MXPA98001145A - Protective cover fabric including non-teji - Google Patents

Abstract

A protective cover made of a non-woven fabric of conjugated fiber having a basis weight of between about 1 and 8 ounces per square yard laminated with a film is provided herein. The conjugated fibers can be in a configuration such as sheath / core, side-by-side and islands at sea and can be formed of polyolefins and polyamides. Preferred fiber modalities are polypropylene-polyethylene fiber side by side and a sheath fiber / polyethylene / nylon core 6. The fabric is preferably extrusion coated with a polyethylene film to form the protective cover. The cover is lightweight, waterproof and provides sufficient tensile strength and breakage so that the cover can be used during transport of, for example, a boat or bar

Description

PROTECTIVE COVER FABRIC INCLUDING NON-WOVEN BACKGROUND OF THE INVENTION Fabrics are generally used for a wide variety of applications from cleaning cloths and diapers to car covers. These applications ask for materials having different properties and attributes. Some applications require fabrics which are highly humidifying, such as linings for diapers and feminine hygiene products, and which are soft, or absorbent type cleaners and towels, while others require resistance, for example fabrics. protective as cart and boat covers, and still others require repellent and barrier properties such as medicine-oriented fabrics, for example, sterilization wraps and surgical gowns.

The invention described herein is a protective cover for vehicles and equipment. Protective covers for various objects such as cars, boats and equipment have been sold for several years. These covers are made of a variety of materials such as canvas, non-woven fabric laminates, polyesters, and films. These are suitable for some applications but each has at least one characteristic which, if removed, will result in a higher cover. The canvas, for example, is very heavy and cumbersome to handle and still it is more when it is wet. Most films are weak and do not hold up well against strong wind, abrasion or puncture and indentation conditions. The desired characteristics of a protective cover are light weight for ease of use, good resistance to stress and breakage, high impact resistance and resistance to water penetration. It is also desired that a protective cover prevents abrasion of the article being covered.

It is therefore an object of this invention to provide a protective cover for equipment and vehicles which is light in weight, waterproof and which withstands strong wind conditions. It is another object of this invention to provide a protective cover which also provides impact resistance.

SYNTHESIS The objects of this invention are provided by a protective cover made of a non-woven fabric of conjugated fiber having a basis weight of between about 1 and 8 inches per square yard laminated with a film. The conjugated fibers may be in a configuration such as sheath / core, side by side, segmented pie and islands in the sea and may be formed of polyolefins and polyamides. The preferred fiber modalities are polypropylene-polyethylene spunbonded fiber side-by-side and a nylon / polyethylene sheath / core / fiber bonded 6. The fabric is preferably coated by extrusion with a polyethylene film to form the protective cover. The cover is lightweight, waterproof and provides sufficient resistance to tearing and tensioning so that the cover can still be used during transport of, for example, a boat.

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

As used herein the term "microfiber" means fibers of small diameter having an average diameter no greater than about 75 microns, for example, having an average diameter of from about 0.5 microns to about 50 microns, or more particularly, the microfibers can have an average diameter of from about 2 microns to about 40 microns. Another frequently used expression of fiber diameter is denier, which is defined as grams per 9,000 meters of a fiber and can be calculated as fiber diameter in square microns, multiplied by the density in grams / ce, multiplied by 0.00707. A lower denier indicates a finer fiber and a higher denier indicates a thicker or heavier fiber. For example, the diameter of a given polypropylene fiber as of 15 microns can be converted to denier by squareing, multiplying the result by 0.89 g / cc and multiplying by 0.00707. Therefore, a polypropylene fiber of 15 microns has a denier of about 1.42 (152 x 0.89 x .00707 = 1.415). Outside the United States of America the unit of measurement is more commonly the "tex", which is defined as grams per kilometer of fiber. The tex can be calculated as denier / 9.

As used herein the term "spunbond fibers" refers to fibers of small diameter which are formed by extruding the melted thermoplastic material as filaments of a plurality of capillary vessels usually circular and fine of a spinning organ with the diameter of the extruded filaments then being rapidly reduced as indicated for example in U.S. Patent No. 4,340,563 issued to Appel et al. and the U.S. Patent No. 3,692,618 issued to Dorschner et al., in 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 Number 3,502,763 granted to Hartman, US Patent No. 3,502,538 issued to Levy, and United States of America Patent Number 3,542,615 issued to Dobo and others. Spunbonded fibers are not generally sticky when they are deposited on a collecting surface. Spunbond fibers are generally continuous and have average diameters larger than 7 microns, more particularly between about 10 and 25 microns. As used herein the term "meltblown fibers" means fibers formed by extruding a melted thermoplastic material through a plurality of capillaries, usually circular and thin like melted threads or filaments into gas streams (e.g. air) usually hot, at high speed and converging which attenuate the filaments of the melted thermoplastic material to reduce its diameter, which can be at a diameter of microfiber Then, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a meltblown fabric randomly discharged. Such a process is described, for example, in the United States patent number 3,849,241 granted to Butin. Meltblown fibers are microfibers which can be continuous or discontinuous, these are generally smaller than 10 microns in average diameter and are generally sticky when deposited on a collecting surface.

