Abstract: The present invention relates to a microporous membrane, a method for producing the same, and an electrochemical cell using the same, the microporous membrane comprising pore-forming particles and a thermoplastic resin having a melting point of 50° C. to 150° C., wherein the pore-forming particles have an average particle size of 300 nm or less, and are surface-treated with at least one selected from the group consisting of a phosphonic acid containing alkyl group having 10 or more carbon atoms, a carboxylic acid containing an alicyclic hydrocarbon group having 6 to 20 carbon atoms, resin acid, a benzenesulfonic acid containing alkyl group having 10 or more carbon atoms and a salt thereof.

Abstract: A method for manufacturing a porous film includes extrusion-molding a composition including a crystalline resin capable of forming a lamella and a pore-forming particle to manufacture a precursor film, annealing the precursor film at a temperature of Tm?80° C. to Tm?3° C., and first drawing the annealed film at a temperature of about 0° C. to about 50° C. with a ratio of about 50% to about 400%, wherein the pore-forming particle is included in an amount of about 5 parts by volume to 40 parts by volume based on 100 parts by volume of the composition, and the Tm is a melting temperature of the crystalline resin. A porous film manufactured by the method, and a separator or an electro-chemical battery including the porous film are also disclosed.

Abstract: The present invention relates to a fluorine-based hollow-fiber membrane and to a production method therefor. The present invention provides: a fluorine-based hollow-fiber membrane which exhibits a sponge-like pore structure even though it has an asymmetrical structure; and a production method therefor. Consequently, the present invention can provide: a fluorine-based hollow-fiber membrane with an outstanding filtering performance and backwash performance despite also having excellent mechanical strength; and a production method therefor.