective) glass using film coatings in a volume of 1 million square meters. m and double-glazed windows - 0.5 million sq. m.

The production of tempered glass in Russia is underdeveloped. The main manufacturers are Bor Glass Factory, Saratovsteklo, Salavatsteklo. In the Moscow region there are only two glass manufacturers with lines with a total capacity of 387 sq. m. m per hour. World practice shows that in a developed market, one glass tempering line with a capacity of 200 sq. m per hour should account for approximately one million inhabitants. This means that for Moscow alone (without the region) a minimum of 8 such lines are needed.

The needs of the Moscow region are estimated at a total of 32 million square meters of glass. It was noted that in the Moscow region and 16 bordering regions there is not a single production facility that produces glass using float technology. At the same time, about 200 manufacturers of double-glazed windows out of 600 in Russia as a whole are concentrated in Moscow and the Moscow region.

In Solnechnogorsk (Moscow region), the BAMO-Stroymaterialy company continues to build a plant for the production of float glass. The planned capacity of the enterprise is 18 million sq.m of float glass and 2 million sq.m of double-glazed windows per year.

Ceramic products from the Konakovo faience factory named after M.I. Kalinin (Kalinin region) occupies one of the leading places due to the high quality of workmanship and beautiful external decoration, with pronounced national features.

The traditions of the ancient folk craft of porcelain products are currently continued by the masters of the Leningrad State Porcelain Factory named after M.V. Lomonosov. This enterprise specializes in the production of unique and highly artistic porcelain products, the bulk of which are of a souvenir and gift nature. Over the past 15 years, their number has increased more than 8 times. The production of products with cobalt glaze and underglaze painting has been mastered. In addition to the usual mass of hard porcelain, the plant has developed new compositions of porcelain masses that ensure the production of porcelain of high whiteness and translucency - bone china (its composition includes up to 50% of ground animal bone meal). Artistic porcelain is produced mainly by casting. Complex products in their raw form are assembled from several parts; sometimes hand modeling is used. All operations are carried out very precisely; The finishing of the products is particularly thorough. The plant is equipped with modern equipment, many production processes are automated and mechanized.

The Sysert art porcelain factory in the Sverdlovsk region is a young enterprise. It was created on the basis of the Promkooperator artel, organized in 1942. The factory produces porcelain products.

The Kungur plant "Ceramic" in the Perm region is a relatively young enterprise. The first batches of ceramics at this arts and crafts enterprise appeared in 1962. Recently, its products have become increasingly popular.

Bogashevsky Experimental Plant of Artistic Ceramics was created in the early 70s of the 20th century. The discovery of large deposits of white clay in the vicinity of Tomsk served as the production basis for its creation. The company's product range includes utilitarian household items made of porcelain and earthenware: mugs ("Tomsk", "Yubileinaya"), jugs, drinking sets, dumpling sets, pancake, tea, children's ("Cheburashka" etc.), industrial and building ceramic products.

2 Analysis of the main consumer properties, range and quality indicators of household products made of glass and ceramics

2.1 Consumer properties of glass and ceramic products

Ergonomic:

These properties are taken into account when developing and putting products into production, certification, as well as in regulatory and technical documentation.

The nature of blown glassware decorations is very diverse.

Decorations applied while hot are combined into several groups. The first group includes decorations based on obtaining an optical effect or surface relief. These are “roller” decorations, corrugations, small bubbles, “frost” (“crackle”). The “bullet” is blown in a rough form with indentations or protrusions. When blown in a fine (smooth) form, the optical effect of a wave-like surface (“roller”) or recesses filled with air (air ribbons, threads, bubbles) is created. “Frost” (“crackle”) is a decoration in the form of a network of melted cracks, reminiscent of frosty patterns on glass. To obtain it, a set of glass is dipped in cold water or wet sawdust for 1-2 seconds, and then heated in an oven. After processing in this way three times and subsequent blowing, the product acquires a “frost” pattern.

Rice. 2.1. Decoration methods glassware

1 - matte tape; 2 - engraving; 3,4,5 - diamond dust: 6-guilloche etching

The second group includes jewelry with ornaments. They are obtained by introducing a glass blank of one color into a semi-finished product or finished product of a different color. These are colored threads, stripes, stains, scorch marks, crumbs, fiberglass decorations, watercolor stains, colored overlays. Blanks of softened colored glass in the form of threads, cords, pieces or openwork fiberglass are applied to the “bullet” using various techniques. After molding, decorations are obtained in the form of twisted or tangled threads, stripes, spots, and lace patterns. Colored coatings are applied to the finished product in the form of a large sculptural relief (a softened blank of colored or colorless glass is applied). The image of the emblem is obtained using a stamp. To apply colored chips, the “bullet” is processed on a metal tile strewn with finely ground glass.

For highly artistic products, more complex decorations are used: mosaic, filigree, foreign inclusions of other materials.

The third group of decorations is the application of a rainbow film to the surface of the product by the deposition of iridescent substances (irrization). The product is treated in a special chamber with vapors of tin chloride, strontium nitrate, and barium chloride. Depending on the ratio of these compounds, temperature and exposure time, the effect of a colorless film with a blue or reddish tint is created.

The consumer properties of ceramic products are determined by the properties of the ceramics, as well as the shape and design of the products. Let us consider the most important physical and chemical properties of ceramics.

Porosity (open) is characterized by water absorption of the shard. It varies from 0.2% for hard porcelain to 16% for majolica. As it increases, strength and heat resistance decrease. Porosity may be the reason why the shard is permeable to water.

The mechanical strength of ceramics determines the durability of products. During compression it is quite high, and during tension, bending and especially impact it is 10 or more times lower than during compression. Thus, the compressive strength of hard porcelain is 450-550 MPa, tensile strength is 40, and impact strength is 0.1-0.22 MPa. The hardness of the glaze of hard porcelain is 7 units of the mineralogical scale, earthenware - 6, majolica - 5. With increasing hardness, abrasion resistance increases, and the smoothness and shine of the glazed surface is maintained longer.

Thermal stability is characterized by the temperature difference between heated and cooled samples, at which through cracks in porcelain and glaze cracks in earthenware products appeared. The heat resistance of porcelain dishes is at least 165 ° C, earthenware - 145, majolica - 100-110 ° C. Like mechanical strength, heat resistance determines the purpose and durability of products.

The chemical resistance of glazes and overglaze decoration determines the hygiene and preservation of the surface of the glaze and decorative coatings when exposed to water, food acids, and alkalis. Depends mainly on the chemical composition. Feldspathic porcelain glazes are characterized by the highest stability, while high-alkaline and lead-containing majolica glazes are less stable.

Whiteness is an important indicator of the aesthetic properties of porcelain and earthenware products. Depends mainly on the content of coloring oxides (Fe2O3, TiO2, etc.) in raw materials and ceramic masses. For hard porcelain it is 55-68%, for bone porcelain - 74-80%.

Translucency is inherent only in hard (with the exception of low-temperature) and soft porcelain. Depends on the amount of glassy phase in the structure, porosity. The translucency of a 2 mm thick hard porcelain shard is 0.09-0.15%, while that of soft porcelain is much higher. In practice, it is usually determined visually.

The gloss of the glaze depends on its composition and the condition of the surface. Majolica and earthenware glazes containing compounds of high-density elements (barium, strontium, zinc, lead) have increased gloss. Glaze defects - pinholes, pockmarks, bald spots - sharply reduce shine.

Ergonomic properties include hygiene and ease of use of the product. Hygiene is characterized by the release of harmful substances (compounds of lead, zinc, cadmium, etc.), ease of use - an indicator of the correspondence of the mass of the product to the strength capabilities of a person, its design - the size and shape of a person’s hand. Ergonomic indicators also include the permissible angle of inclination of the product before the lid falls out, the indicator of drainage ability, as well as the roughness parameter of the unglazed parts of the product. Usability indicators are usually assessed by expert method in points.

The aesthetic properties of tableware are characterized by whiteness, translucency, shine of the glazed surface, perfection of shape, decor and their compliance modern style, the integrity of the composition, as well as the perfection of production execution of products.

The consumer properties of ceramic goods are formed at the design and construction stage when creating a prototype (author's) sample and during the production process. The prototype must be suitable for its intended purpose and meet modern requirements ease of use, reliability, beauty. It must be reproduced as accurately as possible in mass or serial production. The quality of reproduction of the prototype and the perfection of product manufacturing are ensured by compliance with the established production technology.

2.2 Range of glass and ceramic products

According to their purpose, glass products are divided into groups: tableware and decorative items for table setting and interior decoration (Appendix 1); kitchen utensils for cooking; household utensils for food storage and home canning (Appendix 2).

Based on the composition of the glass, dishes are distinguished from sodium-calcium-silicate, crystal, and special household glass.

Depending on the color, the dishes can be made of clear, colored or applied glass. Products made of colored glass are painted throughout the entire mass of glass; products with a thickened bottom or with a flooded bottom have a painted bottom. Products made from applied glass are characterized by the presence of two, less often three, layers of glass. Each layer appears in individual details of the design when applying the decoration.

According to the molding method, dishes are distinguished between blown, pressed, press-blow, multi-stage production and bending.

