MXPA98010864A - Filamento conjugado autorrizable and band without seam formed from the same and method to make my - Google Patents

Abstract

The side-by-side conjugate filaments made of thermoplastic elastomers and spin-linked type polypropylenes exhibit an extremely high propensity to autorrize. At appropriate polymer ratios and appropriate processing conditions (with aerodynamic or mechanical pulling) the ripple develops spontaneously after relaxation of the attenuating force. This amount of curling and the degree of the elastic properties will depend on the elastomer content and the processing conditions. The resulting ripple is typically in the range of 25-200 crimps per inch. This curling combination is exceptionally high and an elastomer component imparts stretch and recovery property. The filaments can be wrapped around a cylindrical support structure to create an elastic band without continuous constura, useful for notching articles to the body.

Description

FILAMENTO CONJUGADO AUTORRIZABLE AND BAND WITHOUT SEAM FORMED OF THE SAME AND METHOD TO MAKE THE SAME FIELD OF THE INVENTION The present invention relates to a self-hardening conjugate filament formed by releasing a d attenuation force applied to the melted filaments produced by a melt attenuation apparatus. You can form a continuous seamless web having improved stretch and recovery properties of the self-healing filaments.

BACKGROUND OF I-A INVENTION Current methods for obtaining the "body fit" characteristics in personal care products use mechanical fasteners, woven elastic band structures, elastic non-woven laminates, or elasticated glued yarns. All have disadvantages in some grad when they are measured against three criteria of cost performance and aesthetics. With respect to the elastic components, the development of elastic non-woven laminates (for example the waist elastic, the stretchable laterale ® panels, the Lycra thread laminates) have been leveled and products to give body fitting innovations with the appearance of cloth type aesthetics. These stretchable structures are manufactured in a planar or "flat" geometry. This form adapts to the existing product and base assembly technologies; however, it introduces complexities that require sophisticated solutions, especially in the conversion process. The invention when used in the form of a tubular structure or seamless band provides an alternative to such flat structures.

The bicomponent filaments in a side-by-side configuration are defined as having a "conjugate" arrangement. Almost all synthetic conjugated fibers have an autorrizable potential. The curl, helical structure, usually also manifests itself in the melted-spun filaments after they have been subjected to post-treatment that induces shrinkage in the components.

(The treatments commonly used are heat, humidity and narrowing-stretching). The curling potential of the conjugate fibers is primarily related to the difference in the shrinkage characteristics of the individual components. The shrinkage results of the internal structural changes that are triggered by the phase changes depend on time and / or temperature (crystallization factors are the most prevalent).

The processing conditions will not produce helical ripple without a shrinkage difference between the components. Even the ripple resulting from the symmetrical cooling of the polypropylene is due to a conjugate arrangement of different crystalline structures. However, these impact extension of the curly development. Because most of the authorizing forces are low, they are usually overcome by attenuation forces. As a result of this, most of the conjugated and spun filaments do not exhibit ripple. For certain combinations of components, the spinning conditions can be found to result in spontaneous curling (once the pulling forces are relaxed) without the need for further treatment.

Curling in a fiber causes greater volume in the form of the fabric, changes the tactile properties (eg, sensation and fall), and has the potential to impart additional stretch characteristics. This is the ac for both the filaments (autorrized and those of mechanically induced curling.) In the self-hardening filaments the ability to stretch arises from its helical spring type structure which is geometrically distinct from the "saw tooth" structure of the mechanically curled filaments stretch consists of both aspects of extension and recovery.In extension, the curled fiber shows a non-linear low tension response when the curled geometry is deformed, a high voltage response when the fiber is fully extended. If this happens after the extension, it is by "re-winning" the curly.Because its recovery is related to re-winning the ripple (a physical manifestation of relatively low internal strengths), the conventional self-healing fibers lack the retraction force of the Lycra from other purely elastic fibers. The retracting force of the elastomers are a consequence of their molecular structure ® The Lycra-type filaments (polyurethane spun in sec rubber yarns, and thermoplastic elastomers (for example ® ® Kraton polymers, Armitel polymers, melted polyurethanes spun yarns), all are segmented block copolymers L elastic properties arise from alternating the molecular sequences of soft chain segments joined together c segments of rigid or hard chain In a relaxed state the soft chains lie in a tangled disorder, under tension the chains are stretched while they always want to return to a tangled natural state.While elastomeric fibers develop an immediate molecular resistance under tension, such resistance occurs for the crimped fibers until curling is removed and the cold-pulling deformation begins.

D melted polyurethane-based fibers, as described in the prior art, did not exhibit spontaneous elastomeric properties (recovery after stretching). Rather these fibers must be aged for a period of time, something like about 24 hours, which significantly increases the cost and time to produce the product. Additionally, post-training treatment, eg, stretching, is normally required. Polyurethane filaments are not known to curl when they are attenuated from melting. See, for example, U.S. Patent Nos. 3,379,811, 4,551,518, and 4,660,228.

U.S. Patent No. 4,071,348 to Chamberlain, issued to Chamberlain, discloses a curled bicomponent filament composed of a polyester and an elastomeric polyurethane. Once the filaments are formed (spun) they are aged and only then are they stretched across the post-spinning country to develop curls. The required aging and the stretch step after spinning introduce additional time and cost into the manufacturing process.

The United States patent of North America No. 4,405,686, issued to Kuroda et al., Discloses a highly stretchable curly elastic filament that results from the combination of biconjugate of an elastomer and a non-elastomer having specific cross-sectional shapes (for example, bilobal). The stretching capabilities of the filaments in the filament are described as having two states: a low elongation stat in which the stretch due to the dominant ripple and a high elongation state where e stretch due to the elastomer is dominant. Like Chamberlain, the spun filaments should be pulled in a subsequent pass in order to develop the ripple that dominates the stretch characteristics at low elongations. Again this separation of the steps increases the expense and time to produce the product.

