Patent ID: 8512520

Claim:
A paper size obtained by dispersing a reactive size comprising a) a stable aqueous dispersion of 5 to 35% by weight, based on the total weight of the dispersion, of a reactive size which is C 12 to C 22 alkylketene dimers, b) from 10 to 50% by weight, based on the reactive size, of a substantially linear polyvinylamine having a Fikenstscher K-value of from 45 to 50 and a degree of hydrolysis of from 70 to 100 mol %, c) from 3 to 20% by weight, based on the reactive size, of a cationic starch having a degree of substitution of 0.1 to 0.2, and d) an anionic dispersant wherein the paper size is prepared by a process, in which i) an aqueous solution of the cationic starch and of the ionic dispersant is initially mixed together, ii) subsequently, the reactive size and the vinylamine polymer are added in any desired sequence, and iii) the mixture obtained is subjected to dispersing, and wherein the dispersion remains in fluid form after 4 weeks at 40° C.