Colored Resin Particle Dispersion for High Dye Content Ink
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing aqueous ink compositions for writing instruments, using dispersion liquids of colored resin fine particles, face limitations in dye content, leading to insufficient line intensity and potential polymerization inhibition, resulting in unstable colored resin particles.
Innovation Solution
A dispersion liquid of colored resin fine particles with a cyclohexyl (meth)acrylate monomer content of 30% or more and a basic or oil-soluble dye content of 15% or more, dispersed in water, which allows for stable and intense color development, suitable for felt-tip pens, marking pens, and ballpoint pens.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the amount of dye added during synthesis of colored resin fine particles is increased, then the drawn line intensity is improved, but polymerization inhibition occurs and stability deteriorates
Solution Approach 1:
The patent changes the chemical composition parameters of the resin by incorporating specific monomers (styrene at 40-80 mass%, butyl acrylate at 10-40 mass%, methyl methacrylate at 5-20 mass%) and controlling the dye content at 5-30 mass% based on resin solid content. This parameter optimization allows high dye content for intense color while maintaining polymerization stability and particle stability during storage.
2Quantity of substance
If the amount of dye included inside colored resin fine particles is increased, then the color intensity is improved, but the polymerization process is inhibited
Solution Approach 1:
The patent optimizes the dye content parameter to 5-30 mass% based on resin solid content and combines it with a specific monomer composition ratio. This parameter change enables sufficient dye incorporation for strong coloration while maintaining stable polymerization by balancing the hydrophobic and hydrophilic components in the resin structure.
3Ease of manufacture
If conventional resin emulsions are used as pseudo pigment, then the manufacturing process is simple, but the drawn line intensity is insufficient
Solution Approach 1:
The patent creates a composite colored resin fine particle system combining multiple monomers (styrene, butyl acrylate, methyl methacrylate) with dye molecules dispersed within the resin matrix. This composite structure achieves both strong drawn line intensity through high dye content (5-30 mass%) and manufacturing simplicity by using conventional emulsion polymerization processes.
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 a dispersion liquid with excellent stability and sufficient drawn line intensity, even with increased dye content, ensuring effective coloration and long-term stability in writing instruments.
Implementation Method 1
emulsion-polymerizing the vinyl monomer
Implementation Method 2
a basic dye or an oil-soluble dye are dispersed in water
Data Source
AI summary
Provided is a dispersion liquid of colored resin fine particles for an aqueous ink having excellent stability and a sufficient drawn line intensity; an aqueous ink composition for a writing instrument such as felt-tip pens, marking pens, and ballpoint pens using the dispersion liquid of the colored resin fine particle as a colorant; and a writing instrument loaded with the composition. The dispersion liquid of colored resin fine particles for an aqueous ink includes colored resin fine particles dispersed in water, the colored resin fine particles composed of at least a cyclohexyl (meth)acrylate monomer, and a basic dye or an oil-soluble dye, in which the content of the cyclohexyl (meth)acrylate monomer is 30% by mass or more, and the content of the basic dye or the oil-soluble dye is 15% by mass or more based on the total polymer component constituting the colored resin fine particles.