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The deformation of flat products is determined by measuring the gap between the edge of the product and a flat plane using a measuring wedge. Deformation of hollow products - by determining the difference between the maximum and minimum diameters; products on the leg - by determining the difference between the maximum and minimum height of the edge of the product, installed on a flat surface.

The strength of surface bubbles is checked by light pressure with a special metal rod 300-400 mm long, having a rounded end with a diameter of 1-1.5 mm.

The adhesion strength of silicate paints and films of precious metals on products is determined by wiping the products with a flannel cloth.

3.2 Requirementstoqualityglasscrockery

IN products made of colorless glass, slight color shades are allowed that do not spoil the presentation. A difference in the intensity of coloring of the same product made of colored and applied glass, caused by uneven wall thickness, and various color shades of decor obtained by heat treatment of zinc sulphide glass, are allowed without spoiling the presentation.

On the areas of products decorated with colored chips, foreign materials that do not spoil the presentation are allowed. inclusions with a size of not more than 1 mm in an amount of not more than 3 pcs. (for small and medium-sized products), not more than about pcs. (for large and extra large).

For defects that cannot be measured, approval of samples agreed with the consumer is allowed.

Local accumulations of midges, cut edges, adhering pieces of glass, burrs, matte coating on the edges, as well as shortening and elongation of the lines of the pattern with a size of more than 4.0 mm are not allowed in the dishes.

The following defects are allowed:

svil, rarely located, not spoiling the presentation;

a bubble in the form of a "sickle", which does not spoil the presentation at the junction of the vessel and the leg, the leg and the bottom, the handle and the vessel, decorative elements:

scree, edge remelting, processed chips and crevices, traces of surface disturbance, traces of molds and scissors that do not spoil the presentation;

traces of distillation and polishing, defects in decorating with preparations of precious metals, luster and silicate paints, underfinishing and elongation of the lines of the pattern when decorating with ring lines, twisting in products of mechanized production that do not spoil the presentation.

In addition, in products with a stem, the asymmetry of the junction of the vessel and the bottom is allowed without spoiling the presentation, and in the places of the fusion of the vessel and the legs, the legs and the bottom, there is also an annular thickening or waviness.

The “mound” on the decorated items must be melted, without cutting glass particles, and must not crumble. The seams and the end surface of the upper edge of the products must be smooth.

Lids and plugs must be matched to products. Lids should freely cover or enter products. Stoppers with an unground stem should freely enter the neck of the product. The lapped stem of the cork should fit snugly against the neck of the product, a barely noticeable swing of the cork in the neck is allowed. In toilet utensils, the stem of the cork should be lapped.

The product must be stable on a flat horizontal surface.

Glasses and saucers for tea, plates for hot food must be thermally stable. Blown products should not collapse at a temperature of 95-70--20°C, pressed 95--60--20°C.

The total number of permissible defects in appearance in one small product is no more than 2, medium - 3, large - 4.

When tapped, crystal products emit a long melodic ringing. The sound effect is enhanced by an increase in the lead oxide content and a decrease in wall thickness: products with a drop-down shape have a greater sound effect.

A feature of crystal products is also a light effect, depending on the amount of lead and the angle of cutting. At a faceting angle of 90 degrees, the reflection of the light incident on the facet is greatest. The reflection coefficient is directly proportional to the content of lead oxides in the glass.

Crystal products are made massive and thick-walled, so they can be applied with deep diamond edges and thereby increase the reflection of light.

depending on the quality of the glass. ways of producing and processing products are divided into 1st and 2nd grades. Products must have a shiny smooth surface, polished to full transparency.

In colorless products, slightly pronounced bluish hues are allowed that do not spoil the presentation.

Products made of glass and crystal, subjected to sudden heating and cooling, mechanical stress during operation, must have the necessary thermal resistance and mechanical strength, especially to impact.

Consumer properties (utility) of glass products used in everyday life and in the field of public catering are determined by a set of properties - functionality, economy, aesthetics, comfort (convenience, hygiene), reliability (strength, durability), etc.

The functional properties of glass products depend on the nature of the glass, shape, size and purpose of the products.

Ergonomic properties of products, first of all, ease of use (comfort) and hygiene of glass products.

