MXPA01003274A - Nonwoven web and film laminate with improved tear strength and method of making the same - Google Patents

Abstract

There is disclosed a nonwoven web/film laminate for use as a fabric in personal care products. The laminate is formed of at least two layers in an SF formation. The spunbond (S) layer of the laminate is formed of preferably metallocene catalyzed polypropylene. The film (F) layer is formed of a polyolefin which may be metallocene-catalyzed.

Description

LAMINATE OF NON-WOVEN FABRIC AND MOVIE WITH RESISTANCE TO IMPROVED RIPPING AND METHOD TO DO THE SAME Field of the Invention The present invention relates to non-woven fabric laminates and laminated films with improved strength. More particularly, the present invention relates to laminates for use in disposable clothing and personal care products with improved tear resistance, and to a method for manufacturing such laminates.

Background of the Invention The industry has long recognized the benefits of combining the barrier properties of films and fabric-like attributes of non-woven fabrics for various medical, personal and commercial care applications. In addition, such film / fabric laminates can also exhibit certain levels of elasticity, and when a narrow packed microporous film is incorporated, ability to breathe. Therefore, the laminates have been produced using both nonwoven and film materials.

The lamination of films has been used to create materials that are both waterproof and somewhat similar to the fabric in appearance and texture. Uses of such laminates include exterior covers for personal care products such as diapers, training underpants, incontinence garments, and feminine hygiene products. In this regard, reference may be made to co-assigned United States of America Patent No. 4,818,600 dated April 4, 1989 and United States of America Patent No. 4,725,473 dated February 16, 1988. In addition, such materials are particularly suitable for use in protective outerwear such as sets covers all, and surgical clothing and covers. See in this aspect the co-assigned patent of the United States of America No. 4,379,102 dated April 5, 1983.

A primary purpose of the film in such laminations is to provide barrier properties. There is also a need for such laminates to be able to breathe in order to have the ability to transmit moisture vapor. The laundry made from laminates of these microporous films with a capacity to breathe is more comfortable to use by reducing the concentration of moisture vapor and the consequent hydration of the skin beneath the article of clothing.

Despite exhibiting many positive attributes, when they are inappropriately used or when exposed to particularly high stress conditions, laminates sometimes tear. In an attempt to create a non-woven laminate with improved barrier properties, improved strength and elastic attributes, but at low costs, laminates have been developed in which the size of the fabric fiber has been reduced and the weight distribution Molecular polymer has been narrowed (since it affects the polymer's mechanical properties). For example, it has been suggested that propylene polymers having a high melt flow rate and a narrow molecular weight distribution can be used to produce fibers for fabrics and non-woven fabrics having superior barrier properties, tensile strength and smoothness. For example, U.S. Patent No. 5,529,850 issued to Morini et al. Describes the preparation of crystalline polypropylene polymers having narrow molecular weight distribution, through the use of specific di-or polyesters as external electron donors. or internal in polymerization reactions that accompany catalyst component, such as an active magnesium halide and a titanium compound and alkyl compounds.

US Patents Nos. 5,726,103 and 5,763,080 issued to Stahl et al. Describe fibers and fabrics incorporating low melting propylene polymers in order to achieve a relatively impermeable cloth. strong and impervious to fluid. In particular, the Stahl patents describe the propylene homopolymers and the copolymers formed by metallocene catalyst systems. Such polymers generally exhibit lower melting behavior than catalyzed propylene polymers without metallocene. Stahl indicates that this low casting behavior is to be used in the manufacture of fibers and cloth that depend on the casting behavior under or on the melting point differential between two fabrics to achieve bonding. Such fibers may include sheath and core, with lock or chenille. Stahl indicates that fabrics such as non-wovens blown with fusion or spun-bonded, when combined into fabrics linked by spinning / blown with melting / linked by spinning (SMS) can show binding at low temperatures, and in particular, they allow to make a high casting fiber in a low melting fiber and blown with fusion in a linked by spinning. In the possible examples of the Stahl patents, Stahl indicates that the total strength of the fabric samples using metallocene catalyzed polypropylene in the spin-bonded layers can be as high as controls (which are unbound fabrics linked by spinning / blown with fusion). In possible additional examples using an "S" layer of metallocene catalyzed homopolymer polypropylene and a commercially available "M" polypropylene layer of 1100 mfr, the possible fabric may have improved filtration and barrier properties without loss of strength of laminated fabric when compared to the control. Each of these patents does not provide a better than expected resistance to tearing in a nonwoven film laminate.

The patent of the United States of America No. ,723,217 issued to Stahl et al. Describes the polyolefin fibers and their fabrics. This Stahl patent describes the fibers made of isotactic poly-alpha-olefin grade reactor wherein the polypropylene is produced by single site catalysts. Stahl claims that the polypropylene fibers produced will generally be more resistant or have a higher toughness than conventional polymer when pulled to a fine diameter. Stahl also states that spinning or meltblown fabric containing the fiber may gain extra strength but does not allude to any method for creating a breathable film laminate with increased tear strength.

The patent of the United States of America No. ,612,123 issued to Gessner et al. Describes an increased distribution of a polyolefin product. In particular this patent discloses that improved melt bonded productivity is achieved by the use of polyolefin resins having key molecular weight distributions and rheological property parameters within predetermined ranges. Such polyolefin filaments and the single layer yarn bonded fabric prepared by the process exhibited high tenacity and tear property values. This patent also fails to allude to a method for increasing the tearing properties of a film laminate capable of breathing.

U.S. Patent No. 5,464,688 issued to Timmons et al. Describes non-woven fabric laminates with improved barrier properties. Such fabrics are formed with commercially acceptable polymer with reduced molecular weight distribution in the meltblown layer of a spunbond / meltblown / spunbond bond.

Although the metallocene catalyzed polypropylene has hitherto been used in laminates, specifically as part of the bonded bonded laminates and the bonded laminates, the structural components, the physical attributes and the bonding processes of these laminates are markedly different from those of the laminates. film laminates with capacity to breathe. In addition, the tear measurement tests, such as tension to grip / peak energy for joint with narrowing (NBL) and tightly bound laminates (SBL), as well as a single yarn bonded layer shows a high peak energy value (in the machine direction) for the spinning of Ziegler-Natta catalyzed polypropylene that for the catalyzed spinning of metallocene in these laminates . Therefore, one can not expect that spinning linkage with narrow molecular weight distribution will be able to significantly increase tear resistance in a breathable nonwoven fabric / film laminate.

Therefore, despite improvements in the non-woven laminate area, there is a need for a non-woven / breathable film laminate which demonstrates an increase in tear strength without the addition of significant cost. . further, there is a need for a method for producing such a laminate compound which can be made in line at high speeds and over a short time lapse. Finally, there is a need for personal care products and other clothes which use such laminates in their composite constructions. It is to the provision of such a compound and method to which the present invention is directed.

