Energy saving roof

Abstract

A roof has an outer surface with a first color under a first environmental condition and a second color under a second environmental condition. The outer surface is capable of both changing from the first color to the second color and from the second color to the first color.

1 . A roof comprising an outer surface, the outer surface having a first color under a first environmental condition and a second color under a second environmental condition, the outer surface capable of both changing from the first color to the second color and from the second color to the first color. 
     
     
         2 . The roof of  claim 1  wherein the first environmental condition is selected from the group consisting of temperature, light level, and any combination thereof. 
     
     
         3 . The roof of  claim 2  wherein the second environmental condition is selected from the group consisting of temperature, light level, and any combination thereof. 
     
     
         4 . The roof of  claim 1  wherein the outer surface comprises a thermochromatic coating. 
     
     
         5 . The roof of  claim 1  wherein the outer layer is a laminate comprising thermochromatic material. 
     
     
         6 . The roof of  claim 1  wherein the first color is substantially darker than the second color, the first color extant in cooler temperatures of between about −120 and 65 degrees Fahrenheit, the second color extant in warmer temperatures of between about 
     
     
         7 . The roof of  claim 1  having a transition from the first color to the second color that occurs at a threshold temperature. 
     
     
         8 . The roof of  claim 1  having a gradual transition from the first color to the second color with a rise in temperature. 
     
     
         9 . The roof of  claim 1  wherein the outer surface comprises (a) one or more electron-donating, chromatic organic compounds selected from the group consisting of diaryl phthalides, aryl phthalides, indolylphthalides, polyarylcarbinols, leucoauramines, acrylauramines, arylauramines, rhodamine B lactams, indolines, spiropyrans, fluorans, thiofluorans, phenothiazines, triphenylmethanes, diarylarylfurans, spiroxanthenearylfurans, and chromenoindoles, (b) one or more compounds capable of reversibly accepting electrons of said organic compound selected from the group consisting of phenolic hydroxy group-containing compounds and derivatives thereof and carboxyl group-containing compounds and derivatives thereof, (c) one or more compounds controlling the temperature and sensitivity of coloration/decoloration of said thermochromatic material selected from the group consisting of alcohols, esters, ketones, esters, acid amides and carboxylic acids, the ratio of each component to others (a):(b):(c) being 1:0.1 to 10:1 to 100 by weight, and (d) one or more radical cationic compounds selected from the group consisting of N-radical cationic, P-radical cationic, O-radical cationic and S-radical cationic compounds having aromatic ring(s), in an amount of from 0.01 to 5 parts by weight per 1 part by weight of said electron-donating chromatic organic compound, said radical cationic compound interacting with said electron-donating, chromatic organic compound to stabilize said compound, resulting in a thermochromatic material with an improved resistance to light. 
     
     
         10 . The roof of  claim 9  wherein the outer surface is a coating. 
     
     
         11 . The roof of  claim 10  wherein the coating is a powder coating selected from the material group consisting of epoxies, polyesters, urethanes, nylon, vinyl, polyethylene, and any combination thereof. 
     
     
         12 . The roof of  claim 10  wherein the coating is a paint (either sprayed or brushed). 
     
     
         13 . The roof of  claim 1  having roof panels, the outer surface disposed directly on the roof panels. 
     
     
         14 . The roof of  claim 1  having roof panels, the outer surface disposed on a membrane disposed on the roof panels. 
     
     
         15 . The roof of  claim 4  wherein the coating is a powder coating selected from the material group consisting of epoxies, polyesters, urethanes, nylon, vinyl, polyethylene, and any combination thereof. 
     
     
         16 . The roof of  claim 4  wherein the coating is a paint. 
     
     
         17 . The roof of  claim 1  wherein the outer coating is of uniform construction (define). 
     
     
         18 . The roof of  claim 1  wherein at least one portion of the roof maintains the substantially same color under the first environmental condition and the second environmental condition. 
     
     
         19 . A surface of a building comprising an outer surface, the outer surface having a first color under a first environmental condition and a second color under a second environmental condition, the outer surface capable of both changing from the first color to the second color and from the second color to the first color. 
     
     
         20 . The surface of  claim 19  selected from the group consisting of decks, porches, walls, patios, driveways, parking pads, parking lots, interior floors, and walkways.