The present invention provides a liquid crystal display device in which flicker and image sticking caused by long-term use are suppressed. The liquid crystal display device includes, in the following order: a first substrate; a liquid crystal layer; and a second substrate, the liquid crystal display device including an alignment film including a polymer containing a salicylic acid derivative functional group in a side chain on the liquid crystal layer side of at least one of the first substrate and the second substrate, the salicylic acid derivative functional group having a structure represented by the following formula (Z):

##STR00001##

An electrophotographic component includes a substrate and an optional cushioning layer disposed on the substrate. The optional cushioning layer comprises a material selected from the group consisting of silicones, fluorosilicones and fluoroelastomers. An optional release layer is disposed on the substrate and if present, on the optional cushioning layer. The optional release layer comprises a fluoropolymer. The substrate, the optional cushioning layer, the optional release layer, or any combination thereof, comprise a plurality of fluorinated boron nitride nanosheets. The electrophotographic component comprises at least one layer selected from the optional cushioning layer and the optional release layer.

The invention provides a selenium-containing polyimide polymer, preparation method and use thereof. The method comprises: (1) polymerizing a selenide diamine monomer with a dianhydride monomer to give a selenium-containing polyamic acid; and (2) performing thermal imidization on the selenium-containing polyamic acid obtained in the step (1) to give a selenium-containing polyimide polymer. In the invention, selenium is introduced into polyimides for increasing refractive index to 1.7-1.82, this greatly improves the defects of low refractive index of the existing polyimide materials, thereby expanding its applications in the optics field.

A resin composition for display substrates includes the following: the resin (a): a resin containing, as a main component, a repeating unit represented by the chemical formula (1), wherein the resin contains the total of 95 mass % or more of a tetracarboxylic acid residue A, having 2 or more carbon atoms and an SP value of 15 or more and 17 or less and a diamine residue having an SP value of 11 or more and 13 or less with respect to the total of 100 mass % of A and B contained in the resin; the solvent (b): a solvent having an SP value of 7.5 or more and less than 9.5; and the solvent (c): a solvent having an SP value of 9.5 or more and 14.0 or less; ##STR00001## wherein R.sup.1 and R.sup.2 independently represent a hydrogen atom, hydrocarbon group having 1 to 10 carbon atoms, alkylsilyl group having 1 to 10 carbon atoms, alkali metal ion, ammonium ion, imidazolium ion, or pyridinium ion.

The present invention discloses a novel diamine that has a structure bearing an intramolecular imide group and additionally an amide-substituted aromatic ring group at opposite sides of the imide group. The use of the novel diamine as a polymerization ingredient in polyimide production can provide a polyimide film which has remarkably improved mechanical and thermal properties while maintaining optical properties.

A polyamic acid according to an embodiment is formed by a polymerization reaction of a dianhydride compound, a first diamine compound represented by the following Formula 1, and a second diamine compound, which is different from the first diamine compound. A polyimide film derived from the polyamic acid may exhibit excellent heat resistance and improved optical properties:

##STR00001##

This invention relates to a polyimide-polybenzoxazole precursor solution, a polyimide-polybenzoxazole film, and a method of manufacturing the same, wherein a film manufactured using the polyimide-polybenzoxazole precursor solution of the invention is formed by copolymerizing a unit structure of diamine and dianhydride and a unit structure of diaminophenol and dicarbonyl chloride in an organic solvent, and is colorless and transparent, like conventional polyimide films, and can exhibit improved heat resistance and low birefringence.

A polyamide acid composition and a polyimide composition are obtained from a tetracarboxylic acid compound containing an aromatic tetracarboxylic acid compound having a naphthalene skeleton and a diamine compound containing an aromatic diamine compound having a biphenyl skeleton.

A polyimide has a repeating unit represented by general formula (1) and having a glass transition temperature (Tg) of 210 C. or higher:

##STR00001##

wherein A represents a divalent group represented by general formula (5) or a divalent organic group including a cyclic aliphatic group having 4 to 30 carbon atoms:

##STR00002##

wherein X represents a direct bond, an oxygen atom, a sulfur atom, a sulfonyl group (SO.sub.2), a carbonyl group (CO), an amide group (NHCO), an ester group (OCO), an alkylidene group having 1 to 15 carbon atoms, a fluorine-containing alkylidene group having 2 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, a phenylene group, or a fluorenylidene group, and each * represents a bonding position. The polyimide is intended to have high heat resistance, excellent optical properties, and dielectric properties while being made from a bio-derived resource.

A laminate includes a glass base, a silicone resin layer, and a polyimide resin layer. The polyimide resin layer includes a fluorine-atom-containing polyimide. When examined by infrared absorption, the polyimide resin layer gives a spectrum in which a ratio of an area of a peak appearing at 3,150 cm.sup.1 to 3,750 cm.sup.1 to an area of a peak appearing at 1,650 cm.sup.1 to 1,750 cm.sup.1 is 0.9 or less.