Products are divided according to style, taking into account the shape of the body, bottom, edge, and attached parts. Based on the shape of the body (vessel), products are distinguished in the form of a ball (hemisphere), cylinder, cone, ellipse, bell, basket with handle, horn (glasses). Combinations of individual elements of the form are possible, as well as the presence of constrictions along the body when dividing the form. Depending on the nature of the bottom, products can be without a filler or with a filler bottom, on a pallet or without it. The edge of the products is smooth, cut-out, figured. The shape of the adhesive parts is determined by the configuration of the legs and handles. The leg of the products can be straight (cylindrical), funnel-shaped, figured (with transitions, for example, a flat ball, with an oval thickening, etc.), according to the processing method - polished and unpolished. The style of products is also determined by the design of detachable body parts (plugs, caps, etc.).

The size of the product is divided depending on the shape, capacity and linear parameters into small, medium, large, extra large.

According to the method of decoration, dishes are distinguished between smooth and decorated (Appendix 3). Among the decorated ones, free-blown products are distinguished from other types of (semi-mechanized and mechanized) decorations.

The method of application, nature, labor intensity, artistic merits of jewelry, and the presence of national elements determine the division of the assortment into group and non-group. Group (mass assortment) products are divided into cutting groups according to the nature and complexity of decorations: from colorless glass - from 1st to 7th; colored glass from 3rd to 8th; overlay glass - from 4th to 8th. Group crystal products, distinguished by more complex decorations, are from the 4th to the 10th cutting group (Appendix 6).

Non-group products reflect the national characteristics of the assortment, the creative style of the artist, artistic features compositional means of decorating branded products, characteristic of individual factories.

Pressed crystal products come with a pattern from the shape and with partial modification of the edges. Pressed products are not divided into cutting groups.

According to the method of heat treatment, the dishes are not hardened, i.e. conventional annealed products, and hardened by hardening. Hardening is used for dishes that experience sudden temperature changes during use (tea dishes, some types of tableware, kitchen utensils). The products are heated to a temperature close to softening, and then quickly cooled in a stream of cold air. In this case, stresses are evenly distributed throughout the thickness of the product, as a result of which its mechanical strength and thermal stability increase.

Signs of the type of product are operating conditions and style. The range of types of glassware is represented by 66 nomenclature subgroups, which include a large number of varieties of products according to various characteristics.

The completeness of products is determined by their purpose and the generality of the artistic and constructive solution. Complete products are represented by devices for various purposes: for water, wine, dessert, cups, kvass, milk, compote, jam, smoking, toilet, etc.

The range of tableware for table setting includes the following nomenclature subgroups: glasses, goblets, shot glasses, wine glasses; decanters, jugs, milk jugs, cream jugs; glasses, mugs, cups; vases for table setting (for sweets, fruits, cream, jam, salad, menazhnitsa, crackers, sugar bowls); dishes, plates, saucers, trays; salt shakers, oil dishes, etc.

Decorative items are represented by flower vases, goblets, horn-shaped glasses, powder compacts, etc.

Kitchen utensils must have high mechanical properties and thermal stability. Its traditional range is represented by products made from special household glass (heat-resistant borosilicate glass). Increased mechanical and thermal properties of products are determined by a high content of boron oxides (up to 12%) and special heat treatment-hardening. The dishes are hygienic and easy to clean, but they are not durable enough. New in the development of the range of kitchenware is the use of glass ceramics.

Sitall is a glass-crystalline material obtained by the directional crystallization of glasses of special compositions. Sitalls have a microcrystalline structure. In terms of chemical composition, heat-resistant glass ceramics belong to the spodumene system with TiO2 additives as a crystallization initiator. Ceramic glassware has increased strength and heat resistance (up to 500 °C), and can withstand repeated sudden temperature changes. Hot dishes can be immersed in cold water, and cooled ones can be placed on the open flame of a gas burner. The dishes are white, reminiscent of glazed porcelain, and decorated with paints.

Glass and ceramic glassware are molded by pressing. Its nomenclature includes seven items: saucepans, braziers, baking dishes, frying pans, stewpans, duck pots, compote makers. These products are predominantly oval in shape, have a lid and rounded handles. Their disadvantage is their increased weight.

Household utensils are produced from special household glass by press blowing. The glass composition includes 3-3.5% MgO and 3-4% Al2Oz. Household utensils are made from bleached and semi-white glass containing 0.05-0.5% Fe2O3. The range of these dishes includes mainly wide-necked products: for storing food products - barrels, bottles for pickles, jars for honey, jam; for canning - jars, bottles. The capacity of the dishes is from 750 to 8000 cm3. Utensils for canning are produced by thermally strengthening by the hardening method.

The most promising direction for the development of the assortment of tableware and decorative products is its continuous updating and expansion by increasing the artistic level of mass products, individualizing the products of individual factories (branded products), and creating highly artistic products for mass production. Much attention is focusing on expanding the range of products made from colored and crystal glass. The assortment of mechanized tea and tableware with increased mechanical strength (hardening) will become significantly more diverse.

The range of household ceramic products is grouped according to the following main characteristics: type of ceramics, purpose, type of product, style, size, types and complexity of decoration, completeness. All these features determine the price of the product.

Based on the type of ceramics, a distinction is made between porcelain, fine-stone, semi-porcelain, earthenware, and majolica products.

Depending on the purpose, there are dishes for catering establishments and products for household use. The range of tableware for catering establishments is in the process of being formed. Products must be strictly functional, versatile, convenient for mechanized washing and storage. The main material for their manufacture is low-temperature porcelain, semi-porcelain.

The assortment of household products made from all types of ceramics is divided into tableware (tea, coffee, tableware, etc.) (Appendix 4) and artistic and decorative products (sculpture, flower and decorative vases, etc.) (Appendix 5).

The types (names) of dishes are varied. The names of products are often associated with their purpose (kettle, oil dish, sugar bowl, etc.).

The style of the cookware is determined by the shape of the body (round, oval, multifaceted, etc.), design (on a leg, on a tray, with handles, with a lid), the nature of the surface (smooth, with a relief pattern), edge treatment (smooth, carved) , the nature of the side (solid, openwork). The outlines of the body and details of dishes for special occasions are more complex. Products can be on a leg, with a cut-out edge, a relief surface, or an openwork border. The style may have a name (“Radiant”, “Bud”, etc.) or a number.

By size, porcelain and earthenware products are divided as follows: small - with a diameter or length of up to 175 mm, with a capacity of up to 250 cm3 inclusive; medium-diameter or length from 175 to 250 mm, capacity from 250 to 600 cm3 inclusive; Large - with a diameter or length of 250 mm or more, with a capacity of 600 cm3 or more.

According to the types of cuttings, dishes decorated with printing, stencils, decals, paintings, etc. are distinguished. Cuttings of porcelain and earthenware dishes and, accordingly, products are divided into group and non-group. Group cutting of porcelain products according to complexity is divided into 10 groups - from 1st to 10th, earthenware - into 7 groups - from 1st to 7th. Cutting pottery from other types of ceramics is not divided into groups. The styles and designs of non-group products are unique. Out-of-group products are considered highly artistic; The price list provides an individual description of them.

Based on completeness, they distinguish between piece (single), paired (cup and saucer) and complete dishes in the form of cutlery, sets, gift and other sets, sets and sets. Most items are included in sets, which are a collection of services, sets or sets united by a single style solution. Dinnerware, tea, and coffee sets contain mandatory types of utensils for a specific number of people. Sets are a collection of one type of tableware, for example, sets of plates of different sizes. Sets - several types of tableware for one purpose, for example, a gift set of a cup with a saucer and a plate. The devices are a set or set for individual use.

Artistic and decorative items are made from all types of ceramics. These can be unique (author's), small-scale and mass-produced products. They are divided into decorative sculptures (busts, human figures, animals, birds), wall plates, dishes and bas-reliefs, decorative vases and utilitarian art products - flower vases, decanters and utensils for wine and liquor, glasses, powder boxes, ashtrays and etc. The nomenclature, shape, and decoration of artistic products are specific to each manufacturer.

Let us consider the features of the range of fine ceramic products made from various types of ceramics.

Porcelain. The range of these products is the most diverse. The trade includes tableware made from hard, including low-temperature and soft bone china, as well as artistic and decorative items.

The range of tea and coffee tableware made of hard porcelain is presented in the price list in the following main types: tea cups with saucers (200-500 cm3), coffee cups (60-130 cm3), mugs (90-500 cm3), glasses (375-600 cm3) , glasses (200-250 cm3), bowls (140-400 cm3), teapots (250-1000 cm3), top-up teapots (up to 5000 cm3), coffee pots (500-1400 cm3), butter dishes (100-400 cm3), creamers (150-425 cm3), milk jugs, sugar bowls, vases for fruit and jam, saucers for jam, crackers, rinsers.

The range of tableware includes small plates (150, 175, 200, 240 mm in diameter), deep plates (200 and 240 mm in diameter), bowls (170-220 mm), round and oval dishes (300-450 mm), herring bowls ( length 135-300 mm), vases for soup or compote (capacity 2000-3500 cm3), gravy jugs with or without a tray, salad bowls, menu bowls, sprat bowls, products for spices - salt shakers, mustard pots, pepper shakers, horseradish bowls, vinegar bowls.

Tea and tableware for children (pieces and sets) are small in size, simple, convenient in shape. Its decor is very unique - images of animals, birds, fairy tales.

Other utensils include napkin holders, jars for bulk products, sour cream bowls, pots for curdled milk, etc.

