Roughened Grip Layer for Residue-Free Adhesive Strip Removal
Solution Overview
Problem
Existing pressure-sensitive adhesive products struggle with easy removal from surfaces, especially sensitive and splittable ones like plaster, wallpaper, and painted surfaces, due to slippery handle films, leading to unintended detachment and damage during the removal process.
Innovation Solution
A pressure-sensitive adhesive strip with a grip layer having a thickness of up to 50 µm and roughness of 0.10 to 2.00 µm, featuring a butadiene-vinylaromatic block copolymer elastomer component, ensuring a strong bond and improved grip, which remains securely attached to the surface during removal without leaving residue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a siliconized PET film is used as a grip layer, then the handle can be prevented from tearing off from the rest of the strip under load, but the handle film becomes too slippery and can be easily removed unintentionally from the adhesive
Solution Approach 1:
The patent applies parameter changes by modifying the surface properties of the grip layer through roughening treatment. The grip layer surface is roughened to achieve a roughness Ra of 0.05 to 0.5 µm, which transforms the slippery surface into a grippable surface while preserving the underlying material's tear strength properties.
Solution Approach 2:
The patent employs composite materials by combining the siliconized PET film base material with a surface roughening treatment. This creates a composite structure where the bulk material provides mechanical strength and tear resistance, while the modified surface layer provides enhanced grip through increased surface friction.
2Ease of operation
If the handle film is slippery towards the user, then accidental removal during use is facilitated, but interruption in the removal process causes adhesive to relax and re-adhere to sensitive surfaces causing damage
Solution Approach 1:
The patent modifies the friction parameter of the handle film surface through roughening treatment. This parameter change ensures that the film can be intentionally removed with controlled force while preventing accidental slippage during the removal process, thereby avoiding interruptions that could cause re-adhesion and surface damage.
3Reliability
If a rigid film with significantly less stretchability is used as handle material, then firm anchoring on adhesive is achieved, but the adhesive bond is exposed to high mechanical loads and deformation leading to tearing
Solution Approach 1:
The patent optimizes the flexibility parameter of the grip layer by selecting appropriate material properties and thickness (10 to 50 µm). This allows the grip layer to maintain firm anchoring while accommodating the stretching and deformation of the underlying adhesive bond without causing tearing.
Solution Approach 2:
The patent employs a thin film structure (10 to 50 µm thickness) that is flexible enough to deform with the adhesive bond during stretching. This thin film approach allows the handle material to remain firmly anchored while preventing stress concentration that would lead to tearing of the adhesive bond.
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 adhesive strip provides a secure and residue-free removal from various surfaces, including sensitive ones, with enhanced tear strength and ozone resistance, reducing the risk of damage and improving handling and adhesion.
Implementation Method 1
an improvement in the grip of the handle material is desired for improved handling in the removal process
Implementation Method 2
the adhesive strip in the handle area on at least one side is provided with a grip layer
Data Source
Figure 1~2
Figure 3
AI summary
A self-adhesive strip comprising at least one layer of adhesive compound, having a gripping area at which the adhesive strip can be detached by stretching and pulling, and which is provided with a gripping layer on at least one side in the gripping area, wherein the gripping layer has a thickness of at most 50 µm and a roughness of Sa 0.10 to 2.00 µm on at least one side, and wherein the release force of the gripping layer from the adhesive layer is at least 1 N/cm, and wherein at least one of the at least one adhesive layer comprises at least one elastomer component of the type of a butadiene-vinyl aromatic block copolymer, wherein the at least one elastomer component comprises at least 90 wt.-%, based on the total block copolymer content, consists of at least one polybutadiene-vinyl aromatic block copolymer, wherein the at least one polybutadiene-vinyl aromatic block copolymer contains polymer blocks predominantly formed by polymerization of vinyl aromatics (A-blocks), preferably styrene, and those predominantly formed by polymerization of 1,3-butadiene (B-blocks), is a relaxing, stretchable pressure-sensitive adhesive product that can be removed without residue from even sensitive and cleavable surfaces using the handle.