Reactive oligomers for isocyanate coatings

A process for producing a coating on the surface of a substrate, said process comprising:

• mixing hydroxyl and crosslinking components of a binder of an ambient coating composition to form a potmix, wherein said hydroxyl component comprises a linear or branched cycloaliphatic moiety-containing reactive oligomer having a GPC weight average molecular weight not exceeding 3,000 and a polydispersity not exceeding about 1.7, said reactive oligomer having at least two hydroxyl groups, at least one of which on average being a primary hydroxyl group, said oligomer being produced by reacting an oligomeric acid with a monofunctional epoxy selected from the group consisting of ethylene oxide, butylene oxide, propylene oxide, and a combination thereof, and wherein said crosslinking component comprising an oligomeric crosslinker provided with at least two isocyanate groups wherein the ratio of equivalents of isocyanate per equivalent of hydroxyl groups is in the range of from 0.5/1 to 3.0/1;
• applying a layer of said pot mix on said surface;
• and
• curing said layer under ambient conditions to form said coating on said surface of said substrate.