The invention relates to a fast hardening aqueous coating composition comprising from about 95 to about 99 weight percent of an anionically stabilized aqueous emulsion of a copolymer having a Tg of from about 0° C. to about 40° C., the copolymer containing two or more ethylenically unsaturated monomers, wherein from 0 to about 4 weight percent of the monomers are &agr;,&bgr;-ethylenically unsaturated aliphatic carboxylic acid monomers; from about 0.2 to about 5 weight percent of a polyimine having a molecular weight of from about 250 to about 20,000; and from about 0.2 to about 5 weight percent of a volatile base, wherein the composition has a pH from about 8 to about 11, and wherein a cast film of the composition has a hardening rate measurement rating of at least 5 within 20 minutes after casting under ambient conditions of temperature up to 30° C. and relative humidity no less than 50 percent. Within the scope of the invention are a process for the preparation of a fast hardening aqueous coating composition, a fast hardening aqueous traffic paint, and a fast hardening migration resistant binder for composites.