Abstract: The invention relates to a PMR type resin which comprises a mixture of:(a) nadic acid of Formula (Ia) or a derivative thereof ##STR1## (b) a diaminobisimide of Formula (Ib) ##STR2## (c) an aromatic tetracarboxylic acid of Formula (Ic) or a derivative thereof ##STR3## the components (a), (b) and (c) being present in the approximate molar proportions of 2:n:n-1 respectively.

Abstract: Novel thermoset polyimide and composite materials comprising the thermoset polyimides and a fibrous reinforcement are prepared according to this invention. The thermoset polyimides are obtained by heat-treating a linear polyamic acid or a linear polyimide prepared by using 4,4'-bis(3-aminophenoxy)biphenyl and pyromellitic dianhydride as essential monomers or by adding 4,4'-diaminodiphenyl ether or 3,3',4,4'-biphenyltetracarboxylic dianhydride to the essential monomers and by end-capping the molecular chain end with an aromatic dicarboxylic anhydride having a carbon-carbon triple bond. The thermoset polyimides have essential excellent properties of thermoplastic polyimide and additionally has enhanced heat resistance and improved mechanical properties. The thermoset polyimide can be used to provide various kinds of composite materials for aircraft matrices, electric and electronic appliances and others.

Abstract: Novel polyimides which are soluble in various organic solvents and excellent in thermal resistance, processability are disclosed. The polyimides comprise repeating units represented by the following formula (1) and/or (2) and having a number average molecular weight of 4,000-200,000. ##STR1## wherein Ar is a divalent group represented by the following formula (2) or (3): ##STR2## wherein Y is --O--, --CO--, --S--, --SO.sub.2 -- or --C(CH.sub.3).sub.2 --, ##STR3## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each a C.sub.1-4 alkyl group or a C.sub.1-4 alkoxy group, Ra is a divalent group having 2-6 benzene rings, X.sup.1 represents NH, NR (wherein R is a C.sub.1-4 alkyl group or a C.sub.1-4 alkoxy group) or S, Rb is C.sub.2-20 alkylene group, ether group or dimethylsiloxane group, and X.sub.2 represents NH, NR (wherein R is a C.sub.1-4 alkyl group or a C.sub.

Abstract: A poly(imide amic ester) having repeating unit of formula (I) and a process for the preparation thereof are provided, wherein formula (I) has the structure ##STR1## wherein Ar is, ##STR2## Ar' is, ##STR3## Ar" is ##STR4## R is selected from the group consisting of CH.sub.3, CH.sub.2 CH.sub.3, CH(CH.sub.3).sub.2, CH.sub.2 CH.sub.2 CH.sub.3, CH.sub.2 (CH(CH.sub.3).sub.2 and C(CH.sub.3).sub.3. Further, processes for the preparation of polyimide, polyimide film and polyimide fiber using the above poly(imide amic ester) are provided.

Abstract: The invention relates to a liquid crystal orientation film having a specific polymer, the main chain of the polymer formed of urea bonds and imide bonds, and a liquid crystal display element incorporating the film. The liquid crystal orientation film does not require high temperature heat treatment when prepared, allowing treatment below about 150.degree. C. Hence, the production of a liquid crystal display element using the liquid crystal orientation film is simplified. Furthermore, other element materials are protected, and the substrate used can be a plastic substrate lower in heat resistance than glass. Moreover, the liquid crystal orientation film is excellent in such properties as liquid crystal orienting capability, heat resistance, transparency, strength and adhesion to the substrate, and has an especially large and stable pre-tilt angle.

Abstract: A polyimide precursor composition which is produced by (i) providing a polyamide acid solution obtained by reacting an aromatic tetracarboxylic acid component and a diamine component in the presence of an oxygen-containing solvent and (ii) subjecting said polyamide acid solution to heat treatment. The polyimide precursor composition exhibits a desirable apparent viscosity and a desirable thixotropic property and it excels in film forming ability, and because of this, it enables the formation a high quality relief pattern film with no defect and which excels in form retention by way of the screen printing.

