JPS6031923B2 - Highly oriented unstretched polyester filament - Google Patents

Description

[Detailed description of the invention] The present invention has extremely excellent workability in stretch false twisting processing,
Moreover, the present invention relates to highly oriented undrawn polyester filaments that can be used to produce high quality bulky textured yarns.

Polyesters, particularly polyesters mainly composed of polyethylene terephthalate, are widely used because they have excellent properties, and in particular, filaments obtained by melt drawing are widely used.

In recent years, the technology for splicing polyester filaments has progressed, making it possible to produce highly oriented undrawn filaments by spinning at high speeds, and the resulting highly oriented undrawn filaments are generally subjected to drawing and bulk processing as they are. It is subjected to a so-called stretching false twisting process, which is performed sequentially or simultaneously.

However, various troubles occur during such high-speed yarn grading and processing steps.

In other words, in the high-speed yarn process, yarn breakage and curling occur frequently;
In the drawing/false twisting process, wrapping, yarn breakage, fuzz, etc. occur frequently. Particularly recently, as processing speeds have increased, this drawback has also increased. As a method to solve this drawback, a method has been proposed in which solid fine particles are precipitated or blended into the polyester used for high-speed paper yarn.

However, no satisfactory method has yet been found. Namely, Hakama Sekisho 49-11 Milk Rudder No. 5 Publication and Tokuseki Sho 50
Japanese Patent No. 1124 proposes a method in which solid fine particles are precipitated using a catalyst or a phosphorus compound used during the synthesis of polyester.

However, with these methods, foreign matter of the same components as the precipitated fine particles tends to adhere and accumulate on the inner walls and heat transfer surfaces of the equipment used for the polyester synthesis reaction, and this foreign matter sometimes falls off and mixes into the polyester, causing damage to the filter. It has many disadvantages, such as clogging, being mixed into the product and causing yarn breakage, fuzz, etc., and deterioration of product quality. Furthermore, the reaction conditions tend to fluctuate due to foreign matter that adheres and accumulates on the inner walls and heating surfaces of the equipment, making it easy for the quality of the resulting polyester to become uneven.Eventually, the reaction itself becomes difficult, so operations are often stopped for cleaning. , it will be necessary to dismantle and clean it, which will greatly reduce productivity. In addition, process control such as monitoring the accumulation status of attached foreign matter becomes complicated. In addition, Tokuseki Showa 50-12
No. 6 discloses that titanium dioxide having a dispersion value of 10 or less is mixed with 0.
01-3. It has been proposed to subject a highly oriented, drawn polyester filament containing a mixture of .

However, even if such a polyester mixed with titanium dioxide is used, if paper yarn is produced at a high speed of, for example, 3,000 mm/min or more, or the resulting highly oriented undrawn filament is stretched at a high speed of spindle rotation of, for example, 60 rpm or more. When subjected to twisting processing, the occurrence of yarn breakage, wrapping, fuzz, etc. cannot be completely suppressed. It is also possible to solve the above-mentioned drawbacks by selecting an oil agent to be applied to the filaments during the spinning process, but depending on the oil agent, there is a problem that the concentration of the oil agent tends to fluctuate or change in quality during long-term use. The present inventor has conducted extensive research in an effort to eliminate the above-mentioned drawbacks and provide a highly oriented undrawn polyester filament that has excellent workability and is suitable for producing high-quality bulky yarn, and as a result, has identified a specific polyethylene wax. The present invention was achieved based on the finding that the above object can be achieved by incorporating the above-mentioned polyester into the polyester.

That is, the present invention has an average molecular weight of 1000 to 4000 and an oxidized 1
Contains 0.1 to 5% by weight of polyethylene wax of 0 to 50 and has a birefringence of 13 x 10-3 to 80 x 10-3 (
It relates to highly oriented undrawn polyester filaments, preferably 25 x 10-3 to 60 x 10-3).

The polyester mentioned here mainly refers to polyethylene terephthalate, but its terephthalic components and/or
Or a copolymerized polyester in which a part of the ethylene glycol component (usually 20 mol% or less) is replaced with a dicarboxylic component other than the terephthalic acid component, a glycol component other than the ethylene glycol component, an oxycarbon component, or a polyoxyalkylene glycol component. Alternatively, it may be a copolymerized polyester partially containing an amide bond or a urethane bond. Any method can be used to synthesize such polyester.

In the case of polyethylene terephthalate, it is usually produced by subjecting dimethyl terephthalate and ethylene glycol to a transesterification reaction, directly esterifying terephthalic acid and ethylene glycol, or reacting terephthalic acid and ethylene oxide. It is synthesized by a first stage reaction in which a glycol ester of terephthalic acid and/or its low polymer is produced, and then a second stage reaction in which the product of the first stage is subjected to a military condensation reaction. In order to blend polyethylene wax into the polyester obtained in this way, it can be added at any stage before the polyester synthesis reaction is completed, it can be added to the powdered polyester before spinning, or it can be added to the powdered polyester before spinning. Any method may be used, such as adding and blending at times.

