The present invention provides vinyl-based resin particles capable of forming uniform pores in a thermosetting resin film when the particles are used as a pore-forming material for a thermosetting resin. Specifically, the present invention provides vinyl-based resin particles for use in making a thermosetting resin porous, the particles having a temperature of 300 to 350 C. at 10% mass loss when heated at a rate of 10 C./min in an air atmosphere, and the particles having a mass loss percentage of 85 to 100% after being heated at 350 C. for 5 hours in an air atmosphere.

The present invention provides vinyl-based resin particles capable of forming uniform pores in a thermosetting resin film when the particles are used as a pore-forming material for a thermosetting resin. Specifically, the present invention provides vinyl-based resin particles for use in making a thermosetting resin porous, the particles having a temperature of 300 to 350 C. at 10% mass loss when heated at a rate of 10 C./min in an air atmosphere, and the particles having a mass loss percentage of 85 to 100% after being heated at 350 C. for 5 hours in an air atmosphere.

To provide a method for manufacturing a polyimide and/or a polyamide imide porous membrane with which it is possible to prepare a varnish in which microparticles are satisfactorily dispersed, even when minute microparticles are used, and to manufacture a porous membrane using the varnish. The method for manufacturing a polyimide and/or a polyamide imide porous membrane comprises a step for preparing a porous membrane manufacturing composition containing microparticles and at least one resin component selected from the group consisting of polyamic acids, polyimides, polyamide imide precursors, polyamide imides, and polyethersulfones, the preparation step including a dispersion step for causing a slurry containing the microparticles to disperse by shear and compression or shock.

To provide a method for manufacturing a polyimide and/or a polyamide imide porous membrane with which it is possible to prepare a varnish in which microparticles are satisfactorily dispersed, even when minute microparticles are used, and to manufacture a porous membrane using the varnish. The method for manufacturing a polyimide and/or a polyamide imide porous membrane comprises a step for preparing a porous membrane manufacturing composition containing microparticles and at least one resin component selected from the group consisting of polyamic acids, polyimides, polyamide imide precursors, polyamide imides, and polyethersulfones, the preparation step including a dispersion step for causing a slurry containing the microparticles to disperse by shear and compression or shock.

A method for making a polymer with a porous layer from a solid piece of polymer is disclosed. In various embodiments, the method includes heating a surface of a solid piece of polymer to a processing temperature and holding the processing temperature while displacing a porogen layer through the surface of the polymer to create a matrix layer of the solid polymer body comprising the polymer and the porogen layer. In at least one embodiment, the method also includes removing at least a portion of the layer of porogen from the matrix layer to create a porous layer of the solid piece of polymer.

A method for making a polymer with a porous layer from a solid piece of polymer is disclosed. In various embodiments, the method includes heating a surface of a solid piece of polymer to a processing temperature and holding the processing temperature while displacing a porogen layer through the surface of the polymer to create a matrix layer of the solid polymer body comprising the polymer and the porogen layer. In at least one embodiment, the method also includes removing at least a portion of the layer of porogen from the matrix layer to create a porous layer of the solid piece of polymer.

A manufacturing method of an acoustic coating in an ordered array of interconnected micro-channels intended to receive, on a reception surface, an incident acoustic wave with direction Ac normal to this surface, the method including depositing a sacrificial material on a substrate surface to form a three-dimensional scaffold of filaments, infiltrating at least one part of the three-dimensional scaffold with a thermosetting material, solidifying the thermosetting material to form a solidified material, and removing the sacrificial material from the solidified material to form the ordered array of interconnected micro-channels, the filaments forming by superimposed layers the three-dimensional scaffold being, for a given layer of filaments, oriented in a direction forming, in a plane formed by the layer, a first angle relative to the direction Ac of the incident acoustic wave, to confer acoustic properties to the ordered array of interconnected micro-channels and thus form the acoustic coating.

A porous ultra-thin polymer film has a film thickness of 10 nm-1000 nm. A method of producing the porous ultra-thin polymer film includes dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

A porous ultra-thin polymer film has a film thickness of 10 nm-1000 nm. A method of producing the porous ultra-thin polymer film includes dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

Provided are a separator capable of being used for a secondary battery such as a nonaqueous electrolyte-solution secondary battery and a secondary battery including the separator. A separator having a first layer including a porous polyethylene and an organic additive is provided. A white index of the first layer is equal to or more than 85 and equal to or less than 98, and a reduction rate of diethyl carbonate dropped on the first layer is equal to or higher than 0.048 mg/s and equal to or lower than 0.067 mg/s. The separator may further include a porous layer over the first layer.