Supercritical Fluid Extraction for Electrostatic Ink Concentration

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Solution Overview

Problem

Existing methods for concentrating electrostatic ink compositions often lead to particle agglomeration, charge loss, and high energy consumption, which can affect the quality and efficiency of the ink in electrostatic printing processes.

Innovation Solution

The method involves using supercritical fluid extraction to remove the liquid carrier from the initial ink composition, resulting in a concentrated composition that can be stored and later rediluted with a second liquid carrier, maintaining particle size and charge integrity while reducing energy requirements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If existing concentration methods are used on electrostatic ink compositions, then the ink can be concentrated for storage and transport, but particle agglomeration occurs and charge is lost

Engineering Contradiction:

Improveink concentrationVSAvoidparticle charge integrity

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent changes the physical state of the extraction medium from liquid to supercritical fluid, and controls pressure and temperature parameters during extraction and drying to prevent particle agglomeration and charge loss while achieving concentration

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent utilizes the phase transition of carbon dioxide between supercritical and gaseous states to achieve extraction and subsequent removal of the extraction medium, leaving concentrated ink particles without agglomeration or charge loss

Inventive Principle:

Principle #36Phase transitions

2Quantity of substance

If existing concentration methods are used on electrostatic ink compositions, then concentration can be achieved, but energy consumption is high

Engineering Contradiction:

Improveink concentrationVSAvoidprocessing energy

Core Design Contradiction:

Quantity of substanceVSUse of energy by moving object

Solution Approach 1:

The patent exploits the phase transition of supercritical carbon dioxide to gas upon pressure release, which occurs naturally without requiring additional energy input for evaporation, thereby significantly reducing energy consumption compared to thermal evaporation methods

Inventive Principle:

Principle #36Phase transitions

Solution Approach 2:

The patent replaces thermal energy-based concentration methods with a pressure-controlled supercritical fluid extraction system, substituting thermal processes with mechanical pressure control to achieve concentration with lower energy input

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Quantity of substance

If liquid carrier is removed from ink composition, then concentrated composition is obtained for storage, but particle size may change

Engineering Contradiction:

Improveink concentrationVSAvoidparticle size consistency

Core Design Contradiction:

Quantity of substanceVSManufacturing precision

Solution Approach 1:

The patent carefully controls pressure and temperature parameters during supercritical extraction and drying processes to prevent particle agglomeration and maintain consistent particle size in the concentrated composition

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses supercritical carbon dioxide as an intermediary extraction medium that can penetrate the ink composition and remove liquid carrier without directly contacting and potentially aggregating the ink particles, thus preserving particle size consistency

Inventive Principle:

Principle #24Intermediary (Mediator)

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

This approach allows for efficient concentration and redilution of electrostatic ink compositions without significant particle size or charge effects, enabling low-energy processing and maintaining ink performance in electrostatic printing processes.

Implementation Method 1

removing at least some of the liquid carrier from the initial liquid electrostatic ink composition using supercritical fluid extraction to provide a concentrated composition comprising the chargeable toner particles

Methodology Applied

Scientific EffectSupercritical fluid extraction: Supercritical Fluid Extraction

Data Source

PatentEP3094693B1Concentrating an ink composition

Publication Date: 2019.06.12 HP INDIGO BV

AI summary

Herein is disclosed a method for processing a liquid electrostatic ink composition, the method comprising: providing an initial liquid electrostatic ink composition comprising chargeable toner particles dispersed in a first liquid carrier, removing at least some of the liquid carrier from the initial liquid electrostatic ink composition using supercritical fluid extraction to provide a concentrated composition comprising the chargeable toner particles, adding a second liquid carrier to the concentrated composition to form a final liquid electrostatic ink composition. Also disclosed herein is a liquid electrostatic ink composition producible according to the method.