Easy open package

Abstract

An easy open package adapted to be heat sealed closed and peelably reopened including a first package wall comprising an outer layer, an inner sealant layer and a tie layer disposed between and peelably bonded to either the inner layer or the outer layer and a second package wall joined about a portion of its perimeter to the first package wall and comprising at least one layer, that layer being a sealant layer having the same composition as the inner sealant layer of the first package wall and disposed adjacent thereto, the sealant layers being heat sealable together to form a bond having a bond strength greater than the bond between the tie layer and the layer to which it is peelably bonded, that bond strength being predetermined by the selection of the compositions of the adjacent layers.

What is claimed is:  
     
       1. An easy open package adapted to be heat sealed to a closed condition to contain and protect product disposed therein, but which is readily openable by application of force, said package including a first package wall having a first thermoplastic polymeric film construction of a three layer coextrusion comprising a first outer layer, a first inner sealant layer of polymer and a first tie layer disposed between said first outer layer and said first inner sealant layer, said tie layer comprising a combination of polybutylene and one other constituent and being peelably bonded to one of either  only one of said first outer layer or  and said first inner sealant layer and said tie layer further being permanently bonded to the other layer to which said tie layer is not peelably bonded, a second package wall joined at a portion of its perimeter to said first package wall, said second package wall having a second thermoplastic polymeric film construction with a second inner sealant layer of the same polymer as, and disposed adjacent to, said first inner sealant layer of said first film construction, a second outer layer, and a second tie layer disposed between said second outer layer and said second inner sealant layer, said second tie layer being peelably bonded to one of either said second outer layer or said second inner sealant layer and permanently bonded to the other of said second outer layer or said second inner sealant layer, whereby when said first inner sealant layer of said first film construction is heat sealed to said adjacent second inner sealant layer of said second film construction along a heat seal, a bond is formed between said inner sealant layers having greater bond strength than the peelable bond between said tie layer and said one layer of said first film construction to which said tie layer is peelably bonded such that upon application of force to open said package, the first and second inner sealant layers will remain bonded together and opening will take place between the peelably bonded layers at said heat seal. 
     
     
       2. The easy open package of claim  1  wherein said first outer layer of said first package wall is selected from the group consisting of ethylene vinyl acetate copolymer, linear low density polyethylene, ethylene ethyl acrylate copolymer, ethylene methyl acrylate copolymer, neutralized ethylene acid copolymer, or  and low density polyethylene. 
     
     
       3. The easy open package of claim  1  wherein said first inner sealant layer of said first package wall is selected from the group consisting of ethylene acid copolymer, linear low density polyethylene, low density polyethylene or  and ethylene vinyl acetate copolymer. 
     
     
       4. The easy open package of claim  1  wherein said one other constituent of said tie layer is selected from the group consisting of ethylene vinyl acetate copolymer, ethylene acid copolymer and linear low density polyethylene. 
     
     
       5. The easy open package of claim  1  wherein said first tie layer is permanently bonded to said first outer layer and peelably bonded to said first inner sealant layer, said first tie layer consisting of said other constituent and between 5 and 30% polybutylene and wherein said first outer layer consists entirely of said other constituent. 
     
     
       6. The easy open package of claim  1  wherein said first tie layer is permanently bonded to said first outer layer and peelably bonded to said first inner sealant layer, said first tie layer consisting of said other constituent and between 5 and 30% polybutylene and wherein said first outer layer consists of at least 50% of said other constituent and a correlative percentage of a third  another constituent. 
     
     
       7. The easy open package of claim  1  wherein said first tie layer is permanently bonded to said first inner sealant layer and peelably bonded to said first outer layer, said first tie layer consisting of said other constituent and between 5 and 30% polybutylene and wherein said first inner sealant layer consists entirely of said other constituent. 
     
