Abstract: Disclosed are a polyamic acid having repeating units represented by the formula (1): 1

Abstract: Novel polyimide copolymer, which is a copolymer of isopropylidene-bis-(4-phenyleneoxy-4-phthalic acid)dianhydride and 6-amino-2-(p-aminophenyl)benzimidazole or a copolymer of two kinds of tetracarboxylic acid dianhydrides consisting of isopropylidene-bis-(4-phenyleneoxy-4-phthalic acid)dianhydride and 3,3′,4,4′-benxophenonetetracarboxylic acid dianhydride and 6-amino-2-(p-aminophenyl)benzimidazole, can form a metal laminate by direct lamination with metallic foils. The metal laminate can fully satisfy the peel strength.

Abstract: The present invention provides an optical polyimide compound defined by the following formula in an optical high polymer material: wherein X is Cl, Br, oxo-halide, or fully halogenated alkyl; A is a divalent aromatic or halogenated aromatic moiety; and Z is a tetravalent moiety which may be a partly or fully fluorinated aromatic ring, a partly or fully chlorinated aromatic ring, a partly or fully fluorinated cycloaliphatic group, a partly or fully chlorinated aliphatic group, or combinations thereof connected via hetero atoms.

Abstract: The polyamic acid of the invention can be obtained by the reaction of an acid anhydride component comprising pyromellitic anhydride and 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane with 2,2′-di-substituted-4,4′-diaminobiphenyls as a first aromatic diamine and any aromatic diamine component, as a second aromatic diamine, of 2,2-bis(4-aminophenoxyphenyl)propanes, 1,1-bis(4-(4-aminophenoxy)-3-t-butyl-6-methylphenyl)butane, 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane and &agr;,&agr;′-bis(4-aminophenyl)diisopropylbenzenes in an organic solvent. The polyimide resin of the invention can be obtained by heating such a polyamic acid solution. In the production of a circuit board, by using a photosensitive polyamic acid having a sensitizer incorporated in such a polyamic acid solution, a patterned polyimide resin layer can be provided as an insulation layer on a metal foil.

Abstract: Random, melt-processible copolyimides are disclosed herein. These copolyimides are semicrystalline and exhibit recoverable (semi)crystallinity from their melts. Associated processes, which entail either solution polymerization or melt polymerization, for producing and fabricating these copolyimides into useful articles having a predetermined shape are also disclosed.

Abstract: Random, melt-processible copolyimides are disclosed herein. These copolyimides are semicrystalline and exhibit recoverable (semi)crystallinity from their melts. Associated processes, which entail either solution polymerization or melt polymerization, for producing and fabricating these copolyimides into useful articles having a predetermined shape are also disclosed.

Abstract: An electronically active film comprising a compound of the formula: 1

Abstract: Random, melt-processible copolyimides are disclosed herein. These copolyimides are semicrystalline and exhibit recoverable (semi)crystallinity from their melts. Associated processes, which entail either solution polymerization or melt polymerization, for producing and fabricating these copolyimides into useful articles having a predetermined shape are also disclosed.

Abstract: In a photoconductive element comprising a conductive support, e.g., an electrically conductive film, drum or belt on which a negatively chargeable photoconductive layer is formed, an electrical barrier layer is formed between the support and the photoconductive layer. The barrier layer provides a high energy barrier to the injection of positive charges but transports electrons under an applied electric field. The barrier layer of the invention transports charge by electronic rather than ionic mechanisms and, therefore, is not substantially affected by humidity changes. The barrier layer comprises a polyester-co-imide, polyesterionomer-co-imide or polyamide-co-imide having covalently bonded as repeating units in the polymer chain, aromatic tetracarboxylbisimide groups of the formula: wherein Ar1 and Ar2 represent, respectively, tetravalent and trivalent aromatic groups of 6 to 20 carbon atoms.

Abstract: A method of making a solution of a polyimide from a diamine monomer and a dianhydride monomer is disclosed. A solution or slurry of one of the monomers in a solvent that boils at a temperature between about 80° C. and about 160° C. is prepared. The solution or slurry is heated to a temperature between about 80° C. and about 160° C. and the other monomer is slowly added to the solution or slurry. Polyamic acid that is formed quickly imidizes to form the polyimide.

