Constructions for moisture sensitive thermochromic layers and structures having reduced moisture content in thermochromic layers

Abstract

A stack or roll of alternating layers of films or sheets. The stack or roll includes an interlayer film or sheet with a thermochromic PVB of a polymer, at least one transition metal ion, at least one high epsilon ligand capable of forming a high epsilon metal-ligand complex with the transition metal ion and at least one low epsilon ligand capable of forming an low epsilon metal-ligand complex with the transition metal ion. A desiccant-containing film or sheet is juxtaposed or interleaved with the interlayer film or sheet. The desiccant-containing film or sheet prevents blocking of the interlayer film or sheet and is capable of removing moisture from the interlayer film or sheet. The desiccant-containing film or sheet is releasably attached to the interlayer film or sheet.

What is claimed is: 
     
         1 . A stack or roll of alternating layers of films or sheets comprising:
 an interlayer film or sheet comprising a thermochromic PVB, wherein the thermochromic PVB comprises a polymer, at least one transition metal ion, at least one high epsilon ligand capable of forming a high epsilon metal-ligand complex with the transition metal ion and at least one low epsilon ligand capable of forming an low epsilon metal-ligand complex with the transition metal ion; and   a desiccant-containing film or sheet juxtaposed or interleaved with the interlayer film or sheet;   wherein the desiccant-containing film or sheet prevents blocking of the interlayer film or sheet;   wherein the desiccant-containing film or sheet is capable of removing moisture from the interlayer film or sheet; and   wherein the desiccant-containing film or sheet is releasably attached to the interlayer film or sheet.   
     
     
         2 . The stack or roll of  claim 1  wherein the desiccant-containing film or sheet interleaves the interlayer film or sheet. 
     
     
         3 . The stack or roll of  claim 1  wherein the desiccant-containing film or sheet has a textured surface or is bonded to a support that has a textured surface. 
     
     
         4 . The stack or roll of  claim 3  wherein the desiccant-containing film or sheet is embossed to provide the textured surface. 
     
     
         5 . The stack or roll of  claim 3  wherein the desiccant-containing film or sheet is bonded to one or more than one permeable support layer. 
     
     
         6 . The stack or roll of  claim 3  wherein the desiccant-containing film or sheet is bonded to one or more than one layer of mesh or fabric. 
     
     
         7 . The stack or roll of  claim 3  wherein the desiccant-containing film or sheet is bonded to one or more than one layer of nonwoven. 
     
     
         8 . The stack or roll of  claim 7  wherein the desiccant-containing film or sheet is bonded to one or more than one layer of polyethylene nonwoven. 
     
     
         9 . The stack or roll of  claim 1  wherein the stack or roll is packaged or wrapped in an external film that cooperates with the desiccant-containing film or sheet to provide a thermochromic PVB film or sheet exhibiting reduced moisture. 
     
     
         10 . The stack or roll of  claim 1  comprising the interlayer film and the desiccant-containing film wound into a roll. 
     
     
         11 . The stack or roll of  claim 10  wherein the desiccant-containing film resides on the outer surface of the roll. 
     
     
         12 . The stack or roll of  claim 1  wherein the desiccant-containing film or sheet comprises polyethylene and calcium oxide particles. 
     
     
         13 . The stack or roll of  claim 12  wherein the desiccant-containing film is a polyethylene film having calcium oxide particles dispersed therein which is overcoated on one or both sides with a moisture-permeable low density polyethylene. 
     
     
         14 . The stack or roll of  claim 1  wherein the interlayer film or sheet and the desiccant-containing film or sheet are both textured, wherein the texture of the desiccant-containing film or sheet helps preserve the texture of the interlayer film or sheet. 
     
     
         15 . The stack or roll of  claim 1  comprising a sealed bag with a foil lining therein, wherein the sealed bag contains the stack or roll of the interlayer film or sheet and the desiccant-containing film or sheet. 
     
     
         16 . The stack or roll of  claim 1  wherein the moisture content of the interlayer film or sheet is below about 0.4%. 
     
     
         17 . The stack or roll of  claim 1  wherein the wherein the desiccant-containing film or sheet has a thickness from 0.001 inches to 0.01 inches. 
     
     
         18 . A stack or roll of alternating layers of films or sheets comprising:
 an interlayer film or sheet comprising a thermochromic PVB, wherein the thermochromic PVB comprises a polymer, at least one transition metal ion, at least one high epsilon ligand capable of forming a high epsilon metal-ligand complex with the transition metal ion and at least one low epsilon ligand capable of forming an low epsilon metal-ligand complex with the transition metal ion; and   a desiccant-containing film or sheet juxtaposed or interleaved with the interlayer film or sheet;   wherein the desiccant-containing film or sheet has a textured surface or is bonded to a support that has a textured surface.   wherein the desiccant-containing film or sheet prevents blocking of the interlayer film or sheet;   wherein the desiccant-containing film or sheet is capable of removing moisture from the interlayer film or sheet; and   wherein the desiccant-containing film or sheet is releasably attached to the interlayer film or sheet.   
     
     
         19 . A stack or roll of alternating layers of films or sheets comprising:
 an interlayer film or sheet comprising a thermochromic PVB, wherein the thermochromic PVB comprises a polymer, at least one transition metal ion, at least one high epsilon ligand capable of forming a high epsilon metal-ligand complex with the transition metal ion and at least one low epsilon ligand capable of forming an low epsilon metal-ligand complex with the transition metal ion;   wherein the interlayer film or sheet has a textured surface; and   a desiccant-containing film or sheet juxtaposed or interleaved with the interlayer film or sheet;   wherein the desiccant-containing film or sheet has a textured surface or is bonded to a support that has a textured surface.   wherein the desiccant-containing film or sheet is capable of removing moisture from the interlayer film or sheet; and   wherein the textured surface of the desiccant-containing film or sheet or the support is releasably attached to the textured surface of the interlayer film or sheet.   
     
     
         20 . The stack or roll of  claim 19  wherein the desiccant-containing film or sheet prevents blocking of the interlayer film or sheet.