EP1330564B1 - Method for the spinning and winding of polyester filaments using a spinning additive, polyester filaments obtained by the spinning method, draw texturing of the polyester filaments and bulked polyester filaments obtained by draw texturing - Google Patents

Abstract

Production of preoriented and melt spun polyester filaments comprising 90 wt.% of polybutylene terephthalate (PBT) of the total polyester filament weight and/or polytrimethylene terephthalate (PTMT) involves setting the spin draft, cooling directly and bundling together at a gap of 500-2500 mm. Production and winding of preoriented and melt spun polyester filaments comprising at least 90 wt.% of polybutylene terephthalate (PBT) of the total polyester filament weight and/or polytrimethylene terephthalate (PTMT) and is preferably wholly of PTMT. The spin draft is set at 70-500. The filaments are cooled directly on leaving the spinneret for a length of 30-200 mm, to a temperature below the setting point, and bundled together at a gap of 500-2500 mm from the under side of the spinneret. The filament tension before and between the godet rollers is 0.05-0.20 cN/dtex. The filament winding speed is 2200-6000 m/min. The polyester contains a polymer additive to increase its stretch, mixed in at a rate of 0.05-2.5 wt.% of the total filament weight. Independent claims are included for: (1) preoriented polyester filaments which, after four weeks of storage, have a stretch to break of 90-165%, a boiling shrinkage of at least 30%, a normal uster of =1.1%, a double refraction of 0.030-0.058, a density of =1.35 g/cm 3> and preferably =1.33 g/cm 3>, a variation coefficient of the shearing load and stretch to break of =4.5%; and (2) a bulked polyester filament, where the POY yarns are passed through a draw texturizing unit at a speed of at least 500 m/min. with a drafting ratio of at least 1:1.35 to give a bulked filament yarn with a shear strength of >=26 cN/tex and a stretch to break of >=30% or >=36%.

Description

The present invention relates to methods for spinning and winding of preoriented polyester filaments using spin additives, which at least 90% by weight based on the total weight of the polyester filament of polybutylene terephthalate (PBT) and / or Polytrimethylene terephthalate (PTMT), preferably from PTMT, as well as the preoriented polyester filaments obtainable by the process. Of Further, the present invention also relates to methods for Stretch texturing of spun and wound polyester filaments as well the bulky polyester filaments obtainable by stretch texturing.

The production of continuous polyester filaments, in particular of Polyethylene terephthalate (PET) filaments, in a two-stage process already known. In the first stage, smooth preoriented filaments are produced spun and wound, the finished in a second stage and stretched heat-set or stretch-texturized to bulky filaments.

An overview of this is provided by the book Synthetic Fibers by F. Fourné (1995), published by Hanser-Verlag Munich. However, only the Production of PET fibers described, with no closed Rather, an overview is presented in which the various features are described.

The fiber production of various spinnable polymers, among others Polypropylene, polyamides, polyesters, etc. are the subject of the application DE-OS 38 19 913. However, in the examples, only the production of PET fibers described how this can be taken from the temperature at which the Polymer is processed.

In the preparation of continuous polytrimethylene terephthalate (PTMT) -or Polybutylene terephthalate (PBT) filaments has the problem that Preoriented filaments both directly after spinning and when winding as even several hours after rewinding when storing in Ambient temperature have a considerable tendency to shrink, resulting in a Thread shortening leads. The bobbin is thereby compressed, so that it in extreme cases, a shrinkage of the bobbin on the Aufspuldorn comes and the winding body can not be removed. Farther forms in the winding body, a so-called saddle with hard edges and run in middle part. As a result, textile characteristics of the filaments, such as the Uster more uneven and there are flow problems when working off the wraps. Such problems occur in the processing of PET fibers do not open.

Furthermore, it is observed that, in contrast to PET filaments, preoriented PBT or PTMT filaments age more when stored. It occurs one Structure hardening, which leads to such a strong drop in the Cooking shrinkage leads that a Nachkristallisation can be detected. Such PBT or PTMT filaments are for further processing only conditionally suitable, they lead to errors in the stretch texturing and to a Significant reduction in tear strength of the textured yarn.

These differences between PET and PBT or PTMT are due to structural and Attribute differences, such as those in Chemical Fibers Int., P. 53, vol. 50 (2000) and theme on the 39th Int. Man made Fiber Congress, from 13 to 15 Sept. in Dornbirn. So will assume that different chain formations for the Property differences are responsible.

First approaches to solving these problems are described in the patent application WO 99/27168 and European Patent EP 0,731,196 B1. WHERE 99/27168 discloses a polyester fiber comprising at least 90% by weight Polytrimethylene terephthalate and a boiling shrinkage between 5% and 16% and an elongation at break of 20% to 60%. The production of in WO 99/27168 described polyester fiber is made by spinning and Stretching. This spin spinning speeds of at most 2100 m / min specified. The procedure is due to the low Spinning speed uneconomical. In addition, the obtained Polyester fibers, as the indicated figures show, strongly crystalline and thus only partially suitable for draw texturing.

European patent EP 0,731,196 B1 claims a method for spinning, Stretching and winding a synthetic thread, with the thread after the stretching and before winding to reduce the Shrinkage is subjected to a heat treatment. usable Synthetic fibers also include polytrimethylene terephthalate fibers. According to EP 0,731,196 B1, the heat treatment is carried out in that the synthetic Thread in close proximity but substantially without contact along an elongated heating surface is performed. The application of a Heat treatment makes the process more expensive and also supplies synthetic threads with high crystallinity, which are only partially suitable for draw texturing.

In the article by Dr. H.S. Brown and H.H. Chuah; "Texturing of textile filament yarns based on polytrimethylene terephthalate "Chemical Fibers International, Volume 47, Feb. 1997, pp. 72-74, the draw texturing of pre-oriented polytrimethylene terephthalate filaments Texturing speeds of 450 m / min and 850 m / min described. According to this disclosure is the lower texturing speed of 450 m / min for Polytrimethylene terephthalate filaments more suitable, since in this case fibers obtained with better material properties. The tensile strength of the Polytrimethylene terephthalate fibers is 26.5 cN / tex (Texturing speed of 450 m / min) or 29.15 cN / tex (Texturing speed of 850 m / min) and the elongation at break of 38.0% (Texturing speed of 450 m / min) or 33.5% (Texturing speed of 850 m / min) specified.

The document WO 01/04393 describes PTMT filaments which have a Boiling shrinkage in the range of 3 to 40%. This value will however determined immediately after the production of the filaments. After a storage period of 4 weeks under normal conditions, this value decreases below 20% as this the attached Figure 1 shows.

