Label assemblies for adverse environments

Abstract

Various labels for use in adverse environments are described. The labels are particularly well suited for applications in which a permanent label bond is required. The labels utilize a two stage adhesive which is initially in the form of a pressure sensitive adhesive (PSA) and then upon heating, converted to a permanent non-PSA.

What is claimed is: 
     
         1 . A method of labeling an article, the method comprising:
 providing an article having an outer surface;   providing a label assembly comprising (i) a first face layer defining a first face and an oppositely directed second face, and (ii) a two stage adhesive disposed on at least one of the first face and the second face of the first face layer, the two stage adhesive exhibiting a first stage in which the adhesive is initially in the form of a pressure sensitive adhesive (PSA) and upon exposure to heat, converts from the PSA to a permanent, non-PSA,   wherein the pressure sensitive adhesive comprises 10-90 wt % of an acrylic backbone base polymer having a molecular weight (Mw) of 5,000 to 1,000,000;   adhering the adhesive of the label assembly to the outer surface of the article.   
     
     
         2 . The method of  claim 1  wherein the glass transition temperature (Tg) of the acrylic backbone base polymer is less than 50° C. 
     
     
         3 . The method of  claim 1  wherein the glass transition temperature (Tg) of the acrylic backbone base polymer is less than 0° C. 
     
     
         4 . The method of  claim 1  wherein the pressure sensitive adhesive comprises
 20-80 wt % of the acrylic backbone base polymer having a molecular weight (Mw) of 5,000 to 1,000,000; 
 5-80 wt % of at least one structural diluent; 
 0-4 wt % of at least one crosslinker; 
 0-10 wt % of a catalyst; and 
 0-10 wt % of stabilizer/process aid. 
 
     
     
         5 . The method of  claim 1  wherein the thickness of the first face layer is from about 20 microns to about 150 microns. 
     
     
         6 . The method of  claim 1  wherein the adhering is performed by contacting the adhesive of the label assembly to the outer surface of the article. 
     
     
         7 . The method of  claim 1  wherein the adhering is performed by contacting the adhesive of the label assembly to the outer surface of the article followed by converting the adhesive to the second stage. 
     
     
         8 . The method of  claim 7  wherein the converting is performed by heating the adhesive to a temperature within a range of from 80° C. to 240° C. 
     
     
         9 . The method of  claim 8  wherein heating is performed in combination with contacting the adhesive of the label assembly to the outer surface of the article. 
     
     
         10 . The method of  claim 9  wherein the contacting is performed for a time period within a range of from about 1 second to about 200 seconds. 
     
     
         11 . The method of  claim 10  wherein the heating and contacting are simultaneously applied to the label assembly for a time period of from about 0.5 seconds to about 10 seconds, the contacting is performed by applying a pressure. 
     
     
         12 . The method of  claim 11  wherein the pressure is from 1 psi to about 100 psi. 
     
     
         13 . The method of  claim 1  wherein the label assembly further comprises a primer layer disposed between the first face layer and the two stage adhesive. 
     
     
         14 . The method of  claim 1  wherein the label assembly further comprises a liner disposed on the two stage adhesive. 
     
     
         15 . The method of  claim 1  wherein the two stage adhesive is disposed on the second face of the first face layer, the label assembly further comprises a topcoat disposed on the first face of the first face layer. 
     
     
         16 . The method of  claim 1  wherein the first face layer is selected from the group consisting of poly(vinyl chloride) (PVC), poly(ethylene terephthalate) (PET), polyolefins, polyamides, synthetic textiles, synthetic leathers, paper, fiber glass, polyvinylidene fluoride (PVF), metal foils, ceramics, natural leather, and combinations thereof. 
     
     
         17 . The method of  claim 1  wherein the first face layer is selected from the group consisting of poly(vinyl chloride) (PVC) film, poly(ethylene terephthalate) (PET) film, polyolefin film, polyamide film, synthetic textiles, synthetic leathers, paper, fiber glass, polyvinylidene fluoride (PVF) film, metal foils, ceramics, natural leather, and combinations thereof. 
     
     
         18 . The method of  claim 1  wherein the label assembly further comprises (iii) a second face layer, and (iv) a component disposed between the first face layer and the second face layer. 
     
     
         19 . The method of  claim 18  wherein the component is an electronic component. 
     
     
         20 . The method of  claim 18  wherein the component is wherein the component is a RFID. 
     
     
         21 . The method of  claim 18  wherein the label assembly further comprises (v) a two stage adhesive disposed on at least one of the first face and the second face of the second face layer, the two stage adhesive exhibiting a first stage in which the adhesive is initially in the form of a pressure sensitive adhesive (PSA) and upon exposure to heat, converts from the PSA to a permanent, non-PSA.