The comfort of household utensils is determined by the convenience of performing its functions, keeping it clean, and storing it. At the same time, the shape and capacity of the product, the presence and location of the handles, and the correspondence of their shape to the fingers are taken into account. Assessing the convenience of caring for products, they pay attention to the diameter of the upper hole, the nature of the surface, the presence of roughness, sharp, cutting and scratching areas, corners and recesses, as well as ease of transportation, packaging, storage of products.

The hygienic properties of dishes are primarily due to the nature and properties of glass. Products must have high chemical resistance, must be harmless to the human body. When assessing hygiene, they take into account the simplicity and ease of removing various kinds of contaminants from the surface of products, keeping them clean.

The aesthetic properties of glass products are characterized by the integrity of the composition, the rationality of the form and information content.

Indefinite contours of both the entire product and its elements, unfortunate color and pattern, hiding the natural properties of the material, worsen the aesthetic perception of the shape of the product.

The ratio of the dimensions of the parts, sides, pattern characterizes the proportionality of the product.

The reliability of glass products is determined by their durability. Less reliable are products with attached parts, on a high leg, of complex configuration.

Products must have a shiny smooth surface, polished to full transparency.

The edge and end surface of the upper edge of the products must be melted or polished. Facet is applied to the edge of the upper edge of the products or other types of processing are used. Lids and plugs must be matched to products.

Lids should freely cover or enter products. The difference between the diameter of the cover and the edge of the body (or neck) should not exceed 2 mm.

Stoppers with an unground stem should freely enter the neck of the product. The lapped stem of the cork should fit snugly against the neck of the product. In toilet utensils, the stem of the cork should be lapped.

The spout of the product should be located opposite the handle.

Fixing sticky parts and decorative elements should be simple.

The bottom of the products must be smooth, clearly polished, ensure a stable position on a flat horizontal surface. The inner surface of the bottom of trays and saucers should ensure the stability of the products placed on them.

Products in the set must be selected so that the difference in height between them does not exceed the permissible deviation from the parallelism of the edge of the bottom plane.

The difference in wall edge thickness should not be more than 0.5 mm for products with wall thickness up to 3 mm inclusive and 1 mm for products with wall thickness over 3 mm.

The quality of household glassware depends on the presence of defects that adversely affect its mechanical, thermal, optical, aesthetic and hygienic properties.

Defects in glass products are divided into three groups - defects in glass, production and processing.

The influence of a particular defect on the quality of the product depends on its type, location, size, and also on the size of the products.

According to these features, some defects are allowed with restrictions on the number, size and location, while others are not allowed at all.

3.3 Evaluation of the labeling of glassware from different manufacturers

Products are marked on a paper label, which is glued directly to the product (the use of silicate glue is not allowed) or during the production process. The marking of consumer (group and (or) individual) containers, group packaging made of paper and shipping containers is applied to a paper label or stamp.

It is allowed not to apply marking on consumer packaging packed in transport.

The labeling of products on a paper label indicates the following data:

Trademark and (or) name of the manufacturer;

Vendor code;

Mass fraction of lead oxide (only for lead crystal);

Designation of this standard.

The label is placed on each product. In sets, the label will be placed on at least one product, in services - on the largest product and at least two others. It is allowed not to indicate the article in the labeling of products packed in individual containers.

Marking in the process of development must contain a trademark or the name of the manufacturer.

The composition of the kit or service is indicated on the consumer packaging or on the largest product. It is allowed, in agreement with the consumer, not to apply marking on products or to apply to part of the products in a batch.

Products intended for export are marked in accordance with the terms of the agreement or contract.

In the marking of consumer (group and (or) individual) containers and group paper packaging indicate the following data: trademark and (or) name of the manufacturer; name of products; vendor code; the number of products in a packaging unit (for group packaging); number of controller and packer; designation of this standard.

Transport marking - in accordance with GOST 14192 with the application of the handling sign "Fragile - Caution".

It is allowed to apply the image of a manipulation mark on a label intended for marking containers.

The evaluation of the labeling of the submitted samples for compliance with the labeling requirements of the standard is presented in Table 3.2.