     
       8. The easy open package of claim  1  wherein said first tie layer is permanently bonded to said first inner sealant layer and peelably bonded to said first outer layer, said first tie layer consisting of said other constituent and between 5 and 30% polybutylene and wherein said first inner sealant layer consists of at least 50% of said other constituent and a correlative percentage of a third  another constituent. 
     
     
       9. The easy open package of claim  1  wherein said first outer layer is comprised of 50% ethylene vinyl aceetate copolymer and 50% linear low density polyethylene, said first inner sealant layer is comprised of substantially 100% neutralized ethylene acid copolymer and said first tie layer is comprised of 88% ethylene vinyl acetate copolymer and 12% polybutylene. 
     
     
       10. The easy open package of claim  1  wherein said first outer layer is comprised of substantially 100% ethylene vinyl acetate copolymer, said first inner sealant layer is comprised of substantially 100% neutralized ethylene acid copolymer and said first tie layer is comprised of 85% neutralized ethylene acid copolymer and 15% polybutylene. 
     
     
       11. The easy open package of claim  1  wherein said first outer layer is comprised of 50% ethylene vinyl acetate copolymer and 50% linear low density polyethylene, said first inner sealant layer is comprised of substantially 100% neutralized ethylene acid copolymer and said first tie layer is comprised of 85% neutralized ethylene acid copolymer and 15% polybutylene. 
     
     
       12. The easy open package of claim  1  wherein said first outer layer is comprised of substantially 100% linear low density of polyethylene, said first inner sealant layer is comprised of substantially 100% neutralized ethylene acid copolymer and said first tie layer is comprised of 88% linear low density polyethylene and 12% polybutylene. 
     
     
       13. The easy open package of claim  1  wherein said first outer layer is comprised of substantially 100% ethylene vinyl acetate copolymer, said first inner sealant layer is comprised of substantially 100% linear low density polyethylene and said first tie layer is comprised of 85% ethylene vinyl acetate copolymer and 15% polybutylene. 
     
     
       14. The easy open package of claim  1  wherein said second package wall includes a second outer layer adjacent to and disposed exteriorly of said second inner sealant layer. 
     
     
       15. The easy open package of claim  14  wherein said second package wall includes a second tie layer disposed between said second outer layer and said second inner sealant layer. 
     
     
       16. The easy open package of claim  15  wherein said second tie layer is peelably bonded to one of either said second outer layer or said second inner sealant layer and permanently bonded to the other of said second outer layer or said second inner sealant layer. 
     
     
       17. The easy open package of claim  15  wherein said second tie layer is permanently bonded both to said second outer layer and to said second inner sealant layer. 
     
     
       18. An easy open package adapted to be heat sealed to a closed condition to contain and protect product disposed therein, but which is readily openable by application of force, said package including a first package wall having a first thermoplastic polymeric film construction of a three layer coextrusion comprising a first outer layer, a first inner sealant layer of polymer and a first tie layer disposed between said first outer layer and said first inner sealant layer, said tie layer comprising a combination of polybutylene and one another constituent and being peelably bonded to only one of said first outer layer and said first inner layer and said tie layer further being permanently bonded to the other layer to which said tie layer is not peelably bonded, a second package wall joined at a portion of its perimeter to said first package wall, said second package wall having a second thermoplastic polymeric film construction with a second inner sealant layer of the same polymer as, and disposed adjacent to, said first inner sealant layer of said first film construction, a second outer layer, and a second tie layer disposed between said second outer layer and said second inner sealant layer, said second tie layer being permanently bonded both to said second outer layer and to said second inner sealant layer, whereby when said first inner sealant layer of said first film construction is heat sealed to said adjacent second inner sealant layer of said second film construction along a heat seal, a bond is formed between said inner sealant layers having greater bond strength than the peelable bond between said tie layer and said one layer of said first film construction to which said tie layer is peelably bonded such that upon application of force to open said package, the first and second inner sealant layers will remain bonded together and opening will take place between the peelably bonded layers at said heat seal.