Abstract: A cutting tool is a cutting tool including: a base; and a coating disposed on the base, wherein the coating includes a first layer, wherein the first layer is composed of ?-Al2O3, a thickness of the first layer is 2 ?m or more and 15 ?m or less, on a cross section along a normal line of an interface between the base and the coating, a ratio N2/N1 is 0.60 or more, and on the cross section along the normal line of the interface between the base and the coating, a ratio N4/N3 and the ratio N2/N1 satisfy a relationship of a Formula 1.

Abstract: A cutting tool comprising a base material and a coating disposed on the base material, wherein the coating comprises a hard particle layer, the hard particle layer is formed from a plurality of hard particles consisting of titanium, silicon, carbon, and nitrogen, the hard particle layer comprises a first region and a second region, a composition of the first region is Ti(1-Xb)SiXbCN, a composition of the second region is Ti(1-Xs)SiXsCN, the Xs and the Xb satisfy relationships of Xb?Xs?0.01 and 0<Xs<Xb?0.10, the hard particles have a cubic crystal structure, and in the hard particles, a concentration of the silicon changes periodically along a first direction going from the first main surface to the second main surface.

Abstract: A cutting tool comprising a base material and a coating disposed on the base material, wherein the coating comprises a hard particle layer, the hard particle layer is formed from a plurality of hard particles consisting of titanium, silicon, carbon, and nitrogen, the hard particle layer comprises a first region and a second region, a composition of the first region is Ti(1-Xb)SiXbCN, a composition of the second region is Ti(1-Xs)SiXsCN, the Xs and the Xb satisfy relationships of Xb?Xs?0.01 and 0<Xs<Xb?0.10, the hard particles have a cubic crystal structure, and in the hard particles, a concentration of the silicon changes periodically along a first direction going from the first main surface to the second main surface.

Abstract: A cutting tool comprising a base material and a coating disposed on the base material, wherein the coating comprises a hard particle layer, the hard particle layer is formed from a plurality of hard particles consisting of titanium, silicon, carbon, and nitrogen, the hard particle layer comprises a first region and a second region, a composition of the first region is Ti(1-Xb)SiXbCN, a composition of the second region is Ti(1-Xs)SiXsCN, the Xs and the Xb satisfy relationships of Xs-Xb?0.01 and 0<Xb<Xs?0.10, the hard particles have a cubic crystal structure, and in the hard particles, a concentration of the silicon changes periodically along a first direction going from the first main surface to the second main surface.

Abstract: A cutting tool including a substrate and a coating film disposed on the substrate, wherein the cutting tool includes: a rake face, a flank face contiguous to the rake face; and a cutting edge region composed of a boundary part between the rake face and the flank face, wherein the coating film includes a TiSiCN layer, the TiSiCN layer has: a first TiSiCN layer positioned in the rake face; and a second TiSiCN layer positioned in the cutting edge region, the first TiSiCN layer has a composition of Ti(1-Xr)SiXrCN, the second TiSiCN layer has a composition of Ti(1-Xe)SiXeCN, and the Xr and the Xe each represent 0.010 or more and 0.100 or less, and satisfy a relationship of Xr?Xe?0.003.

Abstract: A cutting tool including a substrate and a coating film disposed on the substrate, wherein the cutting tool includes: a rake face, a flank face contiguous to the rake face; and a cutting edge region composed of a boundary part between the rake face and the flank face, wherein the coating film includes a TiSiCN layer, the TiSiCN layer has: a first TiSiCN layer positioned in the rake face; and a second TiSiCN layer positioned in the cutting edge region, the first TiSiCN layer has a composition of Ti(1-Xr)SiXrCN, the second TiSiCN layer has a composition of Ti(1-Xe)SiXeCN, and the Xr and the Xe each represent 0.010 or more and 0.100 or less, and satisfy a relationship of Xr?Xe?0.003.

Abstract: A cutting tool including a substrate and a coating film disposed on the substrate, wherein the cutting tool includes: a rake face; a flank face contiguous to the rake face; and a cutting edge region composed of a boundary part between the rake face and the flank face, wherein the coating film includes a TiSiCN layer, the TiSiCN layer has: a first TiSiCN layer positioned in the rake face; and a second TiSiCN layer positioned in the cutting edge region, the first TiSiCN layer has a composition of Ti(1-Xr)SiXrCN, the second TiSiCN layer has a composition of Ti(1-Xe)SiXeCN, and the Xr and the Xe each represent 0.010 or more and 0.100 or less, and satisfy a relationship of Xe-Xr?0.003.

Abstract: A cutting tool includes a substrate and a coating film, wherein the coating film has a first layer formed from a plurality of hard grains, the hard grains are made of TiSiCN having a cubic crystal structure, the hard grains have a lamellar structure in which a layer having a relatively high silicon concentration and a layer having a relatively low silicon concentration are alternately stacked, and a maximum value of percentage of number ASi of silicon atoms to a sum of the number ASi of silicon atoms and number ATi of titanium atoms in a grain boundary region between the hard grains, {ASi/(ASi+ATi)}×100, is larger than an average value of percentage of number BSi of silicon atoms to a sum of the number BSi of silicon atoms and number BTi of titanium atoms in the first layer, {BSi/(BSi+BTi)}×100.

Abstract: A cutting tool includes a substrate and a coating film, wherein the coating film has a first layer formed from a plurality of hard grains, the hard grains are made of TiSiCN having a cubic crystal structure, the hard grains have a lamellar structure in which a layer having a relatively high silicon concentration and a layer having a relatively low silicon concentration are alternately stacked, and a maximum value of percentage of number ASi of silicon atoms to a sum of the number ASi of silicon atoms and number ATi of titanium atoms in a grain boundary region between the hard grains, {ASi/(ASi+ATi)}×100, is larger than an average value of percentage of number BSi of silicon atoms to a sum of the number BSi of silicon atoms and number BTi of titanium atoms in the first layer, {BSi/(BSi+BTi)}×100.

Abstract: A novel 4-acylaminopyridine derivative represented by the following formula (I) is disclosed. ##STR1## The 4-acylaminopyridine derivative of the present invention is useful as a medicine for treating disturbances of memory such as senile dementia and Alzheimer's disease, since it has an action of directly activating malfunctioned cholinergic neuron.

Abstract: A novel 4-acylaminopyridine derivative represented by the following formula (I) is disclosed. ##STR1## The 4-acylaminopyridine derivative of the present invention is useful as a medicine for treating disturbances of memory such as senile dementia and Alzheimer's disease, since it has an action of directly activating malfunctioned cholinergic neuron.

Abstract: A novel 4-acylaminopyridine derivative represented by the following formula (I) is disclosed. ##STR1## The 4-acylaminopyridine derivative of the present invention is useful as a medicine for treating disturbances of memory such as senile dementia and Alzheimer's disease, since it has an action of directly activating malfunctioned cholinergic neuron.