Active-Energy Ray Curable Offset Ink Gloss Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Active energy ray-curable ink compositions for offset printing result in printed matter with low gloss due to rapid viscosity increase, which impairs leveling and appearance.
Innovation Solution
Incorporating specific liquid materials with ethylenically unsaturated bonds and photopolymerization initiators, along with additional compounds lacking ethylenically unsaturated bonds, to adjust the SP value and enhance leveling properties, as defined by Conditions (A), (B), and (C), to maintain flowability and achieve superior gloss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If active energy ray-curable ink composition is used for offset printing, then drying speed is improved, but gloss is worsened
Solution Approach 1:
The patent applies parameter changes by carefully controlling the viscosity of the ink composition within a specific range (100-500 cP at 25°C) and adjusting the content of polymerizable compounds and non-polymerizable compounds to achieve optimal balance between drying speed and gloss. This parameter optimization allows the ink to maintain flowability for leveling while enabling rapid curing upon irradiation
Solution Approach 2:
The patent uses composite materials by combining polymerizable compounds (monomers and oligomers) with non-polymerizable compounds in specific ratios. This composite formulation creates an ink composition that maintains appropriate viscosity and flowability before irradiation, then cures rapidly to provide both fast drying and high gloss appearance
2Loss of time
If polymerizable compounds are rapidly polymerized by active energy rays, then drying time is reduced, but flowability is worsened
Solution Approach 1:
The patent applies partial action by using a combination of polymerizable compounds (which will polymerize upon irradiation) and non-polymerizable compounds (which remain as flowability agents). This partial polymerization approach ensures that sufficient non-polymerizable compounds remain in the system to maintain flowability and leveling, while still achieving rapid drying through the polymerization of the polymerizable portion
Solution Approach 2:
The patent controls the viscosity parameter within a narrow optimal range (100-500 cP) by adjusting the ratio and types of polymerizable and non-polymerizable compounds. This parameter control ensures the ink remains fluid enough for leveling but can rapidly increase in viscosity upon irradiation to achieve fast drying
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 ink composition effectively maintains flowability and enhances the gloss of printed matter, ensuring superior appearance and commercial value by optimizing the content of materials with specific SP values and properties.
Implementation Method 1
Such types of ink compositions contain polymerizable compounds, such as monomers or oligomers, and polymerization initiators that can polymerize the polymerizable compounds by irradiation with active energy rays, such as ultraviolet rays or electron beams
Data Source
AI summary
Provided is an active energy ray-curable ink composition for offset printing capable of achieving superior gloss of printed matter. The ink composition comprises a compound having at least one ethylenically unsaturated bond and a photopolymerization initiator, wherein a group of materials having no ethylenically unsaturated bonds, having a specified SP value, and exhibiting a liquid state at room temperature is added to the ink composition up to the upper limit depending on the SP value. Examples of such a group of materials include castor oil, hardened castor oil, polymerized castor oil, coconut oil, palm kernel oil, epoxidized fats and oils, alkylphenols having C15-C18 alkyl groups, cashew nut shell liquid, polymers of cashew nut shell, and modified derivatives of cashew nut shell liquid.