The polyethylene wax to be blended has an average molecular weight of 1
000-4000 (preferably 1500-2500),
It has an acid value of 10 to 50 (preferably 15 to 30).

If a polyethylene wax outside this range is used, even if the amount is appropriate, the object of the present invention cannot be achieved. If the amount of polyethylene wax used is too small, it will not be possible to sufficiently improve the processability of the resulting polyester filament, and if it is too large, the processability of the resulting filament will deteriorate, and in particular, yarn breakage will occur frequently. I come to do it. It should be in the range of 0.1 to 5% by weight in the resulting polyester, particularly preferably in the range of 0.2 to 1% by weight. The highly oriented undrawn filament of the present invention, that is, a birefringence of 13 x 10-3 to 80 x 10-3 (preferably 2
An undrawn filament having a diameter of 5 x 10-3 to 60 x 10-3) can be easily produced by spinning the filament at a predetermined spinning speed (take-up speed) using a conventional melt wire method.

This paper yarn speed varies depending on the single filament denier of the filament to be obtained, the temperature of the molten polyester at the time of extrusion, and the cooling conditions at the time of edge extrusion, and cannot be determined unconditionally, but the appropriate filament speed for the desired birefringence can be determined by experience. easily determined. Usually the paper thread speed is in the range 1500 to 4500 m/min (preferably 2500 to 4000 m/min). The highly oriented undrawn polyester filament of the present invention thus obtained has extremely good processability and is suitable for high-speed processing, and its twill yarn is extremely easy to form.

Moreover, there is no need to select a special oil. Incidentally, the highly oriented undrawn filament of the present invention may contain arbitrary additives such as a stabilizer, a heat-resistant agent, a tear-proofing agent, an antioxidant, and an antistatic agent, if necessary. The present invention will be explained in further detail by giving examples below.

In the examples, parts indicate parts by weight, and [knife] is the intrinsic viscosity determined from the value measured at 35 qo in an orthochlorophenol solution. Examples 1-10 Comparative Examples 1-6 Dimethyl terephthalate 10 base, ethylene glycol 7
Manganese acetate 0.08 as base and transesterification catalyst
The mixture was heated under low pressure, and the transesterification reaction took 210 minutes while the generated methanol was removed.

Next, 0.03 part of antimony trioxide as a polycondensation catalyst, 0.04 part of trimethyl phosphate as a stabilizer, and 0.5 part of titanium oxide as a matting agent were added to the transesterification reaction product, and further, the mixture as shown in Table 1 was added. The amounts of various polyethylene waxes listed in the table were added, the temperature was raised to 280 qo, the pressure inside the system was reduced, and the temperature was reduced to 100 qo at 28,000 qo under a reduced pressure of 0.5 Hg.
Polycondensation reaction was carried out for minutes. The stiffness and softening point of the obtained polyester were as shown in Table 1. This polyester was melt-spun using a paper spinneret having 36 spinning holes with a diameter of 0.3 ribs at a yarn temperature of 290°C and a discharge rate of 55 min/min, and wound onto a bobbin at a winding speed of 3000 m/min. I took it.

The birefringence, friction coefficient, yarn breakage rate during spinning (ratio of the number of bobbins where yarn breakage occurs to the total number of bobbins taken up), and unwinding rate (ratio of the number of bobbins where yarn breakage occurs to the total number of bobbins taken up) of the obtained undrawn filament are determined. Table 1 shows the percentage. The obtained undrawn filament was simultaneously drawn and false-twisted at a draw ratio of 1.55 times, a spindle rotation speed of 800,000 times/min, and a processing speed of 220 threads/min, and then wound onto a bobbin.

The tension ratio of the heating tension (t, ) to the untwisting tension (t2) during processing, the yarn breakage rate (ratio of the number of bobbins where yarn breakage occurs to all the winding bobbins), and the complete winding rate (the ratio of the number of completely wound bobbins to all the winding bobbins) Table 1 shows the percentage. As is clear from Table 1, the processability of the highly oriented undrawn filament according to the present invention is extremely good, and its properties during spinning are also extremely good.

On the other hand, undrawn filaments outside the scope of the present invention have extremely poor processability and paper thread properties. Table 1 Example 11~
12. Comparative Examples 7 to 8 The same procedure as in Example 2 was carried out except that the edge yarn winding speed of Example 2 was changed as shown in Table 2, and the birefringence index of the resulting undrawn yarn was changed.

The results are also shown in Table 2. Table 2

Claims (1)

[Scope of Claims] 1 Contains 0.1 to 5% by weight of polyethylene wax having an average molecular weight of 1000 to 4000 and an acid value of 10 to 50, and has a birefringence of 13 x 10^-^3 to 80 x 10^ -^3 highly oriented undrawn polyester filament. 2 The average molecular weight of the polyethylene wax is 1500 to 2
500 and an acid value of 15 to 30. The highly oriented undrawn polyester filament according to claim 1. 3 Birefringence is 25 x 10^-^3 ~ 60 x 10^-^
3. The highly oriented undrawn polyester filament according to claim 1, which is No. 3.