Pressure-Sensitive Adhesive Composition for Re-Detachable Sheets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pressure-sensitive adhesives used for confidential postcards and information-carrying sheets face issues with uneven adhesion strength and plate clogging when used with printing machines like gravure or flexo printers, especially when the adhesive is applied after printing, leading to potential leakage of personal information during detachment.
Innovation Solution
A pressure-sensitive adhesive composition comprising a rubber latex and a water-soluble styrene-acrylic acid copolymer is applied to the sheet surfaces after printing, providing excellent storage stability and preventing plate clogging, with fine rubber particles and a water-soluble styrene-acrylic acid copolymer ensuring a homogeneous surface and balanced blocking resistance and re-detachability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a resin emulsion is used in a post-coating-type adhesive applied after printing, then stable adhesion force is achieved, but plate clogging occurs in gravure or flexo printers
Solution Approach 1:
The patent changes the chemical composition parameters of the adhesive from resin emulsion to rubber latex combined with water-soluble polymer. This parameter change maintains adhesion reliability while eliminating plate clogging issues, as rubber latex provides the necessary adhesive properties without the clogging problems associated with resin emulsions in printing machines
Solution Approach 2:
The patent uses a composite material system combining rubber latex with water-soluble polymer (styrene-acrylic acid copolymer, polyacrylic acid, or carboxymethyl cellulose). This composite approach achieves both stable adhesion force and compatibility with printing processes, resolving the contradiction between reliability and ease of manufacture
2Ease of manufacture
If adhesive is applied before printing (pre-coating), then coating process is simple, but adhesion strength becomes uneven and printing area varies
Solution Approach 1:
The patent applies the adhesive after printing rather than before, which is a preliminary action to ensure the printing surface is fully formed. This timing ensures uniform adhesion strength across the entire printed area while maintaining a simple coating process, as the adhesive is applied to the already-printed surface without interfering with the printing process
3Quantity of substance
If printed area increases in confidential postcards, then information capacity increases, but adhesive-applied area decreases and adhesion strength becomes insufficient
Solution Approach 1:
The patent changes the adhesive composition parameters to use rubber latex with water-soluble polymer, which provides superior adhesion strength that can cover larger printed areas. This parameter change allows increased information capacity while maintaining sufficient adhesion strength across the entire surface, even when adhesive-applied area is reduced
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 achieves stable adhesion and re-detachability without breaking the paper, maintains transparency of printed surfaces, and prevents plate clogging during printing, ensuring secure and efficient use of information-carrying sheets with improved designability and reduced environmental impact.
Implementation Method 1
pressure-sensitive adhesive composition... being applied to a first sheet surface and a second sheet surface after printing, being dried, and then press-bonding the first sheet surface and the second sheet surface together so as to closely adhere
Implementation Method 2
pressure-sensitive adhesive composition... providing excellent storage stability and preventing plate clogging, with fine rubber particles and a water-soluble styrene-acrylic acid copolymer ensuring a homogeneous surface and balanced blocking resistance and re-detachability
Data Source
AI summary
According to the present invention, there is provided a pressure-sensitive adhesive composition for forming a re-detachable sheet by being applied to a first sheet surface and a second sheet surface after printing, being dried, and then press-bonding the first sheet surface and the second sheet surface together so as to closely adhere the first sheet surface and the second sheet surface, including a rubber latex and a water-soluble styrene-acrylic acid copolymer.