Abstract: Disclosed are novel fluoran compounds represented by the formula (I): ##STR1## wherein R.sub.1 and R.sub.2 are different groups selected from cyclohexyl, n-butyl and isobutyl, e.g., in the form of crystals characterized by a specific X-ray diffraction diagram; crystalline toluene adducts thereof; and recording materials containing these fluoran compounds.

Abstract: A heat-sensitive recording material comprising a color forming, electron donating compound and a salicylic acid derivative represented by the formula (1): ##STR1## wherein X.sub.1 and X.sub.2 are a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group, an aryl group or a halogen atom, Y.sub.1 and Y.sub.2 are an oxygen atom or a sulfur atom, R.sub.1 is a hydrogen atom, an alkyl group, an aralkyl group or an aryl group , and R.sub.2 is an alkyl group, an alkenyl group, an aralkyl group or an aryl group, and/or a metal salt of the salicylic acid derivative as an electron accepting compound, is disclosed.

Abstract: Disclosed are a crystal and crystalline solvate of a fluoran compound represented by the formula ##STR1## wherein R.sub.1 is ##STR2## and which are useful as chromogenic compounds in recording materials such as pressure-sensitive and heat-sensitive recording materials, a process for preparation of said crystal and said crystalline solvate, and recording materials comprising said crystal or said crystalline solvate.

Abstract: Disclosed are a crystal of a fluoran compound having the formula comprising exhibiting high peaks at diffraction angles (2.theta.) of 7.5.degree. and 17.0.degree. and relatively high peaks at diffraction angles (2.theta.) of 15.1.degree., 19.1.degree., 21.5.degree. and 25.3.degree. in an X-ray diffraction diagram by the CU-K.alpha. beam and a crystal of a fluoran compound having the formula (II) comprising exhibiting high peaks at diffraction angles (2.theta.) of 5.5.degree. and 19.2.degree. in an X-ray diffraction diagram by the CU-K.alpha. beam, which is useful as a color forming compound in recording materials.

Abstract: Disclosed are novel crystal of the fluoran compound represented by the formula (I) ##STR1## ,characterized by a specific X-ray diffraction diagram; preparation process thereof; and recording materials comprising the crystal.

Abstract: Disclosed is a polarizing film comprising a hydrophobic polymer containing a dichroic organic colorant in an oriented state which is characterized in that the dichroic organic colorant is substantially insoluble in water, organic solvents and liquid crystals and the dichroic ratio of the colorant is not less than 7 when it is measured with the film obtained by blending the colorant intimately with polyethylene terephthalate, melting the resulting blend and forming it into a film. This polarizing film has exceptionally excellent moisture resistance and thermal resistance.

Abstract: Disclosed are novel crystal of the fluoran compound represented by the formula (I) ##STR1## , characterized by a specific X-ray diffraction diagram; preparation process thereof; and recording materials comprising the crystal.

Abstract: A reversible thermochromic material, preferably in the form of a microcapsule, comprising:(a) an electron donative color former;(b) a sulfide, sulfoxide or sulfone containing a hydroxy phenyl radical; and(c) a chemical compound selected from alcohols, esters, ethers, ketones, carboxylic acids or acid amides,chromatizes very brightly and in a dense color, generates a change of chromic hue (colored - colorless) within a narrow temperature range and provides a stable thermochromatism on a long term basis.

Abstract: Heat-sensitive recording materials contain an electron-donating chromogenic compound and an electron-attracting compound. The recording materials also contain at least one compound represented by the following formula: ##STR1## wherein R.sub.1 and R.sub.3 mean a hydrogen atom or an alkyl, aralkyl or aryl group, R.sub.2 and R.sub.4 denote an alkyl, alkenyl, aralkyl or aryl group, X.sub.1, X.sub.2, Y.sub.1 and Y.sub.2 stand for an oxygen or a sulfur atom, and --Z.sub.1 -- and --Z.sub.2 -- are a specific aromatic group. Also provided are phenol compounds represented by the following formula: ##STR2## wherein R.sub.1, R.sub.2, X.sub.1 and Y.sub.1 have the same meanings as defined above; R.sub.5 and R.sub.6 are a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group; p and q stand for an integer of 1-4; R.sub.5 and R.sub.6 may be either the same or different when p and q represent an integer of 2 or greater; and --Z.sub.3 -- means a specific divalent group.