There is then a need for a fiber composition that will produce self-healing fibers in the absence of a post-treatment step. Such fiber will have an extension while exhibiting high recovery properties. Such a fibr may be used to impart form-fitting attributes to incontinent garments (eg, diapers), hospital garments (gowns), body wrap dressings as well as personal garments, where strength is required compressive, as well as in personal garments such as underwear and the like.

It is a main object of the present invention to provide attenuated melted conjugate filaments having improved curl and extensibility properties if the need for a subsequent stretch tensioning step is required.

It is a further object of the present invention to provide a method for forming melted attenuated conjugate filaments which are wrapped immediately after melting attenuation to form a band q having an improved extensibility in the radial direction and a high degree of recovery.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of the embodiments of the invention, when taken in conjunction with the accompanying drawings and the appended claims.

SYNTHESIS OF THE INVENTION The objects of the present invention are achieved by providing a novel "class" of attenuated attenuating filaments and a method to produce it unlike conventional curled fibers, have exceptional extension and recovery attributes.

In a preferred embodiment a method for forming a filament generally comprises providing a first component which is a polyolefin selected from the group consisting of polypropylenes, polyethylenes, and copolymers of polypropylene and polyethylene, suitable for the process of bonding with spinning, and, providing a second component in the form of a block copolymer thermoplastic elastomer ss > ® polyurethane, such as the Kraton or Arnitel polymers or mixtures thereof. Each of the components are extruded separately and combined in a bundle of conjugated yarn are passed through a spinning organ to form the melted side-by-side conjugated filaments. The filaments are attenuated according to conventional techniques using either the mechanical pull or suction forces to produce the conjugate filaments arranged side by side which develop spontaneously by approximately 25 or millimeters per inch after elongation of the attenuation force .

A side-by-side conjugate configuration of a polyolefin of type bound with spinning and a mixture of polymers ® ® Kraton (for example containing 70-100% Kraton 1659) or 10 ® Arnitel thermoplastic elastomer (eg EM 400) produced an extremely curly filament exhibiting a high degree of recovery after stretching. The ripple is helical in structure and occurs at a frequency of at least about 25 crimps per inch, and is typically 50-2 crimps per inch. The polymer composition and the spinning conditions that favor the development of spontaneous riza are: (1) the polyolefin component is suitable for spinning applications, meaning that the molecular weight distribution is narrow (for example Mw / Mn -3.0) -4.0) and has similar melt flow values (@ 230 ° C (for example in the range of approximately 20-100 grams / 1 minute) Examples of such polyolefins are Exxon 3445 polypropylene and Dow linear low density polyethylene. ASPUN 6811A. (2) The elastomeric component comprises about 25 80% of the filament. (3) The filaments are extruded co-melted through the spinning organ at 0.7-1 conditions. grams per hole per minute ("GHM") and the melted filaments are attenuated through the capture speeds of 700-250 meters per minute ("MPM").

These conjugated filaments extend to 200% of their relaxed length at low stress levels and recover almost completely with little induced settlement. elongations over 200% the filaments incrementally exhibit stretching force and retroactive recovery attributes This stretching behavior is attributed to the development of extremely high curls (allowing superior extensions) and the elastomeric component (favoring retraction and curling retention). This curling did not occur in the comparable tests with polyurethanes used as the elastomeric component. Additionally, these elastic and curled filaments have aesthetically pleasing touch characteristics. Ripple and polypropylene (or polyethylene) decrease the rubber-like feel typical of elastomeric filaments.

The present invention provides a continuous seamless elastic band made of high-density filaments through a one-step process, for example directly from the step of melting attenuation. These stretchable and conformable body structures are closely related to the tubular shape of the woven fabrics that resemble elastic wrist bands or woven fabrics in tubular form than the flat elastic nonwoven laminates. fabrication of the seamless web structures exhibiting excellent body shaping attributes are achieved by wrapping the attenuated filaments with spin-melt as described above about 1 rotating cylinder which controls the take-up speed. When the band of wrapped filaments is removed from the cylinder its length is contracted to a relaxed state by 60-80% (depending on the spinning conditions).

These band structures exhibit the same extension and recovery attributes as the individual filaments. There is a tendency for these crimped filaments to be made in bundles within a yarn-like structure that imparts a degree of structural integrity to the band so that it can be stretched repeatedly without separating individual filaments.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in the drawings in which like reference characters designate the same or similar part through the figures in which: Figure 1 shows a schematic drawing of melting attenuation apparatus with a suction device to immediately relax the attenuation forces Figure 2 shows a schematic drawing of band forming apparatus.

DETAILED DESCRIPTION As used herein, the term "conjugated fibers" refers to fibers which have been formed from at least extruded polymers of separate extruders but combined together to form a fiber.The conjugated fibers are also sometimes referred to as multicomponent fibers or The polymers are usually different from one another, even though the conjugated fibers may be single-component fibers The polymers are arranged in different zones arranged essentially constant across the cross-section of the conjugated fibers and extend continuously along the length of the fiber. length of the conjugate fibers The configuration of such a conjugate fiber can be, for example a sheath / core arrangement, where one polymer is surrounded by another or can be a side-by-side arrangement or an "islands in the sea" arrangement. The conjugated fibers are taught in US Pat. No. 5,108.82 issued to Kaneko et al. in U.S. Pat. No. 4,795,668 issued to Krueger, and in U.S. Patent 5,336,552 to Strack et al. Conjugated fibers are also taught in U.S. Patent No. 5,382,400 issued to Pike others and can be used to produce curling in the filaments by using different rates of extension and d contraction of two (or more) polymers. The crimped fibers can also be produced by mechanical means and through the process of the German patent DT 25 13 251 Al. For the bicomponent fibers, the polymers can be present in the proportions of 75/25, 50/50 / 75 or in any other desired proportions. The fibers may also have the forms as those described in U.S. Patent No. 5,277,976 issued to Hogle et al., U.S. Patent No. 5,466.41 to Hills and the patents of the United States of America. United States of North America Nos. 5,069,970 and 5,057,368 issued to Largman otors which describe fibers with non-conventional forms. As used herein the term "mixture" means a combination of two or more polymers.

