12 VITREOUS ENAMELING 



Landrum, R. D. The necessity of cobalt oxide in ground coat enamels for 



sheet steel. Trans. Amer. Ceram. Soc., 14, 756-67; C. A., 7, 232. 

 Rickmann, R. Testing of enamels containing antimpny. Z. angew. Chem., 



25, 1518-19 (1912); /. Soc. Chem. Ind., 31, 775. The sample is boiled 



for half an hour with 4 per cent acetic acid or 2 per cent tartaric acid. 



The antimony in solution is titrated with permanganate. The meta- 



antimonates are not attacked by this treatment. 

 Rickmann, R. Coloring agents for white glasses, glazes and enamels. English 



Patent 27,954, Dec. 4, 1912. 

 Rickmann, R. The use of antimony compounds for the production of white 



enamel. Sprechsaal, 45, 115-7 (1912); La Ceramique, 15, 134; C. A., 6, 



1348, 2679; /. Soc. Chem. Ind., 31, 231. Antimony oxide should be 



avoided, but the antimonates are not injurious to health. 

 Rickmann, R. White covering for enamels. French Patent 451,238, Dec. 2, 



1912. English Patent 27,954, Dec. 4, 1912. C. A., 7, 3210; /. Soc. 



Chem. Ind., 32, 604. Antimony is heated to redness with saltpeter and 



an alkaline hydroxide. 

 Schuler, A. J. Process for dulling enamels. English Patent 28,679, Dec. 12, 



1912. /. Soc. Chem. Ind., 33, 81. 

 Shaw, J. B., and Shaw, Lucian. Determining the cost of enameled sheet 



steel cooking utensils. Trans. Amer. Ceram. Soc., 14, 510-5 (1912); 



C.A., 7,230. 

 Staley, Homer F. The cause and control of crazing in enamels on cast iron. 



Trans. Amer. Ceram. Soc., 14, 516-45; C. A., 7, 230; /. Soc. Chem. Ind., 



31, 1129. 

 White enamel with zirconium silicate base. La Ceramique, 14, 204; C. A., 



6, 1665. The natural silicate of zirconium, extracted with hydrochloric 



acid, and then with 4 parts of sodium hydroxide at 500-600 gives a product 



that is bulky and superior to tin oxide. 

 Zahn, O. Burning furnace for enameling. German Patent 263,518, Sept. 



27, 1912. C.A., 8,227. 



1913 



Advantages of the portable muffle furnace in glass, porcelain and enamel 

 works. Diamant, 35, 485-6; C. A., 7, 3003. 



de Back, A. Removing enamels from waste enamel ware. English Patent 

 77, Jan. 1, 1913. C. A., 8, 2235. 



Beige, A. Leadless enamels and faience with reduced content of tin oxide. 

 Sprechsaal, 46, 17-9(1913); J. Soc. Chem. Ind., 32, 142. Instead of dis- 

 pensing with tin oxide, it is reduced to a minimum by fritting with sodium 

 phosphate. 



Bertrand, M. S. V. Enamels of sodium borosilicate. La Ceramique, 16, 

 113-4; C. A., 7, 2841. 



Chem. Fabrik Giistrow, Hillringhaus, and Heilmann. Opaquing agent for 

 white enamels. English Patent 11,749, May 20, 1913. C. A., 8, 3622. 

 This consists of titanic acid and zirconium oxide. 



