Low reflectance powder coated article

Abstract

A low reflectance powder coated article comprising a substrate having thereon a low gloss acrylic powder coating made from: (a) a first acrylic powder resin having a hydroxyl value of at least about 180; (b) a second acrylic powder resin having a hydroxyl value between about 45 and about 80; (c) a crosslinker reactive with the hydroxyl functional acrylic resins; and (d) an acicular filler.

We claim: 
     
         1 . A low reflectance powder coated article comprising a substrate having thereon a low gloss acrylic powder coating made from:
 (a) a first hydroxyl functional acrylic powder resin having a hydroxyl value of at least about 180;   (b) a second hydroxyl functional acrylic powder resin having a hydroxyl value between about 45 and about 80;   (c) a crosslinker reactive with the first and second hydroxyl functional acrylic resins; and   (d) an acicular filler;   
     
     
         2 . The powder coated article of  claim 1  wherein the substrate comprises a military article. 
     
     
         3 . The powder coated article of  claim 1  wherein the substrate comprises a firearm. 
     
     
         4 . The powder coated article of  claim 1  wherein the coating is resistant to penetration by chemical warfare agents according to military specification MIL-PRF-32348. 
     
     
         5 . The powder coated article of  claim 1  wherein the substrate comprises an automotive interior part. 
     
     
         6 . The powder coated article of  claim 1  wherein the substrate comprises a wheel rim or bumper. 
     
     
         7 . The powder coated article of  claim 1  wherein the coating has a 60° gloss less than 1 and an 85° gloss of 3.5 or less. 
     
     
         8 . The powder coated article of  claim 1  wherein the first acrylic powder resin has a hydroxyl value of about 250. 
     
     
         9 . The powder coated article of  claim 1  wherein the second acrylic powder resin has a hydroxyl value of about 60. 
     
     
         10 . The powder coated article of  claim 1  wherein the first acrylic powder resin and the second acrylic powder resin each have a Tg of at least 35° C. 
     
     
         11 . The powder coated article of  claim 1  wherein the first acrylic powder resin has a Tg of at least 45° C. 
     
     
         12 . The powder coated article of  claim 1  wherein the first acrylic polymer wherein the weight ratio of the first acrylic powder resin to the second acrylic powder resin is at least 0.5. 
     
     
         13 . The powder coated article of  claim 1  wherein the first acrylic polymer is present at a level to provide between about 33.3 weight percent and 85.1 weight percent of the total combined weight of the first acrylic polymer and the second acrylic polymer. 
     
     
         14 . The powder coated article of  claim 1  wherein the first acrylic polymer is present at a level to provide between about 33.3 weight percent and 66.6 weight percent of the total combined weight of the first acrylic polymer and the second acrylic polymer. 
     
     
         15 . The powder coated article of  claim 1  wherein the acicular filler comprises wollastonite. 
     
     
         16 . The powder coated article of  claim 1  wherein the acicular filler is present at a level of at least 10% by weight solids of the coating composition. 
     
     
         17 . The powder coated article of  claim 1  wherein the acicular filler is present at a level of at least 15% by weight solids of the coating composition. 
     
     
         18 . The powder coated article of  claim 1  wherein the acicular filler is present at a level of at least 25% by weight solids of the coating composition. 
     
     
         19 . The powder coated article of  claim 1  wherein the crosslinker comprises an isocyanate compound. 
     
     
         20 . The powder coated article of  claim 1  wherein the coating further comprises a pigment selected from titanium dioxide, metallic pigment, iron oxides, carbon black or an organic pigment.