Abstract: A process for producing polyimide microfine particles which is amenable to free control of particle morphology and particle diameter distribution is provided. A polyamic acid and a polyimide, each in the form of microfine particles with good monodispersibility, are also provided. There is also provided a process for producing polyimide microfine particles from a tetracarboxylic anhydride and a diamine compound which comprises (a) a first step of preparing a first solution containing the tetracarboxylic anhydride and a second solution containing the diamine compound, (b) a second step of mixing the first and second solutions and causing a polyamic acid to precipitate in the form of microfine particles from the mixed solution under ultrasonic agitation, and (c) a third step of imidating the polyamic acid particles to provide the objective polyimide in the form of microfine particles.

Abstract: The present invention is directed to polyimide systems which simultaneously offer low toxicity, a high glass transition temperature, excellent thermal oxidative stability, and desirable processing characteristics. These various polyimide systems include mixtures of monomeric reactants, polyimide-precursor reaction products, polyimides, and polyimide-containing articles. In one aspect of the invention, the mixture of monomeric reactants includes at least one dia-nhydride or a derivative thereof, and at least one diamine. The diamine may be 4,4′-[1,4-phenylene-bis(1-methylethylidene)]bisaniline, 4,4′-[1,3-phenylene-bis(1-methylethylidene)]bisaniline, and/or a derivative thereof. The diamine also may include a phenylenediamine, 2,2-bis[4-(4-aminophenoxyl)phenyl]propane, 4,4′(1,4-phenylene-bismethylene)bisaniline, and/or a derivative thereof. In addition, the mixture may include a reactive end-capping agent and/or a non-reactive end-capping agent.

Abstract: The present invention provide a novel polyimide which is soluble in organic solvents and excels in heat resistance, and to a process for producing the polyimide. The polyimide of the present invention comprises a repeating unit represented by the formula (1) and having a number average molecular weight of from 4,000 to 200,000. wherein X is —SO2— or —C(═O)—OCH2CH2O—C(═O)—, and R1, R2, R3 and R4 are independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

Abstract: A polyimide precursor solid residuum is an admixture of an aromatic dianhydride or derivative thereof and an aromatic diamine or dervative thereof plus a complexing agent, which is complexed with the admixture by hydrogen bonding. The polyimide precursor solid residuum is effectively employed in the preparation of polyimide foam and the fabrication of polyimide foam structures.

Abstract: Polyimide copolymers were obtained containing 1,3-bis(3-aminophenoxy)benzene (APB) and other diamines and dianhydrides and terminating with the appropriate amount of a non-reactive endcapper, such as phthalic anhydride. Homopolymers containing only other diamines and dianhydrides which are not processable under conditions described previously can be made processable by incorporating various amounts of APB, depending on the chemical structures of the diamines and dianhydrides used. Polyimides that are more rigid in nature require more APB to impart processability than polyimides that are less rigid in nature. The copolymers that result from using APB to enhance processability have a unique combination of properties including: excellent thin film properties, low pressure processing (200 psi and below), improved toughness, improved solvent resistance, improved adhesive properties, improved composite mechanical properties, long term melt stability (several hours at 390 C.), and lower melt viscosities.

Abstract: The invention relates to a photosensitive polyimide resin composition comprising (A) a polyamic acid having, in its main chain, repeating units formed from a polycondensation product of at least one tetracarboxylic acid or tetracarboxylic anhydride thereof with at least one diamine compound, and having actinic ray-sensitive functional groups at both terminals thereof; (B) a photosensitive auxiliary having a photopolymerizable functional group; (C) a photopolymerization initiator; and (D) a solvent, wherein 1 the polyamic acid is such that when the repeating unit represented by the formula (1) is defined as a unit molecular weight, a unit molecular weight per carboxyl group (unit molecular weight/COOH) falls within a range of from 200 to 300, and 2 the photosensitive resin composition permits the formation of a polyimide film having a residual stress of 40 MPa or lower and a coefficient of thermal expansion of 30 ppm/.degree. C.

