46 CASEIN. 



Sundry Recipes for Casein Paint. 



Casein 144 parts by weight. 



Slaked lime ..... 7 



Spanish white 280 



Earth pigment 2 



Water 160 



Another proved recipe is : 



Skim milk J gall. 



Freshly slaked lime 6 oz. 



Linseed oil or poppy oil 4 oz. 



Spanish white 3| Ib. 



The analysis of a casein paint for coarse work gave the 

 following percentage composition: Dry residue, 51 '6 per 

 cent. ; water, 48 '4 per cent. ; ash in residue, 297 per cent. ; 

 nitrogen, 0'537 per cent. ; (casein, 3'36 per cent.). The ash con- 

 sisted of 24*6 parts of calcium oxide, 31 parts of silica, and 

 2*0 parts of ferric oxide. The silica was derived from the 

 earthy pigment used. This paint can be imitated by slaking 

 30 parts of quick-lime with 70 parts of water, allowing the 

 product to cool down and then stirring into it 20 parts of 

 white curd obtained from separated milk. A suitable amount 

 of pigment is added to the mixture. 



CASEIN ENAMEL PAINT. 



To prepare casein enamel paint, soda casein is intimately 

 mixed with enamel colours namely, glass fluxes coloured 

 with metallic oxides (like the preparations used in porcelain 

 painting), the whole being ground in water. The product 

 does not dry with the dull surface of the ordinary casein 

 paints, but has a gloss more nearly resembling that of oil 



paint. 



CASEIN FACADE PAINT. 



This is a new type of ready-made casein paint, the chief 

 peculiarity of which is that it must be protected from contact 