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, etc., and mixtures and modifications thereof. the same. In addition, unless specifically limited otherwise, the term "polymer" will include any possible geometric configuration of the material. These configurations include, but are not limited to, isotactic, syndiotactic and random symmetries.

As used herein, the term "machine direction" or MD means the length of a fabric in the direction in which it is produced. The term "transverse direction of the machine" or CD means the width of the fabric, for example a direction generally perpendicular to the MD.

How to use aguí the term fiber of "monocomponent" refers to a fiber formed from one or more extruders using only one polymer. This does not mean that it excludes fibers formed from a polymer to which various amounts of coloring additives, antistatic properties, lubrication, hydrophilicity, ultraviolet stability, etc. have been added. These additives, for example titanium dioxide for coloring, are generally present in an amount of less than 5 percent by weight and more typically of about 2 percent by weight.

As used herein, the term "conjugated fibers" refers to fibers which are formed from at least two extruded polymers of separate extruders but spun together to form a fiber. Conjugated fibers are also sometimes referred to as multicomponent or bicomponent fibers. The polymers are usually different from one another even though the conjugated fibers can be monocomponent fibers. The polymers are arranged in essentially distinct zones placed essentially constantly across the cross section of the conjugated fibers and extend continuously along the length of the conjugated fibers. The configuration of such conjugated fiber can be, for example, a pod / core arrangement where one polymer is surrounded by another or can be a side-by-side arrangement or a segmented pie or an arrangement of "islands in the sea". The fibers conjugates are taught in U.S. Patent No. 5,108,820 issued to Kaneko et al., in U.S. Patent No. 5,336,552 issued to Strack et al., and U.S. Patent No. 5,382,400 issued to U.S. Pat. Pike and others. For bicomponent fibers, the polymers may be present in proportions of 75/25, 50/50, 25/75 or in any other desired proportions.

As used herein the term "biconstituent fibers" refers to fibers which have been formed from at least two extruded polymers from the same extruder as a mixture. The term "mixture" is defined below. The biconstituent fibers do not have the various polymer components arranged in different zones placed in a relatively constant manner across the cross-sectional area of the fiber and the various polymers are usually not continuous along the entire length of the fiber, forming instead fibrils or protofibrils which start and end at random. Biconstituent fibers are sometimes also referred to as multi-constituent fibers. Fibers of this general type are discussed in, for example, U.S. Patent No. 5,108,827 issued to Gessner. Bicomponent and biconstituent fibers are also discussed in the text Mixtures and Polymer Compounds by John A. Manson and Leslie H. Sperling, copyright 1976 by Plenum Press, a division of Plenum Publishing Corporation of New York, IBSN 0-306-30831-2, pages 273 to 277.

As used herein the term "mixture" means a combination of two or more polymers while the term "alloy" means a subclass of mixtures wherein the components are immiscible but have been compatibilized. The "misibility" and the "immissibility" are defined as mixtures having negative and positive values, respectively, for the free energy of the mixture. In addition, "compatibilization" is defined as the process for modifying the interfacial properties of an immiscible polymer mixture in order to make an alloy.

How to use aguí, the union through air or " " means a joining process of a non-woven bicomponent fiber fabric in which the air which is hot enough to melt one of the polymers from which the fibers of the fabric are made is forced through the fabric . The air speed is between 100 and 500 feet per minute and the residence time can be as long as 6 seconds. The melting and resolidification of the polymer provides the bond. Bonding through air has a restricted variability and is generally seen as a second step joining process. Since the union through air requires the melting of at least one component to achieve the union is restricted to fabrics with two or more components such as bicomponent fiber fabrics or fabrics which include a heat activated adhesive.

As used herein, the term "spin-sewn" means for example, the sewing of a material according to U.S. Patent No. 4,891,957 issued to Strack et al. Or U.S. Patent Number 4,631,933. awarded to Carey, Jr.

As used herein, the term "ultrasonic bonding" means a process carried out, for example by passing the fabric between a sonic horn and an anvil roll as illustrated in U.S. Patent No. 4,374,888 issued to Bomsleager.