Abstract: An alignment treating agent for a liquid crystal cell, which comprises a polyimide resin of the formula (I): wherein R1 is a tetravalent organic group constituting a tetracarboxylic acid or its derivative, R2 is a bivalent organic group constituting a diamine, and m is a positive integer, provided that at least 10 mol % of R2 is a bivalent organic group selected from the group consisting of: wherein X is H, OH, an alkyl group, an alkoxy group, a carboxyl group, an acyl group or a halogen atom, said polyimide resin being made insoluble in an organic solvent by coating a precursor solution of said polyimide resin on a substrate, followed by heating.

Abstract: An acid dianhydride, together with a diamine, is heated in an organic polar solvent in the presence of &ggr;-caprolactone or &bgr;-butyrolactone as an acid catalyst to prepare a polyimide having an average molecular weight of 10,000 to 300,000. This production process can realize the production of a polyimide which is soluble in a solvent and has high processability and stability.

Abstract: The invention relates to the use of heterocyclic quaternary polyammonium polymers as protective agent for keratin fibres, to cosmetic compositions using them and to method for treating hair with the aid of these polymers.

Abstract: A graft copolymer is prepared by a process comprising: graft polymerizing a polyamide-forming monomer selected from the group consisting of lactams and &ohgr;-aminocarboxylic acids and an oligocarboxylic acid selected from the group consisting of from 0.015 to about 3 mol. % of dicarboxylic acid and from 0.01 to about 1.2 mol. % of tricarboxylic acid, in each case the stated amounts of oligocarboxylic acid based on a molar amount of lactam, &ohgr;-aminocarboxylic acid or combination thereof, onto from 0.5 to 25% by weight, based on the graft copolymer, of a polyamine having at least 11 nitrogen atoms and a number-average molecular weight Mn of at least 500 g/mol., wherein the amino group concentration in the graft copolymer ranges from 100 to 2500 mmol./kg.

Abstract: A process for production of polyimide powder, which comprises reacting a biphenyltetracarboxlic dianhydride and an aromatic diamine in an amide-based solvent optionally containing a water-soluble ketone, in the presence of an imidazole at 1-100 equivalent percent based on the carboxylic acid content of the polyimide precursor, separating and collecting the produced polyimide precursor powder from a water-soluble ketone solvent containing 3-30 wt % of an amide-based solvent, and heating the polyimide precursor powder to an imidation rate of 90% or greater, as well as polyimide powder obtained thereby, molded bodies of the polyimide powder, and a process for production of the molded bodies.

Abstract: A process for production of polyimide powder, which comprises reacting an aromatic diamine with a partial ester of a biphenyltetracarboxylic dianhydride, which is a partial ester of a biphenyltetracarboxylic dianhydride with a primary alcohol of 1-5 carbon atoms of which at least 30 mole percent is a 2,3,3′,4′-biphenyltetracarboxylic acid component, in the presence of the primary alcohol, separating out and collecting the resulting solid polyimide precursor and heating for dehydrating ring closure, polyimide powder obtained thereby, molded bodies of the polyimide powder, and a process for production of the molded bodies.

Abstract: The present invention relates to compounds containing modified hydrazide groups and corresponding to formula I wherein R represents the residue obtained by removing the isocyanate groups from a monomeric polyisocyanate, a polyisocyanate adduct or an NCO prepolymer, X represents OR′ or NHR′ and R′ represents a group which is inert to isocyanate groups under the conditions used to form the compound of formula I, R″ represents a divalent, linear or branched aliphatic group containing 2 to 10 carbon atoms, provided that there are at least two carbons between the oxygen atoms wherein the aliphatic group may optionally be substituted by heteroatoms to form ether or ester groups, and n is 2 to 6.

Abstract: A polyimide resin composition comprising a polyimide resin (A) and at least one 1H-tetrazole (B) selected from the group consisting of 1H-tetrazole, 5,5′-bis-1H-tetrazole, and derivatives thereof, and having an excellent rust preventing effect on copper and copper alloys.

Abstract: A composition of and method for making high performance imide resins that are processable by resin transfer molding (RTM) and resin infusion (RI) techniques were developed. Materials with a combination of properties, making them particularly useful for the fabrication of composite parts via RTM and/or RI processes, were prepared, characterized and fabricated into moldings and carbon fiber reinforced composites and their mechanical properties were determined. These materials are particularly useful for the fabrication of structural composite components for aerospace applications. The method for making high performance resins for RTM and RI processes is a multi-faceted approach. It involves the preparation of a mixture of products from a combination of aromatic diamines and aromatic dianhydrides at relatively low calculated molecular weights (i.e. high stoichiometric offsets) and endcapping with latent reactive groups.

