Abstract: There are provided a photocurable composition capable of being readily cured by irradiation of ultraviolet rays and a cured product of the photocurable composition, as well as a coating composition and a coating film obtained from the coating composition. The cured product exhibits a high refractive index, a less discoloration and an excellent transparency. The present invention relates to a photocurable composition comprising (A) an episulfide compound containing a thiirane ring; and (B) a photo-base generator represented by the general formula (1): wherein Ar is phenyl, etc.; R is an alkyl group, etc.; —A+ is an ammonium ion; and X? is a borate anion, etc., and a coating composition comprising the photocurable composition and (C) a modified silicone oil, as well as a cured product and a coating film obtained from these compositions.

Abstract: A vicinal dithiol is produced by the reaction of an episulfide compound having at least one thiirane ring in its molecule and a thiocarboxylic S-acid.

Abstract: There is provided a coating composition having a good wetting property which is capable of forming a coating film exhibiting a high refractive index, a less discoloration, and excellent transparency and uniformity when polymerized and cured. The present invention relates to a coating composition comprising (A) 100 parts by weight of a thiirane ring-containing compound, (B) 0.0001 to 10 parts by weight of a catalyst for accelerating polymerization of the thiirane ring-containing compound, and (C) 0.005 to 4 parts by weight of a modified silicone oil; a coating film produced from the composition; and an optical product provided with the coating film.

Abstract: An optically active compound of the general formula (1), wherein n is an integer of 4 to 8, X is -Ph-COO-Ph-Ph-, -Ph-Ph-COO-Ph-, -Ph-OC-Ph-Ph-, -Ph-Ph-OC-Ph-, -Ph-Ph-Ph-, -Cy-COO-Ph-Ph-, -Ph-Ph-OC-Cy-, -Ph-OC-Ph-COO-Ph-, -Ph-OC-Cy-COO-Ph-, -Ph-OC-Np-COO-Ph-, -Np-OC-Ph- or -Ph-COO-Np- in which -Ph- is a 1,4-phenylene group, -Cy- is a trans-1,4-cyclohexylene group and -Np- is a 2,6-naphthylene group, and C* is an asymmetric carbon, and a nematic liquid crystal composition containing the above optically active compound. According to the present invention, there is provided a nematic liquid crystal composition containing the optically active compound having a helical twisting power (HTP) of 10 or more and giving a chiral dopant for a nematic liquid crystal, which chiral dopant has a property that the pitch of its induced helix decreases in length with an increase in temperature.

Abstract: A process for producing a hard-coated optical material. In the process, the hard coat is formed on the surface of plastic substrate after dipping the plastic substrate in an acidic substance without forming an intermediate layer such as a primer layer.

Abstract: A vicinal dithiol is produced by the reaction of an episulfide compound having at least one thiirane ring in its molecule and a thiocarboxylic S-acid.

Abstract: An optically active compound containing 5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-bi-2-naphthol of the general formula (1) as an asymmetric source, wherein n is an integer of 1 to 10, Y is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a phenyl group, a phenyl group substituted with an alkyl group having 1 to 5 carbon atoms or a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms, X is a single bond (—), —OOC— or —OCH2—, and each of A and B is a substituent formed by specifically combining rings selected from cyclohexane, benzene, pyrimidine, naphthalene, dioxane, etc.

Abstract: An optically active compound of the general formula (1) useful as a chiral dopant and use thereof, wherein each of m and n is independently an integer of 4 to 8, A is —Ph—COO—Ph—, —Ph—Ph—COO—, —Cy—COO—Ph—, —Ph—OOC—Ph—COO—, —Ph—OOC—Cy—COO—, —Ph—OOC—Np—COO— or —Np—OOC— in which —Ph— is a 1,4-phenylene group, —Cy— is a trans-1,4-cyclohexylene group and —Np— is a 2,6-naphtylene group, and C* is an asymmetric carbon atom. Having a helical twisting power (HTP) of at least 9 and having a property that the helical pitch induced decreases with an increase in temperature, the optically active compound of the present invention has an excellent value as a chiral dopant for a nematic liquid crystal.

