E.i. Dupont De Nemours and Company

The Ohio State University

E. I. Du Pont De Nemours

Rayitek Hi-tech Film Company, Ltd., Shenzhen

Kuppusamy Kanakarajan

Brian C Auman

Thomas Eugene Dueber

John A Kreuz

Michael W J West

Govindasamy Paramasivam Rajendran

Arnold Frances

Christopher Robert Becks

ZhenZhong Wang

Jonathan Robert Parquette

Xi Ren

Karthikeyan Perumal

A method of preparing a colorless transparent copolyamide-imide resin solution and its fabrication as a thin film has been disclosed. The method details formulations derived from a reaction between one or more units of dianhydride and one or more units of diamine monomers with one or more of the monomers containing fluorine atoms in their structural unit. It enables the fabrication of thin films with superior thermal and mechanical properties along with co-efficient of thermal expansion values as low as 2 ppm/&#xb0; C. and a tensile modulus as high as 9 GPa. The transparent copolyamide-imide film thus prepared has the potential for utilization in flexible displays such as substrates for thin film transistors (TFT), touch sensor panels (TSP) and cover window in organic light emitting diode (OLED) and liquid crystal display (LCD) applications.

Colorless transparent copolyamide-imide films with high modulus and low coefficient of thermal expansion and preparation thereof

The present disclosure is directed to a method of increasing optical density by incorporating carbon black in to a colored polyimide composition to obtain a colored polyimide film. The colored polyimide film has 48 to 94 weight percent of a polyimide, 5 to 25 weight percent pigment and 0.05 to 2 weight percent carbon black.

Colored polyimide films and methods relating thereto

Provided is a multi-layer article comprising an electrically conductive metal layer adheringly contacting the surface of a polymeric composite film less than 500 &#x3bc;m in thickness, having a surface, the polymeric composite film comprising a polymer and a plurality of surface-modified hexagonal boron nitride particles dispersed therewithin. A process of film casting onto a conductive metal layer is provided.

Multi-layer article for flexible printed circuits

The invention is directed to polyimide based adhesives having a coefficient of thermal expansion ('CTE') equal to or below 50 ppm/&#xb0; C. The adhesives of the present invention contain a polyimide base polymer present in the overall adhesive in an amount from 25 to 95 weight percent. The polyimide base polymer has a glass transition temperature ('T') in a range of from about 150 to about 300&#xb0; C. and typically has a coefficient of thermal expansion above 50 ppm/&#xb0; C. The polyimide based adhesives of the invention also contain an aramid micro fiber filler in an amount from 5 to 75 weight percent, based upon the total weight of the polyimide based adhesive. The fiber filler can be used to lower CTE of the overall adhesive to match (or nearly match) the CTE of other materials like metal, silicon wafers, other polymers (including polyimide) and the like.

Aramid filled polyimides having advantageous thermal expansion properties, and methods relating thereto

The present invention is directed to coverlay compositions derived from two-layer polyamic acid-based composites having a cover layer and adjacent thereto an adhesive layer wherein the cover layer comprises polyamic acid and other additives allowing the composition to be photosensitive and aqueous base developable, and where the adhesive layer can form a polyimide having a glass transition temperature between 170 and 250&#xb0; C. The two-layer coverlay compositions of the present invention are used to encapsulate metal circuit traces formed on a flexible printed circuit base substrate. These two-layer compositions are particularity useful due to having an overall in-plane CTE between 10 and 40 ppm/&#xb0; C. a range that is useful in avoiding unwanted curling of a flexible printed circuit when used as a polyimide-based coverlay material.

Polyimide composite coverlays and methods and compositions relating thereto

The invention relates to low-temperature curable photosensitive compositions containing a polyamic acid, which compositions are developable in aqueous alkaline solutions and are curable, at a temperature of at least 160&#xb0; C. and up to 200&#xb0; C., to low modulus polyimides suitable for use in electronic circuitry applications, and which are particularly suitable for use in flexible circuit applications where low curl, low temperature curing, and good adhesion is a significant advantage.

Low-temperature curable photosensitive compositions

The present invention relates to a polyimide adhesive composition having a polyimide derived from an aromatic dianhydride and a diamine component, where the diamine component is preferably about 50 to 90 mole % of an aliphatic diamine and about 10 to 50 mole % of an aromatic diamine. In one embodiment, the aliphatic diamine has the structural formula HN&#x2014;R&#x2014;NHwherein R is hydrocarbon from Cto Cand the polyimide adhesive has a glass transition temperature in the range of from 150&#xb0; C. to 200&#xb0; C. The present invention also relates to compositions comprising the polyimide adhesive of the present invention, including polyimide metal-clad laminate useful as flexible circuit when metal traces are formed out of the metal used in flexible, rigid, or flex-rigid circuit applications.

Low temperature polyimide adhesive compositions and methods relating thereto

The polyimides of the present invention are derived from aliphatic diamines and show advantageous arc tracking performance (i.e., low arc tracking). These polyimides can be cured at low temperatures making them suitable as coverlay compositions in electronic circuitry. In addition, these polyimides are soluble and excellent in heat resistance and adhesion properties, showing a low dielectric constant even at 10 GHz or more.

Low temperature cure polyimide compositions resistant to arc tracking and methods relating thereto

A process of making flexible multilayer polyimide metal-clad laminates, and their preparation, having at least one layer of aromatic polyimide bonded to at least one layer of a metallic substrate using a heat-sealable copolyimide adhesive containing repeating imide units derived from 4,4'-oxydiphthalic dianhydride and an aromatic ether diamine. The laminates are used in flexible printed circuits and tape automated bonding applications. Additionally, the metallic substrate may be directly coated with the copolyimide adhesive and used as a single-clad laminate for flexible printed circuits.

Flexible multi-layer polyimide film laminates and preparation thereof

Flexible multilayer polyimide metal-clad laminates, and their preparation, having at least one layer of aromatic polyimide bonded to at least one layer of a metallic substrate using a heat-sealable copolyimide adhesive containing repeating imide units derived from 4,4'-oxydiphthalic dianhydride and an aromatic ether diamine. The laminates are used in flexible printed circuits and tape automated bonding applications. Additionally, the metallic substrate may be directly coated with the copolyimide adhesive and used as a single-clad laminate for flexible printed circuits.

Growing community of inventors

Dublin, OH, United States of America

Kuppusamy Kanakarajan