Ink Set Dynamic Surface Tension Control for Printing Graininess
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ink-jet recording methods face challenges with graininess in low density printed parts, limited color reproduction range, blurring, and color unevenness, particularly when using traditional three-color or four-color ink sets composed of yellow, magenta, cyan, and black inks, which affect the vividness and sharpness of printed images, especially in blue and green color development.
Innovation Solution
A water-based ink set is developed that includes cyan and blue or cyan and green inks, with controlled dynamic surface tensions at specific lifetimes to reduce graininess, extend color reproduction range, prevent blurring, and minimize color unevenness, by adjusting the dynamic surface tensions of these inks to satisfy specific inequalities, ensuring optimal ink penetrability and spreading characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the penetrability of color ink is lowered to reduce blurring, then blurring is reduced, but color unevenness occurs due to non-uniform ink penetration
Solution Approach 1:
The patent applies parameter changes by adjusting the dynamic surface tension of inks at different time points (initial vs. final penetration stages). The ink composition is modified to have high initial penetrability (low initial surface tension) for uniform absorption, then reduced penetrability (high final surface tension) to prevent blurring. This temporal parameter change resolves the contradiction between reducing blurring and preventing color unevenness.
2Manufacturing precision
If the penetrability of color ink is increased to improve color unevenness, then color unevenness is improved, but blurring occurs in color text printing
Solution Approach 1:
The patent uses parameter changes by controlling the dynamic surface tension to vary over time. Initially, low surface tension allows high penetrability for uniform ink distribution across the paper surface. As penetration progresses, surface tension increases to reduce further penetration, preventing blurring. This temporal evolution of parameters simultaneously achieves both improved color uniformity and reduced blurring.
3Manufacturing precision
If dot density is decreased in low density printed part, then graininess is reduced, but individual dots become discernable causing image to be grainy
Solution Approach 1:
The patent applies parameter changes to ink surface tension to control penetration dynamics. By optimizing the balance between initial penetrability and final retention, the ink forms smoother transitions between dots while maintaining adequate dot density. The dynamic surface tension control allows ink to spread sufficiently to reduce graininess but not so much that dots merge or become indistinct.
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 set effectively reduces graininess in low density printed parts, enhances color reproduction, prevents blurring, and ensures color evenness, particularly in blue and green color printing, while maintaining high density color reproduction, thereby improving the overall printing quality and vividness of images.
Implementation Method 1
the dynamic surface tensions of the cyan and blue inks as determined by a maximum bubble pressure method at a measurement temperature of 25° C. satisfy the following inequalities
Data Source
AI summary
The water-based ink set for ink-jet recording includes a cyan ink and a blue ink with dynamic surface tensions thereof satisfying the following inequalities (ICB), (IICB), (IIICB) and (IVCB)σ30C≦about 49 mN/m (ICB)σ30C+σ30B≦about 100 mN/m (IICB)wherein σ30C is the dynamic surface tension of the cyan ink at a lifetime of 30 ms and σ30B is the dynamic surface tension of the blue ink at a lifetime of 30 ms,σ1000B≧about 36 mN/m (IIICB)σ1000C+σ1000B≧about 70 mN/m (IVCB)wherein σ1000C is the dynamic surface tension of the cyan ink at a lifetime of 1,000 ms and σ1000B is the dynamic surface tension of the blue ink at a lifetime of 1,000 ms.