UV-Curable Ink Primer for Lightweight Paper Substrates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional water-based inkjet inks face challenges such as high water content leading to show-through on lightweight papers, requirement of high heat for drying, limited substrate compatibility, and high costs, which hinder their adoption in commercial and industrial printing applications.
Innovation Solution
Development of UV or EB curable compositions comprising a zinc or magnesium salt of acrylic acid or methacrylic acid, with a co-monomer selected from acrylic acid, methacrylic acid, and their salts, which can be applied as primers, inks, or varnishes on various substrates without the need for external heat, reducing energy consumption and costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional water-based inkjet inks are used, then printing on lightweight papers is possible, but show-through occurs and high heat is required for drying
Solution Approach 1:
The patent changes the chemical composition parameters of the ink from water-based to UV-curable resin-based formulation. This fundamental parameter change enables the ink to cure through photopolymerization instead of thermal evaporation, eliminating the need for high heat drying while maintaining compatibility with lightweight papers and reducing show-through issues.
Solution Approach 2:
The patent replaces the thermal drying mechanism with a UV photopolymerization mechanism. Instead of using heat energy to evaporate water and dry the ink, the system uses UV light to initiate chemical curing of the resin-based ink, substituting a chemical process for a thermal-mechanical process and significantly reducing energy consumption.
2Ease of manufacture
If conventional water-based inkjet inks are used, then printing process is simple, but costs are high and substrate adhesion is limited
Solution Approach 1:
The patent employs composite material formulation by combining UV-curable resins with specialized adhesion promoters and co-monomers. This composite approach creates an ink system that maintains ease of application while achieving superior adhesion to diverse substrates including plastics, metals, and coated surfaces that conventional water-based inks cannot effectively print on.
3Adaptability or versatility
If UV inks with glycol ether solvents are used, then substrate adhesion is improved, but health risks and environmental concerns arise
Solution Approach 1:
The patent extracts and removes the harmful glycol ether solvent component from the UV ink formulation. By eliminating this toxic solvent while retaining the UV-curable resin base and adhesion promoters, the ink maintains effective substrate adhesion properties without the associated health risks and environmental concerns of VOC-containing formulations.
Solution Approach 2:
The patent changes the solvent parameter from volatile organic compounds (glycol ethers) to a solvent-free or water-based UV-curable resin system. This parameter change in the chemical composition eliminates the harmful factors associated with glycol ether solvents while preserving the ink's ability to adhere to various substrates through the resin matrix and adhesion promoters.
4Quantity of substance
If high water content inks are used, then ink cost is reduced, but show-through and drying energy requirements increase
Solution Approach 1:
The patent utilizes the phase transition principle by changing the ink from a water-based liquid that requires thermal evaporation to a UV-curable resin system that undergoes photopolymerization. This phase change in the curing mechanism eliminates the need for high water content and subsequent high-heat drying, reducing both show-through on lightweight papers and energy consumption while maintaining cost-effectiveness.
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 curable compositions provide improved energy efficiency, reduced ink consumption, enhanced substrate compatibility, including lightweight papers, and the ability to achieve high-speed curing without nitrogen blanketing, making them suitable for food-contact applications and reducing overall production costs.
Implementation Method 1
UV or electron beam (EB) curable composition
Implementation Method 2
UV or electron beam (EB) curable composition
Data Source
Figure 1
Figure 2
AI summary
The invention describes new designs of commercial inkjet or flexographic web and sheet fed presses with pre-coating prior to printing which may upgrade the quality of the substrates and render them printable by all printing technologies including inkjet and digital. Also described are curable water-based coatings, inkjet and flexographic inks and overprint varnishes which may be radiation cured at high speed without the need for external applied heat to remove water. When used as coatings or primers, the compositions of the invention may create a surface on cellulosic substrates, polymeric films and some metal surfaces which are suitable for printing on by most printing methods including but not limited to inkjet, wet and dry toner systems, lithographic, gravure, flexographic and 4-D printing. The primer/coatings may also add up to 35% tensile strength to lightweight "thin" papers. The primer/coatings, inks and overprint varnishes can be cured by UV with or without the need for added commercial and/or conventional photoinitiators and the same formulations can be cured with electron beam using less than 35% of the energy required for conventional EB coatings and inks and without the need for a nitrogen environment thus allowing EB cure sheet fed printing. The primer/coatings of the invention may allow multi-colour printing on lightweight papers by conventional water-based inkjet inks that could previously not be printed with this method. Overprint varnishes of the invention can be applied successfully in-line on the printing press over wet inks before being EB or UV cured.