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 North America. Bornslaeger.

As used herein, the terms "elastic" "elastomeric" when referring to a filament, film or tel means a material which with the application of a pressing force, is stretchable to a pressed length and stretches which is at least less than about 150% or one and a half times, its length not stretched and relaxed, and which s will recover at least 50% of its elongation with the release of the pressing and stretching force.

As used herein, the term "recover" refers to a contraction of a stretched material with the termination of a pressing force after stretching of the material by the application of the pressing force. For example, if the material having a relaxed unpressured length of 1 inch was stretched 50% by stretching a length of 1 and a half inches, the material will have had a stretch length that is 150% of its relaxed length if this material stretch of example contracted, that is to recover to a length of one and a tenth of an inch after the release of the pressing and stretching force, the material would have recovered 80% (0.4 inches) of its elongation Generally described, the present invention provides a method for forming a conjugate filament of lad by side from a first component and a second component by melting each component, combining them to form melted filaments each with a side and side configuration. then attenuate the melted filaments to solidify these. Self-hardening of the filaments occurs with the relaxation of the attenuation force.

The first component is a polyolefin. In a preferred embodiment polypropylene, polyethylene or copolymer of propylene and / or ethylene is employed. Preferred polypropylene is available as Exxo PD 3445 polypropylene (hereinafter sometimes referred to as "PP"), available from Exxon Chemical Company, of Houston, Texas. It was also found that by mixing the Exxon PD 3445 with a lower viscosity polypropylene typically shown for meltblowing applications, such as Montell PD 015 polypropylene (hereinafter referred to as "Montell PD 015") available from Montell Chemical, from Limington, Delaware, where Exxon P 3445 was present in the range of approximately 50-100%, more preferably approximately 66%, an acceptable mixture was provided. It was found that 100% of Exxon PD 344 provided a superior quality result than using polypropylene resin mixes of narrow molecular weight distributions with lower melt viscosities, eg, MF (at 230 ° C) is higher of around 35 grams / minutes. It will be understood, however, that for certain purposes such a mixture may be employed. Where a copolymer of proprylene and ethylene is used, the ethylene content is present in the concentration of about 7% or less, and about 93% or more of propylene.

The second component is a thermoplastic elastomer polymer made of block copolymers such as copolyesters, block copolymers of polyether polyamide block copolymers having the general formula ABA 'or A as copoly (styrene / ethylene-butylene), styrene-poly (ethylene propylene) ) -styrene, styrene-poly (ethylene-butylene-styrene) polystyrene / poly (ethylene-butylene) / polystyrene poly (styrene / ethylene-butylene / styrene) and similar Optionally, a flow modifier, as described below, can used to adjust the viscosity when combined with low viscosity polyolefins.

Useful thermoplastic elastomer polymers include block copolymers having the general formula BA 'or AB, wherein A and A' are each a polymer end block which contains a styrenic moiety such as poly (vinyl arene) and wherein B is an elastomeric polymer block means such as a conjugated diene or a lower alkene polymer. The block copolymers of type A-B-A 'may have the same or different thermoplastic block polymers for blocks A and A', and the block copolymers present are intended to span the branched and radial linear block copolymers. In this regard, the radial block copolymers can be designated (A-B) m-X, wherein X is a polyfunctional ato or a molecule and in which each (A-B) m-radiate of X X in a manner that A is an end block. In the radial block copolymer, X can be an organic or inorganic polyfunctional molecule or atom and m is an integer having the same value as the functional group originally present in X. This is usually from at least 3, and is frequently from 4. or 5 but it is not limited to this. Therefore, in the present invention the term "block copolymer" and particularly block copolymer "ABA '" and "AB" is intended to encompass all block copolymers having rubberized blocks and thermoplastic blocks as discussed above, which they can be extruded (for example in filaments) and without limitation in quantum to the number of blocks. Commercial examples of elastomeric copolymers are those known as materiale ® Kraton which are available from Shell Chemical Compan ® of Houston, Texas. Kraton block copolymers are available in several different formulas, a number of which are identified in US Pat. Nos. 4,663,220 and 5,304,599, incorporated herein by reference.

Polymers composed of an elastomeric tetrablock copolymer A-B-A-B may also be used in the practice of this invention. Such polymers are discussed in U.S. Patent No. 5,332.61 issued to Taylor et al., In such polymers, A is a block of thermoplastic polymer and B is a monomer unit of isoprene hydrogenated to a monomer unit. poly (ethylene-propylene essentially) An example of such tetrablock copolymer is styrene-poly (ethylene-propylene) -styrene poly (ethylene-propylene) copolymer or SEPSEP, available from Shell Chemica Company, of Houston, Texas, under the designation of comerci ® Kraton G-1659.

