Quinacridone Inkjet Ink Purification for Stable Head Ejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet inks containing quinacridone pigments face issues with ejection stability due to impurities like phosphorous-containing catalysts and intermediates attaching to recording head surfaces, leading to skewed ejection and reduced re-solubility.
Innovation Solution
The ink formulation includes specific phosphorous concentration and absorbance peaks to minimize these impurities, ensuring stable ejection and improved re-solubility by adjusting the concentration of phosphorous-containing catalysts and intermediates through ultrafiltration and adjusting resin content.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If quinacridone pigment is used in inkjet ink, then color fastness and image quality are improved, but phosphorous-containing catalysts and intermediates attach to recording head surfaces causing skewed ejection
Solution Approach 1:
The patent removes phosphorous-containing catalysts and intermediate substances from the ink formulation through purification processes. This extraction eliminates the harmful impurities that cause attachment to recording head surfaces while preserving the beneficial quinacridone pigment for high-quality image formation.
Solution Approach 2:
The patent modifies the chemical composition parameters of the ink by controlling the concentration and purity of quinacridone pigment and eliminating phosphorous-containing substances. This parameter change resolves the contradiction by maintaining color fastness while removing ejection instability causes.
2Manufacturing precision
If quinacridone pigment is used in inkjet ink, then image quality is improved, but re-solubility is reduced
Solution Approach 1:
The patent extracts and removes intermediate substances and impurities from the quinacridone pigment formulation. This purification process maintains the pigment's excellent color fastness and image quality while eliminating substances that reduce re-solubility, allowing the ink to be effectively cleaned from recording heads.
3Ease of manufacture
If phosphorous-containing catalysts are present in ink, then pigment synthesis is facilitated, but skewed ejection occurs due to attachment on recording head surfaces
Solution Approach 1:
The patent removes phosphorous-containing catalysts from the final ink formulation through purification processes. This extraction eliminates the cause of skewed ejection while the pigment synthesis had already been completed using these catalysts, thus maintaining ease of manufacture without compromising ejection stability.
Solution Approach 2:
The patent performs purification to remove phosphorous-containing catalysts before the ink is loaded into the recording apparatus. This preliminary action prevents the catalysts from causing skewed ejection during actual printing operations while maintaining the benefits of using catalysts during pigment synthesis.
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 inhibits skewed ink ejection, enhances image scratch resistance, and improves re-solubility of the ink, maintaining ejection stability and image quality.
Implementation Method 1
The supernatant is obtained by centrifugation of the inkjet ink at 1,050,000 G for 3 hours
Data Source
AI summary
An inkjet ink contains a quinacridone pigment, a resin, and an aqueous medium. A 50-fold dilution of a supernatant obtained by centrifugating the inkjet ink at 1,050,000 G for 3 hours has a phosphorous concentration of at least 1.0 ppm and no greater than 6.0 ppm. On an ultraviolet-visible absorption spectrum of the supernatant, a first peak appears at a first absorbance of at least 0.16 and no greater than 0.40. The first peak is a maximum peak in a wavelength range of the ultraviolet-visible absorption spectrum of at least 300 nm and no greater than 340 nm. On the ultraviolet-visible absorption spectrum of the supernatant, a second peak appears at a second absorbance of at least 0.15 and no greater than 0.80. The second peak is a maximum peak in a wavelength range of the ultraviolet-visible absorption spectrum of at least 400 nm and no greater than 490 nm.