| 摘要 |
<p>A primer/topcoat coil coating system employs crosslinkable branched hydroxyl-functional polyester-imide resins derived or derivable from a symmetric aromatic imide triol and a diacid or acid-producing derivative. The primer resin has a hydroxyl number greater than about 90 but not more than about 215, the topcoat resin has a hydroxyl number greater than about 100 but not more than about 215, and the primer and topcoat can each be hardened in 30 seconds or less to provide a coating having at least OT flexibility with no tape off and at least 2H pencil hardness.</p> |
