Abstract: Dry finished coated paperboard is prepared with a smoothness and printability substantially equivalent to a comparable wet finished product, and without significant loss of bulk, with the addition of a plasticizing agent to the surface sizing formulation prior to calendering and before coating. The plasticizing agent preferably has a boiling point greater than water and is soluble in water. In addition, the surface size treatment is preferably applied with a blade, gateroll or like arrangement so that the plasticizing agent remains substantially on the surface of the paperboard with little or no penetration.

Abstract: A white, bright and opaque urea formaldehyde pigment is prepared in a continuous process by precipitating a urea formaldehyde resin or prepolymer having a relatively low water tolerance and a relatively high viscosity in an aqueous precipitating bath containing an acid catalyst. The reaction is carried out by supplying the urea formaldehyde resin to one or more reactors each containing the precipitating bath at an elevated temperature and under agitation, wherein a precipitate begins to form almost immediately. The reaction is allowed to progress for a length of time sufficient to permit most of the higher molecular weight fractions of the resin to precipitate out, the precipitate is then filtered preferably at the reaction temperature, washed and collected.