348 results about "Tetrolic acid" patented technology

The invention discloses a polyimide liquid crystal vertical alignment agent, a prepration method and a liquid crystal box prepared thereby. The liquid crystal vertical alignment agent is prepared by dissolving soluble polyimide which accounts for 2.5-5% of the weight of the alignment agent into an organic solvent, the soluble polyimide is prepared by leading 1-50 parts by weight of tetracarboxylic dianhydride, 1-50 parts by weight of diamine with a special structure, 1-50 parts by weight of diamine and 40-80 parts by weight of organic solvent to react under the protection of nitrogen and at the temperature of 160-180 DEG C for 5-12 hours, and the diamine with the special structure is prepared by leading HO-B-OH, a catalyst, the organic solvent, halogenated hydrocarbon X-R and dinitro-substituted benzoyl chloride to carry out three-step reaction. The polyimide of a liquid crystal vertical alignment film formed by using the liquid crystal vertical alignment agent disclosed by the invention is soluble, a pretitle angle of the liquid crystal box prepared by spin-coating the polyimide liquid crystal vertical alignment agent is close to 90 degrees, and a liquid crystal display prepared thereby has excellent performances of fast response, wide viewing angle, high contrast degree and the like.

There is provided an anti-reflective coating forming composition for use in a lithography and for forming an anti-reflective coating that can be developed with an alkaline developer for photoresist, and a method for forming photoresist pattern by use of the anti-reflective coating forming composition. Concretely, the composition comprises a polyamic acid produced from a tetracarboxylic dianhydride compound and a diamine compound having at least one carboxyl group, a compound having at least two epoxy groups, and a solvent.

Disclosed is a novel tetracarboxylic acid compound having excellent characteristics such as high transparency, low dielectric property, low water absorption, low thermal expansion, solvent solubility and etching characteristics, while exhibiting high heat resistance at the same time. This tetracarboxylic acid compound is useful as a raw material monomer for producing a polyesterimide or a polyamideimide. Specifically disclosed is a tetracarboxylic acid compound represented by the general formula (1) or (2) below.

In the formulae, A represents a divalent group; X¹, X² and X³ respectively represent a hydrogen atom or the like; R¹, R², R³ and R⁴ respectively represent a carboxyl group or an acid anhydride group; n represents 1 or 2; and ring B represents a cyclic group.

The invention provides liquid crystal alignment agents for photo-alignment, liquid crystal photo-alignment layers, and liquid crystal displays using the same. The liquid crystal alignment agents contain tetracarboxylic dianhydride mixture including cyclopentane tetracarboxylic dianhydride, which is reacted with specific diamine to obtain polyamide acid or its derivatives. The liquid crystal alignment agents are applied to form a photo-alignment film with excellent alignment property and high light transmittance, because of light sensitivity of the chemical change caused by illumination. In addition, the photo-alignment film is applied in liquid crystal displays, the electrical characteristics required by liquid crystal alignment film is satisfied, the voltage maintaince ratio is high, the iron amount is little, the remained charge amount is little, etc.

A photosensitive polyimide resin precursor composition capable of providing a polyimide resin that is not substantially colored, is transparent and has heat resistance, an optical polyimide resin obtained from the composition, and an optical waveguide using the polyimide resin. The photosensitive polyimide resin precursor composition contains (a) 100 parts by weight of a polyamic acid obtained from a tetracarboxylic acid dianhydride and a diamine, (b) 0.01 parts by weight or more and less than 5 parts by weight of a 1,4-dihydropyridine derivative, (c) 5-50 parts by weight of a glycol (ether). The optical polyimide resin is obtained by irradiating the photosensitive resin precursor composition with UV light, followed by exposure, heating, development, and then heating. The optical waveguide comprises a core layer comprising the optical polyimide resin, and a cladding layer thereof.

This invention relates to a laminate which changes in dimension to such a small extent as not to cause curling and warpage when the ambient humidity changes and is useful for flexible printed wiring boards. The laminate possesses a polyimide layer or layers of polyimides formed on a conductor by coating and at least one of the polyimide layers is composed of polyimide of low hygroscopic expansion obtained by the reaction of diamines containing 20 mol % or more of 4,4′-diamino-2,2′-dimethylbiphenyl with a tetracarboxylic acid compound and exhibiting a coefficient of linear hygroscopic expansion of 15×10⁻⁶/% RH or less.

Disclosed are a gas separation membrane and a gas separation method in which at least one species of organic vapor is separated and recovered from an organic vapor mixture using the gas separation membrane. The gas separation membrane is made of an aromatic polyimide composed of a tetracarboxylic acid component consisting of an aromatic ring-containing tetracarboxylic acid and a diamine component comprising 10 to 90 mol % of a combination of (B1) 3,4′-diaminodiphenyl ether and (B2) 4,4′-diaminodiphenyl ether at a B1 to B2 molar ratio, B1/B2, ranging from 10/1 to 1/10, and 10 to 90 mol % of other aromatic diamine.

An object of the present invention is to provide a polyimide precursor composition that can be cured at low temperatures (250° C. or lower), while having a low viscosity even at a high concentration, and a method of producing the same. Another object of the present invention is to provide a polyimide coating film obtained from the polyimide precursor composition and having good physical properties, and a method of producing the same. Furthermore, another object of the present invention is to provide a photosensitive resin composition containing the polyimide precursor composition, and a method of producing the same. These objects can be achieved by the polyimide precursor composition containing an imidized tetracarboxylic acid having a specific structure and a diamine having a specific structure.

The invention relates to a diamine, a polymer obtained from a reaction with the presence of the diamine, a liquid crystal aligning agent containing the polymer, a liquid crystal alignment layer and a liquid crystal display device, wherein the diamine contains alkaline nitrogen atoms in diphenylamine structure at two parts of a molecule, so that the diamine reacts with tetracarboxylic dianhydride to obtain a liquid crystal aligning agent containing polyamide acids or derivatives thereof. Moreover, the liquid crystal display device made of the liquid crystal alignment layer formed by the liquid crystal aligning agent exhibits low ion density and long-term reliability.

The invention provides tetracarboxylic dianhydride containing triazole, a polymer, a liquid crystal aligning agent, a liquid crystal aligning membrane, and a display element. The tetracarboxylic dianhydride is represented by the formula (1); wherein in the formula (1), the X represents a divalent organic group containing at least one triazole ring, the R1 and R2 individually represent one of trivalent groups, which are represented in the description; and at least one hydrogen atom of these groups can be replaced by a methyl group, an ethyl group, or a phenyl group. The liquid crystal aligning agent can form a liquid crystal aligning membrane that is hard to peel off or eliminate.