Figure 1 describes the change in boiling shrinkage for three PTMT-POY coils depending on the storage time under normal climatic conditions. in this connection was the change in the POY cooking shrinkage for three coils with different initial value over the storage time at normal Climatic conditions examined. The spools No. 16 and 17 with high Initial value> 40% show after 4 weeks a boiling shrinkage above 30%, preferably above 40%. If the initial value of the boiling shrinkage However, less than 40%, so the coil 18 shows that this after 4 weeks Storage time, however, falls below the critical value of 30%.

The shrinkage is a measure of the processability and the Degree of crystallization of the fibers. The fibers described in WO 01/04393 have Plastics with a higher degree of crystallization, which is essential worse and only at lower draw ratio and / or lower Process the texturing speed.

In view of the prior art, it was now the task of the present Invention, a method for spinning and winding of preoriented Polyester filaments containing at least 90 wt .-% based on the Total weight of the filaments of PBT and / or PTMT exist which is the manufacture and winding of pre-oriented Polyester filaments in a simple manner allows. In particular, should the preoriented polyester filaments have elongation at break in the range of 90% - 165%, a high uniformity in terms of filament characteristics and have a low degree of crystallinity.

Another object of the present invention was a method for spinning and winding of preoriented polyester filaments, which is industrially and inexpensively feasible. The invention Procedure should be as high take-off speeds, preferably greater 2200 m / min and high thread weights on the bobbin of more than 4 kg, allow.

It was also an object of the present invention to improve the shelf life of the invention Preoriented polyester filaments obtainable by the process according to the invention to improve. These should also be for a longer period, for example, 4 weeks, be storable. A Zusammenpreßen the bobbin during storage, in particular a shrinkage of the bobbin on the Aufspuldorn and the formation of a saddle with hard edges and run in middle part should be prevented if possible, so that There are no problems when processing the winding.

According to the invention, the pre-oriented polyester filaments should be simple and manner in a stretch texturing process, especially at high Texturing speeds, preferably greater than 450 m / min, further processed can be. The filaments obtainable by stretch texturing should have excellent material properties, for. B. a high tensile strength of more than 26 cN / tex and a high elongation at break of more than 30% for HE filaments or more than 36% for SET filaments.

These are solved as well as other not explicitly mentioned tasks, however from the contexts discussed hereinbefore readily derivable or be developed by a method for spinning and winding with all Features of claim 1. Advantageous modifications of The method according to the invention are referred to in claim 1 Subclaims under protection. The one obtainable by the spinning process Pre-oriented polyester filament is the independent product claim described. The draw texturing of the preoriented polyester filament becomes claimed in the method claim 7, while the product claims 8 and 9 refer to the bulky filaments obtainable by stretch texturing.

a) der Spinnverzug im Bereich 70 bis 500 eingestellt wird,

b) die Filamente direkt nach Austritt aus der Spinndüse eine Abkühlungsverzögerungszone von 30 mm bis 200 mm Länge durchlaufen,

c) die Filamente unter die Erstarrungstemperatur abgekühlt werden,

d) die Filamente in einem Abstand zwischen 500 mm und 2500 mm von der Düsenunterseite gebündelt werden,

e) die Fadenspannung vor und zwischen den Abzugsgaletten zwischen 0,05 cN/dtex bis 0,20 cN/dtex eingestellt wird,

f) der Faden mit einer Fadenspannung zwischen 0,025 cN/dtex bis 0,15 cN/dtex aufgespult wird,

g) die Aufspulgeschwindigkeit zwischen 2200 m/min und 6000 m/min eingestellt wird,

h) und ein Polyester eingesetzt wird, welchem 0,05 Gew.-% bis 2,5 Gew.-% bezogen auf das Gesamtgewicht des Filaments an Additiv-Polymer als Dehnungserhöhungsmittel beigemischt sind,

gelingt es auf nicht ohne weiteres vorhersehbare Weise vororientierte Polyester-Filamente zur Verfügung zu stellen, die auch nach einer Lagerung bei Normalbedingungen für 4 Wochen ihre hervorragenden Materialeigenschaften bewahren. Eine signifikante Verschlechterung der Gleichmäßigkeitswerte des Fadens infolge einer Alterung bzw. ein Wickelschrumpf der gesponnenen Faser auf der Spule ist nicht zu beobachten.By having at least 90% by weight, based on the total weight of the polyester filament, of polybutylene terephthalate (PBT) and / or polytrimethylene terephthalate (PTMT), preferably of PTMT, of a process for making and winding up preoriented polyester filaments .

a) the spinning delay is set in the range 70 to 500,

b) the filaments go through a cooling delay zone of 30 mm to 200 mm length directly after leaving the spinneret,

c) the filaments are cooled below the solidification temperature,

d) the filaments are bundled at a distance of between 500 mm and 2500 mm from the nozzle base,

e) the thread tension is adjusted between 0.05 cN / dtex and 0.20 cN / dtex before and between the withdrawal godets,

f) the thread is wound with a thread tension between 0.025 cN / dtex to 0.15 cN / dtex,

g) the winding speed is set between 2200 m / min and 6000 m / min,

h) and a polyester is used, to which 0.05% by weight to 2.5% by weight, based on the total weight of the filament, of additive polymer is added as a strain-increasing agent,

It is possible to provide pre-oriented polyester filaments in a manner which can not be foreseen without further ado, which retain their excellent material properties even after storage under normal conditions for 4 weeks. A significant deterioration of the uniformity values of the thread due to aging or winding shrinkage of the spun fiber on the bobbin is not observed.

• Das erfindungsgemäße Verfahren ist auf einfache Art und Weise, großtechnisch und kostengünstig durchführbar. Insbesondere erlaubt das Verfahren das Spinnen und Aufspulen bei hohen Abzugsgeschwindigkeiten von mindestens 2200 m/min und die Herstellung hoher Fadengewichte auf dem Spulkörper von mehr als 4 kg.
• Durch den Einsatz von Spinnadditiven können Abzugsgeschwindigkeiten von bis zu 6000 m/min erzielt werden. Hierdurch können die Anlagen besonders wirtschaftlich betrieben werden.
• Die durch das Verfahren erhältlichen vororientierten Polyester-Filamente können somit auf einfache Art und Weise, großtechnisch und kostengünstig in einem Streck- bzw. einem Strecktexturierprozeß weiterverarbeitet werden. Dabei kann die Texturierung bei Geschwindigkeiten größer 450 m/min erfolgen.
• Aufgrund der hohen Gleichmäßigkeit der durch das Verfahren erhältlichen vororientierten Polyester-Filamente ist es auf einfache Art und Weise möglich, einen guten Spulenaufbau einzustellen, der eine gleichmäßige und nahezu fehlerfreie Anfärbung und Weiterverarbeitung des vororientierten Polyester-Filaments erlaubt.
• Die durch die Strecktexturierung erhältlichen Filamente weisen eine hohe Reißfestigkeit von mehr als 26 cN/tex und eine hohe Reißdehnung von mehr als 30 % für HE-Filamente bzw. mehr als 36 % für SET-Filamente auf.