Abstract: An optically active compound of the following general formula (1), wherein A is —C≡C— or —COO—, each of R1 and R2 is independently CnH2n+1—, (C2H5)2CHCH2C*H(CH3)OOC—, CmH2m+1C*H(CH3)OOC— or C6H5C*H(CH3)OOC— in which n is an integer of 2 to 5, m is an integer of 5 to 9, C6H5— is phenyl group, and C* is an asymmetric carbon, provided that there is no case where R1 and R2 are together CnH2n+1— or C6H5C*H(CH3)OOC— and that when both R1 and R2 are CmH2m+1C*H(CH3)OOC—, m in CmH2m+1C*H(CH3)OOC— represented by R1 and m in CmH2m+1C*H(CH3)OOC— represented by R2 may be different integers. The optically active compound of the present invention is excellently valuable as a chiral dopant since it has properties that its helical twisting power (HTP) is at least 9, that a helical pitch induced decreases with an increase in temperature and further that its birefringence (&Dgr;n) is large.

Abstract: An optically active compound containing 5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-bi-2-naphthol of the general formula (1) as an asymmetric source, 1

Abstract: An optically active compound of the following general formula (1) useful as a chiral dopant, and use thereof, wherein each of X and Y is independently a hydrogen atom or a fluorine atom, R is (C2H5)2CHCH2C*H(CH3)— or Ph—C*H(CH3)—, A is —Ph(W)—COO—Ph—, —Ph—Ph—COO—, —Cy—COO—Ph—, —Ph(W)—OOC—Ph—COO—, —Ph(W)—OOC—Cy—COO—, —Ph(W)—OOC—Np—COO— or —Np—OOC—, in which Ph— is a phenyl group, —Ph— is a 1,4-phenylene group, —Ph(W)— is —Ph— or monofluoro substituted —Ph—, Cy— is a trans-1,4-cyclohexylene group and —Np— is a 2,6-naphthylene group, and C* is an asymmetric carbon.

Abstract: An optically active compound of the general formula (1) useful as a chiral dopant, and use thereof for a liquid crystal composition, the above optically active compound having a remarkably large helical twisting power (HTP) of as large as 50 or more and having a property that the helical pitch induced decreases in length with an increase in temperature, so that the optically active compound has an excellent value as a chiral dopant for a nematic liquid crystal.

Abstract: An optically active compound of the general formula (1) useful as a chiral dopant, and use thereof for a liquid crystal composition, 1

Abstract: Optically active compounds of the following general formula (1) useful as chiral dopant, wherein n is an integer of 0 to 5, provided that when n is 0, A is a single bond (—) and that when n is 1 to 5, A is a single bond (—), —O—, —COO—, —Cy— or —Cy—COO— in which —Cy— is a trans-1,4-cyclohexylene group, each of X and Y is independently a hydrogen atom or a fluorine atom, B is a single bond (—), —COO—, —COO—Ph— or —Ph—COO— in which —Ph— is a 1,4-phenylene group, and C* is an asymmetric carbon. The chiral dopant of the present invention have a high helical twisting power of at least 9 and suitably have a feature that the helical pitch induced by them decreases in length with an increase in temperature so that they are advantageous for use in a nematic liquid crystal composition.

Abstract: An optically active compound of the general formula (1) useful as a chiral dopant and use thereof, 1

Abstract: An optically active compound of the following general formula (1), 1

Abstract: An optically active compound of the following general formula (1) useful as a chiral dbpant, and use thereof, 1

Abstract: Optically active compounds of the following general formula (1) useful as chiral dopant, 1

Abstract: A liquid crystal composition includes (1) an anti-ferroelectric liquid crystal compound of formula (1) and (2) a ferrielectric liquid crystal compound or racemic compound thereof. The composition ratio of (1) to (2) is in the range extending from a value which extends from within 5 mol % of the boundary compositional ratio on the anti-ferroelectric phase side and to within 25 mol % of the boundary compositional ratio on the ferrielectric phase side. The boundary compositional ratio is obtained on the basis of a liquid crystal phase diagram prepared on the basis of conoscopic image observations obtained by changing the mixing ratio of (1) and (2). The liquid crystal composition has the following properties: (b) an optical response in a positive voltage region and a negative voltage region and free or substantially free of hysteresis; and (c) excellent alignment stability.

Abstract: A fluorine-substituted compound of the following general formula (1) or (2), and a ferrielectric liquid crystal composition comprising the above compound and a specific ferrielectric liquid crystal compound, wherein, in the formula (1), each of X1 and X2 is a hydrogen atom, or one of them is a hydrogen atom and the other is a fluorine atom, p is an integer of 0 to 3 and q is an integer of 1 to 3, and in the formula (2), each of X1 and x2 is a hydrogen atom, or one of them is a hydrogen atom and the other is a fluorine atom, p is an integer of 1 to 3 and q is an integer of 1 to 3.