Based on the evaluation results, it can be concluded that sample No. 3 Melanie's dinner plate and sample No. 4 Dripping Black dinner plate do not have a manufacturer's trademark, and for all other indicators, all samples contain all the necessary information.

Table 3.2

Assessment of marking for compliance with the requirements of GOST

3.4 Organolepticgradequalityglasscrockery

Organoleptically in glassware determine:

The presence of defects;

Stability on a flat horizontal surface;

For products characterized by height and diameter, groups are determined (small, medium, large) by the largest size.

The evaluation results are shown in Table 3.3.

According to GOST 30407-96 (ISO 7086-1-82, ISO 7086-2-82) Crockery and decorative glassware. General technical conditions determined the resistance of the decor to the effects of alkaline solutions.

The method is based on determining the resistance of the decor to the effect of 1% - in a vessel with a 1% solution of baking soda at a temperature of (20 ± 5) ° C so that the decorated areas of the products are half covered with the solution. The solution is brought to a temperature of (60±5)°C and incubated for 15 minutes. After soaking in the solution, the product is removed, cooled and wiped dry. The areas of decor that have been exposed to an alkaline solution are compared with areas that were not immersed in it. The surface to be tested shall remain unchanged.

The results of determining the resistance of the decor to the action of alkaline solutions showed that in all samples, the decor treatment areas were not damaged and coincided with the untreated areas.

Additionally, the strength of fixing the decor applied to the surface of the product was checked using mechanical influences - rubbing with a dry cotton cloth for 30 seconds with force. In all samples, the destruction of the decor was not revealed. The decor surface remained unchanged.

Table 3.3

Assessment of the main indicators of the studied samples

3.5 Gradeconsumerpropertiesglasscrockery

According to GOST 4.75-82 “Sized glassware. Nomenclature of indicators" consumer properties and their indicators include the following:

Purpose indicators - the chemical composition and density of glass, the shape and main dimensions of products, their stability on a flat surface;

Reliability indicators - impact strength, hardness, heat resistance, water resistance, fastening strength of parts, annealing quality indicators;

Indicators of ergonomic properties - the content of harmful substances;

Indicators of aesthetic properties - the accuracy of reproduction of the author's sample, indicators of compositional integrity, informational expressiveness, perfection in the production of products, as well as refractive indices, average dispersion, light transmission, cutting angle;

Economic indicators - the mass of products (consumption of raw materials), cost.

The most important consumer properties of glassware are the following organoleptic indicators: aesthetic and ergonomic properties.

For our study, 4 parameters of aesthetic properties are most suitable: decoration, perfection of form, compliance with modern style and perfection of production performance of products.

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

Ease of use is characterized by an indicator of the conformity of the mass of the product with the power capabilities of a person, its design - with the size and shape of a person's hand. Usability indicators are evaluated by an expert method in points. Thus, choosing from ergonomic properties for the range of consumer properties: ease of use and weight of the product.

The assessment of consumer properties was carried out by the organoleptic method using a rating scale according to a 5-point system.

Table 3.4

Grading scale on a 5-point system

After conducting a study of the quality indicators of the selected samples and obtaining the results, Table 3.5 was compiled.

Table 3.5

The results of the study of consumer properties on a 5-point rating scale

pits established in the standards (GOST 15467-79), when assessing consumer properties and product quality indicators, two groups of methods for determining weight coefficients are used:

1) Analytical methods for determining the weight (these methods include the method of regression dependencies, the method of equivalent ratios)

2) Expert methods for determining weight (these quality assessment methods include the preference (or evaluation) method, the ranking method, the pairwise comparison method, the sequential comparison method).

The preference method is used if the number of indicators included in the group indicator of a higher level does not exceed four. When evaluating the most significant qualitative indicator, the expert assigns a weighting coefficient equal to one, and the weighting coefficients of the rest are determined in accordance with their significance compared to the first one.

Ranking - this method is used if it is necessary to reduce the complexity of operations performed by experts, and if the evaluation procedure causes difficulties for experts. Ranking is also used to divide indicators into groups according to their importance. When ranking, it is advisable that the number of indicators does not exceed 10, while rank 1 is assigned to the most significant indicator, rank 2 to the next most important indicator is carried out by mathematical processing.

