Water-based Ink Formulation for Jetting Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Water-based inks for inkjet recording face challenges in suppressing viscosity increase and solidification due to drying, with existing humectants like glycerol and diethylene glycol providing insufficient effects, affecting short-term and long-term jetting stability and re-dispersion properties.
Innovation Solution
A water-based ink formulation incorporating a self-dispersible pigment modified by a carboxylic acid group, glycerol, diethylene glycol, and alkylene glycol monoalkyl ether, with specific blending ratios to optimize viscosity control and re-dispersion properties, ensuring stable ink discharge after short-term and long-term drying.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If diethylene glycol is used as humectant, then viscosity is low and jetting stability is improved, but volatility is high causing insufficient viscosity-increase suppressing effect after drying
Solution Approach 1:
The patent combines diethylene glycol (low viscosity) with glycerol (low volatility) in a specific ratio (0.24≦DEG/(Gly+DEG)≦0.92) to create a humectant system that achieves both low viscosity for good jetting stability and low volatility for sustained viscosity control after drying, resolving the contradiction between immediate and long-term performance
Solution Approach 2:
The patent optimizes the compositional parameters of the humectant system by controlling the weight ratio of diethylene glycol to glycerol within a specific range, and by adjusting the total humectant content (5-50 wt%), to achieve the optimal balance between viscosity and volatility characteristics for both short-term and long-term jetting stability
2Reliability
If glycerol is used as humectant, then volatility is low and solidification is suppressed, but viscosity is relatively high reducing viscosity-increase suppressing effect
Solution Approach 1:
The patent merges glycerol (low volatility, high viscosity) with diethylene glycol (high volatility, low viscosity) in a controlled ratio to create a synergistic humectant system that achieves both solidification suppression from glycerol and low viscosity from diethylene glycol, while the specific ratio ensures optimal viscosity-increase suppression after drying
3Duration of action of moving object
If water-based ink is left unused for short period, then drying occurs causing viscosity increase, but jetting stability must be maintained
Solution Approach 1:
The patent uses a specifically formulated humectant system acting as an intermediary substance that regulates water activity and prevents excessive drying during short-term storage, thereby maintaining viscosity within acceptable ranges for jetting stability without requiring external intervention
Solution Approach 2:
The patent adjusts the total humectant content parameter (5-50 wt%) and the compositional ratio parameter (0.24≦DEG/(Gly+DEG)≦0.92) to control the drying rate and viscosity development during short-term storage, achieving optimal jetting stability after brief idle periods
4Duration of action of stationary object
If water-based ink is left unused for long period, then drying and solidification occur affecting re-dispersion property, but jetting stability must be maintained
Solution Approach 1:
The patent employs the humectant system (diethylene glycol + glycerol) as a long-term protective intermediary that prevents complete drying and solidification during extended storage, maintaining the ink in a state that allows effective re-dispersion and restores jetting stability after long idle periods
Solution Approach 2:
The patent combines the low volatility characteristic of glycerol with the low viscosity characteristic of diethylene glycol in a specific ratio, creating a humectant system that provides both long-term solidification prevention and maintains re-dispersion capability, achieving superior long-term storage stability
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 formulation effectively suppresses viscosity increase after drying, enhancing both short-term and long-term jetting stability and re-dispersion properties, allowing for stable ink discharge and improved imaging quality.
Implementation Method 1
self-dispersible pigment modified by carboxylic acid group
Implementation Method 2
self-dispersible pigment modified by carboxylic acid group
Implementation Method 3
glycerol and diethylene glycol satisfy the following condition
Implementation Method 4
humectant (antidrying agent) is generally used in the water-based ink
Implementation Method 5
alkylene glycol monoalkyl ether
Implementation Method 6
alkylene glycol monoalkyl ether
Data Source
AI summary
There is provided a water-based ink for inkjet recording, including: a self-dispersible pigment modified by carboxylic acid group; glycerol; diethylene glycol; alkylene glycol monoalkyl ether; and water, wherein the glycerol and the diethylene glycol satisfy the following condition (i):0.24≦DEG/(Gly+DEG)≦0.92 (i)in the condition (i), Gly represents an amount of the glycerol in the water-based ink (% by weight); and DEG represents an amount of the diethylene glycol in the water-based ink (% by weight).