A polyimide precursor solution includes a polyimide precursor that is a polymer of an aromatic tetracarboxylic dianhydride and an aromatic diamine compound, resin particles, an aqueous solvent containing water, and an amine compound having a boiling point of equal to or higher than 250° C. and equal to or lower than 300° C., in which a ratio of a volume of the resin particles to a volume of the amine compound (volume of resin particles/volume of amine compound) is equal to or more than 0.22 and equal to or less than 0.61.

Embodiments of the present disclosure provide for an aromatic dianhydride, a method of making an aromatic dianhydride, an aromatic dianhydride-based polyimide, a method of making an aromatic dianhydride-based polyimide, and the like.

In a first aspect, a polyimide film includes a polyimide derived from a dianhydride and a diamine. The dianhydride, the diamine or both the dianhydride and the diamine include an alicyclic monomer, an aliphatic monomer or both an alicyclic monomer and an aliphatic monomer. The polyimide film has an L* of at least 90, a b* of 1.25 or less, a yellowness index of 2.25 or less and a haze of less than 1% for a film thickness of 50 μm. In a second aspect, an electronic device includes the polyimide film of the first aspect.

Compositions of azobenzene-containing, photomechanically active, copoly(amic acids) and linear copolyimides including an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride are provided; and methods of making the same.

A polyimide precursor solution includes: a polyimide precursor; a resin particle having 55% by weight or more of a structural unit derived from a styrene derivative; and a mixed solvent containing a first organic solvent (S1) and a second organic solvent (S2), wherein the polyimide precursor solution satisfies the following conditions (1) to (4), condition (1): a weight ratio (S1/S2) of the first organic solvent (S1) to the second organic solvent (S2) is from 50/50 to 90/10, condition (2): a HSP distance between the first organic solvent (S1) and the resin particle is 11 or more and less than 16, condition (3): a HSP distance between the second organic solvent (S2) and the resin particle is 16 or more, and condition (4): a HSP distance between the mixed solvent and the polyimide precursor is 12 or less.

The present invention provides a resin film that is less likely to suffer peeling or creasing of a layer formed on the resin film in a high temperature process for producing a device and that can be used suitably to produce a product that requires transparency, where the resin film comprises a resin that has a repeating unit as represented by the chemical formula (1) and has a light transmittance of 68% or more at a wavelength of 400 nm, a glass transition temperature of 370° C. or more, and a weight loss starting temperature of 440° C. or more,

##STR00001##

where in the chemical formula (1), A denotes a tetravalent tetracarboxylic acid residue containing 2 or more carbon atoms and B denotes a divalent diamine residue containing 2 or more carbon atoms.

The present invention is a substrate for a display, the substrate having a film B including a polysiloxane resin on at least one surface of a film A including a polyimide resin, wherein the film B contains inorganic oxide particles therein, and the present invention has an object to provide a substrate for a display: being able to be applied to a color filter, an organic EL element, or the like without the need to carry out any complex operations; allowing high-definition displays to be manufactured; and being provided with a low CTE, a low birefringence, and flexibility.

An object of the present invention is to provide a polyimide copolymer excelling in solder heat resistance and an adhesive property, and a molded article thereof. A polyimide copolymer is obtained by copolymerizing: (A) an acid dianhydride ingredient; (B) a diamine and/or diisocyanate ingredient represented by the following general formulas (1) to (3):

##STR00001##

where in the formulas, X is an amino group or an isocyanate group, each of R.sup.1 to R.sup.8 is independently a hydrogen atom, an alkyl group having a carbon number of 1 to 4, an alkenyl group having a carbon number of 2 to 4 or an alkoxy group having a carbon number of 1 to 4, at least one of R.sup.1 to R.sup.4 is not a hydrogen atom, and at least one of R.sup.5 to R.sup.8 is not a hydrogen atom; and (C) a diamine and/or diisocyanate ingredient having at least one kind selected from an ether group and a carboxyl group.

The present invention provides a tetracarboxylic acid diester compound shown by the following general formula (1),

##STR00001##

wherein X.sub.1 represents a tetravalent organic group; and R.sub.1 represents a group shown by the following general formula (2),

##STR00002##

wherein the dotted line represents a bond; Y.sub.1 represents an organic group with a valency of k+1; “k” represents 1 or 2; and “n” represents 0 or 1. There can be provided a tetracarboxylic acid diester compound that can give a polyimide precursor polymer soluble in a safe organic solvent widely used as a solvent of a composition and usable as a base resin of a photosensitive resin composition.

Provided are a polyamic acid composition, a polyamideimide film thereof, and a method for preparing the polyamideimide film. More specifically, provided are a polyamideimide film capable of implementing excellent optical properties in addition to inherent physical properties of polyimide by using a polyamic acid composition including a combination of specific components, and a method for preparing the polyamideimide film.