Polymeric resin, and its production and use

An aqueous emulsion comprising water and a polymeric resin, said emulsion having a viscosity of from 10 to 50,000 cps at 25.degree. C. and a polymeric resin content of from 2 to 65% by weight, said polymeric resin being prepared by a process which comprises polymerizing (a) at least one amino acid of either one of the formulae Ia and Ib:

• ##STR11## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each hydrogen, methyl or ethyl, R.sub.5 is hydrogen or C.sub.1 -C.sub.20 alkyl optionally having at least one of --SO--, --COO-- and --O-- in the alkyl chain, R.sub.6 is C.sub.1 -C.sub.12 alkylene optionally substituted with one or more of --OH, --SH, --SR.sub.7 (wherein R.sub.7 is C.sub.1 -C.sub.4 alkyl) and C.sub.1 -C.sub.4 alkyl, or phenylene optionally substituted with one or more of C.sub.1 -C.sub.4 alkyl, and A is --COOH or --SO.sub.3 H;
• ##STR12## wherein R.sub.8, R.sub.9 and R.sub.10 are each hydrogen or C.sub.1 -C.sub.6 alkyl, R.sub.11 is hydrogen, C.sub.1 -C.sub.20 alkyl optionally having at least one of --SO--, --COO-- and --O-- in the alkyl chain, or a group of the formula ##STR13## (wherein R.sub.8, R.sub.9 and R.sub.10 are each as defined above), R.sub.12 is C.sub.2 -C.sub.12 alkylene optionally substituted with one or more C.sub.1 -C.sub.6 alkyl, or phenylene optionally substituted with one or more C.sub.1 -C.sub.4 alkyl, and A is as defined above, with (b) at least one other polymerizable monomer, in an aqueous medium, the component (a) and at least a portion of the component (b) being introduced separately into the reaction system.