JP2005513279A - Fiber with high elongation and low denier formed by spinning with high extrusion ratio - Google Patents

Abstract

  Spinning a polymer composition through a small diameter capillary yields low denier, high stretch fibers, a soft extensible nonwoven web containing the fibers, and a disposable product containing the nonwoven web.

Description

  The present invention relates to a fiber having low denier and high extensibility, a soft non-woven web containing the fiber, and a disposable article containing the non-woven web.

  From nonwoven webs formed by non-woven extrusion methods such as meltblown and spunbond, products and product components can be made very inexpensively, so that the product is discarded only once or after several uses Can be a possible product. Representative of such products include absorbent disposable articles such as diapers, urinary incontinence pants, training pants, women's sanitary garments, wipes and the like.

There is a consumer need for soft extensible nonwovens for use in disposable products. The softer the nonwoven fabric, the gentler it is to the skin, which helps to add a feeling of underwear to the diaper. When a nonwoven fabric that can be stretched greatly with relatively little force is used as part of a stretched composite material, the fit can be maintained in products such as disposable diapers. The use of automatic post-processing is simplified. An extensible material means herein a material that is extensible but does not necessarily restore all or part of the applied tension. On the other hand, an elastic material, according to its definition, must be able to recover a significant portion of its stretched state after removing the applied force.
Several approaches have been used in the art to make extensible nonwovens.

  PCT International Publication No. WO 00/04215 discloses a unique bond pattern for producing nonwoven fabrics with high elongation, especially polypropylene short fibers with a core-sheath structure. This adhesive pattern has staggered adjacent sites so that the sites do not overlap in the longitudinal direction of the product. This site is rectangular in shape, and its area is preferably less than 20% of the total adhesion area. It is disclosed that since the fiber running in the direction inclined by 35 to 55 ° from the longitudinal direction is not bonded, the elongation rate in the lateral direction of the product becomes higher.

  Often fiber construction is used to obtain extensibility. In US Pat. Nos. 5,804,286 and 5,921,973, polyethylene and polypropylene are mixed in the presence and absence of a miscible ethylene-propylene copolymer to produce less fuzz and excellent extensibility. It is disclosed that a soft and strong non-woven fabric provided with PCT International Publication No. WO 00/31385 discloses mixing ethylene copolymers and polypropylene, and US Pat. No. 6,015,317 discloses mixing two ethylene polymers, both This is to improve adhesive strength and fiber extensibility while maintaining excellent spinning performance. U.S. Pat. No. 5,616,412 discloses a filament (2-4 denier / fiber) containing polypropylene and high molecular weight polystyrene, the elongation of which is only polypropylene. It is higher than the filament. U.S. Pat. No. 5,322,728 discloses a soft nonwoven fabric excellent in extensibility containing an ethylene copolymer, and U.S. Pat. No. 4,769,279 discloses a soft excellence excellent in extensibility containing an ethylene acrylic copolymer. A nonwoven fabric is disclosed. In U.S. Pat. Nos. 4,804,577 and 4,874,447, stretchable meltblown nonwovens comprising a mixture of a polyolefin and an elastomeric copolymer of isoolefin and conjugated diolefin such as isobutylene-isoprene copolymer are disclosed. It is disclosed. U.S. Pat. No. 5,349,016 discloses drawn fibers of grafted propylene polymers (e.g., styrene or methyl methacrylate grafted onto a polypropylene backbone), which material has high bend recovery and flexural elasticity. And in some cases has a higher elongation than the neat polypropylene control. U.S. Pat. No. 6,080,818 discloses fibers used in nonwoven fabrics composed of a mixture of isotactic polypropylene and atactic flexible polyolefin, the elongation of which is determined by the flexibility of the flexible polymer. It is higher than the non-woven fabric that is not included.

  All of these manufacturing methods can improve the extensibility of fibers having moderate to low levels of denier to some extent, but are less than those disclosed in the present invention. In addition, the above approach includes the step of mixing expensive materials, and special mixing methods may be required to ensure that the materials are properly dispersed within the mixture. .

  The method of forming the nonwoven web can be used to maximize stretch properties. U.S. Pat. No. 5,494,736 discloses a highly stretched lashed nonwoven fabric made from fibers with a high stretch rate, in which the fibers are oriented laterally rather than a conventional lashed fabric. It is arranged. The claimed adhesion area is 8-25%.

