Thermosensitive Recording Medium Hand Cream Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Thermosensitive recording media face issues with hand cream adhesion leading to image degradation due to lack of effective resistance, despite the use of hydrazine self-cross-linking acrylic-based resins for hand cream resistance.

Innovation Solution

Incorporating a thermosensitive recording layer with 4-hydroxy-4'-benzyloxydiphenylsulfone and a diphenylsulfone compound, where the diphenylsulfone content is less than 3.0 parts by mass relative to 1.0 part of 4-hydroxy-4'-benzyloxydiphenylsulfone, enhancing hand cream resistance and image density.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If hand creams are applied to hands that touch thermosensitive recording media, then the surfaces are protected, but hand creams adhere to the recording layer causing image degradation

Engineering Contradiction:

Improvehand cream adhesionVSAvoidimage quality

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent converts the harmful effect of hand cream adhesion into a beneficial resistance mechanism by formulating the recording layer with specific resin compositions (acrylic-based resins with carboxyl groups) that chemically interact with hand cream components. This formulation makes the recording layer inherently resistant to hand cream adhesion, thereby protecting image quality while allowing normal hand contact.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Reliability

If conventional thermosensitive recording media are used, then basic recording function is achieved, but hand cream resistance is insufficient leading to image fading

Engineering Contradiction:

Improvehand cream resistanceVSAvoidimage degradation

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the chemical parameters of the recording layer by specifying particular resin compositions (acrylic-based resins with carboxyl groups in amounts of 5-50 mass%). This parameter change fundamentally alters the interaction between the recording layer and hand creams, providing superior hand cream resistance and preventing image degradation while maintaining recording functionality.

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If the content of diphenylsulfone compound is increased to improve color developing sensitivity, then image density improves, but hand cream resistance deteriorates

Engineering Contradiction:

Improvecolor developing sensitivityVSAvoidhand cream resistance

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent optimizes the concentration parameters of multiple components simultaneously: diphenylsulfone compound (0.1-10 mass%), 4-hydroxy-4'-benzyloxydiphenylsulfone (1-20 mass%), and acrylic-based resins with carboxyl groups (5-50 mass%). This multi-parameter optimization achieves the breakthrough of providing both high color developing sensitivity and excellent hand cream resistance, resolving the previous trade-off between these properties.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite material system combining diphenylsulfone compounds, 4-hydroxy-4'-benzyloxydiphenylsulfone, and acrylic-based resins with carboxyl groups. This composite formulation synergistically provides both high color developing sensitivity from the sulfone compounds and excellent hand cream resistance from the carboxyl-containing resins, eliminating the need to choose between these properties.

Inventive Principle:

Principle #40Composite materials

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 thermosensitive recording medium with high color developing sensitivity, high image density, and excellent hand cream resistance, effectively preventing image degradation from hand cream adhesion.

Implementation Method 1

a thermosensitive recording layer provided over at least one surface of the support and containing a leuco dye, a first developer, and a second developer

Methodology Applied

Scientific EffectThermosensitive color development reaction: Chemical Bonding

Implementation Method 2

it has been found that when a thermosensitive recording layer contains a cross-linking agent and a binder resin, and is subjected to a heat treatment, cross-linked structures are formed in the thermosensitive recording layer, whereby hand creams used for hand protection can be prevented from adhering to image portions

Methodology Applied

Scientific EffectCross-linking: Chemical Bonding

Data Source

PatentEP3475095B1Thermosensitive recording medium and article

Publication Date: 2020.01.22 RICOH CO LTD

AI summary

Provided is a thermosensitive recording medium including a support, and a thermosensitive recording layer provided over at least one surface of the support and containing a leuco dye and a developer, wherein the developer includes 4-hydroxy-4'-benzyloxydiphenylsulfone and a diphenylsulfone compound represented by general formula (1), and wherein a content of the diphenylsulfone compound represented by general formula (1) is less than 3.0 parts by mass relative to 1.0 part by mass of the 4-hydroxy-4'-benzyloxydiphenylsulfone.