EP4791811A1

EP4791811A1 - Polyethylene composition for filaments or fibers

Info

Publication number: EP4791811A1
Application number: EP24783728.9A
Authority: EP
Inventors: Gianni Perdomi; Fabio Di Pietro; Monica Galvan
Original assignee: Basell Polyolefine GmbH
Current assignee: Basell Polyolefine GmbH
Priority date: 2023-10-09
Filing date: 2024-10-04
Publication date: 2026-08-19
Also published as: WO2025078272A1; CN121866297A

Abstract

A polyethylene composition for preparing filaments and fibers, comprising: A) from 75 to 98% by weight of an ethylene polymer component having a density DA from 952 to 965 kg/m3, determined according to ISO 1183-1:2012 at 23°C, a MIF value of from 10 to 35 g/10 min. and a polydispersity index PDIA from 4 to 12; B) from 2 to 25% by weight of an ethylene polymer component having a density DB from 949 to 965 kg/m3, a MIE value from 0.1 to 3 g/10min. and a polydispersity index PDIB from 6 to 25; wherein the value of PDIB is higher than the value of PDIA, both PDIA and PDIB are the ratio Mw/Mn of weight average molecular weight Mw to number average molecular weight Mn and the amounts of A) and B) are referred to the total weight of A) + B).

Description

POLYETHYLENE COMPOSITION FOR FILAMENTS OR FIBERS

FIELD OF THE INVENTION

[0001] The present disclosure concerns a polyethylene composition for filaments or fibers.

BACKGROUND OF THE INVENTION

[0002] The term “filaments” is generally used to make a distinction with respect to the fibers for textile and carpeting applications.

[0003] Thus the present filaments are preferably characterized by a titre of at least 50 denier (hereinafter called “den”).

[0004] Typical applications for said filaments are ropes and yams for nets, geotextiles and protective netting in agriculture and building industry.

[0005] According to W02007082817 filaments, monotapes or stretched tapes having good mechanical properties are obtained from a composition comprising ethylene polymers and butene- 1 polymers.

[0006] In many applications, like those reported above, it is in fact desirable to obtain a high balance of tenacity and elongation.

[0007] It has now been found that such goal can be achieved when the filaments are prepared with compositions comprising a blend of specific ethylene polymers, without the need to add other polymer components, like butene- 1 polymers.

SUMMARY OF THE INVENTION

[0008] Thus the present disclosure provides a polyethylene composition, hereinafter called “polyethylene composition (I)”, comprising:

A) from 75 to 98% by weight, preferably from 85 to 97% by weight, of an ethylene polymer component having a density D^A from 952 to 965 kg/m³, preferably from 955 to 962 kg/m³, determined according to ISO 1183-1 :2012 at 23°C, a MIF value of from 10 to 35 g/10 min., preferably from 10 to 25 g/10 min., wherein MIF is the Melt Flow Index MI measured according to ISO 1133-1 :2011 at 190°C with a load of 21.6 kg, and a poly dispersity index PDI^A from 4 to 12, preferably from 5 to 10;

B) from 2 to 25% by weight, preferably from 3 to 15% by weight, of an ethylene polymer component having a density D^B from 949 to 965 kg/m³, preferably from 952 to 960 kg/m³, a MIE value from 0.1 to 3 g/10min., preferably from 0.5 to 2 g/10min., wherein MIE is the Melt Flow Index MI measured according to ISO 1133-1 :2011 at 190°C with a load of 2.16 kg, and a poly dispersity index PDI^B from 6 to 25, preferably from 9 to 20; wherein the value of PDI^B is higher than the value of PDI^A, both PDI^A and PDI^B are the ratio Mw/Mn of weight average molecular weight Mw to number average molecular weight Mn, measured by Gel Permeation Chromatography (GPC) and the amounts of A) and B) are referred to the total weight of A) + B).

[0009] The present disclosure provides also a filament or fiber comprising the above described polyethylene composition (I).

[0010] As other polyolefin components and/or components different from polyolefins can be present in the filament or fiber, it is to be understood that the present polyethylene composition (I) can constitute the overall polymer composition present in the filament or fiber, or be part of such polymer composition, and the total weight of the filament or fiber can be the sum of the said polyethylene composition (I) and of other components.

[0011] Due to their balance of tenacity and elongation, the present filaments are particularly useful for preparing nets and ropes, preferably anti hail nets and high tenacity ropes.