As used herein, "thermal bonding" involves passing a fabric or fabric of fibers that are to be joined between a calendered or heated roller and an anvil roller. The calendered roll is usually even if not always, a pattern roller and in some manner so that the entire fabric is not bonded through its entire surface. As a result of this, various patterns have been developed for calendering rolls due to functional as well as aesthetic reasons. An example of a pattern has points and is the Hansen Pennings pattern or "H &P" with around an area 30 percent joined with about 200 joints / square inch as taught in U.S. Patent No. 3,855,046 issued to Hansen and Pennings. The H &P pattern has a square point or bolt joint areas where each bolt has a side dimension of 0.965 millimeters, a gap of 1,778 millimeters between bolts, and a joint depth of 0.584 millimeters. The resulting pattern has a bound area of about 29.5 percent. Another typical point union pattern is the "EHP" or expanded Hansen Pennings pattern which produces a 15 percent area joined with a square bolt having a side dimension of 0.94 millimeters, a bolt spacing of 2,464 millimeters and a depth of 0.991 millimeters Another typical point union pattern is designated "714" which has square bolt joint areas where each bolt has a side dimension of 0.023 inches, a spacing of 0.062 inches (1.575 mm) between the bolts, and a depth 0.033 inch (or .838 millimeter) joint. The resulting pattern has a bound area of about 15 percent. However, another common pattern is the star-C pattern which has a bound area of about 16.9 percent. The star-C pattern has a bar in the transverse direction or a "corduroy" design interrupted by shooting stars. Another common pattern includes a diamond pattern with slightly off-center and repetitive diamonds and a wire weave pattern that looks like the name suggests as a window blind. Typically, the percent of bonded area varies from about 10 percent to about 30 percent of the area of the laminated fabric bonded. As is well known in the art, knit bonding keeps laminated layers together as well as one that imparts integrity to each individual layer by joining the filaments and / or fibers within each layer.

As used herein, the term "protective cover" means a cover for vehicles such as cars, trucks, boats, airplanes, motorcycles, bicycles, golf carts, etc., and covers for equipment that is often left outdoors. as grills, garden and patio equipment (mowers, rototrildoras, etc.) and meadow furniture. Protective covers can be used to cover stationary items or as transportation decks, for example, boat covers for trailers mounted on trailers and towed.

TEST METHODS Weight Impact Testing Falling Gardner: This test measures the maximum impact force before damage by a 4-pound weight that falls on a painted metal sheet covered by the fabric to be tested. The inches of height test measurements above the panel to which the half-inch-diameter rod was raised with a rounded tip before the impact, and a higher reading indicates a relatively more protective fabric. This test is carried out according to the test method ASTM D-2794-84 and the results are reported in units in inches-pounds. The test reported here was carried out by the paint research associates of Ypsilanti, Michigan.

Grip Tension Test: Grip tension test is a measure of the resistance to breakage and elongation or tension of a fabric when subjected to a unidirectional tension. This test is known in the art and conforms to the descriptions of the 5,100 method of standard federal test methods number 191A. The results are expressed in pounds until the break and the percent stretch before the break. The upper numbers indicate a more stretchable and stronger fabric. The term "load" means the maximum load or force, expressed in units of weight, required to break or tear the specimen to a stress test. The term "voltage" or "total energy" means that the total energy under a load against an elongation curve is expressed in units of length-weight. The term "elongation" means the increase in length of a specimen during a stress test. The values for the grip strength resistance and the grip elongation were obtained using a specific width of fabric, usually of 102 millimeters, grip width and a constant extension rate. The sample is wider than the clamp to give representative results of the effective strength of the fibers in the grip width combined with additional strength contributed by the adjacent fibers in the fabric. The specimen is grasped in, for example, an Instron Model TM apparatus available from Instron Corporation of 2500 Washington St. , Canton, MA 02021, or a Thwing-Albert Model INTELLECT II available from the Thwing-Albert Instru Company, 10960 Dutton Road, Philadelphia, PA 19154, which has parallel clamps 76 millimeters long. This closely simulates fabric tension conditions in actual use.

Trapezoidal Tear Test: The trapezoidal tear test or "Trap" is a tension test applicable to both woven and non-woven fabrics. The full width of the specimen is grasped between the clamps, therefore the primary test measures the joint or interlock and strength of the individual fibers directly in the stress load, rather than the strength of the composite structure of the fabric as a whole. The procedure is useful for estimating the relative ease of tearing a fabric. This is particularly useful in determining any noticeable difference in strength between the machine direction and the cross direction of the fabric. In the performance of the trapezoidal tear test, a line of a trapezoid is drawn on a specimen of 75 by 152 millimeters with the largest dimension in the direction being tested, and the specimen is cut in the trapezoid shape. He trapezoid has a side of 102 millimeters and a side of 25 millimeters which are parallel and which are separated by 76 millimeters. A small preliminary cut of 15 millimeters is made in the middle of the shorter of the parallel sides. The specimen is secured in, for example, an Instron model TM apparatus, available from Instron Corporation, 2500 Washington Street, Canton, MA 02021, or a Thwing-Albert model INTELLECT II apparatus available from Thwing-Albert Instrument Company, 10960 Dutton Road, Philadelphia, PA 19154, which has parallel clamps 76 millimeters long. The specimen is secured along the non-parallel sides of the trapezoid so that the fabric on the longer side is loose and the fabric along the shorter side is taut, and with the cut in half between the clamps. A continuous load is applied on the specimen so that the tear propagates through the width of the specimen. It should be noted that the longest direction is the direction being tested even when the tear is perpendicular to the length of the specimen. The force required to completely tear the specimen is recorded in pounds with the upper numbers indicating superior resistance to tearing. The test method used conforms to the standard test ASTM D-1117-14 except that the tear load is calculated as the average of the highest and highest peaks recorded rather than the lowest and highest peaks. Five specimens should be tested for each sample.