Abstract: This invention relates to methods of preparing dibasic acids, such as adipic acid for example, by oxidizing a hydrocarbon with a gas containing an oxidant, preferably oxygen. A respective hydrocarbon is reacted with a gaseous oxidant to form dibasic acid in a mixture which preferably contains a solvent, a catalyst, and an initiator. The temperature of the mixture is then lowered to a point at which solid dibasic acid is precipitated, while maintaining a single liquid phase. At least part of the formed acid is then removed.

Abstract: A diamine which is useful in preparing a new flexible polyamide and polyimide with an aromatic dicarboxylic acid and a tetracarboxylic dianhydrides, respectively, has a general formula as follows: ##STR1## wherein R.sub.1 is methyl (--CH.sub.3) and n is an integer ranging from 1 to 4.

Abstract: A compound of the formula: ##STR1## wherein Ar.sup.

Abstract: Polyimide copolymers were obtained containing 1,3-bis(3-aminophenoxy)benzene (APB) and other diamines and dianhydrides and terminating with the appropriate amount of reactive endcapper. The reactive endcappers studied include but should not be limited to 4-phenylethynyl phthalic anhydride (PEPA), 3-aminophenoxy-4'-phenylethynylbenzophenone (3-APEB), maleic anhydride (MA) and nadic anhydride (5-norbornene-2,3-dicarboxylic anhydride, NA). Homopolymers containing only other diamines and dianhydrides which are not processable under conditions described previously can be made processable by incorporating various amounts of APB, depending on the chemical structures of the diamines and dianhydrides used. By simply changing the ratio of APB to the other diamine in the polyimide backbone, a material with a unique combination of solubility, Tg, Tm, melt viscosity, toughness and elevated temperature mechanical properties can be prepared.

Abstract: Water soluble polyalkanolamides and a process to prepare same by reacting polycarboxylic acid or its anhydride, ester or halide derivative with at least one alkanolamine and optionally with a polyamine and removing the condensation byproduct water, alcohol or hydrogen halide.

Abstract: A polyimide resin having good thermal stability and good adhesion to a metal foil is disclosed. The polyimide resin is prepared by dissolving at least one diamine in a polar aprotic solvent followed by the addition of an aromatic tetracarboxylic acid dianhydride to the solution of the aromatic diamines to prepare a polyamic acid solution, imidizing this solution to a polyimide resin by heating at a temperature above 250.degree. C., the polar aprotic solvent comprising at least 1 weight % of acetone. Polyimide laminates with a metal foil, such as a copper foil, are also described. The laminates may be used to form flexible printed circuit boards.

Abstract: A polyimide precursor solution having a high concentration yet low viscosity, a polyimide coating film having satisfactory physical properties which is prepared from the polyimide precursor solution, and a process for producing a polyimide coating film using the polyimide precursor solution. The polyimide precursor solution has dissolved therein a specific salt of a diamine and a tetracarboxylic acid and/or a dicarboxylic acid-dialkyl ester in a high concentration, the diamine and the tetracarboxylic acid and/or the dicarboxylic acid-dialkyl ester being capable of forming a polyimide. Also disclosed is a polyimide coating film obtained by heating the solution to cause imidization and a process for producing the polyimide coating film.

Abstract: Polyimide polymers from 3,4,3',4'-biphenyltetracarboxylic dianhydride and 3,4,3',4'-benzophenonetetracarboxylic dianhydride and a diamine such as p-phenylenediamine exhibit a high glass transition temperature, high thermal oxidative stability and low moisture regain, useful for structural applications.

Abstract: A fully imidized cresylic acid soluble polymer comprising 4,4'- oxydiphthalic anhydride (ODPA), 3,4,3',4',-biphenyltetracarboxylic dianhydride (BPDA), 3,4'-oxydianiline (ODA), and 4,4'-oxydianiline (DAPE) that can be used as a coating material such as a wire coated enamel. The polyimide has relatively low viscosity and high percent solids by substituting some of the 3,4'oxydianiline with 4,4'oxydianiline. Substitution with the 4,4'oxydianiline can be accomplished up to 25% on the molar basis without losing the fully imidized, cresol solubility characteristics.

