Green Inkjet Pigment Dispersion Agglomeration Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing inkjet printing technologies face challenges in maintaining small particle sizes of green organic pigments, particularly copper phthalocyanine pigments, as they tend to agglomerate during milling, and struggle to expand the color gamut beyond what is possible with these pigments alone.
Innovation Solution
Aqueous green inkjet ink compositions are developed, comprising a combination of green copper phthalocyanine pigment and azo-coupled β-ketoamide pigment, with a specific weight ratio and the addition of organic pigment dispersants, which helps maintain particle stability and prevent agglomeration, allowing for expanded color gamut and improved shelf life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If green copper phthalocyanine pigment is milled to reduce particle size, then particle size is reduced, but particles agglomerate during milling
Solution Approach 1:
The patent uses an azo-coupled β-ketoamide pigment as an intermediary substance that prevents agglomeration of copper phthalocyanine particles during milling. This intermediary pigment acts as a spacer or barrier between the green pigment particles, maintaining their separation and stability throughout the milling process while allowing achievement of small particle sizes.
Solution Approach 2:
The invention creates a composite pigment system combining copper phthalocyanine pigment with azo-coupled β-ketoamide pigment in specific weight ratios. This composite approach allows the two different pigment materials to work together, where the β-ketoamide pigment provides steric stabilization that prevents agglomeration of the phthalocyanine particles during mechanical milling.
2Adaptability or versatility
If only green copper phthalocyanine pigment is used, then particle stability is maintained, but color gamut is limited
Solution Approach 1:
The patent merges two different pigment substances - copper phthalocyanine and azo-coupled β-ketoamide - into a single inkjet composition. This combining allows the formulation to achieve expanded color gamut through the complementary color properties of the two pigments while maintaining practical particle stability through their synergistic interaction during milling.
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 solution achieves stable particle sizes and expanded color gamut in inkjet printing, ensuring minimal agglomeration and improved color reproduction, as demonstrated by the CIELAB L*, a*, and b* values, and maintaining these properties during storage and use.
Implementation Method 1
aqueous organic pigment dispersion comprising: a green copper phthalocyanine pigment, an azo-coupled β-ketoamide pigment, and at least one organic pigment dispersant
Implementation Method 2
helps maintain particle stability and prevent agglomeration
Implementation Method 3
ink jetting an aqueous green inkjet ink composition as spaced green drops to provide a green color image on the substrate
Data Source
AI summary
Aqueous green inkjet ink compositions are prepared from aqueous organic pigment dispersions for use in various inkjet printing methods. In particular, these methods provide a green image or expanded color gamut for other inkjet printed colors. The aqueous organic pigment dispersion contains a green copper phthalocyanine pigment and an azo-coupled β-ketoamide pigment and an organic pigment dispersant. The weight ratio of the green copper phthalocyanine pigment to the azo-coupled β-ketoamide pigment is from 1:1 to 10:1. The median particle diameter of each of the green copper phthalocyanine pigment and the azo-coupled β-ketoamide pigment is less than 85 nm. At least 95% of the total particles of each of the green copper phthalocyanine pigment and the azo-coupled β-ketoamide pigment have a particle diameter of less than 150 nm.