Hermetically Sealable, Easy-Opeanable, Flexible Container of Heat-Shrinklable Thermoplastic Material

Abstract

A plastic bag for the manufacture of an easy-openable, hermetically sealed package, comprises a multi-layer heat-shrinkable film folded and/or heat-sealed to itself to form a flexible container with two closed side edges, a closed bottom side edge and an open top side, wherein said multi-layer heat-shrinkable film comprises a first outer heat-sealing layer (a), a second outer layer (b) and directly adhered to the heat-sealing layer (a) an internal layer (c) of a blend of at least two resin components that are only partially compatible so that said layer (c) will fail when a transversal force of from about 4 to about 9.5 N/25.4 mm is applied thereto. Preferably the bag is an ES bag and comprises an unsealed area extending beyond the factory bottom seal where the front and rear panels of the bag are separately graspable and usable as tabs to be pulled apart to initiate opening of the package. Also claimed is the packaged product comprising said plastic bag.

1 : A plastic bag for the manufacture of an easy-openable, hermetically sealed package, said plastic bag comprising a multi-layer heat-shrinkable film folded and/or heat-sealed to itself to form a flexible container with two closed side edges, a closed bottom side edge and an open top side, wherein said multi-layer heat-shrinkable film comprises a first outer heat-sealing layer (a), a second outer layer (b) and directly adhered to the heat-sealing layer (a) an internal layer (c) of a blend of at least two resin components that are only partially compatible so that said layer (c) will fail when a transversal force of from about 4 to about 9.5 N/25.4 mm is applied thereto. 
   
   
       2 : The plastic bag of  claim 1  which comprises an unsealed area extending beyond one of the seals forming the bag, where the front and rear panels of the bag itself are separately graspable and usable as tabs to be pulled apart to initiate opening of the package. 
   
   
       3 : The plastic bag of  claim 2  wherein said unsealed area beyond one of the seals forming the bag is present only along a small portion of the seal length. 
   
   
       4 : The plastic bag of  claim 2  wherein the seal beyond which the unsealed area extends, has a width less than about 4 mm. 
   
   
       5 : The plastic bag of  claim 1  which is an end seal bag. 
   
   
       6 : A packaged product comprising i) an easy-openable, hermetically sealed, plastic bag comprising a multi-layer heat-shrinkable film folded and/or heat-sealed to itself to form a closed flexible container, wherein said multi-layer heat-shrinkable film comprises at least a first outer heat-sealable layer (a), a second outer layer (b) and directly adhered to the heat-sealing layer (a) an internal layer (c) of a blend of at least two resin components that are only partially compatible so that said layer (c) will fail when a transversal force of from about 4 to about 9.5 N/25.4 mm is applied thereto, and ii) a product packaged in said bag, said plastic bag having an unsealed area extending beyond one of the seals of the package where the front and rear panels of the bag are separately graspable and usable as opening tabs. 
   
   
       7 : The packaged product of  claim 6  wherein the seal in the plastic bag beyond which the unsealed area extends has a width less than about 4 mm. 
   
   
       8 : The package of  claim 6  wherein the plastic bag is an end seal bag. 
   
   
       9 : The package of  claim 8  wherein the seal beyond which the unsealed area extends is the factory bottom seal. 
   
   
       10 : The package of  claim 9  wherein said unsealed area is present only along a small portion of the bottom seal length. 
   
   
       11 : The package of  claim 6  wherein the product is packaged under vacuum and the plastic bag is heat-shrunk around the product. 
   
   
       12 : The plastic bag of  claim 1  wherein the blend of resins for internal layer (c) comprises from about 35 wt. % to about 80 wt. % of a copolymer of ethylene and acrylic or methacrylic acid and in particular an ionomer, from about 15 wt. % to about 30 wt. % of a modified ethylene-vinyl acetate, and from about 2 wt. % to about 50 wt. % of a polybutene and preferably comprises from about 40 wt. % to about 70 wt. % of an ionomer, from about 15 wt. % to about 30 wt. % of a modified ethylene-vinyl acetate, and from about 10 wt. % to about 30 wt. % of a polybutene. 
   
   
       13 : The plastic bag of  claim 6 , wherein the blend of resins for internal layer (c) comprises from about 35 wt. % to about 80 wt. % of a copolymer of ethylene and acrylic or methacrylic acid and in particular an ionomer, from about 15 wt. % to about 30 wt. % of a modified ethylene-vinyl acetate, and from about 2 wt. % to about 50 wt. % of a polybutene and preferably comprises from about 40 wt. % to about 70 wt. % of an ionomer, from about 15 wt. % to about 30 wt. % of a modified ethylene-vinyl acetate, and from about 10 wt. % to about 30 wt. % of a polybutene.