Ink Composition Polymeric Dispersant Nozzle Debris
Solution Overview
Problem
Inkjet printheads accumulate debris at nozzle ejection sites, which interferes with ink ejection, contaminates fresh ink, and affects print quality, necessitating an ink composition that minimizes or prevents debris formation.
Innovation Solution
An aqueous dye inkjet ink composition comprising a polymeric dispersant with a hydrophobic and hydrophilic segment, specifically an acrylic polymer with methacrylic acid, poly(propylene glycol)-4 nonphenyl ether acrylate, and poly(ethylene glycol)2, 4, 6,-tris-(1-phenylethyl) phenyl ether methacrylate, that agglomerates debris through its detergent effect, preventing buildup and improving printhead performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional ink compositions are used, then inkjet printing can be performed, but debris accumulates at nozzle ejection sites interfering with ink ejection and print quality
Solution Approach 1:
The patent introduces a polymeric dispersant as an intermediary substance in the ink composition. This dispersant has hydrophobic segments that adsorb onto debris particles and hydrophilic segments that extend into the aqueous medium, creating steric barriers that prevent debris aggregation and facilitate its removal from nozzle surfaces, thereby resolving the debris accumulation problem without affecting inkjet printing functionality
Solution Approach 2:
The patent modifies the chemical composition parameters of the ink by incorporating specific polymeric dispersants with controlled molecular weights, hydrophobic-hydrophilic segment ratios, and functional group compositions. These parameter changes enable the ink to actively manage debris through detergent effects and steric stabilization, transforming the ink from a passive medium to an active debris-management system that maintains printhead reliability
2Object-generated harmful factors
If polymeric dispersant is added to ink composition, then debris is reduced at nozzle ejection sites, but ink composition complexity increases
Solution Approach 1:
The patent employs composite polymeric dispersants consisting of multiple segments with different functions (hydrophobic adsorption segments, hydrophilic stabilization segments, and spacer segments). This composite structure allows a single additive to perform multiple functions: debris adsorption, steric stabilization, and solubility maintenance, thereby reducing debris accumulation without proportionally increasing composition complexity
Solution Approach 2:
The polymeric dispersant is designed with multi-functionality, serving as simultaneously a surfactant, stabilizer, and debris-removal agent. The hydrophobic portions provide detergent effects for debris removal, while the hydrophilic portions provide steric stabilization and maintain ink solubility, allowing one additive to address multiple aspects of debris management and simplifying the overall ink formulation
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 reduces debris at nozzle ejection sites, enhancing inkjet printing by minimizing blockages and maintaining print quality, as evidenced by fewer blank line bands in printed areas compared to compositions without polymeric dispersants.
Implementation Method 1
The hydrophobic segment of the polymeric dispersant adsorbs to a surface of a debris particle within the ink composition
Implementation Method 2
The hydrophilic segment of the polymeric dispersant extends into the aqueous medium and provides steric stabilization
Implementation Method 3
at least one surfactant in an amount between and including 0.5% by weight and 1.5% by weight
Data Source
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AI summary
An ink composition is disclosed that includes: at least one color dye in an amount between and including 1% by weight and 7% by weight; at least one polymeric dispersant in an amount between and including 0.1% by weight and 1% by weight; at least one organic solvent in an amount between and including 18% by weight and 22% by weight; at least one surfactant in an amount between and including 0.5% by weight and 1.5% by weight; at least one buffer in an amount between and including 0.1% by weight and 0.5% by weight; at least one biocide in an amount between and including 0.05% by weight and 0.2% by weight; and the balance being deionized water.