Direct-to-metal coating composition

Abstract

A fast drying, heavy metal-free, high performance coating composition with outstanding UV resistance, and excellent corrosion resistance coupled with fast dry and long pot life. This coating can be applied over DTM, such as blasted cold rolled steel, or treated cold rolled steel, aluminum and treated aluminum. High corrosion resistance without sacrificing gloss or UV resistance achieved by selecting proper pigments and proper pigment design and packing by advantageously utilizing differing pigment morphologies (sizes and shape).

What is claimed is: 
     
         1 . A coating composition comprising: (a) a binder resin system; (b) a crosslinker resin; (c) a plurality of specialty pigments having pigment particles of various morphologies; and (d) a corrosion inhibiting pigment. 
     
     
         2 . The composition of  claim 1 , further comprising a color pigment. 
     
     
         3 . The composition of  claim 1 , wherein the specialty pigments are selected from a group consisting of filler pigments and extender pigments. 
     
     
         4 . The composition of  claim 1 , wherein the pigment volume concentration of the composition is between 10 to 80%. 
     
     
         5 . The composition of  claim 1 , wherein the pigment volume concentration of the composition is between 20 to 60%. 
     
     
         6 . The composition of  claim 1 , wherein the pigment volume concentration of the composition is between 25 to 45%. 
     
     
         7 . The composition of  claim 1 , wherein the corrosion inhibiting pigment comprises at least one non-toxic environmental friendly micronized cation-containing pigment. 
     
     
         8 . The composition of  claim 1 , wherein the corrosion inhibiting pigment is between 1 to 30 wt %, based on the total weight of the coating composition. 
     
     
         9 . The composition of  claim 1 , wherein the corrosion inhibiting pigment is between 2 to 20 weight percent based on the total weight of the coating composition. 
     
     
         10 . The composition of  claim 1 , wherein the corrosion inhibiting pigment is between 3 wt % to 15 wt %, based on the total weight of the coating composition. 
     
     
         11 . The composition of  claim 1 , wherein the corrosion inhibiting pigment comprises at least one micronized anodic passivating pigment. 
     
     
         12 . The composition of  claim 11 , wherein the micronized anodic passivating pigment is between 1 to 30 wt %, preferably between 2 wt % to 20 wt %, most preferably between 3 wt % to 15 wt %, based on the total weight of the coating composition. 
     
     
         13 . The composition of  claim 11 , wherein the micronized anodic passivating pigment is between 2 wt % to 20 wt %, based on the total weight of the coating composition. 
     
     
         14 . The composition of  claim 11 , wherein the micronized anodic passivating pigment is between 3 wt % to 15 wt %, based on the total weight of the coating composition. 
     
     
         15 . The composition of  claim 2 , wherein the color pigments comprise at least one organic or inorganic color pigment between 0.5 to 30 wt %, based on the total weight of the coating composition. 
     
     
         16 . The composition of  claim 1 , wherein the specialty pigments comprise at least three or more specialty extender pigments having differing particle sizes and shapes. 
     
     
         17 . The composition of  claim 1 , wherein the specialty pigments comprise: (a) at least one spherical shaped pigment; (b) at least one acicular shaped pigment; and (c) at least one platy shaped pigment. 
     
     
         18 . The composition of  claim 1 , wherein the specialty pigments comprise: (a) between 5 to 50 wt %, spherical shaped pigment ; (b) between 2 to 30 wt acicular shaped pigment; and (c) between 1 to 30 wt % platy-shaped pigment. 
     
     
         19 . The composition of  claim 1 , wherein the specialty pigments comprise: (a) between 10 to 30 wt %, spherical shaped pigment; (b) between 3 to 20 wt % acicular shaped pigment; and (c) between 3 to 20 wt % platy-shaped pigment. 
     
     
         20 . The composition of  claim 1 , wherein the specialty pigments comprise: (a) between 15 to 25 wt % spherical shaped pigment; (b) between 4 to 12 wt % acicular shaped pigment; and (c) between 4 to 12 wt % platy-shaped pigment. 
     
     
         21 . The composition of  claim 1 , wherein the specialty pigments comprise: (a) at least one spherical shaped pigment; (b) at least one acicular shaped pigment; and (c) at least one platy-shaped pigment; wherein said specialty pigments have median particle size between 0.1 to 20 μm. 
     
     
         22 . The composition of  claim 1 , wherein the specialty pigments have median particle size between 0.1 to 10 μm. 
     
     
         23 . The composition of  claim 1 , wherein the specialty pigments have median particle size between 0.3 to 6 μm. 
     
     
         24 . The composition of  claim 1 , wherein the binder system comprises one or more resins selected from the group consisting of: (a) malonate-functional donor resin between 10 to 50 wt %; (b) one or more acrylic or polyester polyol resin between 10 to 50 wt %; and
 (c) one or more aspartic ester resin between 10 to 50 wt %; and (d) one or more alkyd or modified alkyd resin between 10 to 50 wt %, based on the total weight of the coating composition.   
     