[0012] The said properties are clearly desirable also for low titre fibers, for instance for textile applications, and chopped short fibers and are achieved to the maximum extent when the filaments and fibers are oriented by stretching.

DETAILED DESCRIPTION OF THE INVENTION

[0013] Both the ethylene polymer components A) and B) may comprise one or more ethylene polymer(s) selected from ethylene homopolymers, ethylene copolymers and their mixtures.

[0014] The term "copolymer" as used herein includes polymers containing one kind or more than one kind of comonomers.

[0015] In the ethylene copolymers the comonomers are preferably selected from olefins having formula CH2=CHR wherein R is an alkyl radical, linear or branched, or an aryl radical, having 1 to 8 carbon atoms.

[0016] Specific examples are propylene, butene-1, pentene-1, 4-methylpentene-l, hexene-1, octene- 1 and decene- 1.

[0017] Particularly preferred are butene-1 and hexene-1.

[0018] The molecular weight distribution of the ethylene polymer components A) and B) can be monomodal, bimodal or multimodal. In the present disclosure, a monomodal molecular weight distribution means that the molecular weight distribution, as determined with Gel Permeation Chromatography (GPC), has a single maximum. The molecular weight distribution curve of a GPC-multimodal polymer can be looked at as the superposition of the molecular weight distribution curves of two or more polymer subfractions and will accordingly show two or more distinct maxima or will at least be distinctly broadened compared with the curves for the individual fractions.

[0019] Preferred polyethylene compositions (I) are those wherein PDI^B - PDI^A, which is the difference between the PDI values of B) and A) respectively, is equal to or greater than 2, more preferably equal to or greater than 3, most preferably equal to or greater than 4, in particular:

- from 2 to 10, or

- from 3 to 10, or

- from 4 to 10, or

- from 2 to 8, or

- from 3 to 8, or

- from 4 to 8.

[0020] Independently or in combination with the above PDI difference, preferred polyethylene compositions (I) are those wherein D^A - D^B, which is the difference between the density values of A) and B) respectively, is from 1 to 5, more preferably from 1.5 to 4 kg/m³.

[0021] Advantageously but not necessarily, the ethylene polymer component A) has a weight average molecular weight Mw equal to or lower than 300000 g/mol (in particular, equal to or lower than 250000 g/mol).

[0022] In some non-limiting cases, the ethylene polymer component A) has a Mw equal to or higher than 90000 g/mol (in particular, equal to or higher than 120000 g/mol).

[0023] Advantageously but not necessarily, the ethylene polymer component B) has a weight average molecular weight Mw equal to or lower than 170000 g/mol (in particular, equal to or lower than 160000 g/mol).

[0024] In some non-limiting cases, the ethylene polymer component B) has a Mw equal to or higher than 90000 g/mol (in particular, equal to or higher than 100000 g/mol).

[0025] According to some non-limiting embodiments, the ethylene polymer component B) has z-average molecular weight Mz lower than 800000 g/mol (in particular, equal to or lower than 750000 g/mol); in particular, equal to or higher than 200000 g/mol (more in particular, equal to or higher than 250000 g/mol).

[0026] Advantageously but not necessarily, the ethylene polymer component B) has a Melt Index MIF from 5 to 28 g/10min., more preferably from 10 to 25 g/lOmin.

[0027] Particularly preferred MIF/MIP values for both the ethylene polymer component A) and the ethylene polymer component B) are from 4 to 20, more preferably from 5 to 15. [0028] Said homopolymers and copolymers can be obtained by way of polymerization processes in the presence of coordination catalysts. Said processes and the homopolymers and copolymers obtained from them are widely described in the art.

[0029] In particular it is possible to carry out the polymerization process in the presence of a Ziegler-Natta catalyst or single site catalyst.

[0030] As is well known, a Ziegler-Natta catalyst comprises the product of the reaction of an organometallic compound of group 1, 2 or 13 of the Periodic Table of elements with a transition metal compound of groups 4 to 10 of the Periodic Table of Elements (new notation). In particular, the transition metal compound can be selected among compounds of Ti, V, Zr, Cr and Hf and is preferably supported on MgCh.

[0031] Particularly preferred catalysts comprise the product of the reaction of said organometallic compound of group 1, 2 or 13 of the Periodic Table of elements, with a solid catalyst component comprising a Ti compound supported on MgCh.

