CS220141B1 - Universal chalk opal glass - Google Patents

Abstract

Universal chalk opal glass is a medium alkaline silica glass, hardened by combined fluoride-phosphorus hardening. The essence of the invention lies in the fact that the glass contains silicon dioxide in a mass concentration of 45 to 76%, aluminum oxide in a mass concentration of 0.2 to 12%, zinc oxide in a mass concentration of 0.05 to 20%, calcium oxide in a mass concentration of 0.05 to 10%, sodium and/or potassium oxide in a mass concentration of 13 to 18%, phosphorus pentoxide in a mass concentration of 0.10 to 10% and fluorides in a mass concentration of 0.05 to 6%. It may also contain components affecting the fusibility of the glass and the stability of the glass state, as well as dyes. The glass according to the invention is universally applicable in glass production, especially in the jewelry industry.

Description

The present invention relates to chalk opal glass based on fluoro-pyrophosphate, quenching with an increased rate of temperature-stable turbidity, which is universally applicable in the glass industry, particularly in the glass industry.

Essentially, two types of Cretaceous Opals cloudy with combinations of fluoride and phosphorus pentoxide are known from the literature, namely hard glasses for mosaic making and for building cladding or other special technical purposes and soft glasses for processing into a variety of utility, jewelery and art products.

The first group consists of chalk opals with a low content of alkaline oxides, which does not exceed 12.5% by weight. The required stability of the haze and glass state of the glass is achieved by adding 7 to 15% by weight of boron oxide in combination with alumina and / or lead oxide. However, these glasses with a higher phosphorus pentoxide content show a certain tendency to devitrification and can only be safely processed in a relatively narrow temperature range. Therefore, chalk opals of this type are generally not suitable for continuous production.

The second group consists of glasses with a high content of 18.5 to 22% by weight of alkali oxides, the base opaque being calcium phosphate in the presence of 1 to 2% by weight of theoretically introduced fluorine. Cretaceous opals of this type, colored by oxides of copper, chromium, manganese, cobalt, nickel and iron, have been produced on a wider scale in the jewelery area, as so-called saturated colored glass, which is not flush. Quenching agents silicon dioxide alumina zinc oxide calcium oxide sodium and / or potassium phosphorus pentoxide fluorides

The glass may further comprise:

barium oxide barium oxide strontium oxide beryllium oxide magnesium oxide lead oxide lithium titanium dioxide zirconium tin dioxide arsenic oxide antimony trioxide lanthanum sulphate sulphide sulphide oxide oxides other glass oxides and Kryllite. The glass is melted in multi-pan ovens and processed by hand into bars and lamipes. sticks, which are the raw material for the production of jewelery. Saturation occurs slowly during multiple cooling and heating of the glass in the temperature range of its processing, and therefore are not mercury. glasses suitable for the machine production of bars, or for the direct shaping of moldings from a melting aggregate. The handmade production of rods and rods [semi-finished products places great demands on the skill and practical experience of glassmakers and is very laborious. Due to the critical shortage of skilled workers, the technology used does not meet the considerable demands on the quantity of bar, ie their quality and wide range of colors. The white chalk opal and the rich color hand-derived glass derived therefrom are characterized by high thermal expansion and, consequently, lower heat resistance and a very low chemical resistance to water which does not comply with the fifth grade of the standard GSN 70 05131. In addition, this group of turbid glasses ranks among the worst abrasive glasses ever. It takes four to five times longer time to grind them than in the case of clear fashion jewelery glasses.

