Akron Polymer Systems, Inc.

Other

Boston Scientific Scimed, Inc.

Sumitomo Bakelite Company Limited

Akon Polymer Systems, Inc.

Jiaokai Jing

Frank Wayne Harris

Dong Zhang

Xiaoliang Joe Zheng

Thauming Kuo

Ted Germroth

Brian Michael King

Limin Sun

Bin Wang

Douglas Stephen McWilliams

John D Harvey

Haci Bayram Erdem

Qifeng Zhou

Zhikuan Lu

John Jianhua Chen

Daniel James Horn

Jun Okada

Yusuke Inoue

Mizuho Inoue

Manabu Naito

Doug McWilliams

Hideo Umeda

Ritsuya Kawasaki

Toshihiko Katayama

Ted Calvin Germroth

Frank Harris

Douglas Stephens Mcwilliams

The present invention is directed toward transparent films prepared from soluble aromatic copolyamides with glass transition temperatures greater than 300° C. The copolyamides, which contain pendant carboxylic groups are solution cast into films using N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP), or other polar solvents. The films are thermally cured at temperatures near the copolymer glass transition temperature. After curing, the polymer films display transmittances >80% from 400 to 750 nm, have coefficients of thermal expansion of less than 20 ppm, and are solvent resistant. The films are useful as flexible substrates for microelectronic devices.

Aromatic polyamide films for transparent flexible substrates

A class of solvent resistant, flexible copolyimide substrates having high optical transparency (&#x3e;80% from 400 to 750 nm) that is retained after brief exposure to 300&#xb0; C., near-zero birefringence (&#x3c;0.001) and a maximum CTE of approximately 60 ppm/&#xb0; C. is disclosed. The copolyimides are prepared from alicyclic dianhydrides, aromatic cardo diamines, and aromatic diamines containing free carboxyl groups. The substrates are manufactured from solutions of the copolyimides containing multifunctional epoxides in the form of single layer films, multilayer laminates and glass fiber reinforced composite films. The substrates can be used in the construction of flexible optical displays, and other microelectronic and photovoltaic devices that require their unique combination of properties.

Thermally stable, low birefringent copolyimide films

A flexible substrate with a high optical transparency (&#x3e;80% from 400 to 750 nm) that is retained after exposure to 300&#xb0; C., near-zero birefringence (&#x3c;&#xb1;0.001), and a relatively low CTE (&#x3c;60 ppm/&#xb0; 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.

Thermally stable, flexible substrates for electronic devices

The present invention is directed toward transparent films prepared from soluble aromatic copolyamides with glass transition temperatures greater than 300 C. The copolyamides, which contain pendant carboxylic groups are solution cast into films using N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP), or other polar solvents. The films are thermally cured at temperatures near the copolymer glass transition temperature. After curing, the polymer films display transmittances &#x3e;80% from 400 to 750 nm, have coefficients of thermal expansion of less than 20 ppm, and are solvent resistant. The films are useful as flexible substrates for microelectronic devices.

Films with optical transmittance of &#x3e;80% between 400 and 750 nm and with coefficient of thermal expansion less than 20 ppm/&#xb0; C. are prepared from aromatic polyamides that are soluble in polar organic solvents yet have glass transition temperatures &#x3e;300&#xb0; C. The films are cross-linked in the solid state by heating at elevated temperatures for short periods of time in the presence of multifunctional epoxides. Surprisingly, the optical and thermal properties of the films do not change significantly during the curing process. The temperature required for the crosslinking process to take place can be reduced by the presence of a few free, pendant carboxyl groups along the polyamide backbones. The films are useful as flexible substrates for electronic displays and photovoltaic devices.

Aromatic polyamide films for solvent resistant flexible substrates

Solvent resistant, transparent films prepared from solutions of aromatic polyamides and multi-functional carboxylic acids in polar aprotic solvents are described herein. Solvent resistance is achieved by heating the films for a short time above 300&#xb0; C. near the polyamide Tg. The films have CTEs less than 40 ppm/&#xb0; C. and are optically clear displaying transmittance above 75% between 400 and 750 nm. The films are useful as substrates for flexible electronic devices.

