Preparation of cross-linked particles of polyurethane or polyurea containing ionic groups

Claim 2

A PROCESS FOR THE PREPARATION OF SEDIMENTING AND REDISPERSIBLE CROSS-LINKED PARTICLES, SAID PARTICLES BEING INSOLUBLE IN DIMETHYL FORMAMIDE AND CONTAINING UREA GROUPS WHICH COMPRISES DISPERSING A POLYURETHANE OR A POLYUREA POLYMER CONTAINING FREE NCO GROUPS AND FROM ABOUT 0.001 TO ABOUT 0.2 EQUIVALENT PER CENT OF AN IONIC GROUP SELECTED FROM THE GROUP CONSISTING OF

Claim 3

A process for the preparation of sedimenting and redispersible cross-linked particles, said particles being insoluble in dimethyl formamide and containing urea groups which comprises dispersing a polyurethane or a polyurea polymer containing free NCO groups and from about 0.001 to about 0.2 equivalent per cent of an ionic group selected from the group consisting of

Claim 4

A process for the preparation of sedimenting and redispersible cross-linked particles, said particles being insoluble in dimethyl formamide and containing urea groups which comprises dispersing a polyurethane or a polyurea polymer containing free NCO groups and from about 0.001 to about 0.2 equivalent per cent of an ionic group selected from the group consisting of

Claim 5

The product prepared by the process of claim 1.

Claim 6

The process of claim 1 wherein the polyurethane or polyurea contains from about 0.001 to about 0.2 equivalent per cent of quaternized nitrogen atoms.

Claim 7

The process of claim 1 wherien the polyurethane polymer containing free NCO groups is prepared by reacting in the first step an organic compound containing two active hydrogen atoms as determined by the Zerewitinoff methOd and having a molecular weight of from about 300 to 10,000 with an excess of an organic diisocyanate to prepare an essentially linear polyurethane having two free NCO groups and reacting the product of said first step in the second step with a chain extending agent which contains said ionic group in an amount sufficient to include from about 0.001 to about 0.2 equivalent per cent of said salt-type group into said polyurethane.

Claim 8

The process of claim 4 wherein said chain extending agent is a low molecular weight glycol containing a basic tertiary amino group which is reacted subsequent to chain extension of the isocyanato polyurethane with an inorganic acid.

Claim 9

The process of claim 1 wherein the molar ratio of the amino groups in the water solution to the isocyanato groups in the urethane or urea polymer is from about 0.1:1 to about 1.8:1.

Claim 10

The process of claim 1 wherein the polyurethane or polyurea polymer is prepared by reacting an organic polyisocyanate with an organic compound having a molecular weight of from about 300 to about 10,000 and containing active hydrogen groups as determined by the Zerewitinoff method, said reactants being present in amounts such that the NCO to active hydrogen atom ratio is from 4:1 to 1.1:1.