Another suitable material is an amide copolymer of polyester block having the formula: HO- [- C - PA - C - O - PE - 0] n - H wherein n is a positive integer, PA represents a polyamide polymer segment and PE represents a polyether polymer segment. In particular, the polyether block amide copolymer has a melting point of from about 150 ° C to about 170 ° C, as measured in accordance with ASTM D 789; a melt index of from about 6 grams per 1 minutes to about 25 grams per 10 minutes, as measured according to AST D-1238, condition Q (235 C / lKg load), a modulus of elasticity in flexion of from about 20 Mpa to 200 Mpa alreddo, as measured in accordance with ASTM D-790; a tensile strength at break from about 2 Mpa to about 33 Mpa as measured in accordance with ASTM D-638 norm and a final elongation at break from about 500% to about 700% as measured by ASTM D 638. A particular incorporation of the polyether block amide copolymer has a melting point of about 152 ° C as measured in accordance with ASTM D-789; a melt index of about 7 grams per 10 minutes, as measured in accordance with ASTM D-1238, Condition Q (235 C / l kilogram load); a modulus of elasticity in flexion of about 29.50 Mpa, as measured in accordance with ASTM D-790; a breaking tensile strength of about 29 Mpa a measure in accordance with ASTM D-639; and an elongation to break of around 650% as measured in accordance with ASTM D-638. Such materials are available in various class ® under the trade designation PEBAX from Atochem, Inc., Polymer ® Division (RILSAN), of Glen Rock, New Jersey. Examples of use of such polymers can be found in U.S. Patent Nos. 4,724,184, 4,820,572 4,923,742, incorporated herein by references given to Killia et al, and assigned to the same assignee of the present invention.

A preferred elastomer was mixed from Kraton 1659 and Quantum NA-601-04 LDPE (low density polyethylene, used herein as a processing aid for flow adjustment), available from Quantum Chemical of Cincinnati, Ohio. A ® ® preferred ratio was 70% Kraton 1659 and 30% Quantum NA-601-04. The usable range was approximately 50-100% d ® Kraton 1659.

The thermoplastic copolyester elastomers can be used in the practice of the invention. The copolyester d elastomers of thermoplastic block include the copolyte esters having a general formula: 0 0 0 0 0 fl QD H- ([0-G-0-C-C6H4-C] b- [O- (CH2) a-0-C-C6H4-C] m) nO- (CH2) a- OH wherein "G" is selected from the group consisting of poly (oxyethylene) -alpha, omega-diol, poly (oxypropylene) -alpha, omega-diol, poly (oxytetramethylene) -alpha, omega-diol and "a" "b "are positive integers including 2, 4 and 6," m "and" n "or positive integers including 1-20. Such materials generally have an elongation at break of from about 600% to 750% when measured in accordance with ASTM D-638 and melting point of from about 176 ° C to about 205 ° C when measured from in accordance with ASTM D-2117.

Commercial examples of such copolyester materials are, for example, those known com ® copolyether ester Amitel, formerly available from Akz Plastics from Arnhem, Holland and now available from DSM d ® Sittard, Holland, or those known as Hytrel which are available from E.l. duPont de Nemours of Wilmington Delaware. The formation of an elastomeric non-woven fabric of polyester materials is described, for example, in the patent of the United States of America No. 4,741,949 issued Morman and others and in the United States patent d North America No. 4,707,398 granted to Boggs, incorporated herein by reference. However, the mixture of copolyether ester d ® Arnitel was found to give less curl per inch than the ® Kraton / Quantum polyethylene mixture NA-601-04 LPDE. An optimal concentration of around 70% copolyether this one ® Arnitel in combination with 30% polyolefin component of the highest ripple, while 80% content of copolyte ® Arnitel ester was the maximum obtained with markedly less rust than with 70% Arnitel ester copolyether. The 100% d ® filaments of Arnitel ester copolyether did not exhibit ripple.

It was found that the polyurethanes substituted by the elastomeric component and attenuated in filaments and combination with polypropylene or polyethylene did not spontaneously ripple and were unusable in the present invention.

The process of melting attenuation where the melted filaments are attenuated while these solidify is known to those with ordinary skill and art and a detailed discussion is unnecessary. U.S. Patent No. 3,849,241 presents a detailed description of a melt attenuation process and is incorporated herein by reference. Briefly, the first and second polymer components are separately melted separately fed through the dosing pumps and combined into a conjugate spin package arrangement which includes a spinner member having a capillary vessel arrangement. The filaments formed are in a melted state when they leave the spinning organ. The melted filaments formed can be attenuated by suction or by mechanical pulling means, known to those skilled in the art. In the examples of the present invention the filaments formed were attenuated through a Lurgi pistol (see US Pat. No. 3,502,763 and 3,542,615 issued to Hartman) or other aspiration device, known to those skilled in the art depending on of the composition of the filaments and denies desired and attenuated preferably by wrapping the filaments around a cylinder by rotating at speeds of approximately 400-2500 MPM.

Preferably the proportions of the final filament attenuation rate, measured in meters / minute, at the rate of extrusion through the spinning organ, measured in grams / hole / minute, of at least 1100. The filaments formed at these proportions are approximately 3-6 deniers The relaxation of the tension after the pull of the melted filaments is essential to develop curly. Figure 1 shows a method for the attenuation of the melted filaments allowing the relaxation of the attenuation forces so that there is a minimum tension on the filaments.

The thermal test of the unstressed filaments in the filament form showed very little or no decrease in ripple to about 55 ° C.

In order to make the bands of the present invention, the filaments were wrapped around the take-up device, such as a cylinder or rotating roller held at one end of the shaft, as shown in FIG. 2 Removing the wrapper, either by stopping the roller takes preventing it from turning or by pushing the band out of rotating cylinder, resulted in a continuous ban type structure that contracted as soon as it was removed from the intake rod. This represents a contraction of at least about 60% of the circumference wrapped as it was originally wound around the pickup device. (This is the my contraction that occurs in the attenuated filaments melted after the relaxation of the attenuation forces). It's structure stretches and recovers radially. The circumference of the pick roller is a significant factor in determining the band size; depending on the size of the take-up roll the resulting band can be used to form cuffs, sleeves, legs, waistbands, and the like.

