Method for Making A Flexible Packaging Structure With A Built-In Opening and Reclose Feature

Abstract

A flexible packaging laminate is formed to have a built-in opening and reclose feature by forming the laminate as a two-part structure having an outer structure joined in face-to-face relation with an inner structure. Score lines are formed in both structures to enable an opening to be formed through the laminate by lifting an opening portion (e.g., a flap or the like) of the two structures out of the plane of the laminate. The score line through the outer structure defines a larger opening than the score line through the inner structure, such that a marginal region of the outer structure extends beyond the edge of the opening portion of the inner structure. A pressure-sensitive adhesive is used to re-adhere the marginal region to an underlying surface of the inner structure adjacent the opening through the laminate.

1 . A flexible packaging laminate having a built-in opening and reclose feature, comprising:
 a first structure comprising at least one layer of flexible material, a pressure-sensitive adhesive substantially entirely covering one surface of the first structure; and   a second structure adhesively joined to the first structure via the pressure-sensitive adhesive so as to form a laminate having a width defined between opposite longitudinal edges thereof, the first structure and the second structure each having a width equal to the width of the laminate, respective longitudinal edges of the first and second structures being substantially coincident with each other and defining the longitudinal edges of the laminate, and the second structure comprising at least one layer of flexible material, wherein one of the first and second structures comprises an outer structure and the other comprises an inner structure;   an outer score line formed through the thickness of the outer structure and an inner score line formed through the thickness of the inner structure, the outer score line delineating an outer opening portion of the outer structure that is separable from the outer structure along the outer score line, the inner score line delineating an inner opening portion of the inner structure that is affixed to the outer opening portion by the pressure-sensitive adhesive and is separable from the inner structure along the inner score line, wherein a region of the outer opening portion between the outer and inner score lines is attached to an underlying surface of the inner structure via the pressure-sensitive adhesive, the outer opening portion being peelable from the underlying surface of the inner structure so as to cause the inner opening portion to also be peeled back to create an opening in the laminate, and the outer opening portion being re-attachable to the underlying surface of the inner structure via the pressure-sensitive adhesive for reclosing the opening.   
     
     
         2 . The flexible packaging laminate of  claim 1 , wherein the score lines are generally U-shaped such that the outer and inner opening portions form a flap that remains attached to the laminate along a hinge extending between legs of the U-shaped score lines. 
     
     
         3 . The flexible packaging laminate of  claim 1 , wherein the surface of the outer structure in contact with the pressure-sensitive adhesive is a corona or flame-treated to enhance bonding affinity with the pressure-sensitive adhesive such that the pressure-sensitive adhesive tends to remain adhered to the outer opening portion and to detach from the underlying surface of the inner structure when the opening portions are peeled back. 
     
     
         4 . The flexible packaging laminate of  claim 1 , wherein the outer structure is formed of a material that has a greater bonding affinity to the pressure-sensitive adhesive than does the inner structure. 
     
     
         5 . The flexible packaging laminate of  claim 4 , wherein the outer structure is formed of polyester and the inner structure has a layer of polyolefin forming the underlying surface to which the pressure-sensitive adhesive is attached and re-attached. 
     
     
         6 . The flexible packaging laminate of  claim 1 , wherein the inner structure is a coextruded web comprising a barrier layer and a sealant layer. 
     
     
         7 . The flexible packaging laminate of  claim 1 , wherein the inner structure has a barrier layer facing the outer structure and a sealant layer on an opposite side of the barrier layer from the outer structure, and a metallization layer disposed on the barrier layer facing the outer structure. 
     
     
         8 . The flexible packaging laminate of  claim 1 , further comprising a tamper-evidence feature formed in the laminate such that initial opening of the built-in opening and reclose feature causes the tamper-evidence feature to be visible adjacent the opening in the laminate. 
     
     
         9 . The flexible packaging laminate of  claim 8 , wherein the tamper-evidence feature comprises an area of said region of the outer opening portion treated to readily release from ink, and ink printed onto said region over said area, the ink being beneath the pressure-sensitive adhesive. 
     
     
         10 . The flexible packaging laminate of  claim 8 , wherein the tamper-evidence feature comprises printed matter on the laminate, the printed matter extending across the outer score line such that it is difficult to achieve perfect registration of the printed matter across the outer score line when reclosing the package. 
     
     
         11 . The flexible packaging laminate of  claim 1 , wherein a region of the one surface of the first structure is an adhesive-free region that is free of pressure-sensitive adhesive, the adhesive-free region forming a grasping portion of the outer opening portion. 
     
