Hydrophile polyurethane foam, process for preparing said foam and hydrophile product based on said foam

Claim 1

A process for preparing a hydrophile polyurethane foam absorption material for medical and hygienic use comprising reaction of hydrophile polyol, a polyisocyanate wherein NCO groups are not directly bonded to an aromatic ring, a foam stabilizer, a swelling agent and an effective amount of a catalyst, wherein the catalyst consists essentially of: (A) at least one compound selected from the group consisting of (1)diazabicycloalkenes of the formula: ##STR23## wherein m varies from 3 to 7 and n from 2 to 4, and salts thereof with organic acids the dissociation constant of which is Ka≦10 -2 ; (2) substituted guanidines and salts thereof of the formula: ##STR24## wherein R 1 , R 2 , R 3 and R 4 can independently represent a C 1 -C 4 alkyl radical, a C 1 -C 4 alkyl radical substituted by a C 1 -C 4 alkoxy radical, or a heterocyclic C 5 -C 7 radical comprising at most two atoms from the group consisting of sulfur and oxygen, R 1 and R 2 and/or R 3 and R 4 may form with the adjacent nitrogen a heterocyclic C 5 -C 7 ring containing at most one member from the group consisting of sulfur or oxygen atom, X represents a member selected from the group consisting of hydrogen, phenyl, a phenyl group substituted by one or more C 1 -C 4 alkoxy radicals, C 1 -C 12 alkyl radicals or halogens, or represents a radical of the formula: ##STR25## wherein R 5 , R 6 and R 7 can independently represent hydrogen, a C 1 -C 4 alkyl radical or a C 1 -C 4 alkyl radical substituted by a member selected from the group consisting of phenyl, substituted phenyl, C 1 -C 4 alkoxy, C 6 -C 15 aryloxy, nitrile or carbalkoxy, or R 7 may represent a member selected from the group consisting of a C 5 -C 18 alkyl radical, a substituted phenyl radical or a C 1 -C 4 alkoxy radical; or one or two of the groups R 5 -R 6 , R 5 -R 7 or R 6 -R 7 can form a cyclic ring of more than one member selected from the group consisting of nitrogen, sulfur or oxygen atom, and X may also represent a radical of the formula: ##STR26## wherein z is an integer of from 2 to 12, R' and R" represent a member selected from the group consisting of hydrogen or a C 1 -C 4 alkyl radical, R''' and R'''' represent a member selected from the group consisting of a C 1 -C 4 alkyl radical or form with the adjacent nitrogen of a C 5 -C 6 cycloalkyl radical; and addition salts of said guanidines; and addition salts of guanidines; (3) substituted biguanidines of the formula: ##STR27## wherein Q 1 to Q 6 can independently represent a member selected from the group consisting of C 1 -C 4 alkyl or a C 3 -C 4 cycloalkyl radical, and X' is hydrogen or a carbamoyl radical of the formula: ##STR28## in which Z is a monovalent radical remaining after elimination of an isocyanate group from the above mentioned polyisocyanate, Q 1 to Q 6 , X' and Z may optionally be substituted by a member selected from the group consisting of chlorine, bromine or a C 1 or C 2 alkoxy radical; and (4 ) substituted biguanidines of the formula: ##STR29## wherein M 1 to M 8 can independently represent a C 1 -C 4 alkyl radical, Y represents a group of the formula: ##STR30## wherein M 9 and M 10 represent a member selected from the group consisting of hydrogen or a C 1 -C 4 alkyl radical, and α is an integer from 3 to 12 or represents a divalent cyclohexyl or a divalent isophorene radical; and (B) at least one alkali or alkaline earth metal salt of an organic acid having a dissociation constant Ka≦10 -1 .