Patent ID: 8308833

Claim:
A nonwoven fabric for filters in which a melt blown nonwoven fabric formed of fibers with an average fiber diameter of 1-8 μm and a spunbonded nonwoven fabric formed of core-sheath fibers with an average fiber diameter of 10 to 30 μm are laminated for integration, wherein the fibers of the melt blown nonwoven fabric and a sheath component of the core-sheath fibers of the spunbonded nonwoven fabric contain polybutylene terephthalate while a core component of the core-sheath fibers of the spunbonded nonwoven fabric contains polyethylene terephthalate, wherein the polymer composition of the sheath component of the core-sheath fibers of the spunbonded nonwoven fabric is the same as the polymer composition of the fibers of the melt blown nonwoven fabric.