Alcohol Soluble Ink Binder Composition for Pigment Dispersion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Alcohol-soluble inks face challenges with pigment dispersion and anti-blocking due to the limitations of commonly used binders like TPU and TPA, which are optimized for adhesion or bonding, resulting in lower gloss, color strength, higher viscosity, and settling issues, and are not compatible with alcohol/water solvent systems.
Innovation Solution
An alcohol-soluble printing ink composition that includes a binder comprising polyurethane and a cellulose ester such as cellulose acetate propionate (CAP) or cellulose acetate butyrate (CAB) with specific hydroxyl and acetyl group content, combined with an alcohol-water solvent system, enhancing pigment dispersibility and anti-blocking performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If commonly used binders such as TPU and TPA are used in alcohol soluble inks, then adhesion and bonding performance are improved, but pigment dispersion and anti-blocking performance deteriorate
Solution Approach 1:
The patent uses a composite binder system combining TPU or TPA with cellulose ester (CAP or CAB) in specific ratios. The cellulose ester component provides excellent pigment dispersion and anti-blocking properties while the TPU/TPA provides adhesion and bonding, creating a synergistic effect that resolves the contradiction between adhesion and pigment dispersion performance.
2Strength
If commonly used binders such as TPU and TPA are used in alcohol soluble inks, then adhesion and bonding performance are improved, but gloss and color strength deteriorate
Solution Approach 1:
The composite binder system of TPU/TPA combined with cellulose ester in optimized ratios maintains the bonding strength provided by TPU/TPA while the cellulose ester component enhances gloss and color strength, resolving the contradiction between bonding performance and optical properties.
3Strength
If commonly used binders such as TPU and TPA are used in alcohol soluble inks, then adhesion performance is improved, but viscosity increases
Solution Approach 1:
The patent optimizes the molecular weight parameters of the cellulose ester component (Mn: 7,000-13,000 g/mol) and controls the binder ratio to achieve the desired balance between adhesion and viscosity. By adjusting these physical parameters, the ink achieves lower viscosity while maintaining adhesion performance.
4Stability of the object's composition
If high molecular weight cellulose ester is used to improve pigment dispersing and anti-blocking performance, then dispersibility is improved, but compatibility with alcohol/water solvent blends deteriorates
Solution Approach 1:
The patent specifies a number-average molecular weight (Mn) range of 7,000 to 13,000 g/mol for the cellulose ester, which is lower than conventional high molecular weight cellulose ester. This parameter optimization enables the cellulose ester to be compatible with alcohol/water solvent blends while maintaining excellent pigment dispersing and anti-blocking performance.
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 composition achieves superior adhesion, anti-blocking, and dispersability, ensuring excellent pigment dispersibility for both organic and inorganic pigments, while maintaining compatibility with alcohol-based solvent systems, thus improving printing quality and efficiency.
Implementation Method 1
an alcohol-soluble printing ink composition... a solvent system comprising at least 50% by weight of an alcohol... and a cellulose ester
Data Source
Figure 1
Figure 2
AI summary
Disclosed herein are ink formulations that result in improved pigment dispersion and anti-blocking in alcohol soluble inks. The ink compositions include at least one colorant; a binder comprising polyurethane; a solvent system comprising at least about 50% by weight of an alcohol, based on the total weight of the solvent system; and a cellulose ester selected from cellulose acetate propionate and cellulose acetate butyrate.