Fig. 13.—Portable Gas Heated Japanning and Enamelling Stove fitted with Shelves, Thermometer, etc.
Pigments Suitable for Japanning with Natural Lacquer.
White Pigments.—Barium sulphate and bismuth oxychloride. These two are used for the white lacquer or as a body for coloured lacquers. When the lacquer is to be dried at a high temperature barium sulphate is preferable, but when it is dried at an ordinary temperature bismuth oxychloride is better. Since the lacquer is originally of a brown colour the white lacquer is not pure white, but rather greyish or yellowish. Many white pigments, such as zinc oxide, zinc sulphide, calcium carbonate, barium carbonate, calcium sulphate, lead white, etc., turn brown to black, and no white lacquer can be obtained with them.
Red Pigments.—Vermilion and red oxide of iron. These two are used for the red lacquer, but vermilion should be stoved at a low temperature.
Blue Pigment.—Prussian blue.
Yellow Pigments.—Cadmium sulphide, lead chromate and orpiment.
Green Pigment.—Chromium oxide (? Guignet's green).
Black Pigment.—Lamp black. This is one of the pigments for black lacquer, but does not give a brilliant colour, therefore it is better to prepare the black lacquer by adding iron powder or some compound of iron to the lacquer.
Various mixed colours are obtained by mixing some of the above-mentioned pigments.