The point attachment of the web to impart greater integrity can be achieved by any of several techniques known to those skilled in the art. Such techniques include but are not limited to ultrasonic and adhesive thermal bonding. It is easy to do this before removing the cylinder band.

An important aspect of the present invention is that the novel combination of the init components produces a filament that is autorized. It is also important that this ripple occurs during the filament formation process, when the force and attenuation is released. The spontaneous riza exhibited by the present invention occurs within about 1 minute after the release of the attenuation force. The curled filaments of the prior art, for example those of Chamberlan and Kuroda, require a separate post-attenuation treatment and / or a step of aging, or a minimum, period of time subsequent to filament formation. Many of the available crimped fibers use media mechanical to introduce the ripple. The present invention does not require a separate aging step, but instead produces self-hardening fibr which exhibits high rip density, helical ripples, and improved stretch and recovery characteristics on the filaments of the prior art.

An advantageous feature of having the filaments in a continuous band form is that the accumulated retraction forces of the individual filaments incrementally resist extension to the "co winding" length (equal to the circumference of the take-up cylinder).

This mimics the strength stretch properties typically found with Lycra and other filaments made of 100% elastomeric components.

A further advantage is that the filaments produced by the present invention show thermally unstable potential to non-wovens containing a similar polyolefin component. This ability is important in relation to the filaments in a finished product since such product usually contains other components made of polyolefins eliminates the need and cost of applying an adhesive The invention will be further described in relation to the following examples, which are set forth for the purposes of illustration only. The parts and percentages that appear in such examples are by weight unless stipulated otherwise.

EXAMPLES EXAMPLE 1 This example used two extruders connected to a conjugate spinning wrapping arrangement side by side with polypropylene as the first component and the second component consisting of an elastomeric blend made of 70% Kraton 1659 + 30% of NA-601-04 LDPE from Quantum Chemical, added low density polyethylene for flow modification. (The ® subsequent references to Kraton mixtures in these examples refer to this mixture). Polypropylene (PP mix) had a low viscosity and consisted of a blend of approximately 66% of Exxon's PD 3445 (suitable for spun bonding applications) and 33% of Montell PF 015 (appropriate for melt blowing application) . At 1.25 GHM, the filaments were attenuated with melted at a proportion of component d® polypropylene 65% / mixture of 35% Kraton. The extremely high curl filaments resulted when they were pulled through a suction device used to attenuate with melt spinning filaments (such as a Lurgi gun device). The attenuated filaments with melted PSI pistol pressures of 100-170, which imparted solidified filament velocity of approximately 2000-2900 MPM, were put into bundles within a filament that exhibited unusual stretching and recovery attributes. The curl for this blend of Kraton and the polypropylene side-by-side filaments was distinctly different from that obtained with similarly arranged polyethylene and polypropylene components. The helical ripple was much tighter than any previously observed for a purely attenuated melted filament, with or without subsequent pulling steps.

The measurements conducted on this filament structure gave the following values: Bundle of filament = 11-14 filaments Curl frequency = 60-70 crimps / inch Filament diameter = 25-28 microns Peak load = 21.3 gm Peak elongation = 1146% Prior to these conjugate filaments, the highest rizad formed spontaneously in the co-attached filaments was 20 crimps / inch, with more typical values of 5-10 crimps / inch (for polypropylene / polyethylene conjugated filaments in a side arrangement) per side od asymmetrically cooled polypropylene). The pic elongations for the polypropylene filaments or the polypropylene / polyethylene side-by-side of a similar diameter were 150 300%. Therefore, the higher peak elongation value reasoned that it was a consequence of the linear shrinkage of the filaments due to the formation of the high ripple.

Table 1 Compares the representative filaments of the invention that were attenuated with melt using co-bonding techniques (high velocity air to impart melting attenuation forces and higher thin filament velocities) to other typical side-by-side conjugate filaments, processed in the same way.

Table 1 The Ripple for the Filaments Made with the Methods of United Melt Attenuation with Yarn for Side-Side Filaments with Non-Elastic Components: Filament speed Component Component% Maximum Total Fiber Curled A B A / B GHM (MPM) Inch PP polypropylene with 4% Ti02 50/50 0.7 2040 15 PP Polyethylene 50/50 0.7 2040 7 +/- 1 PP PE 50/50 0.7 3180 15 +/- 3 For the Present Invention: Mix Kraton Mix PP 35/65 1.25 2900 65 +/- 5 EXAMPLE 2 For this and the subsequent examples, the tests were carried out using a spinning / conjugate extrusion packing equipment to form the melted filaments and the mechanical take-up device to impart the attenuation of the melted filaments. The spinning / conjugate extrusion packing kit consisted of: 2 1.25 inch diameter extruders each with L / D = 24 / Round hole spinning bag side by side Spinning packages having 108, 144 or 260 capillary blood vessels po Yarn packing Extrusion / very hot temperatures = 400-420 ° F Cooling air cross flow rate = -60 FPM Component Description; The (second) elastomeric ® component of Kraton blend was 70% Kraton 1659 + 30% NA-601-04 LDP Quantum (mixed and pelitized through a twin screw pelitization system). Mixtures of polypropylene and low viscosity polypropylene, prepared in a twin screw pelitizer system, were used as the other (first component) These polypropylenes were Exxon PD 3445 ("PP") blends made of Exxon PD 3445 and Montell PF 015 to provide 66/33 ("PP2") and 50/50 ("PPl"). A verification of the position of the components in the non-attenuated filaments through the cross-sectional analysis showed that all the polypropylene components have been wrapped around ® Kraton blend component.This means that the d ® Kraton mixture had a viscosity higher than that of polypropylenes Spontaneous Curl Development; These conjugate filaments were attenuated with melt by forming a single wrap of the spin yarns around the rotating cylinder of the mechanical device and deflecting them with a suction device into a collection vessel. This method immediately relaxes the attenuation forces imparted by the mechanical pick-up device on the filaments. These filaments exhibited the same high degree of curl as the crimped filaments made in Example 1. The different velocities were used in two productions to determine how these factors influence curling. A qualitative evaluation of the ripple resulting from the various conditions is given in Table 2: Table 2 Mixed Melted-Yarn Mixtures of 40% ® Kraton and 60% PP 2 (66% of Exxon PD 3445 + 33% of Montel PF 015) GHM Sponge Shot MPM Spontaneous 1. 3 1000 low 1.3 1500 high 1.3 2000 very high 1.0 1200 moderate 1.0 1500 high 1.0 2000 very high The same method of melting attenuation with a mechanical pickup device followed by an immediate relaxation of those attenuation forces was used with 100% d Exxon PD 3445 as the polypropylene component (to the same proportion of component) gave rip to all the conditions mentioned above. The curling values of these aspirated filaments were subsequently measured to vary from 20 to 4 crimps / inch.

