MX2008007539A - Filament-meltblown composite materials, and methods of making same - Google Patents

Abstract

An elastic composite material that does not require facing materials. The elastic composite material includes a first elastic meltblown layer, an array of continuous filament strands deposited on the first elastic meltblown layer, and a second elastic meltblown layer deposited on the continuous filaments strands opposite the first elastic meltblown layer. One or both meltblown layers and/or the continuous filament strands may include an elastic polyolefin-based meltblown polymer having a degree of crystallinity between about 3%and about 40%. Also included is a method of making the elastic composite material.

Description

MATERIALS COMPOSED OF BLOWED FILAMENTS WITH FUSION, AND METHODS TO MAKE THEMSELVES FIELD OF THE INVENTION The present invention relates to meltblown filament composites for use in or in various personal care products, and other products that require stretchability, and manufacturing methods for making such meltblown filament composite materials.

BACKGROUND OF THE INVENTION Stretched bonded laminates are commonly used in the manufacture of personal care products to provide stretch capacity. The term "stretched bonded laminate" refers to a composite elastic material made in accordance with a tie-rolling process, for example, the elastic layer (s) are joined together with additional coating layers. when only the elastic layer is in an extended condition (such as by at least about 25% of its relaxed length) so that upon relaxation of the layers, the additional layer (s) is / are accumulated (s). Such laminates usually have machine direction (MD) stretching properties and may subsequently be stretched to the extent that the additional (typically non-elastic) material accumulated between the bonded locations allows the elastic material to elongate. One type of stretched bonded laminate is described, for example, by U.S. Patent No. 4,720,415 issued to Vanderielen et al., In which multiple layers of the same polymer produced from multiple banks of extruders are used. Other composite elastic materials are described in U.S. Patent No. 5,385,775 issued to Wright and the copending Patent Publication of the United States of America No. 2002-0104608, published August 8, 2002, each of which is incorporated herein by reference. which is incorporated by reference herein in its entirety. Such stretched bonded laminates may include an elastic component that is a fabric, such as a meltblown fabric, a film, an array / series of continuous filaments generally parallel (either extruded or preformed), or a combination of such . The elastic layer is attached to a stretched condition to two extensible or inelastic nonwoven facing materials, such that the resultant laminate is imparted with a textured feel that is pleasing to the hand. In particular, the elastic layer is joined between two layers of coating, as long as the coating layers sandwich the elastic layer. In some instances, the cumulative coating layers may also be tapered, such that the stretched bonded laminate is actually a narrow stretched bonded laminate which may have some extension / elasticity in the cross machine direction (CD).

Such stretched bonded laminates can be used to provide elasticity to various components of a personal care product and with the added benefit of the feel similar to the pleasant fabric, such as a diaper liner or outer cover, a web material for the diaper waist, a diaper pack (fold) material for the diaper leg, diaper ears parts (that is, the attachment point of a diaper fastener system), as well as side panel materials for diapers and underpants for children's learning. Because such materials often come into contact with the skin of a human body, it is desirable that such materials be relatively soft to the touch, rather than rubberized in their feel (a common feeling for elastic materials). Such materials in the same way can provide elasticity and comfort for materials that are incorporated into protective workwear, such as surgical gowns, face masks and covers, lab coats, protective outer coats, such as covers for boats, grills, or cars.

Even though such stretched and soft materials have helped in making such elastic materials friendlier, there is still a need for such products that can be made in an efficient one step manufacturing process. In the same way there is also a need for such a laminated material which has reduced variability and aging of rolled up compared with the drawn stretched laminates. In the same way there is a need for a laminated material that provides reduced stiffness as a result of lamination of the coating layers in the laminate. Such a laminate can be more efficient in its use as an elastic material, in addition the removal of coating layers can be cost effective. Such a laminate can provide ease of use / extension, with better ability to retract because there will be no pulling of extra coating layers. Essentially, such a laminate can provide for higher levels of shrinkage with lower polymer weights. However, even with all these perceived benefits, to date an elastic composite material that is free of coating layers has been elusive due to manufacturing challenges.

Many adhesives themselves are typically somewhat elastic, and tend to retain some level of tack even after they are dry or cured. As a result, due to its inherent tackiness, it has been necessary, at least with respect to the laminated bonded laminates based on fabric, film, and filament, to use coatings on both sides of the central elastic component (e.g. filament), to avoid roll blocking during processing / storage. For the purposes of this application, the terms "roll lock" and "roll stick" shall be used interchangeably, and shall relate to the bow density of sticky films, sticky filament arrangements or other materials of sticky sheet to stick themselves when being rolled up for storage, before its final use. Such a roll lock can prevent the use and of material contained in a roll, a result of the inability to untangle such rolled material when it is really needed. In laminated filament-based bonded laminates, the adhesive is often applied to the coating layers themselves, and then the coating layers are combined at a pressure point with the filament array between them. Such an arrangement can generally be described as an ABA laminate, where A is a coating layer and B is an elastic layer.

While it may be desirable to reduce the basis weight of the stretched bonded laminate such that the material is less expensive and more flexible, it has been unclear from now on how to remove the coating layers without causing the wound material to stick, if it should be be stored before use. It is therefore desirable to have an elastic composite material that is free of coating layers that demonstrate acceptable elastic performance, but that is also capable of being stored in a roll without concern for roll blocking. It is also desirable to have a material that can be held in a roll under acceptable storage conditions, such as for a given period of time, and over a range of temperatures. It is to such needs that the current invention is directed.

SYNTHESIS OF THE INVENTION An elastic composite material capable of being rolled up for storage, and unrolling from a roll when needed for use, includes a blown first layer with elastic melting, an elastic layer of an array of continuous filament strips deposited on the first blown layer with elastic fusion, and a second layer blown with elastic fusion deposited in the continuous filament strips opposite the first blown layer with elastic fusion. The elastic composite material includes an elastic polyolefin-based polymer having a degree of crystallinity between about 3% and about 40%, or between about 5% and about 30%. The elastic polyolefin-based polymer can have a melt flow rate of between about 10 and about 60 grams for 10 minutes, or between about 60 and about 300 grams for 10 minutes, or between about 150 and about of 200 grams per 10 minutes; a melting point / softness of between about 40 ° C and about 160 ° C; and / or a density of about 0.8 to about 0.95, or about 0.85 to about 0.93, or about 0.86 to about 0.89 grams per cubic centimeter. The elastic poly olefin-based polymer may include polyethylene, polypropylene, butene, or octene homo- or copolymers, ethylene methacrylate, ethylene vinyl acetate, acrylate butyl copolymers, or a combination of any of these polymers. The elastic polyolefin-based polymer can be used to form one or both melt blown layers and / or the continuous filament strips.

When at least one of the melt-blown layers includes the elastic polyolefin-based polymer, the elastic composite appropriately has an interlayer peel strength that is less than a cross-layer peel strength of the composite material. For example, when the elastic composite material that is rolled on itself, it can be disentangled for future use without the outer surfaces of the material being acquired with each other on the roll. Therefore, the elastic composite material may not require any post-calendering treatment such as a non-blocking agent or the like.

In still fur alternate incorporation, the elastic composite material includes an adhesive between the array of continuous filament strips and at least one of the melt blown layers demonstrating a relatively short open time, such as an open time of between about 0.2 seconds and 1 minute, or between about 0.2 seconds and 3 seconds, or between about 0.5 seconds and 2 seconds. In yet another alternate embodiment, such an elastic composite material that includes an adhesive between the array of continuous filament strips and at least one of the meltblown layers, wherein the adhesive is applied in an amount of less than about 16 grams per square meter, or less than about 8 grams per square meter, or less than about 4 grams per square meter, or between about 1 and 4 grams per square meter.

