Latex Particulates with Intermingled Polymer Strands for Ink-Jet Inks

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Aqueous ink-jet inks face challenges with latex particulates regarding stability and durability under thermal shear conditions and storage, affecting nozzle reliability and print quality on various media types.

Innovation Solution

Incorporating intermingled low Tg and high Tg polymer strands in latex particulates, mimicking polyurethane structures, with minimal wax emulsions to enhance scratch resistance and stability, allowing for superior print durability and gloss retention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If conventional latex particulates are used to improve print durability, then scratch resistance and adhesion are enhanced, but nozzle reliability deteriorates due to thermal shear damage in thermal ink-jet print heads

Engineering Contradiction:
Improvescratch resistanceVSAvoidnozzle reliability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent changes the chemical composition parameters of the latex particulates by incorporating specific functional groups (carboxylic acid, hydroxyl, amine) and controlling molecular weight (5,000-500,000) and glass transition temperature ranges. These parameter modifications enable the latex to withstand thermal shear conditions in thermal ink-jet print heads while maintaining scratch resistance and adhesion properties.

Inventive Principle:
Principle #35Parameter changes

2Strength

If latex particulates are incorporated to enhance print durability, then adhesion and scratch resistance improve, but storage stability deteriorates due to particulate settling over time

Engineering Contradiction:
ImproveadhesionVSAvoidstorage stability
Core Design Contradiction:
StrengthVSStability of the object's composition

Solution Approach 1:

The patent modifies the latex particulate parameters including molecular weight (5,000-500,000), glass transition temperature (below -50°C, -50°C to 50°C, or above 50°C), and functional group content (0.1-10 mmol/g carboxylic acid, 0.1-10 mmol/g hydroxyl, or 0.1-5 mmol/g amine). These changes optimize the balance between adhesion performance and storage stability by preventing particulate settling while maintaining bonding strength to substrates.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates composite latex particulates with multiple functional groups and controlled molecular architectures that combine the benefits of strong adhesion with improved colloidal stability. The composite structure includes specific ratios of hydrophobic and hydrophilic segments, along with crosslinkable functional groups, which work together to prevent settling while maintaining attachment strength.

Inventive Principle:
Principle #40Composite materials

3Strength

If polyurethane latex is used to achieve excellent scratch resistance, then durability is improved, but compatibility with aqueous ink-jet systems deteriorates

Engineering Contradiction:
Improvescratch resistanceVSAvoidink system compatibility
Core Design Contradiction:
StrengthVSAdaptability or versatility

Solution Approach 1:

The patent copies the desirable scratch resistance properties of polyurethane latex but achieves them through alternative polymer compositions that are compatible with aqueous ink-jet systems. Instead of using traditional polyurethane chemistry, the patent employs acrylic, vinyl, or other water-compatible polymer backbones with incorporated crosslinkable functional groups, replicating the performance characteristics without the ink system incompatibility.

Inventive Principle:
Principle #26Copying

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 improved scratch resistance, stability, and print quality by maintaining intermingled polymer strands' structure, even under varying conditions, and is compatible with a wide range of substrates and printing architectures.

Implementation Method 1

Incorporating intermingled low Tg and high Tg polymer strands in latex particulates, mimicking polyurethane structures

Methodology Applied
Scientific EffectGlass transition temperature (Tg) differentiation:

Implementation Method 2

a latex component of the ink can form a film on a media surface, entrapping and protecting the colorant within the hydrophobic print film

Methodology Applied
Scientific EffectHydrophobic effect: Hydrophobe

Implementation Method 3

latex particulates can improve durability of prints, they undergo severe thermal shear conditions when printed through thermal ink-jet print heads

Methodology Applied
Scientific EffectThermal shear:

Data Source

PatentUS9732244B2Latexes and associated ink-jet inks
Publication Date: 2017.08.15 HEWLETT PACKARD DEVELOPMENT COMPANY LP

AI summary

The present disclosure provides ink-jet inks and associated methods. In one example, an ink jet ink can comprise an ink vehicle, a wax emulsion, and a latex particulate. The latex particulate can comprise multiple intermingled discrete polymer strands, including: a low Tg polymer strand having a Tg below 50° C. and a high Tg polymer strand having a Tg at 50° C. or above. Additionally, the Tg of the high Tg polymer strand can be at least 50° C. greater than the Tg of the low Tg polymer strand.