Complete products are represented by sets (tea, coffee, tea-coffee, dining) for 6 and 12 people, sets, cutlery and fittings. Thin-walled non-group tea and coffee sets have high aesthetic merits. Thin-walled sets with expanded configurations are now available for sale.

Artistic and decorative products of various types are made from hard and soft porcelain, from white and colored masses, glazed, unglazed, linen or painted.

Fine stone products and semi-porcelain products. Their range is still limited. They produce individual items of tableware and teaware, sets, as well as barrels for storing food. Heat-resistant kitchen utensils are produced from heat-resistant fine stone masses. Products are decorated with colored glaze, underglaze or overglaze cuts. Artistic and decorative items - flower vases, wall decorations, flowerpots, ashtrays.

Earthenware products. They are represented mainly by tableware, since their shards, compared to porcelain, are less heat-resistant, rougher, and non-translucent. The assortment of tableware includes the same types of products as the assortment of porcelain, and, in addition, platinums and bread bins. About 70% of the assortment of earthenware products are plates of different sizes. Cups, teapots, and jam vases are not made from earthenware. The shape of the products is most often round or oval, with a soft transition from one part to another. Cuttings - group and non-group, mainly underglaze. They produce table sets and sets, coffee sets. The range of artistic and decorative products is small.

Majolica products. The assortment of majolica is determined by the area of ​​production, types of shards, purpose and other characteristics. The range of majolica products made from earthenware includes single-piece and complete tableware and art products. The assortment of majolica dishes made from semi-porcelain masses, white-burning and colored clays, along with tea, coffee and tableware, includes dishes for cooking and heating food (on a divider or in the oven).

Artistic majolica products are very diverse and are represented by sculpture (usually animal figures), flower vases and decorative (table, wall, floor, hanging), wall decorations, souvenirs, and various products of a utilitarian nature. Majolica products are decorated with single-color and drip glazes, crackle and fire-reducing glazes, engobes painting, etc.

In the structure of the range of fine ceramic products, porcelain products make up 64-65%, earthenware - 31-32, majolica - 2%. About 70% of the production of porcelain and earthenware falls on the share of plates and cups and saucers, which cannot be considered optimal. The degree of renewal of the assortment of tableware annually is 24-25%.

The main directions of development of the range of fine-ceramic products: development of specialized tableware for various types of public catering establishments, expansion of the range of personal use products for the kitchen (refrigerator containers, food jars, mortars, etc.), increasing specific gravity complete tableware in the total output up to 30%, optimization of the composition of complete tableware for everyday use, increasing the production of highly artistic products, including sets, extended sets, as well as souvenir and gift items.

2.3 Quality of glass products and ceramics

Glass products perform not only a utilitarian function, they are also a decorative element of the interior. In the design process of these products, factors that determine their consumer properties must be taken into account. The quality of new products when they are put into production, as well as products submitted for certification, is assessed according to indicators of functional, ergonomic, aesthetic, technological, patent-legal, environmental properties and reliability.

Products must be stable on a horizontal plane, the edges of the top edge, the surface of the bottom of the products, the neck, stem and end of the stem of the cork of decanters must be ground and polished; cutting edges of the products are not allowed. Matte finishing of the neck and stopper of decanters of the 1st, 2nd, 3rd groups of cuts is allowed. Details of the drawings made different ways, must be clear and carefully worked out.

Based on their appearance, crystal products are divided into two grades. Products made from sodium-calcium-silicate glass, special household glass, as well as pressed crystal glass without modification are not divided into grades.

For products certified for the State Quality Mark, artistic and aesthetic indicators (presentation, shape, decor, quality of workmanship, quality of glass) are standardized. They must have a score above 27 points.

Requirements for dimensions (capacity or linear measurements) are given in the corresponding tables, permissible deviations are indicated in the standards. Industry standards standardize physical and technical indicators.

The quality of annealing is characterized by residual stresses determined on a polariscope-polarimeter device; they should not impair the performance properties of products. The degree of hardening for hardened products is established by the quantitative characteristics of the difference in the stroke and the categories of glass according to birefringence, measured on the same device.

Products must be thermally stable: withstand tests for temperature differences of 20-95-70-20 ° C for annealed teaware; 20-135-15°C - for tempered cookware. At least 99% of products must pass the test.

For products made of lead, barium and other types of crystal, standards have been established for the refractive index of 1.545-1.520.

To control the quality of products in commercial practice, non-destructive methods are used.

The quality of ceramic products is standardized by state and industry standards and specifications.

The regulatory and technical documentation regulates a number of physical and technical indicators and design features that determine the consumer properties of products - overall dimensions, container capacity, crock thickness, mechanical strength, water absorption, whiteness and translucency (for porcelain), etc.

The dishes must be durable. Plates and saucers made of hard porcelain should not be destroyed when stored for 5 days in stacks of 120 pieces, from thin-walled bone china, as well as earthenware - 100 pieces each. Attached parts (handles, spouts) must withstand a load that is twice the weight of water filling the product.

The heat resistance of porcelain dishes should be 165°C, earthenware products with colorless glaze - 145, with colored glaze - 115, majolica dishes - 100-110°C.

The water absorption of porcelain crockery is 0.2%, thin-walled crockery is 0.1%, earthenware is 12%, majolica crockery is 5-16% depending on the density of the crockery.

The whiteness of dishes made of hard porcelain of the highest quality category must be at least 68%, 1st grade - 63, 2nd grade - 55%.

Whiteness standards for thin-walled dishes, as well as bone china, are higher. For all other types of ceramics, whiteness is not regulated quantitatively.

Porcelain dishes should be translucent in layers of no more than 2.5 mm, in bone china products - 3-4 mm.

The surface of utensils that come into contact with food must be acid-resistant.

Majolica containers for liquids must be waterproof. To check the water resistance of these products, place them on a sheet of white paper and fill them with water; after 24 hours there should be no wet spot on the paper or sweat on the walls.

Ceramic products in shape, design, size, decoration, and completeness must correspond to the standard samples. The dishes must have the correct shape and be stable on a horizontal plane. Parts (handles, spouts) should be located symmetrically. The drain hole should ensure that liquid pours out of the dish in an undivided parabolic stream. The color shades of the parts must match the shade of the body. It is required that the lids of teapots and coffee pots have a tight fit and do not fall out when the product is tilted 70° (lids with a high hinge or a lock - 80°); the glaze was continuous, uniform in thickness; the unglazed edges of the product are ground and polished, and the legs are sanded.

If the technological regime is violated, product defects may occur. Defects such as double-sided through cracks, unpolished or unglazed gouges or nicks, cracks in the glaze, bubbles (blowing of a shard or glaze 4 mm or more in size), peeling of paint are not allowed. Products with these defects are rejected.

Depending on the appearance, physical and technical characteristics, size and number of defects, all fine ceramic dishes, with the exception of fine stone and majolica made from colored clays, are divided into products of the highest category and 1st, 2nd, 3rd grade. Fine stone and majolica products from colored clays are produced in two grades - 1st and 2nd.

Art products are of the highest category of quality and 1st and 2nd grades, except for products of the Leningrad Porcelain Factory named after M.V. Lomonosov, for which there are four grades - highest, 1st, 2nd, 3rd.

2.4 Labeling, packaging, acceptance, transportation and storage of products

During the marking process, a label is affixed to the non-front side of each product using water-soluble glue that is neutral to protective and reflective coatings, indicating:

Name and/or symbol;

Identification of this standard and/or specifications;

Month and year of manufacture.

Each package is affixed with a label indicating:

Name and/or trademark of the manufacturer;

Amount in a package.

Each product must be wrapped in wrapping paper or placed in plastic or paper bags. Products of the same name and one container are placed in wooden boxes, corrugated cardboard boxes, cardboard boxes or paper bags lined with soft materials, weighing no more than 30 kg. The packaging must ensure the safety of the products during transportation. The type of packaging may change upon agreement with the consumer.

Packaged products are placed in universal containers, boxes or special containers in accordance with regulatory and design documentation approved in the prescribed manner.

The space between the products and the walls of the container or box must be filled with wood shavings, corrugated cardboard or other sealing materials in accordance with regulatory documentation approved in the prescribed manner.

A label is placed on each container or box indicating:

Name and/or trademark of the manufacturer;

Name and/or symbol of the product;

Number of products;

Designation of the standard and/or technical specifications;

Packing date;

Number or surname of the packer.

By agreement between the manufacturer and the consumer, the following is allowed:

Indicate additional information in the marking, as well as use another method of marking that does not affect the quality of the products;

Use other types of packaging and shipping containers that ensure the safety of products during transportation and storage.

Each batch of products is accompanied by a quality document, which indicates:

Name and/or trademark of the manufacturer;

Name and/or symbol of products;

Number of products;

Number of boxes or containers, pcs.;

Acceptance mark (technical control stamp);

Number and date of document preparation;

Identification of the standard and/or technical specifications.

When accepting goods for quality from different places, a batch of 1% is selected, but not less than 10 products of each size and grade. They check the conformity of the products to the standard sample, the presence, size and location of defects, and the correctness of the grade. If necessary, determine physical and technical parameters. Check the content and clarity of the labeling data, the method and condition of the packaging.

Products are transported by any type of transport in accordance with the Rules for the carriage of goods in force for this type of transport, placement and fastening in vehicles - in accordance with the “Technical conditions for loading and securing goods” approved by the Ministry of Railways.

When transporting, containers or boxes with glass and ceramic products must be secured so as to prevent them from moving and swinging during transportation.

