Abstract: There is disclosed a method for sizing paper by adding to the surface of the paper a sizing composition comprising cellulose reactive and cellulose non-reactive size. The sized paper performs better in ink jet printing than does paper that is the same except that the size composition contains only cellulose reactive size or only cellulose non-reactive size, when the printing is evaluated for at least one property selected from the group consisting of optical density, feathering, wicking, edge roughness and bleed. The sized paper also has higher toner adhesion, a higher coefficient of friction and a lower coefficient of friction bandwidth than does paper that is the same except that the size composition contains only cellulose reactive size. The paper is also capable of performing effectively in tests that measure its convertibility on state-of-the-art converting equipment and its performance on high speed end-use machinery.

Abstract: Compositions and methods useful stabilizing dispersions containing paper sizing agents are provided. The dispersions comprise a hydrophobically modified water-soluble polymer having a viscosity average molecular weight less than about 200,000. Dispersions containing sizing agents and other agents for treating paper can be made according to the methods of the invention.

Abstract: A process for preparing sized paper which incorporates in the paper a size composition containing polymer latex, wherein the polymer contained in the polymer latex is anionic polymer having properties selected from the group consisting of T.sub.G about -15.degree. C. to about 50.degree. C. and acid number about 30 to about 100, and wherein the polymer latex has a zeta potential of from about -25 to about -70 millivolts over the pH range of about 5 to about 9. A preferred process has the steps: a) providing an aqueous pulp suspension; b) sheeting and drying the aqueous pulp suspension to obtain paper; c) treating the paper by applying to at least one surface of it the size composition containing polymer latex and starch; and d) drying the paper to obtain sized paper. Preferred anionic polymers are copolymers of monomers comprising styrene or substituted styrene, alkyl acrylate or methacrylate and ethylenically unsaturated carboxylic acid.