At the same time, the inventive method has a number of other advantages. These include:

• The method according to the invention can be carried out in a simple manner, on an industrial scale and inexpensively. In particular, the method allows spinning and winding at high take-off speeds of at least 2200 m / min and the production of high thread weights on the bobbin of more than 4 kg.
• Through the use of spin additives, take-up speeds of up to 6000 m / min can be achieved. As a result, the plants can be operated particularly economically.
• The preoriented polyester filaments obtainable by the process can thus be further processed in a simple manner, on an industrial scale and inexpensively in a stretch or draw texturing process. The texturing can take place at speeds greater than 450 m / min.
• Due to the high uniformity of the preoriented polyester filaments obtainable by the process, it is possible in a simple manner to set up a good package construction which permits a uniform and virtually error-free dyeing and further processing of the preoriented polyester filament.
• The filaments obtainable by draw texturing have a high tensile strength of more than 26 cN / tex and a high elongation at break of more than 30% for HE filaments and more than 36% for SET filaments.

The present invention relates to a process for the production and for winding preoriented polyester filaments which are at least 90 Wt .-% based on the total weight of the filament Polybutylene terephthalate (PBT) and / or polytrimethylene terephthalate (PTMT) consist. Polybutylene terephthalate (PBT) and / or polytrimethylene terephthalate (PTMT) are known in the art. Polybutylene terephthalate (PBT) can by Polycondensation of terephthalic acid with equimolar amounts of 1,4-butanediol, Polytrimethylene terephthalate by polycondensation of Terephthalic acid with equimolar amounts of 1,3-propanediol can be obtained. Also mixtures of the two polyesters are conceivable. According to the invention preferred becomes PTMT.

The polyesters can be both homopolymers and copolymers. As copolymers In particular, those in addition to recurrent PTMT and / or PBT units still up to 15 mol% based on all Repeating units of polyester repeating units more usual Comonomers, such as. Example, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-cyclohexanedimethanol, Polyethylene glycol, isophthalic acid and / or adipic acid, contain. In the context of the present invention, however, polyester homopolymers prefers.

The polyesters according to the invention can be customary amounts other additives than admixtures, such as catalysts, stabilizers, Antistatic agents, antioxidants, flame retardants, dyes, dye-uptake modifiers, Light stabilizers, organic phosphites, optical brighteners and Matting agents included. Preferably, the polyesters contain 0 to 5 wt .-% based on the total weight of the filament of additives.

Furthermore, the polyesters can also a small proportion, preferably up to 0.5 wt .-% based on the total weight of the filament, on Branching components, included. To the inventively preferred Branching components include polyfunctional acids, such as Trimellitic acid, pyromellitic acid, or tri- to hexavalent alcohols, such as Trimethylolpropane, pentaerythritol, dipentaerythritol, glycerol, or the like Hydroxy acids.

1. Ein Copolymer, welches folgende Monomereinheiten enthält:

A =

Acrylsäure, Methacrylsäure oder CH₂ = CR - COOR', wobei R ein H-Atom oder eine CH₃-Gruppe und R' ein C_1-15-Alkylrest oder ein C_5-12-Cycloalkylrest oder ein C_6-14-Arylrest ist,

B =

Styrol oder C_1-3-alkylsubstituierte Styrole,

wobei das Copolymer aus 60 bis 98 Gew.-% A und 2 bis 40 Gew.-% B, vorzugsweise aus 83 bis 98 Gew.-% A und 2 bis 17 Gew.-% B, und besonders bevorzugt aus 90 bis 98 Gew. -% A und 2 bis 10 Gew.-% B (Summe = 100 Gew.-%) besteht.

2. Ein Copolymer, welches folgende Monomereinheiten enthält:

C =

Styrol oder C_1-3-alkylsubstituierte Styrole,

D =

eines oder mehrere Monomere der Formel I, II oder III

wobei R¹, R² und R³ jeweils ein H-Atom oder ein C_1-15-Alkylrest oder ein C_6-14-Arylrest oder ein C_5-12-Cycloalkylrest sind,

wobei das Copolymer aus 15 bis 95 Gew.-% C und 2 bis 80 Gew.-% D, vorzugsweise aus 50 bis 90 Gew.-% C und 10 bis 50 Gew.-% D und besonders bevorzugt aus 70 bis 85 -% C und 15 bis 30 Gew.-% D besteht, wobei die Summe aus C und D zusammen 100 Gew.-% ergibt.

3. Ein Copolymer, welches folgende Monomereinheiten enthält:

E =

Acrylsäure, Methacrylsäure oder CH₂ = CR - COOR', wobei R ein H-Atom oder eine CH₃-Gruppe und R' ein C_1-15-Alkylrest oder ein C_5-12Cycloalkylrest oder ein C_6-14-Arylrest ist,

F =

Styrol oder C_1-3-alkylsubstitutierte Styrole,

G =

eines oder mehrere Monomere der Formel I, II oder III

wobei R¹, R² und R³ jeweils ein H-Atom oder ein C_1-15-Alkylrest oder ein C_5-12-Cycloalkylrest oder ein C_6-14-Arylrest sind,

H =

eines oder mehrerer etyhlenisch ungesättigter mit E und/oder mit F und/oder G copolymerisierbarer Monomerer aus der Gruppe, welche aus α-Methylstyrol, Vinylacetat, Acrylsäureestern, Methacrylsäureestern, die von E verschieden sind, Vinylchlorid, Vinylidenchlorid, halogensubstituierten Styrolen, Vinylethem, Isopropenylethern und Dienen besteht,

wobei das Copolymer aus 30 bis 99 Gew.-% E, 0 bis 50 Gew.-% F, >0 bis 50 Gew.-% G und 0 bis 50 Gew.-% H, vorzugsweise aus 45 bis 97 Gew.-% E, 0 bis 30 Gew.-% F, 3 bis 40 Gew.-% G und 0 bis 30 Gew.-% H und besonders bevorzugt aus 60 bis 94 Gew.-% E, 0 bis 20 Gew.-% F, 6 bis 30 Gew.-% G und 0 bis 20 Gew.-% H besteht, wobei die Summe aus E, F, G und H zusammen 100 Gew.-% ergibt.