Abstract: Biodegradable polyesteramides as defined in the specification obtained by reacting a mixture consisting essentially of(a1) from 95 to 99.9% by weight of a polyesteramide,(a2) from 0.1 to 5% by weight of a divinyl ether, and(a3) from 0 to 5 mol % of compound D as defined in the specification, and other biodegradable polymers and thermoplastic molding compositions, processes for the preparation thereof, the use thereof for producing biodegradable moldings, and adhesives, biodegradable moldings obtained from the polymers and molding compositions according to the invention.

Abstract: A diaminobenzene derivative represented by formula (1), and a polyimide obtained by reacting a diamine containing at least 1 mol % of said diaminobenzene derivative, with a tetracarboxylic acid and its derivatives to obtain a polyimide precursor and ring-closing it, having a repeating unit represented by formula (2), and a liquid crystal alignment film containing said polyimide. ##STR1## P is a single bond or --O--, --COO--, or --CONH--, Q is a cyclic substituent selected from an aromatic ring, an aliphatic ring, a hetero ring and their substitution products, R.sup.1 is an aliphatic ring, and R.sup.2 is C.sub.1-22 straight chain alkyl group, A is a tetravalent organic group constituting a tetracarboxylic acid, B is a bivalent organic group constituting a diamine.

Abstract: A conductive composition including a mixture of a reaction product ofa hole transporting hydroxy functionalized aryl amine,a hydroxy functionalized arylamine that is different from the hole transporting hydroxy functionalized aryl amine,a cross linkable polyamide, andand an acid capable of simultaneously cross linking the polyamide and oxidizing a portion of the hydroxy functionalized arylamine,the mixture of a reaction product includinga hole transporting hydroxy functionalized aryl amine andan oxidized hydroxy functionalized aryl amine in aa crosslinked polyamide matrix.Other embodiments including processes for applying the aforementioned composition and processes for using devices containing the compositions in high speed laser printing and related printing systems are also disclosed.

Abstract: The present invention provides novel polyamic acids and polyimide optical alignment layers for inducing alignment of a liquid crystal medium. The novel compositions comprise crosslinking diamines containing a C.sub.3 -C.sub.20 linear or branched hydrocarbon chains containing 1 to 4 carbon-carbon double bonds. The invention further describes liquid crystal displays comprising the novel polyimide optical alignment layers.

Abstract: The polyimides are derived from solutions of at least one low-boiling organic solvent, e.g. isopropanol containing a mixture of polyimide-forming monomers. The monomeric solutions have an extended shelf life at ambient (room) temperatures as high as 80.degree. C. and consist essentially of a mixture of monoalkyl ester-acids, alkyl diester-diacids and aromatic polyamines wherein the alkyl radicals of the ester-acids are derived from lower molecular weight aliphatic secondary alcohols having 3 to 5 carbon atoms per molecule such as isopropanol, secondary butanol, 2-methyl-3-butanol, 2 pentanol or 3-pentanol. The solutions of the polyimide-forming monomers have a substantially improved shelf-life and are particularly useful in the aerospace and aeronautical industry for the preparation of polyimide reinforced fiber composites such as the polyimide cured carbon composites used in jet engines, missiles, and for other high temperature applications.

Abstract: A polyimide for optical communications has a monomer, represented by the formula (1), as a repeating unit: ##STR1## wherein X.sub.1 and X.sub.2 are independently selected from the group consisting of halogen atom, halogenated alkyl group, halogenated aromatic ring group, --NO.sub.2, --OR.sup.1 and --SR.sup.1 (where R.sup.1 is selected from the group consisting of halogenated alkyl and halogenated aromatic ring groups); and Z is selected from the group consisting of divalent halogenated aliphatic hydrocarbon, divalent halogenated aliphatic cyclic hydrocarbon and divalent halogenated aromatic hydrocarbon. Thus, light absorption loss at a near infrared light wavelength range can be minimized by using the polyimide, so that the polyimide is very useful as an optical material in the optical communications field using light of a near infrared light region.

