Disposable diaper with breathable and liquid-resistant side flaps

A disposable diaper comprising:

• a liquid-pervious topsheet;
• a liquid-impervious backsheet;
• a liquid-absorbent core disposed disposed between the liquid-pervious topsheet and the liquid-impervious backsheet:
• and
• a pair of side flaps lying outside transversely opposite side edges of said liquid-absorbent core and extending longitudinally of the diaper,
• each of said pair of side flaps being formed from:
• a breathable and liquid-resistant first side sheet connected to a side edge portion of said liquid-previous topsheet and lying in a vicinity of a side edge of said liquid-absorbent core and extending longitudinally of the diaper;
• and
• at east one breathable and liquid-resistant second side sheet connected to at least one of side edge portions of said liquid-pervious topsheet and liquid-impervious backsheet in a vicinity of said side edge of said liquid-absorbent core, or to at least to a side edge portion of said liquid-impervious backsheet and extending longitudinally of the diaper under said first side sheets both said first and second side sheets having a water pressure resistance of 100˜1500 mm and a breathing resistance of 0.03˜0.8 Kpa·s/m.