Abstract: Provided is a piezoelectric film which is capable of suppressing a decrease in acoustic characteristics associated with use of a long period of time and has high durability. The piezoelectric film includes a piezoelectric layer consisting of a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material and electrode layers formed on both surfaces of the piezoelectric layer, in which, in a case where a smaller value of a domain ratio X between a c domain and an a domain, which is measured by an X-ray diffraction method from one main surface side of the piezoelectric layer, or a domain ratio Y between a c domain and an a domain, which is measured by an X-ray diffraction method from the other main surface side of the piezoelectric layer, is set to 1.00, the other domain ratio is 1.05 or more.

Abstract: Provided is a piezoelectric film capable of realizing an electroacoustic conversion film or the like in which the durability is high and a sufficient sound pressure with respect to an input operating voltage is obtained. The piezoelectric film is a piezoelectric film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, and electrode layers which are provided on both surfaces of the polymer-based piezoelectric composite material, in which in a case where a cross section of the piezoelectric film in a thickness direction is observed with a scanning electron microscope, the polymer-based piezoelectric composite material is divided into two equal regions in the thickness direction, and void volumes of the two regions are measured, a ratio of the void volume obtained by dividing the void volume of the region with a larger void volume by the void volume of the region with a smaller void volume is 1.2 or greater.

Abstract: An object of the present invention is to provide a piezoelectric film that has satisfactory durability, is capable of outputting a sound with a high sound pressure, decreases the resistance of an electrode layer, and is capable of suppressing heat generation. The above-described object is achieved by providing the piezoelectric film including a piezoelectric layer containing piezoelectric particles in a matrix that contains a polymer material, electrode layers provided on both surfaces of the piezoelectric layer, and an interlayer provided on at least one side between the piezoelectric layer and the electrode layers, in which the interlayer contains carbon and/or a metal, and a metal atom concentration of 30 to 90 atm % or a carbon atom concentration of 85 to 95 atm % is satisfied.

Abstract: An object of the present invention is to provide a piezoelectric film capable of realizing an electroacoustic conversion film or the like in which the durability is high and a sufficient sound pressure with respect to an input operating voltage is obtained.

Abstract: Provided is a piezoelectric film capable of realizing an electroacoustic conversion film or the like in which the durability is high and a sufficient sound pressure with respect to an input operating voltage is obtained. The piezoelectric film is a piezoelectric film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, and electrode layers which are provided on both surfaces of the polymer-based piezoelectric composite material, in which in a case where a cross section of the piezoelectric film in a thickness direction is observed with a scanning electron microscope, the polymer-based piezoelectric composite material is divided into two equal regions in the thickness direction, and void volumes of the two regions are measured, a ratio of the void volume obtained by dividing the void volume of the region with a larger void volume by the void volume of the region with a smaller void volume is 1.2 or greater.

Abstract: An aspect of the present invention relates to a magnetic recording medium, which comprises a nonmagnetic layer comprising nonmagnetic powder and binder on a nonmagnetic support, and a magnetic layer comprising ferromagnetic powder and binder on the nonmagnetic layer, wherein the magnetic layer further comprises carbon black, and a state in which the carbon black is present, as observed in a reflection electron image of a surface of the magnetic layer obtained by a scanning electron microscope, satisfies condition 1 and condition 2 below: condition 1: a number of carbon black particles with a particle size of greater than or equal to 140 nm is greater than or equal to 30 per 1,000 ?m2 of area; and condition 2: a number of carbon black particles with a particle size of greater than or equal to 220 nm is less than or equal to 10 per 1,000 ?m2 of area.

Abstract: A polymerizable composition contains (A) a polymerization initiator that is an acetophenone-based compound or an acylphosphine oxide-based compound, (B) a polymerizable compound, (C) at least either a tungsten compound or a metal boride, and (D) an alkali-soluble binder.

Abstract: The method of manufacturing hexagonal ferrite magnetic particles comprises applying, in a water-based solution, an adhering matter comprising a glass component and an alkaline earth metal to iron oxide particles to which a surfactant adheres, and calcining the iron oxide particles to which the adhering matter adheres to obtain a calcined product in which a main component that is detected by X-ray diffraction analysis is hexagonal ferrite.

Abstract: An aspect of the present invention relates to a magnetic recording medium, which comprises a nonmagnetic layer comprising nonmagnetic powder and binder on a nonmagnetic support, and a magnetic layer comprising ferromagnetic powder and binder on the nonmagnetic layer, wherein the magnetic layer further comprises carbon black, and a state in which the carbon black is present, as observed in a reflection electron image of a surface of the magnetic layer obtained by a scanning electron microscope, satisfies condition 1 and condition 2 below: condition 1: a number of carbon black particles with a particle size of greater than or equal to 140 nm is greater than or equal to 30 per 1,000 ?m2 of area; and condition 2: a number of carbon black particles with a particle size of greater than or equal to 220 nm is less than or equal to 10 per 1,000 ?m2 of area.

Abstract: The method of manufacturing hexagonal ferrite magnetic particles comprises applying an adhering matter comprising a glass component and an alkaline earth metal to hexagonal ferrite magnetic particles, and subjecting the hexagonal ferrite magnetic particles to which the adhering matter has been applied to a heat treatment.

Abstract: The method of manufacturing hexagonal ferrite magnetic particles comprises applying, in a water-based solution, an adhering matter comprising a glass component and an alkaline earth metal to iron oxide particles to which a surfactant adheres, and calcining the iron oxide particles to which the adhering matter adheres to obtain a calcined product in which a main component that is detected by X-ray diffraction analysis is hexagonal ferrite.

Abstract: A polymerizable composition contains (A) a polymerization initiator that is an acetophenone-based compound or an acylphosphine oxide-based compound, (B) a polymerizable compound, (C) at least either a tungsten compound or a metal boride, and (D) an alkali-soluble binder.

Abstract: A polymerizable composition contains (A) a polymerization initiator that is an acetophenone-based compound or an acylphosphine oxide-based compound, (B) a polymerizable compound, (C) at least either a tungsten compound or a metal boride, and (D) an alkali-soluble binder.

Abstract: A polymerizable composition contains (A) a polymerization initiator that is an acetophenone-based compound or an acylphosphine oxide-based compound, (B) a polymerizable compound, (C) at least either a tungsten compound or a metal boride, and (D) an alkali-soluble binder.

Abstract: A method of vulcanizing an object formed of unvulcanized rubber, in which the unvulcanized-rubber formed object is vulcanized by pressing and heating by mold means, comprises disposing a fiber sheet member on a surface of the unvulcanized-rubber formed object and vulcanizing the unvulcanized-rubber formed object by the mold means.

Abstract: A method of vulcanizing an object formed of unvulcanized rubber, in which the unvulcanized-rubber formed object is vulcanized by pressing and heating by mold means, comprises disposing a fiber sheet member on a surface of the unvulcanized-rubber formed object and vulcanizing the unvulcanized-rubber formed object by the mold means.

Abstract: A method of vulcanizing an object formed of unvulcanized rubber, in which the unvulcanized-rubber formed object is vulcanized by pressing and heating by mold means, comprises disposing a fiber sheet member on a surface of the unvulcanized-rubber formed object and vulcanizing the unvulcanized-rubber formed object by the mold means.