Abstract: A heat sensitive recording material is described, which has on a support a heat sensitive coloring layer containing (a) an electron-donating colorless dye, (b) an electron-accepting compound, and (c) at least one ether compound represented by formula (I) or (II) ##STR1## wherein X represents a hydrogen atom, a halogen atom, an alkyl group containing not more than 6 carbon atoms, or an alkoxy group containing not more than 6 carbon atoms; Y represents a hydrogen atom, a halogen atom, an alkyl group containing not more than 6 carbon atoms, or an alkoxy group containing not more than 6 carbon atoms; and R represents a hydrogen atom or an alkyl group containing not more than 18 carbon atoms.

Abstract: A heat-sensitive recording material is disclosed. The material is comprised of a support base having a color forming layer positioned thereon. The layer is comprised of an electron donating colorless dye, an electron accepting compound, a naphthol derivative, and a urea derivative and/or a urethane derivative. The recording material can provide good color density and color sensitivity.

Abstract: A heat-sensitive recording material is disclosed. The material is comprised of an electron donating dye, electron accepting compound and a sensitivity improving agent thereon. The sensitivity improving agent is a compound represented by the general formula (I) ##STR1## wherein R.sub.1 and R.sub.2 independently represent an alkyl group, an aralkyl group, an aryl group, an alkoxy group having 12 or less carbon atoms or a halogen atom, and m and n independently represent 0 or an integer of 5 or less. By including the sensitivity improving agent, it is possible to obtain a heat-sensitive recording material which produces an image of high color density.

Abstract: A heat-sensitive recording paper which is comprised of a support base having a heat-sensitive color forming layer thereon is disclosed. The layer contains a colorless or faint color electron donating dye, a bisphenol and a straight chain fatty acid amide. The recording sensitivity of the paper is greatly increased by incorporating a phenol derivative having the general formula ##STR1## wherein R is an alkyl group or an aralkyl group and Y represents a phenyl group, an alkyl group, a cycloalkyl group or a halogen atom.

Abstract: A heat-sensitive recording paper having a heat-sensitive color-forming layer on the glossy surface of a support base comprised of raw paper manufactured with a Yankee machine is disclosed. The paper has improved surface smoothness and back side roughness because the raw paper used was manufactured with the Yankee machine. The heat-sensitive recording paper produces an image with increased density without increased fogging.

Abstract: A heat-sensitive recording material comprising a heat-sensitive color forming layer on a base is disclosed. The color forming layer contains an electron donating colorless dye and an organic acid to which a heat-fusible substance having a melting point in the range of from 60.degree. to 150.degree. C. is fusion-bonded. A process for producing such recording material by applying to a base a coating solution containing a developer for heat-sensitive recording is also disclosed. The developer is prepared by the steps of dispersing in a dispersion medium a heat-fusible substance having a melting point in the range of from 60.degree. C. to 150.degree. C. and an organic acid, heating the resulting dispersion under conditions that form a turbulent flow, and cooling the heated dispersion to ordinary temperatures.

Abstract: A heat-sensitive recording paper comprising a paper support having coated thereon a heat-sensitive recording layer, which is surface-treated by passing said recording paper, after drying said heat-sensitive recording layer, through a pressure-applying member comprising a combination of a metal roll and an elastic roll of from 70 to 90 in Shore hardness wherein said heat-sensitive layer surface is contacted with said metal roll.

Abstract: A heat-sensitive recording paper which has on a paper support a heat-sensitive recording layer having received a surface treatment in such a state that the recording paper comes to contain moisture in a proportion ranging from 5 wt % to 12 wt % by drying after the coating of the heat-sensitive recording layer. The surface treatment is effected by passing the recording paper through a pressure applying means. The pressure applying means is constructed by metal roller heated up to a temperature of 40.degree. C. to 60.degree. C. and an elastic roller (made preferably of hard rubber). The recording layer is brought into a face-to-face contact with the metal roller.

Abstract: Recording members having excellent light resistance are obtained by using as a dye precursor specific diarylaminofluoran compounds.

