Elastic Skin Patch Structure for Easy Peel and Migration Barrier
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The substrate layer in existing patch sheets has high tensile elongation but high adhesion to carrier sheets, making it difficult to peel the carrier sheet from the skin, and the barrier layer's higher rigidity causes deformation or tearing when stretched or peeled.
Innovation Solution
A skin patch tape with a substrate layer, adhesive layer, and a thin barrier layer (less than 5 μm) that allows easy peeling of the carrier sheet and maintains elasticity, preventing deformation and tearing, while the barrier layer prevents active ingredient migration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the substrate layer has high tensile elongation to achieve conformability to the skin, then the conformability is improved, but the adhesion to the carrier sheet increases making it difficult to peel
Solution Approach 1:
The patent applies local quality by creating a release sheet with a specific release layer that has controlled adhesion properties only at the interface with the substrate layer. This allows the substrate layer to maintain high adhesion to the carrier sheet for conformability while the release layer provides a localized low-adhesion zone that enables easy peeling without affecting the overall adhesion performance.
Solution Approach 2:
The release sheet acts as an intermediary element between the carrier sheet and the substrate layer. It mediates the contradiction by providing a controlled release interface that allows easy peeling while the substrate layer itself maintains its high adhesion and conformability properties when applied to the skin.
2Stability of the object's composition
If the barrier layer has higher rigidity to prevent deformation, then the structural stability is improved, but the patch tape may tear when peeled from the skin
Solution Approach 1:
The patent employs a thin film approach by reducing the barrier layer thickness to less than 5 μm. This thin film maintains sufficient structural stability to prevent deformation during application while its reduced thickness and flexibility prevent tearing during peeling from the skin, resolving the contradiction between rigidity and tear resistance.
3Object-generated harmful factors
If the barrier layer thickness is increased to prevent active ingredient migration, then the barrier effectiveness is improved, but the rigidity increases causing deformation and tearing
Solution Approach 1:
The patent uses a thin film barrier layer with thickness of less than 5 μm that provides effective migration prevention through its barrier properties while maintaining flexibility. The thin film structure prevents deformation and tearing by balancing the barrier effectiveness with mechanical flexibility, avoiding the rigidity issues associated with thicker layers.
Solution Approach 2:
The barrier layer is constructed using composite material principles, combining materials that provide effective migration prevention with those that maintain flexibility. This composite approach allows the thin barrier layer to achieve both barrier effectiveness and mechanical flexibility, preventing both migration and deformation.
Data Source
AI summary
A patch tape includes a substrate layer in contact with a carrier sheet, an adhesive layer containing an active ingredient for skin and an adhesive, and a barrier layer located between the substrate layer and the adhesive layer and having a thickness of less than 5 μm. The patch tape is attached to the skin after the release sheet is peeled from the adhesive layer. The 180° peeling strength according to JIS Z 0237:2009 between the carrier sheet and the substrate layer is 550 mN/25 mm or less. In the patch tape, the tensile elongation at break according to JIS K 7161-1:2014 is 130% or more.