Nonwoven material and a method for producing nonwoven material

Patent metadata

Field	Value
Publication number	US-9850604-B2
Application number	US-201514618766-A
Country	US
Kind code	B2
Filing date	Feb 10, 2015
Priority date	Dec 7, 2005
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

The present invention relates to a nonwoven material for use as an absorbent wiping material produced by hydroentangling of a substrate web comprising at least one layer of fibers selected from amongst synthetic fibers, regenerated fibers and natural fibers, wherein the nonwoven material ( 1 ) has a base level h 0 with protuberances ( 2, 3 ) on one side, wherein the protuberances ( 2, 3 ) form at least a first and a second surface structure respectively in the form of first ( 2 ) and second ( 3 ) protuberances from the base level h 0 , wherein the first protuberances ( 2 ) have a height h 1 from the base level h 0 and the second protuberances ( 3 ) have a height h 2 from the base level h 0 , where h 2 is higher than h 1 , and each of the second protuberances ( 3 ) occupies an area of the surface of the base level at least 4 times greater than each of the first protuberances ( 2 ). The present invention also relates to a method for producing a nonwoven material ( 111 ), wherein hydroentangling of a substrate web ( 101 ), which comprises natural fibers having a length of less than 10 mm, takes place on a surface-shaped carrier device ( 109 ) containing holes which form at least a first and a second pattern in the form of first and second holes respectively, wherein the second holes are at least 4 times larger than the first holes.

First claim

The invention claimed is:

1. A method for producing a nonwoven material, comprising the following steps:
a) providing a substrate web comprising natural fibres having a length of less than 10 mm;
b) providing a surface-shaped carrier device comprising holes which form at least a first and a second pattern in the form of first and second holes respectively, wherein the second holes are larger than the first holes;
c) transferring the substrate web to the surface-shaped carrier device; and
d) hydroentangling the substrate web on the carrier device with jets of liquid under high pressure, so that the fibres of the substrate web penetrate down into the holes to form first protuberances in the first holes and second protuberances in the second holes, wherein the second protuberances have a height that is higher than a height of the first protuberances on a first side of the nonwoven material.

2. The method as claimed in claim 1 , wherein the second holes are at least 8 times larger than the first holes.

3. The method as claimed in claim 1 , wherein the carrier device has additional holes which are larger than the holes in the second patterns.

4. The method as claimed in claim 1 , wherein the carrier device has additional holes which are smaller than the holes in the first patterns.

5. The method as claimed in claim 1 , wherein the natural fibres of the substrate web provided in step a) comprises pulp fibres.

6. The method as claimed in claim 1 , wherein the second holes are at least 4 times larger than the first holes.

7. The method as claimed in claim 1 , wherein the substrate web and carrier device provided in steps a) and b) are configured such that, after performing steps c) and d):
the nonwoven material has a base level h 0 with the first protuberances and the second protuberances on one side, the first protuberances exhibit a height h 1 from the base level h 0 , the second protuberances exhibit a height h 2 from the base level h 0 , and there is a difference of at least 100 μm between h 1 and h 2 ,
each of the second protuberances occupies an area of the surface of the base level at least 4 times greater than each of the first protuberances, and
the fibres include pulp fibres that are present in a higher proportion in the protuberances than in the rest of the nonwoven material.

8. The method as claimed in claim 1 , wherein the carrier device provided in step b) is configured such that, after performing steps c) and d), the second side of the nonwoven material is essentially smooth.

9. The method as claimed in claim 1 , wherein the substrate web and carrier device provided in steps a) and b) are configured such that, after performing steps c) and d), each of the second protuberances occupies an area of the surface of the base level at least 8 times greater than each of the first protuberances.

10. The method as claimed in claim 1 , wherein the substrate web and carrier device provided in steps a) and b) are configured such that, after performing steps c) and d):
the nonwoven material has a base level h 0 with the first protuberances and the second protuberances on one side, the first protuberances exhibit a height h 1 from the base level h 0 , the second protuberances exhibit a height h 2 from the base level h 0 , the height h 1 being at least 200 μm, and the height h 2 being at least 300 μm.

11. The method as claimed in claim 7 , wherein the difference between h 1 and h 2 is at least 200 μm.

12. The method as claimed in claim 7 , wherein the substrate web and carrier device provided in steps a) and b) are configured such that, after performing steps c) and d), the nonwoven material has additional protuberances with at least an additional height h 2 1 from the base level h 0 , wherein the height h 2 1 of the additional protuberance is higher than h 2 and occupies a larger area of the surface of the base level than the second protuberances.

13. The method as claimed in claim 7 , wherein the substrate web and carrier device provided in steps a) and b) are configured such that, after performing steps c) and d), the nonwoven material has additional protuberances having at least an additional height h 1 1 from the base level h 0 , wherein the height h 1 1 of the additional protuberance is lower than h 1 and occupies a smaller area of the surface of the base level than the first protuberances.

14. The method as claimed in claim 1 , wherein the substrate web and carrier device provided in steps a) and b) are configured such that, after performing steps c) and d):
the nonwoven material has a base level h 0 with the first protuberances and the second protuberances on one side, the first protuberances exhibit a height h 1 from the base level h 0 , the second protuberances exhibit a height h 2 from the base level h 0 , h 2 being at least 1.5 times higher than h 1 .

15. The method as claimed in claim 1 , wherein the substrate web provided in step a) further comprises pulp fibres have a length of less than 10 mm.

16. The method as claimed in claim 7 , wherein the substrate web provided in step a) consists essentially of continuous filaments, pulp fibres having a length of less than 10 mm, and staple fibres, and wherein the proportion of pulp fibres having a length of less than 10 mm is at least 5% by weight of the substrate web of fibres.

Assignees

• Sca Hygiene Prod Ab

Inventors

• Strandqvist Mikael
• Ahoniemi Hannu
• Burman Daniel

Classifications

• D04H1/498

  entanglement of layered webs · CPC title

• D04H5/03

  by fluid jet · CPC title

• D04H3/11

  by fluid jet · CPC title

• A61F2013/15983

  by hydroentangled technique · CPC title

• Y10T442/608

  Including strand or fiber material which is of specific structural definition · CPC title