[0032] Preferred organometallic compounds are the organo-Al compounds.

[0033] The single site catalysts are known in the art and are generally selected from metallocene and non-metallocene single site catalysts.

[0034] Examples of metallocene single site catalysts are zirconocenes and hafnocenes, for instance cyclopentadienyl or indenyl complexes of zirconium or hafnium, like bis (cyclopentadienyl) zirconium dichloride; bis (indenyl) zirconium dichloride or bis (indenyl) hafnium di chloride.

[0035] Examples of non-metallocene single site catalysts are iron complex compounds preferably having a tridentate ligand.

[0036] Particularly suited tridentate ligands are 2,6-Bis[l-(phenylimino)ethyl] pyridine and preferably the corresponding compounds wherein both the two phenyl groups are substituted in the ortho-position with a halogen or tert, alkyl substituent.

[0037] Specific examples are 2,6-Bis[l-(2-tert.butylphenylimino)ethyl]pyridine iron(II) dichloride; 2,6-Bis[l-(2-tert.butyl-6-chlorophenylimino)ethyl]pyridine iron(II) dichloride or 2,6- Bis[l-(2,4-dichlorophenylimino)ethyl]pyridine iron(II) dichloride.

[0038] Said metallocene and non-metallocene single site catalysts can also be used in combination.

[0039] Preferably, the single site catalysts are reacted with activating compounds (cocatalysts), preferred examples of which are aluminoxanes, such as mono-methylaluminoxane (MAO), for instance. [0040] The polymerization, which can be continuous or batch, is carried out, in the presence of said catalysts, following known techniques and operating in liquid phase, in the presence or not of inert diluent, or in gas phase, or by mixed liquid-gas techniques.

[0041] Reaction time, pressure and temperature relative to the polymerization steps are not critical, however it is best if the temperature is from 50 to 100°C. The pressure can be atmospheric or higher.

[0042] The regulation of the molecular weight is carried out by using known regulators, hydrogen in particular.

[0043] All the said ethylene homopolymers and copolymers are available on the market. Specific commercial polymers suited for producing the present polymer blend are described in the examples.

[0044] The polyethylene composition (I) is obtainable by melting and mixing the components, and the mixing is effected in a mixing apparatus at temperatures generally of from 180 to 310°C, preferably from 190 to 280°C, more preferably from 200 to 250°C.

[0045] Any known apparatus and technology can be used for this purpose.

[0046] Useful melt-mixing apparatus in this context are in particular extruders or kneaders, and particular preference is given to twin-screw extruders. It is also possible to premix the components at room temperature in a mixing apparatus.

[0047] During the preparation of the polyethylene composition (I), besides the main components A) and B) and other optional components, it is possible to introduce additives commonly employed in the art, such as stabilizing agents (against heat, light, U. V.), plasticizers, antiacids, antistatic and water repellant agents, pigments, polymer processing aids.

[0048] Preferably, the present filament or fiber comprises at least 70% by weight of the polyethylene composition (I), more preferably at least 80% by weight, in particular 90% or 95% by weight of polyethylene composition (I), with respect to the total weight of the filament or fiber, the upper limit being 100% by weight in all cases.

[0049] The present filaments are typically characterized by a rounded (circular, oval, lenticular or even more complex, like multilobal) cross-section, or by an angular, like rectangular, crosssection.

[0050] The filaments having rounded cross-section are also called “monofilaments” while those having angular and in particular rectangular cross-section are also called “tapes”. Thus the present definition of “filament” comprises the said monofilaments and tapes.

[0051] Preferably the tapes have a thickness from 0.03 to 1 mm and width from 2 to 20 mm. [0052] As previously said, the filaments are preferably characterized by a titre of at least 50 den.

[0053] Particularly preferred titre values for the filaments are of at least 70 den, especially of at least 100 or 200, in particular of at least 500 den, the upper limit being preferably, in all cases, of 7000 den for monofilaments and of 25000 den for tapes.

[0054] As previously mentioned, the filament is preferably stretched. Particularly preferred are stretching ratios from 1.5 to 10 (1.5:1 to 10: 1), in particular from 3 to 10 (3: 1 to 10: 1). These preferred stretching ratios apply also to the fibers.