  There is still an unmet need in the industry for extensible nonwovens consisting of fibers with moderate to low levels of denier that can be produced from conventional resins without the use of expensive specialty or elastic polymers. It is well known that as the rate of spinning decay increases, the orientation of the molecules increases and the fiber elongation decreases. For strong fibers with low denier, the above is not a problem, but the production of fibers with high elongation and low denier is an important issue today. Accordingly, it is an object of the present invention to disclose a method for producing fibers with high elongation to break and low denier. It is a further object of the present invention to disclose a soft extensible nonwoven web comprising low denier and highly extensible fibers. It is a further object of the present invention to disclose a disposable article comprising a soft extensible nonwoven web.

  Disclosed is a means for producing fibers with high elongation to break and low denier. This combination of properties can be achieved by changing the design of the fiber spinneret to reduce the capillary diameter and maintain the desired spinning speed, but as a result of the conventional spinning process Compared to a high withdrawal ratio, the withdrawal ratio is moderate to low. In certain embodiments of the invention, the polymer composition is melt spun so that the draw ratio is less than 400, the discharge rate is 0.01 to 2.0 g / min / mouth, and the spinneret diameter is less than 200 microns. And fibers with a diameter in the range of 5-25 microns. In another embodiment of the present invention, by melt spinning the polymer composition such that the draw ratio is less than 400, the fiber elongation to break is greater than 400%, and the spinneret diameter is less than 200 microns. Includes fibers with diameters ranging from 5 to 25 microns that are manufactured.

  Without being bound by theory, it is believed that the reduction in the draw ratio results in the orientation of the fibers, thereby keeping the extensibility to break higher. Thereby, the fabric with high uniformity which consists of a fiber with a small diameter and high extensibility can be manufactured. Non-woven webs with this combination of properties can be incorporated into parts of articles that have excellent usability and overall performance thanks to their extensibility and flexibility, so they can be incorporated into diapers, incontinence pants, training It is particularly suitable for use in absorbent disposable articles such as pants for women, women's sanitary garments, wipes.

  As used herein, the term “absorbent article” refers to a product that absorbs and contains bodily discharges, and more specifically comes into contact with or is adjacent to the wearer's body. It refers to products that absorb and contain the various effluents that are released.

  As used herein, the term “disposable” means an absorbent article that is not intended to be laundered or restored or reused as an absorbent article (ie, discarded after a single use, preferably Is intended to be recycled and composted or treated in an environmentally sound manner). An “integrated” absorbent article refers to an absorbent product that combines separate parts to form an integrated shape that does not require a separate operating portion such as a holder or liner.

  As used herein, the term “nonwoven web” refers to a web having a single fiber or yarn structure that is interlaid but is neither regular nor repeatable. Nonwoven webs have heretofore been formed by various processing methods such as carding including air laying, melt blowing, spunbonding, and adhesive card web processing.

  As used herein, the term “fine fiber” refers to a fiber having an average diameter of about 100 microns or less and a length to diameter ratio of greater than about 10. A person skilled in the art will determine the overall flexibility and feel of the fiber, depending on the diameter of the fibers that make up the nonwoven web. In general, the lower the denier fiber, the higher the flexibility than the higher denier fiber. You will understand that we offer products that are sexual and touchable. In order to obtain adequate flexibility and feel, the diameter of the fibers of the present invention is preferably about 5 to 25 microns, more preferably about 10 to 25 microns, and even more preferably about 10 to 20 microns. The diameter of the fiber can be measured, for example, using an optical microscope with a 10 mm scale.

  As used herein, the term “meltblown fiber” refers to a high velocity gas (eg, air) stream of molten thermoplastic material as molten yarns or filaments through a plurality of fine, usually circular mold capillaries. It refers to a fiber whose diameter is reduced to a diameter of a microfiber by thinning a filament of a thermoplastic resin material melted by the gas flow and thinning the filament. The meltblown fibers are then moved by a high velocity gas stream and settled onto the collection surface to form a randomly dispersed web of meltblown fibers.

  As used herein, the term “spunbond fiber” refers to a melted thermoplastic material comprising a plurality of fine, usually circular, spinneret capillaries (with a diameter as long as the diameter of the extruded filament). Refers to small diameter fibers formed by extruding as a filament and then rapidly shrinking by drawing using a conventional godet winding system or air-pass drag damping device. If a godet system is used, the fiber diameter can be further reduced through stretching after extrusion.

