Патент USA US2111576код для вставки
1 2,111,575 Patented Mar. 22, 1938 PATENT orrics UNITED ‘ STATES 2,111,516 FROSTED GLASS AND METHOD OF MAKING SAME Olus J. Stewart, Lexington, Ky‘ No Drawing.’ Application May 24, 1935. Serial No. 23,336 3 ‘ (o1. 91-16) 11- Claims. treated surface of the glass is characterized by The present invention-relates to improvements minute surface fractures running to a large ex in frosted glass and the method of making the tent in parallel lines, and analysis shows that sodium ‘atoms of the, glass have been displaced by lithium atoms. The presence of the minute 5 surface fractures is undoubtedly due to the fact same, and aims generally to provide a new and different character of frosted glass as well as to provide a new, simple and economical method for the production of such glass. Generally my invention provides a new frosted glass in which certain of the sodium atoms, as that the lithium atoms are smaller than the dis- - placed sodium atoms which causes a surface shrinking of the‘ glass, and the formation of the vfor example, in a soda lime glass, .are displaced minute fractures. The portions of ,the frosted 10 10 by a metal having a smaller atom, such as lith glass surface between the minute surface frac ium, at least on the surface of the glass, which Atures are characterized as ?at top, sloping sided produces a new and different product in the form prismatic blocks. This, I believe, is responsible of a smooth, satiny attractive pearl white frosted for the high degree of refraction and dispersion light which is a characteristic of my new 15 Advantageously the process is carried out by - -of glass, because when strongly illuminated by a bringing the glass in contact with molten lithsurface. '15 > ~ light located a few inches from the glass, the source of illumination does not appear localized but the entire surface of the glass is uniformly ium compounds, as by, immersion, coating or spraying, and maintaining the contact between the glass and'the molten lithium, compounds suf ficiently long to produce a frosted surface of the 2 lighted and serves as a secondary source of light. 20 Although the surface of the glass produced in accordance with my process is characterized by minute surface or skin fractures, the strength desired intensity on the glass. More speci?cally the process comprises the steps of producing a bath of molten lithium com of the glass of ordinary thickness is not impaired and experimentally the treated glass will with- 25 pound, one of the most suitable being anhydrous 25 lithium nitrate, either alone or combined with stand as much pounding and rough handling as other lithium compounds. The temperature of , untreated glass. the molten lithium compound bath may be varied somewhat as desired, but I have found that a molten lithium bath at a temperature of 300° C. 30 gives satisfactory results. . Advantages of my invention are man . The new method of producing frosted glass is relative ly economical in practice and may be applied to 30 ' semi-plastic glass either as it comes from a form The piece or article of glass desired to be frost ed is then heated to a temperature approximat ing machine or merely by heating previously annealed glass to a temperature approximately _ ing the temperature of the lithium bath, or to such temperature thatundue strain will not be 35 set up in the glass and crack it when the glass and lithium bath are brought into contact. The equal to- the temperature of the lithium bath 35 and then dipping the glass in the bath. 'Thus the invention is highly useful in the pro . heated glass is then brought in contact with the duction of decorated glassware, and for the pro molten lithium bath, as by immersion, spraying’ or duction of arti?cial pearl buttons and the like. otherwise, and this contact is maintained for a More particularly, however, the invention is .period of time su?lcient to- produce the intensity especially useful as a frosted glass for illuminat- 4° 40 ing purposes, as for example, in the production of the frosting desired which may be varied ac cording to the concentration of the lithium bath, of incandescent light bulbs which may be frosted the temperature of the bath or the duration of both inside or outside. Such- bulbs when frosted the treatment, such treatment may be for two according to my invention produce a brilliant 45 45 to fifteen minutes, depending upon the intensity light yet one which is softer, more diffuse and easier on the eyes than - present mommercial of the frosting desired. After the glass is main tained in contact with the lithium bath. for a frosted lamp bulbs. Also the process may be su?lcient time to produce frosting of desired in used to. frost colored glass as well as colorless tensity, the treated glass may be cooled, washed - with tap water, and dried. The glass produced by the above described process‘, is clearly characterized by its smooth satiny pearl white surface. ‘ ' ' ~ Microscopic examination of: the glass- produced according to the above process discloses that the glass. - ' Although I have described several uses- to 50 _ 1 which my invention is particularly adapted, I. do, not intend that the invention be restricted to such uses, as obviously many other uses are ap parent to those skilled in, the art. 55 2,111,678 What I claim as new and desire to secure by Letters Patent is: > - 1. As a new article of manufacture, a frosted prises spraying a surface of the glass with a molten lithium salt. 7. The method of frosting glass which com prises immersing the glass to be treated in a bath glass, 9. surface of which is characterized by at least certain of the sodium atoms being displaced by lithium atoms, said lithium being con?ned to ' ' of molten lithium compound. the surface region. 8. The method of frosting glass which com prises immersing the glass to be treated in a 2. A glass body characterized by having a mi bath of- molten lithium compound and main nutely fractured surface imparting a frosted ap 10 pearance, said surface containing lithium atoms taining the time of immersion sufficiently long substituted for sodium atoms in the surface re- - to produce a frosting of the desired intensity. 9. The method of frosting glass which com 10 gion of said body. ' ~ prises immersing the glass to be treated in a 3. A glass electric light bulb having a minute 'ly fractured surface contalning lithium atoms bath of molten lithium compound, and variably controlling the temperature of the bath accord 15 substituted for sodium atoms, the lithium atoms ing to the intensity of the frosting desired. and fractures being con?ned to the surface and 10. A method of frosting a glass surface com 15 causing a frosted effect. _ prising subjecting the surface in a heated con 4.. The method of frosting glass which com dition to the action of molten lithium nitrate to produce a fracturing of the glass essentially 20 ‘ prises subjecting a surface of the glass to a molten lithium nitrate. con?ned to the surface. 5. The method of frosting sola-lime glass which 11. A method of frosting a glass surface com 20 comprises spraying a surface of the soda-lime prising subjecting the surface to the action of a glass with a molten lithium compound. molten'lithium compound to produce a fracturing 25 of the glass essentially con?ned to the surface. 6. The method of frosting glass which com OLUS J. STEWART.