     
         25 . The composition of  claim 1 , wherein the binder system comprises one or more resins selected from the group consisting of: (a) malonate-functional donor resin between 15 to 35 wt %; (b) one or more acrylic or polyester polyol resin between 15 to 40 wt %; and (c) one or more aspartic ester resin between 15 to 35 wt %; and (d) one or more alkyd or modified alkyd resin between 20 to 45 wt %, based on the total weight of the coating composition. 
     
     
         26 . The composition of  claim 1 , wherein the binder system comprises one or more resins selected from the group consisting of: (a) malonate-functional donor resin between 20 to 35 wt %; (b) one or more acrylic or polyester polyol resin between 18 to 30 wt %; and (c) one or more aspartic ester resin between 20 to 25 wt %; and (d) one or more alkyd or modified alkyd resin between 30 to 35 wt %, based on the total weight of the coating composition. 
     
     
         27 . The composition of  claim 1 , wherein the binder system comprises one or more malonate-functional resin between 10 to 50 wt %, and the crosslinker resin comprise of one or more acryloyl acceptor resin between 5 to 40 wt %, based on the total weight of the coating composition. 
     
     
         28 . The composition of  claim 1 , wherein the binder system comprises one or more malonate-functional resin between 15 to 35 wt %, and the crosslinker resin comprises one or more acryloyl acceptor resin between 6 to 25 wt %, based on the total weight of the coating composition. 
     
     
         29 . The composition of  claim 1 , wherein the binder system comprises one or more malonate-functional resin between 20 to 35 wt % and the crosslinker resin comprise of one or more acryloyl acceptor resin between 8 to 15 wt %, based on the total weight of the coating composition. 
     
     
         30 . The composition of  claim 1 , wherein the binder system is selected from the group consisting of one or more acrylic resin, polyester polyol resin, and aspartic ester resin, and the crosslinker resin comprises one or more aliphatic isocyanate resin between 5 to 40 wt %. 
     
     
         31 . The composition of  claim 1 , wherein the binder system is selected from the group consisting of one or more acrylic resin, polyester polyol resin, and aspartic ester resin, and the crosslinker resin comprises one or more aliphatic isocyanate resin between 8 to 25 wt %. 
     
     
         32 . The composition of  claim 1 , wherein the binder system is selected from the group consisting of one or more acrylic resin, polyester polyol resin, and aspartic ester resin, and the crosslinker resin comprises one or more aliphatic isocyanate resin between 10 to 18 wt %. 
     
     
         33 . The composition of  claim 1 , wherein the binder system comprises one or more cycloaliphatic epoxy resin between 10 to 50 wt %, and wherein the crosslinker system comprises one or more amines between 5 to 50 wt %, based on the total weight of the coating composition. 
     
     
         34 . The composition of  claim 1 , wherein the binder system comprises one or more cycloaliphatic epoxy resin between 15 to 35 wt %, and wherein the crosslinker system comprises one or more amines between 10 to 35 wt %, based on the total weight of the coating composition. 
     
     
         35 . The composition of  claim 1 , wherein the binder system comprises one or more cycloaliphatic epoxy resin between 18 to 22 wt %, and wherein the crosslinker system comprise one or more amines between 20 to 28 wt %, based on the total weight of the coating composition 
     
     
         36 . The composition of  claim 1 , further comprising an adhesion promoting component selected from the group consisting of: (a) at least one liquid epoxy resin between 0.5 to 15 wt %; and (2) at least one amino silane between 0.2 to 15 wt, based on the weight of the total coating composition. 
     
     
         37 . The composition of  claim 1 , further comprising an adhesion promoting component selected from the group consisting of: (a) at least one liquid epoxy resin between 1 to 10 wt %; and (2) at least one amino silane between 0.5 to 10 wt %, based on the weight of the total coating composition. 
     
     
         38 . The composition of  claim 1 , further comprising an adhesion promoting component selected from the group consisting of: (a) at least one liquid epoxy resin between 2 to 6 wt %; and (2) at least one amino slime between 1 to 5 wt %, based on the weight of the total coating composition. 
     
     
         39 . A coated metal substrate, comprising:
 (a) a metal substrate;   (b) a coating composition on the surface of the metal substrate, said coating composition comprising:   (a) a binder resin system;   (b) a crosslinker resin;   (c) a plurality of specialty pigments having pigment particles of various morphologies; and   (d) a corrosion inhibiting pigment.   
     
     
         40 . The composition of  claim 1 , wherein the coating composition is applied to a substrate using conventional spray, air assisted airless, or electrostatic spraying techniques. 
     
     
         41 . The coating composition of  claim 1 , wherein the coating has an excellent corrosion and weathering resistance.