VITREOUS ENAMELING 25 



Immersed in cone, sulfuric acid at 90-150 degrees, then washed with water 

 at 65 and then at 100 degrees. 



1,104,266. M. Mayer and B. Havas. White opaque enamel. July 21, 

 1914. C. A., 8, 3106. (204, 896). 



Contains spinel and preferably small amounts of zirconium, titanium 

 stannic or silicon oxide as opaquing material. 



1,104,679. I. Kreidl. Opaque enamel. July 21, 1914. C. A., 8, 3106. 

 (204, 940). 



Contains colloidal zirconium oxide. 



Reissue 13,791. I. Kreidl. Making an opaque material for white enamels. 

 Aug. 25, 1914. C. A., 8, 3494. (205, 1291). 



Natural zirconium silicate is heated with 4 times its weight of sodium 

 hydroxide to 500-600 degrees, washed, dried, and heated to a glowing tem- 

 perature. 



1,117,197. I. Kreidl. White enamel. Nov. 17, 1914. C. A., 9, 136. 

 (208, 682). 



The opaquing material is formed of zirconium oxide combined with silica 

 and about 3-4 per cent of alkali metal. 



1,118,898. P. Eyer. Enamel glazing. Nov. 24, 1914. C. A., 9, 136 

 (208, 1314). 



1,119,905. C. A. W. Vollrath. Enamel for coating machine. Dec. 8, 

 1914. C. A., 9, 239. (209, 381). 



Finely comminuted colored glass in addition to the ordinary enamel to 

 form a speckled coating. 



1,123,760. I. Kreidl. Making a material for opaquing white enamel. 

 Jan. 5, 1915. C. A., 9, 701. (210, 193). 



1,124,380. O. Zahn. Muffle furnace for enameling. Jan. 12, 1915. 

 C. A., 9, 701. (210, 454). 



1,126,621. A. de Back. Recovering iron and steel from waste enameled 

 articles. Jan. 26, 1915. C. A., 9, 592. (210, 1327). 



1,128,691. I. Kreidl. Opaquing materials for enamels, glass, etc. Feb. 

 16, 1915. C. A., 9, 1103. (211, 797). 



Hydrates zinc oxide containing 2-7 per cent combined alkali and a few 

 per cent of water, varying inversely as the amount of alkali. 



1,129,300. I. Kreidl. White enamel. Feb. 23, 1915. C. A., 9, 1103. 

 (211, 1047). 



The opaquing agent consists of zirconium oxide combined with a smaH 

 amount of alkali. 



1,140,105. Charles Bickmeier and Daniel A. Listen. Continuous-burning 

 furnace for burning enamel ware. May 18, 1915. /. Soc. Chem. Ind. 34, 

 717. (214, 914). 



1,150,467. J. Weber. .Opaquing composition for use in vitreous enamels. 

 Aug. 17, 1915. C. A., 9, 2701. (217, 871). 



Hydrates stannic oxide containing about 10 per cent water and 3-5 per 

 cent of alkali. 



