Bulky sheet material having three-dimensional protrusions
AssigneeKao Corporation
InventorsShoichi Taneichi, Manabu Kaneta, Yasuhiro Komori, Takanobu Miyamoto, Wataru Saka, Yoshihiro Sakai
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Abstract
A bulky sheet material having three-dimensional protrusions 10 is disclosed. The sheet material comprises a first layer 1 and a second layer 2 adjacent to the first layer 1. The first layer 1 and the second layer 2 is partly joined together at joints 3 in a prescribed pattern. The first layer 1 has a number of raised portions which are located among the joints 3. The second layer 2 comprises a material which exhibits elastomeric behavior. The bulky sheet material 10 exhibits elastomeric behavior as a whole and breathability.
Claims15
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/cm2, and the thickness T′ is measured under a pressure of 10 to 40 N/cm2 applied to the joint, and wherein the thickness T ranges from 1.5 to 10 mm measured under a pressure of 0.4 cN/cm2.
An absorbent article comprised of a liquid-permeable topsheet, a liquid-impermeable backsheet and an absorbent member interposed between said topsheet and said backsheet, wherein at least one of said topsheet, backsheet or absorbent member of said absorbent article is comprised of 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 crimp 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 0.4 cN/cm2, and the thickness T′ is measured under a pressure of 10 to 40 N/cm2 applied to the joint, and wherein the thickness T ranges from 1.5 to 10 mm measured under a pressure of 0.4 cN/cm2.
Dependencies are inferred from the claim text.