Solvent resistant, aromatic polyamide films for transparent flexible substrates

An optical compensation film is disclosed herein, which is made by uniaxially or biaxially stretching of a multilayer film including a first polymer film having a refractive index profile satisfying the equations of (n+n)/2&#x2265;nand |n&#x2212;n|&#x3c;0.005 and a second polymer film having a refractive index profile satisfying the equations of (n+n)/2&#x3c;nand |n&#x2212;n|&#x3c;0.005, wherein nand nrepresent in-plane refractive indices and nthe thickness-direction refractive index of the films, and wherein said optical compensation film has a positive in-plane retardation that satisfies the relations of 0.7&#x3c;R/R&#x3c;1 and 1&#x3c;R/R&#x3c;1.25, wherein R, R, and Rare in-plane retardations at the light wavelengths of 450 nm, 550 nm, and 650 nm respectively.

Wide-view optical film having reversed wavelength dispersion

The present disclosure, in one aspect, relates to a polyamide solution including an aromatic polyamide and a solvent, wherein the aromatic polyamide includes at least two types of constitutional units, and a change rate of coefficient of thermal expansion (CTE) of a cast film produced by casting the polyamide solution on a glass plate and CTE of the same cast film after being subjected to a heat treatment at temperature of 200&#xb0; C. to 450&#xb0; C. (=CTE after heat treatment/CTE before heat treatment) is 1.3 or less.

Solution of aromatic polyamide for manufacturing display element, optical element, illumination element or sensor element

Films with optical transmittance of &#x3e;80% between 400 and 750 nm and with coefficient of thermal expansion less than 20 ppm/&#xb0; C. are prepared from aromatic polyamides that are soluble in polar organic solvents yet have glass transition temperatures &#x3e;300&#xb0; C. The films are crosslinked in the solid state by heating at elevated temperatures for short periods of time in the presence of multifunctional epoxides. Surprisingly, the optical and thermal properties of the films do not change significantly during the curing process. The temperature required for the crosslinking process to take place can be reduced by the presence of a few free, pendant carboxyl groups along the polyamide backbones. The films are useful as flexible substrates for electronic displays and photovoltaic devices.

A multilayer optical retardation compensation film having at least one positive C-plate and at least one negative C-plate is used in an LCD device. The multilayer film may have a substantially flat wavelength dispersion curve, or the multilayer film combined with other layers in the LCD device may have a substantially flat wavelength dispersion curve. Polymer films for the positive C-plate may be identified according to their absorbance maxima at certain wavelength ranges.

Liquid crystal display having improved wavelength dispersion characteristics

An optical compensation film composition is disclosed herein wherein the optical compensation film is stretched to yield a negative A-plate having a refractive index profile of n&#x3c;n=n. or a biaxial polymer film having a refractive index profile of n&#x3c;n&#x3c;n, the film having been stretched from a film cast from a polymer solution comprising a solvent and a polymer having a moiety of wherein R, R, and Rare each independently hydrogen atoms, alkyl groups, substituted alkyl groups, or halogens, wherein at least one of R, R, and Ris a fluorine atom, and wherein R is hydrogen or a substituent on the styrenic ring.

Optical compensation films based on fluoropolymers

A multilayer optical film includes a wave plate having a refractive index profile of n&#x3e;n&#x2267;nand a fluoropolymer film comprising a moiety of wherein R, R, and Rare each independently hydrogen atoms, alkyl groups, substituted alkyl groups, or halogens, wherein at least one of R, R, and Ris a fluorine atom, wherein R is each independently a substituent on the styrenic ring, n is an integer from 0 to 5 representing the number of the substituents on the styrenic ring, and wherein nand nrepresent in-plane refractive indices and nthe thickness-direction refractive index of the wave plates; wherein said multilayer optical film has a positive in-plane retardation (R) and an out-of-plane retardation (R) that satisfies the equation of |R|&#x3c;R/2 throughout the wavelength range of 400 nm to 800 nm.

Wide-view multilayer optical films

Optical compensation films (positive C-plate) with mesogen anisotropic subunits (OASUs) that have high positive birefringence throughout the wavelength range 400 nm&#x3c;&#x3bb;&#x3c;800 nm are provided. The optical compensation films may be processed by solution casting to yield a polymer film with high birefringence without the need for stretching, photopolymerization, or other processes. Such optical compensation films are suitable for use as a positive C-plate in LCDs, particularly IPS-LCDs.

Optical compensation films with mesogen groups for liquid crystal display

The present invention provides uniaxially stretched polymer films that have a refractive index profile suitable for use as negative A-plates or biaxial birefringent plates in a liquid crystal display (LCD) device. These wave plates can be used to compensate for the phase retardations existing in various modes of LCDs including TN (twisted nematic), VA (vertically aligned), IPS (in-plane switching), and OCB (optically compensated bend), and therefore improving the viewing quality of the displays.

Growing community of inventors

Uniontown, OH, United States of America

Jiaokai Jing