Near infrared absorbing acrylic construction blocks

Abstract

Acrylic construction blocks in which the faces absorb infrared radiation and transmit visible radiation are disclosed. The faces each comprise an effective amount of an infrared absorber that comprises an infrared absorbing phthalocyanine compound. The blocks may be used in applications in which it is desirable to filter out the infrared radiation passing through the acrylic blocks without materially diminishing the transmission of visible radiation.

1 . An acrylic construction block comprising a body having a pair of faces joined by a plurality of side edges normal to the faces, each face and side edge having an inner surface and an outer surface, the faces and edge sides defining an interior chamber; in which 
 each of the faces comprises an acrylic resin and an effective amount of an infrared absorber; and    the infrared absorber comprises an infrared absorbing phthalocyanine compound represented by the following structure:                          in which Z 1  to Z 16  each independently represent SR 1 , OR 2 , a hydrogen atom, a halogen atom, or NHY where Y independently represents a phenyl group which may have one or more substituents selected from the group consisting of 1 to 3 alkyl groups having 1 to 4 carbon atoms, 1 to 2 alkoxy groups having 1 to 4 carbon atoms, 1 to 2 alkoxycarbonyl groups having 1 to 8 carbon atoms, and 1 to 5 halogen atoms, or an alkyl group having 1 to 8 carbon atoms; R 1  and R 2  independently represent a phenyl group which may have one or more substituents selected from the group consisting of 1 to 3 alkyl groups having 1 to 4 carbon atoms, 1 or 2 alkoxy groups having 1 to 4 carbon atoms, 1 or 2 alkoxycarbonyl group having 1 to 4 carbon atoms, 1 or 2 alkoxycarbonyl group having 1 to 8 carbon atoms and 1 to 5 halogen atoms or an alkyl group having 1 to 20 carbon atoms; and M represents metal, metal oxide, metal halide or two hydrogen atoms; provided that at least one of Z 1  to Z 16  is NHY.    
     
     
         2 . The acrylic construction block of  claim 1  in which at least four of Z 1  to Z 16  are fluorine.  
     
     
         3 . The acrylic construction block of  claim 1  in which M is VO, four to eight of Z 1  to Z 16  are C 6 H 5 NH, and the remaining eight to twelve of Z 1  to Z 16  are fluorine.  
     
     
         4 . The acrylic construction block of  claim 1  in which the infrared absorbing phthalocyanine compound is CAS #189326-16-7.  
     
     
         5 . The acrylic construction block of  claim 1  in which there are four side edges and each of the faces is square.  
     
     
         6 . The acrylic construction block of  claim 1  in which the infrared absorber additionally comprises carbon black.