Abstract: Provided is a method for quantitative evaluation of mar- and scratch-induced surface damage on polymeric and coating materials. The method for quantitative evaluation of scratch-induced damage on polymeric and coating materials includes: preparing a test specimen of polymeric and coating materials; inducing a scratch damage on the surface of the test specimen; representing the scratch damage formed on the test specimen as corresponding color coordinates; and calculating a quantitated scratch damage index from a combination of a load applied to the surface of the test specimen and the color coordinates corresponding to the scratch damage.

Abstract: Provided is a method for quantitative evaluation of mar- and scratch-induced surface damage on polymeric and coating materials. The method for quantitative evaluation of scratch-induced damage on polymeric and coating materials includes: preparing a test specimen of polymeric and coating materials; inducing a scratch damage on the surface of the test specimen; representing the scratch damage formed on the test specimen as corresponding color coordinates; and calculating a quantitated scratch damage index from a combination of a load applied to the surface of the test specimen and the color coordinates corresponding to the scratch damage.

Abstract: The present invention relates to a reactive photo acid-generating agent and a heat-resistant photoresist composition comprising the same. In particularly, the present invention relates to the heat-resistant photoresist composition comprising the photo acid-generating agent expressed by the following formula (1), which can increase the degree of polymerization, and polyamide oligomers having acetal or its cyclized derivatives, which have an ability of that light-exposed area is dissolved in the developer and light-unexposed area is convertible to a heat-resistant polymer in the latter heating process and thus, it can be used for passivation layer, buffer coat or layer-insulating film of the multilayer printed circuit board, wherein and R are the same as defined in the detailed description of the Invention.

Abstract: The present invention relates to a reactive photo acid-generating agent and a heat-resistant photoresist composition comprising the same.

Abstract: The present invention relates to a process of preparing polycarbonate, more specifically to a process of preparing polycarbonates by solid state polymerization using microwave radiation, which comprises steps of preparing polycarbonate prepolymer having a certain range of viscosity average molecular weight; converting said polycarbonate prepolymer into crystalline particles having a certain degree of crystallinity; and producing polycarbonates by solid state polymerization of said crystalline particles by applying microwave radiation, thus resulting in production of high quality polycarbonates with high molecular weight within short time.

Abstract: The present invention relates to polyamide-imides having head-to-tail backbone and more particularly, to polyamide-imimdes having head-to-tail ragularity to provide excellent heat and chemical resistance, physical and mechanical properties, processability, and gas permeability and selectivity.

Abstract: The present invention relates to a process of preparing polycarbonates and more particularly, to the process of preparing polycarbonates through a melt polymerization reaction of dihydroxyaryl compounds with diarylcarbonate, wherein said melt polymerization is performed in the presence of a mixed catalyst composed of an oxygen (O) or sulfur (S) containing compound having lone-pair electrons and an alkali metal or alkaline earth metal salt in an appropriate ratio at a reduced temperature by accelerating a reaction rate to obtain high quality polycarbonates with higher than 15,000 g/mole of a viscosity average molecular weight and improved color.

Abstract: The present invention relates to a process of preparing polycarbonates and more particularly, to the process of preparing polycarbonates through a melt polymerization reaction of dihydroxyaryl compounds with diarylcarbonate, wherein said melt polymerization is performed in the presence of a mixed catalyst composed of an oxygen (O) or sulfur (S) containing compound having lone-pair electrons and an alkali metal or alkaline earth metal salt in an appropriate ratio at a reduced temperature by accelerating a reaction rate to obtain high quality polycarbonates with higher than 15,000 g/mole of a viscosity average molecular weight and improved color.

Abstract: The present invention relates to a process of preparing polycarbonates, more specifically to a process of preparing polycarbonates by solid state polymerization using microwave radiation, which comprises steps of preparing polycarbonate prepolymer having a certain range of viscosity average molecular weight; converting said polycarbonate prepolymer into crystalline particles having a certain degree of crystallinity; and producing polycarbonates by solid state polymerization of said crystalline particles by applying microwave radiation, thus resulting in production of high quality polycarbonates with high molecular weight within short time.