Abstract: A polyimide alignment film based on pyromellitic dianhydride and a 2,2'-bis(perfluoroalkoxy)benzidine, as major components, for use in liquid crystal display devices.

Abstract: The invention provides novel thermoplastic polyimide featuring solid adhesive property under low temperature, low hygroscopic coefficient, and solid resistivity to radioactive rays. The invention also provides novel polyamide acid which is substantially precursor of the thermoplastic polyimide, and also provides novel thermally fusible laminated film for covering conductive wires, featuring solid adhesive property under low temperature, solid resistivity to radioactive rays, and distinct suitability for covering superconductive wires in particular.The novel thermoplastic polyimide is represented by general formula (1) corresponding to the chemical structure shown below; ##STR1## wherein, Ar.sub.1, Ar.sub.2, Ar.sub.4, and Ar.sub.6, respectively designate divalent organic radical, whereas Ar.sub.3 and Ar.sub.

Abstract: A diaminobenzene derivative of the formula (I): ##STR1## wherein each of P and Q which may be the same or different from each other, is a single bond, or a bivalent organic group selected from the group consisting of --O--, --COO-- and --CONH--, R.sub.1 is a C.sub.2-22 straight chain alkylene group, and R.sub.2 is a cyclic group selected from the group consisting of an aromatic ring, an aliphatic ring, a heterocyclic ring and substituted forms of such rings.

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. ##STR1## wherein X is --SO.sub.2 -- or --C(.dbd.O)--OCH.sub.2 CH.sub.2 O--C(.dbd.O)--, and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

Abstract: We achieve solvent resistance and extended use life for advanced polyimides by including at least some solvent-resistant linkages in the backbone in place of phenoxyphenyl sulfone linkages and using diPEPA or PEPA crosslinking end caps.

Abstract: Polyimide copolymers were prepared by reacting different ratios of 3,4'-oxydianiline (ODA) and 1,3-bis(3-aminophenoxy)benzene (APB) with 3,3',4,4'-biphenylcarboxylic dianhydride (BPDA), and terminating with an effective amount of a reactive endcapper. The reactive endcappers employed include 4-phenylethynyl phthalic anhydride (PEPA), 3-aminophenoxy-4'-phenylethynylbenzophenone (3-APEB), maleic anhydride (MA) and nadic anhydride (5-norbornene-2,3-dicarboxylic anhydride) (NA). Within a relatively narrow ratio of diamines, from .sup..about. 50% ODA/50% APB to .sup..about. 95% ODA/5% APB, the copolyimides prepared with BPDA and terminated with reactive endgroups have a unique combination of properties that make them very attractive for a number of applications. This unique combination of properties includes low pressure processing (200 psi and below), long term melt stability (several hours at 300.degree. C.

Abstract: A process for preparing a tough, soluble, aromatic, thermoplastic copolyimide is provided. The process comprises the steps of (a) providing 4,4'-oxydiphthalic anhydride to 3,4,3',4'-biphenyltetracarboxylic dianhydride at a mole ratio ranging from about 25 mole percent to 75 mole percent to 75 mole percent to about 25 mole percent; (b) adding 3,4'-oxydianiline to form a mixture; c) adding a polar aprotic or polar protic solvent to the mixture to form a solution having a percentage of solids capable of maintaining polymer solubility; (d) stirring the solution to allow it to react; (e) adding an azeotropic solvent to the solution and heating to remove water; (f) cooling the solution of step (e) to room temperature and recovering the tough, soluble, aromatic, thermoplastic copolyimide.

Abstract: Polyamide esters which can be prepared from tetracarboxylic dianhydrides and can be converted into polyimides by alcohol cleavage with cyclization, characterized in that the radicals OR of the ester groups --COOR which are substituted during the polyimide formation are alkoxy radicals having 2 to 5 C atoms which are monosubstituted or polysubstituted by fluorine.Polyimides prepared therefrom are suitable as orientation layers in liquid-crystal display elements and in optical wave guides.