[0055] Particularly preferred tenacity values for the filaments are of 4 g/den or higher, more preferably they are from 4 to 7.

[0056] Particularly preferred values of elongation at break for the filaments are of 20% or higher, more preferably they are from 20% to 50%.

[0057] Moreover, as previously mentioned, the filaments can comprise components made of materials different from polyolefins, like embedded reinforcing fibers, made for example of polyamide.

[0058] All the said filaments can be used in the form of bundles for preparation of various finished articles.

[0059] Another way of obtaining bundles of filaments is by fibrillation of tapes having relatively large width.

[0060] The present polyolefin filaments or fibers can be prepared by means of processes and apparatuses well known in the relevant art.

[0061] In general terms, the process for preparing polyolefin filaments comprises the following steps:

(a) melting the polyethylene composition (I) and the other polymer components, when present;

(b) spinning the filaments or extruding a precursor film or tape;

(c) optionally stretching the filaments or the precursor film or tape and/or cutting the precursor film or tape and optionally stretching the so obtained filaments, when no stretching is previously carried out;

(d) optionally finishing the filaments obtained from step (b) or (c).

[0062] The melting step (a) and the spinning or extrusion step (b) are generally carried out continuously in sequence by using mono- or twin-screw extruders, equipped with a suited spinning or extrusion head. Thus also the previously described melt-mixing step can be carried out in the same spinning or extrusion apparatus. [0063] The spinning heads comprise a plurality of holes with the same shape as the transversal section of the filament (monofilament or tape).

[0064] The film extrusion heads are generally flat or annular dies commonly used for the film preparation.

[0065] When a precursor film or tape is obtained in step (b), it is then processed in step (c) by cutting it into tapes having the desired size. When the stretching treatment is carried out on the precursor film or tape, it is consequently no longer required on the final filament.

[0066] Examples of finishing treatments can be fibrillation and crimping.

[0067] Fibrillation is generally carried out on tapes.

[0068] Typically the melting step (a) and the spinning or extrusion step (b) are carried out at the same temperatures as previously defined for the melt-mixing step, namely of from 180 to 310°C, preferably from 190 to 280°C, more preferably from 200 to 250°C.

[0069] Typical spinning conditions are: temperature in the extruder head from 200 to 300°C;

- take-up speed for primary web (unstretched) from 1 to 50 m/min.

[0070] Typical film extrusion conditions are: temperature in the extruder head from 200 to 300°C; output value from 20 to 1000 kg/hour (on industrial plants).

[0071] The filament or the precursor film obtained in step (b) are generally cooled by using for instance one or more chill rolls or by immersion in water at a temperature from 5 to 40°C.

[0072] To carry out the stretching treatment, the filament (monofilament or tape) or the precursor tape are previously heated at a temperature from 40 tol20-140°C. Heating can be achieved by using for example a hot air oven, a boiling water bath, heated rolls or by irradiation or other known means.

[0073] Stretching can be achieved by delivering the precursor tape or filament through a series of rollers having different rotation speeds. Preferred ranges of stretching ratios so achieved are those previously specified.

[0074] The stretching ratio is the ratio between the high speed of the rollers of the stretching unit and the speed of the rollers of the take-off unit (primary speed). As previously mentioned, in the take-off unit the tape or filament moving at low speed is heated before being stretched by applying faster speed.

[0075] Fibrillation can be achieved by feeding the tape between rolls having means for cutting longitudinally and/or diagonally. [0076] Fibers with lower denier than filaments, namely with a titre under 50 den, typically from 1 to 15 den, are prepared by extruding the polymer melt through the already described spinning heads, wherein the holes have a smaller diameter with respect to the diameter used for filaments. The fibers emerging from the spinning head are subsequently subjected to quenching and oriented by stretching in a manner similar to that described above with reference to the orientation of the filaments.

[0077] The apparatuses and spinning conditions typically used to prepare fibers are well known in the art.

EXAMPLES

[0078] The practice and advantages of the various embodiments, compositions and methods as provided herein are disclosed below in the following examples. These Examples are illustrative only, and are not intended to limit the scope of the appended claims in any manner whatsoever.

[0079] The following analytical methods are used to characterize the polymer compositions and filaments.

[0080] Density

[0081] Determined according to ISO 1183-1 :2012 at 23°C.

[0082] Melt Flow Index MI

[0083] Determined according to ISO 1133-1 :2011 with the specified temperature and load.

