The present invention relates to a liquid crystal alignment agent composition including a copolymer for liquid crystal alignment agent containing two types of repeating units classified according to the types of diamine-derived functional groups, and a crosslinker compound in which the protecting group having a specific structure was introduced, a method for preparing a liquid crystal alignment film using the same, and a liquid crystal alignment film and a liquid crystal display device using the same.

A method of manufacturing a bump structure includes forming a passivation layer over a substrate. A metal pad structure is formed over the substrate, wherein the passivation layer surrounds the metal pad structure. A polyimide layer including a polyimide is formed over the passivation layer and the metal pad structure. A metal bump is formed over the metal pad structure and the polyimide layer. The polyimide is a reaction product of a dianhydride and a diamine, wherein at least one of the dianhydride and the diamine comprises one selected from the group consisting of a cycloalkane, a fused ring, a bicycloalkane, a tricycloalkane, a bicycloalkene, a tricycloalkene, a spiroalkane, and a heterocyclic ring.

A photosensitive polyimide resin composition containing: a ring-closed polyimide resin (A) having a structure represented by Formula (1); and a polyfunctional radically polymerizable compound (B) having radically polymerizable functional groups and oxyalkylene groups, wherein a number of the radically polymerizable functional groups in the polyfunctional radically polymerizable compound (B) is 3 or greater and 100 or less, and wherein a total number of moles of the oxyalkylene groups added in the polyfunctional radically polymerizable compound (B) is 5 or greater and 100 or less.

A polyimide precursor composition that exhibits excellent tensile strength and breaking elongation, and that provides a film containing an alicyclic polyimide resin; a method for producing a polyimide film using the polyimide precursor composition; and a permanent film that contains an alicyclic polyimide resin and that exhibits excellent tensile strength and breaking elongation. The polyimide precursor composition is a mixture of a resin precursor component which is a polyamic acid including an alicyclic backbone having a predetermined structure, a monomer component that includes an aromatic diamine compound having a predetermined structure or an alicyclic tetracarboxylic acid di-anhydride having a predetermined structure; an imidazole compound having a predetermined structure; and a solvent.

A polyimide resin including a structural unit A derived from a tetracarboxylic dianhydride and a structural unit B derived from a diamine compound, wherein the structural unit A includes a structural unit (A-1) derived from a compound represented by the following formula (a-1), and the structural unit B includes a structural unit (B-1) derived from a compound represented by the following formula (b-1): ##STR00001## wherein m and n in the formula (b-1) each independently are an integer of 0 or 1.

Provided is a polyimide resin composition and a production method thereof, wherein the polyimide resin composition contains an alicyclic polyimide resin having a structural unit represented by the following general formula (1) and inorganic particles of at least one selected from the group consisting of titanium dioxide, barium titanate, and zirconium oxide, wherein the alicyclic polyimide resin has a glass transition temperature of 260 C. or higher, ##STR00001## wherein R.sub.1 represents a tetravalent alicyclic hydrocarbon group having a carbon number of from 4 to 22, and R.sub.2 represents a divalent aliphatic hydrocarbon group having a carbon number of from 2 to 28 and/or a divalent aromatic hydrocarbon group having a carbon number of from 6 to 27.

The present invention provides an alkali-soluble resin with which a cured film having high extensibility, reduced stress, high adhesion to a metal, and high heat resistance can be obtained, and a photosensitive resin composition containing the alkali-soluble resin, and the present invention is an alkali-soluble resin (A) including a structure represented by a general formula (1) wherein X.sup.1 represents a divalent organic group having 2 to 100 carbon atoms, Y.sup.1 and Y.sup.2 each represent a divalent to hexavalent organic group having 2 to 100 carbon atoms, X.sup.2 represents a tetravalent organic group having 2 to 100 carbon atoms, p and q each represent an integer in a range of 0 to 4, and n.sup.1 and n.sup.2 each represent an integer in a range of 5 to 100,000, wherein (I) and (II) described below are satisfied: (I) an organic group having an aliphatic chain having 8 to 30 carbon atoms is contained as X.sup.1 of the general formula (1) at a content of 30 to 70 mol % based on 100 mol % of a total of X.sup.1 and X.sup.2, and (II) an organic group having a diphenyl ether structure is contained as Y.sup.1 of the general formula (1) at a content of 1 to 30 mol % based on 100 mol % of a total of Y.sup.1 and Y.sup.2.

The present invention relates to a crosslinking agent compound in which a terminal crosslinkable functional group is capped with a silane-based protecting group, a photosensitive composition including the same, and a photosensitive material using the same.

In a first aspect, a polyimide film includes 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 a b* of 1.25 or less and a yellowness index of 2.25 or less for a film thickness of 50 m. The polyimide film is formed by: (a) polymerizing the dianhydride and the diamine in the presence of a first solvent to obtain a polyamic acid solution; (b) imidizing the polyamic acid solution to form a substantially imidized solution; (c) casting the substantially imidized solution to form a film; and (d) drying the film.

In a first aspect, a polyimide film includes 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 a tensile modulus of 5.5 GPa or more, a b* of 1.4 or less and a yellowness index of 2.25 or less for a film thickness of 50 m. In a second aspect, an electronic device includes the polyimide film of the first aspect.