Abstract: A sizing agent for paper consisting essentially of a latex consisting essentially of at least one diurethane dispersed in an aqueous medium, said diurethane being of the formula: ##STR1## in which: (a) R.sub.1, R.sub.2, R.sub.5 and R.sub.6 are each alkyl radicals and at least one of them possesses a minimum of 7 carbon atoms;(b) R.sub.7 and x represent, respectively, the cationic and anionic portions of the quaternizing agent R.sub.7 x;(c) R.sub.3 and R.sub.4 are selected from C.sub.2 -C.sub.4 alkylene radicals or polyalkoxylated radicals of a degree of polycondensation of between 1 and 4; and(d) Y is ##STR2## The process of making the sizing agent and using it to size paper are also disclosed.

Abstract: A sizing agent for paper consisting essentially of a latex consisting essentially of at least one diurethane dispersed in an aqueous medium, said diurethane being of the formula: ##STR1## in which: (a) R.sub.1, R.sub.2, R.sub.5 and R.sub.6 are each alkyl radicals and at least one of them possesses a minimum of 7 carbon atoms;(b) R.sub.7 and x represent, respectively, the cationic and anionic portions of the quaternizing agent R.sub.7 x;(c) R.sub.3 and R.sub.4 are selected from C.sub.2 -C.sub.4 alkylene radicals or polyalkoxylated radicals of a degree of polycondensation of between 1 an 4; and(d) Y is ##STR2## The process of making the sizing agent and using it to size paper are also disclosed.

Abstract: A sizing agent for the paper industry comprising a cationic oligourethane latex; said urethane having the formula: ##STR1## in which R.sub.2 is an alkylene radical containing a C.sub.2 -C.sub.6 radical or a polyoxyalkylenic radical of a degree of polycondensation of 1 to 4,R.sub.3 is an alkyl radical containing at least 7 carbon atoms, andR.sub.4 and X represent the remainder of the quaternizing agent R.sub.4 Xwith(a) R.sub.1 representing ##STR2## R.sub.5 being an aliphatic radical containing C.sub.4 as a maximum and n varying from 1 to 3; or(b) R.sub.1 representing ##STR3## R.sub.5 being ##STR4## in which R.sub.2, R.sub.3, R.sub.4 and X having the preceding definitions and n varying from 2 to 6; and the method of making the oligourethane latex.