Patent Application

App. No. 16/018,637

Abstract

Claims (31)

1 . A breathable multilayer film comprising:

a monolithic core layer comprising a core-layer composition; wherein the core-layer composition comprises a core-layer highly breathable polymer and has a core-layer water absorption rate; and

at least a first skin layer comprising a first-skin-layer composition; wherein the first-skin-layer composition comprises a first-skin-layer highly breathable polymer and has a first-skin-layer water absorption rate;

wherein the core-layer water absorption rate is at least about 10 times larger than first-skin-layer water absorption rate.

2 . The film of claim 1 , wherein the core-layer water absorption rate is from at least about 10 to about 50 times larger than first-skin-layer water absorption rate.

3 . The film of claim 1 , wherein the breathable multilayer film comprises at least one of (i) an average density being less than about 1.0 g/cc and (ii) a contact angle from about 60 to about 70 degrees as determined according to ASTM D5946.

4 . The film of claim 1 , wherein the core-layer water absorption rate comprises at least about 15% as determined according to ISO 62.

5 . The film of claim 1 , wherein the first-skin-layer water absorption rate comprises less than about 5% as determined according to ISO 62.

6 . The film of claim 1 , further comprising a second skin layer; wherein the monolithic core layer is directly or indirectly sandwiched between the first skin layer and the second skin layer, and wherein the second skin layer comprises a second-skin-layer composition, the second-skin-layer composition comprises a second-skin-layer highly breathable polymer and has a second-skin-layer water absorption rate, in which the core-layer water absorption rate is at least about 10 times larger than second-skin-layer water absorption rate.

7 . The film of claim 6 , wherein the first-skin layer, the second-skin layer, or both are monolithic.

8 . The film of claim 6 , wherein at least one of the first-skin-layer composition, the second-skin-layer composition, or the core-layer composition is devoid of a soft polymer having a T g below 0° C.

9 . The film of claim 6 , wherein at least one of the first-skin-layer composition, the second-skin-layer composition, or the core-layer composition is devoid of a pore-forming filler.

10 . The film of claim 1 , wherein the multilayer film comprises an MVTR of at least 700 g/m 2 /day as determined by ASTM Test Method E-96D.

11 . The film of claim 1 , wherein the multilayer film has a basis weight comprising from about 5 to about 30 gsm and a thickness from about 10 microns to about 50. microns.

12 . The film of claim 6 , wherein the core layer has a core-layer thickness, the first skin layer has a first-skin-layer thickness, the second skin layer has a second-skin-layer thickness, and the core-layer thickness is greater than each of the first-skin-layer thickness and the second-skin-layer thickness.

13 . The film of claim 12 , wherein the core-layer thickness is greater than an aggregate of the first-skin-layer thickness and the second-skin-layer thickness.

14 . The film of claim 12 , wherein the multilayer film comprises no more than 50% by weight of the first skin layer, the second skin layer, or an aggregate of the first skin layer and the second skin layer.

15 . The film of claim 1 , wherein the core-layer highly breathable polymer comprises at least one of a thermoplastic polyurethane, a polyether-block-amide copolymer, a polyether-block-ester copolymer, polyester-block-amide copolymer, or a copolyester thermoplastic elastomer.

16 . The film of claim 1 , wherein the first skin layer is less hygroscopic and less tacky than the core layer.

17 . A laminate, comprising:

(a) a breathable multilayer film comprising

(i) a monolithic core layer comprising a core-layer composition; wherein the core-layer composition comprises a core-layer highly breathable polymer and has a core-layer water absorption rate; and

(ii) at least a first skin layer comprising a first-skin-layer composition;

wherein the first-skin-layer composition comprises a first-skin-layer highly breathable polymer and has a first-skin-layer water absorption rate;

wherein the core-layer water absorption rate is at least about 10 times larger than first-skin-layer water absorption rate; and

(b) at least a first fibrous layer.

18 . The laminate of claim 18 , wherein the breathable multilayer film and the first fibrous layer are laminated via a first adhesive layer positioned between the breathable multilayer film and the first fibrous layer.

19 . A process for forming a breathable multilayer film, comprising co-extruding a multilayer film, wherein the multilayer film comprises (i) a monolithic core layer comprising a core-layer composition; wherein the core-layer composition comprises a core-layer highly breathable polymer and has a core-layer water absorption rate; and (ii) at least a first skin layer comprising a first-skin-layer composition; wherein the first-skin-layer composition comprises a first-skin-layer highly breathable polymer and has a first-skin-layer water absorption rate; wherein the core-layer water absorption rate is at least about 10 times larger than first-skin-layer water absorption rate.

20 . A process for forming a laminate, comprising:

(a) providing a multilayer film comprising (i) a monolithic core layer comprising a core-layer composition; wherein the core-layer composition comprises a core-layer highly breathable polymer and has a core-layer water absorption rate; and (ii) at least a first skin layer comprising a first-skin-layer composition; wherein the first-skin-layer composition comprises a first-skin-layer highly breathable polymer and has a first-skin-layer water absorption rate; wherein the core-layer water absorption rate is at least about 10 times larger than first-skin-layer water absorption rate; and

(b) laminating the first skin layer of the multilayer film to a first fibrous layer.

Assignments (37)