[0084] Molecular Weight Distribution Determination

[0085] The determination of the means Mw, Mn and Mz and of Mw/Mn derived therefrom was carried out by high-temperature gel permeation chromatography using a method described in ISO 16014-1, -2, -4, issue of 2003. The specifics according to the mentioned ISO standards are as follows: Solvent 1, 2, 4-tri chlorobenzene (TCB), temperature of apparatus and solutions 145°C and as concentration detector a PolymerChar (Valencia, Paterna 46980, Spain) IR-4 infrared detector, capable for use with TCB. A WATERS Alliance 2000 equipped with the following pre-column SHODEX UT-G and separation columns SHODEX UT 806 M (3x) and SHODEX UT 807 (Showa Denko Europe GmbH, Konrad-Zuse-Platz 4, 81829 Muenchen, Germany) connected in series was used.

[0086] The solvent was vacuum distilled under Nitrogen and was stabilized with 0.025% by weight of 2,6-di-tert-butyl-4-methylphenol. The flowrate used was 1 ml/min, the injection was 500pl and polymer concentration was in the range of 0.01% < cone. < 0.05% w/w. The molecular weight calibration was established by using monodisperse polystyrene (PS) standards from Polymer Laboratories (now Agilent Technologies, Herrenberger Str. 130, 71034 Boeblingen, Germany) in the range from 580g/mol up to 11600000g/mol and additionally with Hexadecane. [0087] The calibration curve was then adapted to Polyethylene (PE) by means of the Universal Calibration method (Benoit H., Rempp P. and Grubisic Z., & in J. Polymer Sci., Phys. Ed., 5, 753(1967)). The Mark-Houwing parameters used herefore were for PS: kps= 0.000121 dl/g, aps=0.706 and for PE kpr= 0.000406 dl/g, CU>E=0.725, valid in TCB at 135°C. Data recording, calibration and calculation was carried out using NTGPC_Control_V6.02.03 and NTGPC V6.4.24 (hs GmbH, HauptstraBe 36, D-55437 Ober-Hilbersheim, Germany) respectively.

[0088] Comonomer content

[0089] The comonomer content was determined by means of IR in accordance with ASTM D 6248 98, using an FT-IR spectrometer Tensor 27 from Bruker, calibrated with a chemometric model for determining ethyl- side-chains in PE for butene- 1 as comonomer and butyl- side-chains in PE for hexene- 1 as comonomer.

[0090] Titre, Tenacity and Elongation at break of filaments

[0091] The titre in deniers is commonly used to measure the size of textile fibres and filaments and is defined as the weight (in grams) of 9000 m of filament or tape. At laboratory scale the actual titre (in deniers) is determined by multiplying the weight of 100 m of filament or tape by 90 times. [0092] Tenacity and elongation at break are measured by using a dynamometer, for instance a LLOYD RX-Plus, on a single filament, with clamps distance of 250 mm and applied elongation speed of 250 mm/min.

[0093] The load cell provides the load at break (in grams or Kg) while elongation at break (%) is calculated as follows:

(clamps distance at break - initial clamps distance / initial clamps distance) * 100. [0094] The tenacity (at break) is obtained by dividing the load at break (in grams) by the titre in deniers.

[0095] Examples 1 and 2 and Comparative Example 1

[0096] The following materials are used to prepare the polyethylene composition (I).

[0097] Ethylene polymer component A)

[0098] Ethylene copolymer prepared with a Ziegler-Natta catalyst, having the properties reported in Table I below.

[0099] It is available on the market with trademark Hostalen GF 7750 M3, sold by LyondellBasell.

[0100] Ethylene polymer component B) [0101] Ethylene copolymer having the properties reported in Table I below.

[0102] It is available on the market with trademark Luflexen hyPE 56P FA, sold by LyondellBasell.

Table

[0103] Preparation of the polyethylene composition (I)

[0104] Components A) and B) were mixed with a usual stabilizing additive composition and blended together by extrusion in a twin screw extruder Berstorff ZE 25 (length/diameter ratio of screws: 34) under nitrogen atmosphere in the following conditions:

[0105] Rotation speed: 250 rpm;

[0106] Extruder output: 15 kg/hour;

[0107] Melt temperature: 245 °C. [0108] The stabilizing additive composition was made of the following components:

[0109] - 0.1% by weight of Irganox® 1010;

[0110] - 0.1% by weight of Irgafos® 168;

[oni] - 0.2% by weight of calcium stearate;

[0112] all percent amounts being referred to the total weight of the polymer and stabilizing additive composition.