When transporting, loading and unloading glass and ceramic products, their safety from mechanical damage and precipitation must be ensured.

During transportation, container boxes are covered with metal tape and sealed. Cardboard boxes are covered with paper tape, paper bags are tied with twine.

Boxes, cardboard boxes and paper bags are marked indicating: the name of the manufacturer and its location, trademark, names of products, number of products in packaging, designation of standard, article, grade, price, release date, quality control stamp.

A handling sign meaning “Caution, fragile” is applied to the packaging and transport containers.

They transport artistic ceramic products and souvenirs by any type of transport with proper protection from mechanical damage and precipitation in accordance with the transportation rules in force for this type of transport.

Products made of glass and ceramics should be stored in a dry, closed area. Direct exposure to sunlight is not allowed. When accepting, placing and releasing glass and ceramic products, special care must be taken, as these are fragile and easily breakable goods. When storing large glass and ceramic products, they should be placed on the lower shelves, medium and small ones - on the upper ones.

Conclusion

Thus, glass and ceramics are irreplaceable materials on which many aspects of human cultural life depend.

Glass products entering trade must be characterized by a set of properties that ensure their demand and consumption. According to GOST 4.75-82, consumer properties of cookware include the following groups:

Properties that determine the purpose of the product - stability on a flat surface, glass density, functional suitability, dimensions, capacity;

Reliability - durability, impact strength, thermal stability, preservation of the product and coating under the influence of water, abrasion, light:

Ergonomic:

Aesthetic - compliance of a serial product with a standard sample, perfection of forms, decor, production execution, compositional integrity, play of light, transparency;

Economic - cost of the product.

The consumer properties of ceramic products include functional, ergonomic, reliability, and aesthetic (GOST 4.69-81 “Porcelain and earthenware tableware. Nomenclature of indicators”).

The functional properties of products are their shape and size, stability on a flat surface, heat resistance, and ability to absorb water.

Ergonomic properties include hygiene and ease of use of the product.

Reliability is characterized by the resistance of products to bending, impact, resistance of attached parts to tearing, the strength of the glazed surface and decorative coating to abrasion, their acid and alkali resistance.

Aesthetic properties.

The basis for constructing an assortment of household glass products is based on the following characteristics: purpose and operating conditions, chemical composition and glass coloring, molding method, style and size, decoration method and complexity, heat treatment method, type, completeness of the product.

The quality of glassware is regulated by industry standards: OST 21-4-77 “Tableware and decorative glassware” and OST 21-35-77 “Dishware and decorative glassware.”

Requirements for the quality of glassware are standardized in terms of appearance, physical, technical and size indicators. The appearance of products is determined by the quality of the glass melt, the quality of workmanship, the nature, quantity, severity and location of defects. In terms of shape, manufacturing method, nature of processing and decoration, the product must correspond to the approved standard sample and technical description.

The normative and technical documentation for ceramic products regulates a number of physical and technical indicators and design features that determine the consumer properties of products - overall dimensions, container capacity, crock thickness, mechanical strength, water absorption, whiteness and translucency (for porcelain), etc.

List of sources used

1. Civil Code of the Russian Federation.

2. Law Russian Federation"On the protection of consumer rights dated February 7, 1992 No. 2300-1 (as amended by Federal Laws dated January 9, 1996 No. 2-FZ, dated December 17, 1999 No. 212-FZ).

3. Law of the Russian Federation “On the Protection of Consumer Rights dated February 7, 1992 No. 2300-1 (as amended by Federal Laws dated January 9, 1996 N 2-FZ, dated December 17, 1999 N 212-FZ).

4. Law of the Russian Federation “On Standardization” dated June 10, 1993 N 5154-1 (as amended by Federal Law dated December 27, 1995 N 211-FZ).

5. Law of the Russian Federation “On certification of products and services” dated 06/10/93 No. 5151-1 (as amended by the Federal Law dated 12/27/95 No. 211-FZ, dated 03/02/98 No. 30-FZ dated 07/31/98 No. 154-FZ).

6. Law of the Russian Federation “On the quality and safety of food products” dated January 2, 2000 N 29-FZ.

7. Instructions on the procedure for accepting production and technical products and consumer goods by quantity (as amended by the Resolutions of the USSR State Arbitration Court dated December 29, 1973 N 81, dated November 14, 1974 N 98).

8. Instructions on the procedure for accepting products for industrial and technical purposes and consumer goods for quality (as amended by the Resolutions of the USSR State Arbitration Court of December 29, 1973 N 81, of November 14, 1974 N 98)

9. Decree of the Government of the Russian Federation "On the labeling of goods and products on the territory of the Russian Federation with marks of conformity protected from counterfeiting" dated 05.17.97 No. 601 (as amended by Decree of the Government of the Russian Federation dated 19.09.97 No. 1193, dated 20.10. 98, No. 1223, dated 06/24/99, No. 685, dated 07/10/99, No. 787).

10. Decree of the Government of the Russian Federation “On some measures aimed at improving systems for ensuring the quality of products and services” dated February 2, 1998 N 113.

11. Resolution of the State Standard of the Russian Federation “On the Rules for the Application of the Mark of Conformity for Mandatory Certification of Products” dated July 25, 1996 No. 14 (as amended by the Resolution of the State Standard of the Russian Federation dated October 20, 1999 No. 54).

12. Rules for the sale of certain types of food and non-food products. Approved by the Decree of the Government of the Russian Federation. January 19, 1998 No. 55.

13. GOST 4.69-81 “Porcelain and earthenware tableware. Nomenclature of indicators".

14. OST 21-4-77 “Dishes and decorative glassware.”

15. OST 21-35-77 “Dishes and decorative items made of crystal.”

16. GOST 111-90 Sheet glass. Technical conditions.

17. GOST 5533-86 Patterned sheet glass. Technical conditions.

18. GOST 7481-78 Reinforced sheet glass. Technical conditions.

19. GOST 25535-82 Glass products. Methods for determining thermal resistance.

20. Brilevsky O.A. Merchandising of non-food products. - M.: March, 2001. - 614 p.

21. Brozovsky D.I., Borisenko I.M. Fundamentals of merchandising. – M.: “Economy”, 1988. – 351 p.

22. Burova M. Commodity research of non-food products. Lecture notes. - M.: PRIOR, 2000. - 144 p.

23. Gamidullaev V. N., Ivanova E. V., Nikolaeva S. L. Commodity research and examination of non-food products: Textbook. - M., 2001. - 628 p.

24. Ivanov A.I. Seller's Guide. - M., 2002. - 134 p.

25. Ivanov G.G. Commodity research and examination of non-food products. - M.: Mossovet, 1994. - 406 p.

26. Kruglyakov G.N. etc. Commodity research of non-food products. - M.: March, 1999. - 448 p.

27. Mikulovich L.S., Loktev A.V., Furs I.N. and others. Merchandising of non-food products: Textbook for universities /Under the general editorship. Brilevsky O.A. - M., 2001. - 248 p.

28. Pankratov V.K., Seregina T.K. Commercial activity. Textbook M.: ICT “Marketing”, 1997. - 422 p.

29. Penkov V.I. Metrology, standardization, certification and quality management. - M., 1997. - 334 p.

30. Entrepreneur's Directory: retail trade, wholesale trade, freight transport, catering and hotel management. - M.: Nauka, 1994. - 770c.

31. Theoretical basis commercial merchandising of non-food products: Textbook / Oryol State Technical University. - M., 1995. - 166 p.

Application

Decorative tableware for table setting

Example of kitchen glassware for cooking

Smooth and decorated dishes

WATERFORD makes not only vases and glasses from crystal, but also cutlery handles
The characteristic elongated transition from the stem to the bowl of the glass is a distinctive feature of VILLEROY BOCH crystal Frosted pattern and thick crystal in the home collection from CHRISTOFLE SEGUSTO VIRO
Interglass gilding: on the island of Murano they use very thin plates of gold, breaking up into myriads of stars The matting technique (sand processing) is also used by WATERFORD SEGUSTO VIRO
Mosaic glass is made by fusing colored pieces of glass melt.
FORMIA
"Aquarium" vases. First, fish and water scenery are made, and then they are melted inside a transparent mold. IITTALA glass is fused from thin spiral threads Humor is the main feature of RITZENHOFF design
IITTALA birds "hatch" every year and are never repeated
The company KOSTA BODA likes to use fantasies on the theme of Matisse in paintings
SEGUSTO VIRO
Murano glass. In this case, the vases are decorated with fused threads of colored glass
LEONARDO is not interested in straight lines; designers are keen on playing with smooth curves
Ice glass KOSTA BODA. Nowadays, this manufacturing technique is becoming increasingly rare. FORMIA
Vases from FORMIA are fused from pieces of colored mass Pisces is the typical and most popular motif of Murano glass
DEMAGLASS glasses are sold in sets of three and are united by one theme Since Art Deco, LALIQUE has loved to depict animals. Corporate style of glasses from RITZENHOFF

Glass was invented in Ancient Egypt, most likely by accident. The first glass mass found by archaeologists dates back to the Bronze Age. Today, three main types of glass melt are used, more than five technologies for the production of products from it and about twenty techniques for external finishing.

They don't make anything out of glass! Remember the beautiful glasses and wine glasses from the Gus-Khrustalny factory, which until recently adorned all sideboards without exception? And Bohemian glass in gold, green and red colors is a source of pride for any housewife! But glassmakers do not stop there, and our market is being conquered by more and more foreign brands of glass and crystal. So how can you understand their diversity? And in general, what kind of brands are these? You may find the answer in this article.