Synthesis It is an object of the present invention to provide a film / nonwoven fabric laminate which exhibits significant tear resistance attributes.

It is still a further object to provide a film / nonwoven laminate incorporating the features described above which uses relatively relatively inexpensive materials to increase the strength properties.

It is still a further object to provide an in-line process for preparing a film / nonwoven laminate which allows for increased tear resistance to the finished laminate.

A specific object is to provide a material that has many of the previously identified attributes which can be advantageously used in personal care products.

The present invention relates to a nonwoven fabric / film laminate comprising at least one nonwoven fabric layer having a narrow molecular weight distribution and a film.

In one embodiment of the present invention, the film is a narrow microporous film that includes an elastomeric resin and a film filler.

The present invention is also directed to a process for producing a laminate including at least one layer of non-woven fabric having a narrow molecular weight distribution and a film including the steps of forming a non-woven fabric of a catalysed polypropylene of metallocene and bond a layer of film to the newly formed nonwoven fabric layer within 1 to 30 seconds of formation of the non-woven fabric layer.

Brief Description of the Drawings Figure 1 is a cross-sectional view of a material incorporating the features of the present invention.

Figure 2 is a schematic side elevational view illustrating a manner in which the material of the present invention can be prepared.

Figure 3 is a top plan view of an exemplary personal care article, in this case a diaper, which may use a laminate according to the present invention.

Detailed description of the invention Definitions As used herein the term "polymer" generally includes but is not limited to, homopolymers, copolymers, such as, for example, block, graft, random and alternating copolymers, terpolymers, et cetera and mixtures and modifications thereof . In addition, unless specifically limited, the term "polymer" should include all possible geometric configurations of the molecule.

These configurations include, but are not limited to, isotactic, syndiotactic and random symmetries.

As used herein the term "spunbonded fibers" refers to fibers of small diameter which are formed by extruding molten thermoplastic material as filaments into a plurality of usually thin circular capillary vessels, of a spinner organ having the diameter of extruded filaments being rapidly reduced as, for example, in U.S. Patent No. 4,340,563 issued to Appel et al., and U.S. Patent No. 3,692,618 issued to Dorschner and others, U.S. Patent No. 3,802,817 issued to Matsuki et al., U.S. Patent Nos. 3,338,992 and 3,341,394 issued to Kinney, U.S. Patent No. 3,502,763 issued to Hartman. , and U.S. Patent No. 3,542,615 issued to Dobo et al. Spunbonded fibers are generally not sticky when deposited on a collecting surface. Spunbonded fibers are generally continuous and have average diameters (of a sample of at least 10) larger than 7 microns, more particularly, between about 10 and 20 microns.

As used herein, the term "meltblown fibers" means fibers formed by extruding a molten thermoplastic material through a plurality of matrix capillary cups., usually circular, thin as melted yarns or filaments in gas streams (eg air), usually hot at high speed converging which attenuate the filaments of molten thermoplastic material to reduce its diameter, which may be of microfiber diameter. Then, the meltblown fibers are transported by the high velocity gas stream and are deposited on a collecting surface to form a fabric of meltblown fibers dispersed randomly. Such a process is described, for example, in United States of America Patent No. 3,849,241 issued to Butin et al. Meltblown fibers are microfibers which may be continuous or discontinuous, are generally smaller at 10 microns in average diameter, and are generally sticky when deposited on a collecting surface.

As used herein, the term "multi-layered laminate" means a laminate wherein some of the layers are spin-bonded and some are meltblown such as spin-linked / meltblown / spunbonded (SMS) laminate and others, such as those described in United States of America No. 4,041,203 to Brock et al., United States of America No. 5,169,706 to Collier et al., United States of America No. 5,145,727 granted to Potts et al., United States of America Patent No. 5,178,931 issued to Perkins et al. and United States of America Patent No. 5,188,885 to Timmons and others. Such lamination can be done by subsequently depositing it first on a forming web that moves a layer of spin-linked fabric, then a layer of meltblown fabric and finally another spin-linked layer and then attaching the laminate in the manner described below. . Such fabrics usually have a basis weight of about 0.1 to 12 ounces per square yard (3.4 to 400 grams per square meter), or more particularly about 0.75 to about 3 ounces per square yard. The multi-layer laminates may also have several numbers of melt-blown layers or multiple spin-bonded layers in many different configurations and may include other materials such as films (F) or coform materials, for example spunbonded / meltblown / meltblown / spunbonded SMMS, spunbonded / meltblown with SM fusion, spunbonded / bonded / bonded by SFS yarn, etcetera.

As used herein, the term "personal care product" means diapers, training underpants, absorbent pants, adult incontinence products, and feminine hygiene products.

As used herein the term "thermal spot bonding" involves passing a fabric or fabric of fibers to be joined between a heated calendered roll and an anvil roll. The calendered 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 roll is usually flat. As a result, several patterns have been developed for the calendered rolls for functional as well as aesthetic reasons. An example of a pattern has points and is the Hansen pattern & Pennings or "H &P" with about 30% area joined with about 200 joints per square inch as taught in U.S. Patent No. 3,855,046 issued to Hansen & Pennings. The H &P pattern has needle point or square dot areas where each needle has a side dimension of 0.038 inches (0.965 millimeters), a gap of 0.070 inches (1,778 millimeters) between needles, and a bond depth of 0.023 inches (0.584 millimeters). The resulting pattern has a binding area of about 29.5%. Another typical point binding pattern is the Hansen & Extended Pennings or "EHP" which produces a 15% bond area with a square needle that has a side dimension of 0.037 inches (0.94 millimeters), a 0.097 inch (2.464 millimeters) needle gap and a 0.039 inch depth (0.991 millimeters). Another typical point union pattern described as "714" has square needle joining areas where each needle has a side dimension of 0.023 inches, a gap of 0.062 inches (1,575 millimeters) between needles, and a bond depth of 0.033 inches (0.838 millimeters). The resulting pattern has a binding area of about 15%. Still another pattern such as the Star-C pattern which has a bond area of about 16.9%. The Star-C pattern has a transverse direction bar or "corduroy" design interrupted by shooting stars. Other common patterns include a diamond pattern with slightly shifted diamonds and repeating with about a 16% bond area and a wire weave pattern that looks like the name suggests, for example similar to a window screen, with around 19% of joint area. Typically, the percentage of bond area varies from about 10% to about 30% of the area of the fabric laminated fabric. As is well known in the art, precision bonding maintains the laminate layers together as well as imparting integrity to each individual layer by bonding filaments and / or fibers within each layer.

As used herein, the term "ultrasonic bonding" means a process effected, for example, by passing the fabric between a sonic horn and an anvil roll as illustrated in U.S. Pat. No. 4,374,888 awarded to Bornslaeger.

