Aqueous Ink-Jet Ink Viscosity Control for High-Speed Printing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-speed printing on nonabsorbable media using aqueous inks often results in image quality degradation due to spotting and bleeding, as existing methods inadequately increase ink viscosity, leading to suboptimal image quality.
Innovation Solution
An aqueous ink-jet ink containing water, a pigment, an organic or inorganic acid, and an amine with a resin having a higher pKa than the acid, which is heated to accelerate pH decrease, reducing solubility and dispersibility of the resin and pigment, promoting deposition and aggregation, thereby increasing viscosity and reducing bleed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If aqueous ink is used for high-speed printing on nonabsorbable media, then printing speed is improved, but image quality deteriorates due to spotting and bleeding
Solution Approach 1:
The invention changes the chemical parameters of the ink by incorporating a resin with higher pKa than the acid component, which alters the pH characteristics and interaction mechanisms of the ink components, enabling rapid viscosity increase that prevents bleeding while maintaining high-speed printing capability
Solution Approach 2:
The invention uses a composite system combining specific resin (with higher pKa than acid), acid component, and optional amine components to create an ink formulation that achieves both high-speed printing and bleed prevention through synergistic interactions among the components
2Manufacturing precision
If ink viscosity is increased to prevent bleeding, then image quality is improved, but printing speed decreases
Solution Approach 1:
The invention creates a dynamic viscosity system where the ink maintains lower viscosity during ejection for high-speed printing, then rapidly increases viscosity after deposition to prevent bleeding, achieving both high productivity and manufacturing precision through time-dependent viscosity control
3Object-generated harmful factors
If resin and pigment aggregation is promoted to increase viscosity, then bleed is reduced, but ink stability deteriorates
Solution Approach 1:
The invention carefully controls the pH parameter by selecting resin with higher pKa than the acid component, creating a buffered system that promotes controlled aggregation to increase viscosity and reduce bleed while maintaining sufficient ink stability for practical use
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 method effectively prevents bleed and achieves highly detailed image quality during high-speed printing by enhancing the interaction between resin and pigment, resulting in improved ink viscosity and image quality.
Implementation Method 1
drying accelerates water evaporation, whereby the ratio of a glycol ether or 1,2-alkanediol component in a deposited ink is increased and then the interaction of each water-soluble resin is enhanced, resulting in an increase in ink viscosity
Implementation Method 2
utilizes a pH decrease via volatilization of an ammonium salt
Data Source
AI summary
Provided are an aqueous ink-jet ink and a method for forming an ink-jet image enabling to decrease bleed occurrence during high-speed printing and to realize highly detailed image quality. An aqueous ink-jet ink characterized by containing water, a pigment, an organic or inorganic amine salt, and a water-soluble resin having a higher pKa than an acid component formed by dissociation of the amine salt in an ink.