Mullen Break Test: The Mullen Break Test gives the amount of force needed to drill a fabric. The Mullen break test is carried out in accordance with ASTM D-3786 entitled Hydraulic Breakage Resistance of Woven and Non-Woven Fabrics and the results are reported in pounds.

Volume Test: The volume test gives the thickness of a fabric in inches .. The test used here used a 5-inch platform.

Hydrohead: 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 will hold before a predetermined amount of liquid passes through it. A cloth with a higher hydrohead reading indicates that it has a greater barrier to liquid penetration than a cloth with a lower hydro head. The hydrohead test is carried out according to federal test standard number 191A, method 5514.

Melt Flow Rate: The melt flow rate (MFR) is a measure of the viscosity of a polymer.

The melt flow rate is expressed as the weight of the material which flows from a capillary of known dimensions under a specified load or cut-off rate for a measured period of time and is measured in grams / 10 minutes at 230 degrees Celsius according to, for example, the ASTM 1238 test, condition AND.

Cold Cracking Test: The cold cracking test measures how well a fabric supports cold temperatures. The test is also referred to as the Gruel cold bending method and is carried out according to ASTM D-1912 at 0 degrees centigrade and minus 30 degrees centigrade.

DETAILED DESCRIPTION OF THE INVENTION A protective cover is provided here for many applications in various fields of use. For example, consumers can use this cover for boat covers, car covers, airplane covers, and as a cover for equipment that is normally stored outside, such as grills, meadow care equipment, etc. . The cover can also be used to protect military equipment such as tanks and artillery pieces from the elements. The protective cover described here is also suitable for covering oil processing equipment, pumps, compressors and valves.

The protective cover described herein has the added advantage of being suitable for transporting a covered article without damage to the cover or covered article. Although many tires are not strong enough for the use of transportation, the cover of this invention is. This avoids having to change covers when an item is going to move and avoids the purchase of two types of covers; one for storage and one for transportation. This results in very large savings of time and money for the user.

In addition, since the cover of this invention is quite light and thin, it is easier to use it or not to simply be stored, and thus provide protection for a longer period of time than a heavy, bulky and difficult to use cover .

The protective cover of this invention is a novel laminate of a non-woven fabric and of a film, any of which may be multi-layered. The non-woven fabric can be a monocomponent, conjugated or multi-constituent fabric even when the fibers are conjugated are preferred. The film is preferably a polyolefin film, particularly polyethylene.

The fibers from which the non-woven fabric of this invention is made can be produced by the processes of meltblown or spunbond which are well known in the art, even when spunbonding is preferred. These processes generally use an extruder to supply the melted thermoplastic polymer to a spinning organ wherein the polymer is fiberized to give fibers which may be short or larger in length. The fibers are then pulled, usually pneumatically, and deposited on a foraminous mat or band to form the non-woven fabric. The fibers produced in the meltblown and meltblown processes are microfibers as defined above. The conjugated fibers are produced using separate extruders for the polymers, which are usually two in number. Methods for making the conjugate fibers are taught in U.S. Patent No. 5,382,400 issued to Pike et al. Which has been assigned to the same assignee as this application and which is hereby incorporated by reference in its entirety.

The non-woven fabric component of this invention can be a multilayer laminate even if it is preferred that it not be, since the inventors currently do not see an advantage for the additional layers. In fact, the weight of the cover could be adversely affected unless the weight of the total nonwoven was kept constant. However, in case a multi-layer nonwoven is used one such example is a mode in which some of the layers are spunbonded and some are meltblown such as spunbond / meltblown / spunbonded (SMS) laminate as described in U.S. Patent 4,041,203 to Brock et al. U.S. Patent No. 5,169,706 issued to Collier et al. and U.S. Patent No. 4,374,888 issued to Bomslaeger. Such lamination can be done by depositing in a sequence on a mobile forming strip first a layer of spunbond fabric, then a layer of meltblown fabric and at least one other layer of spunbonded and then joining the laminate in the manner described below. Alternatively, the fabric layers can be made individually, collected in rolls, and combined in a separate bonding step. Such fabrics usually have a basis weight of from about 6 to about 400 grams per square meter (gsm) or from about 0.1 to 12 ounces per square yard (osy).