  As used herein, the term “consolidation” or “consolidated” refers to bringing at least some of the fibers of a nonwoven web closer together to form one or more sites, This site functions to increase the resistance of the nonwoven to external forces such as wear and tension compared to an unconsolidated web. “Consolidated” can refer to the entire nonwoven web processed, such as by hot spot bonding, so that at least some of the fibers are closer together. Such a web can be considered a “consolidated web”. In another sense, certain individual areas of intimate fibers, such as a single thermal bonding site, can be described as “consolidated”.

  Consolidation can be achieved by methods of applying heat and / or pressure to the fiber web, such as heat spot (ie, point) bonding. Hot spot bonding can be achieved by passing the fiber web through a pressure nip formed by two rolls, one of which is heated to the aforementioned U.S. Pat. No. 3, issued to Hansen et al. It contains a plurality of raised points as described in 855,046 on its surface. Consolidation methods can include, but are not limited to, ultrasonic bonding, air passing bonding, resin bonding, and hydroentanglement. Hydroentanglement usually involves treating the fiber web with a high pressure water jet to consolidate the web by mechanical fiber entanglement (friction) in the area where consolidation is desired, forming sites in the fiber entanglement region. U.S. Pat. No. 4,021,284 issued to Kalwaites on May 3, 1977, and U.S. Pat. No. 4,024,612 issued to Contrator et al. On May 24, 1977 As shown, the fibers can be hydroentangled and the two documents are incorporated herein by reference.

  The nonwoven web of the present invention has a useful application as a component of an absorbent disposable article such as a diaper, but the application is not limited to an absorbent disposable article. The nonwoven webs of the present invention can also be used in applications that require flexibility and extensibility, or that benefit from flexibility and extensibility (wiping products, polishing cloths, furniture linings, durable garments, etc.). .

  The stretchable soft nonwoven fabric of the present invention may be in the form of a laminate. Laminates can be bonded by any number of bonding methods known to those skilled in the art, including thermal bonding, adhesive bonding (including spray adhesives, hot melt adhesives, latex based adhesives, etc. Non-limiting), sonic and ultrasonic bonding, bonding methods such as extrusion lamination where the polymer is poured directly onto another nonwoven and adhered to one side of the nonwoven while still in a partially molten state, or meltblown fiber nonwoven on the nonwoven The stacks can be bonded together by depositing on. These and other suitable methods of making laminates are described in US Pat. No. 6,013,151 issued to Wu et al. On January 11, 2000, and Morman et al. On August 3, 1999. U.S. Pat. No. 5,932,497, both of which are incorporated herein by reference.

  The term “polymer composition” as used herein generally includes homopolymers (blocks, grafts, copolymers such as random and alternating copolymers, terpolymers, etc.), and mixtures and modifications thereof. However, it is not limited to these. Further, unless otherwise indicated, the term “polymer composition” is intended to include any possible geometric configuration of the material. These configurations include, but are not limited to isotactic, syndiotactic, and random symmetries. Examples of thermoplastic polymers suitable for use in the present invention include polyethylene, polypropylene, polyethylene-polypropylene copolymers, polyvinyl alcohol, polyesters, nylon, polylactides, polyhydroxyalkanoates, aliphatic ester polycondensates. And mixtures thereof, but are not limited to these. Preferred polymer compositions include polyolefins such as polyethylene and polypropylene, or polyesters such as poly (ethylene terephthalate) and copolymers thereof. Preferred additional polyesters include poly (lactic acid) (such as Mitsui Chemical's Racea or Dow Cargill's EcoPLA), poly (caprolactone) (such as Union Carbide's Tone P787), poly (butylene succinate) (Showa Denko) Bionolle 1000 series, etc.), poly (ethylene succinate) (Japan catalyst Lunare SE, etc.), poly (butylene succinate adipate) (Showa Denko Bionolle 3000 series, etc.), poly (ethylene succinate adipate), fat Polyester-based polyurethanes (Morton Internationa's Morthane PN03-204, Morthane PN03-214, Morthane PN3429-100, etc.), adipic acid, terephthalic acid, and 1,4-butanediol copolyesters (from Eastman Chemical Company) Eastar Bio, BASF Ecoflex, etc.), polyester-amides (Bayer Corporation BAK series, etc.), hydrolyzable Aromatic / aliphatic copolyesters (such as DuPont Biomax), cellulose esters (such as cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate from Eastman Chemical Company), combinations and copolymers thereof, etc. However, it is not limited to these.

