Kimberly-clark Worldwide, Inc.

James Austin

Oomman Painummoottil Thomas

Howard Martin Welch

Jose Siqueira

Stephen C Meyer

Bryan David Haynes

Wing-Chak Ng

Lisa Sanabria

Christopher Laslie

C Allen Smith

Iris V Schumacher

Jose A Siqueira

An elastic composite formed from a laminate that contains an elastic film and a lightweight nonwoven facing having a low strength in the cross-machine direction ('CD') is provided. Due to the low strength of the facing, it is desirable that the elastic film have a sufficient thickness and weight to enhance the strength of the resulting composite. Unfortunately, the ability to join an elastic film to such a lightweight nonwoven facing becomes increasingly difficult as the thickness of the film increases. In this regard, the present inventors have discovered that a second laminate may be employed in the elastic composite that is formed from a thermoplastic film and nonwoven facing to impart increased strength to the composite. The film and facing of the second laminate may be formed from the same or different materials than the film and facing of the first laminate. Regardless, the laminates are positioned so that the elastic and thermoplastic films are in a face-to-face relationship. Through selective control over the polymer content and thickness, the present inventors have discovered that the elastic and thermoplastic films may be readily joined together under light pressure, even at ambient temperature conditions. This avoids the application of a substantial amount of heat used in conventional calender bonding processes, which can otherwise damage the film, and also minimize the need for costly adhesives.

Elastic composite formed from multiple laminate structures

An elastic composite formed from a lightweight nonwoven facing that has a low degree of strength in the cross-machine direction ('CD') is provided. Through selective control over certain parameters of the materials employed in the composite and the formation process, the present inventors have discovered that such low strength and lightweight facings may be readily laminated to an elastic film without significantly damaging their integrity. For example, in one embodiment, the elastic film may possess a multi-layered construction that includes an elastomeric elastic layer positioned adjacent to a strength-enhancing thermoplastic layer. The polymer content and thickness of the thermoplastic layer are generally selected to impart additional strength and integrity to the film. Likewise, the polymer content of the elastic layer may also be selected so that the film possesses a sufficient tack for adhering to the facing. In certain cases, it may be desirable to position the layer between two elastic layers so that the strength-enhancing layer does not substantially contact the nonwoven facing. In this manner, the strength-enhancing layer may avoid substantial damage during the lamination process.

Elastic composite containing a low strength and lightweight nonwoven facing

A nonwoven web material that contains an elastic component is provided. The elastic component contains a crosslinked network formed from a linear block copolymer having a monoalkenyl aromatic midblock positioned between conjugated diene endblocks (e.g., butadiene-styrene-butadiene ('B-S-B') triblock copolymer). Prior to crosslinking, such linear block copolymers have a relatively low viscosity and thus may be readily formed into a precursor elastic component that is subsequently crosslinked to achieve the desired elastic and mechanical properties. Crosslinking is typically achieved through the formation of free radicals (unpaired electrons) that link together to form a plurality of carbon-carbon covalent bonds at the conjugated diene endblocks.

Nonwoven web material containing a crosslinked elastic component formed from a linear block copolymer

A technique for imparting latent elasticity to components of an absorbent article is provided. More specifically, a latent elastic film that contains a crosslinkable semi-crystalline polyolefin is initially incorporated into an absorbent article. The film is not highly elastic prior to crosslinking and is thus dimensionally stable. Consequently, the film need not be maintained in a mechanically stretched condition during attachment to other components of the absorbent article, which provides for greater freedom in the location and manner in which the components are attached together. Once incorporated into the absorbent article, the semi-crystalline polyolefin is crosslinked to form a three-dimensional network having elastic memory. The film may also be heat activated, either through crosslinking or an additional step, to cause the film to shrink and further improve its stretch characteristics.

Absorbent article containing a crosslinked elastic film

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Johns Creek, GA, United States of America

James Austin