The first and / or the second elastic meltblown layer may be a single layer of meltblown material or, alternatively, may include two or more layers. For example, one of the layers may include a melt blown polymer based on elastic polyolefin having a degree of crystal dignity of between about 3% and about 40%, or between about 5% and about 30%, and another layer may include a melt blown polymer based on styrenic block copolymer.

In certain embodiments of the invention, the elastic composite material has a total basis weight of between about 10 grams per square meter and 100 grams per square meter, or between about 20 grams per square meter and 90 grams per square meter, or between around 30 grams per square meter and 50 grams per square meter.

The invention also includes a method for producing an elastic composite, the method includes providing a meltblown first layer, depositing an array of continuous filament strips on the first blown layer with elastic fusion, and depositing a second layer blown with elastic fusion in the continuous filament strips opposite the first blown layer with elastic fusion. The elastic composite material may or may not be calendered. Even when the resulting material does not have coating layers the elastic composite material, the resulting elastic composite material can be wound onto a roll without experiencing roll blocking.

An elastic composite material, as described herein, for use in a personal care or other stretchable article is also contemplated by the invention. In certain embodiments in particular, the elastic composite material is incorporated into a personal care article adjacent to an opening for a part of the body.

BRIEF DESCRIPTION OF THE DRAWINGS The invention may be better understood by reference to the following description of the embodiments of the invention taken in conjunction with the accompanying drawings, wherein: Figure 1 illustrates a method of manufacturing an elastic composite material according to the invention.

Figure 2 illustrates a cross-sectional view of an incorporation of an elastic composite material.

Figure 3 illustrates a cross-sectional view of another embodiment of an elastic composite material.

Figure 4 illustrates an alternate method of manufacturing an elastic composite material according to the present invention.

Figure 5 illustrates a personal care product using an elastic composite material made in accordance with the invention.

DEFINITIONS Within the context of this application, each term or phrase below may include the following meaning or meanings.

As used herein, the term "personal care item" means diapers, underpants for learning, swimsuits, absorbent undergarments, incontinence products for adults, and products for hygiene. woman, such as pads for the care of women, napkins and linings for panties. While a diaper is illustrated in FIG. 5, it should be recognized that the inventive material can just as easily be incorporated into any of the personal care articles previously listed as an elastic component. For example, such material can be used to be elastic side panels of underpants for learning.

As used herein, the term "protective outer garment" means garments used for protection in the workplace, such as surgical gowns, hospital gowns, gowns, lab coats, masks, and all protective covers.

As used herein, the terms "protective cover" and "protective outer cover" mean the covers that are used to protect objects such as, for example, a cart, a boat and the covers of grills for roasting, as well as agricultural fabrics.

As used herein, the terms "polymer" and "polymeric" when used without descriptive modifiers, generally include but are not limited to, homopolymers, copolymers, such as, for example, alternating, random copolymers of grafting and block, terpolymers, etc. and the mixtures and modifications thereof. Additionally, unless otherwise specifically limited, the term "polymer" includes all possible spatial configurations of the molecule. These configurations include, but are not limited to, random, syndiotactic and isotactic symmetries.

As used herein, the terms "machine direction" or MD means the direction along the length of a web in the direction in which it is produced. The terms "transverse machine direction", "transverse direction", or CD mean the direction across the width of the fabric, for example an address generally perpendicular to the machine direction.

As used herein, the term "melt blown" means the fibers formed by extruding a molten thermoplastic material through a plurality of usually circular, thin capillary vessels such as filaments or fused wires in gas streams (eg, air) at high Converging velocity which attenuate the filaments of molten thermoplastic material to reduce its diameter, which can be microfiber diameter. Then, the meltblown fibers are transported by the high velocity gas stream and are deposited on a collection surface to form a randomly dispersed meltblown fabric. Such process is described in several patents and publications that include Report NRL 4364, "Manufacture of Super-Fine Organic Fibers" by B.A. Wendt, E.I. Boone and D.D. Fluharty; Report NRL 5265, "An Improved Device for the Formation of Super-Fine Thermoplastic Fibers" by K.D. Lawrence, R.T. Lukas, J.A. Young; and in U.S. Patent No. 3,849,241 issued November 19, 1974 to Butin and others incorporated by reference herein in its entirety.

As used herein, the terms "sheet" and "sheet material" should be interchangeable and in the absence of a modifier word, refer to woven materials, non-woven fabrics, polymeric films, canvas-like materials polymeric, and polymeric foam canvases.

The basis weight of non-woven films is usually expressed in ounces of illegal material per square yard (osy) or in grams per square meter (g / m2 or gsm) and fiber diameters are usually expressed in microns. . (Note that to convert from ounces per square yard to grams per square meter, ounces per square yard are multiplied by 33.91). The thickness of the film can also be expressed in microns or in thousandths of an inch.

As used herein, the term "laminate" refers to a structure composed of two or more layers of sheet material that have been adhered through a bonding step, such as through the adhesive bond, the thermal bond, point bonding, compression bonding, extrusion coating or ultrasonic bonding.

As used herein, the term "elastomeric" should be interchangeable with the term "elastic" and refers to the sheet material which, upon application of a stretching force, is stretchable in at least one direction (such as the cross machine direction), and which at the release of the drawing force contracts / returns approximately to its original dimension. For example, a stretched material having a stretched length which is at least 50% greater than its length without relaxed stretching, and which may be recovered to within at least 50% of its stretched length upon release of force of stretched. A hypothetical example may be a sample of one (1) inch of a material which is stretched to at least 1.50 inches and which, upon release of the drawing force, may be recovered at a slowness of no more than 1.25 inches. . Desirably, such an elastomeric sheet contracts or recovers up to 50% of the stretched length in a particular direction, such as in either the machine direction or the cross machine direction. Even more desirably, such an elastomeric sheet material recovers up to 80% of the stretched length in a particular direction, such as either the machine direction or the cross machine direction. Even more desirably, such an elastomeric sheet material recovers more than 80% of the stretched length in a particular direction, such as in either the machine direction or the cross machine direction. Desirably, such an elastomeric sheet that is stretchable and recoverable in both directions is the machine direction and the cross machine direction.

As used herein, the term "elastomer" should refer to a polymer which is elastomeric.

As used herein, the term "thermoplastic" should refer to a polymer which is capable of being processed molten.

As used herein, the term "inelastic" or "non-elastic" refers to any material which does not fall within the above definition of "elastic".

As used herein the term "thermal spot bonding" involves passing a fabric or fabric of fibers to be joined between a hot calender roll and an anvil roll. The calender roll is usually, but not always, patterned in some way so that the entire fabric is not bonded across its entire surface, and the anvil roller is usually flat. As a result, several calendered roller patterns have been developed for functional as well as aesthetic reasons. An example of a pattern has points and is the Hansen Pennings pattern or "H &P" with about 30% area joined with about 200 joints per square inch as taught in the United States of America patent No. 3,855,046 issued to Hansen and Pennings, incorporated herein by reference in its entirety. The H &P pattern has bolt or square point joining areas where each bolt has a side dimension of 0.038 inches (0.965 millimeters), a separation of 0.070 inches (1.778 millimeters) between bolts, and a bond depth of 0.023 inches (0.584 millimeters). The resulting pattern has a bond area of about 29.5%. Another typical point union pattern is the expanded Hansen Pennings junction pattern or "EHP" which produces a 15% bond area with a square bolt that has a side dimension of 0.037 inches (0.94 millimeters), a bolt gap of 0.097 inches (2.464 millimeters) and a depth of 0.039 inches (0.991 millimeters). Another typical union pattern designated "714" has square bolt joint areas where each bolt has a side dimension of 0.023 inches, a gap of 0.062 inches (1,575 mm) between bolts, and a joint depth of 0.033 inches (0.838) millimeters). The resulting pattern has a bound area of around 15%. Yet another common pattern is the C-Star pattern which has a binding area of about 1.69%. The C-Star pattern has a transversal direction bar or "corduroy" design interrupted by shooting stars. Other common patterns include a diamond pattern with slightly out-of-phase diamonds and repeating with about 16% area of bond and a woven wire pattern that looks like the name suggests, for example as a window screen pattern on the range from about 15% to about 21% and about 302 joints per square inch.