Abstract: A thermoplastic polyimide film comprising a thermoplastic polyimide polymer, a polyimide laminate, respectively being suited for use as cover-lay adhesive agent and a cover-lay film capable of exerting distinguished thermal resistant property, processability and adhesion property useful for the manufacture of flexible printed circuit boards, and yet, suited for use as the adhesive-agent layers of flexible copper-coated laminates and bilateral adhesive sheets; and a method of manufacturing the polyimide laminate. The thermoplastic polyimide polymer represented by the general formula (1) specified below: ##STR1## wherein Ar.sub.1, Ar.sub.2, Ar.sub.4 and Ar.sub.6, represents divalent organic radical, whereas Ar.sub.3 and Ar.sub.5 represent quadrivalent organic radical, wherein l, m amd n designate positive integer of 0 to 15, wherein the sum of 1 and m is 1 or more than 1, and wherein t designates positive integer of 1 or more than 1.

Abstract: Wholly aromatic polyamides and their shaped articles containing at least 85 mole percent of repeat units of m-phenylene isophthalamide: ##STR1## and repeat units of selected aromatic diamines and diacid chlorides exhibit improved flame resistance while retaining good thermal stability.

Abstract: The invention provides a method of preparing a polyimide by reacting together a dianhydride and a diisocyanate or equivalent, the polyimide having repeating units of the general formula (I): ##STR1## in which D is a group comprising one or more aromatic rings, to which the imide carbon atoms are directly bonded, andE is a group comprising one or more cycloaliphatic or aromatic rings, to which the imide nitrogen atoms are bonded directly or via an aliphatic group, provided that the imide nitrogen atoms are not bonded directly to an aromatic ring. Such polyimide is colourless or of low colour.

Abstract: Polyamic acids and corresponding polyimides are prepared by reacting polyfunctional amines, aromatic polyfunctional anhydrides or esters thereof, and allyl-nadic anhydride end capping agents, the resulting products exhibiting excellent properties and being suitable for the preparation of prepregs, composites, adhesives, coatings, and the like.

Abstract: A liquid crystal aligning agent comprising a polyamic acid containing an aliphatic and/or alicyclic hydrocarbon group and a polyimide containing an aliphatic and/or alicyclic hydrocarbon group; and a liquid crystal display device using the liquid crystal aligning agent. This liquid crystal aligning agent gives a liquid crystal aligning film which has good liquid crystal aligning property and in which pretilt angle can be changed by radiation with a small energy and which is suitable for domain-divided alignment type liquid crystal display having a wide view angle.

Abstract: A rigid-rod aromatic polyimide having repeating units of the formula: ##STR1##

Abstract: A liquid crystal alignment film made of a polyimide which has, on its side chain, a benzene or biphenyl ring substituted by a monovalent substituent having a positive value as the .sigma.p value under Hammett's rule.

Abstract: Controlled molecular weight imide oligomers and co-oligomers containing pendent phenylethynyl groups (PEPIs) and endcapped with nonreactive or phenylethynyl groups have been prepared by the cyclodehydration of the precursor amide acid oligomers or co-oligomers containing pendent phenylethynyl groups and endcapped with nonreactive or phenylethynyl groups. The amine terminated amide acid oligomers or co-oligomers are prepared from the reaction of dianhydride(s) with an excess of diamine(s) and diamine containing pendent phenylethynyl groups and subsequently endcapped with a phenylethynyl phthalic anhydride or monofunctional anhydride. The anhydride terminated amide acid oligomers and co-oligomers are prepared from the reaction of diamine(s) and diamine containing pendent phenylethynyl group(s) with an excess of dianhydride(s) and subsequently endcapped with a phenylethynyl amine or monofunctional amine. The polymerizations are carried out in polar aprotic solvents such as under nitrogen at room temperature.

