Kimberly-clark Worldwide, Inc.

Jose Siqueira

Howard Martin Welch

Wing-Chak Ng

Ann Louise McCormack

Oomman Painummoottil Thomas

Margaret Gwyn Latimer

Norman Earl Brown

James Austin

Stephen C Meyer

Bryan David Haynes

Tamara Lee Mace

Janis Wilson Hughes

Christian Lee Sanders

Lisa Sanabria

Christopher Laslie

Iris V Schumacher

Ann L Mccormack

An elastic nonwoven composite that contains an elastic film laminated to one or more nonwoven web materials is provided. The composite is formed by passing the film through a nip to bond the film to the nonwoven web material(s). Concurrent with bond formation, apertures are also formed in the elastic film. The apertures are of a size sufficient to provide a desired level of texture, softness, hand feel, and/or aesthetic appeal to the composite without having a significant adverse effect on its elastic properties. Aperture and bond formation are accomplished in the present invention by selectively controlling certain parameters of the lamination process, such as film content, bonding pattern, degree of film tension, bonding conditions, etc.

Nonwoven composite containing an apertured elastic film

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 nonwoven composite that exhibits latent elastic properties is provided. More specifically, latent elasticity may be imparted by blending a thermoplastic elastomer with a polyolefin that is capable of forming semi-crystalline domains among the amorphous elastomeric chains, and then forming a film from the blend. The film is then stretched in one or more directions to orient the amorphous elastomer chains. Without intending to be limited by theory, the present inventors believe that the oriented state of the amorphous chains may be held in place by the relatively stiff semi-crystalline olefin domains. Subsequently, the stretched film may be activated (e.g., heated) to shrink the film and provide it with 'latent' stretchability. For instance, the stretched film may be heated at or above the softening temperature of the polyolefin to soften the crystalline domains and allow the amorphous chains to return to their unoriented state. As a result of the present invention, the elastic film may be extended and recover from its unoriented state.

Latent elastic nonwoven composite

Growing community of inventors

Roswell, GA, United States of America

Jose Siqueira