Abstract: A heat-sensitive recording paper is disclosed having improved heat-transmission efficiency between a recording element and the heat-sensitive recording paper. The disclosed heat-sensitive recording paper includes a support base paper having an aqueous-sensitive developable layer coated thereon. In the base paper used, the value obtained by dividing Stockigt sizing degree by a square number of meter areal weight is 3.times.10.sup.-3 (S.m.sup.4 /g.sup.2) or more and Bekk smoothness of 90 seconds or more. The aqueous heat-sensitive developable layer coated on the surface of the base support includes a dispersion of particles having a volume average particle size of 8 .mu.m or less, said layer being coated on the surface of the base support to a thickness of 5 to 10 .mu.m.

Abstract: A heat-sensitive recording material comprising a heat-sensitive color forming layer on a base is disclosed. The color forming layer contains an electron donating colorless dye and an organic acid to which a heat-fusible substance having a melting point in the range of from 60.degree. to 150.degree. C. is fusion-bonded. A process for producing such recording material by applying to a base a coating solution containing a developer for heat-sensitive recording is also disclosed. The developer is prepared by the steps of dispersing in a dispersion medium a heat-fusible substance having a melting point in the range of from 60.degree. C. to 150.degree. C. and an organic acid, heating the resulting dispersion under conditions that form a turbulent flow, and cooling the heated dispersion to ordinary temperatures.

Abstract: A heat-sensitive recording material comprising a base and one or more heat-sensitive color-forming layers containing an electron donating colorless dye and an electron accepting organic compound is disclosed, wherein at least one of said color-forming layers contains a urea derivative having a least 7 carbon atoms or a urethane derivative having at least 8 carbon atoms.

Abstract: Recording members having excellent light resistance are obtained by using as a dye precursor specific diarylaminofluoran compounds.

Abstract: A fluoran compound represented by the formula: ##STR1## wherein R.sub.1 and R.sub.2 each represents an alkyl group containing up to 18 carbon atoms, R.sub.3 represents an alkyl group, a halogenated alkyl group, or an alkoxyalkyl group containing up to 18 carbon atoms, and X represents a halogen atom, a process for preparing such fluoran compound and a pressure-or heat-sensitive recording sheet comprising such fluoran compound as a color former, which are capable of providing black images having excellent stability, e.g., with respect to light.

Abstract: A heat-sensitive recording sheet which comprises a support, a white or light-colored pigment coating layer having an oil absorption determined by JIS K5101 of 75 ml/100 g or more on the support, and a heat-sensitive color forming layer comprising an electron donor colorless dye and an electron acceptor compound on the coating layer.

Abstract: A heat-sensitive recording sheet comprising a support and a recording layer containing an electron donating colorless dye and a compound represented by the following formula: ##STR1## wherein R represents an alkyl group containing 2 to 12 carbon atoms.

Abstract: A heat-sensitive recording paper comprising a base paper having a hot water extraction pH of about 6 to 9 having provided thereon a heat-sensitive recording layer containing an electron donating colorless dye and an electron accepting acidic material.

Abstract: A recording sheet comprising a support having thereon a layer of a color developer capable of forming a developed color image in the presence of a color former, wherein the color developer layer contains (1) a dimer of a compound of the formula (I): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, each represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and n is an integer of 1 to 4, as a color developer, and (2) an oil adsorptive inorganic pigment.

Abstract: A thermochromic material, and a heat sensitive recording material containing the same, comprising a substantially colorless electron donating color former capable of forming a color upon reacting with an electron accepting acid compound and a compound represented by the general formulaHOArCOORwherein R represents an organic group having 1 to about 10 carbon atoms and Ar represents an aromatic nucleus.

Abstract: A coated paper having a moisture and water-proof coating thereon is produced by coating a paper substrate with an aqueous emulsion containing a synthetic rubber latex and a wax emulsion in an amount of the solid wax of 5 to 200 parts by weight per 100 parts by weight of the solid synthetic rubber and, then, drying the coated paper at a temperature the same as or higher than the melting point of the wax. The resultant paper is highly capable of repulping.