Abstract: Polyamic acids and corresponding polyimides are prepared by reacting phenylindane diamines, aromatic polyfunctional anhydrides or esters thereof, and nadic anhydride or allylnadic anhydride end capping agents, the resulting products exhibiting excellent properties and being suitable for the preparation of prepregs, composites, adhesives, coatings, and the like.

Abstract: A class of rigid rod and latter polymers having light emitting capability is provided. Included in this class of polymers are those having novel repeating structural units. These rigid rod and ladder polymers are employed in light emitting diodes.

Abstract: An alternating copolymer comprising a repeating unit of the formula:--Z--(X-Y).sub.n -- (I)wherein n is at least 2, X is O, S, Se or Te, and Y and Z are independently an aromatic or substituted aromatic group, and at least one other repeating unit, which is useful as a photosensitive material used in a spatial light modulator.

Abstract: The present invention is directed to an exciplex formed from a .pi.-conjugated polymer and an electron donor or acceptor component. The present invention also relates to assemblies comprising said exciplex, their use in optoelectrical devices and method of enhancing optoelectrical properties of .pi.-conjugated polymers by forming said exciplex.

Abstract: The present invention relates to solutions which can be directly shaped in anhydrous dimethylalkyleneurea, based on a polyimide obtained from an aromatic dianhydride and an aromatic diisocyanate.It also relates to the process for the production of the above solutions, as well as to a process for spinning these solutions and to the yarns and fibres thus obtained.

Abstract: The invention relates to a polyamide-imide containing recurring units according to the formula ##STR1## where Y is an arylene group, andR and R' are alkylene groups, in which at least 50 mole % of R and/or R' is a butylene group.The polyamide-imides are semi-crystalline.They are suitable for injection moulding applications, structural moulded parts, films, coatings and fibres. They can preferably be used in fields of application where temperatures above 200.degree. C. occur.

Abstract: A heat-resistant adhesive film, an adhesion structure obtained using the same, and an adhesion method using the same are disclosed, the film comprising a polyisoimide resin containing at least 40 mol % of an isoimide unit represented by formula (I): ##STR1## wherein R.sub.1 represents a tetravalent aromatic or aliphatic residue; R.sub.2 represents a divalent aromatic or aliphatic residue; and the arrow represents a bond replaceable on isomerization, in the molecule thereof. The isoimide unit of the polyisoimide resin is easily converted to an imide unit on heating, e.g., hot pressing with an adherend, to provide a cover-lay film or a single-sided or double-sided base for printed circuit boards having excellent adhesion, heat resistance, dimensional precision, and workability.

Abstract: A polyimide precursor having a molecular structure obtained by polymerizing (a) 0.97 to 1.03 molar equivalent of a diamine component containing 0.40 molar equivalent or more of aromatic diamine compound represented by the general formula (DA1), and (b) an acid anhydride component containing (1-n.sub.1 /2) molar equivalent of a tetracarboxylic dianhydride and n.sub.1 molar equivalent of at least one selected from the group consisting of maleic anhydride and maleic derivative anhydride, wherein n.sub.1 ranges from 0.02 to 0.40.

Abstract: This invention relates to melt processable copolymer of etherimideimide/etherimide herein-after identified as PEII/PEI copolymer of following structural formula(I). ##STR1## wherein, R and R' are independently selected from the groups of ##STR2## Ar and Ar' are independently selected from the groups of ##STR3## (wherein, R1 is H or C1-C6 alkyl group,R2 is II or C1-C4 alkyl group, andR3 is --O--, --CO--, --SO--, --SO2--.); andn and m are independently an integer between 5 and 500.

Abstract: Controlled molecular weight phenylethynyl terminated imide oligomers (PETIs) have been prepared by the cyclodehydration of precursor phenylethynyl terminated amic acid oligomers. Amino terminated amic acid oligomers are prepared from the reaction of dianhydride(s) with an excess of diamine(s) and subsequently endcapped with phenylethynyl phthalic anhydride(s) (PEPA). The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N,N-dimethylacetamide under nitrogen at room temperature. The amic acid oligomers are subsequently cyclodehydrated either thermally or chemically to the corresponding imide oligomers. Direct preparation of PETIs from the reaction of dianhydride(s) with an excess of diamine(s) and endcapped with phenylethynyl phthalic anhydride(s) has been performed in m-cresol. Phenylethynyl phthalic anhydrides are synthesized by the palladium catalyzed reaction of phenylacetylene with bromo substituted phthalic anhydrides in triethylamine.

