Abstract: A method for producing polytetrafluoroethylene, which includes polymerizing tetrafluoroethylene in an aqueous medium in the presence of a nucleating agent and a hydrocarbon anionic surfactant to obtain polytetrafluoroethylene. A total amount of the nucleating agent and the hydrocarbon anionic surfactant at the initiation of polymerization is more than 50 ppm based on the aqueous medium.

Abstract: A coated tool includes a base and a coating layer located on the base. The coating layer includes a first layer having a thickness of 1 ?m or more located near the base, and a second layer including Al2O3 particles which is in contact with the first layer and is located more away from the base than the first layer. A difference (A2?A1) between an erosion ratio A2 in the second layer and an erosion ratio A1 in the first layer is 0.60 to ?0.30 ?m/g. The erosion ratio is obtained by collision of a liquid A in which 3 mass % of spherical Al2O3 particles having a mean particle diameter of 1.1-1.3 ?m is dispersed in pure water. A cutting tool includes a holder which includes a pocket, and the coated tool located in the pocket.

Abstract: A coated tool includes a base and a coating film on the base. The coating film includes an Al2O3 layer, and a surface layer on the Al2O3 layer. The surface layer has a first erosion rate of 0.1 ?m/min or less. The first erosion rate is obtained from measurement by causing a liquid A, in which 3 mass % of amorphous Al2O3 particles having a mean particle diameter of 1.1-1.3 ?m is dispersed in purified water, to collide with the surface layer. The surface layer has a second erosion rate of 2.0 ?m/min or more. The second erosion rate is obtained from measurement by causing a liquid B, in which 3 mass % of spherical Al2O3 particles having a mean particle diameter of 2.8-3.2 ?m is dispersed in purified water, to collide with the surface layer.

Abstract: A cemented carbide may include a hard phase including W and C, and a binder phase including cubic Co. The binder phase may include Zr. The Co may include a lattice constant of more than 3.5575 ? and not more than 3.5600 ?. A coated tool may include a coating layer located on a surface of the cemented carbide. A cutting tool may include a holder that is extended from a first end toward a second end and may include a pocket on a side of the first end, and the coated tool located in the pocket.

Abstract: A cemented carbide may include a hard phase that may include W and C, a first solid solution phase and a second solid solution phase, each of which may include W, C, Ti and Zr, and a binder phase that may include an iron group metal. The cemented carbide may include 1.0-3.0 mass % of the Ti in terms of TiC, and 0.75-2.0 mass % of the Zr in terms of ZrC. An amount of the Ti in terms of TiC may be more than 1 time and less than three times an amount of the Zr in terms of ZrC. The first solid solution phase may satisfy a relationship of 0.1?Ti/(Ti+Zr)<0.4 in terms of atomic ratio. The second solid solution phase satisfies a relationship of 0.7?Ti/(Ti+Zr)?0.9 in terms of atomic ratio.

Abstract: A coated tool in the present disclosure includes a base and a coating layer located on a surface of the base. The coating layer includes an intermediate layer including Ti, and an Al2O3 layer. The Al2O3 layer is located in contact with the intermediate layer at a position further away from the base than the intermediate layer. The intermediate layer includes a plurality of first protrusions protruding toward the Al2O3 layer. An average distance between the plurality of first protrusions is 70-120 nm. A cutting tool in the present disclosure includes a holder which is extended from a first end toward a second end and includes a pocket on a side of the first end, and the coated tool located in the pocket.

Abstract: A coated tool in the present disclosure includes a base and a coating layer located on a surface of the base. The coating layer includes a TiCN layer, an intermediate layer including Ti, and an Al2O3 layer in this order from a side of the base. The Al2O3 layer is located in contact with the intermediate layer at a position further away from the base than the intermediate layer. The intermediate layer includes a plurality of first protrusions protruding toward the Al2O3 layer. An average area of the plurality of first protrusions is 1700 nm2 or less. A cutting tool in the present disclosure includes a holder which is extended from a first end toward a second end and includes a pocket on a side of the first end, and the coated tool located in the pocket.