Production technology

Glass, which is familiar to us, is obtained by fusing quartz with oxides of various metals. The main component of the glass mass is silicon dioxide. It is obtained from quartz sand. Previously, lime or chalk was added to the glass melt, which made the glass durable, thin and shiny. Nowadays this technology is rarely used. The addition of potash or soda produces clean and light glass, which, due to its refractoriness, is primarily suitable for molding. Crystal was first produced in the 17th century in England. To achieve this, lead was added to the glass mass. Crystal differs from ordinary glass in its stronger shine and high refractive index of light, due to which it plays with all the colors of the rainbow. It is durable and can be cut.

To color (tint) the glass mass, metal oxides are added to it during melting. For example, iron will make a transparent material bluish green or yellow, manganese yellow or brown, chromium grass green, uranium yellowish green (called uranium glass), cobalt blue (cobalt glass), colloidal silver yellow, copper - red. There are also types of glass such as bone and milk glass. The first is obtained by clouding the glass melt with burnt bone, the second is made with the addition of a mixture of feldspar and fluorspar. And if you stir up the glass melt to a very weak degree with the same spar, you get opal glass

.

The technology for making glass and crystal has remained virtually unchanged over the centuries. The oldest product, cast glass, is produced, as before, using two forms, external and internal. The gap between them is filled with glass melt, and then the product is fired in a kiln.

Free glass blowing was used in Ancient Rome already in 75-50 BC. e. The blowing tube is dipped into the glass mass melted in the furnace. Then, after removing the tube from the oven, they roll out the mass on a stone or metal surface, giving it a cylindrical shape. By rotating the product on the tube rod, the neck of the vessel is blown out. At the end of the process, the rod is beaten off, and the chip is then polished.

Blowing glass into molds became widespread in the 18th and 19th centuries. In this technology, the product is given preliminary shapes using a tube, and then it is placed in a mold made of wood or iron, cooled and processed. Free-blown or mold-blown glass can be easily identified by the mark left by the tube.

Pressed glass was first made in the 20s of the 19th century in America, from where it spread to Europe. This was a fundamentally new method of processing glass melt, in which it was poured into a copper or iron mold and pressed using a blank. This technique, with some individual additions and improvements, was used by Rene Lalique and Galen.

Types of glassware finishing

There are many known techniques for interior and exterior decoration of glass objects. Let's focus on the most interesting and spectacular ones.

“Glass yarn” technique: a glass thread of a different color or transparency is wound onto a pre-prepared glass mold. The patterns of this thread can be different and form a grid (reticell glass), combed threads (feather effect) or opal spirals (filigree). On the island of Murano in Venice, another modification of this technique was developed - millefiori ("thousand flowers"). Small glass plates or tubes are melted into the glass surface to form flowers (hence the name). In this case, transparent bubbles are blown into the material using thin hollow needles (like a syringe), and transparent sparkling threads are formed by air pumped into the glass mass in a special way.

Ice glass (craqueled, or crackle) is produced by immersing the workpiece in cold water, causing a network of random cracks (craquelure) to form on the surface. The glass is then reheated and blown.

Creating laminated glass requires a very experienced craftsman. The blown blank is either dipped alternately into several multi-colored glass masses, or covered with colored layers on the inside. Then the layers are sanded, etched or made openwork, similar to a cameo.

Mosaic glass: The casting mold is filled with small pieces of multi-colored glass. Then the mold is placed in the oven and the pieces are fused.

The most common type of exterior decoration for glassware is painting. It can be produced by the cold method (opaque paints are applied to the surface without subsequent firing) and fired enamel (colored glass enamel forms a transparent layer on the surface of the product, contrasting with the main background).

The glaze is made using only two metals - silver (which produces a yellow glaze) and copper (which produces a black or red glaze).

The iridescence technique gives the glass a pearlescent shine. The color ranges from transparent white to red-gold. The famous TIFFANY art glass is made using this technique.

Gold is one of the most popular means of decorating dishes. Thin foil can be fused between layers of glass (interglass gilding, popular in Bohemia) or cover the outside. It is also possible to paint the surface with gold oxide (this is cheaper than foil, so it is especially popular).

Etching or satin finishing (this technology is used to process LALIQUE crystal) began to be used in 1771 with the discovery of hydrofluoric acid. This acid itself makes the glass shiny, and its gases make it dull. You can etch the entire surface (while it remains smooth and silky) or selectively (only the drawing).

The entire surface or just the design can be treated with a stream of fine-grained sand - a matting technique. The same effect is obtained as with acid etching, but the plane becomes rough and coarse-grained.

Crystal can be engraved and cut. The engraving is applied to the surface using a diamond. The patterns appear as if scratched and shallow. Conventional cutting is performed using sharp diamond cutters and special grinding wheels. This produces a pattern deeply recessed into the surface. Diamond cut: diamond-shaped pyramids stand out on the surface.

Sanding is used to create round and olive-shaped depressions in the surface. The technique of fusing glass threads, droplets or circles of transparent and colored glass makes a smooth surface textured.

So, we got to know how and what glass is made of and how it can be decorated. Now it's time to get acquainted with the products of modern glass blowers. Of course, there are a lot of companies producing glass and crystal dishes; it is impossible to talk about them all in one short article. So we will limit ourselves to only the most famous foreign designer brands.

To everyone and everyone

Let's start the review with what is available to everyone - mass production. The technology of its production is mechanized as much as possible, but even here it is impossible to do without manual labor. Sketches of form and decor are made by designers. Next, the products are made using a stencil or template, which makes them relatively cheap without depriving them of aesthetic value.

The first brand you need to pay attention to is IITTALA (Finland). IITTALA glass is produced using a special technology with the addition of lime. The dishes are transparent, thin, but very resistant and not subject to mechanical damage. It tolerates washing in the dishwasher very well.

Finnish design is valued all over the world, and IITTALA is typical of this country. Minimalism and the style of the 1950s-1970s have become the hallmarks of the IITTALA brand. Her collections include pieces of "classic" design, developed in the 1950s to 1970s. But the assortment is poorly replenished with products from modern designers. Artists from Finland, Sweden, and Germany work for this manufacturer. Glasses, decanters, vases, and candlesticks are distinguished by their simplicity and laconic forms and minimalist decor. There are no drawings, the products are monochromatic, colorless or muted shades of gray, white, black, brown, blue, green, red. Prices range from $5 (small glasses) to $100 (large decanters and vases). If you want to give a gift, you can use the IITTALA Pro Arte collections, which include vases, plates, sculpture, original plastic, handmade using mosaic, laminated, icy glass and decorated with “glass yarn”, glaze and glass fusions. These items cost a little more, but are still affordable - from $50 (vase).

DEMAGLASS and CHURCHILL (UK) are kindred spirits: they are created to help turn an ordinary meal into an enjoyable one without spending too much money. In the DEMAGLASS collections, you should pay attention to the glasses, which are sold in convenient packages of three pieces. Cocktail glasses from the latest collection are decorated with a ruler for measuring the amount of ingredients needed. There is also fashionable Japan - bamboo thickets, hieroglyphs, dragonflies. DEMAGLASS works with both clear glass and sand-treated glass.

CHURCHILL glass - mostly frosted, with a stenciled floral design. We offer both individual flowers and entire flower fields or bouquets - from gerbera to chamomile, from rose to violet. It is very easy to choose a whole set of dishes in the same style (glasses of different sizes, decanters, bottles, etc.). Decor options for glasses and decanters change every year. The prices for products of these two brands are approximately the same: 3 glasses - from $20.

Utilitarian, beautiful and inexpensive glass is also produced by such companies as NEMTOI (Italy), LUMINARC and ARCOROC (France), DARTINGTON CRYSTAL (Great Britain).

Many designers are not afraid to be present in every home and do not strive to be super exclusive. On the contrary, their goal is universal accessibility. And at the same time, they are able to impart dazzling humor to even such a simple object as, say, a champagne flute. Original forms charm with their simplicity or captivate with their light madness. The works of such masters are inexpensive; buying even a whole set for a table will not blow your budget. And at the same time, a special style, beauty, and humor will penetrate into the house. First of all, these designers are counting on young people, easy-going and not afraid of experiments. But they also know how to please representatives of the older generation, adding a little spice to the strict classics. We are referring primarily to such designer brands as LEONARDO (Germany), RITZENHOFF (Germany) and KOSTA BODA (Sweden).

Inexpensive designer items

The first German company in our review is LEONARDO, which has been working with glass for a long time and very successfully. The main thing is not to confuse it with other companies that in one way or another play on the name of the great Leonardo da Vinci in their names. The German manufacturer we are talking about supplies its products with a blue label with white clouds and the inscription LEONARDO. The technology of cast glass, despite its simplicity, does not make objects of this brand less valuable, but only allows them to be produced in large enough quantities so that the work of the craftsmen is not valued too expensively. Most of all, LEONARDO loves colorless glass and playing with shapes. The company's collections include items for the table, for gifts and simply for decorating a room. LEONARDO prefers modern design, avant-garde and minimalism and is not afraid of pop art style. Often, shocking aesthetes, he uses the images of Santa Claus and Mickey Mouse. And at the same time, she strives to make her objects as functional as possible, so often the same vase or bowl can serve different purposes. There are practically no straight lines in the design; they are curved, refracted, and bent.

