Abstract: An impact tool includes a brushless motor having a rotor extending in a front-rear direction and disposed in a motor housing constituted by left, right and rear motor housings. A battery pack is disposed below the motor housing in an up-down direction. A plurality of first screws extend in a left-right direction and fix the left motor housing to the right motor housing. A plurality of second screws extend in the front-rear direction and fix the rear motor housing to the left and right motor housings. A fan is disposed between the rotor and the rear motor housing, a grip housing is disposed downward of the motor housing, and a planetary gear mechanism is disposed frontward of the motor. A spindle is disposed frontward of the planetary gear mechanism, a hammer is disposed on an outer circumference of the spindle, and an anvil is disposed frontward of the hammer.

Abstract: A dielectric composition, including: dielectric grains containing a main component represented by a composition formula [(CaxSr(1-x))O]m[(TiyHfzZr(1-y-z))O2] (m is more than 1.020); a grain boundary phase located between the dielectric grains; and segregation grains each containing at least Ca, Si, and O. A first segregation grain is defined as a segregation further containing Mn among the segregation grains each containing at least Ca, Si, and O, and a second segregation grain is defined as a segregation containing substantially no Mn among the segregation grains each containing at least Ca, Si, and O. N1/(N1+N2) is more than 0.23 and 1.00 or less, in which N1 is a number density of first segregation grains in a cross-section of the dielectric composition, and N2 is a number density of second segregation grains in the cross-section of the dielectric composition.

Abstract: A water-based lubricant for plastic working of a metallic material is obtained by adding to a water-based medium: (A) a polymer and/or a salt thereof containing a carboxylic acid or a derivative thereof as a constituent monomer; (B) an oxoacid of tungsten, of silicon, or of phosphorus, or a condensate thereof, and/or a salt thereof; (C) a hydroxide of an alkali metal; and (D) a lubricating component (D), and the solid content weight ratio (A)/[(A)+(B)+(C)+(D)] is 0.05 to 0.4.

Abstract: A water-based lubricant for plastic working of a metallic material is obtained by adding to a water-based medium: (A) a polymer and/or a salt thereof containing a carboxylic acid or a derivative thereof as a constituent monomer; (B) an oxoacid of tungsten, of silicon, or of phosphorus, or a condensate thereof, and/or a salt thereof; (C) a hydroxide of an alkali metal; and (D) a lubricating component (D), and the solid content weight ratio (A)/[(A)+(B)+(C)+(D)] is 0.05 to 0.4.

Abstract: An aqueous treating solution for an Sn-based plated steel sheet, comprising (A) an organic material, (B) a water-soluble chromium compound, (C) a water-dispersible silica, and water, wherein the organic material (A) is at least one member selected from an oxy-acid with the ratio of hydroxyl group/carboxyl group in one molecule being from 3/1 to 10/1, its lactone form and an oxide derivative thereof, the water-soluble chromium compound (B) does not contain hexavalent chromium, and pH is from 0.7 to 6.0.

Abstract: An aqueous treating solution for an Sn-based plated steel sheet, comprising (A) an organic material, (B) a water-soluble chromium compound, (C) a water-dispersible silica, and water, wherein the organic material (A) is at least one member selected from an oxy-acid with the ratio of hydroxyl group/carboxyl group in one molecule being from 3/1 to 10/1, its lactone form and an oxide derivative thereof, the water-soluble chromium compound (B) does not contain hexavalent chromium, and pH is from 0.7 to 6.0.

Abstract: A rustproofing agent for a zinc plated steel sheet is provided which contains (A) a chromium aqueous solution containing an organic substance and (B) an acid metal such as a metal salt of nitric acid or phosphoric acid. All of the chromium in the chromium aqueous solution of component. A is trivalent chromium. It is preferable if the organic substance in component A contains at least one type of oxy acid or oxide thereof. The metal in the acid metal salt of component B is an alkaline earth metal, cobalt, nickel, iron, zirconium, titanium, etc. It is also preferable if (C) a water-dispersible silica is contained as an additional component. The present invention also provides a zinc plated steel sheet, in which at least one side of the surface of a zinc plated steel sheet is coated with the zinc plated steel sheet rustproofing agent and the rustproofing agent dried to form a coating with a dry coating weight of 0.01 to 3 g/m2.