     
         12 . A package for products, comprising a flexible packaging structure initially shaped as a flat sheet and then manipulated into a tubular wrapper, opposite longitudinal edges of the wrapper being sealed together, opposing portions of the wrapper being sealed together along transverse seal lines adjacent opposite ends of the wrapper to enclose the products in the wrapper, the package having a major surface, wherein the flexible packaging structure that forms the wrapper comprises:
 a first structure comprising at least one layer of flexible material, a pressure-sensitive adhesive substantially entirely covering one surface of the first structure; and   a second structure adhesively joined to the first structure via the pressure-sensitive adhesive so as to form a laminate having a width defined between opposite longitudinal edges thereof, the first structure and the second structure each having a width equal to the width of the laminate, respective longitudinal edges of the first and second structures being substantially coincident with each other and defining the longitudinal edges of the laminate, and the second structure comprising at least one layer of flexible material, wherein one of the first and second structures comprises an outer structure and the other comprises an inner structure;   an outer score line formed through the thickness of the outer structure and an inner score line formed through the thickness of the inner structure, the outer score line delineating an outer opening portion of the outer structure that is separable from the outer structure along the outer score line, the inner score line delineating an inner opening portion of the inner structure that is affixed to the outer opening portion by the pressure-sensitive adhesive and is separable from the inner structure along the inner score line, wherein a region of the outer opening portion between the outer and inner score lines is attached to an underlying surface of the inner structure via the pressure-sensitive adhesive, the outer opening portion being peelable from the underlying surface of the inner structure so as to cause the inner opening portion to also be peeled back to create an opening in the laminate, and the outer opening portion being re-attachable to the underlying surface of the inner structure via the pressure-sensitive adhesive for reclosing the opening;   wherein the outer score line is contained within the major surface of the wrapper.   
     
     
         13 . The package of  claim 12 , wherein the major surface containing the outer score line is a top surface of the package. 
     
     
         14 . The package of  claim 13 , wherein the outer and inner score lines are configured such that the score lines bound an area constituting a majority of the total surface area of the top surface. 
     
     
         15 . A package configured as a stand-up pouch, the pouch having a major surface, the pouch being formed by a flexible packaging structure comprising:
 a first structure comprising at least one layer of flexible material, a pressure-sensitive adhesive substantially entirely covering one surface of the first structure; and   a second structure adhesively joined to the first structure via the pressure-sensitive adhesive so as to form a laminate having a width defined between opposite longitudinal edges thereof, the first structure and the second structure each having a width equal to the width of the laminate, respective longitudinal edges of the first and second structures being substantially coincident with each other and defining the longitudinal edges of the laminate, and the second structure comprising at least one layer of flexible material, wherein one of the first and second structures comprises an outer structure and the other comprises an inner structure;   an outer score line formed through the thickness of the outer structure and an inner score line formed through the thickness of the inner structure, the outer score line delineating an outer opening portion of the outer structure that is separable from the outer structure along the outer score line, the inner score line delineating an inner opening portion of the inner structure that is affixed to the outer opening portion by the pressure-sensitive adhesive and is separable from the inner structure along the inner score line, wherein a region of the outer opening portion between the outer and inner score lines is attached to an underlying surface of the inner structure via the pressure-sensitive adhesive, the outer opening portion being peelable from the underlying surface of the inner structure so as to cause the inner opening portion to also be peeled back to create an opening in the laminate, and the outer opening portion being re-attachable to the underlying surface of the inner structure via the pressure-sensitive adhesive for reclosing the opening;   wherein the outer score line is contained within the major surface of the pouch.   
     
     
         16 . The package of  claim 15 , wherein the major surface containing the outer score line is a side surface of the pouch. 
     
     
         17 . The package of  claim 16 , wherein the outer and inner score lines are configured such that the score lines bound an area constituting a majority of the total surface area of the side surface. 
     
     
         18 . A lid for a container, the lid comprising a flexible packaging structure, the flexible packaging structure comprising:
 a first structure comprising at least one layer of flexible material, a pressure-sensitive adhesive substantially entirely covering one surface of the first structure; and   a second structure adhesively joined to the first structure via the pressure-sensitive adhesive so as to form a laminate having a width defined between opposite longitudinal edges thereof, the first structure and the second structure each having a width equal to the width of the laminate, respective longitudinal edges of the first and second structures being substantially coincident with each other and defining the longitudinal edges of the laminate, and the second structure comprising at least one layer of flexible material, wherein one of the first and second structures comprises an outer structure and the other comprises an inner structure;   an outer score line formed through the thickness of the outer structure and an inner score line formed through the thickness of the inner structure, the outer score line delineating an outer opening portion of the outer structure that is separable from the outer structure along the outer score line, the inner score line delineating an inner opening portion of the inner structure that is affixed to the outer opening portion by the pressure-sensitive adhesive and is separable from the inner structure along the inner score line, wherein a region of the outer opening portion between the outer and inner score lines is attached to an underlying surface of the inner structure via the pressure-sensitive adhesive, the outer opening portion being peelable from the underlying surface of the inner structure so as to cause the inner opening portion to also be peeled back to create an opening in the laminate, and the outer opening portion being re-attachable to the underlying surface of the inner structure via the pressure-sensitive adhesive for reclosing the opening.   
     
     
         19 . The package of  claim 18 , wherein the outer and inner score lines are configured such that the score lines bound an area constituting a majority of the total surface area of the lid.