Pressure sensitive adhesive for photoactive or photographic substrates

Abstract

A method is provided for photographic developing using a roll of photographic paper. A photographic image is formed on the paper, and the image-containing portion of the paper cut from the roll of paper. The improvement comprises the end of the roll of paper being initially maintained in place by means of a pressure sensitive adhesive tape comprised of a polyisobutylene-or polybutene-based pressure sensitive adhesive on a backing layer, with the tape being removed prior to the roll being used as a substrate for the photographic image. The combination of a roll of photographic paper whose free end is held in place by the pressure sensitive adhesive is also provided.

1 . In a method for photographic developing using a roll of photographic paper, wherein a photographic image is formed on said paper, and said image-containing portion of said paper being cut from said roll of paper, the improvement wherein the end of said roll of paper is initially maintained in place by means of a pressure sensitive adhesive tape comprised of polyisobutylenes, polybutenes, or mixtures thereof on a backing layer, with said tape being removed prior to said roll being used as a substrate for said photographic image.  
   
   
       2 . The method of  claim 1 , wherein said pressure sensitive adhesive tape comprises a polyester backing layer.  
   
   
       3 . The method of  claim 1 , wherein a binder coating is applied between said backing layer and said pressure sensitive adhesive.  
   
   
       4 . The method of  claim 3 , wherein said binder coating has antistatic properties.  
   
   
       5 . The method of  claim 1 , wherein said adhesive is comprised of a mixture of high and low molecular weight polyisobutylene components present in ratios sufficient to result in a pressure sensitive adhesive.  
   
   
       6 . The method of  claim 1 , wherein said adhesive is comprised of a mixture of high and low molecular weight polybutene components present in ratios sufficient to result in a pressure sensitive adhesive.  
   
   
       7 . The method of  claim 5 , wherein the high molecular weight fraction may be characterized by a molecular weight M w  in the range of 1,000,000 to 1,800,000, and a molecular weight M n  in the range of from 500,000 to 900,000, and the low molecular weight fraction may be characterized by a molecular weight M w  of up to about 27,000 and a molecular weight M n  of up to about 10,000.  
   
   
       8 . The method of  claim 6 , wherein the high molecular weight fraction may be characterized by a molecular weight M w  in the range of 1,000,000 to 1,800,000, and a molecular weight M n  in the range of from 500,000 to 900,000, and the low molecular weight fraction may be characterized by a molecular weight M w  of up to about 27,000 and a molecular weight M n  of up to about 10,000.  
   
   
       9 . The method of  claim 5 , wherein the weight ratio of low molecular weight fraction to high molecular weight fraction ranges from about 20:80 to 60:40.  
   
   
       10 . The method of  claim 6 , wherein the weight ratio of low molecular weight fraction to high molecular weight fraction ranges from about 20:80 to 60:40.  
   
   
       11 . The method of  claim 1 , wherein said pressure sensitive adhesive is free of free monomers, acrylic acids or silicone polymer components.  
   
   
       12 . The method of  claim 1 , wherein said pressure sensitive adhesive comprises a mixture of polyisobutylenes and polybutenes.  
   
   
       13 . In combination with a roll of photographic paper, a pressure sensitive adhesive tape maintaining a free end of said paper roll in place against said roll of paper, the improvement wherein said adhesive tape is comprised of a pressure sensitive adhesive comprised of polyisobutyenes, polybutenes, or mixtures thereof on a backing layer.  
   
   
       14 . The combination of  claim 13 , wherein said polyisobutylene adhesive is comprised of a mixture of high and low molecular weight polyisobutylene in a ratio sufficient to result in pressure sensitive adhesive properties.  
   
   
       15 . The combination of  claim 13 , wherein said polybutene adhesive is comprised of a mixture of high and low molecular weight polybutene in a ratio sufficient to result in pressure sensitive adhesive properties.  
   
   
       16 . The combination of  claim 14 , wherein the high molecular weight fraction may be characterized by a molecular weight M w  in the range of 1,000,000 to 1,800,000, and a molecular weight M n  in the range of from 500,000 to 900,000, and the low molecular weight fraction may be characterized by a molecular weight M w  of up to about 27,000 and a molecular weight M n  of up to about 10,000.  
   
   
       17 . The combination of  claim 15 , wherein the high molecular weight fraction may be characterized by a molecular weight M w  in the range of 1,000,000 to 1,800,000, and a molecular weight M w  in the range of from 500,000 to 900,000, and the low molecular weight fraction may be characterized by a molecular weight M w  of up to about 27,000 and a molecular weight M n  of up to about 10,000.  
   
   
       18 . The combination of  claim 14 , wherein the weight ratio of low molecular weight fraction to high molecular weight fraction ranges from about 20:80 to 60:40.  
   
   
       19 . The combination of  claim 15 , wherein the weight ratio of low molecular weight fraction to high molecular weight fraction ranges from about 20:80 to 60:40.  
   
   
       20 . The combination of  claim 13 , wherein said pressure sensitive adhesive is free of free monomers, acrylic acids or silicone polymers.  
   
   
       21 . The combination of  claim 13 , wherein a binder coating is present between said backing layer and said pressure sensitive adhesive.  
   
   
       22 . The combination of  claim 21 , wherein said binder coating has antistatic properties.  
   
   
       23 . The combination of  claim 13 , wherein said backing layer is a polyester layer.