History of
Flexible Circuits

1903

Hansen's Patent — The First Flex Circuit

Albert Hansen files an English patent describing flat metal conductors on paraffin-coated paper — the earliest documented description of what we now recognize as a flexible circuit. Thomas Edison's lab books from the same period show similar thinking.

1947

Printed Circuit Techniques Published

Cledo Brunetti and Roger W. Curtis publish 'Printed Circuit Techniques' (National Bureau of Standards Circular 468), including discussion of circuits on flexible insulating materials — establishing the concept formally in scientific literature.

1950s

Sanders Associates — Commercial Development

Victor Dahlgren and Royden Sanders at Sanders Associates (Nashua, NH) develop and patent processes for printing and etching flat conductors on flexible substrates to replace wire harnesses. The first serious commercial flex circuit development.

1960s–70s

Military Adoption

Rigid-flex circuits gain widespread adoption among military and defense product designers. Ability to package complex interconnections in tight, vibration-resistant, connector-free assemblies makes flex ideal for aerospace and defense.

1980s–90s

KAPTON and Consumer Electronics

KAPTON polyimide from DuPont becomes the dominant flex substrate. Consumer electronics manufacturers adopt flex circuits for thinner, lighter products. Compaq uses rigid-flex in laptop hinges — passing tens of thousands of flex cycles during qualification.

2000s

Smartphone Revolution

The proliferation of smartphones drives massive growth in flex circuit demand. Space and weight savings make flex circuits essential for the mobile era.

2013+

Universal Adoption

Rigid-flex in consumer laptops becomes commonplace. Flex circuits appear in virtually every electronic product category — from medical implants to automotive safety systems to wearable devices.