Bioabsorbable Self-Cohered Web Materials for Implantable Devices

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing bioabsorbable polymeric web materials lack high porosity, mechanical strength, loft, suppleness, drapability, and tissue compliance, limiting their application in implantable medical devices and thrombogenic agents.

Innovation Solution

A bioabsorbable, non-woven, self-cohered polymeric web material with high porosity is created by stretching an unannealed precursor web material in one or more directions and subsequent heat-setting, resulting in a web with filaments less than 20 microns in diameter and over 90% porosity, which can be used as an implantable medical device or thrombogenic agent.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the web material is made with standard bioabsorbable polymeric compounds, then the material can be used for implantable devices, but the porosity is insufficient (less than 90%)

Engineering Contradiction:
ImproveporosityVSAvoidmechanical strength
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent applies parameter changes by stretching the precursor web material in one or more directions to increase porosity to over 90%, then heat-setting the stretched web to stabilize the structure. This sequence of parameter changes (stretching ratio, temperature) simultaneously achieves high porosity and maintains mechanical strength.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent performs preliminary stretching of the precursor web material before final heat-setting. This preliminary action of stretching creates the high porosity structure needed, and the subsequent heat-setting locks in this structure while developing the required mechanical properties.

Inventive Principle:
Principle #10Preliminary action

2Shape

If the web material is made with standard bioabsorbable polymeric compounds, then the material can be used for implantable devices, but the loft and suppleness are insufficient

Engineering Contradiction:
Improveloft and supplenessVSAvoidmechanical strength
Core Design Contradiction:
ShapeVSReliability

Solution Approach 1:

The patent uses parameter changes by stretching the precursor web material to create a loose, lofty structure with high porosity, then heat-setting at controlled temperatures to stabilize this structure. This process imparts superior loft, suppleness, and drapability while maintaining mechanical strength.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent performs preliminary stretching to create the desired loft and suppleness structure before final heat-setting. This preliminary structural arrangement gives the material its characteristic softness and conformability, which are then locked in during heat-setting.

Inventive Principle:
Principle #10Preliminary action

3Adaptability or versatility

If the web material is made with standard bioabsorbable polymeric compounds, then the material can be used for implantable devices, but the tissue compliance is insufficient

Engineering Contradiction:
Improvetissue complianceVSAvoidmechanical strength
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent applies parameter changes by stretching and heat-setting the web material to create a structure that closely resembles natural tissue architecture. The stretching process creates a compliant, flexible structure that adapts to tissue shapes, while heat-setting maintains the necessary mechanical strength.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent utilizes porous materials with over 90% porosity to achieve high tissue compliance. The porous structure allows for tissue ingrowth, cell migration, and fluid permeation, providing excellent tissue compatibility and compliance while maintaining structural integrity through the porous architecture itself.

Inventive Principle:
Principle #31Porous materials

4Quantity of substance

If the filament diameter is reduced to less than 20 microns, then the porosity increases to over 90%, but the manufacturing precision becomes more difficult to control

Engineering Contradiction:
ImproveporosityVSAvoidfilament diameter control
Core Design Contradiction:
Quantity of substanceVSManufacturing precision

Solution Approach 1:

The patent performs preliminary stretching of the precursor web material to achieve the desired filament fineness and porosity before final heat-setting. This preliminary action allows for better control over filament diameter reduction, as the stretching process can be precisely controlled to achieve the target <20 micron diameter while maintaining manufacturing feasibility.

Inventive Principle:
Principle #10Preliminary action

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 resulting web material exhibits enhanced mechanical strength, loft, suppleness, and tissue compliance, making it suitable for implantable medical devices and effective as a thrombogenic agent, while being bioabsorbable and removable by physiological processes.

Implementation Method 1

stretching an unannealed precursor web material in one or more directions

Methodology Applied
Scientific EffectDeformation: Deformation

Implementation Method 2

subsequent heat-setting

Methodology Applied
Scientific EffectHeat treatment: Heat Treatment

Data Source

PatentEP1909693B1Composite self-cohered web materials
Publication Date: 2014.12.31 WL GORE & ASSOC INC
  • EP1909693B1 patent drawingFigure 1
  • EP1909693B1 patent drawingFigure 1A
  • EP1909693B1 patent drawingFigure 2~2A

AI summary

The present invention is directed to implantable bioabsorbable non-woven self-cohered web materials having a high degree of porosity. The web materials are very supple and soft, while exhibiting proportionally increased mechanical strength in one or more directions. The web materials often possess a high degree of loft. The web materials can be formed into a variety of shapes and forms suitable for use as implantable medical devices or components thereof.