As used herein the term "composite elastic material" refers to an elastic material which may be a multi-component material or a multi-layer material in which a layer is elastic. These materials can be, for example, "narrow-bonded" laminates (SBL) and "tight-bonded" laminates (NBL). Conventionally, "tapered" refers to an elastic member that is joined to another member while the elastic member extends at least about 25% more than its relaxed length. "Narrow bonded laminate" refers to a composite material having at least two layers in which one layer which is a unible layer and the other layer is an elastic layer. The layers are joined together when the elastic layer is in an extended condition so that when the layers are relaxed, the unible layer is collected. Such elastic composite material of multiple layers can be narrowed to an extent that the non-elastic material collected between the joined locations allows the elastic material to elongate. One type of bonded bonded laminate is described, for example, in U.S. Patent No. 4,720,415 issued to Vanderielen et al., In which multiple layers of the same polymer produced are used by multiple banks of extruders. Other composite elastic materials are disclosed in U.S. Patent No. 4,789,699 issued to Kieffer et al., U.S. Patent No. 4,781,966 issued to Taylor and U.S. Patent Nos. 4,657,802. and 4,652,487 granted to Morman and No. 4,655,760 granted to Morman and others.

Conventionally, "tapering" refers to an elastic member that is attached to a non-elastic member while the non-elastic member is extended under conditions that reduce its width or narrowing. "Narrow-bonded laminate" refers to a composite material having at least two layers in which one layer is a non-elastic, tapered layer and the other layer is an elastic layer. The layers are joined together when the non-elastic layer is in an extended condition. Examples of bonded laminates are such as those described in US Pat. Nos. 5,226,992, 4,981,747, 4,965,122 and 5,336,545 issued to Morman.

As used herein, the term "compaction roller" means a set of rollers above and below the fabric for compacting the fabric as a way of treating a poorly produced microfiber, particularly a spin-linked fabric, in order to give it a sufficient integrity for further processing, but not the relatively strong bonding of secondary bonding processes such as bonding through air, thermal bonding and ultrasonic bonding. The compaction rollers slightly squeeze the fabric in order to increase its self-adhesion and therefore its integrity. As an alternative to the use of a compaction roller, a pressurized target air stream (hot air blade) can be used to compact a newly formed fabric. As used herein, the term "hot air knife" or HAK means a process of pre-bonding to a newly produced microfiber, particularly a spin-linked fabric, in order to give sufficient integrity, for example increase the stiffness of the fabric , for further processing, but without meaning to say the relatively resistant bonding of secondary bonding processes such as the bonding through air, the thermal bonding and the ultrasonic bonding. A hot air knife is a device which focuses a stream of hot air at a high flow rate, generally from about 1,000 to about 10,000 feet per minute (fpm) (305 to 3050 meters per minute), or more particularly from about 3,000 to 5,000 feet per minute (915 to 1525 meters per minute) directed to the web not woven immediately after its formation. The air temperature is usually in the range of the melting point of at least one of the polymers used in the fabric, generally between about 200 ° F and 550 ° F (93 ° C and 290 ° C) for the thermoplastic polymers commonly used in spinning. The control of air temperature, speed, pressure, volume and other factors help to avoid tissue damage while increasing its integrity. The focused air stream of the hot air blade is arranged and directed by at least one groove of about 1/8 to 1 inch (3 to 25 millimeters) wide, particularly about 3/8 inch (9.4 millimeters) ), which serve as the outlet of the hot air to the fabric, with the groove running in a direction substantially transverse to the machine over substantially the full width of the fabric. In other embodiments, there may be a plurality of grooves arranged together with one another or separated by a light space. The at least one of the slots is usually, although not essentially, continuous, and may be composed of, for example, closely spaced orifices. The hot air blade has a plenum to distribute and contain the hot air before it leaves the slot. The plenum pressure of the hot air blade is usually between about 1.0 and 12.0 inches of water (2 to 22 millimeters of mercury), and the hot air blade is positioned between about 0.25 to 10 inches and more preferably at 0.75. to 3.0 inches (19 to 76 millimeters) above the forming wire. In a particular embodiment, the hot air knife of the transverse sectional area of the plenum for the transverse directional flow (for example the cross-sectional area of the plenum in the machine direction) is at least twice that of the exit area of the plenum. the total slot. Because the foraminous wire in which the spin-bonded polymer is generally formed moves at a high velocity rate, the exposure time of any particular part of the fabric to the air discharged from the hot air knife is less than one tenth of a second and generally about a hundredth of a second in contrast to the process of union through air which has a much longer time of dilation.

The hot air knife process has a large range of variability and controllability of many factors such as air temperature, velocity, pressure, volume, arrangement and size of the orifice or slot, and the distance from the plenum. of hot air knife to the fabric. The hot air blade is further described in U.S. Patent No. 5,707,468 and commonly assigned.

As used herein the term "nonwoven fabric or fabric" means a fabric having a structure of individual fibers or threads which are interlaced, but not in an identifiable manner as in a woven fabric. Fabrics with woven fabrics have been formed by many processes such as, for example, meltblowing processes, spin-linked processes, and bonded carded fabric processes. The basis weight of the non-woven fabrics is usually expressed in ounces of material per square yard (osy) or grams per square meter (gsm) and the useful fiber diameters are usually expressed in microns. (Note that to convert ounces per square yard to grams per square meter, multiply ounces per square yard by 33.91).

As used herein the term "microfibers" means small diameter fibers having an average diameter of no more than 75 microns, for example, having an average diameter of about 0.5 microns to about 50 microns, or more particularly, microfibers They can have an average diameter of around 2 microns to around 40 microns. Another commonly used expression of fiber diameter is denier, which is defined in grams per 9,000 meters of a fiber and can be calculated as fiber diameter in square microns, multiplied by the density in grams per cubic centimeter, multiplied by 0.00707 . A low denier indicates a finer fiber and a high denier indicates a heavier or thicker fiber. For example, the diameter of a polypropylene fiber given as 15 microns can be converted to denier by the square, multiplying the result by 0.89 grams per cubic centimeter and multiply by 0.00707. Therefore, a polypropylene fiber of 15 microns has a denier of about 1.42 (152 x 0.89 x 0.00707 = of 1.415). Outside the United States of America, the most common unit of measure is "tex", which is defined as grams per kilometer of fiber. The tex can be calculated as denier / 9.

As used herein, in the term "machine direction" or MD means the direction of a web in the direction in which it is produced. The term "cross machine direction" or CD means the opposite direction to the fabric, for example an address generally perpendicular to the machine direction.