  The polymer composition may further comprise various non-polymeric components, among others, nucleating agents, antiblocking agents, antistatic agents, slip agents, heat promoting stabilizers, antioxidants, oxidation promoting additives, pigments, A filler etc. are mentioned. Usually, in order to advantageously combine flexibility and extensibility, it is not necessary to incorporate the aforementioned additives into the composition, but these additives can be used in conventional amounts.

  One skilled in the art will appreciate that the melt flow index of the polymer composition is suitable for the fiber manufacturing method of interest, such as melt spinning or meltblowing. The melt flow index of the polymer composition can be measured, for example, using the method outlined in ASTM D1238.

  As used herein, the term “extensible” means at least about 400% without significant problems when biasing force is applied, more preferably at least 600% without significant problems, more preferably Means a fiber that stretches at least 800% without causing significant problems. The elongation rate until breakage can be measured using, for example, the method outlined in ASTM D3822, and the length obtained by elongation before breakage is obtained by subtracting the distance between the marked lines at the beginning of the test. Divided by the distance between marked lines and multiplied by 100.

  Molded fibers such as long fibers, short fibers, hollow fibers, polygonal cross-section fibers, and multicomponent fibers can all be produced using the method of the present invention. As used herein, a component means a single part of a fiber that has a spatial relationship with another part of the fiber. Multicomponent fibers, generally bicomponent fibers, may be side-by-side, sheath-core, radial, ribbon, or sea-island shaped. The sheath may be continuous or discontinuous around the core. The fibers of the present invention may be of different shapes including circles, ellipses, stars, squares, and various other eccentricities. The fibers of the present invention may also be splittable fibers. Fission may be caused by rheological differences in the polymer, or may be caused by mechanical means and / or fluid induced deformation. As used herein, the diameter of a cross-sectional fiber that is not a circle is equivalent to the diameter of a circle having the same cross-sectional area.

  In the conventional melt spinning method, the fiber speed or the spinning speed is most commonly calculated by the following continuous equation.

式中、Ｖ_xは総繊維速度、Ｑは紡糸口金あたりの吐出量、ρ繊維質は繊維密度、ｄは繊維の直径（又は等価直径）である。総繊維速度は、２つの主な構成要素から構成されている。

Wherein, V _x is the total fiber speed, Q is the discharge amount per spinneret, [rho fibrous fiber density, d is the fiber diameter (or equivalent diameter). The total fiber speed is composed of two main components.

式中、Ｖ_oは紡糸口金からの繊維吐出速度であり、Ｖ_Aはフィラメントの減衰を伴う繊維の見かけ速度である。Ｖ_Aを決定する因子のうち最も重要なのは、慣性力、抵抗力、レオロジー的力である。Ｖ_Aの抵抗力は、フィラメント中の配向性を生み出すものである。

Where V _o is the fiber discharge rate from the spinneret and V _A is the apparent fiber velocity with filament attenuation. The most important factors that determine _VA are inertial force, resistance force, and rheological force. The resistance of V _A is what creates orientation in the filament.

  The fiber discharge speed is calculated by Equation 3 and changes only by Q and the capillary diameter (or equivalent diameter) D.

この場合、式中、密度ρメルトはポリマー溶融密度である。Ｑ、Ｄが唯一の変数であるため、繊維吐出速度は、毛細径のみによって変化する。

In this case, the density ρ melt is the polymer melt density. Since Q and D are the only variables, the fiber discharge speed varies only with the capillary diameter.

It has been well documented that increasing the fiber damping rate V _A increases the orientation within the fiber, and in the manufactured fiber, the diameter decreases and the strength increases but the elongation decreases. While not wishing to be bound by theory, fibers with high elongation can have a lower orientation in the fiber while maintaining a medium to small diameter to achieve excellent flexibility and feel. desired. That is, the damping speed V _A = V _x −V _o or the reduction ratio V _x / V _o must be lowered. In order to keep the fiber diameter small in order to obtain uniformity, coverage, and flexibility, it is customary to reduce the discharge rate Q. However, this reduces the total production amount of raw materials, and it is not possible to obtain an economically good effect. In general, one skilled in the art would consider the discharge rate of about 0.01 g / min / mouth to be very small. Moreover, if it is those skilled in the art, when it becomes larger than discharge amount about 2.0g / min / mouth, the flow of a mold will become unstable in terms of a melt fracture, the amount of slips with a wall, etc., and it has suitable quality. It will be understood that it becomes difficult to process and accumulate the product. Accordingly, the discharge rate is in the range of 0.01 to 2.0 g / min / mouth, more preferably in the range of 0.2 to 1.0 g / min / mouth, and still more preferably in the range of 0.6 to 0.8 g / min / mouth. The mouth area is preferred. The discharge amount per unit can be measured, for example, by accumulating extrudates for an arbitrary time, and then dividing the total accumulation value by the time interval at which the extrudate is accumulated and the number of spinnerets in which the filaments exit. it can.