EXAMPLE 3 ® Elastic Band Formation with Kraton ~ co Mixtures Elastomer Component The filaments of the present invention using Kraton blends as the elastomeric component in combination with the polypropylene or polyethylene components will be allowed to form multiple wrappers on the take-up device in the following manner in order to make a seamless strip. A take-up roller with a circumference of 76 centimeters was used. The roller was held at one end of the shaft leaving the opposite end open so that the strip could be removed from the roller. The cylinder was operated on a speed range d of 444-2500 MPM and the conjugated filaments of the do components were extruded over a range of 0.75-1.3 GHM as specified in Table 3.

Removing the band by stopping the intake device and sliding the band out of the "open" end of the cylinder resulted in shrinkage of the wrapped filaments. The extension of the contraction is shown in Table 3. The radial contraction of the band is caused by the curling of the filaments. A simplified scenario for making such tube or band type structures is shown in Figure 2.

EXAMPLE 4 ® Elastic Band Formation with Arnitßl ~ EM 400 as e Elastomer Component ® ® The Arnitel EM 400 (Arnitel) s ® polyether ester was replaced by the Kraton in Example 6 for the elastomeric component in the conjugate filaments in the same ® proportions as those of the Kraton blend component and melted with attenuation at feed rates and com productions are set forth in Table 3.

Table 3 Band Curl and Shrinkage with Elastomeric Components Without Polyurethane Speed% of Total Curled / Shrinkage Sample GHM MPM Band Inch EXAMPLE 3: ® 40% Kraton mix / 60% PP 1 .3 800 29 + 5 Not measured 1..3 2000 47 + 10 Not measured 1, .0 1500 27 + 5 Not measured 1..0 2000 47 + 15 No measured 50% Kraton® blend / 50% PP 1. .3 2000 131 + 54 Not measured 70% Kraton® mix / 30% PP 1..3 2500 167 + 18 79 80% Kraton mix / 20% PP 1, .3 2000 119 + 24 Not measured ® 70% Kraton mix / 30% PP 0. .75 444 34+ 0 Not measured 0..75 900 116 + 24 71 0..75 1500 190 + 41 73 0, .75 2000 207 + 23 74 • ® 80% Kraton mix / 20% PP 0. .75 2000 226 + 31 79 ® 70% Kraton mixture / 30% PE 0. .75 1200 40 + 12 67 EXAMPLE 4: ® 70% Arnitel / 30% PP 1, .3 1000 0 + 0 0 1, .3 1500 18 + 5 77 1. .3 2000 20 + 2 74 55% Arnitel / 45% PP 1. .3 1500 12 + 3 79 1, .3 2000 31 + 8 77 1, .3 1500 35 + 6 74 70% Arnitel / 30% PP 0. .75 700 17 + 14 30 0. .75 1000 31 + 6 61 0. .75 1500 50 + 10 66 0. .75 2000 59 + 6 71 0. .75 2500 68 + 11 70 ® 50% Arnitel / 50% PE 0.75 2500 65 + 7 75 ® 70% Arnitel / 30% PE 0.75 1500 8 + 4 19 0.75 2000 47 + 9 70 0.75 2500 59 + 19 75 ® 80% Arnitel / 20% PE 0.75 2000 20 + 2 48 0.75 2500 45 +14 75 [Mix of Kraton®. . ^ 0 means a mixture of 70% by weight d ® Kraton 1659 and 30% by weight of Quantum NA-601-04] Examples 5-9 involve conjugated polymer combinations that are more typical of autocratizing filaments, conjugated copolymers wherein a component is a polyurethane, or elastomeric polymer monocomponent filaments. The filaments of these polymers do not produce the same filament curl and / or contraction as the invention.

EXAMPLE 5 Lack of Curl with 20 Polypropylene Melt Flow To determine the sensitivity of the developed development due to the type of polypropylene, a kind of melt flow fiber 20 (Shell 5E38) was substituted by the low viscosity polypropylenes and combined with the mixture d ® Kraton. A maximum pulling speed of 1250 MPM was obtained 0.75 GHM for proportions of 40/60 and 30/70 of the mixture d ® Kraton and melt flow polypropylene components 2 respectively. No curling was developed for this filaments using the melting attenuation method followed by the immediate relaxation of the attenuation forces. L Table 4 establishes the curling and melting d melt results. The viscosity of the melt flow polypropylene 20 was higher than that of the Kraton® mixture as shown in the photomicrographs in cross-section where the component d® mixture of Kraton polypropylene wrapped around the 20 MF polypropylene component.

