Solvent-Free Radiation Curable Adhesive Process
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solvent-based and water-based processes for producing radiation curable adhesives face limitations, including high energy consumption, solvent emissions, and inability to achieve high molecular weight end-products within conventional curing times, while solvent-less processes lack optimization for high performance pressure sensitive adhesives.
Innovation Solution
A process involving a first copolymerization step with a non-copolymerizable cyclic compound and a subsequent ring opening step with a radiation curable compound to form a radiation curable adduct, resulting in a composition comprising (meth)acrylic copolymers and radiation curable compounds, which allows for high molecular weight formation and solvent-free production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If solvent-based processes are used to produce radiation curable adhesives, then excellent adhesive properties (peel and shear) can be achieved through precise molecular weight control and ionic cross-linking, but high energy consumption and solvent emissions occur due to large thermal drying ovens requiring long production times
Solution Approach 1:
The invention extracts and eliminates the solvent component from the adhesive system entirely, using a solvent-less hot-melt formulation that achieves high adhesive performance through alternative mechanisms (ionic cross-linking and radiation curing) without requiring thermal drying ovens, thereby resolving the contradiction between adhesive performance and energy consumption
Solution Approach 2:
The invention changes the fundamental parameter of solvent content from high (solvent-based) to zero (solvent-less), and introduces radiation curing as an alternative drying mechanism that operates at ambient or lower temperatures, thus achieving high adhesive performance without the energy-intensive thermal drying process
2Manufacturing precision
If solvent-based processes are used, then precise molecular weight control and ionic cross-linking can be achieved, but long production times and high energy consumptions are required to evaporate large volumes of solvents
Solution Approach 1:
The invention replaces the thermal evaporation mechanism (mechanical/thermal system) with radiation curing (electromagnetic radiation system), which achieves solvent removal and adhesive curing simultaneously without requiring long exposure times in thermal drying ovens, thus resolving the contradiction between manufacturing precision and production time
Solution Approach 2:
The invention enables continuous production by eliminating the sequential steps of solvent evaporation followed by adhesive curing, instead achieving both objectives simultaneously through radiation curing of the solvent-less hot-melt formulation, thereby reducing production time while maintaining molecular weight control
3Strength
If solvent-based processes are used, then excellent adhesive properties can be achieved, but residual solvents remain in the end-product leading to outgassing issues
Solution Approach 1:
The invention extracts and eliminates solvents from the adhesive formulation entirely, using a solvent-less hot-melt system that achieves high adhesive performance through ionic cross-linking and radiation curing, completely preventing residual solvent outgassing while maintaining excellent adhesive properties
Solution Approach 2:
The invention converts the potential harm of solvent emissions into a benefit by using the solvent-less formulation approach, where the absence of solvents eliminates outgassing issues entirely while the ionic cross-linking and radiation curing mechanisms provide enhanced adhesive performance
4Object-affected harmful factors
If water-based systems are used, then flammable solvent problems are overcome, but water removal is more difficult due to lower volatility
Solution Approach 1:
The invention extracts and eliminates both flammable solvents and water from the adhesive system, using a solvent-less hot-melt formulation that achieves high adhesive performance without requiring energy-intensive water evaporation, thereby resolving the contradiction between flammability safety and energy consumption
Solution Approach 2:
The invention changes the fundamental parameter of liquid carrier content from high (water-based) to zero (solvent-less), and introduces radiation curing as an alternative drying mechanism that operates without thermal evaporation, thus achieving flammability safety without the energy penalty of water removal
5Object-affected harmful factors
If conventional thermal curing is used for solvent-less hot-melt PSA's, then non-flammable formulation is achieved, but high application temperature leads to premature curing in equipment
Solution Approach 1:
The invention replaces thermal curing (thermal system) with radiation curing (electromagnetic radiation system), which enables curing of solvent-less hot-melt PSA's at ambient or lower temperatures without premature curing in equipment, thus achieving flammability safety while simplifying process control
Solution Approach 2:
The invention changes the curing mechanism from thermal (temperature-dependent) to radiation-based (wavelength-dependent), allowing the adhesive to be applied at low temperatures without premature curing and then cured on-demand using radiation, thereby achieving flammability safety and reducing device complexity
6Length of stationary object
If solvent-based or water-based systems are used, then coating can be performed, but layer thicknesses above 100 μm require multiple passes or subsequent lamination due to solvent/water removal difficulties
Solution Approach 1:
The invention extracts and eliminates solvents and water from the adhesive system, using a solvent-less hot-melt formulation that can be applied in thick layers without requiring energy-intensive evaporation, enabling single-pass coating at thicknesses above 100 μm while reducing energy consumption
Solution Approach 2:
The invention changes the fundamental parameter of liquid carrier content from high (solvent/water-based) to zero (solvent-less), and introduces radiation curing as an alternative drying mechanism that works effectively for thick layers without requiring multiple passes or subsequent lamination, thus achieving increased coating thickness with reduced energy consumption
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 process achieves radiation curable compositions with improved properties suitable for pressure sensitive adhesives, offering reduced production time, energy consumption, and solvent emissions, enabling thicker layers to be applied and cured in a single pass with enhanced peel and shear performance.
Implementation Method 1
a subsequent ring opening step, the preparation of the radiation curable compound B by the ring opening of the cyclic compound (b1) with at least one radiation curable compound (a5)
Implementation Method 2
in a first copolymerization step, the preparation of a (meth)acrylic copolymer in the presence of at least one non-copolymerizable cyclic compound (b1)
Implementation Method 3
Radiation curable PSA's show very good performance, the radiation curing process has an inherently low carbon footprint
Data Source
AI summary
The present invention relates to a process for the preparation of a radiation curable composition comprising at least one (meth)acrylic copolymer A and at least one radiation curable compound B, said process comprising a first copolymerization step, and a subsequent ring opening step.