Abstract: Disclosed are a crystal and crystalline solvate of a fluoran compound represented by the formula ##STR1## wherein R.sub.1 is ##STR2## and which are useful as chromogenic compounds in recording materials such as pressure-sensitive and heat-sensitive recording materials, a process for preparation of said crystal and said crystalline solvate, and recording materials comprising said crystal or said crystalline solvate.

Abstract: Heat-sensitive recording paper which employs as a chromogenic compound a novel fluoran compound represented by the formula: ##STR1## and prepared reacting a benzoic acid derivative of the formula: ##STR2## with a diphenylamine derivative of the formula: ##STR3## wherein R is a lower alkyl group have excellent stability.

Abstract: Disclosed are novel fluoran compounds represented by the formula (I): ##STR1## wherein R.sub.1 and R.sub.2 are different groups selected from cyclohexyl, n-butyl and isobutyl, e.g., in the form of crystals characterized by a specific X-ray diffraction diagram; crystalline toluene adducts thereof; and recording materials containing these fluoran compounds.

Abstract: Disclosed are a crystal of a fluoran compound having the formula (I) comprising exhibiting high peaks at diffraction angles (2.theta.) of 7.5.degree. and 17.0.degree. and relatively high peaks at diffraction angles (2.theta.) of 15.1.degree., 19.1.degree., 21.5.degree. and 25.3.degree. in an X-ray diffraction diagram by the Cu-K.alpha. beam and a crystal of a fluoran compound having the formula (II) comprising exhibiting high peaks at diffraction angles (2.theta.) of 5.5.degree. and 19.2.degree. in an X-ray diffraction diagram by the Cu-K.alpha. beam, which is useful as a color forming compound in recording materials.

Abstract: Novel fluoran compounds represented by the formula (I): ##STR1## wherein R.sup.1 is an alkyl group having from 1 to 4 carbon atoms, preparation process of the fluoran compounds, and a heat-sensitive and a pressure-sensitive recording material comprising the fluoran compound, are disclosed.

Abstract: Polycarbonate granules are produced by adding a solution of polycarbonate in an organic solvent to a suspension composed of water, an anti-solvent for polycarbonate and polycarbonate powder with stirring while evaporating and removing the organic solvent for polycarbonate added to the suspension. The procedure may be effected in the presence of a stabilizing agent for polycarbonate. The resulting polycarbonate granules are easy in handling, and free from fine powder, have high bulk density, large particle size and uniform quality, and can be directly molded.

Abstract: Disclosed are a novel fluoran compound represented by the formula (I): ##STR1## and a heat-sensitive recording paper which is obtained by using the fluoran compound as a chromogenic compound and is excellent in preserving stability.

Abstract: Disclosed are novel crystal of the fluoran compound represented by the formula ##STR1## , characterized by a specific X-ray diffraction diagram; preparation process thereof; and recording materials comprising the crystal.

Abstract: A ferroelectric liquid crystal is formed by incorporating, as the main component, a predetermined amount of a ferroelectric liquid crystal having a specific naphthalene ring structure into conventional liquid crystals. This liquid crystal composition has a broad driving temperature range and in particular, can be effectively driven even in a low-temperature region. Moreover, this liquid crystal composition has a high orientation uniformity, a high memory stability, and a high contrast ratio.

Abstract: Novel fluoran compounds represented by the formula (I): ##STR1## wherein R.sup.1 is an alkyl group having from 1 to 4 carbon atoms, preparation process of the fluoran compounds, and a heat-sensitive and a pressure-sensitive recording material comprising the fluoran compound, are disclosed.

Abstract: The present invention is directed to optically active compounds each containing a naphthalene skeleton, and to liquid crystal compositions which contain the aforesaid optical active compounds, these compositions being suitable for ferroelectric liquid crystal devices having excellent photostability and chemical stability and having a rapid responsivity.