Abstract: The present invention provides a novel soluble polyimide resin which is superior in solubility in solvents and transparency, which is useful particularly in electronics and optronics fields, and which has good processability; a process for production of the resin; and a solution composition of the resin. A soluble polyimide resin containing, as part or the whole of the diamine units, a 2,5(or 6)-bis(aminomethyl)bicyclo[2.2.1]heptane and having a light transmittance of 60% or more in a range of wavelength larger than 400 nm in an ultraviolet-visible light spectrum measured for a film of 10-.mu.m thickness; a process for production of the resin; and a solution composition of the resin.

Abstract: Polyimide is produced by reacting two kinds of diamine compounds consisting of diaminopolysiloxane and a hydroxyl group-containing diamine or three kinds of diamine compounds consisting of diaminopolysiloxane, a hydroxyl group-containing diamine and an aromatic or alicyclic diamine with a 4,4'-(hexafluoroisopropylidene)diphthalic acid dianhydride, thereby once forming a polyamic acid, and subjecting the polyamic acid to polyimidization reaction. The resulting polyimide itself is soluble in low boiling organic solvents for general purpose use, typically methyl ethyl ketone. A photosensitive composition comprising the polyimide, a photo crosslinking agent and a photo acid-generating agent forms a negative type polyimide pattern upon development with an aqueous alkali solution.

Abstract: The present invention provides polyimides and co-polyimides that are organosoluble. The polyimides and co-polyimides are prepared from an aromatic diamine having tert-butyl group, i.e., 1,4-bis(4-aminophenoxy)-2-tert-butyl-benzene, or its mixture with other diamines, and a mixture of dianhydrides that containing DSDA or 6FDA or other diether-dianhydrides.

Abstract: The new diamine, "3,3',5,5'-tetramethyl-2,2-bis[4-(4-amino-phenoxy)phenyl]propane" was synthesized and used to prepare high performance soluble engineering plastics by polycondensation. The polymer can be polyamides, polyimides or poly(amide-imide)s. These polymers exhibit excellent solubility, processability, heat resistance and mechanical performance.

Abstract: A composition for a polyimide type liquid crystal aligning film characterized in that a diamino compound constituting polyimide contains one, two or more diamine selected from 4,4'-diaminodiphenyl methane, 3,3'-dimethyl-4,4'-diaminodiphenyl methane, 2,2'-dimethyl-4,4'-diaminodiphenyl methane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenyl methane and 4,4'-ethylene di-meta-toluidine.

Abstract: A diamine-containing polyamic acid alignment layer material provided by the polymerization of aromatic diamine and dianhydride, and having an excellent coating, adhesion and stability. After the polyamic acid alignment layer material is coated and cured at a high temperature, a polyamic acid alignment layer having a pretilt angle of below 2 degrees is formed due to a close ring reaction. The polyamic acid alignment layer with a low pretilt angle can be used in a TN (twisted nematic) type liquid crystal display.

Abstract: Polyimide is produced by reacting two kinds of diamine compounds consisting of diaminopolysiloxane and a hydroxyl group-containing diamine or three kinds of diamine compounds consisting of diaminopolysiloxane, a hydroxyl group-containing diamine and an aromatic or alicyclic diamine with a dicarboxylic acid anhydride having a 2,5-dioxotetrahydrofuryl group as one acid anhydride group, thereby once forming a polyamic acid, and subjecting the polyamic acid to polyimidization reaction. The resulting polyimide itself is soluble in low boiling organic solvents for general purpose use, typically methyl ethyl ketone. A photosensitive composition comprising the polyimide, a photo crosslinking agent and a photo acid-generating agent forms a negative type polyimide pattern upon development with an aqueous alkali solution.

Abstract: This invention relates the novel diamines, the polyimide oligomers and the polyimides derived therefrom and to the method of preparing the diamines, oligomers and the polyimides. The thermoplastic polyimides derived from the aromatic diamines of this invention are characterized as having a high glass transition temperature, good mechanical properties and improved processability in the manufacture of adhesives, electronic and composite materials for use in the automotive and aerospace industry. The distinction of the novel aromatic diamines of this invention is the 2,2',6,6'-substituted biphenyl radicals which exhibit noncoplanar conformation that enhances the solubility of the diamine as well as the processability of the polyimides, while retaining a relatively high glass transition temperature and improved mechanical properties at useful temperature ranges.

