Method of making a spunbond laminate

Patent metadata

Field	Value
Publication number	US-11833802-B2
Application number	US-202217694931-A
Country	US
Kind code	B2
Filing date	Mar 15, 2022
Priority date	Jul 30, 2019
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

A spunbond nonwoven laminate has a first spunbond nonwoven layer having crimped filaments formed by a first component on an outer surface of the filaments of the first layer consisting or substantially consisting of a polyolefin and a second component consisting or substantially consisting of a plastic having a higher melting point than the polyolefin of the first component of the filaments of the first layer. A second outermost spunbond nonwoven layer on the first layer having filaments as a cover layer and formed by a first component on an outer surface of the filaments of the second layer consisting or substantially consisting of a polyolefin, and a second component consisting or substantially consisting of a plastic having a higher melting point than the polyolefin of the first component of the filaments of the second layer.

First claim

The invention claimed is:

1. A method of making a spunbond nonwoven laminate, the method comprising the steps of:
providing a first spunbond nonwoven layer having crimped multicomponent or bicomponent filaments and formed by
a first component on an outer surface of the filaments of the first layer consisting or substantially consisting of a polyolefin, and
a second component consisting or substantially consisting of a plastic having a higher melting point than the polyolefin of the first component of the filaments of the first layer

preconsolidating the first layer with hot air and imparting to the filaments of the first layer a predetermined crimp;
providing a second outermost spunbond nonwoven layer having multicomponent or bicomponent filaments as a cover layer and formed by
a first component on an outer surface of the filaments of the second layer consisting or substantially consisting of a polyolefin, and
a second component consisting or substantially consisting of a plastic having a higher melting point than the polyolefin of the first component of the filaments of the second layer, a polyolefin portion of the first component of the filaments of the second layer being greater than a polyolefin portion of the first component of the filaments of the first layer;

preconsolidating the second layer with hot air and imparting to the filaments of the second layer a degree of crimp equal to or less than the predetermined degree of crimp of the filaments of the first layer; and
finally consolidating the spunbond nonwoven laminate formed by the first and second layers with hot air.

2. The method according to claim 1 , wherein first the cover layer is preconsolidated, and then the first spunbond nonwoven layer is formed on the second spunbond nonwoven layer and is in turn preconsolidated.

3. The method according to claim 1 , further comprising the step of using multicomponent or bicomponent filaments for the second spunbond nonwoven layer.

4. The method according to claim 1 , further comprising the step of:
imparting to the filaments of the second outermost layer a titer that is less than a titer of the filaments of the first layer.

5. The method according to claim 1 , wherein the second component of the filaments of the first layer consists or substantially consists of polypropylene or polyester.

6. The method according to claim 1 , wherein the polyolefin portion of the filaments of the first layer is less than 40% by weight.

7. The method according to claim 1 , further comprising the step of:
imparting to the filaments of the first layer a titer of more than 1.5 den.

8. The method according to claim 1 , wherein the polyolefin of the first component of the filaments of the first layer is polyethylene having a melt flow rate of less than 35 g/10 min.

9. The method according to claim 1 , wherein the second component of the filaments of the first layer consists or substantially consists of polypropylene having a melt flow rate of more than 25 g/10 min.

10. The method according to claim 1 , wherein the second component of the filaments of the second layer consists or substantially consists of polypropylene.

11. The method according to claim 1 , wherein the polyolefin portion of the filaments of the second layer is more than 33% by weight, and the polyolefin portion is 40% by weight to 65% by weight.

12. The method according to claim 1 , wherein the multicomponent or bicomponent filaments of the second layer have an eccentric core-sheath configuration or a side-by-side configuration.

13. The method according to claim 1 , wherein the first component on the outer surface of the filaments of the second layer consists or substantially consists of polyethylene having a melt-flow rate greater than 15 g/10 min.

14. The method according to claim 13 , wherein the melt flow rate of the polypropylene of the second component of the second layer is more than 25 g/10 min.

15. The method according to claim 1 , further comprising the step of:
imparting to the second layer a weight per unit area of less than a weight per unit area of the first layer.

16. The method according to claim 1 , wherein a strength of the spunbond nonwoven laminate in the machine direction is greater than 25 N/5 cm, the spunbond nonwoven laminate in particular having a basis weight of 12 to 50 g/m 2 .

17. The method according to claim 1 , wherein a thickness of the spunbond nonwoven laminate is more than 0.50 mm, and the spunbond nonwoven laminate has in particular a basis weight from 12 to 50 g/m 2 .

18. The method according to claim 1 , wherein a difference between a titer of the filaments of the first layer and a titer of the filaments of the second layer is at least 0.2 den.

Assignees

• Wagner Tobias
• Sommer Sebastian
• Bohl Patrick
• Roesner Andreas
• Geus Hans Georg
• Linke Gerold
• Reifenhaeuser Masch

Inventors

• Wagner Tobias
• Sommer Sebastian
• Bohl Patrick
• Roesner Andreas
• Geus Hans-Georg
• Linke Gerold

Classifications

• B32B5/26 Primary

  another layer {next to it} also being fibrous or filamentary {(relative arrangement of fibres or filaments of different layers B32B5/12)} · CPC title

• B32B5/022

  Non-woven fabric · CPC title

• B32B37/144

  using layers with different mechanical or chemical conditions or properties, e.g. layers with different thermal shrinkage, layers under tension during bonding (constructional features for tensioning B32B38/1825) · CPC title

• B32B38/0036

  Heat treatment (for heating or cooling of layers during lamination B32B37/06, B32B37/08) · CPC title

• D04H3/007 Primary

  Addition polymers · CPC title