For the purpose of this application the term "conventional" should refer to Ziegler-Natta catalyzed propylene homopolymers and copolymers. For an additional description of the Ziegler-Natta catalyzed reactions, one should refer to the Encyclopedia of Engineering and Science of Polymer, volume 8, page 162, published by John Wiley & Sons, Inc., 1987.

Referring to Figure 1, the nonwoven film / fabric laminate 10 of the present invention can be made of polymers which are capable of being formed into a film 15 and then attached to the non-woven fabric 20. The film can be freshly formed or preformed film. The nonwoven fabric is preferably newly formed.

Such film-forming polymers include but are not limited to extrudable thermoplastic polymers such as a polyolefin or a mixture of polyolefins. More particularly, useful polyolefins include polypropylene and polyethylene. Other useful polymers include those described in U.S. Patent No. 4,777,073 issued to Sheth, assigned to Exxon Chemical Patents Inc., such as copolymer of polypropylene and low density polyethylene or linear low density polyethylene. Additional polymers useful in the present invention include flexible polyolefins. As used herein, the term "flexible polyolefin" refers to polyolefin materials containing propylene-based polymer with controlled regions of atactic polypropylene units to achieve a desired crystallinity as described in the co-assigned United States patent. of America No. 5, 910,136 titled "Polymeric Microporous Films Oriented with Flexible Polyolefins and Methods for Making Them" given to Hetzler and Jacobs; the complete content of which is incorporated herein by reference in its entirety. A further description of such flexible polyolefins can be found in U.S. Patent No. 5,723,546 issued to Sustic and assigned to Rexene Corporation.

Other polymers useful for film formation of the present invention include elastomeric thermoplastic polymers. Such polymers include those made from block copolymers such as polyurethanes, copolyether esters, polyamide, polyether block copolymers, ethylene vinyl acetates (EVA), block copolymers having the general formula ABA 'or AB as copli (styrene / ethylene-butylene), styrene-poly (ethylene-propylene) -styrene, styrene-poly (ethylene-butylene) -styrene, (polystyrene / poly (ethylene-butylene) / polystyrene, poly (styrene / ethylene-butylene / styrene) and the like Specifically, elastomeric thermoplastic polymers include: polyester elastomeric materials such as, for example, those available under the HYTREL® trademark designation of EI du Pont de Nemours and Company: polyester block amide copolymers such as, for example, those available in various grades under the PEBAX® trademark designation from ELF Atochem Inc. of Glen Rock, New Jersey; it is polyurethane elastomeric such as, for example, those available under the trademark ESTAÑE® de B.F. Goodrich & Co. or MORTHANE® of Morton Thiokol Corporation.

Elastomeric polymers have been used in the past for many applications but are somewhat limited by their intrinsic properties. These materials have recently been joined by a new class of polymers which demonstrate attributes of elasticity, ability to breathe and high barrier when incorporated into the film. The new class of polymers is referred to as single site catalyzed polymers such as the "metallocene" polymers produced according to the processes of a metallocene.

Such metallocene polymers are available from Exxon Chemical Company of Baytown, Texas under the brand name EXXPOL® for polymers based on polypropylene and EXACT® for polymers based on polyethylene. Dow Chemical Company of Midland, Michigan has polymers commercially available under the name of ENGAGE®. More specifically, the metallocene film-forming polymers can be selected from copolymers of ethylene and 1-butene, the copolymers of ethylene and 1-hexene, the copolymers of ethylene and 1-ketene and combinations thereof.

The laminated film layer 15 may be a multilayer film which may include a core layer 16, or a "B" layer, and one or more skin layers of 17, or "A" layers on each side of the layer core. Any of the polymers described above are suitable for use as a core layer of a multilayer film.

The skin layer may typically include extrudable thermoplastic polymers and / or additives which provide specialized properties to the film 15. Therefore, the skin layer can be made of polymers which provide such properties as antimicrobial activity, vapor transmission, water, antiblocking and / or adhesion properties. The polymers are therefore chosen for their particular desired attributes. Examples of possible polymers that can be used alone or in combination include homopolymers, copolymers and blends of polyolefins as well as ethylene vinyl acetate (EVA), ethyl ethylene acrylate (EEA), acrylic acid ethylene (EAA), ethylene methyl acrylate (EMA), ethylene butyl acrylate (EBA), polyester and (PET), nylon (PA), ethylene vinyl alcohol (EVOH), polystyrene (PS), polyurethane (PU), and olefinic thermoplastic elastomers which are multi-step reaction products in which a random amorphous ethylene propylene copolymer is molecularly dispersed in a polyethylene monomer / polypropylene monomer predominantly semicrystalline continuous matrix.

Suitable polymers for the "A" layer are commercially available under the brand name of "Catalloy" from Himot Chemical Company of Wilmington., Delaware, and polypropylene. The specific commercial examples are Catalloy, KS 357P, KS-084P and KS-057P. Other suitable polymers include polymers which are orfous / semicrystalline or heterophasic in performance. Such polymers are described in European patent application No. EP 0444671 A3 (based on application number 91103014.6), European patent application No. EP 0472946 A2 (based on application number 91112955.9), European patent application EP No. 0400333 A2 (based on the application number 90810851.5), the patent of the United States of America No. 5,302,454 and the patent of the United States of America No. 5,368,327. For a more detailed description of the films having skin and core layers see PCT WO 96/19346 granted to McCormack and others assigned to the common assignee which is hereby incorporated by reference in its entirety.

Films can be made of materials if: ability to breathe c with ability to breathe. Some: - = films are hecñss able to breathe by adding filler particles developing micropores to the film during the process of film formation.

As used herein, a "micropore developing filler" means that it includes particles and other forms of materials which can be added to the polymer and which chemically will not interfere with or adversely affect the extruded film made of the polymer but are capable of being uniformly dispersed. through the movie. Generally, micropore developing fillers may be in the form of a particle and may usually have some spherical shape with average particle sizes in the range of about 0.5 to about 8 microns. The film will usually contain at least about 30% filler developing micropore based on the total weight of the film layer. Both fillers developing inorganic and organic micropore are contemplated to be within the scope of the present invention as long as they do not interfere with the film forming process, the ability to breathe of the resulting film or its ability to bond to the nonwoven fabric. of fibrous polyolefin.

Examples of micropore developing fillers include calcium carbonate (CaC03), various types of clay, silica (Si02), alumina, barium sulfate, sodium carbonate, talc, magnesium sulfate, titanium dioxide, zeolites, sulphate aluminum, cellulose type powders, diatomaceous earth, magnesium sulfate, magnesium carbonate, barium carbonate, kaolin, mica, carbon, calcium oxide, magnesium oxide, aluminum hydroxide, pulp powder, wood powder, derivative of cellulose, polymer particles, chitin and chitin derivatives. The microporous filling filler particles can optionally be coated with a fatty acid, such as stearic acid, or a larger chain fatty acid such as behenic acid, which can facilitate the free flow of particles (in bulk) and its ease of dispersion in the polymer binder. Fillers containing silica may also be present in an effective amount to provide anti-blocking properties.