Typically, the percentage of bond area varies from about 10% to about 30% of the area of the laminate of the fabric. As is well known in the art, the joint in place holds the laminated layers together as well as imparts integrity to each individual layer by bonding filaments and / or fibers within each layer.

As used herein, the term "ultrasonic" means a process effected, for example, by passing the fabric between a sonic horn and an anvil roller as illustrated in U.S. Patent No. 4,374,888 issued to Bornslaeger, incorporated by reference here in its entirety As used herein, the term "adhesive bond" means a bonding process which forms a bond by the application of an adhesive. Such adhesive application may be by various processes such as slot coating, spray coating and other topical applications. In addition, such an adhesive can be applied within a product component and then exposed to a pressure such that the contact of a second product component with the adhesive containing the product component forms an adhesive bond between the two components.

As used herein, the term "post-calendering treatment" is required to any treatment, such as the application of a non-blocking agent, which is typically applied to a laminate towards the end of the rolling process, such as following the Lamination path through a pressure point or on a calendering roller, in order to reduce the interlayer peel strength.

As used herein, the term "interlayer peel strength" refers to the peel strength required to separate a laminate from itself when it is untangled from a roll, as opposed to the peel strength between two layers within the laminate. The interlayer peel strength can be rmined using the Roll Locking Test Method described in il below.

As used herein, and in the claims, the term "comprising" is inclusive or open ended and does not exclude additional non-recited elements, compositional components, or steps of the method. Therefore, such a term is intended to be synonymous with the words "has", "have", "have", "includes", "includes", and any derivatives of these words.

As used herein, the terms "extensible" or "expandable" mean stretchable in at least one direction, but not necessarily recoverable.

Unless stated otherwise, the percentages of the components in the formulations are by weight.

ILED DESCRIPTION OF THE INVENTION For the purposes of this invention, an elastic composite material does not include coating layers. More particularly, the appropriate elastic composite material includes a blown first layer with elastic fusion, an array of continuous filament strips deposited on the first blown layer with elastic fusion, and a second blown layer with elastic fusion deposited on the opposite continuous filament strips to the first layer blown with elastic fusion, as illustrated in Figures 1 and 2. Although the elastic composite material does not have coating layers, the composite material may be attached to one or more additional layers to provide elasticity to the additional layers. However, the elastic composite material and the additional layers, when bonded, do not form laminates, per se. More particularly, the additional layers are not co-terminal with the elastic composite material. Instead, it is contemplated that the elastic composite material, free of any coating layers, may be attached to additional layers to provide elasticity and in the isolated regions of the articles, such as in a personal care article adjacent to a opening for a part of the body, mainly around the opening for the waist, the opening for the legs, or the like.

The composite material appropriately includes an elastic polyolefin-based polymer having a degree of crystallinity between about 3% and about 40%, or between about 5% and about 30%, or between about 15% and about 25% The elastic polyolefin-based polymer can also have a melt flow rate of between about 10 and about 600 grams for 10 minutes, or between about 60 and about 300 grams for 10 minutes, or between about 150 and around 200 grams for 10 minutes; a melting point / softness of between about 40 ° C and about 160 ° C; and / or a density of about 0.8 to about 0.95, or between about 0.85 to about 0.93, or about 0.86 to about 0.89 grams per cubic centimeter. An elastic polyolefin-based polymer possessing some or all of these properties has been shown to reduce or eliminate roll blocking in the elastic composite materials described herein. The elastic polyolefin-based polymer may include polyethylene, polypropylene, butene, or octene homo-copolymers, ethylene methacrylate, ethylene vinyl acetate, acrylate butyl copolymers, or a combination of any of these polymers.

An example of an appropriate elastic polyolefin-based polymer is VISTAMAXX, such as VM2210, available from ExxonMobil Chemical of Baytown, Texas. Other examples of suitable polyolefin-based polymers include the EXACT plastomer, the ethylene methacrylate OPTEMA, and the polyisobutylene VISTANEX, and the catalyzed metallocene polyethylene, all available from ExxonMobil Chemical, as well as the AFFINITY polyolefin plastomers, such as the AFFINITY EG8185 or AFFINITY GA1950, available from the Dow Chemical Company of Midland, Michigan; ethylene vinyl acetate ELVAX, available from E.I. Du Pont de Nemours and Company of Wilmington, Delaware; and ESCORENE Ultra ethylene vinyl acetate, available from ExxonMobil.

The appropriate elastic polyolefin-based polymer has a slow crystallization rate, with partial regions of amorphous and crystalline phases making it inherently elastic and sticky. The elastic polyolefin-based polymer can be incorporated with one or both of the elastic melt blown layers and / or the continuous filament strips, as described in more detail below.

It is desirable that such an elastic composite material demonstrate a stretch-to-arrest value of between about 30% and 400%. In an alternate embodiment, such material demonstrates a stretch value to arrest of between about 50% and 30%. In still further alternating incorporation, such a composite material demonstrates a stretch-to-arrest value of between about 80% and 250%.

Additional components may be included in the elastic composite material, such as a film, an elastic canvas or net structure, a foam material, or a combination of any of the above materials. If a film is used, this can be a perforated film. In certain embodiments, any of these additional components may be used in place of the arrangement of the continuous filament strips.

At least one of the components of the elastic composite material can be formed of an elastic polyolefin-based polymer having a degree of crystallinity of between about 3% to about 40%, or about 5% and about 30%. %, or between around 15% and around 25%, as previously described. When the elastic copolymer is used to form one or both of the meltblown layers, for example, the slow crystallization rate of elastic polymer is advantageous because the meltblown fibers are semi-sticky while they are deposited on the forming wire, which keeps the elastic strips in place and adhesively bonds the compound. Additionally, when the melt blown layer (s) includes the elastic polymer, the meltblown layer (s) may be applied to the top aggregate compared to the non-elastic meltblown layers. Additionally, the superior aggregate of the elastic melt blown together with the elastic melt blown tack helps to better secure the filaments between the meltblown layers such that in the filaments they are less likely to become loose, as demonstrated by the resistance to melting. peeling of interlayers that is greater than the peel strength of interlayer. More particularly, the peel strength of the components within the composite is greater than the peel strength of the outer surfaces of the composite itself when the composite material is disentangled from a roll. The superior aggregate of elastic meltblown can also help reduce porosity compared to bonded stretched laminates of a comparable total basis weight manufactured with spin-bonded liners.

Another benefit of using the elastic polyolefin-based polymer in the meltblown layer of the reduction or elimination of the rollblock, as demonstrated by the interlayer peel strength of the composite material. In addition to preventing blockage in rolls, the elastic polyolefin-based polymer can also be stretched with elastic filament strips. Other laminates may include post-calendering treatment, such as non-elastic polypropylene melt blown dedusting, to prevent roll blocking, but incorporation of the elastic polymer into the melt blown layer and may remove the need for any treatment of post-calendering.

One or both of the melt blown layers may include, for example, between about 30% and about 100%, or between about 50% and about 80%, by weight of elastic polyolefin-based polymer. One or both of the meltblown layers can be a single layer or a multi-layer component. For example, the melt blown layer (s) may also include a melt blown polymer layer based on styrenic block copolymer, as described in more detail below.

