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 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 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: 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: 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: 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.