Spunbonded laminate

Patent metadata

Field	Value
Publication number	US-11999155-B2
Application number	US-202217589386-A
Country	US
Kind code	B2
Filing date	Jan 31, 2022
Priority date	Feb 1, 2021
Publication date	Jun 4, 2024
Grant date	Jun 4, 2024

Abstract

A laminate has first and second spunbonded nonwoven layers at least one of which comprises or consists essentially of crimped continuous filaments that are bicomponent filaments having a first component based on polypropylene and a second component based on polypropylene. A specific density ρ (g/cm3) of the spunbonded nonwoven laminate depending on the surface density of the spunbonded nonwoven laminate lies below a density limit ρG defined by the following equation:ρG=9 cm−1×surface density g/cm2+0.0393 g/cm3.

First claim

We claim:

1. A laminate comprising first and second spunbonded nonwoven layers wherein at least one spunbonded nonwoven layer comprises or consists essentially of crimped continuous filaments that are bicomponent filaments of core-sheath configuration and having a first component based on polypropylene and a second component based on polypropylene, a specific density ρ in g/cm 3 of the spunbonded nonwoven laminate depending on the surface density of the spunbonded nonwoven laminate lying below a density limit ρ G defined by the following equation:
ρ G =9 cm −1 ×surface density g/cm 2 +0.0393 g/cm 3 .

2. The laminate according to claim 1 , wherein the first component consists or substantially consists of a polypropylene mixture or consists or substantially consists of a polypropylene copolymer.

3. The laminate according to claim 1 , wherein the second component consists or substantially consists of a polypropylene.

4. The laminate according to claim 1 , wherein at least one spunbonded nonwoven layer of the laminate comprises crimped continuous filaments having a titer of up to 2 denier.

5. The laminate according to claim 1 , wherein the first component is the sheath and the second component is the core.

6. The laminate according to claim 1 , wherein at least 25% of all the continuous filaments of the laminate are crimped continuous filaments having an eccentric core-sheath configuration.

7. The laminate according to claim 6 , wherein, in the crimped continuous filaments having an eccentric core-sheath configuration, the sheath of the filaments has a constant thickness D or a substantially constant cross-sectional thickness D over at least 20% of the filament circumference and a thickness of the sheath in the region of its constant or substantially constant thickness D is 0.1 to 4 μm.

8. The laminate according to claim 1 , wherein the laminate further comprises a third spunbonded nonwoven layer lying on an outer side of the laminate, at least one of the spunbonded nonwoven layers comprising crimped continuous filaments having an eccentric core-sheath configuration and including continuous filaments of a titer up to 2 denier.

9. The laminate according to claim 1 , wherein at least one of the spunbonded nonwoven layer comprises crimped continuous filaments with side-by-side configuration.

10. The laminate according to claim 1 , wherein the laminate has a surface density of 10 to 40 g/m 2 .

11. The laminate according to claim 1 , wherein the first component comprises at least one polypropylene copolymer that has a fraction of the co-monomer of 1 to 6 wt. %.

12. The laminate according to claim 1 , wherein the first and the second component have different melt-flow rates and the continuous filaments have a core-sheath configuration and the second component forms the core component and has a higher melt-flow rate than the first component forming the sheath component.

13. The laminate according to claim 1 , wherein a ratio of the melt-flow rate of the second component to the melt-flow rate of the first component is 0.9 to 2.2.

14. The laminate according to claim 1 , wherein a ratio of a polydispersity index of the first component to a polydispersity index of the second component is 0.9 to 1.4.

15. The laminate according to claim 1 , wherein a melting temperature of the first component is lower than a melting temperature of the second component and a difference between the melting temperatures is 0 to 20° C.

16. The laminate according to claim 1 , wherein the second component comprises at least 1000 ppm relative to the total filament of at least one lubricant.

Assignees

• Wagner Tobias
• Sommer Sebastian
• Bohl Patrick
• Reifenhaeuser Masch

Inventors

• Wagner Tobias
• Sommer Sebastian
• Bohl Patrick

Classifications

• B32B5/267 Primary

  characterised by at least one non-woven fabric layer that is a spunbonded fabric · CPC title

• B32B5/022 Primary

  Non-woven fabric · CPC title

• B32B37/10

  characterised by the pressing technique, e.g. using action of vacuum or fluid pressure · CPC title

• B32B2262/0253

  Polyolefin fibres · CPC title

• B32B2262/124

  Non-woven fabric · CPC title