Structured film containing beta-nucleating agent and method of making the same

Patent metadata

Field	Value
Publication number	US-10076450-B2
Application number	US-201615173814-A
Country	US
Kind code	B2
Filing date	Jun 6, 2016
Priority date	Dec 13, 2011
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

A structured film of a semi-crystalline polyolefin and a beta-nucleating agent is disclosed. The structured film has a backing and upstanding posts attached to the backing. At least a portion of the film typically includes beta-spherulites. In some embodiments, the backing is microporous while the upstanding posts have lower porosity. A method of making a structured film is also disclosed. The method includes extruding a melt of a polyolefin and a beta-nucleating agent in the presence of a tool to provide the structured film having upstanding posts on a backing and cooling at least a portion of the structured film to a temperature sufficient to form beta-spherulites. In some embodiments, the method further includes stretching the structured film containing beta-spherulites to provide micropores in the backing.

First claim

What is claimed is:

1. A laminate comprising:
a structured film comprising a backing having opposing first and second surfaces and upstanding posts with base portions attached to the first surface of the backing and free ends distal from the backing; and
a carrier joined to the second surface of the backing, wherein the structured film comprises a semi-crystalline polyolefin and at least one of a beta-nucleating agent or beta-spherulites of the semi-crystalline polyolefin in at least the upstanding posts, wherein the backing is microporous, and wherein the upstanding posts have lower porosity than the backing.

2. The laminate of claim 1 , wherein the carrier comprises at least one of a fibrous material or a plastic film.

3. The laminate of claim 2 , wherein the carrier comprises a nonwoven material.

4. The laminate of claim 1 , wherein carrier is joined to the second surface of the backing with adhesive.

5. The laminate of claim 1 , wherein the carrier is joined to the second surface of the backing by ultrasonic bonding.

6. The laminate of claim 1 , wherein the laminate is included in an absorbent article.

7. The laminate of claim 1 , wherein the backing has a greater opacity than the upstanding posts.

8. The laminate of claim 1 , wherein the semi-crystalline polyolefin is substantially free of cavitating agents and substantially free of diluents that phase separate below a melting temperature of the semi-crystalline polyolefin.

9. The laminate of claim 1 , wherein the semi-crystalline polyolefin comprises polypropylene.

10. The laminate of claim 1 , wherein the semi-crystalline polyolefin comprises at least one of propylene homopolymer, a copolymer of propylene and other olefins, or a blend of a polypropylene homopolymer and a different polyolefin.

11. The laminate of claim 1 , wherein the structured film further comprises a colorant.

12. The laminate of claim 1 , wherein the free ends of the upstanding posts comprise caps.

13. The laminate of claim 1 , wherein the structured film is a coextruded film having side-by-side first and second lanes, wherein the first lanes comprise the semi-crystalline polyolefin and at least one of the beta-nucleating agent or beta-spherulites of the semi-crystalline polyolefin, and wherein the second lanes comprise a different polymer composition.

14. The laminate of claim 13 , wherein the second lanes comprise an alpha-nucleating agent.

15. The laminate of claim 1 , wherein the structured film comprises the beta-nucleating agent, and wherein the beta-nucleating agent is selected from the group consisting of gamma quinacridone; aluminum salt of quinizarin sulphonic acid; dihydroquinoacridin-dione; quinacridin-tetrone; triphenenol ditriazine; the combination of calcium carbonate and organic acids; the combination of calcium stearate and pimelic acid; calcium silicate; dicarboxylic acid salts of metals of Group IIA of the periodic table; delta-quinacridone; diamides of adipic or suberic acids; calcium salts of suberic or pimelic acid; indigosol or cibantine organic pigments; quinacridone quinone; N′,N′-dicyclohexil-2,6-naphthalene dicarboxamide; anthraquinone red pigments; and bis-azo yellow pigments.

16. An absorbent article comprising the laminate of claim 1 .

17. The absorbent article of claim 16 , wherein the absorbent article has at least a front waist region, a rear waist region, and a longitudinal center line bisecting the front waist region and the rear waist region, and wherein at least one of the front waist region or the rear waist region comprises the laminate.

18. A method of making the laminate of claim 1 , the method comprising:
extruding a melt of a polyolefin and a beta-nucleating agent in the presence of a tool to provide a structured film having upstanding posts on a first surface of a backing;
cooling at least a portion of the structured film to a temperature sufficient to form beta-spherulites;
stretching the structured film containing beta-spherulites to provide porosity in the backing; and
joining a second surface of the backing to a carrier.

19. The method of claim 18 , wherein joining the second surface of the backing to the carrier comprises at least one of adhesive bonding, ultrasonic bonding, or surface bonding.

20. The method of claim 18 , wherein the stretching is carried out at a temperature in a range from 50° C. to 90° C.

Assignees

• 3M Innovative Properties Co

Inventors

• Chandrasekaran Neelakandan

Classifications

• B32B2555/02

  Diapers or napkins · CPC title

• B29C55/02

  of plates or sheets · CPC title

• B29K2105/0005

  containing compounding ingredients (releasing, lubricating or separating agents B29C33/56, fibers B29K2105/08, B29K2105/12; fillers B29K2105/16, recycled material B29K2105/26) · CPC title

• B32B2307/42

  Polarizing, birefringent, filtering · CPC title

• A61F13/15699 Primary

  Forming webs by bringing together several webs, e.g. by laminating or folding several webs, with or without additional treatment of the webs · CPC title