Abstract: The present invention relates to a process for the preparation of polycarbonates, more specifically to a process for the preparation of polycarbonates by a solid polymerization of prepolymers obtained by the polymerization between aromatic dihydroxides and diarylcarbonates, which comprises: a) preparing said prepolymer having a viscosity average molecular weight of 4,000-18,000 g/mole; b) preparing a microporous foam by injecting high-pressure inert gas; and c) preparing polycarbonates by a solid polymerization, which facilitates the removal of phenol, a by-product, and enhances molecular weight of polycarbonates without using any catalyst due to the relatively high polymerization rate.

Abstract: The invention herein relates to a process of preparing a novel polyimide foam having superior heat-resistance, flame retardancy, homogeneous size and distribution of cells, and low density, wherein a polyimide precursor in a granular form is prepared by means of using heterocyclic amine as catalyst and then foaming. According to the present invention, the preparing process of a polyimide foam comprises reacting aromatic carboxylic acid or the anhydrides thereof with an excess of aliphatic univalent alcohol to yield an aromatic ester solution. To the aromatic ester solution, divalent amines or the mixture thereof were added in the equivalent amount of said carboxylic acid or the anhydrides thereof in addition to a catalyst and surfactant to yield a polyimide. Then, the precursor in a granular form mixture was imidized while foaming by means of pre-heating and then heating in a microwave oven, after which was cured at a high temperature.

Abstract: The invention herein relates to a soluble polyimide resin having a dialkyl substituent for a liquid alignment layer, wherein aliphatic tetracarboxylic dianhydride and aromatic diamine having a dialkyl substituent are used to yield said soluble polyimide resin which has superior heat-resistance, solubility, transparency, and liquid crystal alignment capacity. According to the present invention, the soluble polyimide polymer having a dialkyl substituent, for a liquid crystal alignment layer, comprising the following a repetitive unit of formula 1: ##STR1## Consequently, the polyimide resin under the present invention not only has superior heat-resistance but also excellent solubility and transparency, which could be applicable as a liquid crystal alignment layer for the TFT-LCD requiring a low temperature processing.

Abstract: The invention herein relates to a novel soluble polyimide resin comprising polyalicyclic structures and the process of preparation of the same, wherein aromatic tetracarboxylic dianhydride and novel aromatic diamine having an polyalicyclic group with various structures are used to yield a novel form of a polyimide resin, which has superior heat-resistance, solubility, and transparency.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance and solubility, which is prepared by means of reacting diamine monomers having a novel chemical structure with various types of aromatic carboxilic dianhydrides, in stead of aromatic diamine used for the preparation of the conventional polyimide resin. As a result, the polymers so obtained had the glass transition temperature of 260.degree. C..about.410.degree. C. and showed a increase in solubility in proportion to the increase in a number of the aromatic rings between two phenyl groups.

Abstract: The invention herein relates to a soluble polyimide resin for a liquid crystal alignment layer and the manufacturing method thereof, wherein a mixture of aliphatic tetracarboxylic acid dianhydrides and aromatic diamine having aliphatic side chains are used to yield a soluble polyimide resin which has superior heat-resistance, solubility, surface hardness, transparency and liquid crystal alignment capacity.The soluble polyimide resin having alkoxy substituents, for a liquid crystal layer, according to the present invention, is manufactured by adding a mixture of dioxotetrahydrofuran 3-methylcyclohexene-1,2-dicarboxylic dianhydride, which is an aliphatic tetracarboxylic acid dianhydride and aromatic tetracarboxylic acid dianhydride to a mixture of aromatic diamine, and said dioxotetrahydrofuran 3-methylcyclohexene- 1,2-dicarboxylic dianhydride is used in the amount of 50 to 99 mol % to the total amount of anhydrides.