Once the particle filled film has been formed, it is then either tapered or crushed to create trajectories through the film. Generally, to qualify as being "breathable" for the present invention, the resulting laminate should have a water vapor transmission rate (WVTR) of at least 250 grams per square meter per 24 hours as it may be. measured by the test method described below. In addition, movies can be opened. In the formation of the films, the films can be coextruded to increase the bond and alleviate the accumulation of cutting die.

The processes for forming film are generally known. The film 15 can be made of blown or cast film equipment, can be co-extruded and can be embossed if desired. Additionally, the film 15 can be tapered or oriented to pass the film through a film narrowing unit. Narrowing reduces the size of the film or thickness of the initial measurement from 1.5 to 2.0 mils to an effective final measurement of 0.5 mils or less. Generally, this narrowing can take place in the direction transverse to the machine or in the machine direction or both.

The non-woven fabric 20 as illustrated in Figure 1, in the laminate 10 containing the film of the present invention, can be formed from a number of processes including, but not limited to, meltblowing processes or of linked by spinning. Such non-woven fabrics can, for example, be bonded with narrow polypropylene yarn, bonded by folded polypropylene yarn, meltblown fabrics or elastomeric spin-bonded fabrics produced from elastomeric resins. As used herein, the term "constricted" refers to narrowing in at least one dimension by processes such as, for example, pulling or picking.

Fibers especially suitable for forming nonwoven fabric include narrow molecular weight distribution polymer fabrics such as spinning of metallocene-catalyzed polypropylene, and in particular the spunbonding of inelastic metallocene-catalyzed polypropylene sold under the designation 3854, available from Exxon Chemical Company of Baytown, Texas. The single site metallocene catalyzed polypropylenes are sold by Exxon under the brand name Achieve. In the practice of this invention, a single nonwoven fabric layer can be laminated to a film layer. An example of such is a spin-linked (S) / laminated film / (F). Alternatively, a plurality of nonwoven fabric layers may also be incorporated into the laminate according to the present invention. Examples of such materials may include, for example, spunbonding / films / spunbonding of multilayer laminates.

In the process of the present invention, as shown in FIG. 2, the filled film 15 is directed to a supply roll 21 to a film shrinking unit 30 such as a machine direction marker (MDO), which is a device commercially available from vendors such as Marshall and Williams Company and Providence, Rhode Island. Such an apparatus has a plurality of nip rolls 32 that move progressively at faster reactive speeds to the pair disposed thereto. These rollers apply a quantity of tension and therefore progressively narrow the filled film to a length of narrowing in the machine direction of the film whose film path direction is filled through the process as shown in figure 2. Narrowing rollers can be heated for better processing. Additionally, the unit may also include rollers (not shown) upstream and / or under current from the nip rollers that can be used to preheat the film before being tapered and / heat harden (or chill) after tapering.

In the narrowed length, a plurality of micropores are formed in the film. The film is then directed away from the apparatus so that the tension is removed in order to allow the tapered film to relax. A permanent lengthening of retention after the narrowed film has been allowed to relax.

Alternatively, instead of being preformed and supplied by a supply roll, the film can itself be formed in line. Such process is described in the provisional patent application of the United States of America entitled "Process for Making an Unmeasured Film Laminate of a Non-Woven Fabric Not Measured and Products Produced Therefrom" filed on September 22, 1998, the express mail number EL 154777056US and assigned to the same transferee of said request being incorporated herein by reference in its entirety.

A fibrous nonwoven fabric layer is contemporaneously formed in a conventional fibrous nonwoven fabric forming apparatus. As illustrated in Figure 2, a pair of spinning linkers 35 are used to form the nonwoven fabric layer. Alternatively, a single bank of spinning machines can be used. The essentially elongate continuous fibers are deposited on a forming wire as an unbonded fabric 19 and the unbonded fabric 19 and the unbonded fabric is then sent through a pair of bonding rollers 36 and 37 to join the fibers together. increasing the tear resistance of the resulting fabric support layer 20. One or both of the rolls are often heated to assist in bonding. Typically, one of the rollers also has a pattern so as to impart a discrete bond pattern with a predescribed bonding surface area to the fabric. An example of a bonding pattern which may be used may be the wire weave pattern. The other roller is usually an anvil roller and soft but this roller can also have a pattern if desired. During the process before joining, the spunbonded fabric can be compressed using a set of compaction rollers (not shown) or a hot air knife (not shown).

Once the filled film has been sufficiently narrowed and the non-woven fabric layer has been formed, the two layers are brought together and laminated with each other using a pair of lamination rolls 38 and 39 (thermal point attachment) or other joining means for forming a thinned stretch film laminate capable of breathing (BSTL). As with the bonding rolls, the rolling rolls can be heated. Also, at least one of the rollers may have a pattern to create a discrete bond pattern with a predescribed joint surface area for the resulting laminate. Generally, the maximum junction surface area for a given area of the surface on one side of the laminate may not exceed about 50% of the total surface area. There are a number of discrete union patterns which can be used, an example of which is the Baby Objects or Star-C pattern, generally having a junction surface area of between 15% and 30%. The time between the formation of the spin-linked fabric and the lamination of the fabric to the film is about 1 to 30 seconds. See, for example, United States of America Patent No. 4,041,203 issued to Brock et al., Which is incorporated by reference in its entirety. Once the laminate leaves the rolling rolls, it can be entangled in a roller for subsequent processing. Alternatively, the laminate can continue online for further conversion or processing.

The process shown in Figure 2 can also be used to create a three-layer woven film laminate. The only modification to the process described above is to feed a supply of a second layer of fibrous nonwoven fabric into the rolling rolls on one side of the filled film opposite the other layer of fibrous nonwoven fabric. One or both of the non-woven fabric layers can be directly formed in line as is the non-woven fabric layer 20. In any case, the second roll is fed to the rolling rolls as the film filled in the same manner is laminated. as the first layer of non-woven fabric. Such three-layer laminates are particularly useful in the applications of external workwear / industrial and medical protective clothing.

As mentioned above, non-woven fabric / film laminates can be used in a wide variety of applications which include absorbent articles for personal care such as diapers, training underpants, incontinence devices and products. for feminine hygiene such as sanitary napkins. An example article, in this case a diaper 50, is shown in Figure 3 of the drawings.

Referring to Figure 3, most such personal care absorbent articles include a liner or liquid permeable top sheet 52, with the outer cover or lower sheet 54 and an absorbent core 56 disposed between and contained by the lower sheet and the lower sheet. top sheet Items such as diapers may also include some type of fastener means such as adhesive fastening tapes 58 or a mechanical hook and curl type fasteners to hold clothing in place of the wearer. The fastening system may have narrow material to form narrowed ears for greater comfort.

