Diffusive Light Reflectors With Polymeric Coating And Opaque Blackout Layer

Abstract

A diffuse light reflector is disclosed for use in lighting fixtures including luminaires, light boxes, displays, signage, daylighting applications, and the like. The reflector includes a light reflective nonwoven, a polymer layer that enhances reflectivity, and an opaque blackout layer. The reflector can be laminated to coil steel or aluminum and can be formed in metal coil or sheet forming operations. The polymer layer can be easily cleaned of machine oils from the metal forming operations.

What is claimed is: 
     
         1 . A diffuse light reflector comprising a plexifilamentary film-fibril sheet substrate having a first side and a second side, wherein the first side is adapted to be adjacent to a light source, and a polymer layer on said first side of said film-fibril sheet, and an opaque blackout layer on said second side of said film-fibril sheet, wherein the polymer layer is a polyolefin, polyester, polyacrylate or blends thereof. 
     
     
         2 . The diffusive light reflector of  claim 2 , wherein said opaque blackout layer comprises carbon black. 
     
     
         3 . The diffusive light reflector of  claim 1  having a gloss of less than 10%. 
     
     
         4 . The diffusive light reflector of  claim 3  having a gloss of about 5%. 
     
     
         5 . The diffusive light reflector of  claim 1  having a reflectance from about 94% to about 97% measured at 550 nm. 
     
     
         6 . The diffusive light reflector of  claim 1  having an average surface roughness on said first side from about 6.4 microns to about 2.8 microns, measured at 5× magnification. 
     
     
         7 . The diffusive light reflector of  claim 6 , wherein the average surface roughness is about 3.5 microns, measured at 5× magnification. 
     
     
         8 . The diffusive light reflector of  claim 1 , having a roughness uniformity on said first side of less than about 1.0 microns, measured at 5× magnification. 
     
     
         9 . The diffusive light reflector of  claim 8 , wherein the roughness uniformity is about 0.4 microns, measured at 5× magnification. 
     
     
         10 . The reflector of  claim 1 , wherein said polymer layer comprises high density polyethylene or low density polyethylene 
     
     
         11 . The reflector of  claim 1  having a thickness between about 150 microns and about 1000 microns 
     
     
         12 . The reflector  claim 1 , wherein said polymer layer is extruded on said first side of said film fibril sheet 
     
     
         13 . The reflector  claim 1 , wherein said polymer layer comprises a polyethylene methacrylate copolymer blend 
     
     
         14 . The reflector of  claim 1 , wherein said polymer layer comprises a blend of high density polyethylene and low density polyethylene 
     
     
         15 . The reflector of  claim 1 , wherein said polymer layer comprises at least one component selected from the group consisting of titanium dioxide and barium sulfate at an amount greater than about 3 to about 20 weight percent of said polymer layer. 
     
     
         16 . A laminate comprising the reflector of  claim 1  or  2  affixed to a steel or aluminum sheet. 
     
     
         17 . A lighting fixture comprising a laminate comprising the reflector of  claim 1  or  2  affixed to a steel or aluminum sheet, wherein said lighting fixture is selected from the group consisting of luminaries, lighted signs, and daylighting reflectors. 
     
     
         18 . A method of providing diffuse light to plants comprising: (a) providing a plexifilamentary film-fibril sheet substrate having a first side and a second side, wherein the first side is adapted to be adjacent to a light source, and a polymer layer on said first side of said film-fibril sheet, and an opaque blackout layer on said second side of said film-fibril sheet, wherein the polymer layer is a polyolefin, polyester, polyacrylate or blends thereof; and (b) directing diffuse light from said plexifilmentary film-fibril sheet onto said plants.