Inkjet Nozzle Stability via TiO2 Particle Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet printing methods face challenges with long-term discharging stability, particularly with single-pass printing, as pigments in white inks tend to settle in nozzles, leading to printing failures due to the high pigment specific gravity of white pigments.
Innovation Solution
A liquid discharging apparatus and method using an ink composition containing water, an organic solvent, at least two kinds of urethane resins, and titanium oxide, with a titanium oxide content of 20-30% by mass and a volume average particle diameter of 300-630 nm, which is circulated through a liquid discharging head with a nozzle, enhancing discharging stability and hiding power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If white ink with high pigment specific gravity is used for single-pass printing, then printing speed is improved, but pigment settles in nozzles causing discharging failure
Solution Approach 1:
The patent changes the particle size parameter of titanium oxide from conventional larger sizes to specifically 300-630 nm range, and adjusts pigment content to 20-30% by mass. These parameter modifications prevent sedimentation while maintaining high hiding power, enabling stable single-pass printing with white ink
Solution Approach 2:
The patent uses a composite ink formulation combining titanium oxide pigment with specific resin components and solvents. This composite structure ensures uniform dispersion and prevents pigment settling, resolving the contradiction between high productivity and discharging reliability
2Illumination intensity
If titanium oxide content is increased to improve hiding power, then image quality is improved, but ink viscosity increases affecting discharging
Solution Approach 1:
The patent optimizes titanium oxide particle size to 300-630 nm and content to 20-30% by mass. This parameter combination achieves high hiding power while controlling viscosity by reducing inter-particle aggregation, allowing smooth ink discharge
Solution Approach 2:
The patent introduces specific resin components and surfactants as intermediaries between titanium oxide particles and the continuous phase. These intermediaries improve dispersion and reduce viscosity, enabling high pigment content without compromising flowability
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 provides high printing stability and excellent hiding power even with single-pass printing methods by preventing titanium oxide settling and maintaining uniform dispersion, ensuring consistent ink flow and image quality.
Implementation Method 1
white inks using white pigments have a high pigment specific gravity. Therefore, if printing apparatuses are suspended for a long period, the pigments settle in the nozzles
Implementation Method 2
an individual liquid chamber having a circulation flow path through which the ink is circulated
Data Source
AI summary
Provided is a liquid discharging apparatus including: a storage storing an ink containing water, an organic solvent, at least two kinds of urethane resins, and titanium oxide; and a liquid discharging head. The liquid discharging head includes an individual liquid chamber having a circulation flow path through which the ink is circulated. The liquid discharging head has a nozzle communicating with the individual liquid chamber and through which a liquid droplet of the ink is discharged. The content of the titanium oxide in the ink is 20% by mass or greater but 30% by mass or less. The volume average particle diameter of the titanium oxide is 300 nm or greater but 630 nm or less.