[0113] The said Irganox® 1010 is 2,2-bis[3-[,5-bis(l,l-dimethylethyl)-4-hydroxyphenyl)-l- oxopropoxy]methyl]-l,3-propanediyl-3,5-bis(l,l-dimethylethyl)-4-hydroxybenzene-propanoate, while Irgafos® 168 is tris(2,4-di-tert.-butylphenyl)phosphite.

[0114] The so obtained polyethylene composition (I) was spun into filaments with circular cross-section.

[0115] The apparatus used was an extruder Leonard, 25 mm diameter, 27 L/D long + Gear pump. The die had 10 holes, circular shaped, with a diameter of 1.4 mm.

[0116] The main process conditions were:

Temperature profile: - Cylinder 190-220-225-230 °C;

- Pump 245 °C;

- Adapter 255 °C;

- Head-die 260 °C;

Melt temperature: 257+/- 3 °C;

Output used: around 3.2 kg/h;

Cooling water bath: 16 +/-1 °C;

Stretching bath set: 97 +/-1 °C (hot air);

Annealing oven set: 112 +/-3 °C (hot air);

Annealing factor: average -3.0 % (slower).

[0117] The properties of the so obtained filaments are reported, for all the examples, in Table II. Table II

Claims

CLAIMS What is claimed is:

1. A polyethylene composition (I) comprising:

A) from 75 to 98% by weight, preferably from 85 to 97% by weight, of an ethylene polymer component having a density D^A from 952 to 965 kg/m³, preferably from 955 to 962 kg/m³, determined according to ISO 1183- 1:2012 at 23°C, a MIF value of from 10 to 35 g/10 min., preferably from 10 to 25 g/10 min., wherein MIF is the Melt Flow Index MI measured according to ISO 1133-1 :2011 at 190°C with a load of 21.6 kg, and a poly dispersity index PDI^A from 4 to 12, preferably from 5 to 10;

B) from 2 to 25% by weight, preferably from 3 to 15% by weight, of an ethylene polymer component having a density D^B from 949 to 965 kg/m³, preferably from 952 to 960 kg/m³, a MIE value from 0.1 to 3 g/10min., preferably from 0.5 to 2 g/10min., wherein MIE is the Melt Flow Index MI measured according to ISO 1133-1 :2011 at 190°C with a load of 2.16 kg, and a poly dispersity index PDI^B from 6 to 25, preferably from 9 to 20; wherein the value of PDI^B is higher than the value of PDI^A, both PDI^A and PDI^B are the ratio Mw/Mn of weight average molecular weight Mw to number average molecular weight Mn, measured by Gel Permeation Chromatography (GPC) and the amounts of

A) and B) are referred to the total weight of A) + B).

2. The polyethylene composition of claim 1 or 2, wherein PDI^B - PDI^A, which is the difference between the PDI values of B) and A) respectively, is equal to or greater than 2, more preferably equal to or greater than 3, most preferably equal to or greater than 4.

3. The polyethylene composition of claim 1 or 2, wherein D^A - D^B, which is the difference between the density values of A) and B) respectively, is from 1 to 5, more preferably from 1.5 to 4 kg/m³.

4. The polyethylene composition of claim 1 or 2, wherein the ethylene polymer component

B) has a z-average molecular weight Mz lower than 800000 g/mol, preferably equal to or lower than 750000 g/mol.

5. The polyethylene composition of claim 1 or 2, wherein the ethylene polymer component B) has a Melt Index MIF from 5 to 28 g/10min., preferably from 10 to 25 g/lOmin.

6. The polyethylene composition of claim 1 or 2, wherein the MIF/MIP values for both the ethylene polymer component A) and the ethylene polymer component B) are from 4 to 20, more preferably from 5 to 15.

7. Filament or fiber, comprising the polyethylene composition (I) of claim 1.

8. The filament or fiber of claim 8, stretched with a stretching ratio from 1.5: 1 to 10: 1.

9. Manufactured items containing filaments according to claim 7 or 8.

10. The manufactured items according to claim 9, in form of nets or ropes or chopped short fibers.