The Influence of Soap on Starch-Pigment Coated Paper

A literature survey is presented concerning the effects of soap on the rheological properties of coatings, and upon the physical properties of the coated paper. The influence of sodium, ammonium, and calcium stearates is investigated, and it is found that soaps produce desirable effects upon both the flow properties of coating colors and the physical properties of the coated paper. The experimental results indicate that sodium stearate is superior to either ammonium or calcium stearate, in that all of the properties tested for are either enhanced or remain about the same when sodium soap is added to the coating, whereas the ammonium and calcium soaps produce both desirable and deleterious effects