Ink Set with Filling Liquid for Recording Head Discharge Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet recording heads face discharge failures due to residual inkjet ink remaining in the ink flow channel, which causes pigment agglomeration during transportation and storage, leading to clogging and operational issues.
Innovation Solution
An ink set comprising inkjet ink with a pigment, pigment coating resin, and a first alkali metal ion, combined with a recording head filling liquid containing polyethylene glycol, a second alkali metal ion, and a surfactant, which facilitates the introduction of the filling liquid into the recording head and inhibits pigment agglomeration by maintaining dispersibility and solubility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the recording head is filled with inkjet ink for discharge testing, then discharge performance can be evaluated, but residual ink remains in the ink flow channel causing pigment agglomeration and discharge failure
Solution Approach 1:
The patent applies preliminary action by filling the recording head with a filling liquid containing dispersant and surfactant immediately after discharge testing. This preliminary treatment prevents pigment agglomeration before the recording head is stored or shipped, addressing the harmful effect of residual ink before it can cause discharge failure.
Solution Approach 2:
The filling liquid acts as an intermediary substance between the residual inkjet ink and the environment during storage/transport. The dispersant and surfactant in the filling liquid mediate the interaction with residual pigment particles, preventing agglomeration while the recording head is inactive.
2Object-generated harmful factors
If the recording head is washed to remove residual ink, then pigment agglomeration is reduced, but the ink flow channel is very minute making complete removal difficult
Solution Approach 1:
The filling liquid serves as an intermediary that chemically interacts with residual ink particles through dispersants and surfactants. This chemical mediation makes removal easier compared to mechanical washing alone, as the filling liquid penetrates the minute ink flow channels and keeps pigment particles dispersed.
Solution Approach 2:
The patent changes the chemical parameters of the liquid environment by introducing a filling liquid with specific dispersant and surfactant concentrations. This parameter change from plain water to a chemically active filling liquid enhances the ability to remove and prevent agglomeration of residual pigment in the minute ink flow channels.
3Object-generated harmful factors
If a recording head filling liquid containing silicone oil is used, then pigment agglomeration is inhibited, but the liquid must be easily introduced into the ink flow channel
Solution Approach 1:
The patent optimizes the physical and chemical parameters of the filling liquid, including viscosity, surface tension, and composition ratios of dispersant and surfactant. These parameter changes ensure the filling liquid has appropriate flow characteristics for easy introduction into minute ink flow channels while maintaining its pigment-dispersing function.
Solution Approach 2:
The filling liquid is a composite material containing water, dispersant, surfactant, and optionally silicone oil. This composite formulation combines the benefits of multiple components: water as base, dispersant for pigment stabilization, surfactant for surface tension reduction (aiding introduction), and silicone oil for additional anti-agglomeration properties.
Data Source
AI summary
An ink set includes an inkjet ink and a recording head filling liquid. The inkjet ink includes a pigment, a pigment coating resin, a first alkali metal ion, and water. The recording head filling liquid includes polyethylene glycol, a second alkali metal ion, a surfactant, and water. The polyethylene glycol has a mass average molecular weight of at least 180 and no greater than 800. A content ratio of the surfactant in the recording head filling liquid is greater than 0.00% by mass and no greater than 0.10% by mass. The first and second alkali metal ions each contain at least one of Li+, Na+, and K+.