Universal chalky opal glass solves most of the deficiencies of both types of aging eskel. The essence of the invention is that the universal chalk opal glass contains the following basic components in the stated weight concentration:

.45 to 76% 0.20 to .12% .0.05 to 120 P / o .0.05 to 10 P / o. To 18 P / o Q / 10 to 10 P / o -0.05 up to 6%

tracks up .6 After ..stopy .až 20 May ° / o boty.až • 4 ° / o stop .až .4 -% boty.až 5 % boty.až 35 % tracks up .4 % boty.až .10 % tracks up 3 ° / o tracks up 2 % tracks up 5 % tracks up 3 % tracks up 6 % tracks up 2 % tracks up 1 % tracks up 2 ® / o tracks up 12 % tracks up 5 %

chromium trioxide tracks up 2% manganese oxide tracks up 7% copper oxide tracks up 4% cobalt oxide tracks up 2% nickel oxide tracks up 2% vanadium tracks up 5% uranium tracks up 4% cadmium tracks up 0 ° / o selenium tracks up 1% telur tracks up 1% silver tracks up 1%

The versatile chalk opal glass according to the invention, in comparison with some turbid glasses for technical purposes, consists in a higher thermal stability of the turbidity, in a better melting ability and lower production costs. In contrast to soft chalk opals for handmade glass, the glass according to the invention is characterized by a high turbidity rate, a higher saturation and whiteness of the haze, a lower thermal expansion, a higher heat resistance and a significantly better abrasion. In addition, it excels in its good chemical resistance to water, which ranges from the second to fifth class according to ČSN 70 05 31.

Universal chalk opal glass is medium alkaline silica glass, hardened by combined fluoride-phosphor hardening. The required haze and glass state stability is achieved according to the invention by the interaction of alumina, zinc and calcium oxide, the rate of haze formation being controlled for varying purposes by varying fluoride concentrations.

The universal coated opal glass according to the invention is suitable for melting on various types of melting aggregates, heated by gas, fuel oil, electrically or in combination, in ladle furnaces, daily or continuous baths.

The melted glass can be processed by machine or hand into rods and sticks from which jewelery moldings of various shapes and sizes are obtained by hand pressing. In addition, the bar can be remelted in crucible or tray type ovens and molded on mechanical squeezers.

The chalk opal glass according to the invention can also advantageously be processed directly from a ladle or bath melting furnace manually or mechanically into various kinds of turbid products.

Universal chalk opal glass also brings a number of economic benefits. In addition to the savings of qualified glassmakers, considerable cost savings are achieved in the transition to mechanical processing of glass. In addition, the invention makes it possible to make full use of domestic sources of glass raw materials and to save some expensive raw materials such as dicalcium phosphate, borax or cryolite.

Versatile chalk opal glass is suitable for wide use in the glass industry for a variety of white goods and for application to a wide variety of saturated colored glasses. The following examples of the chemical composition of glass illustrate the extensive application possibilities of the invention, particularly in the jewelery industry.

Example 1

Universal chalk opal glass of white color with increased rate of formation of stable turbidity and good physical and chemical properties, for example, has the following chemical composition, expressed in mass concentration:

silicon dioxide 63% aluminum oxide 3% zinc oxide 7% calcium oxide 5,5 ° / o sodium oxide 11,5% potassium oxide 3% phosphorus pentoxide 5% fluorides 2%

Said glass consists of all the principal components of the glass according to the invention and has the following physical and chemical properties: mean coefficient of linear thermal expansion α = (9.3 ± 0.4). . 10 ^-6 "C ¹ transformation temperature T _g = 475 ± ± 10 ° C, total reflection of the white light was 89%, and chemical resistance to water corresponds to the third class according to CSN 70 05 31st temperature profile of the glass viscosity curve satisfies the quality glass for jewelery and utility purposes.

The main advantages of the glass according to Example 1 over chalk opals for manual production are lower thermal expansion, higher heat resistance, substantially better chemical resistance to water and dilute acids, increased haze formation rate, markedly higher haze and whiteness and improved abrasion. Said glass exhibits about 10% higher total reflection of white light than chalk opals for handmade, and is therefore also very suitable for receiving or underneath clear glasses.

The glass according to Example 1 can be successfully used in all areas of glass production, in particular for machining up to

20141 bars and for the direct production of a variety of costume jewelry, utility and technical goods.