As mentioned, the continuous filament strips may also include an elastic polyolefin-based polymer. More particularly, the continuous filament strips may be composed of between about 5% and about 90%, or between about 30% and about 70%, by weight of the elastic polyolefin-based polymer.

Additionally, any or all of the blank components of the elastic composite material (either melt blown layer (s), regulations or other components) may include thermoplastic materials such as block copolymers having the general formula ABA 'wherein A and A' are each a final block of thermoplastic polymer which contains a styrenic moiety such as a polyvinyl arene and where B is a middle block of elastomeric polymer such as a conjugated diene or an alkene polymer lower.

Specific examples of useful styrenic block copolymers include hydrogenated polyisoprene copolymers such as styrene-ethylenepropylene-styrene (SEPS), styrene-ethylenepropylene-styrene-ethylenepropylene (SEPSEP), hydrogenated polybutadiene polymers such as styrene-ethylenebutylene -styrene (SEBS), styrene-ethylenebutylene-styrene-ethylenebutylene (SEBSEB), styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), and hydrogenated polyisoprene / butadiene polymer such as styrene-ethylene-ethylenepropylene-styrene (SEEPS). Block polymer configurations such as diblock, triblock, multiblock, star and radial are also contemplated in this invention. In some instances, higher molecular weight block copolymers may also be desirable. Block copolymers are available from Kraton Polymers US. LLC of Houston, Texas, under the Kraton G or D polymer designations, eg G1652, G1657, G1730, D1114, D1155, and D1102 and Septon Company of America, Pasadena, Texas, under the designations Septon 2004, Septon 4030, and Septon 4033. Other potential suppliers of such polymers include Dexco Polymers of Texas and Dynasol of Spain. Mixtures of such elastomeric resin materials are also contemplated as the primary component of the elastic layer. Additionally, other desirable block copolymers are described in U.S. Patent Publication No. 2003 / 0232928A1 which is incorporated by repellency herein in its entirety.

Such base resins can be additionally combined with glutinizing and / or processing aids in compounds. Exemplary compounds include but are not limited to KRATON G 2760, and KRATON G 2755. Processing aids that can be added to the elastomeric polymer described above include a polyolefin to improve the processability of the composition. The polyolefin must be one whichWhen it is thus mixed and subjected to an appropriate combination of high pressure and high temperature conditions, it is extruded, in mixed form, with the elastomeric base polymer. Useful mixed polyolefin materials include, for example, polyethylene, polypropylene and polybutene, including ethylene copolymers, propylene copolymers and butene copolymers. A particularly useful polyethylene can be obtained from Eastman Chemical under the designation EPOLENE C-10. Two or more of the polyolefins can be used. Extrudable blends of elastomeric polymers and polyolefins are described in, for example, U.S. Patent No. 4,663,220 herein incorporated by reference in its entirety.

The elastomeric filaments may have some tack / tack to improve the autogenous bond. For example, the elastomeric polymer itself can be tacky when formed into films, and / or filaments or, alternatively, a compatible glutinizing resin can be added to the above described extrudable elastomeric compositions to provide glutinizing elastomeric fibers and / or bonded filaments. in an autogenous way. With respect to glutinizing resins and glutinizing extrudable elastomeric compositions, note the resins and compositions as described in U.S. Patent No. 4,787,699 herein incorporated by reference in its entirety.

Any glutinizing resin can be used which is compatible with the elastomeric polymer and can withstand higher processing temperatures (e.g. extrusion). If the elastomeric polymer (for example elastomeric block copolymer A-B-A) is mixed with processing aids such as, for example, polyolefins or spreading oils, the glutinizing resin should also be compatible with those processing aids. Generally, hydrogenated hydrocarbon resins are preferred glutinizing resins, because of their better temperature stability. The glutinizers of the REGALREZ series are examples of such hydrogenated hydrocarbon resins. REGALREZ hydrocarbon resins are available from Eastman Chemical. Of course, the present invention is not limited to the use of such glutinizing resins, which are compatible with the other components of the composition and can withstand the higher processing temperatures can also be used. Other glutinizers are also available from ExxonMobil under the ESCOREZ designation.

Other exemplary elastomeric materials that may be used include polyurethane elastomeric materials such as, for example, those available under the trademark TINY from Noveon, elastomeric polyamide materials such as, for example, those available under the trademark PEBAX (amide of polyether) from Ato Fina Company, and polyester elastomeric materials such as, for example, those available under the HYTREL brand name of E. I. DuPont De de Nemours & Company Useful elastomeric polymers also include, for example, elastic polymers and copolymers of ethylene and at least one vinyl monomer such as, for example, vinyl acetates, unsaturated aliphatic monocarboxylic acids, and the esters of such acids monocarboxylic The elastic copolymers and the formation of the elastomeric melt blown fibers of these elastic copolymers are described, for example, in United States of America Patent No. 4,803,117 incorporated herein by reference herein in its entirety.

Additional materials which can be used in the elastic composite, such as in the melt blown layers and / or the continuous filament strips, to provide some extensibility with limited recovery, include the single site catalyzed polyolefin materials, such such as metallocene catalyzed polyolefins and constricted geometry polyolefins, as available from Dow under the designation AFFINITY and ExxonMobil, under the designation EXACT. Desirably, such materials have densities of less than 0.89 grams per cubic centimeter.

Finally, the previously formed elastic strips are also contemplated to be within the scope of this invention. Such preformed strips, such as solution treated materials, include LYCRA, available from Invista of Wichita, Kansas; GLOSPAN, available from Globe Manufacturing Co. , of Fall River, Massachusetts; and FULFLEX, available from Fulflex Elastomerics Worldwide of Lincoln, Rhode Island. This material can serve as the basis of a continuous filament arrangement component, or alternatively a film component, of the elastic composite material.

The filaments, either extruded or preformed, may be round with a circular cross section, or may have several other shapes in cross section. For example, in certain embodiments, flat strips or strips, which have a square, rectangular, or other cross section that carries a flat appearance to the strips, may be included. Long strips can provide better control during entanglement, for example.

Typically, the mixture used to form the fabric, the film or the filaments when such are made of an extruded material in an on-line process, include for example, from about 40% to about 90% by weight of polymer base resin elastomeric, from about 0% to about 40% polyolefin processing aid, and from about 5% to about 40% glutinizing resin. These proportions can be varied depending on the specific properties desired and the polymers used. For alternate incorporation, such a mixture includes between about 60% and 80% base resin, between about 5% to 30% processing aid, and between about 10% and 30% glutinizing. In a further alternate incorporation, such a blend includes a glutinizer in an amount of between about 10% and 20% glutinizing.

The elastic composite material can be made using several methods. In particular, the material can be made using either a joining and extrusion method with a meltblown layer based on elastic polyolefin having a slow rate of crystallization, or an application of a previously bonded adhesive having an open time relatively inferior and a post-bonded application of such an adhesive, with the adhesive becoming non-tacky followed by the application. The various methods can be described in an embodiment as involving a binding agent, even though all of the methods do not involve "adhesives" per se. The methods can be characterized in various ways as involving mechanical entanglement which, in effect, mechanically joins the layers together without a sticky result.

The attributes of a semi-tacky elastic polyolefin-based melt-blown layer having a lower crystallization rate are described above. More particularly, the meltblown fibers are semi-sticky when they are deposited on a forming wire, which holds the elastic strips in place and adhesively bonds the compound. Additionally, the elastic meltblown layers can be applied to a relatively higher aggregate, which contributes to the bond between the meltblown layers and the filaments.