Abstract: The invention herein relates to a soluble polyimide resin and the process of preparation of the same, wherein aromatic tetracarboxylic dianhydride and aromatic diamine having an alicyclic group with various structures of substituted alkyl groups are used to yield a novel form of a polyimide resin, which has superior heat-resistance, solubility and transparency.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance and solubility, which is prepared by means of reacting aromatic diamine monomers having a novel chemical structure with various types of aromatic tetracarboxilic acid dianhydrides, in stead of aromatic diamine used for the preparation of the conventional polyimide resin. As a result, the polymers so obtained had the glass transition temperature of 250.degree. C..about.400.degree. C. and showed a increase in solubility in proportion to the increase in volume of the alkyl group.

Abstract: A polyarylether of the formula (VIII) ##STR1## wherein wherein Z' is 1-3 optionally substituted rings selected from the group consisting of an aromatic ring, a hetero aromatic ring or an aliphatic ring.A is --R.sub.1 --Z--Y in which R.sub.1 is H, C.sub.1 -C.sub.30 -alkyl or -aralkyl or phenyl, Z is a direct bond or CH.sub.2, S, O or NH, Y is CH.sub.3, OR.sub.3, SR.sub.3, NHR.sub.3, N(R.sub.3).sub.2, COOR.sub.3, COOM, SO.sub.3 R.sub.3 or SO.sub.3 M in which R.sub.3 is C.sub.1 -C.sub.30 alkyl and M is alkali metal,produced from 3,6-dihalogen- or -dintro-1,2,4,5-diimide having an N,N-substituent and which is suitable for use as a monomer for high temperature structural and functional polymers, and a process for producing the same are disclosed.

Abstract: The invention herein relates to a soluble polyimide resin for a liquid crystal alignment layer and the process of preparation of the same, wherein aliphatic tetracarboxylic dianhydride and aromatic diamine having the amide group are used to yield a novel form of a polyimide resin having superior heat-resistance, solubility, transparency, and liquid crystal alignment capacity.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance, solubility, liquid crystal alignment property, and high pretilt angle, which is prepared by means of jointly using the aromatic diamine, used for the preparation of the conventional polyimide resin, and the aromatic diamine having a long alkyl chain with a substituted amide group, and reacting the same with various types of carboxylic dianhydride.

Abstract: The disclosure describes a process for preparing a polyamideimide resin having high molecular weight in a simple manner wherein major problems of the prior processes such as low heat resistance and low melt flowability are improved. The process comprises condensation of an aromatic tricarboxylic acid anhydride and an aromatic diamine in a polar solvent, subjecting the resulting diimidedicarboxylic acid to acyl halogenating agent treatment to give an intermediate having good reactivity at low temperature, and then subjecting the latter to direct polymerization by using diamine as a nucleophilic agent to give a polyamideimide resin having high molecular weight. The polyamideimide resin prepared by the present invention can be used as major heat resistant structural material in advanced industries and as paint, sheet, adhesives, sliding material, fiber and film having heat resistance.

Abstract: The disclosure describes a cyclohexane-1,2,4,5-diimide derivative which can be used for the production of colorless transparent polymer and novel engineering plastics having good processability and solubility with an excellent physical property, and a process for preparing the same which comprises reacting a bicyclooctene-1,2,4,5-tetracarboxylic anhydride with alkylamine and aniline derivative and then oxidizing the resulting product with ozone, potassium permanganate, ruthenium chloride hydroxide and aqeous hydrogen peroxide under non-basic condition to convert double bond to dicarboxylic acid or dialdehyde without destroying the imide group.

Abstract: A polyamideamic acid resin prepolymer represented by formula A having isophorone diamine as one of monomers, ##STR1## in which k, l, m and n are integer of 1 or more, respectively, and ##EQU1## --R-- is at least one group selected from the group consisting of ##STR2## --R'-- is a cis- and trans-conformational mixture of ##STR3## high heat resistant polyamideimide foam produced therefrom, and processes for producing them are disclosed.