Abstract: A coated tool in the present disclosure includes a base and a coating layer located on a surface of the base. The coating layer includes an intermediate layer including Ti, and an Al2O3 layer. The Al2O3 layer is located in contact with the intermediate layer at a position further away from the base than the intermediate layer. The intermediate layer includes a plurality of first protrusions protruding toward the Al2O3 layer. At least one of the plurality of first protrusions is a composite protrusion including second protrusions protruding in a direction intersecting with a protruding direction of the first protrusions. A percentage of the composite protrusions in the plurality of first protrusions is 30% or less. A cutting tool in the present disclosure includes a holder which is extended from a first end toward a second end and includes a pocket on a side of the first end, and the coated tool located in the pocket.

Abstract: A coated tool in the present disclosure includes a base and a coating layer located on a surface of the base. The coating layer includes an intermediate layer including Ti, and an Al2O3 layer. The Al2O3 layer is located in contact with the intermediate layer at a position further away from the base than the intermediate layer. The intermediate layer includes a plurality of first protrusions protruding toward the Al2O3 layer. At least one of the plurality of first protrusions is a composite protrusion including second protrusions protruding in a direction intersecting with a protruding direction of the first protrusions. An average number of the second protrusions in the composite protrusion is 1.4 or less. A cutting tool in the present disclosure includes a holder which is extended from a first end toward a second end and includes a pocket on a side of the first end, and the coated tool located in the pocket.

Abstract: A coated tool includes a base and a coating layer located on the base. The coating layer includes a first layer having a thickness of 1 ?m or more located near the base, and a second layer including Al2O3 particles which is in contact with the first layer and is located more away from the base than the first layer. A difference (A2?A1) between an erosion ratio A2 in the second layer and an erosion ratio A1 in the first layer is 0.60 to ?0.30 ?m/g. The erosion ratio is obtained by collision of a liquid A in which 3 mass % of spherical Al2O3 particles having a mean particle diameter of 1.1-1.3 ?m is dispersed in pure water. A cutting tool includes a holder which includes a pocket, and the coated tool located in the pocket.

Abstract: A coated tool includes a base and a coating layer located on the base. The coating layer includes a first layer having a thickness of 1 ?m or more located near the base, and a second layer located more away from the base than the first layer. An erosion ratio A2 in the second layer is 0.4 ?m/g or less which is obtained from a measurement by collision of a liquid A, in which 3 mass % of spherical Al2O3 particles having a mean particle diameter of 1.1-1.3 ?m is dispersed in pure water, against the second layer. An erosion ratio A1 in the first layer is 1.8 ?m/g or less which is obtained from a measurement by collision of the liquid A against the first layer. A cutting tool includes a holder which includes a pocket, and the coated tool located in the pocket.

Abstract: A cemented carbide may include a hard phase that may include W and C, a first solid solution phase and a second solid solution phase, each of which may include W, C, Ti and Zr, and a binder phase that may include an iron group metal. The cemented carbide may include 1.0-3.0 mass % of the Ti in terms of TiC, and 0.75-2.0 mass % of the Zr in terms of ZrC. An amount of the Ti in terms of TiC may be more than 1 time and less than three times an amount of the Zr in terms of ZrC. The first solid solution phase may satisfy a relationship of 0.1?Ti/(Ti+Zr)<0.4 in terms of atomic ratio. The second solid solution phase satisfies a relationship of 0.7?Ti/(Ti+Zr)?0.9 in terms of atomic ratio.

Abstract: A cemented carbide may include a hard phase including W and C, and a binder phase including cubic Co. The binder phase may include Zr. The Co may include a lattice constant of more than 3.5575 ? and not more than 3.5600 ?. A coated tool may include a coating layer located on a surface of the cemented carbide. A cutting tool may include a holder that is extended from a first end toward a second end and may include a pocket on a side of the first end, and the coated tool located in the pocket.