A charging member includes a conductive base material; an elastic layer that is provided on the conductive base material and has a storage elastic modulus G of 5.0 MPa or less at 100 Hz; and a surface layer that is provided on the elastic layer, in which in a Cole-Cole plot obtained by measuring the charging member in a range of 1 MHz to 0.1 Hz by an alternating current impedance method, a resistance component Ra of a capacitive semicircle including 2.5 kHz is 6.3×104Ω or less.

A charging member includes a conductive base material; an elastic layer that is provided on the conductive base material and has a storage elastic modulus G of 5.0 MPa or less at 100 Hz; and a surface layer that is provided on the elastic layer, in which in a Cole-Cole plot obtained by measuring the charging member in a range of 1 MHz to 0.1 Hz by an alternating current impedance method, a resistance component Ra of a capacitive semicircle including 2.5 kHz is 6.3×104Ω or less.

A porous polyimide film has a low dielectric loss tangent. The porous polyimide film is a reaction product of a diamine component and an acid dianhydride component. The diamine component contains an aromatic diamine represented by the following formula (1).

##STR00001##

(In formula, Y represents at least one selected from the group consisting of a single bond, —COO—, —S—, —CH(CH.sub.3)—, —C(CH.sub.3).sub.2—, —CO—, —NH—, and —NHCO—.) The porosity is 50% or more.

A porous polyimide film has a low dielectric loss tangent. The porous polyimide film is a reaction product of a diamine component and an acid dianhydride component. The diamine component contains an aromatic diamine represented by the following formula (1).

##STR00001##

(In formula, Y represents at least one selected from the group consisting of a single bond, —COO—, —S—, —CH(CH.sub.3)—, —C(CH.sub.3).sub.2—, —CO—, —NH—, and —NHCO—.) The porosity is 50% or more.

A porous polyimide film is provided to suppress an increase in a dielectric loss tangent even when immersed in water. In the porous polyimide film, a difference between a dielectric loss tangent T1 after being left to stand for 24 hours under an atmosphere of 25° C. and relative humidity of 50% and a dielectric loss tangent T2 after immersion in water for 24 hours under an atmosphere of 25° C. is 0.0030 or less.

A porous polyimide film is provided to suppress an increase in a dielectric loss tangent even when immersed in water. In the porous polyimide film, a difference between a dielectric loss tangent T1 after being left to stand for 24 hours under an atmosphere of 25° C. and relative humidity of 50% and a dielectric loss tangent T2 after immersion in water for 24 hours under an atmosphere of 25° C. is 0.0030 or less.

The present disclosure relates to a method and manufacturing method for a tire tread composition having absorption properties with high electric conductivity and excellent wear resistance. Specifically, the present disclosure relates to the fabrication of a tire composition to be used as a non-pneumatic tire, the tire composition can be used as a mobile electrode with a water supply means that can identify the location of defects in the buried conductor using the tire electrode manufacturing with improved conductivity and contact resistance with the ground even though the tire compound has wear resistance by lowering the water swelling rate compared to the previous technology.

The present disclosure relates to a method and manufacturing method for a tire tread composition having absorption properties with high electric conductivity and excellent wear resistance. Specifically, the present disclosure relates to the fabrication of a tire composition to be used as a non-pneumatic tire, the tire composition can be used as a mobile electrode with a water supply means that can identify the location of defects in the buried conductor using the tire electrode manufacturing with improved conductivity and contact resistance with the ground even though the tire compound has wear resistance by lowering the water swelling rate compared to the previous technology.

The present invention relates to a polyamide resin composition that is excellent in mechanical characteristics, bonding properties and calcium chloride resistance and is suitably bonded to an acid-modified polyolefin, wherein the polyamide resin composition includes 70 to 99 mass % of an aliphatic polyamide resin (A) having an amino group concentration of 46 to 110 μmol/g, 0 to 18 mass % of an aromatic polyamide resin (B), 0.01 to 0.50 mass % of a polyalkylene glycol alkyl ether (C), 0.01 to 0.50 mass % of a polyolefin wax (D) and 0 to 22.98 mass % of a component (E) other than (A) to (D), and the total of (A) to (E) is 100 mass %, and wherein the acid-modified polyolefin having an amount of acid modification of 8 to 100 μmol/g.

The present invention relates to a polyamide resin composition that is excellent in mechanical characteristics, bonding properties and calcium chloride resistance and is suitably bonded to an acid-modified polyolefin, wherein the polyamide resin composition includes 70 to 99 mass % of an aliphatic polyamide resin (A) having an amino group concentration of 46 to 110 μmol/g, 0 to 18 mass % of an aromatic polyamide resin (B), 0.01 to 0.50 mass % of a polyalkylene glycol alkyl ether (C), 0.01 to 0.50 mass % of a polyolefin wax (D) and 0 to 22.98 mass % of a component (E) other than (A) to (D), and the total of (A) to (E) is 100 mass %, and wherein the acid-modified polyolefin having an amount of acid modification of 8 to 100 μmol/g.