Patent ID: 7303808

Claim:
A bulky sheet material having three-dimensional protrusions comprising a first layer and a second layer adjacent to the first layer, said first layer and said second layer being partly joined together at joints in a prescribed pattern, said first layer having a number of said protrusions which are located between said joints, said second layer comprising a material which exhibits elastomeric behavior, and said bulky sheet material exhibiting elastomeric behavior as a whole and breathability and has a recovery of 60% or more from 50% extension, and wherein said second layer comprises a web formed by carding comprising latent crimping fibers having a helical shape which are made of a thermoplastic polymer having an eccentric core-sheath or side-by-side configuration and comprising two thermoplastic polymers different in shrinkage and exhibit both thermal shrinkability and elastomeric behavior, and said first layer comprises a fiber aggregate comprising fibers which are made of a thermoplastic polymer and have substantially no thermal shrinkability or do not shrink at or below the thermal shrinkage temperature of said fibers exhibiting thermal shrinkability, said three-dimensional protrusions comprised of fiber-filled protrusions, and said sheet material having been heat-treated at or above a temperature at which thermal shrinkage of the fibers constituting the second layer is initiated, whereby said second layer shrinks to form said protrusions in said first layer, and wherein the ratio T/T′ of the thickness T of the bulky sheet material measured at the protrusions to the thickness T′ of the bulky sheet material measured at the joints is at least 2, wherein the thickness T is measured under a pressure of 0.4cN/cm 2 , and the thickness T′ is measured under a pressure of 10 to 40 N/cm 2 applied to the joint, and wherein the thickness T ranges from 1.5 to 10 mm measured under a pressure of 0.4 cN/cm 2 .