Composite protective sheet material

Abstract

A composite protective sheet material for covering a smooth surface of a transparent material, especially but not exclusively for covering the surface of a lens. It comprises a film substrate at least one main surface of which is covered by an adhesive coating. At least a part of the said at least one main surface of the substrate is free or substantially free of adhesive, or has less adhesive applied to it than does the rest of that surface, thereby to provide a finger lift region of the film at an edge of the surface covered thereby.

1 . A composite protective sheet material for covering a smooth surface of a transparent material, especially but not exclusively for covering the surface of a lens, comprising a film substrate and an adhesive coating which covers at least one main surface of the film substrate, wherein at least a part of the said at least one main surface of the substrate is free or substantially free of adhesive, or has less adhesive applied to it than does the rest of that surface, thereby to provide a finger lift region of the film at an edge of the surface covered thereby. 
     
     
         2 . A sheet material according to  claim 1 , wherein the sheet material is elongate. 
     
     
         3 . A sheet material according to  claim 2 , wherein the sheet material is in the form of tape. 
     
     
         4 . A sheet material according to  claim 3 , wherein the sheet material is in the form of a roll of tape. 
     
     
         5 . A sheet material according to  claim 4 , wherein the sheet material is wound onto a reel. 
     
     
         6 . A sheet material according to  claim 1 , wherein the said part is an elongate strip. 
     
     
         7 . A sheet material according to  claim 2 , wherein the strip runs along the length of the sheet material. 
     
     
         8 . A sheet material according to  claim 4 , wherein the said part extends all the way along the tape. 
     
     
         9 . A sheet material according to  claim 1 , wherein the adhesive is visually distinct from the film substrate, to render the position of the finger lift region more evident. 
     
     
         10 . A sheet material according to  claim 9 , wherein the adhesive is coloured with a dye. 
     
     
         11 . A sheet material according to  claim 1 , wherein the film substrate is translucent. 
     
     
         12 . A sheet material according to  claim 11 , wherein the film substrate is transparent. 
     
     
         13 . A lens having a surface covered by a composite protective sheet material as claimed in  claim 1 . 
     
     
         14 . A method of making a sheet material according to  claim 1 , wherein a strip of material is secured around a roller which is used to even the spread of adhesive over the film substrate.