A polyimide luminescent material, a preparation method, and a used thereof are disclosed; the polyimide luminescent material includes a polyimide resin and a rare earth complex distributed in the polyimide resin, wherein the polyimide resin is a condensation polymer of an aromatic diamine containing a bidentate chelate ligand and an aromatic dianhydride, and the rare earth complex and the bidentate chelate ligand are connected by a chemical bond. The luminescent material has enhanced fluorescence intensity, thermal stability, and mechanical properties. The preparation method is simple and easy, and is suitable for industrial production.

The present application provides a flexible substrate and a method of manufacturing the same. The flexible substrate includes a base substrate, the flexible substrate is a polyimide film, wherein the polyimide film comprises polyimide having a structural formula of

##STR00001##

and the polyimide has a rigid segment and a flexible segment. The polyimide film is divided into rigid regions and a flexible region, wherein the rigid region is mainly constituted by the rigid segment, and the flexible region is mainly constituted by the flexible segment. Because the polyimide has the rigid segment and the flexible segment, it is used in flexible substrates.

The present application relates to a polyimide and a manufacturing method therefor, thereby providing a polyimide capable of implementing excellent adhesion force while maintaining the inherent characteristics of the polyimide, and a manufacturing method therefor.

Provided is a polyamide-imide film including: a polyamide-imide resin and a porphyrin-based dye. The polyamide-imide film has excellent optical properties, and, in particular, may maintain an excellent yellow index even in a repeated temperature change environment.

Provided are a polyamideimide resin, and a polyamideimide film and a window cover film including the same. More particularly, a polyamideimide resin for preparing a polyamideimide film which satisfies both optical properties and mechanical properties which are in a trade-off relationship with each other and has more improved mechanical properties than a conventional polyamideimide film, a polyamideimide film using the same, and a window cover film including the same are provided.

A polyimide resin includes structural unit A derived from tetracarboxylic dianhydride and structural unit B derived from diamine, wherein unit A includes at least one unit selected from the group consisting of unit (A-1) derived from a compound represented by Formula (a-1) and unit (A-2) derived from a compound represented by Formula (a-2), and unit B includes unit (B-1) derived from a compound represented by Formula (b-1) and includes unit (B-2) derived from a compound represented by Formula (b-2).

##STR00001##

wherein X represents a single bond or an oxygen atom, and Ar represents a substituted or unsubstituted arylene group.

##STR00002##

wherein Z.sup.1/Z.sup.2 represent a divalent aliphatic or aromatic group, R.sup.1/R.sup.2 represent a monovalent aromatic or aliphatic group, R.sup.3/R.sup.4 represent a monovalent aliphatic group, R.sup.5/R.sup.6 represent a monovalent aliphatic or aromatic group, m&n represent an integer of 1 or greater, and a sum of m+n represents an integer from 2-1000.

The present invention provides a polyimide-based copolymer and electronic component and field effect transistor comprising the same. The polyimide-based copolymer comprises a copolymer of dianhydride and heterocyclic diamine, wherein the heterocyclic diamine has two benzene rings, and there are two ether bonds, two thioether bonds, or one ether bond and one thioether bond between the two benzene rings. The novel polyimide-based copolymer of the invention has excellent thermal-mechanical stability, has potential application prospects, and can be used as a substrate for flexible electronics.

The present invention provides a resin composition having a high sensitivity and serving to produce a cured film with a low water absorption rate. The resin composition includes: (a) an alkali-soluble resin and (b1) an amido-phenol compound containing a phenolic hydroxyl group in which a monovalent group as represented by the undermentioned general formula (1) is located at the ortho position and/or (b2) an aromatic amido acid compound containing a carboxy group in which a monovalent group as represented by the undermentioned general formula (2) is located at the ortho position: ##STR00001##
wherein in general formula (1), X is a monovalent organic group having an alkyl group that contains 2 to 20 carbon atoms and bonds directly to the carbonyl carbon in general formula (1) or a monovalent organic group that has —(YO).sub.n—; and in general formula (2), U is a monovalent organic group that has an alkyl group containing 2 to 20 carbon atoms and bonding directly to the amide nitrogen in general formula (2) or a monovalent organic group that has —(YO).sub.n—; wherein Y is an alkylene group containing 1 to 10 carbon atoms and n is an integer of 1 to 20.

A resin composition includes a first prepolymer and a second prepolymer, the first prepolymer being prepared from a first mixture subjected to a prepolymerization reaction, the second prepolymer being prepared from a second mixture subjected to a prepolymerization reaction, wherein the first mixture includes a maleimide resin and a benzoxazine resin, and the second mixture includes a maleimide resin and a bis(trifluoromethyl)benzidine. The resin composition may be used to make various articles, such as a prepreg, a resin film, a laminate or a printed circuit board, and at least one of the following properties can be improved, including copper foil peeling strength, dissipation factor, ratio of thermal expansion, cure shrinkage and glass transition temperature.

The present invention provides a polyamide-imide copolymer, which is obtained by copolymerizing an aromatic diamine monomer, a dianhydride monomer and an aromatic dicarbonyl monomer, wherein the aromatic diamine monomer comprises a diamine containing an amide group (—CONH.sub.2) represented by formula (1), and Q.sup.1, X.sup.1, X.sup.2, R.sup.1, R.sup.2, Y.sup.1, Y.sup.2 and m are as defined herein:

##STR00001##