A hydroentangled fibrous structure. The hydroentangled fibrous structure can be incorporated into an absorbent article. Methods of forming a hydroentangled fibrous structure are also provided.

A hydroentangled fibrous structure. The hydroentangled fibrous structure can be incorporated into an absorbent article. Methods of forming a hydroentangled fibrous structure are also provided.

A fiber structure includes crimped staple fibers and heat-bonding conjugate staple fibers mixed in a specific weight ratio, the heat-bonding conjugate staple fibers having, as a heat-bonding component disposed on the surface thereof, a thermoplastic resin having a melting point lower by 40 C. or more than that of a thermoplastic resin constituting the crimped staple fibers, the fiber structure having scattered fixing points in which the heat-bonding conjugate staple fibers are heat-fused and intersect together and/or scattered fixing points in which the heat-bonding conjugate staple fibers and the crimped staple fibers are heat-fused and intersect together, the fiber structure having a specified thickness and density and having a laminated structure of three or more layers, wherein the hardness ratio between an intermediate layer portion and a surface layer portion defined when the fiber structure is equally divided into three portions is 0.60 or more.

A fiber structure includes crimped staple fibers and heat-bonding conjugate staple fibers mixed in a specific weight ratio, the heat-bonding conjugate staple fibers having, as a heat-bonding component disposed on the surface thereof, a thermoplastic resin having a melting point lower by 40 C. or more than that of a thermoplastic resin constituting the crimped staple fibers, the fiber structure having scattered fixing points in which the heat-bonding conjugate staple fibers are heat-fused and intersect together and/or scattered fixing points in which the heat-bonding conjugate staple fibers and the crimped staple fibers are heat-fused and intersect together, the fiber structure having a specified thickness and density and having a laminated structure of three or more layers, wherein the hardness ratio between an intermediate layer portion and a surface layer portion defined when the fiber structure is equally divided into three portions is 0.60 or more.

A nonwoven biofabric comprises a web comprising (a) biodegradable polymeric melt blown fibers, and (b) a plurality of particles enmeshed in the biodegradable polymeric meltblown fibers.

A nonwoven biofabric comprises a web comprising (a) biodegradable polymeric melt blown fibers, and (b) a plurality of particles enmeshed in the biodegradable polymeric meltblown fibers.

A masterbatch is disclosed, along with associated methods, and biodegradable filaments, fibers, yarns and fabrics. The masterbatch includes 0.2 to 5 mass % CaCO.sub.3, an aliphatic polyester with a repeat unit having from two to six carbons in the chain between ester groups, with the proviso that the 2 to 6 carbons in the chain do not include side chain carbons, and a carrier polymer selected from the group consisting of PET, nylon, other thermoplastic polymers, and combinations thereof.

A masterbatch is disclosed, along with associated methods, and biodegradable filaments, fibers, yarns and fabrics. The masterbatch includes 0.2 to 5 mass % CaCO.sub.3, an aliphatic polyester with a repeat unit having from two to six carbons in the chain between ester groups, with the proviso that the 2 to 6 carbons in the chain do not include side chain carbons, and a carrier polymer selected from the group consisting of PET, nylon, other thermoplastic polymers, and combinations thereof.

A fiber sheet is densely charged with electric charge and provides an electret fiber sheet that has excellent dust collecting performance. The electret fiber sheet is an electret fiber sheet in which averages of a* values and b* values satisfy all requirements of the following (a) to (c): (a) 10average of (a* values)40; (b) 25average of (b* values)0; and (c) 5average of [(a* values)+(b* values)]40; wherein a* and b* are values measured by a spectrophotometer when a red positive charge toner and a blue negative charge toner are attached.

A fiber sheet is densely charged with electric charge and provides an electret fiber sheet that has excellent dust collecting performance. The electret fiber sheet is an electret fiber sheet in which averages of a* values and b* values satisfy all requirements of the following (a) to (c): (a) 10average of (a* values)40; (b) 25average of (b* values)0; and (c) 5average of [(a* values)+(b* values)]40; wherein a* and b* are values measured by a spectrophotometer when a red positive charge toner and a blue negative charge toner are attached.