The film / nonwoven laminates can be used to form various parts of the article 50 including, but not limited to, the backing sheet 54 and the top sheet 52. When using the non-woven film / fabric laminate with an outer cover, it is usually advantageous to place the non-woven side away from the wearer. Additionally, in such embodiments it may be possible to use the non-woven part of the laminate as the loop part of the hook and the loop combination.

Other uses for the filled film and the nonwoven film / fabric laminates according to the present invention include, but are not limited to protective working clothes such as surgical covers and gowns, covers, lab coats and other clothing items.

As will be explained in more detail below, an unexpected and surprising improvement of the present invention lies in its increase in the tear strength of the nonwoven film / fabric laminate as measured by the numerous test protocols. These improvements in tear resistance are transferred to the articles of manufacture using the laminates as a structural component, such as personal care articles and protective workwear. An advantage of the present invention lies in that the tear strength is improved using a fast inline process, and without the use of relatively more expensive materials.

The present invention is further described by the following examples. Such examples, however, should not be construed as limiting in any way either by the spirit or scope of the present invention.

Examples A series of materials were prepared in accordance with the processes described above including the spunbonding of conventional Ziegler-Natta catalyzed polypropylene (designated as ZN PP), and the spun bonding of metallocene-catalyzed polypropylene (designated as Met PP) as support layers. The materials used in the film / nonwoven laminate are described in the following table 1.

T B L A Example Conditions The yarn-bound material was introduced into the spin-linked extruders. For example, metallocene polypropylene 3854 from Exxon was introduced. The entry of the linkage by spinning was approximately 0.7 grams per hole per minute (GHM). The melting temperature for spinning is typically around 232 ° C (450 ° F). The positions of the hot air knife and the calendering linked by spinning were optimized for the metallocene catalyzed materials. The typical temperature of calendered spinning is about 154.4 ° C to 165.5 ° C (310 ° to 330 ° F) in the bonding rolls. The temperature of the hot air knife is usually maintained between 104.4 ° C to 115.5 ° C (220 ° to 240 ° F). The position of the machine direction indicator on the rollers was as follows: for the preheated roller 1-preheated 2, the position was at 76%, for the preheated roller 2 -lent, the position was at 98%, for the quick roller -Low roll, the position was to 29%, for the roller 1 recosido-fast roller, the position was to 100.5%, for the roll 1 annealing 2 annealed, the position was to 100.5%, for the annealed roll 2 -calendered, the position was at 101%, for the calendering-entangling roller, the position was at 94%, and for the entangled drum roller the position was a group at 100.5%. The positions are expressed in percentages of the previous roller speed.

The denier of the linked by yarn produced was 2.0 denier per filament. The film was introduced from the supply rollers and the laminate was made with calendering temperatures at 126/104 ° C (260 ° / 220 ° F). The temperature of the upper roller is the first to be mentioned.

Following the lamination of the film and the layers bound by spinning in the laminates linked by spinning / film, the following comparative tests for the materials were run, the results of which are expressed in table 2. A comparison of information for a layer simple spunbonded as well as tightly bonded are shown in Tables 3 and 4.

Test Methods Base Weight (B.W.): This test determines the unit air mass of the textile material by using a small sample of 12.7 cm x 12.7 cm (5 x 5 inches). The measurement is typically expressed in grams per square meter (gsm) or ounces per square yard (osy).

Hydrohead (Hydrostatic Head): A measure of the liquid barrier properties of a cloth is the hydro head test. The hydro head test determines the height of the water (in centimeters) that the fabric can support before a predetermined amount of liquid passes through it. The test measures a resistance of the fabric to water under static pressure. Under controlled conditions, a sample is subject to the water pressure that increases at a constant rate until dripping appears on the bottom surface of the material. The water pressure is measured at the hydrostatic head height reached after the third drip signal. The values are registered in millibarras of pressure. When melted melted material is tested, a support network is used. A cloth with a high hydro head reading indicates that it has a greater barrier to penetration of the liquid than a cloth with a low hydro head. The hydro head test is performed according to the normal federal test 191A, method 5514 using an FX-3000 head tester available from Mario Industries, Inc. PO Box 1071, Concord, North Carolina.

Test to Tear Elmendorf (Ele.): This test measures the average force required to propagate a tear starting from a slot cut in the sample being tested, when part of the sample is held in a clamp and an adjacent part is moved by the force of a pendulum in freefall in a bow. The sample size is 6.35 cm x 10.16 cm (2.5 x 4 inches) and the test can be conducted in the cross machine direction or in the machine direction. When conducting the test, one of the following brand testers should be used. The Elmendorf Digi-tear model 65-200 brand, and the 65-200 air clamps obtained from the Thwing-Albert Instrument Company, Philadelphia, Pennsylvania, or the Lorentzen and Wettre brand, model 09ED obtained from Lorentzen Wettre Canada Inc., of Fairfield, New Jersey, or the Textest FX 3700 brand (Digital Elmendorf) obtained from Schmid Corporation of Spartanburg, South Carolina.

Trap Torn Test (Trapezoidal Torn (Trap)); The "trap" or trapezoidal tear test is a stress test applicable to both non-woven and woven fabrics.

The total width of the sample is grasped between clamps, so in the primary measurements of the test the union or interlock and the strength of the individual fibers directly in the stress load, instead of the resistance to the composite structure of the fabric as a whole. The procedure is to supplement the relative ease of tearing a fabric. This is particularly useful in determining any appreciable difference in the resistance between the machine and the transverse direction of the fabric. The test measures the resistance of the fabric to the propagation of tearing under a constant rate of extension. A fabric cut on a bank is hugged along the non-parallel sides of a trapezoidal sample and is pulled, making a tear propagation in the sample perpendicular to the load. The test can be conducted in either the cross machine direction in the machine direction. When driving the trap tear test, an outer line of a trapezoid is drawn on a 3-by-6-inch (75 by 152-millimeter) sample with the longest dimension in the direction being tested, and the sample is cut off at the shape of a trapezoid. The trapezoid has a side of 4 inches (102 millimeters) and a side of 1 inch (25 millimeters) which are parallel and which are separated by 3 inches (76 millimeters). A small preliminary cut of 5/8 of an inch (15 millimeters) is made in the smallest half of the parallel sides. The sample is embraced by, for example, an Instron model TM (an extension-rate-constant tester), available from the Instron Corporation, 2500 Washington St., Canton, MA 02021, or a Thwing-Albert model INTELLECT II available from the Thwing-Albert Instrument Co. , 10960 Dutton Rd., Phila 19154, which are 3 inches (76 millimeters) long of parallel clamps. The sample is hugged along the non-parallel sides of the trapezoid so that the fabric on the longer side is loose and the fabric along the shorter taut side, and with the cut in half between the clamps. A continuous load is applied to the sample such that the tear propagates transversely to the width of the sample. It should be shown that the longest direction is the direction being tested even when the tear is perpendicular to the length of the sample. The force required to completely tear the sample is recorded in pounds with higher numbers indicating greater tear resistance. The test method used conforms to the normal test ASTM DI117-14 except that the tear load is calculated as the average of the highest peaks and the first peaks recorded instead of the highest and lowest peaks. Five samples of each sample should be tested. The information presented includes the high peak values and first. In this procedure also conforms to method 5136, of federal test method standards No. 191 published in December 1968. The difference between the ASTM procedure and the federal one is in the final calculation as the average of the lowest peaks and most tall; In the federal method, the tear load is the average of the five highest peaks recorded. Alternatively, a Sintech voltage tester can be used in the procedure.