The method of the present invention reduces the draw ratio V _x / V _o or the damping rate V _A by increasing the fiber velocity (V _o ) as it exits the spinneret capillaries without reducing the discharge rate. Can do. This can be achieved by using a small diameter capillary. The useful and unique number of spinning, which is the main part of the present disclosure, is calculated by the following formula.

引落比と同様に、紡糸数Ｓ_xも低い方が好ましい。

Similar to the draw ratio, it is preferable that the number of spinning S _x is also low.

Although not wanting to be bound by an example, for example, if an arbitrary discharge rate is 0.52 g / min / mouth (a typical amount in a conventional high-speed melt spinning system) and a standard capillary diameter is 0.6 mm, a melt spinning grade of The exit velocity V _o of the polypropylene filament is about 2.5 m / min. In general, in order to produce a highly uniform nonwoven in conventional high speed melt spinning system, the fiber velocity V _x at 2000 m / min, greater than must be activated system. Then, considering the properties associated with the fibers in this case (for example, high orientation and low elongation), the draw ratio V _x / V _o is about 800, and the number of spinning S _x is about 7980 microns / (g / min / Mouth). With similar spinning conditions and using a capillary diameter of 0.07 mm instead, the filament exit velocity increases to about 183 m / min, V _x / V _o decreases to about 11, and S _x is about 403 Decrease to micron / (g / min / mouth). The resulting fiber has lower orientation and higher extensibility.

A person skilled in the art will determine the flexibility and feel of the entire fiber depending on the diameter of the fibers constituting the nonwoven web, and the smaller the denier, the higher the flexibility than the larger denier. It will be understood that this results in a product with comfort. In order to obtain adequate flexibility and feel, the diameter of the fibers of the present invention is in the range of about 5-25 microns, more preferably in the range of about 10-25 microns, and even more preferably in the range of about 10-20 microns. Preferably there is. In order to maintain a small fiber diameter in order to obtain uniformity, coverage, and flexibility, it is customary to reduce the discharge rate Q. However, this reduces the total production amount of raw materials, and it is not possible to obtain an economically good effect. In general, one skilled in the art would consider the discharge rate of about 0.01 g / min / mouth to be very small. Moreover, if it is those skilled in the art, when it becomes larger than about 2.0 g / min / mouth, the flow of a mold will become unstable in terms of the amount of melt fracture or sliding with a wall, etc., and it has suitable quality. It will be understood that it becomes difficult to process and accumulate the product. Accordingly, the discharge amount is in the range of 0.01 to 2.0 g / min / mouth, more preferably in the range of 0.2 to 1.0 g / min / mouth, and still more preferably in the range of 0.6 to 0.8 g / min. / Mouth range is preferred. Furthermore, the skilled artisan, in order to high nonwoven web uniformity in older melt spinning system, the fiber velocity V _x must generally about 500 meters / min than in the new medium-speed system, It will be appreciated that the fiber speed should generally be greater than about 2000 m / min, and for newer high speed spinning systems, the fiber speed should generally be greater than about 3000 m / min.

One skilled in the art will further appreciate that lower draw ratios V _x / V _o generally result in higher elongation to break in the fiber. In the present invention, if the drop ratio is less than 400, it is possible to produce a fiber having an elongation rate to break generally suitable for the soft stretchable nonwoven fabric in the present invention, more preferably a drop ratio of less than about 150, It has been found that a draw ratio of less than about 50 is preferred. Within the scope of the present invention, a spinneret diameter of less than 200 microns is generally sufficient to obtain low withdrawal and high fiber speed, more preferably less than 150 microns, more preferably Is preferably less than 100 microns. Further, as used herein, the term “extensible” means at least about 400% without significant problems when biasing force is applied, and more preferably at least 600 without significant problems. %, More preferably a fiber that stretches at least 800% without causing significant problems.

  The following examples further illustrate the products and methods of the present invention.