LEONARDO attaches great importance to the decoration of its products. Clean smooth surfaces are used quite widely. If the item is nevertheless decorated, then the most common motifs are Zen hieroglyphs, geometric shapes, as well as jungles with predators and snakes. Colored products “scare” with their wild color. The color is unbridled, bright, far from ordinary - grass, coal, mouse, scarlet, azure, violet, milky, even metallic. The order of prices is as follows: glasses and glasses - $12, plates - $20, vases - $38.

And yet, in the field of decoration, LEONARDO is just a child compared to RITZENHOFF. This manufacturer produces glasses, tumblers, shot glasses, ashtrays, cups of classic, familiar shapes, but their design cannot be called ordinary. Every year the company holds a competition among designers and artists and selects those who will “make the difference” in the near future. RITZENHOFF glass is completely ordinary, produced by casting. But the drawing is applied by hand, often by the artists themselves who made the sketches. The style of the drawings is varied: caricature, pop art, primitivism, avant-garde. The main distinguishing feature of RITZENHOFF decor is humor and original idea. Each designer's collection contains from 100 to 500 items and is produced one-time, without repetition. All items are sold in packaging made by the same artist, with a certificate of authenticity, the creator's autograph and a story about what the design means. Some collections come with a unique napkin or stand. But, despite the fact that RITZENHOFF glass is a collectible and an ideal gift, its prices are low. For example, a milk glass in a custom designer box costs about $30.

The Swedish company KOSTA BODA, like all northerners, is distinguished by its hidden temperament. He uses glass that is quite difficult to manufacture: there are objects made of cobalt, crystal, and crackle (with an ice effect). The manufacturing technology is casting, the number of copies of one type is up to 1000. Collections are produced one-time, but for several years you can order the item you like at the factory. One of the exterior finishing options is coating with real silver sheets with a worn, patina effect. This is the company's signature technique. KOSTA BODA offers collections of vases, tableware, gifts and watches. For gifts, a unique technology of laminated glass is used: the product is painted when cut, then a layer of colorless glass is fused, then color again, and so on ad infinitum. The result is a frontally transparent object, and when you look at it from an angle, a color is revealed inside, and what kind of color it is. And of course, constant primitivism - glass painting in the style of Matisse. Each product has signatures of designers and artists. Prices are pleasantly affordable: silver glasses start at $35 each, large cobalt vases start at $60.

A triumph of aesthetes

Now let's talk about the collections of famous manufacturers who mainly produce items for the table. Of course, this is not just a table setting, but a classic style and consistent quality, a symbol of prosperity and respectability. And yet, this category includes not only exceptional things that are used only at weddings or anniversaries, but also more modest and affordable ones.

Let's start the story about glass for aesthetes with the French brand CHRISTOFLE. In fact, she is primarily known for her silverware, but she also does not do without crystal (crystal, not glass). At CHRISTOFLE you will find everything you need to “drink beautifully”. A subject of special pride is a variety of glasses, shot glasses, glasses, decanters, created specifically for different types of drinks (from wine to beer). CHRISTOFLE crystal is made by hand and is very pleasant to the touch. The surface is engraved and then etched, giving the engraved design a matte finish. The company's know-how is special silver and silver plating, the recipe of which is kept secret. Silver is present in spectacular crystal objects for special occasions (stems of glasses, handles of decanters, painting). Despite the fact that the brand is characterized by classic design without extravagance, French glassmakers are constantly coming up with something new. In the upcoming collection, silver and gold will be present in the design of vodka glasses. Moreover, this is not simple foil or painting, but a special technology of internal spraying. The cost of crystal glasses without silver is from $50.

The WATERFORD brand from Ireland is more democratic. We offer both a complete set for drinking and eating, as well as items for home decoration (vases, photo frames, figurines), plus collections for special occasions (wedding, anniversary, New Year). A distinctive feature of WATERFORD is the technology of adding silicon oxide to the glass mass, which makes the crystal soft and pliable. This made it possible to create the famous diamond cut (not to be confused with engraving). The surface of the crystal is textured, as if covered with protruding diamonds. The company divides its collections according to age rather than property: adults are offered expensive, heavy, thick-walled cut crystal, while young people are offered light and thin crystal with engraving. Products “for adults” are made exclusively by hand - from blowing to cutting; crystal “for young people” is technologically simpler, cast. The shapes and decorations of the “adult” collection are conservative and classic (deep and diamond cuts), while the “young” collection is more avant-garde and laconic in form and decoration - grinding, engraving, cutting of individual elements (legs, handles) are used. WATERFORD is the favorite brand of US presidents; inaugural feasts are held only with this crystal. It can be seen in movies, and is used to make sports cups and awards. Despite this, the cost of glasses from the “adult” collection is from $40, and from the “young” collection – from $15.

For people who want to decorate not only the table, but the entire house in a classic style, we can recommend VILLEROY BOCH. The initial specialization of the company is table porcelain. This company arose in the 19th century and was an indispensable companion of the richest and noblest people in Europe, including members of royal families. But time demands change. To win minds completely, the company also began producing crystal, as well as a variety of items for the table (from napkin rings to the napkins themselves), and, more recently, items for the bedroom and bathroom. VILLEROY BOCH crystal is lightweight, with a minimum lead content, but with the addition (to enhance shine) of silver and soda. An acid-etched pattern is used as decoration. The shapes of the glasses are classic; the famous brand prefers conservatism, adheres to strict taste and monitors the impeccable quality of its products. VILLEROY BOCH products can be distinguished by the smooth transition from the stem to the glass and the diamond cut of the pre-glass ball. Despite such frightening words as “conservatism” and “royal court,” VILLEROY BOCH crystal does not frighten at all with its prices - a glass costs from $40.

It is also impossible not to pay attention to the BACCARAT brand (France) and, of course, to individual glass and crystal products from various designers (designer glass), which have been increasingly appearing on the Russian market lately.

On the island of Murano in Venice there are many factories that produce inexpensive souvenir items, which are often brought to us under the guise of exclusive Murano glass and sold at crazy prices. To avoid becoming a victim of fraud, you need to know that only a few factories on the island produce exclusive glass. Murano glass cannot be confused with any other glass; it is pure, heavy, colored with metal oxides using complex techniques of threads, mosaics, millefiori or gilding.

Real art

There are few glass and crystal products in the world that can be elevated to the rank of art. These are exclusive items, made by hand, individually, equipped with certificates, signatures and numbers. The prices for such items have no limit, but a small thing can be purchased by a person with average income. Glass and crystal works of art will make the interior incomparable and will definitely be the center of attention. The brands that will be described below are also represented in our country, but buying abroad will be cheaper and there will be more choice. In addition, an exquisite little thing will become a pleasant reminder of the trip. Murano glass, as something completely special and unlike any other, should be devoted to a separate article. Here we will look at just a few of its brands, which, in our opinion, deserve the closest attention.

Let's start with the company FORMIA. You will find her products in almost all gift shops in Russia, but beware of fakes. The price of FORMIA glass is low (although in our country it is sometimes inflated to the point of indecency), and the level of skill of glass blowers is simply exceptional. All types of interior and exterior decoration mentioned in this article can be found in these items. And if you add the designers’ flight of fancy to the delights of Murano glass, you will get a work of art that you won’t be ashamed to give or bring as a souvenir. The company's specialty is a variety of figurines: fish, horses, funny people.

And now about the famous Murano artists. The SEGUSO VIRO company decorates products with color, threads, and magnificent inter-glass gilding. Moreover, the thinnest foil crumbles into tiny grains in the vessels, creating the effect of a golden haze. Designer Gianpaolo Seguso, a representative of the Seguso dynasty of glassblowers who founded their business in 1397, likes to combine different types of glass - cobalt, gilded, transparent, mosaic. All works of the master are signed, numbered and provided with a certificate. The SEGUSO VIRO collection includes vases, decorative plates, sculpture, and small plastic art.

The last two companies do not deal with table items, their work is decorations and gifts. I would like to finish this article about designer glass and crystal with a short story about the LALIQUE brand (France). The artist René Lalique founded the jewelry company that bears his name in 1885. Later the maestro became interested in glass. To make its crystal, the company has developed a special glass mass containing silver. Unlike other brands, LALIQUE blows and processes glass only while it is hot, and the cooling process can take more than 200 hours. All items are handmade in the factory and pass through 30 hands of master glassblowers, glass cutters, etc., before ending up in the store window. All crystal is carefully selected; only 20% of the produced products go on sale. The crystal is processed using the satin coating technique (exposure to hydrofluoric acid). This technique gives it a unique deep glow. LALIQUE collections include figurines, vases, plates, glasses and wine decanters. Perfume bottles, produced in limited quantities and almost never repeated, have long been an object of admiration. An absolutely unique collection of crystal jewelry - necklaces, rings, earrings. But still, the main direction of the company is vases and small plastic items.

LALIQUE uses sketches by contemporary artists, as well as sketches from the beginning of the century - by René Lalique himself and his masters. Typical motifs are animal and vegetable world, female figures and angels, stylized in Art Nouveau and Art Deco. LALIQUE branded showrooms, which present new collections and classics of the brand, can be found all over the world. Owners of items from LALIQUE can be sure that they have in their hands true treasures that will never lose their value.

Colored artistic crystal is also produced by DAUM (France) and the Murano Island factories ZANETTI and GAMBARO POGGI.

