Curable polyimides and compositions thereof with very good dielectric properties are provided. Prepregs of these compositions laminated with copper foil to prepare copper clad laminates having Tg>150 C and Df<0.0025 are also provided.

In a first aspect, a polyimide film includes a polyimide derived from a dianhydride and a diamine. The dianhydride includes pyromellitic dianhydride, the diamine includes a benzimidazole, the molar ratio of dianhydride to diamine that forms the polyimide is in a range of from 0.85:1 to 0.99:1, and the polyimide film has a T.sub.g of 400° C. or higher, a tensile modulus of 6.0 GPa or more, and a coefficient of thermal expansion of 15 ppm/° C. or less over a temperature range of 50 to 500° C. In a second aspect, an electronic device includes the polyimide film of the first aspect.

An object is to provide a polyamic acid resin composition that can form a varnish with a low viscosity and serves to produce, through curing, coat film with good mechanical characteristics. Another object is to provide a polyamic acid resin composition in which the acid anhydride terminal group is low in reactivity with diamine and which can give a varnish that does not suffer significant precipitation of diamine. These objects can be met by a polyamic acid resin composition that contains: (a) polyamic acid and (b) a compound as represented by chemical formula (1). (In Chemical formula (1), Z is a di- or higher-valent organic group containing 2 or more carbon atoms, V is a structure as represented by chemical formula (2), and k is an integer of 2 or more.) (In In Chemical formula (2), δ represents oxygen or sulfur atom and W represents an electron-withdrawing group, and R.sup.11 and R.sup.12 represent independently a hydrogen atom or a hydrocarbon group containing 1 to 10 carbon atoms.

Provided is a polyimide excellent in heat resistance and colorless transparency and also excellent in flexibility and ultraviolet ray transmittance. The polyimide includes a structural unit represented by Formula (1a) and a structural unit represented by Formula (1b) wherein R is a specific aromatic group. ##STR00001##

A multilayered polyimide film includes a first polyimide layer containing fluorine-containing polymer particles and having a first surface and a second surface, and a second polyimide layer and a third polyimide layer respectively disposed on the first surface and the second surface. The second and the third polyimide layers contain organic silicon oxygen compound particles. The multilayered polyimide film has a coefficient of thermal expansion (CTE) between about 13 and about 30 ppm/° C.

A thermoplastic composition including a polycarbonatesiloxane-arylate; a phthalone compound; and optionally an additional component different from the polycarbonatesiloxane-arylate and the phthalone compound; wherein the phthalone compound has a formula: wherein Z.sub.1 represents the atoms necessary to complete a 9- to 13-membered single or fused aromatic ring structure, Z.sub.2 represents the atoms necessary to complete a pyridine or quinoline ring, each R.sub.1 and each R.sub.2 are independently halogen, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an aromatic or aliphatic thioether group, an aromatic or aliphatic carboxylic acid ester group, or an aromatic or aliphatic amide group, a is an integer from 0 to 6, b is an integer from 0 to 4, n is 1 or 2, and X is present only if n=2 and is a single bond or a divalent organic radical bonded to the Z.sub.1 ring structure through an ether, ketone, or thio linkage.

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The present invention provides a multilayer body of an inorganic substrate and a highly heat-resistant transparent film which has sufficient heat resistance and is able to be mechanically separated from the inorganic substrate after being subjected to various processes on the inorganic substrate since the adhesion between the highly heat-resistant transparent film and the inorganic substance is adequately weak. A multilayer body of a highly heat-resistant transparent film and an inorganic substrate, wherein: an adhesive is not substantially used; the peel strength between the highly heat-resistant transparent film and the inorganic substrate is 0.3 N/cm or less; and the CTE of the highly heat-resistant transparent film is 50 ppm/K or less.

A gas separation asymmetric membrane includes a porous layer having gas permeability; and a compact layer having gas separation capability which is formed on the porous layer in which the gas separation asymmetric membrane is formed using a polyimide compound which has a structural unit represented by Formula (I) and at least one structural unit selected from a structural unit represented by Formula (II) or a structural unit represented by Formula (III) and in which the viscosity, at 25° C., of a solution obtained by dissolving the polyimide compound in N-methylpyrrolidone at a concentration of 5% by mass is in a range of 2.2 to 22.0 mPa.Math.sec,

##STR00001##

in the formula, X.sup.1 represents a group having a structure represented by Formula (I-a) or (I-b).

##STR00002##

Provided are a photosensitive resin composition which has excellent pattern processabilities (high sensitivity and high resolution) and is excellent in chemical resistance and thermal resistance after thermally treated; a heat-resistant resin or heat-resistant resin precursor used for the composition; and a diamine compound which is a raw material of the resin and the precursor. The diamine compound is a diamine compound represented by a general formula (1).

##STR00001##

A poly(etherimide) includes repeating units derived from polymerization of a biphenol dianhydride and an organic diamine. A method of making the poly(etherimide) includes contacting the biphenol dianhydride and the organic diamine under conditions effective to provide a poly(etherimide). The poly(etherimide) can be useful in a variety of articles, for example in an optoelectronic component.