Abstract: A polyimide resin composition comprising a polyimide resin (A) and at least one 1H-tetrazole (B) selected from the group consisting of 1H-tetrazole, 5,5′-bis-1H-tetrazole, and derivatives thereof, and having an excellent rust preventing effect on copper and copper alloys.

Abstract: A flexible printed board, in which a polyimide resulting from the imidation of a polyamic acid obtained by the addition polymerization of diamines and acid dianhydrides is formed as an insulating layer on a metal foil, is characterized in that the diamines include specific imidazolyl-diaminoazines represented by the formula 1; (where A is an imidazolyl group; R1 is an alkylene group; m is 0 or 1; R2 is an alkyl group; n is 0, 1, or 2; R3 and R4 are alkylene groups; p and q are each 0 or 1; and B is an azine residue, diazine residue, or triazine residue).

Abstract: A polyimide film having sufficiently excellent characteristics such as a sufficiently high elastic modulus, a low water absorption, a small coefficient of moisture-absorption expansion, a small coefficient of linear expansion and a high dimensional stability; and various electric/electronic equipment bases with the use of the polyimide film. A polyimide film having a tensile elastic modulus of 700 kg/mm2 or less and a coefficient of moisture-absorption expansion of 20 ppm or less and containing a specific repeating unit as an essential repeating unit is synthesized. Then various electric/electronic equipment bases such as a laminate for flexible print connection boards are produced by using the polyimide film.

Abstract: Phenylethynyl containing reactive additives were prepared from aromatic diamines containing phenylethynyl groups and various ratios of phthalic anhydride and 4-phenylethynylphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pyrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

Abstract: Novel polyimides substituted by a substituent having an alkyl or fluoroalkyl group and having reduced water absorption; a process for producing these novel polyimides; and novel acid dianhydrides to be used in the production thereof. A polyimide containing a structure represented by the following general formula (I): wherein X1 represents a tetravalent organic group having a substituent —R1AR2 (wherein A represents a divalent linkage group; R1 represents a single bond or a C1-3 alkylene group; and R2 represents a C1-25 alkyl group or a fluoroalkyl group); and Y represents a divalent organic group.

Abstract: A polyimide silicone resin which contains not more than 300 ppm of a cyclic siloxane oligomer having 10 or less silicon atoms, has a glass transition point of 250° C. or below and is soluble in an organic solvent. This polyimide silicone resin is produced using a diamine containing a diaminosiloxane containing not more than 300 ppm of the cyclic siloxane oligomer. Also disclosed is a polyimide silicone resin composition including 50 to 99% by mass of the polyimide silicone resin and 1 to 50% by mass of an epoxy compound. The polyimide silicone resin has been made to less contain the cyclic siloxane oligomers causative of trouble in electrical contacts, and promises a good adhesiveness or bond strength to substrates and a high reliability.

Abstract: In a photoconductive element comprising a conductive support, e.g., an electrically conductive film, drum or belt on which a negatively chargeable photoconductive layer is formed, an electrical barrier layer is formed between the support and the photoconductive layer. The barrier layer provides a high energy barrier to the injection of positive charges but transports electrons under an applied electric field. The barrier layer of the invention transports charge by electronic rather than ionic mechanisms and, therefore, is not substantially affected by humidity changes.

Abstract: A primary object of the invention is to provide a production technology for functional polyamic acid microfine particles and functional polyimide microfine particles by which the particle shape, size and size distribution can be freely controlled. The invention is concerned with a process for synthesizing polyamic acid particles having functional groups at least on the surface from a tetracarboxylic anhydride and a diamine compound characterized by its comprising (a) a first step which comprises providing a tetracarboxylic anhydride and a diamine compound at least one of which has functional groups and preparing a first solution containing the tetracarboxylic anhydride and a second solution containing the diamine compound and (b) a second step which comprises mixing the first and second solutions under ultrasonic agitation to thereby precipitate polyamic acid microfine particles from the mixed solution.

Abstract: A polyimide film, which is produced from polyamide acid prepared through the reaction of p-phenylenebis(trimellitic acid monoester anhydride), oxydiphthalic acid dianhydride, p-phenylenediamine, and 4,4′-diaminodiphenylether in an organic solvent, and which has a high elastic modulus, a high elongation, a low coefficient of linear expansion which is not quite different from that of copper, and a low coefficient of hygroscopic expansion.

Abstract: A process for the preparation of an oligomeric polyimide comprises: mixing a tetracarboxylic acid, a dianhydride, a partially hydrolysed dianhydride or a mixture thereof with a diamine in a reaction medium comprising greater than 80% by weight water, and heating mixture in said reaction medium at a temperature above 100° C. for a time sufficient to form said oligomeric polyimide.

