In 1969, Bob Gore was researching a process for stretching extruded PTFE into pipe thread tape when he discovered that the polymer could be "expanded" into a porous form of PTFE, characterized by extremely high strength and porosity.
He and others had attempted to stretch rods of PTFE by about 10%.
His discovery of the right conditions for stretching PTFE was a happy accident, born partly of frustration.
Instead of slowly stretching the heated material, he applied a sudden, accelerating yank.
The solid PTFE unexpectedly stretched about 800%, forming a microporous structure that was about 70% air.

A patent application for expanded PTFE was filed on May 21, 1970, and eventually two separate patents were issued, one for the product, and another for the processes for making the product.

Bob Gore continued to investigate the properties of the new material, studying the effectiveness of different PTFE resins.
 He also worked with others to develop techniques for stretching the material both one-dimensionally, to create long filaments, and two-dimensionally, to create sheets of the membrane.
Two-dimensional stretching created sheets with greater strength, porosity, and air flow, opening up possibilities for many new applications.

By 1971, Gore was experimenting with laminates, combining the stretched membrane with supporting materials for added strength.
 Based on this work, the company developed a waterproof laminate called expanded polytetrafluoroethylene (ePTFE), now trademarked as Gore-Tex.
In 1969, Bob Gore was researching a process for stretching extruded PTFE into pipe thread tape when he discovered that the polymer could be "expanded" into a porous form of PTFE, characterized by extremely high strength and porosity. He and others had attempted to stretch rods of PTFE by about 10%. His discovery of the right conditions for stretching PTFE was a happy accident, born partly of frustration. Instead of slowly stretching the heated material, he applied a sudden, accelerating yank. The solid PTFE unexpectedly stretched about 800%, forming a microporous structure that was about 70% air.
A patent application for expanded PTFE was filed on May 21, 1970, and eventually two separate patents were issued, one for the product, and another for the processes for making the product.
Bob Gore continued to investigate the properties of the new material, studying the effectiveness of different PTFE resins.  He also worked with others to develop techniques for stretching the material both one-dimensionally, to create long filaments, and two-dimensionally, to create sheets of the membrane. Two-dimensional stretching created sheets with greater strength, porosity, and air flow, opening up possibilities for many new applications.
By 1971, Gore was experimenting with laminates, combining the stretched membrane with supporting materials for added strength.  Based on this work, the company developed a waterproof laminate called expanded polytetrafluoroethylene (ePTFE), now trademarked as Gore-Tex.
Robert W. Gore