Structured Packaging Film Prevents Adhesive Cold Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transdermal therapeutic systems face issues with adhesive material 'cold flow' during storage, leading to sticking to packaging surfaces, which complicates handling and increases costs, and existing solutions like spacers or coated films are either ineffective or complex to integrate.
Innovation Solution
A packaging material with micro- and nanostructured surfaces, featuring recesses and non-recessed areas with specific dimensions, is used to prevent adhesive sticking, where the structured surface facing away from the adhesive layer is heat-sealed with a second material to create a moisture, gas, and aroma-tight joint.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a smooth packaging material surface is used, then the packaging material provides good sealing and protective properties, but the adhesive material sticks to the packaging surface during storage
Solution Approach 1:
The packaging material surface is structured with recesses and non-recessed areas to create local variations in surface properties. The non-recessed areas provide smooth sealing surfaces while the recesses prevent adhesive sticking, allowing different regions of the surface to fulfill different functions.
Solution Approach 2:
The continuous packaging material surface is segmented into numerous small recesses and non-recessed areas. This segmentation creates a heterogeneous surface topology that prevents adhesive material from forming continuous contact with the packaging surface, thereby preventing sticking while maintaining overall sealing integrity.
2Object-generated harmful factors
If nubs are punched into the protective film as spacers, then adhesive sticking is prevented, but the nubs are deformed by clamping jaws during conveyance and become unusable
Solution Approach 1:
Instead of adding protruding elements (nubs) to prevent sticking, the invention inverts the approach by creating recesses in the packaging material surface. This inverted geometry passively prevents adhesive contact without requiring fragile protruding structures that can be deformed during handling.
3Object-generated harmful factors
If an overhanging coated protective film is used to prevent adhesive sticking, then sticking is prevented, but the solution requires technically complex integration into the manufacturing process and additional disposal steps
Solution Approach 1:
The anti-sticking function is merged into the packaging material itself through surface structuring, rather than being implemented as a separate overhanging film. This integration eliminates the need for additional manufacturing steps to apply and remove separate protective films, simplifying the overall process while maintaining the anti-sticking effect.
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 structured surface effectively reduces adhesive bonding with the packaging material, preventing sticking and facilitating easy removal of the transdermal therapeutic system without residue, while maintaining packaging integrity and aesthetics.
Implementation Method 1
the entire packaging material surface having a large number of recesses and/or a large number of non-recessed areas, where the distance between two adjacent recesses is less than one micrometer and/or the distance between two adjacent non-recessed areas is less than one micrometer and where the depth of the recesses is at least 1.2 nanometers and at most 95% of the thickness of the packaging material
Implementation Method 2
This first packaging material is connected to a second packaging material, which is arranged on the side of the transdermal therapeutic system facing the adhesive-containing layer, by means of heat sealing. This creates a moisture, gas and aroma-tight joint.
Data Source
AI summary
The invention relates to a web of packaging material which comprises at least one layer of a sealable material that comprises a packaging material surface, to a packaging unit with a transdermal therapeutic system and said packaging material and to a method for producing a packaging unit. The packaging material according to the invention is characterized in that at least one surface of the packaging material has a plurality of recesses and/or a plurality of non-recessed portions. The distance of two adjacent recesses and/or the distance of two adjacent non-recessed portions is less than five times the film thickness. The depth of the recesses is not less than 1.2 nanometer and not more than 95% of the film thickness. The packaging material according to the invention effectively prevents an adhesive from sticking to the interior of the packaging material.