Thermally stable, flexible substrates for electronic devices

US11059742B2 · kind B2 · utility

Assignee

• Akron Polymer Systems, Inc. · US

Inventors

• Limin Sun · Copley, US
• Dong Zhang · Uniontown, US
• Jiaokai Jing · Uniontown, US
• Frank W. Harris · Akron, US
• Zhikuan Lu · Hudson, US
• Xiaoliang Zheng · Hudson, US

Key dates

• Filing date: May 10, 2013
• Grant date: Jul 13, 2021
• Expiry date: May 10, 2033

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31623
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A flexible substrate with a high optical transparency (>80% from 400 to 750 nm) that is retained after exposure to 300° C., near-zero birefringence (<±0.001), and a relatively low CTE (<60 ppm/° C.) is disclosed. The substrate may be manufactured as single layer, polyimide films and as a multi-layer laminate comprising a polyimide layer and a thin glass layer. The polyimides may include alicyclic dianhydrides and aromatic, cardo diamines. The films formed of the polyimides can serve as flexible substrates for optical displays and other applications that require their unique combination of properties.