4. Ein Polymer aus folgender Monomereinheit:

wobei R¹ und R² Substituenten bestehend aus den optionalen Atomen C, H, O, S, P und Halogenatomen sind und die Summe des Molekulargewichts von R¹ und R² mindestens 40 beträgt. Beipielhafte Monomereinheiten umfassen Acrylsäure, Methacrylsäure, und CH₂ = CR - COOR', wobei R ein H-Atom oder eine CH₃-Gruppe und R' ein C_1-15-Alkylrest oder ein C_5-12-Cycloalkylrest oder ein C_6-14-Arylrest ist, sowie Styrol und C_1-3alkylsubstituierte Styrole.

In the context of the present invention, 0.05% by weight to 2.5% by weight, based on the total weight of the filament, of additive polymer is added to the PBT and / or PTMT as strain-increasing agent. Particularly suitable additive polymers according to the invention include the following polymers and / or copolymers:

1. A copolymer containing the following monomer units:

A =

Acrylic acid, methacrylic acid or CH ₂ = CR - COOR ', where R is H or CH ₃ and R' is C _1-15 alkyl or C _5-12 cycloalkyl or C _6-14 aryl is

B =

Styrene or C _1-3 alkyl-substituted styrenes,

wherein the copolymer of 60 to 98 wt .-% A and 2 to 40 wt .-% B, preferably from 83 to 98 wt .-% A and 2 to 17 wt .-% B, and particularly preferably from 90 to 98 wt % A and 2 to 10% by weight B (total = 100% by weight).

2. A copolymer containing the following monomer units:

C =

Styrene or C _1-3 alkyl-substituted styrenes,

D =

one or more monomers of the formula I, II or III

wherein R ¹ , R ² and R ^{3 are} each H or C _1-15 alkyl or C _6-14 aryl or C _5-12 cycloalkyl,

wherein the copolymer consists of 15 to 95% by weight C and 2 to 80% by weight D, preferably from 50 to 90% by weight C and 10 to 50% by weight D and particularly preferably from 70 to 85% C and 15 to 30 wt .-% D, wherein the sum of C and D together gives 100 wt .-%.

3. A copolymer containing the following monomer units:

E =

Acrylic acid, methacrylic acid or CH ₂ = CR - COOR ', where R is H or CH ₃ and R' is C _1-15 alkyl or C _5-12 cycloalkyl or C _6-14 aryl .

F =

Styrene or C _1-3 alkyl-substituted styrenes,

G =

one or more monomers of the formula I, II or III

where R ¹ , R ² and R ^{3 are} each an H atom or a C _1-15 -alkyl radical or a C _5-12 -cycloalkyl radical or a C _6-14 -aryl radical,

H =

one or more ethylenically unsaturated monomers copolymerizable with E and / or with F and / or G from the group consisting of α-methylstyrene, vinyl acetate, acrylic acid esters, methacrylates other than E, vinyl chloride, vinylidene chloride, halogen-substituted styrenes, vinyl ethers, isopropenyl ethers and serving,

wherein the copolymer of 30 to 99 wt .-% E, 0 to 50 wt .-% F,> 0 to 50 wt .-% G and 0 to 50 wt .-% H, preferably from 45 to 97 wt .-% E, 0 to 30 wt .-% F, 3 to 40 wt .-% G and 0 to 30 wt .-% H and particularly preferably from 60 to 94 wt .-% E, 0 to 20 wt .-% F, 6 to 30 wt .-% G and 0 to 20 wt .-% H, wherein the sum of E, F, G and H together gives 100 wt .-%.

4. A polymer of the following monomer unit:

wherein R ¹ and R ^{2 are} substituents consisting of the optional atoms C, H, O, S, P and halogen atoms and the sum of the molecular weight of R ¹ and R ^{2 is} at least 40. Exemplary monomer units include acrylic acid, methacrylic acid, and CH ₂ = CR - COOR 'where R is H or CH ₃ and R' is C _1-15 alkyl or C _5-12 cycloalkyl or C _{6 -14} -aryl, as well as styrene and C _1-3 alkyl-substituted styrenes.

Details of the preparation of these substances are disclosed in WO 99/07 927 described.

In the context of the invention are additive polymers and / or copolymers in Fonn of bead polymers particularly preferred whose particle size in a particularly favorable range. Preferably, the invention are for example by mixing into the melt of the fiber polymers using additive polymers and / or copolymers in the form of particles with an average diameter of 0.1 to 1.0 mm. There are, however larger or smaller beads or granules can be used. The additive polymers and / or copolymers may also already be included in chips of the matrix polymer be, so that a metering is omitted.

Furthermore, preference is given to additive polymers and / or copolymers which are amorphous and are insoluble in the polyester matrix. Preferably, they have one Glass transition temperature of 90 to 200 ° C, the glass transition temperature in a known manner, preferably by differential scanning calorimetry, is determined. Further details may be in the state of the art, for example the Publication WO 99/07927, the disclosure of which hereby is explicitly referred to.

Preferably, the additive polymer and / or copolymer is selected such that the ratio of the melt viscosities of the additive polymer and / or Copolymer and the matrix polymer 0.8: 1 to 10: 1, preferably 1.5: 1 to 8: 1 is. The melt viscosity is in a known manner by means of Oscillation Rheometer at an oscillation frequency of 2.4 Hz and a Temperature equal to the melting temperature of the matrix polymer plus 28 ° C is, measured. For PTMT, the measurement temperature for the melt viscosity is included 255 ° C. Further details can in turn be found in document WO 99/07927 be removed. The melt viscosity of the additive polymer and / or Copolymer is preferably higher than that of the matrix polymer and it has shown that the choice of a specific viscosity range for the additive polymer and / or copolymer and the choice of the viscosity ratio to Optimization of the properties of the yarn produced contributes. At a optimized viscosity ratio is a minimization of the amount of additive Additive polymer and / or copolymer possible, whereby, inter alia, the Profitability of the method is improved. The to be spun Polymer mixture preferably contains 0.05 to 2.5 wt .-%, especially preferably 0.25 to 2.0 wt .-% additive polymer and / or copolymer.

By choosing the favorable viscosity ratio to achieve a close Distribution of particle sizes of the additive polymer and / or copolymer in the Polymer matrix with the desired fibril structure of the additive polymer and / or copolymer in the thread. The high compared to the matrix polymer Glass transition temperature of the additive polymer and / or copolymer provides a rapid solidification of this fibril structure in the filament safely. The maximum particle sizes of the additive polymer and / or copolymer immediately after exiting the spinneret at about 1000 nm, while the average particle size is 400 nm or less. After the spinning delay of the Thread reaches the favorable Fibrillenstruktur, in which the threads at least 60 wt .-% of the additive polymer and / or copolymer in the form of fibrils with Lengths in the range of 0.5 to 20 microns and diameters ranging from 0.01 to 0.5 microns included.

The usable according to the invention polyesters are preferably thermoformable and can be spun into filaments and spooled become. In this case, such polyesters are particularly advantageous, the one Intrinsic viscosity in the range of 0.70 dl / g to 0.95 dl / g.