The editors would like to thank the companies HERMITAGE S.A., GEN-LEX ASSOCIATION, IITALA FINLAND, SIEGER DESIGN, VENEZIA salon, TWELVE Trading House, MBTM for their assistance in preparing the material.

Glass processing operations. Publishing house is divided into thermal. and technical

TO thermal ways samples of glassware relative. their annealing and hardening.

When heated glass is rapidly cooled, its outer layers cool faster than the inner layers due to the poor thermal conductivity of the glass. In materials that conduct heat well, the outer and inner layers practically cool down. simultaneous, therefore the difference in temperature between them is practically absent.

As a result of uneven cooling of the inner and outer layers in the glass, it arose. compressive and tensile stresses. When the cooling process ends and the temperature of the different layers of glass equalizes, the stresses that arose during the cooling moment either remain (these are residual stresses) or disappear (these are temporary stresses).

Temporary stresses of significant magnitude cause immediate destruction of the product, which means that residual stresses can cause both immediate destruction of the product and its destruction after a certain time.

The faster the cooling rate and the thicker (more massive) the product, the more significant the temperature difference between the different layers of the product will be and the more residual stresses will arise in the product.

The process of thermal processing, with residual stresses in the glass. items are weakened to a standard that ensures its long-term and reliable operation, called annealing . Annealing consists of heating products to a practical temperature. the beginning of softening and very slow cooling.

Operation hardening consists of heating the product to a certain temperature at which it is frozen. from the type of glass and the shape of the product, and rapid cooling according to the definition. regime. As a result, significant internal stresses are distributed evenly in the product and counteract the mechanical forces exerted on the product. loads

To technical processing related: breaking off the cap or its oxygen cut in blown products, grinding and heating the edges, fire polishing of products, grinding stoppers to the necks of decanters, etc.

After chipping off the cap, the edge of the blown product remains sharp, so it is polished on wheels using fine-grained sand as an abrasive material. For thin-walled products, the edges are heated under the action of gas burners. Under high temperatures, the glass softens, and due to surface tension forces, the edges are rounded.

Fire polishing of the surface is most often used. for pressed publications, on surfaces, m.b. various defects caused by contact of glass melt with the walls of the mold during the molding process. As a result, the appearance will improve. the type of product, and its strength will increase.

27. Decorating glass products

Glass due to its optics. sv - transparency and brilliance, phenomenon. scrap material with high artistic merit. To increase the level of aesthetics. St. glass The publishing house under their production uses various methods of decoration, which are traditionally called. "cuttings".

Decorations on the product can be applied directly during the molding process (in a hot state) and/or on the finished product (in a cold state). Glass products without cutting are called products “in satin finish” or simply “in satin finish”.

Decorations applied to products while hot. Colored glass products obtained by adding various dyes to the glass batch. These products are most often smooth, without additional cuts. The color of glass depends on its composition and dye concentration.

Products "with color" - This is multilayer (usually double-layer) glass. In this case, the inner layer of glass is usually colorless, and the outer layer is made of colored glass.

Decorations “marbled” and “malachite” in appearance. These stones remind me of them. Accordingly, this is muted glass with multi-colored threads, spots and green glass with veins of darker glass. These cuts are obtained by covering the workpiece with colored chips or by molding the product from pre-mixed unevenly mixed glass melt. colors with the addition of colored glass.

The “crackle” cut, which looks like a network of cracks in the thickness of the glass, is obtained by immersing the workpiece in cold water, as a result of which it becomes covered with a network of small cracks.

The decoration “decorative bubbles” is applied by sprinkling the workpiece with a mixture, after which it is blown into the final form.

“Colored ribbon and colored thread” decorations are obtained by wrapping a colored glass thread around the workpiece.

By rolling the workpiece over broken colored glass, “colored spots” are obtained. This is roughly the same way you get decoration in bulk. In this case, the molded product is rolled over colored glass chips, which adhere to it.

Roller decoration is obtained by blowing the product into a mold with a wavy surface.

The “optical pattern” cut is applied in two stages. First, the billet is blown in a rough mold, which is used by them. longitudinal edges, and then the product is blown into a finished mold with smooth walls. As a result, a product with a smooth outer surface appears faceted.

Decorations with luster paints received. by applying organic matter to the surface. combination of metals in organic. dissolve with subsequent firing.

In addition to the listed cuts, decorations such as attachments, cuts with fiberglass and fiberglass, iridescence, etc. can be applied in a hot state.

Glassware- depending on the purpose, it is divided into dining (varietal) and household.

Tableware(varietal) has a wide variety of assortment; grouped according to the following characteristics: production method, types, styles, sizes and nature of glass. According to the production method, tableware is divided into blown, pressed and press-blow.

Types of tableware are very diverse: glasses, saucers, decanters, shot glasses, goblets, goblets, jugs, milk jugs, sugar bowls, oil dishes, vases, salad bowls, crackers, teapots, cheese caps, ashtrays, toiletries, jugs, water utensils, liqueur and etc. All types of tableware (glasses, wine glasses, goblets, jugs, milk jugs, teapots, liqueur, crock, water and some other products) are produced using the blowing method, the shape of which excludes the possibility of using pressing. By pressing methods - products whose upper diameter is larger than the lower and middle (ashtrays, herring containers, beer mugs, stands for knives and forks, saucers, glasses, glasses, plates, etc.).

The styles of tableware are very diverse; they are determined by the design of the product and the shape of the body; By design they can be with or without a handle, without a leg or on a leg, etc., and by the shape of the body - spherical, oval, conical, etc.

The dimensions of the dishes are determined by the capacity of the products (glasses, decanters, jugs, etc.), diameter (plates, dishes and other flat products), height (flower vases), top diameter and height (vases for fruit, cookies, cream and jam). According to the nature of the glass, dishes are made from ordinary colorless glass, colored glass, colored glass, and crystal glass (colorless, colored, and colored).

Types of cutting glassware

Household dishesIts product range includes jars and barrels for pickles, jars for jam and milk, jars, jars, bottles, thermoses and flasks for home-canned foods, siphons, etc. This group also includes heat-resistant kitchen utensils manufactured made of special glass, usually transparent or having a slightly greenish-yellowish tint. Thanks to special hardening, this cookware has high thermal stability. It can be placed directly on electric stoves or in the microwave, subject to certain precautions (gradual inclusion of gas) - on gas stoves. It includes: cast-rules, frying pans, braziers, so-called ducklings, baking dishes, teapots, coffee pots, milk jugs, mugs, glasses, cups with saucers, plates, dishes, sauces, etc.

For the production of glassware, potassium-sodium-lime glass (the so-called ordinary glass) and potassium-lead (crystal) glass are usually used - Glass.

Tableware is made in two main ways: blowing and pressing.

Cutting glassware with diamond cut

Blowing utensils mainly (with the exception of tea glasses) produced manually using a blowing tube (a metal tube with a rubber reservoir - balloon); Glass melt is collected at the end of the tube, which, under the pressure of injected air, turns into a thick-walled bubble called a “jar.” Using various techniques, the “jar” is transformed into a so-called “bullet”, with such a distribution of glass as is necessary for blowing the finished product. The “bullet” is placed in a special mold and inflated under the pressure of blown air, the glass mass is pressed against the walls of the mold, taking on its outline, and in this form it freezes. If products have handles and legs (shot glasses, jugs, etc.), then the latter are made separately and then, in a softened state, attached to the body of the product. Machine blowing carried out on various types of machines. Thus, in the USSR, glasses were produced on VS-24 machines, decanters - on LVM machines, glass jars - on LAM machines.

Machines in which the “bullet” is produced by pressing and the product by blowing are called press-blow machines. Such machines include, in particular, the LVM machine.

Pressing carried out on manual, semi-automatic and automatic presses; it is much more productive than blowing. During pressing, the glass melt is fed into special molds. Under the influence of the core descending into the mold ( punch) glass melt fills the space between the walls of the mold and the punch and takes the shape of the product. All products are annealed in special furnaces: kept for several minutes at a temperature of about 500° and then slowly cooled. Annealing reduces residual stresses to an acceptable value. Unannealed or poorly annealed glass products will crack with minor temperature changes and slight shocks.

Glassware processing consists of separating the cap, processing the edge, and sometimes the bottom. To separate the cap on the body of the product, a line is made with a diamond and then a sharp flame of a gas burner is directed at this line. The cap then bounces off. The resulting uneven edge of the product is ground and then polished or melted with the flame of gas burners. The bottom of the products is first ground and then polished.

Glassware decoration produced in various ways. The main ways to decorate blown glassware during the blowing process are: inflated, marbled, with colored threads, with a wavy surface (roller), iridescence, etc. Dishes with inflorescence have two or more layers of glass, of which one is usually colorless. In dishes decorated with marble, between two layers of glass, one of which is milky and the other colorless, there are pieces of colored glass interspersed. For dishes with colored threads, the latter are either in the thickness of the glass or on the surface. Dishes decorated with a roller have vague longitudinal edges of varying widths on the body, while those decorated with iridescence have rainbow tints. Recently, the glass industry has been using a new method of decorating tableware, called “sulfide” glass. It consists in introducing zinc sulfide into the glass mass, which partially decomposes during the manufacture of tableware to form iron sulfides, which color the glass in a variety of colors.

Decoration of finished dishes (after processing) is done in various ways: matte tape, decorative grinding, engraving, etching, painting, gilding, decalcomania, photography, etc.