Abstract: Disclosed is a method of making an imide-containing polymer by bulk or melt polymerizing monomers. A mixture is formed of (1) a cyclic compound that contains an anhydride group and a second group which is an anhydride, a carboxylic acid, or an ester and (2) a diamine in an amount stoichiometric .+-.5 mole % of stoichiometric with the amount of cyclic compound. An end capper may also be included in the mixture to control the molecular weight but no solvent is used. A polyimidesiloxane can be made by using a siloxane-containing diamine. The mixture is heated to a temperature above the T.sub.g or T.sub.m of the polymer but below its degradation temperature.

Abstract: An optical alignment composition including self-photosensitive polyimide having a benzophenone moiety and an active hydrogen moiety, and an LCD having the alignment layer formed of the optical alignment composition are provided. Since the alignment layer with excellent thermal stability and improved pretilt angle is obtained, the LCD having excellent performance can be manufactured.

Abstract: The present invention provides a series of easily processable poly(ether-imide)s that are organic-soluble and can afford colorless films, their organic solutions and their manufacturing process. The poly(ether-imide) is prepared from a dianhydride and a diamine, wherein the dianhydride is a bis(ether anhydride) having tert-butyl group, i. e. 1,4-bis(3,4-dicarboxyphenoxy)-2-tert-butylbenzene dianhydride.

Abstract: The invention herein relates to a novel soluble polyimide resin comprising polyalicyclic structures and the process of preparation of the same, wherein aromatic tetracarboxylic dianhydride and novel aromatic diamine having an polyalicyclic group with various structures are used to yield a novel form of a polyimide resin, which has superior heat-resistance, solubility, and transparency.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance and solubility, which is prepared by means of reacting diamine monomers having a novel chemical structure with various types of aromatic carboxilic dianhydrides, in stead of aromatic diamine used for the preparation of the conventional polyimide resin. As a result, the polymers so obtained had the glass transition temperature of 260.degree. C..about.410.degree. C. and showed a increase in solubility in proportion to the increase in a number of the aromatic rings between two phenyl groups.

Abstract: Tough, soluble, aromatic, thermoplastic copolyimides were prepared by reacting 4,4'-oxydiphthalic anhydride, 3,4,3',4'-biphenyltetracarboxylic dianhydride and 3,4'-oxydianiline. Alternatively, these copolyimides may be prepared by reacting 4,4'-oxydiphthalic anhydride with 3,4,3',4'-biphenyltetracarboxylic dianhydride and 3,4'-oxydiisocyanate. Also, the copolyimide may be prepared by reacting the corresponding tetra acid and ester precursors of 4,4'-oxydiphthalic anhydride and 3,4,3',4'-biphenyltetracarboxylic dianhydride with 3,4'-oxydianiline. These copolyimides were found to be soluble in common amide solvents such as N,N'-dimethyl acetamide, N-methylpyrrolidinone, and dimethylformamide allowing them to be applied as the fully imidized copolymer and to be used to prepare a wide range of articles.

Abstract: The invention herein relates to a soluble polyimide resin for a liquid crystal alignment layer and the manufacturing method thereof, wherein a mixture of aliphatic tetracarboxylic acid dianhydrides and aromatic diamine having aliphatic side chains are used to yield a soluble polyimide resin which has superior heat-resistance, solubility, surface hardness, transparency and liquid crystal alignment capacity.The soluble polyimide resin having alkoxy substituents, for a liquid crystal layer, according to the present invention, is manufactured by adding a mixture of dioxotetrahydrofuran 3-methylcyclohexene-1,2-dicarboxylic dianhydride, which is an aliphatic tetracarboxylic acid dianhydride and aromatic tetracarboxylic acid dianhydride to a mixture of aromatic diamine, and said dioxotetrahydrofuran 3-methylcyclohexene- 1,2-dicarboxylic dianhydride is used in the amount of 50 to 99 mol % to the total amount of anhydrides.