Abstract: A method for preparing polyamic acid and polyimide of three-dimensional molecular structure such that these polymers are superior in adhesive strength and high-temperature stability while maintaining their inherent thermal resistance and mechanical properties, and thus can be effectively used as an adhesive material for high temperature adhesive tapes suitable for semiconductor assembly.

Abstract: A polyimide for optical communications, which is expressed by the formula (1) where R1 and R2 are independently selected from the group consisting of CF3, CCl3, unsubstituted aromatic ring group and halogenerated aromatic ring group; R3 and R4 are independently selected from the group consisting of Cl, F, I, Br, CF3, CCl3, unsubstituted aromatic ring group and halogenated aromatic ring group; and n is an integer from 1 to 39. The polyimides have a superior heat resistance, and can avoid the increase in optical absorption loss due to a refractive index increase and deterioration of adhesive and coating properties due to weak surface tension of a polyimide film. In addition, use of the polyimides as a material for a core layer of optical waveguides can expand the selection range of material for the cladding layer of the optical waveguide.

Abstract: The present invention provides a liquid crystal display element having an adequate pre-tilt angle for preventing the reverse domain, as well as excellent electrical properties by preparation of the polyamic acid composition for the liquid crystal display element which comprises a polyamic acid A that excels in electrical properties and a polyamic acid B that has side chains, mixed in the ratio A/B of 50/50 to 95/5 (by weight).

Abstract: A polyimide resin composition comprising a polyimide resin (A) and at least one 1H-tetrazole (B) selected from the group consisting of 1H-tetrazole, 5,5′-bis-1H-tetrazole, and derivatives thereof, and having an excellent rust preventing effect on copper and copper alloys.

Abstract: A polymide useful as an adhesive for semiconductor assemblies having excellent thermal resistance and adhesive strength at high temperatures.

Abstract: Polyimides and the process for preparing polyimides having improved thermal-oxidative stability derived from the polymerization of effective amounts of one or more of the polyamines such as the aromatic diamines, one or more of the tetracarboxylic dianhydrides and a novel dicarboxylic endcap having a formula selected from the group consisting of: wherein R1 is either a radical where R is either hydrogen or an alkyl radical of 1 to 4 carbons, R2 is either OH, NH2, F, or Cl radical, R3 is either H, OH, NH2, F, Cl or an alkylene radical, R4 is either an alkyl, aryl, alkoxy, aryloxy, nitro, F, or Cl radical, and R5 is either H, alkyl, aryl, alkoxy, aryloxy, nitro, F, or Cl radical. The polyimides are useful particularly in the preparation of prepregs and PMR composites.

Abstract: A polyimide for optical communications, which is expressed by the formula (1), a method of preparing the same, and a method of forming multiple polyimide films using the polyimide, wherein the formula (1) is given by X1, X2, X3, A1, A2, B1, B2, B3, D1, D2, E1, E2, Y1, Y2, Y3, Y4, Y5, Y6, Y7, and Y8, are independently selected from the group consisting of hydrogen atom, halogen atom, alkyl group, halogenated alkyl group, aryl group and halogenated aryl group; Z is a simple chemical bond or selected from the group consisting of —O—, —CO—, —SO3—, —S—, —(T)m—, —(OT)m— and —(OTO)m—, wherein T is alkylene or arylene group substituted by at least one of halogen atom and halogenated alkyl group and m is an integer from 1 to 10; and n is an integer from 1 to 39.

Abstract: The present invention provides a novel polyimide composition which includes a cinnamoyl group or a derived cinnamoyl group and has photo-reactivity and heat-reactivity inherent to the cinnamoyl group. Further, a novel diamine and an acid dianhydride according to the present invention are materials mainly used for preparing a novel polyimide composition having the cinnamoyl group or the derived cinnamoyl group in a main chain or a side chain.

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: Terminal-modified imide oligomers with an inherent viscosity of 0.05-1 obtained by reacting 2,3,3′,4′-biphenyltetracarboxylic dianhydride, an aromatic diamine compound and 4-(2-phenylethynyl)phthalic anhydride, and their cured products. There are provided highly practical terminal-modified imide oligomers and their cured products, which cured products have satisfactory heat resistance and mechanical properties.