Paired comparison - this method, based on the requirements of labor intensity, is recommended to be used only when determining the weight coefficients of indicators, the number of which does not exceed 20. At the same time, the most significant one is selected from the pairwise compared qualitative indicators.

Sequential comparison - this evaluation method is the most time-consuming of the above evaluation procedures, but which allows you to get the most reliable and most realistic results. It includes procedures for ranking (or pairwise comparison) and evaluation.

In the presented work, the weight coefficient of the quality indicators of faience dishes will be determined by the method of sequential comparison using the ranking method. In accordance with our own idea of ​​the importance (weight) of quality indicators, in the column "Rank" of single indicators, we put down serial numbers (these will be the ranks of indicators) of indicators. In this case, number 1 will be assigned to the most important indicator, which in this case is the two indicators "appearance" and "form perfection", number 2 - the next in importance, etc.

Table 3.6

Results of a comprehensive assessment of consumer properties

Table 3.7

Comparative characteristics of consumer properties of one type of glassware

Thus, after calculating the weighting coefficients of quality indicators of glass products according to two main group characteristics: an aesthetic indicator and an ergonomic indicator, it was revealed that the aesthetic indicator is the determining indicator in terms of assessing the quality of dining room glassware.

The second most important indicator of quality is the ergonomic indicator of the quality of glassware.

Sample #3 Melanie's Dinner Plate is 4.7, Sample #4 Dripping Black Dinner Plate is 4.6, and Sample #2

CONCLUSION

The development of glass production is one of the constituent factors in the development of the economy of our country. For the manufacture of household utensils and decorative products, oxide glasses are used, in which the main glass formers are oxides of silicon, boron, aluminum, etc.

The production of glass products consists of the processing of raw materials, the composition of the charge, the melting of glass, the molding and annealing of products, their primary and decorative processing.

Consumer properties and the main features of the assortment of glass products are formed at the design and construction stage when creating prototypes and in the process of mass production.

The range of glass goods is quite dynamic and changes due to the constant development of science, the state of production technology, the nature of consumer demand, and the change in style trends.

The range of household products is classified according to the purpose and operating conditions, the composition and color of glass, the method of molding and the nature of heat treatment, types (names), sizes, styles of products, methods and complexity of decoration, completeness. Consumer properties of glass products determine the possibility of their intended use, convenience and reliability in operation, beauty and artistic expressiveness. They depend on the perfection of the author's sample, the properties of glass and the quality of workmanship. Indicators of a number of consumer properties of products are indicators of the physical and chemical properties of glass.

The Enem store, on the basis of a contractual system, works with many suppliers of glassware: CJSC Thermopulse, Bryansk, OJSC Pervomaisky Glass Factory, Pervomaisky, Smolensk Region, Shumyachsky District, LLC Industrial Enterprise INTER-ART XXI, Tver, LLC Firm DP-Trade, Moscow, JSC Glassworks KAVALIER, LLC Uralposuda Gus-Khrustalny.

As a result of a well-established supply chain, the Enem store receives a large assortment of glassware, various series of tableware, glasses, goblets, bowls from leading world manufacturers.

An analysis of the data on the structure of the assortment of glass household utensils sold by the Enem store in 2013 showed that the group of tableware accounted for the largest share in terms of the number and amount of goods sold, since this product is in the greatest demand among buyers. The receipt of glassware in 2013 compared to 2012 increased by 290 items.

glass products must be manufactured in accordance with GOST 30407-96 Crockery and decorative glassware. General specifications and GOST 24315-80 Crockery and decorative glassware. Terms and definitions of types of glass, methods of production and decoration according to the technological regime and standard samples approved in the prescribed manner. Products must be of the correct shape, corresponding to the capacity (dimensions), with a crock of a certain thickness, stable on a flat surface.

To study consumer properties, 3 objects of glass tableware were selected: sample No. 1 Dinner plate LUMINARC Water Color, sample No. 2 Dinner plate Pink roses, sample No. 3 Dinner plate Melanie, sample No. 4 Dinner plate Dripping Black, sample No. 5 Dinner plate DURALEX Beaurivage Pink

A nomenclature of consumer properties of glassware was developed. The most important consumer properties of faience dishes are the following organoleptic indicators: aesthetic and ergonomic properties.

