Interdental Tool Composite Shaft Adhesion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional interdental cleaning tools with composite materials are prone to breakage under bending loads due to inadequate bonding between the reinforcement and synthetic resin, leading to increased bending stress and susceptibility to fracture, especially when cleaning between back teeth.

Innovation Solution

The interdental cleaning tool is formed from a composite material containing a synthetic resin, glass reinforcement, and a copolymer with polyolefin and anhydride of an unsaturated carboxylic acid, which enhances the adhesion between the reinforcement and synthetic resin, thereby reducing the likelihood of breakage under bending loads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If reinforcement is added to synthetic resin to increase buckling strength, then the shaft's resistance to bending and buckling improves, but the shaft becomes more prone to breakage under bending loads due to poor adhesion between reinforcement and resin

Engineering Contradiction:
Improvebuckling strengthVSAvoidbreakage resistance
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

A coupling agent is introduced as an intermediary substance between the glass fiber reinforcement and the polypropylene resin. The coupling agent has dual functionality: it bonds chemically with the glass fiber surface through silane groups and simultaneously compatibilizes with the polypropylene matrix, creating strong interfacial adhesion. This mediator prevents reinforcement liberation under bending loads while maintaining buckling strength enhancement.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The chemical parameters of the composite material system are modified by introducing the coupling agent, which changes the interfacial bonding characteristics between reinforcement and matrix. This parameter change transforms the interface from a weak boundary to a strong bonded region, enabling the reinforcement to effectively contribute to both buckling resistance and breakage prevention.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the shaft is made flexible to prevent breakage during cleaning operations, then the shaft can withstand bending loads, but the buckling strength may be compromised

Engineering Contradiction:
Improvebreakage resistanceVSAvoidbuckling strength
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The shaft is constructed as a composite material system combining polypropylene resin, glass fiber reinforcement, and coupling agent. The glass fibers provide stiffness and buckling resistance, while the polypropylene matrix provides flexibility and shock absorption. The coupling agent ensures strong interfacial bonding, allowing the composite to exhibit both flexibility for breakage resistance and sufficient buckling strength through synergistic material combination.

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 enhanced bonding between the reinforcement and synthetic resin increases the shaft's flexibility and buckling strength, reducing the risk of breakage and allowing for effective cleaning between teeth without fracturing, even when subjected to bending loads.

Implementation Method 1

a copolymer having, as structural units, a polyolefin and an anhydride of an unsaturated carboxylic acid... enhances the adhesion between the reinforcement and synthetic resin

Methodology Applied
Scientific EffectAdhesion: Adhesive

Data Source

PatentEP3520731B1Interdental cleaning tool
Publication Date: 2021.07.14 KOBAYASHI PHARMA CO LTD
  • EP3520731B1 patent drawingFigure 1
  • EP3520731B1 patent drawingFigure 2
  • EP3520731B1 patent drawingFigure 3

AI summary

An interdental cleaning tool (1) that includes a base (10) that has a shaft (20) shaped to be capable of being inserted between teeth, the base (10) being formed from a composite material that contains a synthetic resin, a reinforcement containing glass, and a copolymer having, as structural units, a polyolefin and an anhydride of an unsaturated carboxylic acid.