The non-woven fabric component of this invention is preferably a spin-bonded material and preferably between 1 and 8 ounces per square yard (34 grams per square meter to 272 grams per square meter). The polymers which can be used to produce the spin-bonded component are extrudable compositions of thermoplastic polymers such as polyolefins, polyamides, polyethylene terephthalate and polyesters. Of polyolefins, polyethylene and polypropylene are preferred. A preferred structure of such fibers is like a fiber bonded by conjugated spinning of two polymers wherein one of the polymers is a polyolefin and the other is a polyamide. Another preferred structure is a side-by-side polypropylene and polyethylene side-by-side spun fiber. It is also possible that one or all of the conjugated fiber extruders extrude a biconstituent or fiber alloy mixture made of more than one polymer.

Many polyolefins are available for the production of the fiber, for example, polyethylenes such as Dow Chemical's linear low density polyethylene ASPUN® 6811A, 2553 LLDPE and 25355 and 12350 high density polyethylene are such suitable polymers. The polyethylenes have melt flow rates, respectively, of about 26, 40, 25, and 12. The fiber formers include the PD 3445 polypropylene from Exxon and the PF-304 from Himont Chemical Company. Many other polyolefins are commercially available.

The polyamide which can be used in the practice of this invention can be any polyamide known to those skilled in the art including copolymers and mixtures thereof. Examples of polyamides and their synthesis methods can be found in the book "Polymer Resins" by Don E. Floyd (Library of Congress catalog number 66-20811, Reinhold Publishing, New York, 1966). Polyamides particularly commercially useful are nylon 6, nylon 6, 6, nylon-11 and nylon-12. These polyamides are available from a number of sources such as Nyltech North America of Manchester, NH, Emser Industries of Sumter, South Carolina (Grilon® &Nilones Grilamid®) and Atochem Inc. Polymers Division, of Glen Rock, New Jersey (Nilones Rilsan®), among others.

In addition, a compatible adhesive resin can be added to the extrudable compositions described above to provide the self-bonding adhesive materials. Any adhesive resin can be used which is compatible with the polymers and can withstand the high processing temperatures (for example extrusion). If the polymer is mixed with processing aids such as, for example, polyolefins or spreading oils, the adhesive resin must also be compatible with those processing aids. Hydrogenated hydrocarbon resins are the preferred adhesive resins due to their better temperature stability. The adhesives from the REGALREZ® and ARKON® P series are examples of hydrogenated hydrocarbon resins. The light ZONATAC® 501 resin is an example of linking terpenehydrocarbon. REGALREZ® hydrocarbon resins are available from Hercules Incorporated. Resins of the ARKON® P series are available from Arakawa Chemical (USA) Incorporated. Adhesive resins as described in the patent of the United States of America number 4, 787,699 incorporated aguí by reference are adequate. Other adhesive resins which are compatible with the other components of the composition and which can withstand the high processing temperatures can also be used.

It is also possible to have other materials mixed in smaller amounts with the polymers used to produce the film and / or nonwoven layer according to this invention as the fluorocarbon chemicals to improve the chemical repellency which can be, for example, any of those taught in U.S. Patent No. 5,178,931, fire retardants, ultraviolet radiation resistance improving chemicals and pigments to give each layer the same or different colors. Fire retardants and pigments for thermoplastic meltblown and spunbond polymers are known in the art and are internal additives. A pigment, for example Ti02, if used, is generally present in an amount of less than 5 percent by weight of the layer while other materials may be present in a cumulative amount of less than 25 percent by weight.

A chemical for improving resistance to ultraviolet radiation can be, for example, hindered amines and other commercially available compounds. The hindered amines are discussed in the patent of the States United States of America number 5,200,443 granted to Hudson and the examples of such amines are Hostavin TMN 20 from American Hoescht Corporation of Somerville, New Jersey, Chimassorb® 944 FL from Ciba-Geigy Corporation of Hawthorne, New York, Cyasorb UV-3668 from American Cyanamid Company of Wayne, New Jersey and Uvasil-299 of Enichem Americas, Inc. of New York.

Articles made from these laminates of this invention may also have topical treatments applied to them for more specialized functions. Such topical treatments and their methods of application are known in the art and include, for example, alcohol repellency treatments, antistatic treatments and the like, applied by spraying, embedding, etc. An example of such a topical treatment is the application of the Zelec® antistatic (available from E. I. DuPont of Wilmington, Delaware).

Specific combinations for conjugate fiber and film laminate include polypropylene / nylon side-by-side spinnable fibers with polypropylene film, polyethylene / nylon side-by-side spinnable fibers with polyethylene film, bonded fibers by side-by-side spinning of polypropylene / nylon with EVA film, fibers bonded by sheath spinning / polyethylene core / nylon with polyethylene film, sheath-bonded fibers / polypropylene core / nylon with polypropylene film, bonded fibers by spinning side by side polypropylene / polyethylene with polypropylene film, side-by-side polypropylene / polyethylene fibers with polyethylene film, sheath / polyethylene core / polypropylene with polyethylene film.

