Abstract: The present invention provides a liquid crystal-aligning agent including, as the resin component, a polyimide precursor containing a chemical structure represented by the following formula (1): The present invention further provides a liquid crystal-aligning agent including, the above polyimide precursor and a polyimide precursor represented by the following general formula (2): (wherein Y is a tetravalent aliphatic group, Z is a bivalent aromatic group, and R is H or an alkyl group).

Abstract: Essentially colorless, transparent polyimide coatings and films prepared by combining aromatic dianhydrides with para-substituted aromatic diamines are provided. The polyimide coatings and films are produced by a process whereby the dianhydride and diamine monomer components are reacted at temperatures of greater than 80° C.

Abstract: Process for producing highly stretchable, amorphous anisotropic melt-forming polymers having recurring units derived from p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, at least one aromatic diacid and at least one aromatic diol and/or hydroxyamine component, at least a portion of which is 4,4′-biphenol, which process comprises incorporating into such polymers recurring units derived from one or more aromatic monomers that provide the polymers with selected meta-linkages wherein each of said recurring units is present in the polymer in specific amounts.

Abstract: The invention relates to a process for preparing hydroxyl- and carboxyl-containing polyesterimide resins, comprising as monomeric components: (A) imide-forming compounds having at least two primary amino groups and/or at least two isocyanate groups or imide-forming compounds having at least one primary amino group and/or at least one isocyanate group and at least one further functional group selected from hydroxyl, carboxyl and/or carboxylic anhydride, (B) polycarboxylic acids and/or their anhydrides and/or their esters and (C) polyols, characterized in that (I) component (A) is reacted with part of component (B) to form a polyimide, (II) the polyimide obtained in accordance with stage (I) is reacted with component (C) to form a polyesterimide, and finally (III) the polyesterimide obtained in accordance with stage (II) is reacted with the remaining part of component (B) to form the Also embraced by the invention is the use of the polyesterimides prepared by the process according to the invention as bi

Abstract: Heat resistant polybenzoxazole resins useful as layer insulation films and protective films for semiconductor, layer insulation films for multilayer circuits, cover coats for flexible copper-clad sheets, solder resist films, liquid crystal-aligned films and the like. These resins have excellent thermal, electrical, physical and mechanical characteristics. Polybenzoxazole precursors are provided, represented by the general formula (A), and are used to obtain polybenzoxazole resins, represented by the general formula (D). In the formulas (A) and (D), n denotes an integer from 2-1000, and X denotes a structure having a formula selected from structures indicated at (B). In the formulas at (B), Y denotes a structure having a formula selected from those indicated at (C), and the hydrogen atom(s) on the benzene ring in these structures are optionally substituted.

Abstract: The present invention relates to the synthesis of new type of diamine monomer, 1,3-bis(4-amonophenoxy)naphthalene, and with such a compound to produce a series of aromatic polymers, including polyamide, polyimide, copoly(amide-imide)s, etc., such polymers having excellent resistance to heat and mechanical properties.

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: 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: A biaxially oriented film made from a wholly aromatic polyamide produced by an acid chloride process, which contains at least one member of inorganic particles having an average particle diameter of 5 to 2,000 nm and selected from the group consisting of hydroxides, carbonates and bicarbonates of metals of groups Ia and IIa of the periodic table. The inorganic particles is derived from inorganic particles which are added as a neutralizing agent to a reaction system to neutralize hydrogen chloride by-produced by the acid chloride reaction and its content corresponds to an excess portion added to the reaction system over the amount required for neutralizing the hydrogen chloride stoichiometrically. The film is useful as a base film for a magnetic recording medium, such as a coated, a multi-layer coated, or a thin metal film high-density magnetic recording medium.

Abstract: The invention herein relates to a process of preparing a novel polyimide foam having superior heat-resistance, flame retardancy, homogeneous size and distribution of cells, and low density, wherein a polyimide precursor in a granular form is prepared by means of using heterocyclic amine as catalyst and then foaming. According to the present invention, the preparing process of a polyimide foam comprises reacting aromatic carboxylic acid or the anhydrides thereof with an excess of aliphatic univalent alcohol to yield an aromatic ester solution. To the aromatic ester solution, divalent amines or the mixture thereof were added in the equivalent amount of said carboxylic acid or the anhydrides thereof in addition to a catalyst and surfactant to yield a polyimide. Then, the precursor in a granular form mixture was imidized while foaming by means of pre-heating and then heating in a microwave oven, after which was cured at a high temperature.

