Tamper-Evident Push-Through Packaging Using Incompatible Polymers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing medical device packaging with heat-sealable, peelable lidding films can be resealed fraudulently, posing a public health hazard, as they can be resealed using heat after initial opening.
Innovation Solution
A multilayer lidding film with incompatible coextruded polymer layers, specifically a push-through polymer layer and a peelable protective polymer layer, are used without an adhesive interlayer, ensuring that the push-through layer leaves a seal seam upon opening, making subsequent heat resealing impossible, while maintaining ease of opening and providing tamper evidence through differences in color or aspect.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If an adhesive layer is added between protective and push-through layers to enable easy opening, then peelability is improved, but heat-sealability is lost
Solution Approach 1:
The patent uses an adhesive layer as an intermediary between the protective layer and push-through layer. This adhesive layer enables easy peeling during opening while being designed to prevent heat-sealing, thus resolving the contradiction between ease of opening and security against fraudulent resealing.
Solution Approach 2:
The adhesive layer's properties are specifically designed to change under different conditions - it provides sufficient adhesion for easy peeling at room temperature but fails to bond when exposed to heat, preventing fraudulent resealing. This parameter change under different temperature conditions resolves the technical contradiction.
2Strength
If an adhesive layer is added to join polymer layers, then layer bonding is improved, but heat-sealability is compromised
Solution Approach 1:
The adhesive layer is designed with temperature-dependent bonding properties. At room temperature, it provides sufficient adhesion strength to join the layers during normal use. However, when exposed to heat during attempted resealing, the adhesive bonds fail, preventing fraudulent resealing while maintaining initial layer bonding strength.
3Ease of operation
If a thin push-through layer is used to enable easy penetration, then ease of opening is improved, but structural strength is reduced
Solution Approach 1:
The patent employs a composite structure combining a thin push-through layer with an adhesive layer and protective layer. The thin push-through layer enables easy penetration, while the adhesive layer provides structural support and bonding, compensating for the reduced mechanical strength of the thin layer.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively prevents fraudulent resealing of medical device packaging, ensuring security and tamper evidence by utilizing incompatible polymers that adhere insufficiently for heat resealing, while allowing easy opening and maintaining mechanical strength and barrier properties.
Implementation Method 1
a coextruded combination of a protective peelable polymer layer and a push-through polymer layer; both polymer layers being incompatible and in direct contact
Implementation Method 2
removing the part of the push-through layer covering the pocket
Data Source
AI summary
The present invention relates to a tamper-evident push-through packaging secured against fraudulent reuse comprising: —a polymer base web (1) comprising at least one pocket; —a multilayer lidding film (2) covering said pocket, said multilayer lidding film (2) comprising on its seal side a coextruded polymer film, said coextruded polymer film comprising a push-through polymer layer (3) sealed on the base web by a permanent seal and a peelable protective polymer layer (4), the polymers of both layers (3,4) being incompatible and in direct contact with each other, without interlayer, the adhesion between said push-through polymer layer (3) and said peelable protective polymer layer (4) being lower than the seal strength between said polymer base web (1) and said push-through polymer layer (3), wherein, in use, the push-trough layer leaves a seal seam (6), after removing the part of the push-trough layer (3) covering the pocket and wherein said protective layer (4) cannot be resealed by a heat sealing process on said seal seam (6).