The film component layer can be extruded using any method known in the art to be effective. The film component is produced in a thickness of from about 0.5 mils to about 8 mils, or more particularly from about 2 to 4 mils and can be made from any number of layers as long as the total of layers is within these ranges indicated.

The film can be made from those polymers commonly known to be useful in the production of films, particularly ethyl vinyl acetate (EVA), polyvinylchloride (PVC), polyamides and polyolefins with polyolefins being preferred. Among the polyolefins, polypropylene and polyethylene are preferred. The film compositions of this invention are relatively simple since the inventors have found that such compositions give good adhesion to conjugated fiber fabrics without resorting to relatively more complicated formulas and are simpler to process and relatively inexpensive. The formulas of, for example, U.S. Patent No. 4,368,232 are not desired in the practice of this invention.

The film layer can also be made of polymers which are semi-crystalline / amorphous or heterophasic in character. Heterophasic polymers are described in European patent application EP 0444671 A3 (based on application number 91103014.6), European patent application EP 0472946 A2 (based on application number 91112955.9), European patent application EP 0400333 A2 (based on on the application number 90198051.5), the patent of the United States of North America number 5,302,454 and the patent of the United States of North America number 5,368,927. Heterophasic polymers are commercially available under the trade designation "Cattalloy" from Himont Chemical Company of Wilmington Delaware and polypropylene. Specific commercial examples are Catalloy® KS-084P, Catalloy® KS-085 and Catalloy® KS-057P. The film layer may also have small amounts of additives present to improve processability such as low density polyethylene (LDPE) such as those available from Quantum Chemical Company under the designation NA 334 or those available from Rexene under the designation 1058 LDPE. Many similar LDPE polymers are commercially available.

The film and the non-woven layer can also be adhesively bonded together by the use of commercial adhesives which are known to those skilled in the art. Examples include the adhesive of the patent of the United States of America number 5,149,741 incorporated here by reference granted to Alper and others and assigned to Findley Adhesive, Inc., of Wauwatosa, Wisconsin. The coating is an adhesive which comprises about 15 to 40 parts of a styrene-isoprene-styrene block copolymer wherein the styrene content of the copolymer is from 25 to 50 percent by weight, about 40 to 70 parts by weight. a compatible adhesive resin such as, for example, pentaerythritol esters, about 5 to 30 parts of paraffinic-naphthenic oil and 0.1 to 2 parts, by weight, of a phosphite antioxidant, a hindered phenolic antioxidant and a stabilizer, wherein The adhesive has a melt viscosity of no more than 6000cP at 325 degrees F.

Alternatively, the film can be formed directly on the non-woven fabric and set in contact therewith. This method ensures that the contact between the two components is intimate and that the adhesion between the two is strong, particularly if the same polymer is present in both components, it is preferred. This method, known or extrusion coating, involves extruding the polymer as a film directly onto the non-woven fabric and then passing the non-woven coated film through a "pressure point" or roller arrangement wherein the film and the Non-woven are pressed together for a strong bond. The pressure of the pressure point can be controlled to vary the force used to compress the two components together.

The film can also be attached to the non-woven layer by other means such as stitching and ultrasonic bonding.

The fabric of this invention can be produced in standard commercial widths. These standard commercial widths can be joined together in seams to produce protective covers of specific configurations to precisely adjust particular vehicles. The seams can be joined by using a heat sealable polymer tape such as a polyethylene coated canvas, a polypropylene coated canvas, an EVA coated canvas or a PVC tape as is known in the art. The tape is placed on the edges of both pieces of fabric and heated to a temperature which will cause the polymer to adhere to both pieces. This temperature has been found to be between about 600 and 650 degrees F for polyethylene, between about 550 and 675 degrees Celsius for EVA and about 1,000 degrees Celsius for PVC. It has also been found that the fabric of this material itself can be used as a sealing tape. This is not the case with PVC / nonwoven fabrics due to the adhesive layer used to join the two. The seams can also be joined by conventional ultrasonic or sewn connection.

A number of examples were prepared using several polymers. Descriptions of the examples and competitive fabrics are provided below and the test results of these examples as well as of the commercially available competitive materials are provided below in Table 1. All fabrics passed the cold cracking test.

EXAMPLE This material is a fiber fabric bonded with polyethylene / polypropylene side-by-side yarn conjugate of 102 grams per square meter on which a 4 mil polyethylene film was extruded. The fiber polymers were Exxon PD 3445 polypropylene and Dow ASPUN® 6811 A polyethylene. The film polymer was Rexene 5080. The film had additives in lower amounts for ultraviolet and color resistance. The pressure point pressure was 40 pounds.

EXAMPLE 2 This material is a fiber cloth bonded by conjugate nylon 6 / sheath / core polyethylene 2.5 oz. Per square yard onto which a 1 mil polyethylene film was extruded. The fiber polymers were polyethylene Dow ASPUN® 6811 A and nylon 6 of Nyltech from Nyltech North America.