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

Abstract: A polyimide film of birefringence less than 0.01 is formed by drawing a copolymerized polyimide comprising a block component and a random component which are molecularly bonded, wherein the block component of copolymerized polyimide comprises an aromatic diamine compound having a rigid structure and an aromatic tetracarboxylic acid compound and wherein the random component of copolymerized polyimide comprises an aromatic diamine compound having a flexible structure and at least two aromatic tetracarboxylic acid components. The resulting polyimide film has high elasticity, a low thermal expansion equivalent to that of metal and low water absorbing properties. A method for its manufacture and a metal laminated plate having improved curl properties in which the polyimide is used as the base material are also disclosed.

Abstract: Polyimides and the process for preparing polyimides having improved thermal-oxidative stability derived from the polymerization of effective amounts of one or more of the polyamines such as the aromatic diamines, one or more of the tetracarboxylic dianhydrides and a novel dicarboxylic endcap having a formula selected from the group consisting of: wherein R1 is either a radical where R is either hydrogen or an alkyl radical of 1 to 4 carbons, R2 is either OH, NH2, F, or Cl radical, R3 is either H, OH, NH2, F, Cl or an alkylene radical, R4 is either an alkyl, aryl, alkoxy, aryloxy, nitro, F, or Cl radical, and R5 is either H, alkyl, aryl, alkoxy, aryloxy, nitro, F, or Cl radical. The polyimides are useful particularly in the preparation of prepregs and PMR composites.

Abstract: The present invention relates to a treating agent for liquid crystal alignment, which is an agent for liquid crystal alignment to be used for a method in which polarized ultraviolet rays or electron rays are irradiated on a polymer thin film formed on a substrate in a predetermined direction relative to the substrate plane, and said substrate is used for aligning liquid crystal without rubbing treatment, wherein said agent for liquid crystal alignment contains a polymer compound having photochemically reactive groups in the polymer main chain and a glass transition temperature of at least 200° C.

Abstract: The present invention provides a process for preparing an optical alignment layer for aligning liquid crystals and liquid crystal displays comprising exposing polyimide layers with polarized light. The invention further describes optical alignment layers, liquid crystal displays incorporating optical alignment layers and novel polymer compositions within the class of polyimide, polyamic acids and esters thereof.

Abstract: Disclosed is a solvent soluble polyimide and a method for making thereof, which characterizes by producing a solvent soluble polyimide with low electric conductivity through the polymerization of an anhydride and a diamine under the condition with or without catalyst.

Abstract: Addition-cured polyimides that contain the reaction product of an aromatic triamine or trianhydride analogue thereof, a reactive end group such as 5-norbornene-2, 3-dicarboxylic acid, ester derivatives of 5-norbornene-2,3-dicarboxylic acid, anhydride derivatives of 5-norbornene-2,3-dicarboxylic acid, or 4-phenylethynylphthalic anhydride, an aromatic diamine, and a dialkyl ester of an aromatic tetracarboxylic acid. The resultant starlike polyimides exhibit lower melt flow viscosity than its linear counterparts, providing for improved processability of the polyimide. Also disclosed are methods for the synthesis of these polyimides as well as composite structures formed using these polyimides.

Abstract: A polyamic acid varnish composition, which is composed of a polyamic acid obtained by the addition polymerization of an diamine and an aromatic acid dianhydride, contains as an additive a specific imidazolyl-diaminoazine.

Abstract: A method for preparing polyamic acid and polyimide, which is suitable for use in adhesives or adhesive tapes for electronic parts. The polymers have such three-dimensional molecular structures that a significant improvement can be brought about in solvent solubility, thermal resistance, mechanical properties, and adhesive properties onto various substrates. The polyamic acid is prepared by reacting at least one tetracarboxylic dianhydride, at least one aromatic diamine, at least one diamine with a siloxane structure, represented by the following general formula I, and at least one polyamino compound represented by the following general formula II or III. The polyamic acid is converted into polyimide through thermal or chemical imidization.

Abstract: An aromatic polycarbodiimide comprising a structure represented by the following formula (1) has excellent low moisture resistance, heat resistance and a low dielectric constant: wherein Q is one selected from the group consisting of —CH2—, m is 0 or 1, A is a divalent organic group having 4 or less carbon atoms, Ph is a phenyl group, X's are a hydrogen atom when Q is and the same or different halogen atoms when Q is —CH2—, and n is an integer of 2 to 300.

Abstract: The invention relates to sulphonated polyimides, notably of formula (I) The invention also relates to an ion exchange membrane that includes such a polyimide and a fuel cell that includes such a membrane. The membranes of the invention have excellent durability and low cost and the fuel cells can be used, in particular, in electric vehicles.