Back pad capable of color rendering end-of-life and manufacturing method thereof

Abstract

A back pad capable of color rendering end-of-life includes an absorption layer, a dye capsule layer and a carrier layer. The absorption layer has a surface. The dye capsule layer is disposed on the surface of the absorption layer. The carrier layer is laminated onto the dye capsule layer. The dye capsule layer of the present disclosure can be dissolved to release dyes after water penetrates in the back pad, and the end-of-life of the back pad can be easily determined through a color-rendering effect of the dyes.

What is claimed is: 
     
         1 . A back pad capable of color rendering end-of-life, comprising:
 an absorption layer having a surface;   a dye capsule layer disposed on the surface of the absorption layer; and   a carrier layer laminated onto the dye capsule layer.   
     
     
         2 . The back pad of  claim 1 , wherein the absorption layer is a polyurethane (PU) film. 
     
     
         3 . The back pad of  claim 1 , wherein the dye capsule layer includes at least io one dye micro-capsule. 
     
     
         4 . The back pad of  claim 3 , wherein a length of the dye micro-capsule is in a range of 10 μm to 100 μm inclusive. 
     
     
         5 . The back pad of  claim 3 , wherein the dye micro-capsule includes a soluble capsule body and a dye disposed in the soluble capsule body. 
     
     
         6 . The back pad of  claim 1 , wherein a thickness of the dye capsule layer is in a range of 10 μm to 1000 μm inclusive. 
     
     
         7 . The back pad of  claim 1 , wherein a thickness of the dye capsule layer is less than a thickness of the absorption layer. 
     
     
         8 . The back pad of  claim 1 , wherein a thickness of the dye capsule layer is less than a thickness of the carrier layer. 
     
     
         9 . The back pad of  claim 1 , wherein the carrier layer is a gum film. 
     
     
         10 . The back pad of  claim 1 , further comprising an adhesive layer disposed between the dye capsule layer and the carrier layer.