A polymer melt, for example, directly from the Endreaktor a Polycondensation be removed or from solid polymer chips in a melt extruder are made,

The spin additive can in known manner, inter alia, in molten or solid form metered into the matrix polymer, homogeneously distributed in this and to fine particles are dispersed. Advantageously, a device may be used according to DE 100 22 889.

In the method according to the invention, the melt or melt mixture the polyester by means of spinning pumps at a constant speed, the speed is set according to known formula, that the desired yarn titer is obtained, pressed into nozzle packages and through the nozzle holes of the nozzle plate of the package is extruded into molten filaments.

The melt can be made for example in an extruder of polymer chips are, where it is particularly favorable, the chips previously on a water content ≤ 30 ppm, in particular to a water content of ≤ 15 ppm.

T_m:

Schmelzpunkt des Polyesters [°C]

T_Sp:

Spinntemperatur [°C].

The temperature of the melt, which is commonly referred to as the spinning temperature and measured in front of the spinning pump, depends on the melting point of the polymer used or the polymer mixture used. It is preferably in the range given by formula 1: Formula 1: T m + 15 ° C ≤ T sp ≤ T m + 45 ° C With

T _m:

Melting point of the polyester [° C]

T _Sp :

Spinning temperature [° C].

The specified parameters serve to limit the hydrolytic and / or thermal viscosity degradation, the expediently as possible should be low. In the context of the present invention is a viscosity reduction less than 0.12 dl / g, in particular less than 0.08 dl / g, desirable.

The homogeneity of the melt has a direct influence on the Material properties of the spun filaments. Preferably used therefore a static mixer with at least one element, which after the Spinning pump is installed, for homogenization of the melt.

The temperature dependent on the spinning temperature of the nozzle plate is through regulated their so-called heat tracing. Come as a heat For example, a "Diphyl" heated spinning beam or additional Convection or radiant heater in question. Usually the temperature is the nozzle plates at the level of spinning temperature.

A temperature increase at the nozzle plate can be achieved by the pressure gradient in the nozzle package. Known derivations, such as K. Riggert "Advances in the production of polyester tire cord" Chemiefasern 21 , page 379 (1971), describe a temperature increase of about 4 ° C per 100 bar pressure drop.

Furthermore, it is possible to increase the nozzle pressure by using loose filter media, in particular of steel sand with a mean grain size between 0.10 mm and 1.2 mm, preferably between 0.12 mm and 0.75 mm and / or filter blanks, the made of metal fabrics or non-wovens with a fineness ≤ 40 μ can control.

In addition, the pressure drop in the nozzle hole contributes to the total pressure. Of the Nozzle pressure is preferably between 80 bar and 450 bar, in particular set between 100 bar and 250 bar.

δ:

Dichte der Schmelze [g/cm³]; für PTMT = 1,12 g/cm³

D:

Düsenlochdurchmesser [cm]

dpf:

Titer des Einzelfilamentes [den]

The spinning distortion i _Sp , ie the quotient of take-off speed and injection speed, is calculated according to US Pat. No. 5,250,245 via formula 2 with the density of the polymer or polymer mixture, the nozzle hole diameter and the titer of the single filament: Formula 2: i sp = 2.25 • 10 5 • (δ • π) • D 2 (Cm) / dpf (denier) With

δ:

Density of the melt [g / cm ³ ]; for PTMT = 1.12 g / cm ³

D:

Nozzle hole diameter [cm]

dpf:

Titre of the individual filament

In the context of the present invention, the spinning delay is between 70 and 500, preferably between 100 and 250.

The length / diameter ratio of the nozzle hole is preferably between 1.5 and 6 selected, in particular between 1.5 and 4.

The extruded filaments pass through a cooling delay zone.
Directly below the nozzle package this is designed as a return zone in which the emerging from the nozzle holes filaments are preserved from the direct action of the cooling gas and delayed in delay or cooling. An active part of the return is performed as an offset of the nozzle package in the spinning beam in, so that the filaments are surrounded by heated walls. A passive part is formed by insulation layers and unheated frames. The lengths of the active recess are between 0 to 100 mm, that of the passive part between 20 to 120 mm, with a total length of 30 - 200 mm, preferably 30 - 120 mm is maintained.

As an alternative to the active recess may be below the spinner Be installed reheater. In contrast to the active return points then this zone of cylindrical or rectangular cross section at least a heating independent of the spinning beam.

For radial, the thread concentrically surrounding porous cooling systems can the cooling delay achieved by means of cylindrical covers become.

Subsequently, the filaments are at temperatures below their Solidification temperature cooled. According to the invention denotes the Solidification temperature is the temperature at which the melt in the solid State of aggregation passes.

In the context of the present invention, it has proven to be particularly useful proved to cool the filaments to a temperature at which they in essential are no longer sticky. Particularly advantageous is a cooling the filaments to temperatures below their crystallization temperature, in particular to temperatures which are below their glass transition temperature.

Means for cooling the filaments are those skilled in the art from the Technique known. The use has proven particularly useful according to the invention of cooling gases, in particular cooled air. The cooling air points preferably a temperature of 12 ° C to 35 ° C, especially 16 ° C to 26 ° C. on. The speed of the cooling air is advantageously in the range of 0.20 m / sec to 0.55 m / sec.

For example, monofilament systems can be used to cool the filaments used, consisting of individual cooling tubes with perforated wall consist. Through active cooling air supply or by using the Self-priming effect of the filaments becomes a cooling each achieved single filament. Alternative to the single tubes are also the known Querstromanblasungssysteme used.

A special embodiment of the cooling and drafting area exists therein, the filaments emerging from the retarding zone in a zone of the Length in the range of 10 to 175 cm, preferably in a zone of length in Range of 10 - 80 cm to supply cooling air. It is for filaments with a Titer when winding ≤ 1.5 dtex per filament a zone length in the range of 10 - 40 cm and for filaments with a titer between 1.5 and 9.0 dtex per Filament a zone length in the range of 20 - 80 cm particularly suitable. it then the filaments and their accompanying air through a cross-section reduced channel passed together, being controlled by the Cross-sectional tapering and dimensioning in the thread running direction Ratio of air to yarn speed when peeling from 0.2 to 20: 1, preferably 0.4 to 5: 1, is set.

After cooling the filaments to temperatures below the Solidification temperature, they are bundled into a thread. Of the According to the invention suitable distance of the bundling of the nozzle bottom can by methods known to those skilled in the art for online measurement of Thread speed and / or thread temperature, for example with a Laser Doppler anemometer from TSI / D or an infrared camera of the company Manufacturer Goratec / D type IRRIS 160, to be determined. He is 500 to 2500 mm, preferably 500 to 1800 mm. This filaments are with a Titer ≤ 3.5 dtex, preferably at a smaller distance ≤ 1500 mm, thicker Filaments are preferably bundled at a greater distance.

