Adhesive for bag sealing application

Abstract

Packaging bags having preapplied thereon a reactivatable adhesive.

1 . A packaging bag having preapplied to at least a portion thereof a reactivatable adhesive, wherein the reactivatable adhesive comprises an effective amount of an energy-absorbing ingredient such that upon exposure of the adhesive to radiant energy having a wavelength of from about 400 nm to about 100,000 nm the adhesive is activated, said process comprising exposing the applied adhesive with radiant energy having a wavelength of from about 400 nm to about 100,000 nm for a time sufficient to melt the adhesive, bringing one of said substrates in contact with the melted adhesive on the other substrate, and allowing the adhesive to solidify thereby bonding the first substrate to the second substrate.  
     
     
         2 . The bag of  claim 1  wherein the adhesive is activated upon exposure to radiant energy having a wavelength of from about 700 nm to about 5000 nm.  
     
     
         3 . The bag of  claim 1  wherein the preapplied adhesive is exposed to said radiant energy for a period of time of less than about 5 seconds.  
     
     
         4 . The bag of  claim 1  wherein the preapplied adhesive is exposed to said radiant energy for a period of time of less than about 2 seconds.  
     
     
         5 . The bag of  claim 1  comprising at least one closable bag ending, said adhesive being present on said bag ending.  
     
     
         6 . The bag of  claim 5  wherein the bag is made of coated paper.  
     
     
         7 . The bag of  claim 5  comprising a plastic liner bag.  
     
     
         8 . The bag of  claim 1  wherein the adhesive preapplied to said bag comprises an organic dye.  
     
     
         9 . The bag of  claim 1  wherein the adhesive preapplied to said bag comprises a pigment.  
     
     
         10 . The bag of  claim 9  wherein the adhesive comprises carbon black.  
     
     
         11 . The bag of  claim 1  wherein the reactivatable adhesive is a thermoplastic adhesive.  
     
     
         12 . The bag of  claim 1  wherein the reactivatable adhesive is a hot melt adhesive.  
     
     
         13 . A process of packaging an article by forming, filling and sealing a packaging bag that has had applied to at least a portion thereof a reactivatable adhesive, wherein said process comprising forming and/or sealing a packaging bag by exposing the applied reactivatable adhesive to radiant energy for a time sufficient to reactivate the adhesive, said radiant energy having a peak wavelength of from about 400 nm to about 100,000 nm.  
     
     
         14 . The process of  claim 1  wherein the adhesive is activated upon exposure to radiant energy having a wavelength of from about 700 nm to about 5000 nm.  
     
     
         15 . The process bag of  claim 1  wherein the preapplied adhesive is exposed to said radiant energy for a period of time of less than about 2 seconds.  
     
     
         16 . The process of  claim 13  wherein the adhesive preapplied to said bag comprises an organic dye.  
     
     
         17 . The process of  claim 13  wherein the adhesive preapplied to said bag comprises a pigment.  
     
     
         18 . The process of  claim 17  wherein the comprises carbon black.  
     
     
         19 . The bag of  claim 13  wherein the reactivatable adhesive is a thermoplastic adhesive.  
     
     
         20 . The bag of  claim 13  wherein the reactivatable adhesive is a hot melt adhesive.