Dry film lubricant

Abstract

The present invention relates to compositions and methods employing a first copolymer that is an acrylic copolymer or styrene/acrylic copolymer having a weight average molecular weight (Mw) of about 8,000 to about 14,000; a second copolymer that is an acrylic copolymer having a Mw of about 90,000 to about 130,000; a wax emulsion or dispersion, and a particulate additive. Optionally, the composition further comprises at least one of a rheological additive, ammonium hydroxide or a defoaming compound.

1 . A composition, comprising: 
 a first copolymer that is an acrylic copolymer or styrene/acrylic copolymer having a weight average molecular weight (Mw) of about 8,000 to about 14,000;    a second copolymer that is an acrylic copolymer having a Mw of about 90,000 to about 130,000;    water;    a wax emulsion and/or wax dispersion; and    a particulate additive.    
   
   
       2 . The composition of  claim 1 , wherein said first copolymer is present in a range from about 10 to about 23 percent by weight of the composition.  
   
   
       3 . The composition of  claim 1 , wherein said second copolymer is present in a range from about 30 to about 70 percent by weight of the composition.  
   
   
       4 . The composition of  claim 1 , wherein said water is present in a range from about 5 to about 30 percent by weight of the composition.  
   
   
       5 . The composition of  claim 1  additionally comprising a rheological additive.  
   
   
       6 . The composition of  claim 1 , wherein said theological additive is modified urea in N-methyl pyrrolidine and is present in a range from about 0.1 to about 1 percent by weight of the composition.  
   
   
       7 . The composition of  claim 1  comprising a wax emulsion that comprises paraffin and polyethylene.  
   
   
       8 . The composition of  claim 7 , wherein said wax emulsion is present in a range from about 3 to about 18 percent by weight of the composition.  
   
   
       9 . The composition of  claim 1 , wherein said particulate additive is a silicate.  
   
   
       10 . The composition of  claim 1 , wherein said particulate additive is a silicate including at least one of Al or Mg.  
   
   
       11 . The composition of  claim 1 , wherein said particulate additive is talc.  
   
   
       12 . The composition of  claim 11 , wherein said talc is present in a range from about 0.01 to about 4 percent by weight of the composition.  
   
   
       13 . A coating comprising the composition of  claim 1 .  
   
   
       14 . A substrate contacted by the composition of  claim 1 , wherein the substrate is stainless steel, galvanized steel, hot dipped galvanized steel, electro galvanized steel, galvanneal alloy, alloy steel comprising 55% aluminum, 43.5% zinc, and 1.5% silicon, cold rolled steel, hot rolled steel, or aluminum.  
   
   
       15 . A method for reducing blocking between substrates, comprising contacting said substrates with the composition of  claim 1 .  
   
   
       16 . The method of  claim 15  wherein the coating is dried using surface temperatures lower than about 200° F., and as low as about 170° F.  
   
   
       17 . A composition, comprising: 
 a first copolymer that is an acrylic copolymer or styrene/acrylic copolymer having a weight average molecular weight (Mw) of about 8,000 to about 14,000;    a second copolymer that is an acrylic copolymer having a Mw of about 90,000 to about 130,000;    water;    a wax emulsion;    a particulate additive; and    a viscosity builder.    
   
   
       18 . A composition, comprising: 
 a styrene/acrylic copolymer colloidal dispersion;    a thermoplastic acrylic copolymer colloidal dispersion;    water;    a urea-containing rheological additive;    a wax emulsion;    a silicate including at least one of Mg or Al; and    ammonium hydroxide.    
   
   
       19 . The composition of  claim 18 , further comprising a defoaming compound.  
   
   
       20 . The composition of  claim 18 , wherein said silicate is talc.