Primer composition for promoting adhesion of a urethane adhesive to a polymeric substrate

Abstract

There is disclosed a primer composition for promoting adhesion between a polymeric substrate and an adhesive. The primer composition may include, without limitation, a resin, an isocyanate, a catalyst, a solvent and optionally an optical brightener.

1 . A method for priming a surface for a urethane adhesive, comprising the steps of: 
 providing a primer composition comprising: 
 a polyester resin wherein the resin is present in an amount of about 2 to about 10 parts by weight of the primer composition;  
 an isocyanate in an amount of about 3 to about 30 parts by weight of the primer composition;  
 a catalyst in an amount up to about 2 parts by weight of the primer composition; and  
 a solvent; and  
   contacting the primer composition with a substrate, wherein the substrate is made of plastic or comprises a polymeric component as a major component.    
     
     
         2 . The method of  claim 1 , further comprising: 
 contacting a urethane adhesive with the primer composition.    
     
     
         3 . The method of  claim 2 , further comprising: 
 adhering the urethane adhesive to a second substrate.    
     
     
         3 . A method as in  claim 3 , wherein the second substrate is an automotive vehicle body member.  
     
     
         4 . The method of  claim 1 , wherein at least a portion of the resin is a methacrylate.  
     
     
         5 . A method as in  claim 1 , wherein at least a portion of the isocyanate is a thiophosphate with an isocyanate group.  
     
     
         6 . The method of  claim 1 , wherein the primer composition includes an agent for allowing detection of the primer composition on the substrate, the detection agent present in about 0.001 to about 1 parts by weight of the primer composition.  
     
     
         7 . The method of  claim 1 , wherein the plastic or polymeric component is selected from a thermoplastic, a thermoset, an elastomer, a plastomer, or combinations thereof.  
     
     
         8 . The method of  claim 7 , wherein the plastic or polymeric component is selected from a polyvinylchloride or a reaction-injection molded polyurethane.  
     
     
         9 . The method of  claim 8 , wherein the plastic or polymeric component further comprises a high solid content, a high plasticizer content, a mold release agent or combinations thereof.  
     
     
         10 . A method for bonding a plastic substrate at least partially encapsulating a transparent sheet, comprising the steps of: 
 providing a transparent sheet assembly including a transparent sheet at least partially encapsulated with a plastic seal;    contacting the plastic seal with a primer composition comprising: 
 a polyester resin wherein the resin is present in an amount up to about 10 parts by weight of the primer composition;  
 an isocyanate in an amount up to about 3 to about 30 parts by weight of the primer composition;  
 a catalyst in an amount of about 0.05 to about 2 by weight of the primer composition; and  
 a solvent;  
   contacting the primer composition with a polyurethane adhesive; and    contacting the polyurethane adhesive with an automotive vehicle member for bonding the transparent sheet assembly to the automotive vehicle member, wherein the automotive vehicle member is made of plastic or comprises a polymeric component as a major component.    
     
     
         11 . The method of  claim 10 , wherein at least a portion of the resin is a methacrylate.  
     
     
         12 . The method of  claim 10 , wherein at least a portion of the isocyanate is a thiophosphate with an isocyanate group.  
     
     
         13 . The method of  claim 10 , wherein the primer composition includes an agent for allowing detection of the primer composition on the substrate, the detection agent present in about 0.001 to about 1 parts by weight of the primer composition.  
     
     
         14 . The method of  claim 1 , wherein the plastic or polymeric component is selected from a thermoplastic, a thermoset, an elastomer, a plastomer, or combinations thereof.  
     
     
         15 . The method of  claim 14 , wherein the plastic or polymeric component is selected from a polyvinylchloride or a reaction-injection molded polyurethane.  
     
     
         16 . The method of  claim 15 , wherein the plastic or polymeric component further comprises a high solid content, a high plasticizer content, a mold release agent or a combination thereof.  
     
     
         17 . The method of  claim 10 , wherein the automotive vehicle body member is a body panel.  
     
     
         18 . The method of  claim 10 , wherein the transparent sheet is a windshield of an automotive vehicle  
     
     
         19 . The method of  claim 10 , wherein at least a portion of the solvent is methyl ethyl ketone.