In the context of the present invention, it is expedient that preferably all Surfaces that come into contact with the spun filament from particularly low-friction materials are made. In this way linting can be largely avoided, it will be higher quality Obtained filaments. As especially suitable for this purpose low-friction surfaces of the specification "TriboFil" from the company Ceramtec / D proven.

The bundling of the filaments takes place in an oiler stone, the thread the the desired amount of spin finish uniformly. A special suitable Ölerstein is characterized by an inlet part, the thread channel with oil inlet opening and the outlet part. The inlet part is funnel-shaped extended so that contact with the still-dry filaments avoided becomes. The impact point of the filaments takes place within the thread channel the inflow of the preparation. Thread channel and oil inlet opening are in the Width adapted to the thread titer and the number of filaments. Particularly well proven have openings and widths in the range of 1.0 mm to 4.0 mm. Of the Outlet part of the oiler is designed as a homogenization distance, the preferably has oil reservoirs. Such oilers can, for example, from the Company Cermatec / D or Goulston / USA.

The uniformity of the oil application can according to the invention of great importance be. It can, for example, with a Rossa meter according to the in Chemical fibers / textile industry, 42./94, Nov. 1992 on page 896 described Method to be determined. Preferably, in such Procedure Values for the standard deviation of the oil longer of less obtained as 90 digits, in particular less than 60 digits. According to the invention Particular preference is given to values for the standard deviation of the oil application less than 45 digits, in particular less than 30 digits. there corresponds to a value for the standard deviation of 90 digits or 45 digits about 6.2% and 3.1% of the coefficient of variation, respectively.

In the context of the present invention, it has proven to be particularly advantageous proved self-degassing lines and pumps to avoid gas bubbles interpreted, as these can lead to a significant oil application fluctuation.

According to the invention, an entangling is particularly preferred before being wound up Thread. Here are nozzles with closed yarn channels as special proved suitable, since in such systems entanglements of the thread in the Insertion slot avoided even with low thread tension and high air pressure become. The Entanglingdüsen are preferably between godets arranged, wherein the exit thread tension by means of different Speed of the inlet and outlet galette is regulated. It should be .20 cN / dtex and primarily values between 0.05 cN / dtex and 0.15 cN / dtex. The air pressure of Entanglingluft is between 0.5 and 5.5 bar, at winding speeds up to 3500 m / min at a maximum of 3.0 bar.

Preferably, node numbers of at least 10 n / m are set. there are maximum opening lengths less than 100 cm and values for the Coefficients of variation of the number of nodes below 100% of particular Interest. Advantageously, when using air pressures above 1.0 bar nodal numbers ≥ 15 n / m achieved by a high uniformity characterized in that the coefficient of variation is less than or equal to 70% and the maximum opening length is 50 cm. In practice, systems have become of the type LD of the company Temco / D, the double system of the company Slack & Parr / USA, or nozzles of the type Polyjet of Heberlein as proved particularly suitable.

The peripheral speed of the first godet unit is called Discharge speed called. Other godet systems can be used be before the thread in the winding unit to winding bodies (coils) on Sleeves is wound up.

Stable, error-free filament wound bodies are a prerequisite for error-free removal of the thread and for as error-free as possible Further processing. Therefore, in the context of the present process, a Winding tension in the range of 0.025 cN / dtex - 0.15 cN / dtex, preferably in Range of 0.03 cN / dtex - 0.08 cN / dtex.

An important parameter of the inventive method is the setting of Thread tension before and between the withdrawal godets. As is known, it is this voltage essentially from the actual orientation voltage Hamana, the friction tension on the yarn guides and the oiler and the Thread-air friction tension together. In the context of the present Invention is the thread tension before and between the withdrawal godets in Range from 0.05 cN / dtex to 0.20 cN / dtex, preferably between 0.08 cN / dtex and 0.15 cN / dtex.

Too low a tension below 0.05 cN / dtex will no longer give the desired level of preorientation. If the stress exceeds 0.20 cN / dtex, then This voltage releases a memory effect when winding and storing the coils out, which leads to the deterioration of the thread characteristics.

According to the invention, the tension is determined by the oiler distance from the nozzle, the Friction surfaces and the length of the distance between oiler and withdrawal godet regulated. This route length is advantageously not more than 6.0 m, preferably less than 2.0 m, with the spinning and drawing machine are arranged by parallel construction such that a straight yarn path is guaranteed.

The geometric parameters also change the conditioning time of the thread between bundling point and Aufspulung described. The fast-running Relaxation during this time affects the quality of the coil construction. Preferably, the conditioning time defined in this way is between 50 and 200 ms selected.

The winding speed of the POYs is between 2200 according to the invention m / min and 6000 m / min. Preferably, a speed between 2500 m / min and 6000 m / min. Particularly preferred are the Polymer blends at speeds in the range of 3500 m / min to 6000 wound up in m / min.

Advantageously, during the implementation of the inventive Method in the vicinity of the thread winding a temperature ≤ 45 ° C, especially between 12 and 35 ° C, and a relative humidity of 40 - 85% set. Furthermore, it is expedient the POY coils at least 4 hours at 12 to 35 ° C and a relative humidity of 40-85% before Store further processing.

a) eine Reißdehnung zwischen 90 und 165 %, vorzugsweise zwischen 90 und 135 %

b) einen Kochschrumpf von mindestens 30 %, vorzugsweise ≥ 40%,

c) einen Normal-Uster unterhalb von 1,1 %, vorzugsweise kleiner 0,9 %,

d) eine Doppelbrechung zwischen 0,030 und 0,058,

e) eine Dichte kleiner 1,35 g/cm³, vorzugsweise kleiner 1,33 g/cm³,

f) einen Variationskoeffizienten der Reißlast ≤ 4,5 %, vorzugsweise ≤ 2,5 % und

g) einen Variationskoeffizienten der Reißdehnung ≤ 4,5 %, vorzugsweise ≤ 2,5 % auf.

The filament of the invention has after 4 weeks storage under normal conditions

a) an elongation at break between 90 and 165%, preferably between 90 and 135%

b) a boiling shrinkage of at least 30%, preferably ≥ 40%,

c) a normal Uster below 1.1%, preferably below 0.9%,

d) a birefringence between 0.030 and 0.058,

e) a density of less than 1.35 g / cm ³ , preferably less than 1.33 g / cm ³ ,

f) a coefficient of variation of the breaking load ≤ 4.5%, preferably ≤ 2.5% and

g) a coefficient of variation of the elongation at break ≤ 4.5%, preferably ≤ 2.5%.

