Thermally Switchable Transfix Blanket for Indirect Printing

Solution Overview

Problem

Intermediate transfer members in indirect printing methods face a challenge in simultaneously achieving good wetting and efficient transfer of aqueous ink, as existing materials either fail to wet the ink due to low surface tension or impede transfer due to high surface tension.

Innovation Solution

A polymer composition with a base polymer matrix and a grafted stimulus-responsive polymer layer, whose surface free energy is reversibly adjustable from a higher to a lower state upon heating, enabling both effective wetting and transfer by switching surface energy in response to temperature changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a material with low surface tension is used to form the intermediate transfer member, then wetting of aqueous ink is improved, but transfer of the transient image to substrate is impeded

Engineering Contradiction:

Improvewetting of inkVSAvoidtransfer efficiency

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The intermediate transfer member's surface free energy is made dynamically adjustable through thermal switching. The stimulus-responsive polymer layer changes its surface free energy state in response to temperature changes, allowing the material to transition from a high surface energy state (for ink wetting) to a low surface energy state (for image transfer), thereby resolving the contradiction between wetting and transfer efficiency

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the surface free energy parameter of the intermediate transfer member by controlling the temperature of the stimulus-responsive polymer layer. By adjusting the temperature relative to the critical activation temperature, the surface free energy switches between high and low states, enabling the material to optimize both wetting and transfer properties at different process stages

Inventive Principle:

Principle #35Parameter changes

2Productivity

If a material with high surface tension is used to form the intermediate transfer member, then transfer of transient image is improved, but wetting of aqueous ink is impeded

Engineering Contradiction:

Improvetransfer efficiencyVSAvoidwetting of ink

Core Design Contradiction:

ProductivityVSEase of manufacture

Solution Approach 1:

The intermediate transfer member's surface free energy is made dynamically adjustable through thermal switching. The stimulus-responsive polymer layer changes its surface free energy state in response to temperature changes, allowing the material to transition from a high surface energy state (for ink wetting) to a low surface energy state (for image transfer), thereby resolving the contradiction between wetting and transfer efficiency

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the surface free energy parameter of the intermediate transfer member by controlling the temperature of the stimulus-responsive polymer layer. By adjusting the temperature relative to the critical activation temperature, the surface free energy switches between high and low states, enabling the material to optimize both wetting and transfer properties at different process stages

Inventive Principle:

Principle #35Parameter changes

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 solution allows for improved ink spreading and transfer, resulting in enhanced image quality by optimizing both wetting and transfer properties of the intermediate transfer member.

Implementation Method 1

the surface free energy of the stimulus-responsive polymer is reversibly adjustable from a first surface free energy state to a second surface free energy state when heated to a predetermined critical activation temperature

Methodology Applied

Scientific EffectThermal switching of surface free energy: Thermochromism

Data Source

PatentUS8696106B1Thermally switchable transfix blanket made with grafted switchable polymer for indirect printing methods

Publication Date: 2014.04.15 XEROX CORP

AI summary

A polymer composition includes a first polymer layer containing a base polymer matrix, and a second polymer layer grafted onto the first layer. The second polymer layer contains a stimulus-responsive polymer, and the surface free energy of the stimulus-responsive polymer is adjustable from a first surface free energy state to a second surface free energy state when heated to a critical activation temperature. A method of preparing a polymer composition includes providing a first polymer layer containing a base polymer, and grafting a second polymer layer containing a stimulus-responsive layer onto the first layer. A method of printing an image involves applying an ink onto an intermediate transfer member containing a first polymer layer containing a base polymer matrix and a second polymer layer containing a stimulus-responsive polymer grafted onto the first layer, spreading the ink, inducing a property change of the ink, and transferring the ink to a substrate.