Removable Adhesive Label Containing Polymeric Film Layer Having Water Affinity

Abstract

An adhesive label includes a polymeric first film layer that has an affinity for water. The label is useful in various labeling applications and especially adhesive labeling of reusable and recyclable containers which require removal of the label during a washing process in a warm or hot washing fluid.

1 . A label, comprising:
 (a) a film having a first surface and a second surface and comprising a first film layer; and   (b) an adhesive layer having a first surface and a second surface and comprising an adhesive wherein the first surface of the adhesive layer is adhesively joined to the second surface of the film;   (c) wherein the first film layer comprises at least one thermoplastic polymer wherein the thermoplastic polymer has a glass transition temperature in the range of 35 to 105° C., and a tensile modulus of the film in the machine direction, which after heating, is less than the tensile modulus of the film in the machine direction in ambient air.   
     
     
         2 . The label of  claim 1  wherein the tensile modulus of the film after heating in water at a temperature of about 80° C. for at least about 3 minutes is less than about 40% of the tensile modulus of the film in the machine direction in ambient air. 
     
     
         3 . The label of  claim 1  wherein the first film layer has a tensile modulus (ASTM D882) in the machine direction of less than 945 MPa after immersion in water at a temperature of about 80° C. for at least about 3 minutes. 
     
     
         4 . The label of  claim 1  wherein the thermoplastic polymer of the first film layer comprises a polymer selected from the group consisting of an olefin-vinyl alcohol copolymer, an aromatic polyamide, and a mixture of two or more of any of the foregoing polymers. 
     
     
         5 . The label of  claim 1  wherein the thermoplastic polymer of the first film layer comprises a polymer selected from the group consisting of an ethylene-vinyl alcohol copolymer, an aromatic polyamide derived from an aliphatic dicarboxylic acid or acid halide and an aromatic diamine, and a mixture of two or more of any of the foregoing polymers. 
     
     
         6 . The label of  claim 1  wherein first film layer is nonoriented. 
     
     
         7 . The label of  claim 1  wherein the first film layer is oriented by stretching the first film layer uniaxially or biaxially and then annealing the uniaxially or biaxially stretched first film layer. 
     
     
         8 . The label of  claim 1  wherein the film is a monolayered film. 
     
     
         9 . The label of  claim 1  wherein the film is a multilayered film. 
     
     
         10 . The label of  claim 1  wherein the first film layer comprises two or more layers wherein each of the two or more layers comprises at least one thermoplastic polymer wherein the thermoplastic polymer has a glass transition temperature in the range of 35 to 105° C., and a tensile modulus of the film in the machine direction, which after heating, is less than the tensile modulus of the film in the machine direction in ambient air. 
     
     
         11 . The label of  claim 1  wherein the film comprises a second film layer wherein the second film layer comprises one layer or two or more layers wherein the one layer or each of the two or more layers comprises at least one thermoplastic polymer and the one layer or each of the two or more layers has a property selected from the group of at least one of: a) a tensile modulus (ASTM D882) in a machine direction of at least 945 MPa after immersion in water at a temperature of about 80° C. for at least about 3 minutes; b) an absolute areal dimensional change (ASTM D1204) of less than about 4% after immersion in water at a temperature of about 80° C. for at least about 3 minutes; or c) a water absorption (ASTM D570) of less than about 1.7% by weight after immersion in water at a temperature of about 80° C. for at least about 2 hours, or a combination of the foregoing properties. 
     
     
         12 . The label of  claim 11  wherein the second film layer has a first surface and a second surface, the first film layer has a first surface and a second surface, and the first surface of the first film layer underlies the second surface of the second film layer, and the first surface of the adhesive layer underlies the second surface of the first film layer. 
     
     
         13 . The label of  claim 11  wherein the first film layer has a first surface and a second surface, the second film layer has a first surface and a second surface, and the first surface of the second film layer underlies the second surface of the first film layer, and the first surface of the adhesive layer underlies the second surface of the second film layer. 
     
     
         14 . The label of  claim 1  wherein the adhesive of the adhesive layer is a pressure sensitive adhesive. 
     
     
         15 . The label of  claim 1  wherein the label further comprises a release liner having a first surface and a second surface wherein the first surface of the release liner is releasably attached to the second surface of the adhesive layer. 
     
     
         16 . The label of  claim 1  wherein the film is clear. 
     
     
         17 . A labeled container, comprising:
 the label of  claim 1 ; and   a container having a horizontal axis, wherein the label is attached to the container, wherein the second surface of the adhesive layer is adhesively joined to an outer surface of the container, and the machine direction or the transverse direction of the first film layer circumferentially follows the horizontal axis of the container.   
     
     
         18 . The labeled container of  claim 17  wherein the container is a cylindrically shaped container wherein the horizontal axis of the container is parallel to the circumference of the cylindrically shaped container. 
     
     
         19 . A method of removing a label from a container comprising:
 (i) providing a labeled container of  claim 17 ; and   (ii) removing the label from the container by immersing the container with the attached label in a liquid wherein the temperature of the liquid is at least about 50° C. and the label detaches from the container.   
     
     
         20 . The method of  claim 19  wherein the liquid is water or a caustic aqueous solution.