For example,;I have found that-if titanium acid cake is first added to the zinc sulphate solution, and then the lithopone-produced in the usual manner, that theresultaht product, upon mufiing, will form bluish compounds of titanium, which discolor somewhat the final product, and this discoloration is disadvantageous.
In addition to pigments and sunscreens, titanium dioxide is also used in the production of paper, food products, and pharmaceuticals. In the paper industry, titanium dioxide is added to paper coatings to improve brightness, smoothness, and printability. In the food industry, titanium dioxide is used as a whitening agent in products such as candies, chewing gum, and icing. In the pharmaceutical industry, titanium dioxide is used as a coloring agent in tablets and capsules.
As early as sixty years ago, zinc sulphide was first thought of as a pigment for coloring India rubber and a patent for the process of its manufacture was issued in England. But it was not until twenty years later that zinc sulphide and its manufacture was seriously considered as a pigment for paint, and in 1874 a patent was issued for a process of manufacturing a white pigment, composed of zinc sulphide and barium sulphate, known as Charlton white, also as Orr's white enamel. This was followed in 1876 by a patent issued to a manufacturer named Griffith and the product, which was similar in character to Charlton white, was known as Griffith's patent zinc white. In 1879 another patent for a more novel process was obtained by Griffith & Cawley, the product made under this process proving the best of the series placed upon the market up to that date. After that time many new processes were patented, all, however, tending to the same object, that of producing a white pigment, composed of zinc sulphide and barium carbonate, the results, however, in many cases ending with failure.