Process for the preparation of polyvinyl alcohols which are soluble in cold water and have been absorbed onto pigments

摘要

A process is provided for the preparation of polyvinyl alcohols absorbed onto pigments. In the process 10% to 30% strength by weight of aqueous solutions of partially hydrolyzed polyvinyl alcohols or fully or partially hydrolyzed vinyl alcohol copolymers, which are soluble in cold water, are spray-dried after the addition of 20% to 40% by weight, relative to the total solids content of the resulting suspension, of organic or inorganic pigments, preferably chalk. The invention is also directed to the pulverulent product and its use, wherein the product is distinguished by good flow capacity and an extremely low methanol content. It is suitable for use as a binder in paper coating compositions and in coatings for the surface finishing of paper and cardboard.