The film polymer was Rexene 5080. The film had additives in lower amounts for ultraviolet resistance and color. The clamping point pressure was 60 pounds.

EXAMPLE The material is a fiber fabric bonded by polyethylene / polypropylene side-by-side spinning of 3 ounces per square yard on which a 4 mil film was extruded. The fiber polymers were Exxon PD 3445 polypropylene and Dow ASPUN® 6811 polyethylene. The film polymer was Uvin-U35 ethylvinyl acetate from Quantum Chemical. The film had additives in smaller amounts for ultraviolet resistance and color. The pressure point pressure was 40 pounds.

EXAMPLE This material is a fiber fabric bonded by polypropylene yarn of 3 ounces per square yard on which a 4 mil film was extruded. The fiber polymer was Exxon PD 3445 polypropylene. The film was a heterophasic polymer available from Himont Chemical under the trade designation Catalloy KS-085. The film had additives in smaller amounts for ultraviolet resistance and color.

The pressure point pressure was 40 pounds.

EXAMPLE This material is a fiber fabric bonded by polypropylene yarn of 3 ounces per square yard on which a 4 mil film was extruded. The fiber polymer was Exxon PD 3445 polypropylene. The film was a polypropylene available from Rexene. The film had additives in smaller amounts for ultraviolet resistance and color. The pressure point pressure was 40 pounds.

EXAMPLE 6 This material is a fiber fabric bonded by polyethylene / polypropylene side-by-side spinning of 136 grams per square meter onto which a 4 mil polyethylene film was extruded. The fiber polymers were Exxon PD 3445 polypropylene and Dow ASPUN® 6811 A polyethylene. The film polymer was Rexene 5080. The film had additives in lower amounts for ultraviolet resistance and color. The pressure point pressure was 60 pounds.

EXAMPLE This material is a fiber cloth bonded by polyethylene / polypropylene spinning side by side 4 oz. Per square yard on which a 4 mil polyethylene film was extruded. The fiber polymers were Exxon PD 3445 polypropylene and Dow ASPUN® 6811 A polyethylene. The film polymer was Rexene 5080. The film had additives in lower amounts for ultraviolet resistance and color. The pressure point pressure was 40 pounds.

EXAMPLE This material is a fiber fabric bonded by polyethylene / nylon 6 sheath / core conjugate of 85 grams per square meter on which a 4 mil polyethylene film was extruded. The fiber polymers were Dow ASPUN® 6811 A polyethylene from Dow and nylon 6 Nyltech from Nyltech North America. The film polymer was Rexene 5080. The film had additives in lower amounts for ultraviolet resistance and color. The pressure point pressure was 40 pounds.

COMPETITIVE 1 This material is a composite of 465 grams per square meter having a non-woven polyester fiber fabric and a PVC film thereon. This material is commercially available from Haartz Crop., 87 Hayward Road, Acton, MA 01720-3000 and is believed to have a 50/50 weight ratio of film and fiber which are adhesively bonded together.

COMPETITIVE 2 This material is a compound of 353 grams per square meter having a non-woven polyester fiber fabric and a PVC film thereon. This material is commercially available as a transportation cover from Marine Specialties Group, a subsidiary of G &T Industries, 475 36th Street, Grand Rapids, MI 49548.

COMPETITIVE This material is a relatively thick polypropylene film having a basis weight of 4.4 ounces per square yard (149 grams per square meter) and has a thickness of about 15 mils. m or CN N Thus it can be seen from the data in Table 1 that the protective covers of this invention are much lighter "than most of the competitively available products, but still provide good resistance to stress and breakage. The inventors believe that competitive fabrics deliver unnecessarily high tensile strength and breakage at the cost of being extremely heavy. Such a heavy cover is often not used due to the difficulty of putting it in place and removing it from a vehicle or piece of equipment. The invention described herein is relatively lightweight, preferably less than 8 ounces per square yard and even more preferably between about 2 and 5 ounces per square yard. The fabric is waterproof but still provides sufficient resistance to tension and breakage to make it functional for a long time. In particular, the fabric of this invention provides a breaking strength of above about 55 pounds which is sufficient to cover the use for storage and also for a cover used to protect something, for example, a boat during transport. Example 8 provides a breaking strength above about 100.

It has been found that a particular embodiment, using a polypropylene / nylon sheath / core fabric provides a surprisingly superior impact strength and thus will protect a much better article than other fabrics. This is particularly advantageous when the The cover of this invention is used, for example, as a car cover in an area where the vehicle can be "pealed" by the doors of adjacent vehicles. The inventors are currently unaware of the method of operation of this impact resistance protection mechanism. The impact resistance of various fabric materials is given in Table 2. The impact resistance reported in Table 2 is the Gardner impact strength test step of normalized pounds weight by dividing the base weight of the fabric and the thickness and then multiply by 10,000.