According to the results of the comprehensive assessment of dishes, it was revealed: the highest score - 5 - was scored by sample No. 1 Dinner plate LUMINARC Water Color.

Sample #3 Dinner Plate Melanie - 4.7, Sample #4 Dinner Plate DrippingBlack - 4.6, and Sample #2 Dinner Plate Pink Roses scored - 4.2.

Sample No. 5 Dinner plate DURALEX Beaurivage Pink scored - 3.9 points, which is due to the lack of decoration as the main consumer indicator.

From this it follows that the LUMINARC dinner plate has the best consumer properties among the samples in all respects.

LISTUSEDSOURCES

1. GOST 30407-96 Tableware and decorative glassware. General specifications

2. GOST 24315-80 Tableware and decorative glassware. Terms and definitions of types of glass, methods of production and decoration

3. GOST R 51969-2002 Household utensils from special household glass. General specifications

4. Agbash V.L., Elizarova V.F. Merchandising of non-food products. - M., 2006

5. Vilkova S.A. Commodity research and examination of household goods. - Dashkov & Co., 2012

6. Ilyina M.G. Merchandising of non-food products. Practicum.- M.: Academy, 2010

7. Krasovsky P.A., Kovalev A.A. Product and its expertise. - M., 2008.

8. Lifits I.M. Theory and practice of assessing the competitiveness of goods and services. M., 2007.

9. Nikolaeva M.A. Commodity expertise. - M., 2008.

10. Neverova A.N. Commodity research and organization of trade in non-food products / Ed. - M., 2007

11. Chechetkina N.M., Putilina T.I., Gorbuneva V.V. Commodity expertise. - Rostov n / a., 2006

12. Khodykin A.P., Lyashko A.A., Voloshko N.I., Snitko A.P. Merchandising of non-food products. - Dashkov & K, 2008

13. Yakovenko N.V. Merchandising of non-food products. Workbook.- M.: Academy, 2010.

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The usefulness of glass products for consumers is determined primarily by their compliance with functional, commercial, ergonomic, aesthetic requirements and reliability in operation. Based on the requirements of various categories of consumers for these products, it is possible to single out the corresponding consumer properties. They are based on the natural properties of glass, due to its nature, composition and structure, methods of obtaining products, decoration, as well as compliance with the correct packaging, labeling, transportation, storage and operation.

In view of the greatest diversity of the assortment of glassware among all glass household goods, it is advisable to consider a detailed description of the consumer properties of glass products using the example of glassware. The main function of glassware is the ability to<<принимать>>, save and<<отдавать>> food and drink. The performance of these functions depends both on the design solution of the product and on the type of glass. The type and composition of glass determine the chemical, thermochemical, atmospheric and mechanical resistance of finished products, i.e., the ability<<принимать>> and preserve food and drink. Ability<<отдавать>> food is determined primarily by a constructive solution.

Commercial activities to provide the population served with glass must necessarily provide for a deep knowledge of the consumer properties of products and the requirements of various categories of consumers for individual indicators and in terms of assortment.

FUNCTIONAL properties reflect the possibility of using products for their intended purpose. Glassware must have a sufficiently high chemical resistance (to food, drinks and detergents), the necessary heat resistance (especially kitchenware) and mechanical strength (taking into account the fact that the operation of glassware does not involve significant mechanical stress).

These properties determine the ability of dishes to store food and drinks without affecting their taste, and use it for its intended purpose. Functional properties are also due to the ability<<принимать>> and<<отдавать>>food and drink. Depending on the type of product and its narrow functional purpose, this ability is determined by the shape, size and design features. For example, wine glasses for cognac are made thin-walled, spherical in shape with a narrowed neck. This design allows you to heat the contents with the warmth of the palm and feel the aroma of the drink more fully. In order to minimize the contact surface of the liquid in the decanter with air, decanters are made with a narrow neck. For storing liquid products in considerable quantities and pouring them in large portions, jugs with a wide mouth, a drain and a handle are most suitable.