Abstract: Fluorinated polymides comprising units of 2,2',5,5',6,6'-hexafluorobiphenyl-3,3',4,4'-tetracarboxylic dianhydride and aromatic diamines.

Abstract: This invention relates the novel diamines, the polyimide oligomers and the polyimides derived therefrom and to the method of preparing the diamines, oligomers and the polyimides. The thermoplastic polyimides derived from the aromatic diamines of this invention are characterized as having a high glass transition temperature, good mechanical properties and improved processability in the manufacture of adhesives, electronic and composite materials for use in the automotive and aerospace industry. The distinction of the novel aromatic diamines of this invention is the 2,2',6,6'-substituted biphenyl radicals which exhibit noncoplanar conformation that enhances the solubility of the diamine as well as the processability of the polyimides, while retaining a realatively high glass transition temperature and improved mechanical properties at useful temperature ranges.

Abstract: The object of the present invention is to provide polyimide composition having such excellent property as low water absorption and low hygroscopic swelling, and a base tape for a TAB carrier tape and a FPC.The another object of the present invention is to provide polyimide composition comprising polyimide consisting of a repeating unit of the general formula (1): ##STR1## The further object of the present invention is to provide a base tape for a TAB carrier tape containing polyimide film made from said polyimide composition as a base film and a FPC containing polyimide film made from said polyimide composition as an insulating material.

Abstract: The invention herein relates to a soluble polyimide resin and the process of preparation of the same, wherein aromatic tetracarboxylic dianhydride and aromatic diamine having an alicyclic group with various structures of substituted alkyl groups are used to yield a novel form of a polyimide resin, which has superior heat-resistance, solubility and transparency.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance and solubility, which is prepared by means of reacting aromatic diamine monomers having a novel chemical structure with various types of aromatic tetracarboxilic acid dianhydrides, in stead of aromatic diamine used for the preparation of the conventional polyimide resin. As a result, the polymers so obtained had the glass transition temperature of 250.degree. C..about.400.degree. C. and showed a increase in solubility in proportion to the increase in volume of the alkyl group.

Abstract: A polyamideimide for optical communications, having a minimum light absorption loss in a near infrared light wavelength range, high thermal stability and excellent film processibility, and a method for preparing the same are provided. The polyamideimide has a higher refractive index than the conventional fluorinated polyamideimide. Thus, when using such polyamideimide as a material for a core of an optical fiber, the selection range on the material for cladding becomes wide. Also the coating property and adhesiveness to a substrate are improved, thereby providing a good film processibility and heat resistance.

Abstract: Novel molten-salt type polyelectrolytes are disclosed which contain as an essential ingredient a molten salt polymer obtained by reacting an imidazolium derivative, such as a 1,3-dialkylimidazolium halide, 1,2,3-trialkylimidazolium halide, 1-vinyl-3-alkylimidazolium halide, or 1-vinyl-2,3-alkylimidazolium halide, with an acid monomer, a poly(vinylsulfonamide), trifluoromethanesulfonimide, or the like. The electrolytes show high ionic conductivity at room temperature and have excellent stability to temperature fluctuations and excellent mechanical properties.

Abstract: The service life of fiber-reinforced polyimide composites in a high temperature oxidative environment is extended by coating with a polyimide coating precursor solution that is synthesized by reacting an aromatic dianhydride with an aromatic diamine in a non-reactive solvent. The reactive solution is heated to a temperature sufficent to reduce its viscosity prior to its use as a coating. Preferably, a mixture of meta-phenylenediamine and para-phenylenediamine is reacted with biphenyldianhydride in n-methyl pyrrolidinone solvent and thereafter heated to between about 50.degree. C. (122.degree. F.) and 150.degree. C. (302.degree. F.) under nitrogen while stirring for a time sufficient to obtain a polyamic acid polyimide precursor coating solution having a Brookfield viscosity of from about 500 to about 5000 cP and a solids content of from about 5 to about 35 weight percent.