T A B L A 2 Fabric Impact Resistance Weight Base (oßv) Discovered 0 0 Joined by Polypropylene Yarn 30 1 Nylon Fabric 38 1.5 Nylon sheath PP / Core by Yarn 50 1 Cotton Flannel 2 8.1 Poly-Cotton 3 3.9 Sunbrella® Fabric 2 8.7 The last fabric listed in Table 2 is a fabric Sunbrella® from Glen Raven Mills Inc. of Glen Raven, Carolina North. Sunbrella® fabric is a modified acrylic or "modacrylic" woven fabric. The fabrics are believed to be made of acrylonitrile copolymers and an initial halogen-containing monomer. Sunbrella® fabric is typically treated with a fluorocarbon compound. The tested material was 295 grams per square meter.

The results show that PP sheath core / nylon 6 gave a surprisingly good impact resistance and is 25 to 40 percent more effective in protecting a covered surface from impacts than any polymer individually. The reason for this is not currently known by the inventors.

Although only a few example embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications to the exemplary embodiments are possible without departing materially from the novel teachings and advantages of this invention. Therefore, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, the media clauses plus function are intended to cover the structures described herein as carrying out the recited function and not only the structural equivalents but also the equivalent structures. Thus even when a screw and a nail may not be equivalent structures in the sense that a nail employs a cylindrical surface to secure wooden parts toer, while a screw employs a Helical surface, in the environment of the fastening of wooden parts a screw and a nail can be equivalent structures.

Claims (14)

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

1. A protective cover comprising a non-woven fabric of conjugated fiber having a basis weight of between about 1 and 8 ounces per square yard, laminated to a fabric having at least one layer and having a thickness of between about 0.5 and 8. mils

2. The protective cover as claimed in clause 1 characterized in that said conjugate fiber is a spunbonded fiber composed of at least two extruded polymers of separate extruders in a configuration selected from the group consisting of sheath / core, side by side side and islands in the sea.

3. The protective cover as claimed in clause 2, characterized in that at least one polymer of said conjugated fiber is composed of a mixture of biconstituent polymers.

4. The protective cover as claimed in clause 1 characterized in that said conjugated fiber is produced from polymers selected from the group consisting of polyolefins and polyamides.

5. The protective cover as claimed in clause 4 characterized in that said conjugated fiber is produced from polyolefins and said polyolefins They are made of polypropylene and polyethylene.

6. The protective cover as claimed in clause 4 characterized in that said conjugated fiber is produced from polyolefins and polyamides and said polyolefin is polyethylene.

7. The protective cover as claimed in clause 4 characterized in that said conjugated fiber is produced from polyolefins and polyamides and said polyolefin is polypropylene.

8. The protective cover as claimed in clause 1 characterized in that said film is a single layer made of a polymer selected from the group consisting of polyolefins, heterophasic polymers and EVA.

9. The protective cover as claimed in clause 8 characterized in that said film is made of a polyolefin and said polyolefin is polyethylene.

10. The protective cover as claimed in clause 1 characterized in that said film is adhered to said non-woven fabric by a method selected from the group consisting of adhesive bonding, seam bonding, coating bonding with extrusion and ultrasonic bonding.

11. A protective cover comprising a fiber cloth bonded by polyethylene-polypropylene side-by-side conjugate spinning having a basis weight of between about 2 and 5 ounces per square yard, onto which a polyethylene film having a thickness has been extruded between about 0.5 and 5 mils to form a laminate, wherein said laminate has a breaking strength of above about 55 pounds, is waterproof, and wherein said laminate is a protective cover having heat sealable seams, for vehicles and equipment.

12. The protective cover as claimed in clause 11 characterized in that said cover is used to protect a ship.

13. The protective cover as claimed in clause 11 characterized in that said cover is used to protect a car.

14. A protective cover consisting essentially of a fiber fabric bonded by polyethylene-nylon sheath / core conjugate yarn having a basis weight of between about 2 and 4 ounces per square yard, onto which a polyethylene film having been extruded a thickness of between about 0.5 and 5 mils to form a laminate, wherein said laminate has a breaking strength above about 100 pounds, is based on water proof and provides an impact resistance of at least 50 percent or greater than the polypropylene spunbonded web, and wherein said laminate is a protective cover having heat sealable seams, for vehicles and equipment. SUMMARIZES A protective cover made of a non-woven fabric of conjugated fiber having a basis weight of between about 1 and 8 ounces per square yard laminated with a film is provided herein. The conjugated fibers can be in a configuration such as sheath / core, side by side and islands in the sea and can be formed of polyolefins and polyamides. Preferred fiber modalities are polypropylene-polyethylene fiber side by side and a sheath fiber / polyethylene / nylon core 6. The fabric is preferably extrusion coated with a polyethylene film to form the protective cover. The cover is lightweight, waterproof and provides sufficient tensile and breakage resistance so that the cover can be used during transport of, for example, a boat or boat.