Opaque Adhesives in Wet Condition for Label Application

Abstract

Various opacifying adhesive compositions are described. The adhesives exhibit relatively high levels of opacity in wet conditions while maintaining acceptable adhesive properties. Also described are label assemblies and labeled containers using such adhesives. Related methods of use and preparation are also described.

What is claimed is: 
     
         1 . A label adapted to remain opaque in wet condition for pressure sensitive application, said label comprising:
 an outer layer of facestock for receiving printed indicia;   a first opacifying adhesive layer and a second opacifying adhesive layer,   wherein said first opacifying adhesive layer underlies said facestock,   wherein said second opacifying adhesive layer underlies said first opacifying adhesive layer,
 wherein said first opacifying adhesive layer includes a first adhesive component and a first pigment component in a proportion sufficient to maintain opacity when exposed to an aqueous environment and a peel adhesion of at least 1 N/inch and a loop tack of at least 2 N/inch of said first opacifying adhesive layer in said pressure sensitive application, 
 wherein said second opacifying adhesive layer includes a second adhesive component and a second pigment component in a proportion sufficient to maintain opacity when exposed to an aqueous environment and a peel adhesion of at least 1 N/inch and a loop tack of at least 2 N/inch of said second opacifying adhesive layer in said pressure sensitive application; and 
   a liner underlying said second opacifying adhesive layer.   
     
     
         2 . The label of  claim 1 , wherein said first adhesive component and said second adhesive component are each independently selected from the group consisting of emulsion adhesives, hot-melt adhesives, solvent adhesives, and combinations thereof. 
     
     
         3 . The label of  claim 1 , wherein said first pigment and said second pigment each has an acceptable wet opacity. 
     
     
         4 . The label of  claim 1 , wherein said first pigment and said second pigment comprises TiO 2 . 
     
     
         5 . The label of  claim 1 , wherein said first pigment component is present in a weight range of about 10% to about 50% of said first adhesive component. 
     
     
         6 . The label of  claim 1 , wherein said second pigment component in present in a weight range of about 1% to about 10% of said second adhesive component. 
     
     
         7 . The label of  claim 1 , wherein said opacity in wet condition is about 80% to 90%. 
     
     
         8 . The label of  claim 1 , wherein said first opacifying adhesive layer has coat weight of about 13 grams per square meter (gsm) to about 25 grams per square meter (gsm). 
     
     
         9 . The label of  claim 1 , wherein said second opacifying adhesive layer has coat weight of about 6 grams per square meter (gsm) to about 20 grams per square meter (gsm). 
     
     
         10 . The label of  claim 1 , wherein said pressure sensitive application is performed on a substrate that comprises glass. 
     
     
         11 . The label of  claim 1 , wherein said pressure sensitive application is performed on a substrate that comprises high density polyethylene (HDPE). 
     
     
         12 . The label of  claim 1 , wherein said facestock is a paper facestock. 
     
     
         13 . The label of  claim 1 , wherein said facestock is plastic facestock. 
     
     
         14 . The label of  claim 1 , wherein said loop tack is at least 3 newtons per inch (N/inch) when said facestock is paper and when said pressure sensitive application is performed on a high density polyethylene (HDPE) substrate. 
     
     
         15 . The label of  claim 1  further comprising:
 a clear or transparent layer. 
 
     
     
         16 . The label of  claim 1  further comprising:
 a metallic layer. 
 
     
     
         17 . A method of preparation of an opacifying adhesive composition which is adapted to remain opaque in wet condition for pressure sensitive label application, said method comprising the steps of:
 mixing a proportionate amount of an adhesive component and pigment component with agitation; and   wherein said opacifying adhesive does not cause any unacceptable loss of peel adhesion or tack of the adhesive component in pressure sensitive application.