The term "normal conditions" is known to those skilled in and over the Standard DIN 53802 defined. Under "normal conditions" according to DIN 53802 the temperature is 20 ± 2 ° C and the relative humidity 65 ± 2%.

In addition, it is particular in the context of the present invention advantageous in that the boiling shrinkage measured directly after being wound up between 50 and 65% and after 4 weeks storage under normal conditions at least 30%, preferably ≥ 40%. Surprisingly, it has become have shown that POY coils produced in this way are excellent for further processing to let.

Method for determining the specified material parameters are the Professional well known. They can be taken from the specialist literature. Although most parameters are determined in different ways In the context of the present invention, the following methods for determining the filament characteristics as particularly useful:

The intrinsic viscosity is in the capillary viscometer from Ubbelohde at 25 ° C and calculated according to known formula. As a solvent is a Mixture of phenol / 1,2-dichlorobenzene in the weight ratio 3: 2 used. The Concentration of the solution is 0.5 g of polyester per 100 ml of solution.

To determine the melting point, the crystallization and the glass transition temperature a calorimeter DSC device from Mettler is used. Here is the Sample first heated to 280 ° C and melted and then quenched. The DSC measurement is carried out in the range of 20 ° C to 280 ° C with a heating rate of 10 K / min. The temperature variables are determined by the processor.

The determination of the density of filaments is carried out in a density-gradient column at a temperature of 23 ± 0.1 ° C. The reagent used is n-heptane (C ₇ H ₁₆ ) and tetrachloromethane (CCl ₄ ). The result of the density measurement can be used to calculate the degree of crystallinity, based on the density of the amorphous polyester D _a and the density of the crystalline polyester D _k . The corresponding calculation is known from the literature, for example for PTMT D _a = 1.295 g / cm ³ and D _k = 1.429 g / cm ³ .

The titer is known with a precision grape and a weighing device in Determined way. The bias is suitably for Preoriented filaments (POYs) 0.05 cN / dtex and for textured yarn (DTY) 0.2 cN / dtex.

Tear strength and elongation at break are included in a Statimat meter the following conditions are determined; the clamping length is 200 mm for POY or 500 mm for DTY, the measuring speed is 2000 mm / min for POY or 1500 mm / min for DTY, the preload is 0.05 cN / dtex for POY or 0.2 cN / dtex for DTY. By dividing the values for the maximum breaking load the titer determines the tear strength and the elongation at break is added evaluated maximum load.

Strands of filaments are used to determine the boiling shrinkage de-energized in water at 95 ± 1 ° C for 10 ± 1 min. The strands are tempered with a bias of 0.05 cN / dtex for POY or 0.2 cN / dtex for DTY produced; the length measurement of the strands before and after the temperature treatment takes place at 0.2 cN / dtex. From the Length difference is calculated in a known manner of boiling shrinkage.

The determination of the birefringence is carried out according to DE 19,519,898 described procedure. Therefore, explicit in this context the disclosure of DE 19,519,898 reference.

The crimp characteristics of the textured filaments are in accordance with DIN 53840, Part 1 with the texturates of the company Stein / D at 120 ° C development temperature measured.

The normal Uster values are determined with the Uster tester 4-CX and as Uster% values indicated. It is at a test speed of 100 m / min the test time 2.5 min.

The POY according to the invention can be further processed in a simple manner, in particular stretch texturized. In the context of the present invention the stretch texturing preferably takes place at a texturing speed of at least 500 m / min, more preferably in one Texturing speed of at least 700 m / min. The draw ratio is preferably at least 1: 1.35, in particular at least 1: 1.40. It has become Stretch texturing on a high temperature heater type machine, such as For example, the AFK the company Barmag, proved to be particularly useful.

The bulky filaments thus produced have a low number Lint and after staining under cooking conditions with a Dispersion dye without carrier excellent color depth and Color uniformity on.

Bulky SET filaments produced according to the invention preferably have a tensile strength of more than 26 cN / tex and an elongation at break of more than 36%. For bulky HE filaments, the without temperature application in one second heaters are available, the tear strength is preferably more than 26 cN / tex and the elongation at break more than 30%.

The bulking and elasticity behavior of the filaments according to the invention is outstanding.

The invention will be explained in more detail by examples, without the invention should be limited to these examples.

Examples 1 to 3 Spinning and winding

PTMT chips with an intrinsic viscosity of 0.93 dl / g, one Melt viscosity of 325 Pa s (measured at 2.4 Hz and 255 ° C), a Melting point of 227 ° C, a crystallization temperature of 72 ° C and a Glass transition temperature of 45 ° C were at a temperature of 130 ° C in dried a tumble dryer to a water content of 11 ppm.

The chips were melted in a 3E4 extruder from Barmag, see above that the temperature of the melt was 255 ° C. This melt was various amounts of polymethyl methacrylate commercial type Plexiglas 7N the company Röhm GmbH / D added as strain increase additive, which previously dried to a residual moisture of less than 0.1%.

The additive polymer was for this purpose by means of a melting extruder melted and with a gear metering pump of the feed device supplied and there by an injection nozzle in the flow direction of the Supplied polyester component. In a static mixer from. Sulzer, type Both 15-element SMX and 15 mm inner diameter SMX were used Melt homogeneously mixed together and finely dispersed.

The melt viscosity of the type Plexiglas 7N was 810 Pa s (2.4 Hz, 255 ° C), whereby the ratio of additive and polyester melt viscosity was 2.5: 1.

The transported amount of melt was 63 g / min with a residence time of 6 min, the dose added by the spin pump to the nozzle pack became such adjusted so that the POY titer was about 102 dtex. There were different Winding speeds set. After the spin pump before entering the Nozzle package was an element static mixer, type HD-CSE with 10 mm Internal diameter of the company Fluitec installed. The trace heating of Product line and spin block containing the pump and nozzle pack, were set at 255 ° C. The nozzle package contained steel sand as filter media the grain size 350-500 microns with a height of 30 mm and a 20 micron Vliesund a 40 μm mesh filter. The melt was passed through a nozzle plate of 80 mm diameter and 34 holes with a diameter of 0.25 mm and extruded a length of 1.0 mm. The nozzle pressure was about 120-140 bar.

The cooling delay zone had a length of 100 mm, with 30 mm heated wall and 70 mm insulation and unheated frame were. The Melt filaments were then subsequently in a blow shaft with Querstromanblasung a blow length of 1500 mm cooled. The cooling air had a speed of 0.35 m / sec, a temperature of 18 ° C and a relative Humidity of 80%. The solidification point of the filaments was at a distance of about 800 mm below the spinneret.

