Abstract: An absorbent article having, as a back sheet, a porous sheet obtainable by preparing, by melt blending, a melt blended solution comprising 30 to 90 parts by weight of a crystalline polyolefin and 10 to 70 parts by weight of a compound with which the crystalline polyolefin is miscible and in which the crystalline polyolefin will dissolve at or above the melting point of the crystalline polyolefin but which will phase separate below the melting point of the crystalline polyolefin, molding the blended solution into a sheet, and stretching the sheet in at least one direction. The crystalline polyolefin is a polypropylene having a weight average molecular weight (Mw) to number average molecular weight (Mn) ratio (Mw/Mn) of no more than 6.0.

Abstract: A composite sheet comprising a liquid impermeable sheet and a nonwoven fabric joined to each other by an adhesive composition, the liquid impermeable sheet having a thickness of 15 to 40 .mu.m; the nonwoven fabric having a fiber diameter of 1.5 to 3.5 deniers and a basis weight of 10 to 35 g/m.sup.2 ; and the adhesive composition comprising not less than 20% by weight of an amorphous poly-.alpha.-olefin (APAO) having a melt viscosity of 500 to 10,000 cps at 180.degree. C. and applied at an amount of 0.5 to 7 g/m.sup.2.