Abstract: A method for producing polybenzazole in the presence of iron(II) ion. The polybenzazole obtained by this method can be formed into a highly strong fiber having a high elastic modulus and a heat resistant film. The method enables economical production of polybenzazole having fine tone and high polymerization degree.

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: Rod-like aromatic heterocyclic polymers having repeating units of the formula --(--Q--Ar--).sub.m --(--Q--Ph--).sub.n)-- where Q is ##STR1## X is --O--, --S--, or --NH--; m is 0.05 to 1.0; n is 1.0-m; Ph is 1,4-phenylene; Ar is ##STR2## R.sub.1 and R.sub.2 are the same and are either H or CH.sub.3 ; and R.sub.3 and R.sub.4 are CH.sub.3.

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: Process for producing highly stretchable, amorphous anisotropic melt-forming polymers having recurring units derived from p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, at least one aromatic diacid and an aromatic diol and/or hydroxyamine component, at least a portion of which is 4,4'-biphenol, which comprises incorporating into such polymers recurring units derived from resorcinol and at least one additional monomer that provides the resulting polymer with selected meta linkages, wherein each of said recurring units is present in the polymer in specified amounts.

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: 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: This invention relates in general to the formation of thick films having a biaxial molecular orientation. Such films are prepared in accordance with the present invention from rod-like extended chain aromatic-heterocyclic ordered polymers. Such films have high tensile strength, modulus, and environmental resistance characteristics. A preferred ordered polymer for use in the present invention is poly (para-phenylenebenzo bisthiazole), (PBT), a compound having the structure: ##STR1## The present invention is also directed to methods and apparatus suitable for producing biaxially oriented films, coatings, and like materials from ordered polymers, preferably PBT.

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: 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: 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: 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: 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: Electronic parts and a process for manufacturing the electronic parts are provided. The electronic parts comprise an electric insulating material exhibiting a high heat resistance and low dielectric constant as a structural component. The electric insulating material is formed of a polyimide containing a recurring unit represented by the following general formula (1).

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: A liquid-crystalline resin composition comprising 100 parts by weight of a semi-aromatic liquid-crystalline polyester and/or a semi-aromatic liquid-crystalline polyester-amide, from 0.001 to 5 parts by weight of at least one or more compounds selected from phosphorous acid, hypophosphorous acid and their salts, and from 0.01 to 10 parts by weight of red phosphorus has good flame retardancy, low anisotropy, good heat resistance and good hydrolysis resistance, and is useful as engineering plastic.

Abstract: A thermoplastic resin composition containing a polyetherimide resin, a siloxane-polyetherimide copolymer and a branched polycarbonate resin exhibits exhibit high heat distortion temperature, improved room temperature impact properties and improved impact strength and ductility at low temperatures.

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: 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: A polymer system having repeating units of the formula: ##STR1## wherein A is --H or --OH, x has a value of 0.5 to 1.0 and y has a value of 1.0-x, exhibits a high glass transition temperature (T.sub.g) and a low dielectric constant. The polymer system is useful in the area of microelectronic packaging.

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: 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: A bis(trisubstitutedtrimellitic anhydride) derivative and a polyesterimide for optical communications, the polyesterimide being formed therefrom. The polyesterimide has a high refractive index, so that when using such polyesterimide as a material for a core of an optical fiber, the range of materials that can be selected for the cladding becomes wide. Also, a coating property and adhesion to a substrate are improved, thereby providing a good film forming property and thermal stability. Also, because the polyesterimide can minimize optical loss at a near infrared wavelength range, the polyesterimide is very useful as an optical material in the optical communications field adopting the light of near infrared wavelength.

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: 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: 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 thermoplastic resin composition containing a polyetherimide resin, a siloxane-polyetherimide copolymer and a branched polycarbonate resin exhibits exhibit high heat distortion temperature, improved room temperature impact properties and improved impact strength and ductility at low temperatures.