Two-Component Solventless Polyurethane Adhesives for Fast Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Solventless laminating adhesives face issues such as slow bond development, slow primary aromatic amine (PAA) decay, low adhesion to metal surfaces, ink smearing, and poor chemical and thermal resistance, particularly in demanding applications, limiting their use in high-speed processing and compliance with regulations.
Innovation Solution
A two-component solventless polyurethane adhesive composition comprising an isocyanate-terminated prepolymer, polyether polyol, phosphate ester adhesion promoter, and bio-based polyol, which enhances adhesion to metalized films and improves curing speed and chemical resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If solventless laminating adhesives are used, then environmental compliance and health safety are improved, but bond development speed and PAA decay rate deteriorate
Solution Approach 1:
The patent modifies the chemical composition parameters of the adhesive by incorporating specific catalysts (metal salts like zinc stearate, calcium stearate), adhesion promoters (phosphate esters, silanes), and polyol blends (polyester polyol, polyether polyol, bio-based polyols) to accelerate the curing reaction kinetics while maintaining the solventless formulation for environmental compliance
Solution Approach 2:
The adhesive uses a composite polyol system combining multiple polyol types (polyester, polyether, bio-based) with complementary properties to achieve both fast curing and strong adhesion, while the isocyanate component is blended with catalysts and adhesion promoters to create a multi-functional composite adhesive material
2Reliability
If solventless laminating adhesives are used, then chemical resistance is improved, but adhesion to metal surfaces deteriorates
Solution Approach 1:
The patent introduces adhesion promoters (phosphate esters, silanes, carboxylic acids) as intermediary substances that form chemical bridges between the adhesive and metal substrates, improving metal surface adhesion without compromising the chemical resistance provided by the solventless polyurethane matrix
Solution Approach 2:
The adhesive composition is adjusted by incorporating metal-specific adhesion promoters and optimizing the polyol blend ratio to enhance affinity for metal surfaces while maintaining the cross-linked network structure that provides chemical resistance
3Strength
If two-component polyurethane adhesive is used, then adhesion to various substrates is improved, but curing time increases
Solution Approach 1:
The patent incorporates catalysts (metal salts, organic compounds) that accelerate the isocyanate-polyol reaction kinetics, reducing curing time while maintaining the two-component system's superior adhesion properties across diverse substrates
Solution Approach 2:
The adhesive components are pre-formulated with optimized ratios of polyols, catalysts, and adhesion promoters, allowing the mixture to be ready for immediate application with predictable and accelerated curing characteristics
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 faster curing, quicker PAA decay, better metalized film adhesion, enhanced foil adhesion, and increased chemical and thermal resistance, making it suitable for high-speed processing and compliance with food contact regulations.
Implementation Method 1
a phosphate ester adhesion promoter, and, a bio-based polyol. The disclosed adhesive compositions exhibit improved properties over current solventless adhesive systems, for example - faster curing than current systems, quicker primary aromatic amine ('PAA') decay, better adhesion to metalized films
Implementation Method 2
The disclosed adhesive compositions comprise an isocyanate component comprising an isocyanate-terminated prepolymer, and an isocyanate-reactive component comprising a polyether polyol
Implementation Method 3
The two components are combined in a predetermined ratio and then applied on a first substrate (also known as a 'carrier web'). The first substrate is then brought together with a second substrate to form a laminate structure. The adhesive is then cured, either at room temperature or elevated temperature, thereby bonding the substrates together
Data Source
AI summary
Two-component solventless polyurethane adhesive compositions comprising an isocyanate component and an isocyanate-reactive component are disclosed, the compositions comprising an isocyanate component comprising an isocyanate-terminated prepolymer, and an isocyanate-reactive component comprising a polyether polyol, a phosphate ester adhesion promoter, and, a bio-based polyol. Methods for forming laminate structures are also disclosed, the methods comprising forming an adhesive composition by mixing an isocyanate adhesive component comprising an isocyanate-terminated prepolymer and an isocyanate-reactive adhesive component comprising a polyether polyol, a phosphate ester adhesion promoter, and a bio-based polyol, applying the adhesive composition to a surface of a first substrate, and bringing a surface of a second substrate into contact with the adhesive composition on the surface of the first substrate, thereby forming the laminate structure. Laminate structures are also disclosed.