Abstract: A process is disclosed for making circuit elements by photolithography comprising depositing an antireflective polyimide or polyimide precursor layer on a substrate and heating the substrate at 200.degree. C. to 500.degree. to provide a functional integrated circuit element that includes an antireflective polyimide layer. The antireflective polyimide layer contains a sufficient concentration of at least one chromophore to give rise to an absorbance sufficient to attenuate actinic radiation at 405 or 436 nm. Preferred chromophores include those arising from perylenes, naphthalenes and anthraquinones. The chromophore may reside in a dye which is a component of the polyimide coating mixture or it may reside in a residue which is incorporated into the polyimide itself.

Abstract: Polyamideimide resins having the formula (I) ##STR1## in which repeating units are bound in a head to tail or head to head manner,R is at least two divalent groups selected from the group consisting of ##STR2## (cis-, trans- conformational mixture) wherein one divalent group is ##STR3## group in a PAI molecule, produced by introducing isophorone diamine into the conventional aromatic polyamideimide resins.

Abstract: This invention concerns positive-working photodefinable polyimide precursors which make use of chemical amplification based on photoacid catalyzed cleavage of acid labile-poly(amic acetal esters).

Abstract: A polyimide comprises structural units represented by the following formula: ##STR1## wherein Ar is a group consisting of 10-90 mole % of a first specific structural sub-unit and 90-10 mole % of a second particular structural sub-unit. A process for the production of the polyimide and a thermosetting resin composition comprising the polyimide and a particular polymaleimide are also disclosed.

Abstract: This invention relates to a novel polyimide or polyimide copolymer having excellent heat resistance and greatly improved processability, and has a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the polyimide or polyimide copolymer and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition.The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein L is an oxygen atom, carbonyl, isopropylidene or hexafluoroisopropylidene, and X is ##STR2## and Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member.

Abstract: A copolyimide was prepared by reacting 3,4'-oxydianiline (3,4'-ODA) with a dianhydride blend comprising, based on the total amount of the dianhydride blend, about 67 to 80 mole percent of 4,4'-oxydiphthalic anhydride (ODPA) and about 20 to 33 mole percent of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA). The copolyimide may be endcapped with up to about 10 mole percent of a monofunctional aromatic anhydride and has unbalanced stoichiometry such that a molar deficit in the dianhydride blend is compensated with twice the molar amount of the monofunctional aromatic anhydride. The copolyimide was used to prepare composites, films and adhesives. The film and adhesive properties were significantly better than those of LaRC.TM.-IA.

Abstract: Disclosed is a thermally-stable SnO.sub.2 -surfaced polyimide film wherein the electrical conductivity of the SnO.sub.2 surface is within the range of about 3.0.times.10.sup.-3 to about 1.times.10.sup.-2 ohms.sup.-1,. Also disclosed is a method of preparing this film from a solution containing a polyamic acid and SnCl.sub.4 (DMSO).sub.2.

Abstract: Disclosed are bis-meta-benzotrifluoride compounds having the general formula ##STR1## where each A is independently selected from the group consisting of NO.sub.2, NH.sub.2, and NH.sub.3.sup.+ Z.sup.-, Z.sup.- is an anion and B is selected from the group consisting of O, CO, S, SO, and SO.sub.2. The diamine compounds are useful as monomers in making polyimides, polyamide-imides, and polyamides.

Abstract: Polyimides comprising recurring units of the following general formula (1) ##STR1## wherein Ar.sub.1 represents a tetravalent aromatic group and each Ar.sub.2 represents a divalent aromatic group. Polyimide copolymers and preparations of the polyimides and the polyimide copolymers are also described.

