Near infrared electromagnetic radiation absorbing composition and method of use

Abstract

The present invention relates to liquid coating compositions that absorb near infrared electromagnetic radiation. The coating compositions include a near infrared absorbing agent, a carrier vehicle, and a solvent system. The invention is also directed to a method of reducing the reflection of near infrared radiation from a surface in which a liquid coating composition comprising a near infrared absorbing agent, a carrier vehicle, and a solvent system is applied to the surface and the solvent system is removed, leaving a coating with a thickness of about 0.25 mils to 2 mils. The present invention further relates to a surface having a coating comprised of a near infrared absorbing compound and a carrier vehicle.

1 - 19 . (canceled)  
     
     
         20 . A method of reducing the reflection of near infrared radiation from a surface, comprising: 
 (a) applying to the surface, a liquid composition comprising: 
 (i) a near infrared absorbing agent;  
 (ii) a carrier vehicle; and  
 (ii) a solvent system; and  
   (b) removing the solvent system, whereby a near-infrared absorbent coating is provided on the surface.    
     
     
         21 . The method of  claim 20 , wherein the solvent system is removed by evaporation.  
     
     
         22 . The method of  claim 20 , wherein the coating has a thickness of about 0.25 mil to about 2 mil.  
     
     
         23 . The method of  claim 20 , wherein the coating is capable of absorbing greater than about 99% of radiation with wavelength of about 885-920 nm incident upon the coating.  
     
     
         24 . The method of  claim 20 , wherein the near infrared absorbing agent is selected from the group consisting of compounds of the formula (I):  
         [(R 2 N Z ) 2 N=Z′=NR 2 ] 2+ +2X −   (I)  
       wherein R is an alkyl group of about 1 to about 6 carbon atoms; Z is a divalent phenyl which may or may not be ring substituted with one or more alkyl, alkoxy, halogen, nitro, cyano, and carboalkoxy groups; Z′ is a quinoidal phenyl which may or may not be ring substituted with one or more alkyl, alkoxy, halogen, nitro, cyano, and carboalkoxy groups; and X is an anion of a strong acid, and 
 compounds of the formula (II):  
   [(R 2 NZ) 3 N] + +X −   (II)  
 wherein R is an alkyl group of about 1 to about 6 carbon atoms; Z is a divalent phenyl which may or may not be ring substituted with one or more alkyl, alkoxy, halogen, nitro, cyano, and carboalkoxy groups; and X is an anion of a strong acid.  
 
     
     
         25 . A surface having a coating with a thickness of about 0.25 mil to about 2 mil, comprising: 
 (a) a near infrared absorbing agent; and    (b) a carrier vehicle,    wherein the thickness is measured in a direction transverse to the surface.    
     
     
         26 . A copolymer useful as a carrier vehicle, said copolymer prepared by polymerizing: 
 (a) about 45% to about 55% by weight butyl acrylate,    (b) about 38% to about 45% by weight methylmethacrylate,    (c) about 4% to about 10% by weight hydroxyethylmethacrylate,    (d) about 0% to about 8% by weight methacrylic acid, and    (e) about 0% to about 2% by weight acrylic acid.    
     
     
         27 . A copolymer useful as a carrier vehicle, said copolymer prepared by polymerizing: 
 (a) about 40% to about 70% by weight methylmethacrylate,    (b) about 10% to about 30% by weight ethylacrylate,    (c) about 20% to about 30% by weight dimethylaminoethylmetacrylate.    
     
     
         28 . A method of producing a copolymer useful as a carrier vehicle, said method comprising polymerizing: 
 (a) about 45% to about 55% by weight butyl acrylate,    (b) about 38% to about 45% by weight methylmethacrylate,    (c) about 4% to about 10% by weight hydroxyethylmethacrylate,    (d) about 0% to about 8% by weight methacrylic acid, and    (e) about 0% to about 2% by weight acrylic acid.    
     
     
         29 . A method of producing a copolymer useful as a carrier vehicle, said method comprising polymerizing: 
 (a) about 40% to about 70% by weight methylmethacrylate,    (b) about 10% to about 30% by weight ethylacrylate,    (c) about 20% to about 30% by weight dimethylaminoethylmetacrylate.