If an adhesive method is used to create such elastic composite materials, it is desirable that such an adhesive have a relatively short open time of between about 0.2 seconds (sec) and 1 minute. In an alternate embodiment, such open time is between about 0.2 seconds and 3 seconds. In still an additional alternate incorporation, such open time is between about 0.5 seconds and 2 seconds. An example adhesive with such properties is a hot melt adhesive based on polypropylene (which becomes non-tacky just after application, upon solidification) including up to 65% or between about 15% to 40% atactic polypropylene, in an incorporation around 50% by weight of Huntsman H2115 (atactic polypropylene from Huntsman Polymers); between around 20% to 50% of glutinizing, in an incorporation around 30% of ESCOREZ 5300 of ExxonMobil; between about 2% to 10% of styrenic block copolymer, in about 4% incorporation of SEPTON 2002 from Septon Polymers; between about 10% to 20% isotactic polypropylene, in one embodiment, about 16% of PP 3746G (isotactic polypropylene) also from ExxonMobil; between about 0% to 2% of coloring agent, in about 2% incorporation of a coloring agent, such as 50% titanium dioxide in VECTOR 4411 and finally; between about 0.2% to 1% stabilizer, in one embodiment, about 0.5% of IRGANOX 1010 from Ciba Specialty Chemicals. It should be appreciated that the various components may have other substitutes, such as stabilizers instead of IRGANOX. Additionally, it should be appreciated that such additives may also not contain coloring agents, depending on the application of the product. Other adhesives may be used with the present invention including those derived from the adhesives described in U.S. Patent Nos. 6,657,009; 6,774,069; and 6,872,784, and the Patent Publications of the United States of America Nos. 20020123538 and 20050054779, each of which is incorporated herein by reference in its entirety.

In one embodiment, it is desirable that the adhesive be applied in a pre-bond step (this is before (such as immediately before) bringing the melt blown layers and the continuous filament strips together at a pressure point) to a base weight of less than about 16 grams per square meter. In an alternate embodiment, such an adhesive is applied at a basis weight of less than about 8 grams per square meter. In still further alternate incorporation, it is desirable that such an adhesive has been applied at a basis weight of less than about 4 grams per square meter. In still further alternate incorporation, it is desirable that the adhesive be applied at between 1 and 4 grams per square meter. In one embodiment, it is desirable that such an adhesive be applied by spraying, such as through available ITW systems or other spraying applications. Such spraying application is in an embodiment sprayed in one of the layers, such as in one of the meltblown layers. In an alternate embodiment, such spraying is at the point of pressure at which the melt blown layers and the continuous filament strips are joined.

If the adhesive is to be applied as a pre-bonding and post-bonding step (previously joined as previously described), it is desirable that the adhesive be applied to the materials (as will be described below) in an amount of less than 4. grams per square meter before joining the various layers. In an alternate embodiment, such an adhesive is desirably applied in an amount of less than 2 grams per square meter before the bonding of the various layers. In yet another alternate embodiment, such adhesive is applied in a pre-bonding step in a range of between about 1 and 4 grams per square meter and in a post-joining step of between about 0 to 4 grams per square meter.

In one embodiment, a method for producing an elastic composite material utilizes two meltblown layers such as those that have been previously described, and an array of continuous elastic filaments bonded between the meltblown layers, such that the composite has a structure of ABA, in which "A" represents the elastic melt blown layers, and "B" represents the continuous elastic filaments. In such a way that the resulting material shows increased levels of stretching, as well as the ability of the material to be rolled up for storage on itself if it is not used immediately. The material in the same manner demonstrates an elastic shrinkage force augmented by the given basis weight since the elastic composite material is allowed to retract to a greater extent than is possible with one or two facing layers joined.

As can be seen in Figure 1, which illustrates a schematic view of a method for manufacturing an elastic composite material according to the invention, Figure 1 illustrates a continuous, horizontal filament laminate 10 manufacturing process. A first supply meltblown 20 is fed to a mixed polymer composition, such as the previously described materials, particularly an elastic polyolefin base polymer, from one or more supplies (not shown), which are extruded on a forming surface 30 (eg example, a perforated band) that moves from right to left around the rollers 40 in the form of a melt blown first layer 31. A vacuum (not shown) can help keep the blown fibers 31 against the system of perforated wire. Techniques for fiber extrusion, such as blowing with modified melting of the fibers, are further disclosed in the previously mentioned United States of America Patent No. 5,385,775 issued to Wright.

An array of continuous filaments 36 is extruded from a filament extrusion supply 35 into a meltblown first layer 31 on the forming surface 30. The extruded polymer is desirably a styrenic block copolymer elastomer and / or a base polymer. elastic polyolefin. In several embodiments, the extrusion apparatus 35, or an additional adjacent extrusion apparatus (shown), can be configured to produce other materials, for example a film, to achieve on-line placement of the layers thereof or of different materials. .

A meltblown second layer 46, also of an elastomeric material such as the previously described materials, particularly an elastic polyolefin-based polymer, is extruded from a second meltblown supply 45, such that the meltblown fibers 46 are placed on top of the continuous filaments 36 (array).

In one embodiment, each of the meltblown layers 31 and 46 is applied such that the combined meltblown layers represent about 30% to about 90% by weight basis of the elastic composite 70, for example. In a particular embodiment, the elastic polyolefin-based polymer composition thereof in both the filaments 36 and the meltblown materials 31 and 46. In an alternate embodiment, the compositions are different (which may include the same base resin , but different percentages of processing or glutinizing aids).

The meltblown filament / blow compound is set on the forming surface 30 and can be calendered through a pair of pressure point rolls 60 with minimal pull. More particularly, depending on the materials used, calendering may not be necessary. Alternatively, the composite material 70 may be slightly calendered using, for example, a rubber / steel lamination pressure point of approximately 25 pounds per linear inch with a pressure point width of 0.25 to 0.5 inches. The pressure point rolls 60 may be smooth and are suitably supplied with a surface having little or no affinity for the filaments or fibers. More particularly, the pressure point rolls 60 can be designed to provide 100% bond area through the use of flat calender rolls or they can provide a pattern bonding area. The rollers 60 can be heated to a degree below the melting / softness points of the various composite components, or they can be at room temperature, or cooled.

After the meltblown layers and the combined continuous filament strips leave the pressure point 60, the elastic composite 70 is then transported with minimal pull to a pickup roller 75 where the material is rolled up and stored for later use. All rollers that come into contact with the meltblown layers may include a non-tacky surface, such as a polytetrafluoroethylene (TEFLON) coating, or release liner, silicone rubber. Such rollers can additionally be coated with IMPREGLON coatings from Southwest Impreglon, of Houston, Texas, or Stowe-Woodward Silfex silicone rubber coatings of a hardness of 60 Shore A. In an alternate incorporation of this method composed of continuous filament arrangement , instead of extruding continuous filaments, previously formed elastic strips such as the LYCRA strips can be unraveled from a drum and fed at a calender pressure point lowered minimum tension.

The resulting elastic composite 70 can be manufactured in a one-step process at a lower cost than conventional drawn joined laminates because no coating materials are required, therefore the manufacturing process is streamlined and the material costs are reduced . Additionally, the elastic composite material can be rolled into a roll under minimum tension, which potentially minimizes roller aging continued and the variability of the roll continued to typically be associated with the drawn joined laminates.

Other methods for making the elastic composite 70 may include more than one step. For example, one or both of the meltblown layers may be preformed and unrolled from the rolls. Additionally, the elastic filaments 36 may be preformed instead of being extruded during the formation of the elastic composite 70. Therefore, the various methods may include two extruded meltblown and extruded filament layers; two extruded meltblown layers and preformed filaments; two preformed layers of meltblowing and extruded filaments; two preformed layers of meltblowing and previously formed filaments; an extruded meltblown layer with a pre-formed meltblown and extruded filament cover; or an extruded meltblown layer with a previously formed layer of meltblown and preformed filaments. As described herein, additional layers may also be included, and other forms of the elastic middle layer, such as the film, may be used in place of the filaments.