Matte tape- the simplest pattern resulting from processing a rotating product using a metal plate with sand and water. Decorative grinding is achieved using rotating carbon-rundium wheels that remove, or rather cut through, the top layer of glass and form edges of various shapes and depths.

Depending on the nature and complexity of these edges, grinding is divided into: simple or gross (in the form of round or oval pits); number plate with more complex designs; lettered or washer (wide edges); a diamond cut in the form of various deep slits (most often triangular in shape), forming patterns consisting of beams of rays, meshes, rhombuses, polyhedra, stars, etc. The diamond cut is distinguished by a variety of patterns and is divided into 10 groups according to complexity. The diamond cut is especially widely used for decorating crystal products, which are usually made with thick walls. The diamond edge clearly reveals the nature of the glass material and gives the products a greater play of light (color refraction).

Decorating glassware with a diamond cut (first difficulty group)

Engraving It is produced using rotating small copper discs and a special grinding paste. It can be matte or shiny - polished. Engraving produces designs mainly of a plant nature (flowers, leaves, berries, etc.).

Etching based on the property of hydrofluoric acid to dissolve glass. Depending on the complexity and depth of the drawing, the following are distinguished: types of etching: simple, or guilloche, pantographic- with a more complex pattern (both names come from the name of the machines with which patterns are drawn on products coated with waxy mastic) and deep artistic, performed mainly on products with color.

Painting on dishes is done with a brush using special silicate paints, fixed to the products by additional firing. Picturesque designs are most often applied to products made of colored glass or glass with color, predominantly milky white.

Painting products with gold, decorating them with decalcomania and the photographic method, which was previously used only in ceramic production, is widespread ().

Depending on the nature and complexity of the decoration, blown glassware is divided into complexity groups from No. 1 to No. 7, and thick-walled crystal - from No. 5 to No. 10.

Pressed dishes, as a rule, are not subject to additional decoration, since the design on them is obtained during the manufacturing process. A small part of pressed products is decorated by matting individual parts of the design (matting can be chemical or sandblasting), as well as grinding, polishing and gilding.

Decorating glassware with a diamond cut (second difficulty group)

Quality requirements and sorting. The quality of glassware depends on the rationality of the design of the product, which determines the ease of use; on the shape of the product, which affects its artistic value; on the quality of raw materials; the manufacturing and finishing process, which influences the appearance of the product and its operational properties - thermal, mechanical resistance, etc.

The use of low quality glass and violations of production technology cause the formation of a number of defects on products.

Glassware defects

Glass melt defects

1. Violation of colorlessness, resulting in different shades in the glass. Blurred shades (pinkish, bluish) are allowed.

2. Stone - foreign inclusions in the glass (particles of refractories or charge) sharply reduce the heat resistance of the glass. Not allowed.

3. Schlier - clumps of glass in the form of tubercles, usually having wavy branches.

4. Svil, which is wavy stripes in glass.

5. A bubble, which is gaseous inclusions in glass, transparent and cloudy (alkaline bubble), over 0.8 mm in size.

6. Midge - small bubbles, up to 0.8 mm in diameter.

7. Rukh, which is crystallized opaque glass particles.

Production defects

1. Uneven distribution of glass melt, resulting in a noticeable difference in the thickness of the walls and bottom of the products.

2. Blowout of the walls of the product - a sharp decrease in wall thickness in certain places.

3. Ovality of the body, bottom and tray, which violates the correct shape of the product.

4. Scale, which is the result of inclusion of iron particles from the blowing tubes.

5. Asymmetrical fastening of parts - violation of the symmetry of handles, legs, etc.

6. Curvature of the product - violation of the correct shape of the product.

7. Shcherbiny - depressions along the edge of the product.

8. Edge fraying is a small pitting of the edge of the product.

9. Chips - damage to the integrity of the side walls of products at the edge.

10. Cuts - small hairline cracks on products.

11. Scratching and scratches - stripes from scratching the walls of products with hard objects.

12. Gaps between the body and the cover.

13. Excess - burrs from the seams of the mold.

14. Underpressing - violation of the shape of pressed products; is the result of a lack of glass melt.

Processing defects

1. Traces of distillation (fine grinding).

2. Re-melting of the edge - curved inward and heavily melted edges of thin-walled products.

3. Skewed edges - violations of the correctness of the design, in which gaps and breaks in the matte tape and etched designs are noticeable, asymmetrical patterns, collapse of edges, blots, bulges, moles and burnouts in the picturesque cuts.

Decorating glassware with a diamond cut (third group of difficulty)

Based on the presence of these defects, blown and pressed crystal glassware in the USSR was divided into 1st, 2nd and 3rd grades; blown tableware and heat-resistant glassware - 1st and 2nd grade. Pressed tableware and household tableware made of ordinary glass were not divided into types. When establishing the grade, the type of defect, its size, location (on the body or at the bottom of the product), the method of making the dishes, the size and, in some cases, the nature of the decoration of the product, were taken into account.

There are a number of general requirements for glass tableware. The main ones are: correct shape and stability of products. The lid of sugar bowls, oil dishes, vases, jugs and other products must be selected according to style and color and fit tightly (without gaps) to the body. Stoppers for decanters should be selected according to style and color and tightly ground to the neck, and for decanters with more valuable cuts (diamond cut, etc.) the stoppers should be polished until completely transparent. The edge of blown and pressed products must be well melted or ground and polished. The inner surface of the bottom of saucers, trays and plates must be flat, ensuring the stability of the glasses placed on them. The edges of the bottom should not be sharp. Stones, scale, crumbling edges, nicks, blown walls, alkaline and surface bubbles, pressing through unfilled (with sharp edges) chips, and under-pressing are not allowed in the vessel.

Household utensils must have the correct shape and specified dimensions. Cracks, stones, large streaks, cloudy bubbles, air leaks and significant thickening are not allowed in this container.

A very important indicator of the quality of glassware is its thermal resistance, i.e. resistance to sudden temperature fluctuations. To check the thermal resistance of the dishes, samples in the amount of 100 pieces were taken from the batch. Thermal resistance was tested by first exposing the dishes to high temperatures (boiling water is poured, immersed in heated water, and other methods), and then low (usually immersed in water with a temperature of 15 or 20°).

Marking. Blown and pressed dishes were marked with a stick-on label, which indicated the brand or name of the plant, product grade, standard number and decoration group. The color of the labels for different types of dishes was different. On packs of glass tableware, the article number of the packaged glassware and the pattern number were additionally indicated.

Packaging and transportation. Crystal products, as well as products made from ordinary glass, but with valuable cuts, were wrapped in paper, and then in shavings and packed into bundles. Pressed tableware and household utensils were packed in straw or shavings. Glassware was transported in covered wagons or containers. Rows of bags or packs were lined with straw. Packs with heavier products were placed at the bottom, and with lighter ones at the top.

Storage. Glass is an easily breakable product; therefore, the warehouse for its storage had to be spacious, dry and convenient for receiving, placing and issuing goods. Glassware was stored on shelves and racks; it was laid on them not flat, but with its end, on the upper shelves it was lighter and slow-moving, on the lower shelves it was heavier, in particular pressed.

Decorating glassware with a diamond cut (fourth difficulty group)

Decorating glassware with a diamond cut (fifth difficulty group)

Decorating glassware with a diamond cut (sixth difficulty group)

Decorating glassware with a diamond cut (seventh difficulty group)

- Look at it! Isn't it amazing? We'll look into it.

- No, we'll throw it away!

Farscape

Many people are concerned about the question of whether it is possible to use dishes after decorating them with dotted or other contour paintings in the microwave.

We decided to conduct a detailed study and record in photographs what will happen to the contours applied to the glass in this case and whether such dishes can be used for heating in a microwave oven.

To begin with, it is worth saying that the determining condition responsible for the instability of contours on glass is not temperature, but hot water vapor. Acrylic paints (and therefore contours) can withstand high temperatures quite easily, but hot water (and especially steam) will help remove even an old acrylic painting from the glass (which is often used to wash off an unsuccessful painting).

For our research, we took two glasses and made inscriptions on them using the usual outline on glass and ceramics and dried them at room temperature for 24 hours. We additionally subjected the inscription on one of the glasses to classic oven fixation (we placed the glass in a cold oven, heated it to 150°C, maintained this temperature for 20 minutes, turned it off and left the glass to cool, leaving the door closed). Both glasses were filled with water at room temperature, then we microwaved them at 750 watts.

Before boiling

Before the water started to boil, both glasses showed good results. The contour without fastening begins to soften somewhat, but all the contours tenaciously cling to the surface.

After the water boils

Contour without fastening: peels off easily from the surface if you pry it with your fingernail.

Contour fixed: It starts to soften, but it holds.

Thus, the glass with the contour without securing it moves out of position.

But we did not stop in our research and continued to mock the dishes.

After four minutes of boiling

The secured contour also begins to peel off. However, if you compare the sensations, it is still more difficult to tear it off the surface than a loose contour.

Important Note: If you do not touch the peeling contour, but simply set the glass aside to cool, then after the glass has cooled, the contour again begins to adhere securely to the surface. It was as if nothing had happened!

Conclusion

Dishes with an outline applied to the surface can be used for heating in a microwave oven, but with restrictions:

Do not neglect fastening;

Do not bring to a boil (that is, you can reheat, but you should not boil);

Do not attempt to scrape off the pattern until the pan has cooled.