Breathable nonwoven composite

Patent metadata

Field	Value
Publication number	US-10087575-B2
Application number	US-201113699327-A
Country	US
Kind code	B2
Filing date	May 23, 2011
Priority date	May 25, 2010
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

Coated nonwoven fabric comprising a nonwoven fabric layer and a coating, said coating comprises a polymer having a branching index g′ of equal or below 0.9.

First claim

The invention claimed is:

1. Composite comprising:
(a) a nonwoven fabric (NF) being the substrate of the composite, said nonwoven fabric (NF) comprises a polymer (P-1) selected from the group consisting of polyethylene (PE-1), polypropylene (PP-1), polyethylene terephthalate (PET) and polyamide (PA), and
(b) a coating layer (CL) overlaying at least one surface of the nonwoven fabric (NF), said coating layer (CL) comprises a polymer (P-2) being a polypropylene (PP-2), wherein the coating layer (CL) and/or the polymer (P-2) has (have):
(i) a branching index g′ of equal or below 0.9, and optionally
(ii) a strain hardening factor (SHF) of at least 2.0 measured at a strain rate of 3.0 s-1 and a Hencky strain of 2.5,

wherein the coating layer (CL) has an average thickness of 2.0 to 25 μm and is free of pores, and the polymer (P-2) is the only polymer within the coating layer (CL).

2. Composite according to claim 1 , wherein the coating layer (CL) and/or the polymer (P-2) has (have), (a) a strain hardening factor (SHF) of at least 1.5 measured at a strain rate of 1.0 s-1 and a Hencky strain of 2.0, and/or (b) a LAOS non-linearity factor (LAOS-NLF) measured according to the LAOS method of at least 2.5, and/or (c) a F30 melt strength of at least 3.0 cN at 200° C. determined by the Rheotens test.

3. Composite according to claim 1 , wherein the polymer (P-2) is (a) a polypropylene (PP-2) having a melt flow rate MFR2 (230° C.) measured according to ISO 1133 of at least 15.0 g/10 min.

4. Composite according to claim 1 , wherein the coating layer (CL) (a) is non-stretched, and/or (b) has a weight per unit area of equal or below 20 g/m2.

5. Composite according to claim 1 , wherein the nonwoven fabric (NF) has a weight per unit area at least 15 g/m2.

6. Composite according to claim 1 , wherein the nonwoven fabric (NF) is a melt blown web.

7. Composite according to claim 1 , wherein the nonwoven fabric (NF) is a spunbonded fabric.

8. Composite according to claim 1 , wherein the polypropylene (PP-1) is a propylene homopolymer (H-PP-1).

9. Composite according to claim 1 , wherein no adhesive (A) between the coating layer (CL) and the nonwoven fabric (NF) is present.

10. Composite according to claim 1 , wherein the coating layer (CL) is an extrusion coating layer.

11. Process for the preparation of a composite as defined in claim 1 comprising the steps of:
(a) extruding the polymer (P-2) and
(b) coating the nonwoven fabric (NF) comprising the polymer (P-1) with the extruded polymer (P-2).

Assignees

• Tynys Antti
• Gilles Philippe
• Fiebig Joachim
• Van Paridon Henk
• Broeders Bert
• Sars Wilhelmus Henricus Adolf
• Ackermans Nina
• Borealis Ag

Inventors

• Tynys Antti
• Gilles Philippe
• Fiebig Joachim
• Van Paridon Henk
• Broeders Bert
• Sars Wilhelmus Henricus Adolf
• Ackermans Nina

Classifications

• D06N3/0034

  Polyamide fibres (for elastomeric fibres D06N3/0025) · CPC title

• D06N2209/123

  Breathable · CPC title

• D06N3/045 Primary

  with polyolefin or polystyrene (co-)polymers · CPC title

• D06N3/0036

  Polyester fibres (for elastomeric fibres D06N3/0025) · CPC title

• D06N3/0011

  using non-woven fabrics · CPC title