Auxetic Support Bands for Bottom Garments and Exposure Prevention

Solution Overview

Problem

Conventional support bands in bottom garments, made of elastic materials, exhibit a positive Poisson ratio, leading to discomfort, abrasion, and exposure issues due to high restoring forces required to maintain garment position.

Innovation Solution

Incorporation of auxetic devices with a negative Poisson ratio into support bands and panels, which expand vertically when stretched horizontally, increasing surface area and reducing stress per unit area.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional elastic support bands with positive Poisson ratio are used to maintain garment position, then the garment remains in desired position, but the restoring force causes stress, discomfort, abrasion, and potential exposure

Engineering Contradiction:

Improvegarment position stabilityVSAvoidstress and discomfort to wearer

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the fundamental material parameter from positive Poisson ratio (conventional elastic) to negative Poisson ratio (auxetic), fundamentally altering how the support band responds to stretching while maintaining position stability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The support band combines auxetic material with conventional elastic materials to create a composite structure that leverages the unique properties of auxetic materials (negative Poisson ratio) while maintaining the flexibility and comfort of elastic materials

Inventive Principle:

Principle #40Composite materials

2Reliability

If higher restoring force is applied to prevent garment sliding, then the garment maintains position better, but the stress and abrasion on the wearer increases

Engineering Contradiction:

Improvegarment position stabilityVSAvoidabrasion and chafing

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the fundamental material parameter from positive Poisson ratio (conventional elastic) to negative Poisson ratio (auxetic), fundamentally altering how the support band responds to stretching while maintaining position stability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent converts the harmful effect of high restoring force into a beneficial effect by using auxetic material that expands laterally when stretched, providing position stability through a different mechanism that does not rely on high compressive force against the body

Inventive Principle:

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

3Shape

If conventional elastic material is used for support band, then the material narrows when stretched, but this creates gap situations and exposure when bending over

Engineering Contradiction:

Improvesupport band narrowingVSAvoidcoverage and exposure prevention

Core Design Contradiction:

ShapeVSReliability

Solution Approach 1:

The patent changes the fundamental material parameter from positive Poisson ratio (conventional elastic) to negative Poisson ratio (auxetic), fundamentally altering how the support band responds to stretching while maintaining position stability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent inverts the conventional behavior of elastic materials by using auxetic material that expands laterally when stretched instead of narrowing, thereby preventing gap situations and exposure when the garment is stretched during movement

Inventive Principle:

Principle #13The other way round (Inversion)

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

Provides a comfortable and conforming fit by maintaining garment position while minimizing stress and preventing exposure, enhancing wearer comfort and reducing abrasion.

Implementation Method 1

the auxetic device disclosed herein may be formed of an elastomer material with a negative Poisson ratio such that the auxetic device is configured to expand vertically when it is stretched horizontally

Methodology Applied

Scientific EffectNegative Poisson ratio: Auxetic Materials

Implementation Method 2

The auxetic device may provide an increased surface area where stretched which may enhance the comfort to wearer of garment

Methodology Applied

Scientific EffectAuxetic expansion: Auxetic Materials

Data Source

PatentUS20250280907A1Auxetic bands and panels for bottom garments and garments incorporating the same

Publication Date: 2025.09.11 THE H D LEE CO INC

AI summary

A garment includes an auxetic device having a first end, a second end opposite the first end, a top edge extending between the first end and the second end, and a bottom edge opposite the top edge. The first end and the second end are fixed to another portion of garment. At least one of the top edge or the bottom edge is free between the first end and the second end. The auxetic device has a Poisson ratio less than or equal to zero when stretched in a direction extending between the first end and the second end.