Repulpable silicone release liner paper with dissolvable layer

Abstract

A method of producing and repulping paper having a silicone release liner includes producing paper having a silicone release liner that is initially secured to the paper by a dissolvable material. During production of the paper, a water-soluble coating may be applied to a paper surface, and a silicone release coating is then applied to the water-soluble coating. Upon rewetting of the paper during repulping, the water-soluble coating dissolves, thereby enabling separation of the silicone release coating from the paper. The repulpable silicone release liner permits recovery of paper fibers using conventional repulping and recycling processes.

The invention claimed is: 
     
         1 . A method of making repulpable paper, the method comprising:
 coating at least a portion of a sheet of paper with a water-soluble material;   coating at least a portion of the water-soluble material with a silicone material to form a silicone release paper.   
     
     
         2 . The method of  claim 1 , including:
 providing label stock having adhesive on at least one side thereof; and   releasably adhering the label stock to the silicone release paper by bringing the adhesive into contact with the silicone material.   
     
     
         3 . The method of  claim 1 , wherein:
 the silicone material initially comprises a silicone polymer, a crosslinker, and a catalyst.   
     
     
         4 . The method of  claim 1 , wherein:
 the silicone material is selected from the group consisting of solvent-based silicone, water-based silicone, and solvent-less silicone.   
     
     
         5 . The method of  claim 1 , wherein:
 the water-soluble material comprises at least one of sodium alginate and partially hydrolyzed polyvinyl alcohol.   
     
     
         6 . The method of  claim 1 , wherein:
 the water-soluble material comprises a water soluble polymer.   
     
     
         7 . The method of  claim 6 , wherein:
 the water soluble polymer is selected from the group consisting of carboxymethylated cellulose, ethylated starch, and carboxylated soy protein.   
     
     
         8 . The method of  claim 1 , wherein:
 the water soluble material forms a coating having a coat weight of about 2.0-6.0 gsm.   
     
     
         9 . The method of  claim 1 , wherein:
 the silicone material forms a coating having a coat weight of about 2.0-100.0 gsm.   
     
     
         10 . The method of  claim 1 , including:
 repulping the paper after coating the paper with water-soluble material and silicone material.   
     
     
         11 . The method of  claim 10 , wherein:
 repulping the paper includes bringing the water-soluble material into contact with water.   
     
     
         12 . The method of  claim 11 , wherein:
 the paper is soaked in water for at least about 30 minutes.   
     
     
         13 . The method of  claim 12 , wherein:
 the paper is soaked in water for at least about 60 minutes.   
     
     
         14 . The method of  claim 10 , wherein:
 a hydrapulper machine is utilized to repulp the paper.   
     
     
         15 . The method of  claim 14 , including:
 soaking the paper in water prior to placing the paper into a hydrapulper machine.   
     
     
         16 . The method of  claim 10 , wherein:
 repulping the paper results in less than 15 percent rejects according to predefined criteria.   
     
     
         17 . The method of  claim 15 , including:
 skimming off material floating on the surface after soaking the paper.   
     
     
         18 . A method of making repulpable paper, the method comprising:
 coating at least a portion of a sheet of paper with a layer of dissolvable sacrificial material; and   coating at least a portion of the dissolvable sacrificial material with a release material having non-stick properties.   
     
     
         19 . The method of  claim 18 , wherein:
 the dissolvable sacrificial layer dissolves in water.   
     
     
         20 . The method of  claim 18 , wherein:
 the release material comprises silicone.