Abstract: Provided are: a polyetherimide porous body which has a fine cell structure, a low relative permittivity and a high insulation breakdown voltage; and a method for producing the same. This polyetherimide porous body comprises a crosslinked body in which a polyetherimide having a specific repeated structural unit is ring-opened and crosslinked with a polyamine compound.

Abstract: Provided are: a polyetherimide porous body which has a low relative permittivity and is not easily cracked (or is excellent in cracking resistance) when folded, and a method for producing the porous body. This polyetherimide porous body comprises a polyetherimide crosslinked body and has a gel fraction of 10% or more, an average cell diameter of 8 ?m or less, a volume porosity of 30% or more and an insulation breakdown voltage of 30 kV/mm or more.

Abstract: An object of the present invention is to provide an electrically insulating resin sheet which is excellent in heat resistance and insulating properties and is able to maintain a predetermined shape even after applying an external force to the sheet to deform the sheet into a predetermined shape and removing the external force. An electrically insulating resin sheet having a porosity of 10 to 60%, a stress relaxation ratio of 20% or more when the sheet is extended by 5% at 23° C. and maintained for 10 minutes, and an insulation breakdown voltage of 25 kV/mm or more.

Abstract: An object of the present invention is to provide a polyimide porous body having an excellent heat resistance, a fine cell structure, and a low relative dielectric constant, and a method for producing the polyimide porous body. The present invention relates to a method for producing a polyimide porous body, comprising a step for applying a polymer solution containing a polyamide acid, a phase separation agent for separating the phases of the polyamide acid, an imidization catalyst, and a dehydrating agent, on a substrate, and drying the polymer solution to produce a phase-separated structure body having a microphase-separated structure; a step for producing a porous body by removing the phase separation agent from the phase-separated structure body; and a step for subjecting the polyamide acid in the porous body to imidization to synthesize a polyimide.

Abstract: Provided are: an electrically insulating resin sheet for motors, which is used for achieving the insulation between coil wires or between a coil wire and an iron core in a motor, and which has high heat resistance, high electrical insulation performance and a high insulation breakdown voltage; and a process for producing the electrically insulating resin sheet. The electrically insulating resin sheet for motors, which is provided with a porous resin layer comprising a thermoplastic resin, is characterized in that the resin sheet has a relative permittivity of 2.0 or less at 1 GHz. It is preferred that the porous resin layer has an average cell diameter of 5.0 ?m or less and contains cells in such an amount that the porosity is 30% or more.

Abstract: The present invention provides a gasket material to be placed between two opposing faces to provide a tight closure between them. The gasket material of the present invention, wherein an adhesive layer comprised of a cured product obtained by reacting a polyoxyalkylene polymer having at least one alkenyl group in each molecule with a compound containing two or more hydrosilyl groups on average in each molecule is formed on both surfaces of a substrate sheet, is superior in elasticity and compaction property, shows superior adhesion to various materials, does not cause cohesive failure during detachment and is superior in removability. Therefore, a superior sealing effect lasts for a long time, the gasket material can be removed without leaving residues of the adhesive layer on an adherend after removal, and workability including removal of the gasket material can be improved.