Laminated Body with Styrene Elastomer Adhesive for Rubber Bonding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional laminates with ethylene-vinyl alcohol copolymer layers require adhesives for bonding with rubber materials, which is inconvenient and lacks superior interlayer adhesiveness and flex resistance.

Innovation Solution

A laminate structure comprising gas barrier layers and elastomer layers with a styrene elastomer adhesive layer having an iodine value of 200-300, allowing crosslinking reactions for enhanced adhesion to rubber materials and interlayer adhesiveness, while maintaining gas barrier properties and flex resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If conventional laminates are bonded to rubber materials using adhesives, then bonding is achieved, but the process becomes inconvenient and interlayer adhesiveness is insufficient

Engineering Contradiction:
Improvebonding convenienceVSAvoidinterlayer adhesiveness
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The laminate is designed to bond with rubber materials through its own inherent properties (elastomer layers with specific glass transition temperatures and functional groups) rather than requiring external adhesives. The laminate serves its own bonding function, eliminating the need for separate adhesive application steps while achieving reliable interlayer adhesion.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The laminate uses a composite structure combining gas barrier layers (ethylene-vinyl alcohol copolymer) with elastomer layers (polyurethane, polyester, or polyamide) that have specific bonding capabilities. This composite design allows the laminate itself to provide both barrier functionality and adhesive bonding to rubber materials without requiring additional adhesive materials.

Inventive Principle:
Principle #40Composite materials

2Reliability

If multiple resin layers are laminated to improve gas barrier properties, then gas barrier performance is enhanced, but flex resistance and interlayer adhesiveness deteriorate

Engineering Contradiction:
Improvegas barrier propertiesVSAvoidflex resistance
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

Different layers in the laminate are assigned different local properties: gas barrier layers provide barrier functionality while elastomer layers provide flexibility and adhesion. The elastomer layers are specifically positioned between the gas barrier layers and rubber materials, creating local zones of flexibility that prevent cracking during flexing while maintaining overall gas barrier integrity.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The laminate combines rigid gas barrier layers with flexible elastomer layers in a composite structure. The elastomer layers act as stress-absorbing intermediates that prevent the brittle gas barrier layers from cracking during flexing, thereby maintaining both gas barrier properties and flex resistance simultaneously.

Inventive Principle:
Principle #40Composite materials

3Reliability

If elastomer layers are added to improve adhesion to rubber materials, then bonding is enhanced, but the structure becomes more complex

Engineering Contradiction:
Improveadhesion to rubber materialVSAvoidlaminate structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The elastomer layers are designed to perform multiple functions simultaneously: they provide adhesion to rubber materials through their chemical composition (polyurethane, polyester, or polyamide with specific glass transition temperatures), maintain flexibility during flexing, and ensure interlayer adhesion between gas barrier layers and rubber materials. This multi-functionality reduces the need for additional specialized layers, simplifying the overall structure.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 laminate achieves high adhesion to rubber materials, improved interlayer adhesiveness, and enhanced flex resistance without the need for adhesives, making it suitable for applications like food packaging and pneumatic tire liners.

Implementation Method 1

the adhesive layer (B1) is capable of adhering to a rubber material more favorably through a crosslinking reaction such as vulcanization

Methodology Applied
Scientific EffectCrosslinking reaction: Chemical Bonding

Implementation Method 2

a gas barrier resin has an oxygen permeation rate determined under a condition at 20 °C and 65% RH in accordance with a method prescribed in JIS K 71262

Methodology Applied
Scientific EffectPermeation resistance: Permeation

Data Source

PatentEP3466683B1Laminated body, multi-layered structure, and production methods therefor
Publication Date: 2022.05.11 KURARAY CO LTD
  • EP3466683B1 patent drawingFigure 1(a)~1(b)
  • EP3466683B1 patent drawingFigure 2(a)~2(b)
  • EP3466683B1 patent drawing

AI summary

Provided are: a laminate having an outer surface thereof that is highly adhesive to a rubber material, and having sufficient gas barrier properties, interlayer adhesiveness and flex resistance; a multilayered structure including such a laminate; and a method for producing the same. A laminate including: a plurality of gas barrier layers (A) formed from a polymer including a gas barrier resin; and an elastomer layer (B) including at least one adhesive layer (B1), wherein a sum of number of the gas barrier layers (A) and number of the elastomer layer (B) is 5 or greater and 300 or less, the adhesive layer (B1) is laminated as at least an outermost layer, and the adhesive layer (B1) includes a styrene elastomer and is formed from a polymer having an iodine value of 200 or greater and 300 or less.