With the help of a thread oiler at a distance of 1050 mm from the nozzle were provided the threads with spin finish and bundled. The oiler was with one TriboFil surface and had an inlet opening of 1 mm Diameter. The applied preparation amount was 0.40% based on the Thread weight.

The bundled thread was then fed to the winding machine. The distance between oiler and first withdrawal godet was 3.2 m. The conditioning time was between 105 and 140 ms. A pair of godets became S-shaped from the thread entwined. Between the godets was a Temco Entanglingdüse installed, which was operated with an air pressure of 1.5 bar. According to the Speed setting was the winding speed of the winder of the type SW6 of the company Barmag adjusted so that the Aufspilladenspannung 5 cN. The indoor climate was at 24 ° C at 60% Relative humidity adjusted so that in the environment of the Filament winding set a temperature of about 34 ° C.

For all additive additions, a significant increase in Productivity achieved. There were 10 kg coils produced, which are easy let loose from the spuldom. The POY game is characterized by a good temporal consistency of the yarn properties over the storage period of 4 weeks at Normal climate according to DIN 53802. The cooking shrinkage was right after the Spinning and reeling in the range of 51-54% determined. The texturability and the staining uniformity obtained was excellent. The applicable Draw ratio was surprisingly high for the POY rates used.

The other parameters and characteristics are summarized in Tables 1 to 4. experimental parameters experimental parameters example 1 Example 2 Example 3 Additive concentration [%] 0.5 0.7 1.0 Withdrawal speed [m / min] 3011 3520 4022 Winding speed [m / min] 3005 3500 4000 spinning draft 183 182 181 thread tensions in front of godets [CN] 13 15.5 16 between godets max [cN] 12 13 12.5 in front of godets [CN / dtex] 0.13 0.15 0.16 between godets max [cN / dtex] 0.11 0.13 0.12 Aufspulfadenspannung [CN] 6.3 5.9 6.4 Aufspulfadenspannung [CN / dtex] 0.062 0.058 0.062 Material properties of the preoriented PTMT filaments material properties example 1 Example 2 Example 3 Titre [dtex] 102 102.5 103 Tear strength [cN / tex] 20.2 21.8 22.3 Elongation at break [%] 132.7 115.4 98.2 Normal Uster [%] 0.80 0.90 0.94 Boiling shrinkage [%] 48 44 38 Birefringence • 10 ³ Δn 36 47 51 Density [g / cm ³ ] 1,315 1,318 1,320 CV tear load [%] 1.7 1.5 2.1 CV elongation at break [%] 1.9 1.9 3.3

drawtexturizing

The PTMT filament coils were exposed to normal climate for four weeks according to DIN 53802 and then a draw texturing machine from Barmag, type FK6-S-900, submitted. The experimental parameters of stretch texturing for Production of so-called SET filaments are shown in Table 3, which Material properties of the resulting bulky SET filaments are in Table 4 summarized.

The texturing errors were detected by UNITENS of the Fima Barmag at the following limit settings: UP / LP = 3.0 cN, UM / LM = 6.0 cN. Experimental parameters of stretch texturing experimental parameters example 1 Example 2 Example 3 Speed [m / min] 700 700 700 draw ratio 1: 1,70 1: 1.60 1: 1.44 D / Y-ratio 2.1 2.1 2.1 Temp. Heater 1 [° C] 155 155 155 Temp. Heater 2 [° C] 160 160 160 Texturing error [n / 10 km] 0 0 0 thread tension F ¹ , in front of aggregate [cN] 17 18 19 F ² , according to aggregate [cN] 19 21 21 F ² -CV [%] 0.78 0.93 0.89 F ² -CV: coefficient of variation of F ² Material properties of the stretch-textured filaments material properties example 1 Example 2 Example 3 Titre [dtex] 67 69 79 Tear strength [cN / tex] 26.9 29.6 28.2 Elongation at break [%] 38.6 37.8 38.0 visual staining assessment evenly evenly evenly Crimp resistance [%] 84 85 79 Crimping [%] 25 24 23

Claims (9)

1. Method for producing and winding pre-orientated polyester filaments of which at least 90% by weight as a percentage of the total weight of the polyester filament comprises polybutylene terephthalate (PBT) and/or polytrimethylene terephthalate (PTMT), and preferably PTMT, characterised in that

   a) the spinline strain is set in the range 70 to 500,

   b) directly after emerging from the spinneret capillary, the filaments pass through a delay zone for cooling from 30 mm to 200 mm in length,

   c) the filaments are cooled to below the solidification temperature,

   d) the filaments are bundled at a distance of between 500 mm and 2500 mm from the underside of the spinneret,

   e) the filament tension is set at between 0.05 cN/dtex and 0.2 cN/dtex upstream of and between the draw-off godets,

   f) the filament is wound at a filament tension of between 0.025 cN/dtex and 0.15 cN/dtex,

   g) the winding speed is set at between 2200 m/min and 6000 m/min

   h) and a polyester is used with which 0.05% by weight to 2.5% by weight, as a percentage of the total weight of the filament, of additive polymer is admixed as an elongation-increasing agent.
2. Method according to claim 1, characterised in that PBT and/or PTMT having a limiting viscosity index in the range from 0.7 dl/g to 0.95 dl/g is used.
3. Method according to claim 1 and/or 2, characterised in that a temperature ≤ 45°C is set in the surroundings of the reel of filament in the winding.
4. Method according to at least one of the foregoing claims, characterised in that the reels of polyester are stored for at least 4 hours at 12 - 35°C and 40 - 85% relative humidity before further processing.
5. Method according to at least one of the foregoing claims, characterised in that the winding speed is set at between 2500 m/min and 6000 m/min.
6. Pre-orientated polyester filaments obtainable by a method according to at least one of the foregoing claims, characterised in that, after 4 weeks' storage under standard conditions under DIN 53802, it has

   a) an elongation at break of between 90% and 165%,

   b) a boiling shrinkage of at least 30%,

   c) a normal uster of below 1.1%,

   d) a birefringence of between 0.030 and 0.058,

   e) a density of less than 1.35 g/cm³ and preferably of less than 1.33 g/cm³,

   f) a coefficient of variation of the breaking strain≤ 4.5% and

   g) a coefficient of variation of the elongation at break≤ 4.5%.
7. Method of producing bulked polyester filaments, characterised in that filaments according to claim 6 are processed into a bulked filament on a draw texturing machine at a speed of at least 500 m/min and a draw ratio of at least 1:1.35.
8. Bulked polyester SET filaments obtainable by a method according to claim 7, characterised in that their tenacity at break is more than 26 cN/tex and their elongation at break is more than 36%.
9. Bulked polyester HE filaments obtainable by a method according to claim 7, characterised in that their tenacity at break is more than 26 cN/tex and their elongation at break is more than 30%.

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