Double-Sided PSA Sheet Smooth Surface via Non-Woven Substrate Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional double-sided pressure-sensitive adhesive (PSA) sheets produced using the direct method often suffer from surface roughness due to air bubble formation during the drying process, which impairs the smoothness and adhesive performance of the PSA layers.
Innovation Solution
A double-sided PSA sheet is produced using a non-woven fabric substrate with specific thickness, bulk density, and air resistance characteristics, which suppresses air bubble formation when an aqueous dispersion-type PSA composition is applied and dried, resulting in a highly smooth adhesive surface. This method involves applying the PSA composition directly to the substrate, eliminating the need for a transfer substrate and reducing production costs and waste.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the direct method is used to form a PSA layer by applying aqueous dispersion-type PSA composition to a non-woven fabric substrate and allowing it to dry, then production costs and waste amounts are reduced and productivity is improved, but air bubbles form during drying which impair surface smoothness
Solution Approach 1:
The invention changes the physical parameters of the non-woven fabric substrate, specifically controlling its thickness (15-70 μm) and bulk density (0.3-0.6 g/cm³), to optimize the drying process and prevent air bubble formation while maintaining the direct method's productivity advantages
Solution Approach 2:
The invention performs preliminary preparation of the non-woven fabric substrate with specific thickness and bulk density characteristics before applying the PSA composition, ensuring that the substrate is pre-configured to allow smooth drying without air bubble entrapment
2Ease of manufacture
If the direct method is used to form a PSA layer, then production costs and waste amounts are reduced, but air bubbles form during drying which impair surface smoothness
Solution Approach 1:
The invention optimizes the physical parameters of the non-woven fabric substrate (thickness: 15-70 μm, bulk density: 0.3-0.6 g/cm³) to enable the direct method to produce smooth surfaces without requiring expensive transfer substrates or additional processing steps
3Object-affected harmful factors
If aqueous dispersion-type PSA composition is used instead of solvent-type, then environmental concerns are addressed and VOC emissions are reduced, but adhesive performance may be compromised
Solution Approach 1:
The invention changes the composition type from solvent-based to aqueous dispersion-type PSA, eliminating VOC emissions while using controlled drying conditions and optimized substrate parameters to maintain adhesive performance
Solution Approach 2:
The invention uses water as the dispersion medium instead of organic solvents, leveraging water's properties to provide an environmentally friendly carrier that evaporates without harmful VOCs while still enabling effective adhesive delivery
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 method achieves a highly smooth adhesive surface with improved adhesive performance, reduced production costs, and increased productivity, while using an environmentally friendly aqueous dispersion-type PSA composition.
Implementation Method 1
air resistance (Gurley): 1.0 to 3.0 seconds
Implementation Method 2
applying the PSA composition to at least one of the two sides of the non-woven fabric substrate and allowing the applied composition to dry
Data Source
AI summary
Provided are a double-sided PSA sheet comprising a PSA layer formed by directly applying an aqueous dispersion-type PSA composition to a non-woven fabric substrate, wherein the layer has a highly smooth surface; and a method for producing the same. In this method, an aqueous dispersion-type PSA composition is applied to at least a first side of the non-woven fabric substrate and the composition is allowed to dry to form a PSA layer. A non-woven fabric of 15 µm to 70 µm in thickness, 0.3 to 0.6 g/cm3 in bulk density, and 0.7 sec to 2 sec in air resistance (Gurley) when measured for 8 layers the non-woven fabric substrate is used as the non-woven fabric substrate.