Example. 2

The universal chalk opal glass of white color with increased rate of formation of stable turbidity and "great physical and chemical properties" has, for example, the following chemical composition, expressed in mass concentration:

silicon dioxide 63 % alumina 3 % zinc oxide 4.8% calcium oxide 2 % natron 11.5% potassium oxide 3 % Phosphorus pentoxide 5 % fluorides 2 % boric oxide 1 % barium oxide 4 % magnesium oxide 0.5% zirconium oxide 0.2%

Said glass constitutes all of the principal components of the glass of the invention and some other non-staining components which favorably affect the fusibility of the glass and the stability of the glass state and turbidity in the glass processing temperature range.

The glass according to Example 2 is characterized by the same mechanical and optical properties and the same chemical resistance to water as the glass in Example 1 and fulfills all other requirements for high quality chalk opal for machine or manual processing into bar blanks or for direct production of various white goods for various purposes .

Example 3

Universal chalk opal glass of green turquoise color with increased thermal stability of turbidity and improved mechanical properties, for example, has the following chemical composition, expressed in mass concentration:

silicon dioxide 66 ^l % alumina 3 ' ^s % zinc oxide 2.5'% calcium oxide 2 ^; % sodium oxide 12 Ψο potassium oxide '3 Ψο phosphorus pentoxide 4% fluorides 1.6% barium oxide 4% magnesium oxide 0.5% titanium dioxide 0.5% sulphates 0.1% chromium oxide' 0.2% copper oxide 0 , 6%

Said glass constitutes all of the principal glass components of the invention, some other non-coloring components and chromium and copper oxides as colorants.

The advantages of this green turquoise glass are, in particular, the reduced initial crystallization temperature of the glass, the high thermal stability of the turbidity even at lower working temperatures, and the higher heat resistance and substantially better abrasive properties than the chalk opals for handmade.

In addition, the glass according to Example 3 is characterized by an increased turbidity rate, almost the same temperature profile of the viscosity curve and the same chemical resistance to water and dilute acids as the glasses in Examples 1 and 2, and therefore also universally applicable for machine and manual processing for bar and for the direct production of a wide range of jewelery, technical and utility goods.

Claims (3)

Subject matter of the invention 1. Universal chalk opal glass, characterized in that it contains the following basic components in the amount indicated in mass concentration: silicon dioxide 45 until 76 % aluminum oxide 0.20 until 12 '% zinc oxide 0.05 until '20 % calcium oxide 0;05 until 10 % sodium and potassium oxide 13 until 10 % either individually or in combination, phosphorus pentoxide 0.10 to 10% fluorides 0.05 to 6% 2. Universal chalk opal glass according to point 1, characterized in that it contains the following additional components in the amount specified in the mass concentration: boric oxide barium oxide strontium oxide beryllium oxide magnesium oxide lead oxide lithium oxide titanium dioxide zirconium oxide tin dioxide arsenic oxide antimony oxide lanthanum oxide sulfates sulfides chlorides traces up to 6% traces up to 20% traces up to 4% traces up to 4% traces up to 5% traces up to 35% traces up to 4% traces up to 10% traces up to 3% traces up to 2% traces up to 5% traces up to 3% traces up to 6% traces up to 2% traces up to 1% traces up to 2% 3. Universal chalk opal glass according to points 1 and 2, characterized in that it contains the following coloring components in the amount specified in weight concentration to achieve various colors: rare earth oxygenates tracks up to 12 % either individually or in mutual combinations, ferric oxide tracks up to 5 % chromium oxide tracks up to 2 % manganese dioxide tracks up to 7 % copper oxide tracks up to 4 % cobalt dioxide tracks up to 2 % nickel oxide tracks up to 2 % from above tracks up to 5 % uranium tracks up to 4 % cadmium tracks up to 2 % selenium tracks up to 1 % tellurium tracks up to 1 % silver tracks up to 1 %