EXAMPLE 6 Polypropylene Filaments Autorrizantes Self-hardening polypropylene filaments were made from dissimilar classes using the same configuration side by side. The polypropylene components were the melt flow resin 20 and the PP or PP 1 polypropylene blends (50/50 or 66/33 from Exxon PD 3445 and Montell PF 01 respectively). At a component ratio of 50/50 transverse flow cooling airs above 1.3 GHM, and a pull speed of 1500 MPM, curling after melting attenuation and immediate relaxation was insignificant compared to that of the filaments d ® low viscosity polypropylene / Kraton mixture of the invention. The melting attenuation of the filaments with polypropylene component of 20 MF above 1700 MPM found breaks in the spinning line. Table 4 lists this melting attenuation conditions and the resulting low ripple.

Table 4 Filaments of Melted-Spin Conjugate of Other Components Total Composition Curled / Filament Grade GHM MPM Inch EXAMPLE 5: ® 40% Kraton / 60% 20 MF PP 0.75 1250 0 ® 30% Kraton / 70% 20 MF PP 0.75 1250 0 EXAMPLE 6: 50% 20 MF PP / 50% PPl 1.3 1500 50% 20 MF PP / 50% PP2 1.3 1500 < 7 (PP 1 &2 = 50/50 &66/33 mix of PD 3445 and PF 01 respectively) EXAMPLE 7 Filaments of 100% Elastomeric Component The filaments made of 100% mix d ® ® ® Kraton, Arnitel or polyurethane elastomers (Pellethane) were melted and attenuated and formed into bands according to the method described in Example 4. Table 5 specifies melting attenuation conditions and lists the lack of curl development for these elastomers The shrinkage of the filaments in the band form was less than that measured for the filaments of the invention when made at comparable melt attenuation conditions.

Table 5 Band and Curl Contraction with Elastomeric Component Velocity% of Total of Curly Shots / Contrac¬ Sample GHM MPM Pulqadation ® A. Pellethane Polyurethane 0.75 1000 0 3 0.75 2000 0 34 ® B. 100% Kraton blend 0.85 435 0 Not measured ® C. 100% Arnitel 0.75 2500 0 19 The melt attenuation filaments of 100 Kraton polypropylene blend found a maximum drawn speed of 435 MPM at 0.85 GHM. Higher jalad speeds resulted in an increased number of filament breaks on the spinning line. The use of the Arnitel elastomer produced spinning lines without filament breaks over the range of melt attenuation conditions tested (for example 2500 MPM maximum).

The filaments of 100% polyurethane ® (Pellethane), spun at 1000 and 2000 MPM, did not show rippled elastomeric attributes. Fulfilling the needs of aging the TPU, the attributes of recoverable stretch developed over time.

EXAMPLE 8 Conjugated Filaments Using Non-Elastomeric Components The non-elastic web structures were made of polypropylene (Exxon PD 3445) and polyethylene (Aspun 6811 of Dow) conjugated filaments at various proportions of components and rates of intake. Samples were made at a polypropylene content of 30%, 50% and 70% and over a range of tap speeds of 700 to 2000 MPM. The curl formed spontaneously in these filaments was essentially less than that observed with the use of the elastomeric component. Curly May -6 curled / inch, occurred at a pulling speed of 700 MPM and decreased with increasing speed (with < curled / inch at 2000 MPM). Table 6 shows values for the curl and band contraction.

Table 6 Curl and Band Shrinkage for Polypropylene and Polyethylene Filaments Speed, "O of Total Shot Curled / Contracted- Shows GHM MPM Pulated % PP / 70% PE 0.75 1000 6 + 0.3 42 0.75 1500 3 +0.2 8 50% PP / 50% PE 0, .75 700 5 + 0 .2 0 0 .75 1000 6 + 0 .4 61 0, .75 1500 5 + 0. .1 21 0. .75 2000 22 ++ 00 .. .55 -5 (expand) 70% PP / 30% PE 0.75 700 5 + 0.3 48 0.75 1000 4 + 0.5 48 0.75 1500 2 + 0.2 2 0.75 2000 1 + 0.1 -5 (exp.

EXAMPLE 9 Conjugated Filaments Made Using Polyurethane as an Elastomeric Component This example evaluated the polyurethanes (TPU) for elastomeric component in combination with the polypropylene and polyethylene components. A production of 0.75 GHM maintained for all samples. A polyurethane (58887 B.F. Goodrich) was used as the elastomer component and the melted attenuated in filaments in combination with polypropylene. They did not find spinning problems at a polyurethane content 70% or 80% and at shooting speeds of 1200 and 2000 MP These conjugated filaments did not curl or contract as they were removed from the pick roller. Substituting polyethile ® Aspun 6811 for the polypropylene component also did not give ripple development. This lack of curling and elastic attribution was observed in the filaments of a combination ® component of 70% tin polyurethane 58213/30% melted polyethylene attenuated at 2000 MPM. These same deficiencies were also found for the components ® 50% and 70% of the Pellethane 2103-80PF from Dow (polyurethane L 105) in combination with any type of spun polyolefin 1000 and 2000 MPM. Table 7 lists the conditions of melting attenuation and provides the results of ripple and shrinkage for these conjugate filaments. that cover the structures described here as carrying out the recited function and not only the structural equivalents without also the structures and equivalents. Therefore even when a nail and a screw may not be structural equivalent in the sense that a nail employs a cylindrical surface to secure wooden parts together, while a screw employs a helical surface, in the environment of the parts of the fastening wood, a screw and a nail can be equivalent structure.

It should be further noted that any patents, applications or publications mentioned herein are incorporated by reference in their entirety.

