Moisture-Curable Polyurethane Adhesive for Absorbency and Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional hot melt adhesives used in sanitary products like disposable diapers and incontinence pads suffer from poor hydrophilicity, leading to impaired absorbency and insufficient adhesive strength, particularly when liquid permeation is required.
Innovation Solution
A moisture-curable one-component adhesive composition containing a polyurethane prepolymer made from a mixture of crystalline and amorphous polyols with a polyisocyanate and a hydrophilicity imparting agent, ensuring a contact angle of 60° or less, which enhances both absorbency and adhesive strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional hot melt adhesive is used, then adhesive strength is obtained to some extent, but absorbency is not sufficient
Solution Approach 1:
The patent changes the chemical composition parameters of the adhesive by incorporating specific polyols (crystalline polyol and amorphous polyol in specific ratios) and hydrophilicity imparting agents, transforming the adhesive from hydrophobic to hydrophilic character while maintaining adhesive strength through controlled molecular structure
Solution Approach 2:
The patent creates a composite adhesive system combining multiple polyol types (crystalline and amorphous), polyisocyanate, and hydrophilicity imparting agents to achieve both adhesive strength and absorbency properties that single materials cannot provide
2Strength
If conventional hot melt adhesive is used, then bonding is achieved, but liquid permeation is hindered due to poor hydrophilicity
Solution Approach 1:
The patent fundamentally changes the hydrophilicity parameter of the adhesive by incorporating hydrophilicity imparting agents and specific polyol combinations, enabling liquid permeation while preserving bonding strength through optimized molecular structure
Solution Approach 2:
The hydrophilicity imparting agent acts as an intermediary component that bridges the hydrophobic polyurethane base and hydrophilic liquid requirements, enabling liquid permeation without compromising the adhesive bonding function
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 composition achieves an excellent balance of absorbency and adhesive strength, suitable for rapid liquid absorption in applications like disposable diapers and sanitary napkins.
Implementation Method 1
moisture-curable one-component adhesive composition
Implementation Method 2
absorbency and adhesive strength... rapid liquid absorption
Data Source
AI summary
Provided is a moisture-curable one-component adhesive composition having an excellent balance of both absorbency and adhesive strength. One aspect of the present invention is a moisture-curable one-component adhesive composition. The moisture-curable one-component adhesive composition contains a polyurethane prepolymer obtained by reacting a crystalline polyol and an amorphous polyol with a polyisocyanate, and a hydrophilicity imparting agent.