Bulky nonwoven fabric with enhanced compressibility and recovery
A nonwoven fabric and a method of production of said nonwoven fabric are disclosed, wherein the nonwovens fabric comprises at least one layer, said layer comprising endless filaments, —which comprise at least a first polymeric material (A) and a second polymeric material (B) having its melting point lower than the first polymeric material A, —wherein the second polymeric material (B) extends in the longitudinal direction of the filament and forms at least a part of the surface of the filament and—the at least one layer of endless filaments comprises filament-to-filament bonds formed of the second polymeric material (B), wherein all components of the filaments are arranged across the cross-section of the filament in a non-crimpable configuration and the nonwoven fabric has a structural softness of at least 80 (m 4 mm 2 g −2 ).
1 . Nonwoven fabric comprising at least one layer, said layer comprising continuous filaments,
the continuous filaments comprising at least a first polymeric material and a second polymeric material, the second polymeric material having a melting point that is lower than that of the first polymeric material,
wherein the second polymeric material extends in a longitudinal direction of the continuous filaments and forms at least parts of the surfaces of the continuous filaments and
the at least one layer of continuous filaments comprises filament-to-filament bonds formed of the second polymeric material, wherein all components of the continuous filaments are arranged across the cross-section of the continuous filaments in a non-crimpable configuration and the nonwoven fabric has a structural softness of at least 80 (m 4 mm 2 g- 2 ), wherein
Structural
softness
=
thickness
basis
weight
×
recovery
×
compressibility
basis
weight
×
1
0
6
wherein
thickness is a thickness of the nonwoven fabric in mm,
basis weight is the basis weight of the nonwoven structure-fabric in grams per square meter,
recovery is the ratio (Tr)/(Ts), wherein (Ts) is an initial thickness of the nonwoven fabric under pre-load of 0.5 kPa and (Tr) is a recovered thickness of the nonwoven fabric measured after a 2.5 kPa load has been applied and afterwards released,
compressibility is in mm the difference between the initial thickness of the nonwoven fabric and the thickness of the nonwoven fabric under 5 N load, wherein at least 20% of fibres has the a length of the continuous filaments to a length of the nonwoven fabric ratio higher than 1.2:1.
2 . The nonwoven fabric according to claim 1 , wherein at least 10% of fibres has the length of the continous filament filaments to the length of the nonwoven fabric ratio higher than 1.5:1.
3 . The nonwoven fabric according to claim 2 , wherein at least 10% of fibres has the length of the continuous filament filaments to the length of the nonwoven fabric ratio lower than 2.5:1.
4 . The nonwoven fabric according to claim 1 , wherein the first polymeric material and/or the second polymeric material consists of or comprises as a majority component polymeric material selected from the group consisting of polyesters, polyolefins, polylactic acid, polyester copolymers, polylactide copolymers and blends thereof; and the first polymeric material is different from the second polymeric material.
5 . The nonwoven fabric according to claim 1 , wherein the continuous filaments have a core/sheath structure, wherein the first polymeric material forms the core and the second polymeric material forms the sheath.
6 . The nonwoven fabric according to claim 1 , wherein the mass ratio of the first polymeric material to the second polymeric material is 50:50 to 90:10.
7 . The nonwoven fabric according to claim 1 , wherein the nonwoven fabric has a basis weight of at least 5 gsm.
8 . The nonwoven fabric according to claim 1 , wherein the filaments have a median fibre diameter of at least 5 microns.
9 . The nonwoven fabric according to claim 1 , wherein the layer has a void volume of at least 65%.