Mitsubishi Rayon Company, Limited

Yoshitaka Kageyama

Keiichi Sakashita

Jun Nakauchi

Seiji Hayashi

Kenji Mori

Yoshihiro Sako

Tetsuya Ikemoto

Mioko Uematsu

Mitsuo Hamada

Shunsuke Minami

Tokihiko Masuzawa

Takahiro Okuya

Yoshihiko Sako

Takeaki Amakawa

Norizou Tomita

This invention relates to an acrylonitrile-based precursor fiber for carbon fiber which is prepared from an acrylonitrile-based copolymer containing 96.0 to 98.5% by weight of acrylonitrile units, and which is characterized by a tensile strength of not less than 7.0 cN/dtex, an elastic modulus in tension of not less than 130 cN/dtex, an iodine adsorption of not greater than 0.5% by weight based on the weight of the fiber, a degree of crystal orientation (&pgr;) of not less than 90% as determined by wide-angle X-ray analysis, and a degree of variation in tow fineness of not greater than 1.0%. This precursor fiber has a high strength, a high elastic modulus, a high degree of denseness, a high degree of orientation, and a low degree of variation in tow fineness, and can hence be used to form a high-quality carbon fiber inexpensively by oxidation for a shorter period of time.

Acrylonitrile-based precursor fiber for carbon fiber and method for production thereof

Optical active compounds which are chemically stable, are not colored, have a good optical stability, and which give a liquid crystal composition having a large spontaneous polarization when the compound is incorporated, are provided. The optical active compound have an asymmetric carbon atom fixed by a .delta.-valerolactone ring and the permanent dipole moment derived from the carboxylic group is fixed by the .delta.-valerolactone ring and two alkyl groups which can be regarded as a part of a measogen.

Optically active compound having a .delta.-valerolactone ring and liquid

An optically active compound represented by the formula: ##STR1##

Optical active compound and liquid crystal composition

Disclosed is an optically active substance represented by the formula: ##STR1## wherein m is an integer of 1 to 14, Y is ##STR2## R is --C.sub.n H.sub.2n+1, --OC.sub.n H.sub.2n+1, --OCOC.sub.n H.sub.2n+1 or --COOC.sub.n H.sub.2n+1 (in which n is an integer of 1 to 18), each of the asterisked carbon atoms is an asymmetric carbon atom, X a single bond, --CO.sub.2 --, or --OCO--, and A.sub.1 and A.sub.2 is hydrogen, fluorine, chlorine, bromine, cyano or methoxy.

Optically active substance and liquid crystal composition comprising same

Disclosed is an optically active compound represented by the formula: ##STR1## or a single bond, Z stands for a hydrogen atom, a halogen atom or a cyano group, R.sub.1 stands for an alkyl group or fluoroalkyl group having 1 to 18 carbon atoms, R.sub.2 stands for an alkyl group or alkoxy group having 1 to 18 carbon atoms, and *C stands for the asymmetric carbon atom. This compound is used as a ferroelectric liquid crystal or an additive to a ferroelectric liquid crystal.

Optically active compound and liquid crystal composition

An optically active compound having a .delta.-valerolactone ring which is a ferroelectric liquid crystal and is represented by the following general formula (I): ##STR1## wherein m is an integer of from 1 to 8, Z is a group represented by the following formula: ##STR2## in which each of l and k is a number of 1 or 2 and l and k satisfy the requirement of 2.ltoreq.(l+k).ltoreq.3,

Optically active compound having XI-valerolactone ring and liquid

Disclosed is a mesomorphic compound having a .beta.-hydroxycarboxyl group as the chiral source, which is represented by the formula: ##STR1## wherein m and n are integers of from 1 to 18, X.sub.1 and X.sub.2 independently represent fluorine, chlorine or hydrogen, Y represents ##STR2## or --O--, Z represents a direct bond, ##STR3## --CH hd 2O-- or --OCH.sub.2 --, and * indicates the asymmetric carbon. The mesomorphic compound is valuable as a ferroelectric liquid crystal or an additive to a ferroelectric liquid crystal or to a compound showing the SmC phase and having no chiral group.

Mesomorphic compound having .beta.-hydroxycarboxyl group as chiral

Disclosed is an .alpha.-methylcinnamic acid ester derivative represented by the formula: ##STR1## wherein n is an integer of from 5 to 18, R.sub.1 represents an optically active group of the formula ##STR2## in which m is an integer of from 1 to 5 and *C represents an asymmetric carbon atom, and R.sub.2 represents ##STR3##

Alpha-methylcinnamic acid ester derivative and liquid crystal composition

An edge-lighting type light diffuser is disclosed which has a plane of light incidence, a light transmitting means and a plane of light emission. The light transmitting means is composed of a laminate of a plurality of light-transmissible plates. This structure provides a light diffuser capable of uniform plane illumination usable for sign boards, large-sized display devices, display devices for various types of machinery, and liquid crystal devices.

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Tokyo, Japan

Yoshitaka Kageyama