A structure of elastic composite material can be seen in Figure 2, which illustrates a stylized cross-sectional view of an elastic composite 80 according to the invention. As can be seen in the figure, the elastic melt blown first layer 85 may be located down / immediately adjacent the filament arrangement 87. The elastic melt blown second layer 89 is placed on top of the filament array 87 on an opposite side of the filament arrangement 87. that the first layer blown with elastic fusion 85.

The thickness of the various layers is not necessarily to scale, and they are exaggerated to illustrate their existence.

In one embodiment, the continuous filaments in such laminates are desirably present in an amount of between about 7 to 18, or about 8 to 15 per directional inch transverse. The basis weight of the meltblown material of the first blown supply with elastic melt can be up to about 34 grams per square meter, or between about 2 and 20 grams per square meter, at the rolling point. Similarly, the basis weight of the meltblown material of the second blown supply with elastic melt and can be up to about 34 grams per square meter, or between about 2 and 20 grams per square meter, at the rolling point.

As an example of an embodiment of the invention, the ABA structure compound can be produced according to the methods described above, with elastic components A and B, which desirably comprise the elastic melt blown layers and the filament arrangement, each one desirably includes an elastic polyolefin-based polymer, such as the VISTAMAXX available from ExxonMobil. Desirably, such a polymer blend also includes a blend composed of KRATON G polymer such as KRATON G 2760 or KRATON G 2755 in the filaments, if desired the same polymer blend in the elastic melt blown layers or a second polymer blend G in the melt blown layers. The weight ratio of the melt blown filaments may be in a 90:10 ratio, or other appropriate ratio.

Alternatively, instead of being a filament array, component B may be a film 92, as illustrated in FIG. 3. In yet another embodiment, component B may include both a filament array and a film (not shown). ). The film 92 may include a polymer based on elastic polyolefin. Examples of other suitable film materials include any of the elastomeric polymers described herein, particularly those with respect to the filament arrangement in previous incorporations, so long as the film has a basis weight of about 50 grams per square meter or less, or between about 35 to about 45 grams per square meter, or between about 38 and about 42 grams per square meter.

In the manufacture of the material for example, the following conditions were employed. A meltblown first layer was made with VISTAMAXX VM 2210 at a basis weight of approximately 33 grams per square meter (1 pound per inch per hour (PIH) at 30 feet per minute (fpm)). The first melt blown layer was unraveled and the KRATON G2760 filaments were extruded at a melt temperature of 475 ° F at a rate of 0.5 pounds per inch per hour of the melt blown first layer, which resulted in a base weight filament of approximately 16 grams per square meter. This material was then passed under another meltblown supply that extruded a second blown layer with VISTAMAXX VM2210 melt at approximately 1.0 pounds per inch per hour (32 grams per square meter) over the filaments, which resulted in a final weight compound base of approximately 82 grams per square meter. The extrusion temperature for VISTAMAXX VM2210 was 450 ° F. In an alternate embodiment of a method for making an elastic composite material, a vertically oriented extrusion platform can be used to extrude an elastic continuous filament array. In this embodiment, a bonding method with non-tacky adhesive can be used to bond the elastic continuous filament arrangement to the meltblown layers.

Figure 4 schematically illustrates a vertical filament laminate manufacturing process 100 for the manufacture of elastic composite materials 170 produced from an elastic composition. Referring to Figure 4, at least one molten elastomeric material 105, for example a styrenic block copolymer material, is extruded from a die extruder 110 through linking holes as a plurality of substantially continuous elastomeric filaments. The extruder can extrude at temperatures between about 360 ° F and 500 ° F. A film matrix for producing sheets or slats can also be used in alternate additions. The filaments 105 are submerged and solidified by passing the filaments 105 onto a first roller 120. The first roller 120 can be a cooling roller. Any number of cooling rollers can be used. Suitably, the cooling rolls can have a temperature between about 40 ° F to about 80 ° F. Alternatively, as shown in Figure 4, the first of them 120 may be a vacuum roll on which the first meltblown layer may be deposited, as described in more detail below.

The die of the extruder 110 can be positioned with respect to the first roll 120 so that the continuous filaments find this first roll 120 at a predetermined angle 130. This strip extrusion geometry is particularly advantageous for depositing a molten extrude on a rotating roll or drum. An angled, or inclined orientation provides an opportunity for the filaments to emerge from the die at a right angle at the tangent point of the roll, which results in improved bonding, more efficient energy transfer, and generally longer matrix life . This configuration allows the filaments to emerge at an angle of the die and follow a relatively straight path to contact the tangent point on the roll surface. The angle 130 between the die exit of the extruder 110 and the vertical axis (or the horizontal axis of the first roll, depending on what angle is measured) can be as little as a few degrees or as much as 90 °. For example, an extruded outlet of 90 ° to the roll angle can be achieved by placing the extruder 110 directly above the edge of the downstream of the first roll 120 and having a side exit die tip in the extruder. Moreover, angles such as around 20 °, around 35 ° can be used, or around 45 °, away from the vertical. It has been found that, when using a link plate orifice density per 12 inches of filament, a noble of about 45 ° (shown in Figure 4) allows the system to effectively operate. The optimum angle, however, can vary as a function of the extruded exit velocity, the roll speed, the vertical distance from the die to the roll, and the horizontal distance from the center line of the die to the top dead center of the roll. . Optimal performance can be achieved by employing various geometries to result in improved bonding efficiency and reduced filament breakage.

The meltblown layers 152 and 154 can be applied to the meltblown filaments 153 and 155 on opposite sides of the filaments 105, as shown in Fig. 4. More particularly, the meltblown first layer 152 can be applied from the melt blowing supply 153 to the vacuum roller 120. The first meltblown layer 152 and the filaments 105 can then be passed to the vacuum roller 145 onto which the second melt blown layer 154 can be applied from the supply blown with melting 155. The filaments and the meltblown layers are then combined to form the elastic composite material.

The composite material is then passed through the pressure point rolls 165 to join the elastic filaments 105 and the melt blown layers 152 and 154, thereby forming the finished composite 170.

While calendering the composite material is completely optional, the pressure point rollers may be designed to provide a patterned roller which can give certain benefits such as increased stretch or bulk of the composite and can be used where the resistance of the contact adhesion between the meltblowing layers and the yarns are not unduly affected. The calendering rolls can be heated to a degree below the melting / softening points of the various composite components, or they can be at room temperature or cooled.

Such elastic composite materials have a particular effectiveness for use in personal care products to provide elastic attributes to such products. Such elastic composite materials can provide a superior spread in either machine direction or cross machine direction than a laminate with coatings applied to one or both surfaces of an elastic layer, and can also provide a softer feel.

Such elastic composite material may be useful for providing elastic waist, leg gasket / cuff, stretchable ear, stretchable outer jacket or side panel applications. More particularly, the elastic composite material can be beneficially incorporated into a personal care article adjacent to an opening for a part of the body. Although limited is not intended, Figure 5 is presented to illustrate the various components of a personal care product, such as a diaper that can take advantage of such elastic materials. Other examples of personal care products that can incorporate such materials are the training underpants (such as side panel materials) and women's care products. By way of illustration only, the training underpants suitable for use with the present invention and the various materials and methods for constructing the training underpants are described in the patent application of the Patent Cooperation Treaty WO 00/37009 published on 29 June 2000 by A. Fletcher and others; Patents of the United States of America numbers 4,940,464 issued July 10, 1990 to Van Gompel et al .; 5,766,389 issued on June 16, 1998 to Brandon and others; and 6,645,190 granted on November 11, 2003 to Olson et al., which are hereby incorporated by reference in their entirety.