Claims (20)

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

1. A method for forming a filament having improved elastic properties, comprising the steps of: a) providing a first component comprising a polyolefin; b) providing a second component comprising a thermoplastic urethane elastomer; c) melting said first component to form a first melted resin; d) melting said second component to form a second melted resin; e) transporting said melted resins to a spinning organ; f) commingling said components first and second to form the conjugate filaments side by side and attenuate said filaments while still in a melted state and allow said filaments to solidify; and g) releasing said attenuating forces as a pair to allow said filaments to autorrize and contract.

2. The method, as claimed in clause 1, characterized in that said first component is selected from the group consisting of polypropylene, polyethylene, copolymers of propylene and ethylene.

3. The method, as claimed in clause 1, characterized in that said first component has a narrow molecular weight distribution of approximately d 3.0-4.0 (Mw / Mn).

4. The method, as claimed in clause 1, characterized in that the second component e is selected from the group consisting of copol esters, polyether polyamide block copolymers, block copolymers having the general formula ABA 'or AB com copoli (styrene / ethylene-butylene), styrene-poly (ethylene-propylene) -styrene, styrene-poly (ethylene-butylene) -styrene, polystyrene / poly (ethylene-butylene) / polystyrene, poly (styrene / ethylene-butylene / styrene).

5. The method, as claimed in clause 1, characterized in that said second component is a block copolymer having the general formula ABA ', where A and A' are each a thermoplastic polymer end block which contains a styrenic moiety such as poly (vinyl arene) and wherein B is a middle block of elastomeric polymer.

6 The method, as claimed in clause 51, characterized in that said middle block of polymer is selected from the group consisting of a conjugated diene and d a lower alkene polymer.

7. The method, as claimed in clause 1, characterized in that said second component is ABAB tetrablock copolymer so that A is a thermoplastic polymer block and B is a isopren monomer unit hydrogenated to a poly monomer unit. (ethylene-propylene) substantially.

8. The method, as claimed in clause 1, characterized in that said second component is a polyester block amide copolymer having the formula: HO- [- C - PA - C - O - PE - 0] n - H Or O where n is a positive integer, PA represents a polyamide polymer segment and PE represents a polyether polymer segment.

9. The method, as claimed in clause 1, characterized in that the second component is a thermoplastic block copolyester elastomer having the general formula: O O O O [I D D O H- ([0-G-0-C-C6H4-C] b- [O- (CH2) a-0-C-C6H4 -C] m) n-O- (CH2) a-0H wherein "G" is selected from the group consisting of poly (oxyethylene) -alpha, omega-diol, poly (xipropylene) alpha, omega-diol, and poly (oxytetramethylene) -alpha, omega-diol and "ay" b " they are positive integers including 2, 4 and 6, "m" and "n" or positive integers including 1-20.

10. The method, as claimed in clause 1, characterized in that the percentage of the first component is approximately 20-75%.

11. The method, as claimed in clause 1, characterized in that the percentage of the second component is approximately 25-80%.

12. The method, as claimed in clause 1, characterized in that said filaments are formed at a rate of the final filament attenuation rate, measured in meters / minute, at the rate of extrusion through the spinner, measured in grams / hole / minute, of at least 1100.

13. The method, as claimed in clause 1, characterized in that said filaments formed of approximately 3-6 deniers.

14. The method, as claimed in clause 1, characterized in that said ripple is greater than about 25 crimps / inch.

15. The method, as claimed in clause 1, characterized in that said filaments shrink by about 60% or more after relaxation of the attenuation forces.

16. A method for forming a continuous band having elastic properties comprising the steps of: a) providing a first component comprising a polyolefin; b) providing a second component comprising a thermoplastic urethane elastomer; c) melting said first component to form a first melted resin; d) melting said second component to form a second melted resin; E) transporting said melted resins to a spinning organ; f) combining said first and second components to form the conjugated filaments of each side and attenuating said filaments while still in a melted state to allow said filaments to solidify 20 g) wrapping said filaments around a structure to form a band; Y h) removing said band from said support structure to release said forces from 25 attenuation as to allow said filaments to autorrize and contract.

17. The method, as claimed in clause 16, characterized in that it comprises the step of joining d point at least a part of said band.

18. The method, as claimed in clause 17, characterized in that the point junction e selected from the group consisting of thermal bonding, ultrasonic bonding, and adhesive bonding.

19. A band that has elastic properties that comprises: a) a first component comprising a polyolefin; b) a second component comprising a non-urethane thermoplastic elastomer; Y c) said first and second composite components combined to form self-conjugate filaments conjugated from side to side, said filament being wrapped around a supporting structure and removed from the support structure to form a band.

20. A continuous band having elastic properties formed by the process comprising the steps of: a) providing a first component comprising a polyolefin; b) providing a second component comprising a thermoplastic elastomer if urethane; c) melting said first component to form a first melted resin; d) melting said second component to form a second melted resin; e) transporting said melted resins to a spinning organ; f) combining said first and second components to form the conjugated filaments side by side and attenuating said filaments while still in a melted state and allowing said filaments to solidify; g) wrapping said filaments around a structure to form a band; Y h) removing said band from said support structure to release said d attenuation forces as to allow said filaments to autorrize and contract. • r 52 R E S U M E N Conjugated filaments side by side made of thermoplastic elastomers and polypropylenes of type 5 with spinning exhibit an extremely high propensity to autorrize. At appropriate polymer proportions and appropriate processing conditions (with aerodynamic or mechanical pulling) the ripple develops spontaneously after relaxation of the attenuating force. This amount of curly The degree of elastic properties will depend on elastomer content and processing conditions. The resulting rizad is typically in the range of 25-200 pound curls. This curly combination is exceptionally high of an elastomer component imparting properties 15 stretching and recovery. The filaments may wrap around a cylindrical support structure to create a continuous seamless elastic band, useful for articles in the body.