Gripping Tension (Grip); This test measures the resistance to effective tension and the narrowing of a material. An area of one square inch is held at both ends of a 10.16 cm x 15.24 cm (4 x 6 inches) sample. The sample is pulled at a constant rate of extension to obtain results before the breaking point. The test is a measure of the breaking strength and elongation or tension of a fabric when it is subjected to a unidirectional tension. This test is known in the art and conforms to the specifications of ASTM D-5034-92 and D-5035-92 standards, and INDA IST 110.1-92, using a constant rate extension tension testing machine. This test also conforms to method 5100 of the federal test method standard 1191A. The results are expressed in pounds to break and percentage of narrowing before breaking. The higher numbers are indicative of a more narrow, more resistant fabric. The term "load" means the maximum peak load or force, expressed in units of weight, required to break or tear the sample in a stress test. The term "peak voltage", "total energy" or "peak energy" (PEN) means the total energy at under a load against the elongation curve as expressed in weight length. The term "elongation" or "percentage of narrowing" means the increase in length of a sample during a stress test. The values for grip strength and grip elongation are obtained using a specific cloth width, usually 4 inches (102 millimeters), an embraced width and a constant extension rate. The sample is wider than the clamp to give representative results of the effective resistance of the fibers in the clamped hook combined with additional strength contributed by the adjacent fibers in the fabric. The sample is burned in, for example, an Instron model TM, available from Instron Corporation, 2500 Washington St. , Canton, MA 02021, or a Thwing-Albert model INTELLECT II available from the Thwing-Albert Instrument Co., 10960 Dutton Rd., Phila., PA 19154, which have parallel clamps of 3 inches (76 mm) long. This closely simulates fabric tension conditions in actual use. The test can be conducted on dry or wet samples in the cross machine directions or machine directions. Alternatively, a Sintech voltage tester may be used, available from Sintech Corp., 1001 Sheldon Dr. Cary, North Carolina. High numbers in this test indicate a more narrow, stronger fabric.

Standard deviation (SD); The standard deviation as used in these examples represents a measure of dispersion and measures the average distance of a simple observation and its arithmetic mean. This is useful to understand how variable the game data can be. For example, the standard deviation can be used to allow the prediction of failure rates and / or to determine how much variability is acceptable in the final product. The standard deviation for each sample was calculated according to the following equation.

The use of n-l in the denominator instead of the more natural n was used because if n (instead of n-l) were used, it could result in a partial estimate of the population of the standard deviation. The use of n-l corrects this bias with the smaller sample sizes.

The formula for the standard deviation is: In the formula, "n" is the count of the number of observations. The distance of each observation (Xj) to the calculated average (x-bar) provides the basis for measuring the variability. The closer these observations are to the average, the smaller the standard deviation will be. If all observations are the same, the standard deviation may be zero. The deviations are square because the average is the "fulcrum" of the data (a point of balance between those observations greater than the average and those less than the average). If these deviations are not square, the sum may be zero. The square root of the sum is then taken to have the return value in the units of the original information.

Breathability Test (WVTR): A measure of the breathing capacity of a fabric is the water vapor transmission rate (WVTR). Circular samples measuring three inches (7.6 centimeters) in diameter supported from each of the test materials, and one-piece control of a CELGARD® 2500 sheet from Hoechst Celanese Corporation, of Charlotte, North Carolina. The CELGARD® 2500 sheet is a microporous polypropylene sheet. The three samples are prepared from each material. The test dish is a 68-1 vaporimeter vessel distributed by the Thwing-Albert Instrument Company of Philadelphia, Pennsylvania. One hundred millimeters of water are emptied into each vaporizer vessel and the individual samples of the test materials and control material are placed transversely over the open parts of the individual vessels. The bolt-on tabs are tightened to form a seal along the edges of the container, leaving the associated test material or control material exposed to the atmosphere of the environment over a circle of diameter of 6.5 centimeters that has an exposed area of approximately 33.17 square centimeters. The containers are placed in a forced air oven at 100 ° F (32 ° C) for 24 hours. The oven is at a constant temperature with external air circulating through it to prevent the accumulation of water vapor inside. An appropriate forced air furnace is, for example, a Blue M Power-O-Matic 60 furnace distributed by Blue M Electric Company of Blue Island, Illinois. Before placing in the oven the containers are heavy. After 24 hours, the containers are removed from the oven and weighed once more. The values of the water vapor transmission rate of the preliminary test are calculated as follows: Water Vapor Transmission Rate Test (WVTR) = (Weight loss in grams over 24 hours) x 315.5 g / m2 square / 24 hours The relative humidity inside the oven is not specifically controlled.