AESTHETIC the properties of glass are characterized by a number of indicators, among which the main ones are the integrity of the composition, the rationality of the form, the expressiveness of the decor and compliance with fashion. The integrity of the composition is understood as the proportional arrangement and connection of the parts of the product into a single whole in a certain order. The rationality of the form characterizes its compliance with the functional purpose of the product and objects of the environment. The applied decoration methods should increase the aesthetic value of the product and not mask the natural decorativeness of the material used. Compliance of products with aesthetic requirements is determined by an expert method.

ERGONOMIC the properties of glass products determine the ease of use and their hygiene. The ease of use of dishes is determined by the comfort of holding, carrying, washing and using them for their intended purpose. At the same time, it is necessary to take into account the shape and capacity of the product, the presence and location of handles, the correspondence of their shape and size to the user's palms and fingers. In general, the shape, size and color of the product must correspond to the visual and psychophysiological capabilities of the human body. The ease of care of products is determined by the diameter of the upper hole (for hollow products), the presence of hard-to-reach places, corners, protrusions and recesses.

The hygiene of dishes is due to the chemical resistance of glass, the smoothness of the surface, the ability to easily clean them and keep them clean.

RELIABILITY glass products is determined by their durability and storability. Durability is due to physical wear, which depends on mechanical, thermal, chemical and other properties, as well as the wear resistance of the decor. It should be noted that such a property of reliability as maintainability is not typical for glass products.

The considered indicators of consumer properties of glassware are formed at various stages of the production of products. This includes design, preparation of raw materials and glass melting, product molding, annealing, technical processing, decorative processing.

The aesthetic properties of glass household goods are determined by the integrity of the composition, the rationality of the form and information content.

The integrity of the composition characterizes the arrangement, addition and connection of parts into a single whole in a certain order. It is due to the spatial and decorative structure, tectonics, proportions of the shape of glass products.

The rationality of the form characterizes the correspondence of the shape of the product to the functional purpose and environmental conditions, the compliance of the tonal and color solutions of individual elements with the requirements of ergonomics, the style solution - the interior, the manufacturing technology - the properties of the material.

Informativeness of glassware is determined by the symbolism, originality and compliance with their style and fashion prevailing at the time.

The property of reliability of glass products is determined by their durability and storability. The most important is durability, which is characterized by physical and moral wear and tear.

Indicators of a number of consumer properties of products are indicators of the physical and chemical properties of glass.

The most important of them are the following.

The density of glass varies from 2.2 g/cm3 for quartz glass to 3.0 g/cm3 or more for high-lead crystal. It depends mainly on the presence of heavy metal oxides (lead, barium, zinc) in the composition of the glass and affects the mass of products, optical and thermal properties. With an increase in density, the refractive index of light, the brilliance and the play of light in the faces increase, but the heat resistance, strength and hardness decrease.

The mechanical properties of glass are characterized by the absence of plastic deformations, high compressive strength (500-800 MPa) and low tensile, bending (25-100 MPa) and especially impact (15-20 MPa). The strength depends on the chemical composition: it increases with the presence of SiO2, Al2O3, B2O3, MgO in the glass composition and decreases with the presence of alkali oxides, PbO. However, the internal structure of the glass, the state of the surface, and the presence of defects on it have a decisive influence. Strength is increased by hardening, ion exchange in molten salts, deposition of oxide-metal coatings on the surface, and other methods.

The thermal properties of glass are characterized by very low thermal conductivity, significant heat capacity and thermal expansion. The thermal stability of products increases with an increase in the mechanical strength of glass, thermal conductivity and with a decrease in thermal expansion and heat capacity. A measure of heat resistance is the temperature difference that a product can withstand without destruction. Heat resistance of quartz glass - 1000°С, ware from high-quality glass - 95°, ware from glass-ceramics - 300-600°С.

All methods that increase mechanical strength simultaneously improve heat resistance.

The optical properties of glass are varied. Glasses can be transparent (transmittance of 0.85 or more) and muted to varying degrees, colorless and colored, with a shiny and matte surface. Optical characteristics of glasses - refractive indices and average dispersion, reflection and transmission coefficients; color indicators largely determine the aesthetic merits of dishes. Especially important is the ability of glass to perceive colors that increase the emotional expressiveness of products.

The chemical resistance of glass determines the purpose and reliability of products. It is very high, especially in relation to water, organic and mineral acids (except hydrofluoric). Alkalis and alkali carbonates act more aggressively. Hydrofluoric acid dissolves glass and is therefore used for applying patterns to glass, matting and chemical polishing of products.

