Curable coating composition, method for making a coated metal plate having the coating composition and the coated metal plate made thereby

Abstract

A curable coating composition includes a polyester, a curing agent for curing the polyester, a curing catalyst, a composite solvent having at least two solvents with different dissolving powers for the polyester, and a wax incompatible with the polyester. A method for making a coated metal plate having an embossment-like texture formed from the coating composition, and the coated metal plate made thereby are also disclosed.

1 . A method for making a coated metal plate having an embossment-like texture, comprising the steps of: 
 (i) applying to a metal plate a polyester-based primer coating to form a base film;    (ii) applying a curable coating composition on said base file to form a top film, said curable coating composition including a polyester, a curing agent for curing said polyester, a curing catalyst, a composite solvent including at least two solvents having different dissolving powers for said polyester, and a was incompatible with said polyester, and a wax incompatible with said polyester; and    (iii) heating said metal plate after the step (ii) to cure said curable coating composition.    
   
   
       2 . The method as claimed in  claim 1 , wherein said polyester has a molecular weight ranging from 10000 to 20000, a hydroxyl value ranging from 10 to 40, and an acid value of no more than 5.  
   
   
       3 . The method as claimed in  claim 1 , wherein the step (iii) is conducted at a temperature ranging from 210 to 250° C.  
   
   
       4 . The method as claimed in claim  13 , wherein the time for heating in step (iii) ranges from 20 seconds to 5 minutes.  
   
   
       5 . The method as claimed in claim  13 , wherein said metal plate is selected from a group consisting of a copper plate, a galvanized steel plate, a galvalume steel plate, and a stainless steel plate.