Daicel Chemical Industries, Ltd.

Asahi Kasei Kogyo Kabushiki Kaisha

Koichi Hatada

Yoshio Okamoto

Tohru Shibata

Ichiro Okamoto

Hajime Namikoshi

Tatsuki Kitayama

Hiroyuki Nakamura

Polysaccharide derivatives as separating agents

A separation agent essentially comprises an aliphatic or aromatic ester of a polysaccharide, except for cellulose acetate and an aromatic ester of cellulose. It is useful for separation of various chemical substances, especially optical resolution of optical isomers.

Optical resolution with .beta.-1,4-xylan dibenzoate

Optical resolution with .beta.-1,4-mannan tribenzoate

Optical resolution with tribenzoyl-b-1,4-chitosan

A new alkyl-substituted phenylcarbamate derivative of a polysaccharide, exclusive of cellulose, has an alkyl-substituted phenylcarbamoyl group for 80 to 100 percent of the hydroxyl groups attached to the polysaccharide and is useful to the optical resolution of racemic compounds.

Alkyl-substituted phenylcarbamate derivative of polysaccharide

An alkyl-phenylcarbamate derivative of a polysaccharide has in 80 to 100 percent of hydrogen atoms of the amino and hydroxyl groups an alkylphenyl-carbamoyl group having the formula (I): ##STR1## in which (1) at least one of R1 to R5 is a straight alkyl having 4 to 8 or a branched alkyl having 3 to 8 carbon atoms or at least two of R1 to R5 each are a straight alkyl having 1 to 3 when the polysaccharide is cellulose; (2) at least one of R1 to R5 is a straight alkyl having 1 to 8 carbon atoms or a branched alkyl having 3 to 8 carbon atoms when the polysaccharide is any one other than cellulose; and the other(s) of R1 to R5 is hydrogen. It is useful to optical separation of a racemic mixture.

Alkyl-phenylcarbamate derivative of polysaccharide

A mixture of chemical substances such as optical isomers, geometrical isomers and polymers having different molecular weight ranges is separated to each ingredient by use of a cellulose derivative having an aromatic ring in the chromatographic method.

Separating agent

A chromatographic resolving agent made of silica gel chemically bonded with an optically active polymer having either an asymmetric carbon atom in the main chain or molecular dissymmetry causing a helical structure of the main chain thereof.

Separation agent

Solvent-soluble copolymers having a number average molecular weight of about 1,000 to about 1,000,000 and comprising recurring units of the following formulae (I) and (II) (case A) or recurring unit of the following formulae (I), (II) and (III) (case B) or solvent-soluble graft copolymers having a number average molecular weight of about 1,500 to about 2,000,000 and comprising recurring units of the following formulae (I), (II) and/or (II'), and (IV) (case C) or recurring units of the following formulae (I), (II) and/or (II'), (III) and (IV) (case D), said recurring units being combined to form the main alkylene chain, wherein in the cases A and B the amount of the formula (I) unit is about 3 to 60 mol % of the total amount of the whole units, and in the cases C and D the amount of the formula (I) unit is about 5 to 60 mol % of the total amount of the units of formulae (I), (II) and/or (II'), and (IV), and in the cases B and D the amount of the formula (III) unit is about 1 to 40 mol % of the total amount of the whole units, and in the cases C and D the amount of the side chains enclosed in brackets of the formula (IV) unit is at least about 10% by weight of the amount of the main chain, exclusive of the bracketed grafted side chains, of the graft copolymer: ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 represents independently hydrogen, a straight or branched chain alkyl group having 1 to 4 carbon atoms or a halogen; R.sub.4 represents hydrogen or a straight or branched chain alkyl group having 1 to 10 carbon atoms; R.sub.5 represents an alkyl group having 1 to 6 carbon atoms, a phenyl group or a benzyl group; R.sub.6 represents hydrogen or a methyl group; R.sub.7 represents a straight or branched chain alkyl group having 1 to 10 carbon atoms, an aryl group, an aralkyl group or an aminoalkyl group; and n is an integer of 1 to 50. A resist having an excellent sensitivity to ionizing radiations and a high resolution, and also having a high dry etching resistance is provided by using these copolymers and graft copolymers.

Graft copolymers, process for the preparation thereof and ionizing

Solvent-soluble copolymers having a number average molecular weight of about 1,000 to about 1,000,000 and comprising recurring units of the following formulae (I) and (II) (case A) or recurring unit of the following formulae (I), (II) and (III) (case B) or solvent-soluble graft copolymers having a number average molecular weight of about 1,500 to about 2,000,000 and comprising recurring units of the following formulae (I), (II) and/or (II'), and (IV) (case C) or recurring units of the following formulae (I), (II) and/or (II'), (III) and (IV) (case D), said recurring units being ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 represents independently hydrogen, a straight or branched chain alkyl group having 1 to 4 carbon atoms or a halogen; R.sub.4 represents hydrogen or a straight or branched chain alkyl group having 1 to 10 carbon atoms; R.sub.5 represents an alkyl group having 1 to 6 carbon atoms, a phenyl group or a benzyl group; R.sub.6 represents hydrogen or a methyl group; R.sub.7 represents a straight or branched chain alkyl group having 1 to 10 carbon atoms, an aryl group, an aralkyl group or an aminoalkyl group; and n is an integer of 1 to 50. A resist having an excellent sensitivity to ionizing radiations and a high resolution, and also having a high dry etching resistance is provided by using these copolymers and graft copolymers.

Growing community of inventors

Ikeda, Japan

Koichi Hatada