According to water resistance, glass is divided into five hydrolytic classes: the first class is glass that is not changed by water, the fifth is unsatisfactory.

According to GOST 4.75-82 “Sized glassware. Nomenclature of indicators" consumer properties and their indicators include the following:

§ indicators of purpose - the chemical composition and density of glass, the shape and main dimensions of products, their stability on a flat surface;

§ reliability indicators - impact strength, hardness, heat resistance, water resistance, fastening strength of parts, annealing quality indicators;

§ indicators of ergonomic properties - the content of harmful substances;

§ indicators of aesthetic properties - accuracy of reproduction of the author's sample, indicators of compositional integrity, information expressiveness, perfection of industrial production of products, as well as refractive indices, average dispersion, light transmission, cutting angle;

§ economic indicators - the mass of products (consumption of raw materials), cost.

Nomenclature of consumer properties of glass household goods

The usefulness of glass products for consumers is determined, first of all, by their compliance with functional, commercial, ergonomic, aesthetic requirements and reliability in operation. Based on the requirements of various categories of consumers for these products, it is possible to single out the corresponding consumer properties. They are based on the natural properties of glass, due to its nature, composition and structure, methods of obtaining products, decoration, as well as compliance with the correct packaging, labeling, transportation, storage and operation.

In view of the greatest diversity of the assortment of glassware among all glass household goods, it is advisable to consider a detailed description of the consumer properties of glass products using the example of glassware. It is easy to see that the main functions of glassware are the ability to "receive", store and "give away" food and drinks. The performance of these functions depends both on the design solution of the product and on the type of glass. On fig. 10.1 shows a group characteristic functional properties glassware.

Type and composition of glass determine the chemical, thermal, atmospheric and mechanical resistance of finished products, i.e. their ability to "accept" and store food and drinks. The ability to “give away” food is determined, first of all, by a constructive decision.

Commercial activities to provide the population served with glassware must necessarily provide for a deep knowledge of the consumer properties of products and the requirements of various categories of consumers for individual indicators and in terms of assortment.

Group indicators ergonomic properties provide for maximum ease of use of products and their hygiene (Fig. 10.2).

Ease of use glassware determines the degree of comfort, i.e., ease of holding, carrying, washing, storing, and this is ensured by the general parameters of the product, shape, size and location of individual parts, weight. hygiene glassware depends on the chemical properties of glass and design features. It is known that glassware is chemically resistant and harmless, however, some paints and compositions used for decoration may not fully meet these requirements due to the content of heavy metal salts in them. The bulky, inconvenient shape and design of products can also reduce their hygiene, making it difficult to clean (wash) in hard-to-reach places.

Glassware, like other products, is designed to perform an important aesthetic function, i.e., to satisfy the spiritual needs of consumers, to educate them in taste, a sense of beauty, to contribute to the creation of coziness in housing, a sense of comfort at the table. Aesthetic properties are formed at the design stage of products, they are largely determined by the unique properties of glass as a material, and depend on the quality of production execution of operations for the formation and finishing of products.

The integrity of the composition provides for the connection into a single harmonious whole of all the constituent elements of dishes: the properties of glass, the shape and design of the product, the proportions and ratio of individual parts, decorativeness (Fig. 10.3).

Rationality of form provides for its consistency, conformity of the form to the purpose of the product and the properties of the material, processing technology.

Information expressiveness(informativeness) of dishes is characterized by the degree of reflection in the form of a product of various social and aesthetic ideas and ideas, for example, national, age, regional traditions (significance).

Product originality determines its difference (dissimilarity) from other similar products.

Reliability is a complex complex property characterized by durability and persistence glassware. Such durability indicators as non-failure operation and maintainability are not typical for glass products (Fig. 10.4). The durability of dishes is determined, in turn, by its physical and moral wear resistance. Optimal is the coincidence in time of performance of utilitarian and aesthetic functions, i.e. physical and obsolescence.

The considered groups and individual indicators of consumer properties of glassware are formed at various stages of the production of products. This includes design, preparation of raw materials and glass melting, product molding, annealing, technical processing, decorative processing.