Cellulose Fiber Resin Laminate Adhesion via Intermediary Layer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional laminates with ultrafine cellulose fiber-containing sheets and resin layers exhibit insufficient adhesion properties, limiting their practical applications.

Innovation Solution

A laminate configuration featuring a fiber layer with cellulose fibers of 1000 nm or less and a resin layer containing an adhesion aid, such as an isocyanate compound or organic silicon compound, which is uniformly dispersed or concentrated near the fiber layer, enhancing the adhesion between the two layers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional ultrafine cellulose fiber-containing sheets are laminated with resin layers without adhesion aids, then the laminate structure is simple and manufacturing is easy, but the adhesion properties between the fiber layer and resin layer are insufficient

Engineering Contradiction:
Improveadhesion propertiesVSAvoidlaminate structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

An adhesion aid layer comprising silane-modified polyethyleneoxide is introduced between the ultrafine cellulose fiber-containing sheet and the resin layer. This intermediary layer acts as a bridge that chemically bonds to both the cellulose fibers and the resin, significantly improving adhesion properties while maintaining a relatively simple laminate structure with only three layers.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention uses a composite adhesion aid system combining silane-modified polyethyleneoxide with specific resins (polycarbonate, acrylic, or polyester). The silane-modified polyethyleneoxide contains both cellulose-binding groups and resin-binding groups, creating a composite material that interfaces effectively with both the natural fiber layer and the synthetic resin layer, thereby resolving the adhesion problem.

Inventive Principle:
Principle #40Composite materials

2Reliability

If adhesion aids are added to enhance bonding between fiber and resin layers, then adhesion properties improve, but the manufacturing process and material composition become more complex

Engineering Contradiction:
Improveadhesion propertiesVSAvoidmanufacturing process
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The adhesion aid layer is prepared in advance as a separate component (silane-modified polyethyleneoxide) that is then applied between the fiber sheet and resin layer during lamination. This preliminary preparation of the adhesion aid allows for standardized manufacturing processes and simplifies the overall production by enabling modular assembly of the laminate structure.

Inventive Principle:
Principle #10Preliminary action

3Strength

If ultrafine cellulose fibers with diameter of 1000 nm or less are used, then transparency and tensile strength are significantly improved, but the challenge of achieving sufficient adhesion with resin layers increases

Engineering Contradiction:
Improvetensile strengthVSAvoidadhesion properties
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The adhesion aid (silane-modified polyethyleneoxide) is specifically localized at the interface between the ultrafine cellulose fiber layer and the resin layer. This localized application ensures that the critical bonding region has enhanced adhesion properties through chemical interactions, while the bulk properties of the ultrafine fibers (transparency and tensile strength) remain intact.

Inventive Principle:
Principle #3Local quality

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 improved adhesion properties between the fiber and resin layers result in a laminate with increased mechanical strength, transparency, and suitability for various applications, including light transmissive substrates and electronic devices.

Implementation Method 1

the resin layer has an adhesion aid, wherein the adhesion aid is at least one selected from an isocyanate compound and an organic silicon compound

Methodology Applied
Scientific EffectChemical Bonding: Chemical Bonding

Data Source

PatentEP3406442B1Laminate and method for producing laminate
Publication Date: 2023.11.29 OJI HLDG CORP
  • EP3406442B1 patent drawingFigure 1~2
  • EP3406442B1 patent drawingFigure 3
  • EP3406442B1 patent drawingFigure 4(a)~4(c)

AI summary

An object of the present invention is to provide a laminate having a fiber layer comprising ultrafine cellulose fibers and a resin layer, wherein the two layers have more excellent adhesion properties. The present invention relates to a laminate having at least one fiber layer comprising cellulose fibers with a fiber width of 1000 nm or less, and at least one resin layer that is contacted with one surface of the fiber layer, wherein the resin layer has an adhesion aid.