Abstract: A photosensitive polyimide, which comprises a copolymer of (A) three diamine compounds mixture consisting of a diaminopolysiloxane, a hydroxyl group-containing diamine or carboxyl group-containing diamine and 1,4-bis[2-(3-aminobenzoyl)ethenyl]benzene with (B) an aromatic tetrocarboxylic acid dianhydride or a dicarboxylic anhydride having a 2,5-dioxotetrahydrofuryl group as one acid anhydride group, is soluble in all-purpose low boiling organic solvents, typically methyl ethyl ketone and provides a negative type photosensitive polyimide, which is developable with an aqueous alkaline solution.

Abstract: An organic polymer compound is synthesized by introducing an electron donor and an electron acceptor into a main polymer chain through chemical bonds in the mixing system at a molecular level. An electroluminescence display device (ELD) which has low driving voltage, various colors and rapid responsive speed is produced by using the organic polymer compound as a luminescent material.The luminescent compound for an electroluminescence display device (ELD) is used as an electroluminescent material of a light emitting diode (LED) and an ELD in a flat panel display and applied to organic material devices field because of low driving voltage, various colors, rapid responsive speed and film processibility.

Abstract: The invention herein relates to a soluble polyimide resin for a liquid crystal alignment layer and the process of preparation of the same, wherein aliphatic tetracarboxylic dianhydride and aromatic diamine having the amide group are used to yield a novel form of a polyimide resin having superior heat-resistance, solubility, transparency, and liquid crystal alignment capacity.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance, solubility, liquid crystal alignment property, and high pretilt angle, which is prepared by means of jointly using the aromatic diamine, used for the preparation of the conventional polyimide resin, and the aromatic diamine having a long alkyl chain with a substituted amide group, and reacting the same with various types of carboxylic dianhydride.

Abstract: A polyamideimide for optical communications, having a minimum optical loss in a near infrared light wavelength range, high thermal resistance and good film processibility, and a method for preparing the same are provided. The polyamideimide is very useful as an optical material in the optical communications field adopting the light of near infrared light wavelength.

Abstract: The invention relates to a silicon-containing polyimide resin comprising (I) 0.1 to 100 mole % of structural units represented by the formula: ##STR1## where Ar.sup.1 is a tetra valent organic group having at least one aromatic ring, R independently represents a monovalent hydrocarbon group free of aliphatic unsaturated bonds, X is selected from an alkyleneoxyalkylene or an alkylene group having 2 or more carbon atoms, Y is an oxygen atom, an alkyleneoxyalkylene group, or an alkylene group having 2 or more carbon atoms, l, m, n are each integers having a value of 1 to 10, p is an integer having a value of 1 to 80, and a is 0 or 1; and (II) 99.9 to 0 mole % of structural units represented by the formula: ##STR2## where Ar.sup.2 is a tetravalent organic group having at least one aromatic ring, and Ar.sup.3 is a divalent organic group having at least one aromatic group.

Abstract: The invention relates to a crosslinkable polymer for use in optics and non-linear optics, which comprises at least one chromophore, characterized in that it has, on at least two of its ends, at least one reactive end group of a different chemical type from the group predominantly used in polymerization and the preparation of a polymer skeleton. Said reactive end group comprises at least one CC, CN, CS, SS or NS double bond and/or triple bond, and/or an epoxy group and/or a thiol group or a derivative of said groups, and the polymerization groups are selected from at least one of the following groups: urethane, ester, amide, imide, ether, carbon-carbon, sulfide, silane and siloxane, urethane and ester groups being particularly preferred. Application in optical and opto-electronic materials and devices.

Abstract: Methods and devices for controlling the oxidation of a hydrocarbon to an acid by regulating the temperature hold-up time, and conversion in consecutive reaction zones. The temperature in the consecutive reaction zones progressively decreases, while the hold-up time increases. Preferably, the conversion also increases. One of the major advantages of the methods and devices of the present invention is that an outstanding balance between productivity and selectivity/yield of the desired acid may be achieved. In this respect high yields and selectivities may be obtained without sacrificing productivity.

Abstract: A new holographic substrate utilizing flexible, optically transparent fluorinated polyimides. Said substrates have extremely low birefringence which results in a high signal to noise ratio in subsequent holograms. Specific examples of said fluorinated polyimides include 6FDA+APB and 6FDA+4BDAF.