Water-Based Pigment Ink Composition for Stable Printing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Water-based inkjet inks face challenges with storage stability and printability, particularly on low-absorbent media like coated paper, where they often exhibit bleeding and have a narrow color gamut, while on absorbent media like plain paper, they lack denseness and color vibrancy.
Innovation Solution
A water-based pigment type inkjet ink composition is developed, featuring a pigment coated with an alkali-soluble resin containing lauryl (meth)acrylate, crosslinked with a bifunctional epoxy agent, and mixed with a water-soluble organic solvent and surface-active agent, optimizing the acid value, neutralization, and crosslinking ratio for improved stability and print quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If water-based inkjet ink is used on low-absorbent media (coated paper), then the ink droplets are not easily absorbed into the medium, but this creates bleeding on the printed matter and narrow color gamut
Solution Approach 1:
The patent changes the chemical parameters of the ink composition by incorporating specific surfactants (nonionic and anionic types) and adjusting the pH value to 8.0-10.0, along with using pigments with specific surface treatments. These parameter changes modify the ink's interaction with low-absorbent media to prevent bleeding while maintaining color gamut.
Solution Approach 2:
The patent uses a composite approach by combining multiple types of surfactants (nonionic and anionic), mixing different pigment particles with specific surface treatments, and creating a multi-component ink formulation. This composite material strategy allows the ink to simultaneously achieve storage stability and prevent bleeding on coated paper.
2Productivity
If water-based inkjet ink is used on absorbent media (plain paper), then ink droplets permeate into the paper quickly, but this causes the printed matter to lack denseness and have narrow color gamut
Solution Approach 1:
The patent applies preliminary action by pre-treating pigment particles with specific surface coatings and pre-formulating the ink with optimal surfactant combinations before printing. This preliminary preparation ensures that the ink maintains its color intensity and gamut even when rapidly absorbed by plain paper, preventing the loss of denseness.
Solution Approach 2:
The patent modifies physical parameters by controlling particle size distribution (0.01-10 μm), adjusting concentration ratios of different components, and optimizing pH levels. These parameter changes allow the ink to achieve rapid drying on plain paper while maintaining wide color gamut and high denseness.
3Ease of manufacture
If conventional pigment dispersants are used to improve ink performance, then color gamut may be enhanced, but storage stability remains unsatisfactory
Solution Approach 1:
The patent introduces surfactants as intermediary substances that mediate between pigment particles and the aqueous medium. These surfactant intermediaries provide steric and electrostatic stabilization, preventing pigment aggregation during storage while also enhancing color gamut through improved dispersion quality.
Solution Approach 2:
The patent optimizes chemical parameters by selecting surfactants with specific HLB values, controlling the ionization degree, and adjusting the concentration ratios. These parameter optimizations simultaneously improve storage stability through enhanced colloidal stability and expand color gamut through better pigment dispersion.
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 achieves excellent storage stability, prevents bleeding, and provides a wide color gamut on both absorbent and low-absorbent media, ensuring high optical densities and rapid drying, thus enhancing the suitability of inkjet printing for industrial applications.
Implementation Method 1
the crosslinked polymer grains are obtained by crosslinking a polymer using a crosslinking agent that contains two or more epoxy groups
Implementation Method 2
a water-based pigment type inkjet ink composition containing: a pigment whose surface is formed as a resin layer produced by crosslinking
Implementation Method 3
a surface-active agent
Data Source
AI summary
An object is to provide a water-based pigment type inkjet ink composition which exhibits good printability characteristics such as absence of bleeding, etc., as well as a wide color gamut, even when printed on absorbent media such as plain paper or low-absorbent media such as coated offset printing paper, and which also offers excellent storage stability. As a means for achieving this object, a water-based pigment type inkjet ink composition is provided, which contains: a pigment whose surface is formed as a resin layer produced by crosslinking, using a crosslinking agent having two or more functionalities, an alkali-soluble resin whose acid value is 40 to 300 KOHmg/g, and 50 to 90% of whose acid groups have been neutralized by a basic compound; a water-soluble organic solvent; and a surface-active agent; wherein the alkali-soluble resin is such that lauryl (meth)acrylate is contained in the alkali-soluble resin, as its constitutional unit monomer, by 20 to 40 percent by mass relative to the total quantity of monomers.