Abstract: Solutions of polyimide-forming substances containA) polyamines andB) amides and/or esters of tetracarboxylic acids, the amido or ester groups carrying substituents selected from the group consisting of carboxyl, sulfo and silicon-containing groups,and are used as polyimide coatings.

Abstract: A polyimide represented by the general formula (1): ##STR1## wherein Y represents a hydrocarbon group having 4 to 20 carbon atoms or a sulfur atom; each of R.sub.1 to R.sub.4, R.sub.i and R.sub.j represents a halogen atom, a hydrocarbon group having 1 to 6 carbon atoms or a halogen-containing hydrocarbon group having 1 to 6 carbon atoms; each of a, b, c, d, e and f represents an integer of 0 to 4 satisfying a+b.ltoreq.4, c+d.ltoreq.4 and e+f.ltoreq.4; and X represents a tetravalent organic group having 2 or more carbon atoms.

Abstract: Polyimide polymers of the following recurring structure and the corresponding polyamic acids are disclosed: ##STR1## wherein AR.sub.1 is ##STR2## where X is O, S, SO, SO.sub.2, CO, C(CF.sub.3).sub.2, C(CH.sub.3).sub.2, Si(CH.sub.3).sub.2, or a single bond, wherein AR.sub.2 may be pyromellitic dianhydride, a substituted pyromellitic dianhydride, naphthanoic dianhydride, or ##STR3## where Y is O, S, SO, SO.sub.2, CO, C(CF.sub.3).sub.2, C(CH.sub.3).sub.2, Si(CH.sub.3).sub.2 --O--AR--O--, or a single bond, where AR is an aromatic nucleus.

Abstract: A negative birefringent film, useful in liquid crystal displays, and a method for controlling the negative birefringence of a polyimide film is disclosed which allows the matching of an application to a targeted amount of birefringence by controlling the degree of in-plane orientation of the polyimide by the selection of functional groups within both the diamine and dianhydride segments of the polyimide which affect the polyimide backbone chain rigidity, linearity, and symmetry. The higher the rigidity, linearity and symmetry of the polyimide backbone, the larger the value of the negative birefringence of the polyimide film.

Abstract: This invention relates to a novel thermoplastic and amorphous polyimide which is readily soluble in organic solvent, a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the thermoplastic polyimide and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition, a polyimide-based composite obtained by molding the above soluble and thermoplastic polyimide in combination with a fibrous reinforcement, and a fibrous reinforcement having a surface modified with the above polyimide.

Abstract: A solvent resistant copolyimide was prepared by reacting 4,4'-oxydiphthalic anhydride with a diaimine blend comprising, based on the total amount of the diamine blend, about 75 to 90 mole percent of 3,4'-oxydianiline and about 10 to 25 mole percent p-phenylene diamine. The solvent resistant copolyimide had a higher glass transition temperature when cured at 350.degree. , 371.degree. and 400.degree. C. than LaRC.TM.-IA. The composite prepared from the copolyimide had similar mechanical properties to LaRC.TM.-IA. Films prepared from the copolyimide were resistant to immediate breakage when exposed to solvents such as dimethylacetamide and chloroform. The adhesive properties of the copolyimide were maintained even after testing at 23.degree., 150.degree., 177.degree. and 204.degree. C.

Abstract: Polyimides comprising recurring units of the following general formula (1) ##STR1## wherein R.sub.1 represents a tetravalent aromatic group. Polyimide copolymers and preparations of the polyimides and the polyimide copolymers are also described.

Abstract: Solutions of polyimide-forming substances containA) aromatic or partly aromatic polyamines andB) amides or a mixture of esters and amides of tetracarboxylic acids.Solutions are useful as coating compositions.

Abstract: Copolyimides from 1,4-bis(4-aminophenoxy)-2-phenylbenzene and m- or p-phenylene diamine with biphenyl dianhydride exhibit a high Tg and reduced melt viscosity.