Under predetermined set conditions of 100 ° F (32 ° C) and a relative humidity of the environment, the water vapor transmission rate for CELGARD® 2500 control has been defined as being 5000 grams per square meter per 24 hours . Therefore, the control sample is run with each test and the preliminary test values are corrected to established conditions using the following equation: (WVTR) Water Vapor Transmission Rate = (WVTR test / WVTR control) x (5000 grams / square meter / 24 hours) Adhesion Strength Test (Adherence); This test determines the bond strength between the component layers of the laminated or bonded fabrics. The bond strength is the tensile force required to separate the component layers of a textile under specific conditions. In the adhesion or delamination test a laminate is tested by the amount of tension force required to pull apart a layer of film from a layer of non-woven fabric. The values for adhesion strength are obtained using a cloth sample width in samples of approximately 15.24 cm x 10.16 cm (6 x 4 inches) (6 inches in the machine direction). The folds of the samples are manually separated by a distance of about 5.08 cm (2 inches) along the length of the sample. A layer is then held in each jaw of a tested stress machine, and then it is subjected to a constant rate of extension. The maximum force (for example the peak load) necessary to complete the separation of the layers of certain components of the fabric. Two clamps are used, each with jaws of equal size, each measuring 2.54 cm (1 inch) parallel to the direction of the load application and 10.16 cm. (4 inches) perpendicular to the application of the load. The average peak load of a series of samples is calculated. The results are expressed in units of weight with the high numbers indicating a more resistant joined fabric. The sample is embraced, for example in an Instron model of TM, 1000, 1122, or 1130 available from the Instron Corporation, 2500 Washington St. , Canton, MA 02021, or a Sintech, Sintech QAD or Sintech Testworks voltage tester available from Sintech, Inc. to P.O. Box 14226, from Research Triangle Park, North Carolina 27709 or a Thwing-Albert, INTELLECT II model, available from the Thwing-Albert Instrument Company, 10960 Dutton Road, Philadelphia, PA 19154. The sample is then pulled apart for a distance of 5.08 cm (2 inches) at 180 ° separation and the average adhesion strength in grams. A constant rate of extension is applied of 12 ± 0.4 inches per minute (300 ± 10 millimeters per minute). The center of the width of the cross machine direction fabric on the side of the sample film is covered with 10.16 cm (4 in) wide adhesive tape or some other appropriate material in order to prevent the film from tearing apart during the proof. The adhesive tape is only on one side of the laminate so it does not contribute to the "strength of the sample." For the purposes of this test the dispersion index is the standard deviation for all data points collected in the specified adhesion region. Adhesion strength is the average force, expressed in grams, that is required to separate the fabric attached at 180 ° from an angle over a distance of 5.08 cm (2 inches).

Results Using the method of the invention, a laminate with an increase in tear resistance is produced. Tear resistance (as expressed in the grip arrest tests) is much greater than that expected for film / nonwoven laminates incorporating catalyzed metallocene polypropylene instead of catalysed polypropylene. Ziegler-Natta conventional. Specifically, the strength is much greater than that expected from the metallocene catalyzed inelastic polypropylene obtained under the designation 3854 from Exxon Chemical Company. This increase in tear resistance is especially apparent in the revision of the peak energy test values for the metallocene catalyzed laminates and comparing them with the values of the Ziegler-Natta catalyzed laminates in Table 2. These increased values of resistance to Tearing are even more surprising in view of the peak energy test results for the samples facing linked by single spinning and the samples facing the laminates joined by tapering as seen in Tables 3 and 4. In each of these materials , the peak energy values were higher for the Ziegler-Natta catalyzed materials as opposed to the metallocene catalyzed materials.

In addition, the use of metallocene-catalyzed polyolefins allows fine fibers which appear to aid in lamination and simultaneous bonding. It is theorized that such in-line processing avoids the high crystallinity which is present in the bound by preformed or aged yarn. The resulting laminate provides improved tear resistance properties as can be seen through the various test measurements. This improvement is in deference to the high temperatures and pressures necessary to thermally bond the bonded fabric by catalyzed polypropylene based spinning. High bonding temperatures of five to ten degrees are normally required for this polymer, which reduces the tensile strength. Although it is not intended to be limited by theory, it is theorized that yarn-bonded fibers are able to withstand heat at the bonding points without becoming hailstorm and still transferring sufficient heat to the film component. Even at the same strength of the fabric, the resistance to tearing is greater.

Therefore, polyolefins (e.g. polypropylene), with narrow molecular weight distribution (e.g., single site catalyst) allow the production of melt fused fibers with significantly increased mechanical properties even though the fibers are more difficult to bond thermally An online process that uses these materials produces a composite by a better tear resistance attributes than expected.

Even though the description has been described in detail with respect to the incorporations themselves, it may be appreciated by those with a skill in the art, after obtaining an understanding of the foregoing, that alterations to, variations of, and can easily be conceived of. equivalents of these additions. Therefore, the scope of the present invention should be assessed as that of the attached claims and any equivalents thereto.

TABLE fifteen twenty TABLE fifteen twenty fifteen

Claims (14)

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

1. A breathable barrier laminate with improved tear strength comprising: A layer of inelastic spin-bonded polyolefin fibers and a breathable film layer wherein the spin-linked layer is of a narrow molecular weight distribution; and the film is a polyolefin.

2. A breathable barrier laminate with improved tear strength comprising: A layer of inelastic spin-bonded polyolefin fibers and a breathable film layer wherein the spin-linked layer is of a narrow molecular weight distribution with polyolefin fibers of less than 2.5 denier per filament; and the film is a polyolefin.

3. The barrier laminate with capacity to breathe as claimed in clause 2, characterized in that the level of capacity to breathe is greater than 250 grams / square meter / 24 hours.

4. The barrier laminate capable of breathing as claimed in clause 3, characterized in that the level of capacity to breathe is greater than 1000 grams / square meter / 24 hours.

5. The breathable barrier laminate as claimed in clause 3, characterized in that said spunbonded composite is composed of an inelastic metallocene-catalyzed polypropylene material.

6. The breathable barrier laminate as claimed in clause 2, characterized in that the tear resistance is measured according to the grip tension test method.

7. The breathable barrier laminate as claimed in clause 6, characterized in that the tear resistance is measured in accordance with the peak energy test and such value is greater than 16,000 inch-pounds in the machine direction .

8. The breathable barrier laminate as claimed in clause 2, characterized in that it includes a second layer of polyolefin fibers linked by inelastic spinning on one side of the film layer capable of breathing opposite to the first bonded layer by spinning.

9. An online process for preparing a nonwoven film / fabric laminate comprising the steps of: a. forming a knitted fabric by spinning polyolefin of narrow molecular weight inelastic; b. provide a film with preformed breathing capacity; c. laminating said spin-linked fabric and said breathable film to form a laminate within 1 to 30 seconds of formation of said spunbonded fabric.

10. The process as claimed in clause 9, characterized in that said narrow inelastic molecular weight polyolefin is a metallocene catalyzed polypropylene.

11. A laminate produced by the processes as claimed in clause 9.

12. An absorbent article for personal care selected from a group consisting of diapers, training underpants, feminine hygiene products, and incontinence devices comprising the laminate as claimed in clause 2.

13. An absorbent article for personal care that includes: to. a top sheet permeable to liquid; b. a backup sheet; c. an absorbent core disposed between said top sheet and said backing sheet; wherein either the top sheet or the backing sheet comprises the laminate as claimed in clause 2.

14. Protective work clothing selected from a group consisting of surgical covers and gowns, coveralls, and lab coats comprising the laminate as claimed in clause 2. SUMMARY A laminate of nonwoven film / fabric is described for use as a fabric in personal care products. The laminate is formed of at least two layers in a bonded formation by film spinning. The spin-bonded layer of the laminate is preferably formed of metallocene-catalyzed polypropylene. The film layer is formed of a polyolefin which can be catalyzed by metallocene.