With reference to Figure 5, disposable diaper 250 generally defines a front waist section 255, a back waist section 260, and an intermediate section 265 which interconnect the front and back waist sections. The front and rear waist sections 255 and 260 include the general parts of the diaper which are constructed to extend essentially over the front and back abdominal regions of the wearer, respectively during use. The intermediate section 265 of the diaper includes the general part of the diaper that is constructed to extend through the crotch region of the wearer between the legs. Thus, the intermediate section 265 is an area where repeated repeated liquid emergences typically occur in the diaper.

The diaper 250 includes, without limitation, an outer cover or a bottom sheet 270, a liquid-permeable body side liner, or top sheet 275 placed in a front relationship with the bottom sheet 270, and an absorbent core body, or liquid retention structure 280, such as an absorbent pad, which is located between the lower sheet 270 and the upper sheet 275. The lower sheet 270 defines a length, or a longitudinal direction 286, and a width, or a lateral direction 285 which, in the illustrated embodiment, matches the length and width of the diaper 250. The liquid retention structure 280 generally has a length and width that are less than the length and width of the bottom sheet 270, respectively. Thus, the marginal portions of the honeycomb 250, such as the marginal sections of the lower sheet 270 can extend beyond the terminal edges of the liquid retaining structure 280. In the illustrated embodiments, the lower sheet 270 extends outwardly. beyond the terminal margin edges of the liquid retention structure 280 to form the side margins and end margins of the diaper 250. The topsheet 275 is generally coextensive with the bottom sheet 270 but may optionally cover an area which it is much larger or smaller than the area of the lower sheet 270 as desired.

To provide an improved notch and help reduce filtration of body exudates from diaper 250, diaper side margins and end margins may be elasticized with suitable elastic members, as explained below. For example, as representatively illustrated in Figure 5, the diaper 250 may include the leg elastics 290, which are constructed to operably tension the lateral margins of the diaper 250 to provide the elasticized leg bands which can fit closely around the leg. User's legs to reduce filtering and provide improved comfort and appearance. The waist elastics 295 are employed to elasticize the end margins of the diaper 250 to provide the elasticated waistbands. The waist elastics 295 are configured to provide a comfortable and resilient narrow notch around the wearer's waist.

The elastic composite materials of the structure of the invention and the methods are suitable for use as the leg elastics 290 and the waist elastics 295. Examples of such materials are the composite sheets which either comprise or are adhered to the bottom sheet , such as the elastic constriction forces that are imparted to the bottom sheet 270.

As is known, fastening means, such as hook and loop fasteners, can be employed to secure the diaper 250 on a wearer. Alternatively, other fastening means, such as buttons, pins, fasteners, adhesive tape fasteners, cohesives, cloth fasteners and curls, or the like can be employed. In the illustrated embodiment, the diaper 250 includes a pair of side panels 300 (or ears) to which the fasteners 302, indicated as the hook part of a hook and loop fastener are attached. Generally, the side panels 300 are attached to the side edges of the diaper in one of the waist regions 255 and 260 and extend laterally outwardly therefrom. The side panels 300 may be elastised or otherwise made elastomeric by the use of an elastic composite material made of the structure of the invention. Examples of the absorbent articles including the elastized side panels and the selectively shaped fastener appendages are described in the patent application of the Patent Cooperation Treaty No. WO 95/16425 issued to Roessler; Patents of the United States of America numbers 5,399,219 issued to Roessler and others; 5,540,795 granted to Fries and 5,595,618 granted to Fries, each of which is hereby incorporated by reference in its entirety.

The diaper 250 can also include an emergence management layer 305, located between the topsheet 275 and the liquid retention structure 280, to quickly accept fluid exudates and distribute fluid exudates to the liquid retention structure 280 within the diaper 250. The diaper 250 may further include a ventilation layer (not shown), also called a spacer, or a spacer layer, located between the liquid retaining structure 280 and the lower sheet 270 to insulate the lower sheet 270 of the liquid retention structure 280 to reduce wetting of the garment on the outer surface of a breathable outer cover or on the lower sheet 270. Examples of suitable emergence handling layers 305 are described in the patents of the United States of America number 5,486,166 granted to Bishop and 5,490,846 granted to Ellis.

As representatively illustrated in Figure 5, the disposable diaper 250 may also include a pair of containment flaps 310 which are configured to provide a barrier to the lateral flow of exudates from the body. The containment flaps 310 may be located along the laterally opposite side edges of the diaper adjacent the side edges of the liquid retaining structure 280. Each containment flap 310 typically defines a non-fastened edge which is configured to maintaining a perpendicular and vertical configuration in at least the intermediate section 265 of the diaper 250 to form a seal against the wearer's body. The containment fins 310 may extend longitudinally along the entire length of the liquid retention structure 280 or may only extend partially along the length of the liquid retention structure. When the containment flaps 310 are shorter in length than the liquid retention structure 280, said containment flaps 310 can be selectively placed anywhere along the lateral edges of the diaper 250 of the intermediate section 265. Such fins containment 310 are generally well known to those skilled in the art. For example, suitable constructions and arrangements for containment fins 310 are described in U.S. Patent No. 4,704,116 issued to K. Enloe.

The diaper 250 can be in various suitable shapes. For example, the diaper may have a global rectangular shape, a T-shape or an approximately hourglass shape. In the embodiment shown, the diaper 250 has a generally I-shape. Other suitable components which may be incorporated into the absorbent articles of the present invention may include waist flaps and the like which are generally known to those skilled in the art. Examples of diaper configurations suitable for use in connection with the present invention which include other components suitable for use in diapers are described in U.S. Patent Nos. 4,798,603 to Meyer et al .; 5,176,668 granted to Bernardin; 5,176,672 issued to Bruemmer and others; 5,192,606 granted to Proxmire et al. And 5,509,915 granted to Hanson and others, all of which are hereby incorporated by reference in their entirety.

The various components of the diaper 250 are assembled together using various types of suitable fastening means, such as adhesive bonding, ultrasonic bonding, thermal bonding or combinations thereof. In the embodiment shown, for example, the top sheet 275 and the bottom sheet 270 can be assembled together and to the liquid retention structure 280 with lines of adhesive, such as a hot melt pressure sensitive adhesive. Similarly, other diaper components, such as the elastic members 290 and 295, the fastening members 302 and the emergence layer 305 can be assembled into the article using the above identified bonding mechanisms.

It should be appreciated that such elastic composite materials can similarly be used in other personal care products, protective clothing, protective covers and the like. In addition, such materials can be used in bandage materials for both human and animal bandage products. The use of such materials provides acceptable elastic performance at a lower manufacturing cost.

These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which are more particularly set forth in the appended claims. In addition, it should be understood that the aspects of the various incorporations can be exchanged in whole or in part.

In addition, those with ordinary skill in the art will appreciate that the foregoing description is by way of example only and that it is not intended to limit the invention thus described in such appended claims.

