Crosslinkable hydroxy terminated polydiene polymer coating compositions for use on substrates and a process for preparing them

Abstract

A crosslinkable composition for coating primed and unprimed substrates comprising from 10 to 80 percent by weight of a hydroxy functional polydiene polymer having a functionality of at least 1.3, 8 to 60 percent by weight of an amino resin crosslinking agent, and 2 to 40 percent by weight of a reinforcing agent. The invention also encompasses a process to make such compositions by partially reacting the three components for 0.5 to 10 hours at 60.degree. to 120.degree. C., optionally in the presence of a small amount of catalyst, to give phase stable compositions and subsequently completely crosslinking the composition by baking the composition on a substrate. The invention also encompasses a process for painting a substrate which comprises priming the substrate with a primer selected from the group consisting of epoxy resin primers and polyester resin primers, applying to the primed substrate a crosslinkable basecoat composition comprising from 10 to 80 percent by weight of a hydroxy functional polydiene polymer having a functionality of at least 1.3, from 8 to 60 percent by weight of an amino resin crosslinking agent, and from 2 to 40 percent by weight of a reinforcing agent, and applying over the basecoat a clearcoat selected from the group consisting of dihydroxy polydiene-based clearcoats, polyester clearcoats, and acrylic clearcoats.

Dependencies are inferred from the claim text.