A nonwoven web is made by displacing an air-permeable mesh-belt conveyor in a horizontal travel direction and spinning and then depositing crimped continuous filaments as a web at a deposit region on the air-permeable mesh-belt conveyor. A first preconsolidation stage is provided downstream of the deposit region and a second preconsolidation separated by a suction gap from the first stage. Air is drawn air through the web and the conveyor at the deposit region at a first predetermined speed, the first and second consolidation stages at a second and third predetermined speeds, and at the suction gap either not at all or at a fourth predetermined equal to at most substantially less than the second predetermined speed.

A method of creating a soft and lofty continuous fiber nonwoven web is provided. The method includes providing first and second, different molten polymers to a spinneret defining a plurality of orifices and flowing a fluid intermediate the spinneret and a moving porous member. The method includes using the fluid to draw the first and second molten polymers, in a direction toward the porous member, through at least some of the plurality of orifices to form a plurality of individual continuous fiber strands. The method includes depositing the continuous fiber strands onto the porous member at a first location to produce an intermediate continuous fiber nonwoven web, and intermittently varying, in at least two different zones, a vacuum force applied to the moving porous member and to the intermediate web downstream of the first location and without the addition of more continuous fibers and without any heat applied.

A method of creating a soft and lofty continuous fiber nonwoven web is provided. The method includes providing a first molten polymer and a second, different molten polymer to a spinneret defining a plurality of orifices and flowing a fluid intermediate the spinneret and a moving porous member. The method includes using the fluid to draw the first and second molten polymer components, in a direction toward the moving porous member, through at least some of the plurality of orifices to form a plurality of individual continuous fiber strands. The method includes depositing the continuous fiber strands onto the moving porous member at a first location to produce an intermediate continuous fiber nonwoven web, and intermittently varying a vacuum force applied to the moving porous member and to the intermediate web downstream of the first location and without the addition of more continuous fibers and without any heat applied.

The invention relates to a method for making a spunbonded high loft nonwoven web comprising crimped multicomponent fibers, the process comprising continuously spinning the fibers, directing the fibers to a spin-belt by deflectors and/or air streams, laying down the fibers on the spinbelt and pre-consolidating the fibers after laydown using one or more pre-consolidation rollers to form a pre-consolidated web, wherein a first component of the fibers comprises a PP homopolymer and a second component of the fibers comprises a PP/PE copolymer, wherein the pre-consolidation rollers are operated at a temperature of smaller 110 C. and/or a linear contact force of smaller 5 N/mm.

A nonwoven web is made by displacing an air-permeable mesh-belt conveyor in a horizontal travel direction and spinning and then depositing crimped continuous filaments as a web at a deposit region on the air-permeable mesh-belt conveyor. A first preconsolidation stage is provided downstream of the deposit region and a second preconsolidation separated by a suction gap from the first stage. Air is drawn air through the web and the conveyor at the deposit region at a first predetermined speed, the first and second consolidation stages at a second and third predetermined speeds, and at the suction gap either not at all or at a fourth predetermined equal to at most substantially less than the second predetermined speed.

A polyimide fiber assembly of the present invention includes polyimide fibers having curved shapes with an average fiber diameter falling within a range of greater than 1 m to not greater than 100 m, the polyimide fiber assembly having a bulk density falling within a range of not less than 1 kg/m.sup.3 to not greater than 30 kg/m.sup.3. This makes it possible to realize a polyimide fiber assembly that is both excellent in thermal insulation performance and sound absorbency and light in weight. The polyimide fiber assembly of the present invention can be obtained by a production method comprising the steps of: (i) discharging a polymeric resin solution obtained by dissolving polyamic acid or polyimide in an organic solvent; and (ii) using external force to cause the polymeric resin solution thus discharged to fly in a direction of the external force, the external force being external force of gas from a direction intersecting with a discharge direction in which the polymeric resin solution is discharged, and then forming a polymeric resin into fibers by spinning while vaporizing the organic solvent contained in the polymeric resin solution.

A polyimide fiber assembly of the present invention includes polyimide fibers having curved shapes with an average fiber diameter falling within a range of greater than 1 m to not greater than 100 m, the polyimide fiber assembly having a bulk density falling within a range of not less than 1 kg/m.sup.3 to not greater than 30 kg/m.sup.3. This makes it possible to realize a polyimide fiber assembly that is both excellent in thermal insulation performance and sound absorbency and light in weight. The polyimide fiber assembly of the present invention can be obtained by a production method comprising the steps of: (i) discharging a polymeric resin solution obtained by dissolving polyamic acid or polyimide in an organic solvent; and (ii) using external force to cause the polymeric resin solution thus discharged to fly in a direction of the external force, the external force being external force of gas from a direction intersecting with a discharge direction in which the polymeric resin solution is discharged, and then forming a polymeric resin into fibers by spinning while vaporizing the organic solvent contained in the polymeric resin solution.

A method of creating a soft and lofty continuous fiber nonwoven web is provided. The method includes providing first and second, different molten polymers to a spinneret defining a plurality of orifices and flowing a fluid intermediate the spinneret and a moving porous member. The method includes using the fluid to draw the first and second molten polymers, in a direction toward the porous member, through at least some of the plurality of orifices to form a plurality of individual continuous fiber strands. The method includes depositing the continuous fiber strands onto the porous member at a first location to produce an intermediate continuous fiber nonwoven web, and varying, in at least two different zones, a vacuum force applied to the moving porous member and to the intermediate web downstream of the first location and without any heat applied.