Test Method Procedures Stretch Test to the top "Stretching to the top" refers to a certain proportion of the difference between the non-stretched dimension of a material that can be stretched and the maximum extended dimension that can be stretched with the application of a specified tensioning force and dividing that difference by the not extended dimension of the material that can be stretched. If the stretch to the top is expressed in percent, this ratio is multiplied by 100. For example, a material that can be stretched having a non-extended length of 12.7 centimeters and a maximum extended length of 25.4 centimeters with the application of a force of 750 grams has a stretch to the top (to 750 grams) of 100 percent. Stretching to the stop can be referred to as "maximum non-destructive elongation". Unless otherwise specified, the stretch values up to the top are reported here at a load of 750 grams. In the elongation or stretch test to the top, a sample of 7.62 centimeters by 17.78 centimeters, with the longest dimension being the direction of the machine, the transverse direction, or any direction between these, is placed in the jaws of a Sintech machine used a separation of 5 centimeters between the jaws. The sample is then pulled to a top load of 750 grams with a crosshead speed of about 50.8 centimeters per minute. For the stretchable material of this invention, it is desirable that it demonstrate a stretch value up to the stop between about 30-400 percent, alternatively between about 50 and 300 percent, even in an additional alternative of between about 80 -250 percent. The stretch test up to the stop is made in the direction of extension (stretch). Depending on the material that is being used, a higher applied force may be appropriate. For example, for an elastic composite material the applied force of 750 grams by 3 inches in width in the transverse direction is typically appropriate; however, for certain laminates, particularly the higher basis weight laminates, an applied force of between 750 and 2,000 grams per 3 inches wide in the transverse direction may be appropriate.

Roll Locking Test Method (for peel strength between layers of laminated layers outside a roll To perform a roll block test, a roll of approximately 50 inches of outer diameter composite material should be cut along the transverse or cross direction from the top of a roll to the core with a utility knife. , using three sections of material from the top, the core and the midpoint of the radius as samples. Each sample can be approximately 18 inches by 24 inches and can contain approximately 30 undisturbed composite tents, for example. From each of these examples, cut 8 specimens 8 inches wide by 7 inches long, with 7 inches being in the machine direction. Each specimen must contain two layers of the composite material (with each composite material including an array of continuous filaments placed between two elastic melt blown layers). Load the upper melt blown layer into one end of the specimen inside the upper jaw of the tension test unit (Sintech) while loading the lower melt blown layer of the specimen from the same end of the specimen, as was used for the upper melt blown layer, inside the lower jaw of the Sintech unit. Using the method generally described below, employ a Sintech tension tester (manufactured by MTS Systems Corporation, Model Synergie 200) to measure the average force along the length of the machine direction of the material required to separate the two layers, at an angle of 180 degrees at a voltage tension rate of 300 millimeters per minute. Test all specimens in the machine's direction.

Essentially, the test measures the force required to separate two full layers of elastic composite material from each other (simulating the unwinding of the composite material from the supply roll). It is considered that such a force will be representative of the force necessary to pull a layer of the material wound out of the roll.

In the performance of a test, the individual layers of the composite material (which is a sample of the elastic composite material and another) are manually separated by a distance of approximately 2-3 inches to give at least 4 inches of working direction, or separation length. A stratum of the specimen from the same end of the specimen is grasped in each jaw of the tension tester and the specimen is then subjected to a constant rate of extension. The sample edges are desirably cut clean and parallel. Desirably, the Sintech TestWorks software can be used to acquire data for the system. The handles include the 1-inch by 4-inch jaw faces, where the 4-inch dimension is the width of the jaw. The tests are carried out in ambient conditions of standard laboratory atmosphere. A sample of the test should measure from about 3-4 inches in the transverse direction and at least 6 inches in the machine direction. An appropriate load cell should be chosen so that the peak load value will fall between 10 and 90% of the full scale load, 25 pounds or less. Desirably a 5-pound load cell is used. Desirably, where possible, the measurement should be started at around 16 millimeters and completed to about 170 millimeters in length. The measurement length should be set to around 2 inches (distance between the jaws).

Claims (20)

R E I V I N D I C A C I O N S

1. An elastic composite material comprising: a first layer blown with elastic fusion; an array of continuous filament yarns deposited on the first blown layer with elastic fusion; Y a second blow layer with elastic fusion on the continuous filament yarns opposite to the first blown layer with elastic fusion; wherein the first blown layer with elastic fusion and / or the arrangement of continuous filament yarns comprises an elastic polyolefin-based polymer having a degree of crystallinity of between about 3% and about 40%; Y The elastic composite material is not attached and stretched.

2. The elastic composite material as claimed in clause 1, characterized in that the elastic polyolefin-based polymer has a melt flow rate of between about 10 and about 600 grams per 10 minutes.

3. The elastic composite material as claimed in clause 1, characterized in that the elastic polyolefin-based polymer has a melting / softening point of between about 40 and about 160 degrees centigrade.

4. The elastic composite material as claimed in clause 1, characterized in that the elastic polyolefin-based polymer has a density of from about 0.8 to about 0.95 grams per cubic centimeter.

5. The elastic composite material as claimed in clause 1, characterized in that the elastic polyolefin-based polymer comprises at least one of the group consisting of polyethylene, polypropylene, butene or octet homo- or copolymers, ethylene methacrylate, ethylene vinyl acetate and copolymers of butyl acrylate.

6. The elastic composite material as claimed in clause 1, characterized in that the first elastic meltblown layer comprises at least two layers, with a first layer comprising a melt blown polymer based on elastic polyolefin having a degree of crystallinity between about 3% and about 40% and a second layer comprising a melt blown polymer based on styrenic block copolymer.

7. The elastic composite material as claimed in clause 1, characterized in that it further comprises an adhesive demonstrating a relatively short open time deposited between the array of continuous filament yarns and each of the first and second elastic melt blown layers.

8. The elastic composite material as claimed in clause 1, characterized in that the first and second elastic meltblown layers each comprise a melt blown polymer based on elastic polyolefin having a degree of crystallinity of between about 3% and around 40%.

9. The elastic composite material as claimed in clause 1, characterized in that the elastic composite material is incorporated into a personal care article adjacent to an opening for a part of the body, without covering layers covering the elastic composite material.

10. A method for producing an elastic composite material, comprising: providing a first blown layer with elastic fusion; depositing an array of undrawn continuous filament yarns on the first blown layer with elastic fusion; Y depositing a second blown layer with elastic fusion on the continuous filament yarns opposite the first blown layer with elastic fusion.

11. The method as claimed in clause 10, characterized in that at least one of the first and second elastic meltblown layers comprises a meltblown polymer based on elastic polyolefin having a degree of crystallinity of from about 3% to around 40%.

12. The method as claimed in clause 10, characterized in that the continuous filament yarns comprise a melt blown polymer based on elastic polyolefin having a degree of crystallinity of from about 3% to about 40%.

13. The method as claimed in clause 10, characterized in that it comprises depositing the second blown layer with elastic fusion and an aggregate of up to about 34 grams per square meter.

14. The method as claimed in clause 10, characterized in that it comprises calendering the elastic composite material.

15. The method as claimed in clause 10, characterized in that the method does not include calendering the elastic composite material.

16. The method as claimed in clause 10, characterized in that it also comprises winding the elastic composite material on a roll.

17. The method as claimed in clause 10, characterized in that it further comprises extruding the arrangement of undrawn continuous filament yarns on the first blown layer with elastic fusion.

18. The method as claimed in clause 10, characterized in that it comprises depositing a plurality of filaments of pre-formed continuous filaments on the first blown layer with elastic fusion.

19. The method as claimed in clause 10, characterized in that it comprises extruding at least one of the first and second elastic meltblown layers.

20. The method as claimed in clause 10, characterized in that at least one of the first and second elastic meltblown layers is preformed. SUMMARY An elastic composite material that does not require coating materials. The elastic composite material includes a blown first layer with elastic fusion, an arrangement of continuous filament yarns deposited on the first blown layer with elastic fusion, and a second blown layer with elastic fusion deposited on the continuous filament yarns opposite the first layer blown with elastic fusion. One or both of the meltblown layers and / or the continuous filament yarns may include a melt blown polymer based on elastic polyolefin having a degree of crystallinity of between about 3% and about 40%. A method for making the elastic composite material is also included.