(Example 1)
Example 1 shows melt spinning of a polypropylene resin according to the present invention. Specifically, a vertical single screw extruder is used to spin a polypropylene resin (Valtech HH44, Basell Polyolefins Company, Wilmington, Del.) Into the fiber with a melt flow index 400. This vertical single-screw extruder is mounted on a platform that can be moved up and down, and has a single-mouth capillary and a capillary having a diameter of 86 microns. The molten filament is discharged from the capillary into the ambient air at about 25 ° C. and stretched with a height adjustable air resistance device. This air resistance device uses compressed air supplied at high pressure to create an air flow that serves to stretch the filament around the filament. In the extruder, the production rate is relatively constant about 0.2 g / min / mouth, the distance between the mold outlet and the spraying device is always about 41 inches (104.2 cm), and the distance between the spraying device and the stacking device Always keep about 25 inches (63.5 cm), and for extruder and mold set temperatures, area 1 = 380 ° F. (193 ° C.), area 2 = 400 ° F. (204.4 ° C.), area 3 = 420 ° F. (215.5 ° C.), mold adapter = 425 ° F. (218.3 ° C.), mold = 420 ° F. (215.5 ° C.) To a diameter of less than about 25 microns. Under these conditions, fiber samples having a preferred size diameter in the range of 10-30 microns are made. Example 1 shows that the resin forming the standard fibers is melt-spun according to the present invention.

(Example 2)
Example 2 shows that the fibers produced according to the present invention have high extensibility. Specifically, the fiber sample of Example 1 is analyzed according to ASTM standard D3822. Analysis is performed using a tension tester MTS Synergie 400 (MTS Systems Corporation, Eden Prairie, Minn., USA) equipped with a 10N load cell and air grip. The analysis is carried out at a crosshead speed of 2 inches (5.08 cm) / min for one fiber sample with a gauge length of 1 inch (2.54 cm). The sample is pulled until it breaks, the elongation rate until break is recorded, and the average value of 10 specimens made with the same spraying device pressure is calculated. FIG. 1 shows the results of the elongation rate until breakage. In the figure, the spinning speed is calculated from the equation (1) using the diameter of the fiber measured with a microscope. Example 2 shows that when manufactured according to the present invention, small diameter fibers (10-20 microns) can have a high elongation to break (greater than 600%).

(Comparative Example 3)
Comparative Example 3 compares the extensibility of the fiber of Example 2 with the fiber produced using a conventional spinneret. Specifically, the polypropylene resin of Example 1 was melt-spun into a fiber using a capillary having a diameter of about 570 microns according to the procedure and conditions shown in Example 1, and until the break by the method shown in Example 2 Measure the elongation rate of. FIG. 1 shows the results of the elongation rate until breakage. In the figure, the spinning speed is calculated from the equation (1) using the diameter of the fiber measured with a microscope. It can be seen from Comparative Example 3 that when spinning according to the present invention, the extensibility can be improved without changing the fiber diameter or spinning speed.

  The disclosures of all patents, patent applications (and any patents issued under them, and any foreign patent applications issued in connection therewith), as well as the publications mentioned throughout this specification are hereby incorporated by reference. It is incorporated in the description. It is expressly not admitted, however, that the present invention is taught or disclosed in any of the references given herein for reference.

  While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. All such variations and modifications within the scope of the present invention are intended to be covered by the appended claims.

Graph showing elongation to break for polypropylene with a 400 melt flow index at 0.2 g / min / mouth using capillaries having a diameter of 86 microns and a diameter of 570 microns.

Claims (9)

  5-25 produced by melt spinning the polymer composition such that the discharge rate is 0.01-2.0 g / min / mouth, the draw ratio is less than 400, and the spinneret diameter is less than 200 microns. A fiber with a diameter in the micron range.   5-25 produced by melt spinning the polymer composition such that the fiber elongation to break is greater than 400%, the draw ratio is less than 400, and the spinneret diameter is less than 200 microns. A fiber with a diameter in the micron range.   3. A fiber according to claim 2, wherein the fiber elongation to break is greater than 600%, preferably greater than 800%.   4. The fiber according to any one of claims 1 to 3, wherein the fiber has a diameter in the range of 10 to 20 microns.   The fiber according to any one of claims 1 to 4, wherein the draw ratio is less than 150, preferably less than 50.   6. A fiber according to any one of the preceding claims, wherein the spinneret diameter is less than 150 microns, preferably less than 100 microns.   The fiber according to any one of claims 1 to 6, wherein the polymer composition comprises one or more polymers selected from polyolefins and polyesters.   A nonwoven fabric web comprising the fiber according to any one of claims 1 to 7. A disposable article comprising the nonwoven web of claim 8.

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