Nissan Chemical Industries Limited

Yasuhiro Takahashi

Yoshio Ohara

Kazutaka Arai

Fumio Suzuki

Koichi Maeda

Hisao Ikeda

Mitsunobu Matsumura

Yoshitane Watanabe

Katsuaki Miyaji

Hiroo Matsumoto

Hiroshi Murakami

Yasuo Takakuwa

Yoshitane Watanbe

Syuuzi Tsuchiya

Hirosi Murakami

Disclosed are a papermaking method comprising the steps of sheet-formation of an aqueous papermaking stock which contains a cellulose fiber or the said fiber and an inorganic filler, dewatering and drying, charaacterized by the addition of a starch ether derivative of a general formula (I): ##STR1## where St--O represents a starch molecule residue, R.sub.1, R.sub.2 and R.sub.3 independently represent an alkyl group having from 1 to 18 carbon atoms or a benzyl group, provided that two or more of these R.sub.1, R.sub.2 and R.sub.3 must not be a benzyl group or an alkyl group having from 5 to 18 carbon atoms at the same time, and any two of these R.sub.1, R.sub.2 and R.sub.3 may be bonded to form a cyclic structure, the said derivative containing the ether bond preferably in a degree of substitution of from 0.01 from 0.1, to the said papermaking stock in an amount of from 0.05 to 5.0% by weight of the cellulose fiber or the total of the said fiber and the inorganic filler in the said stock, as well as the said starch ether derivative of the formula (I) and a method for preparation of the said derivative.

Papermaking method

Disclosed are a papermaking method comprising the steps of sheet-formation of an aqueous papermaking stock which contains a cellulose fiber or the said fiber and an inorganic filler, dewatering and drying, characterized by the addition of a starch ether derivative of a general formula (I): ##STR1## where St-O represents a starch molecule residue, R.sub.1, R.sub.2 and R.sub.3 independently represent an alkyl group having from 1 to 18 carbon atoms or a benzyl group, provided that two or more of these R.sub.1, R.sub.2 and R.sub.3 must not be a benzyl group or an alkyl group having from 5 to 18 carbon atoms at the same time, and any two of these R.sub.1, R.sub.2 and R.sub.3 may be bonded to form a cyclic structure, the said derivative containing the ether bond preferably in a degree of substitution of from 0.01 to 0.1, to the said papermaking stock in an amount of from 0.05 to 5.0% by weight of the cellulose fiber or the total of the said fiber and the inorganic filler in the said stock, as well as the said starch ether derivative of the formula (I) and a method for preparation of the said derivative.

A compound having the formula: ##STR1## wherein R is a hydroxyl-protecting group, X is a hydrogen atom, CO.sub.2 R' (wherein R' is a hydrogen atom or an alkyl group having from 1 to 7 carbon atoms, or CO.sub.2 R' is a salt of CO.sub.2 H), or a group of the formula: ##STR2## and when X is a hydrogen atom, Y is CO.sub.2 R' (wherein R' is as defined above) or a group of the formula: ##STR3## and when X is CO.sub.2 R' or the group of the formula (i), Y is a hydrogen atom.

Optically active bicyclo carboxylic acids and their derivatives

2-Phenylpropoionic acid ester of Formula (I): ##STR1## wherein R represents p-nitrophenyl group, .beta.-naphthyl group or 2-(.beta.-naphthyl)ethyl group. Optical resolution of the above is carried out by preferential crystallization by seeding either one of the optical isomers into a super-saturated solution of a racemic modification thereof or a mixture of the optical isomers thereof. The efficiency of the optical resolution can be increased by optional addition of a recemizing agent comprising a strongly basic amine or an alcholate.

2-phenylpropionic acid esters, method for optical resolution thereof and

A process for preparing d-.alpha.-(6-methoxy-2-naphthyl)propionic acid, which comprises hydrolyzing an ester of d-.alpha.-(6-methoxy-2-naphthyl)propionic acid in an aqueous solution containing a basic catalyst.

Process for preparing D-.alpha.-(6-methoxy-2-naphtyl) propionic acid

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Funabashi, Japan

Yasuhiro Takahashi