JPS6215325A - Production of polyester fiber - Google Patents

Abstract

PURPOSE:To produce the titled fibers without defects stably for a long period, by stirring fine inert inorganic particles having a specific particle diameter with particles having a large particle diameter in a solvent, separating the large particles, adding the resultant slurry to produce a polymer and melt spinning and resultant polymer at a high speed. CONSTITUTION:(A) Fine inert particles having <=2mu average primary particle diameter are stirred with (B) particles having an average primary particle diameter of 10-4,000 times based on the average primary particle diameter of the component (A) and <=0.5mm average particle diameter in a solvent, and the particles of the component (B) are separated to give a slurry of the particles of the component (A), which are then added to a reaction system for polyester production to prepare the polyester. The resultant polyester is then filtered through a filter having <=20mu absolute filtration diameter in a spinning pack 1, melt spun at >=5,000m/min spinning speed, passed through a quench stack 3 and oiling device 4 and godet rolls 5 and 5' and then wound by a winder 6 to afford the aimed fibers.

Description

Detailed Description of the Invention [Technical Field] The present invention is directed to the production of polyester fibers containing inorganic fine particles in a length of 5000 m.
The present invention relates to a method of obtaining the present invention by melt spinning at an ultra-high speed of 1 minute or more. More specifically, the present invention relates to a method for obtaining ultrahigh-speed spun yarn without yarn breakage, little increase in pack internal pressure, stable spinning for a long period of time, and no defects when performing ultrahigh-speed spinning at 5000 m/min or more.

[Prior art and its problems] Polyester is generally spun by adding inorganic fine particles, mainly titanium oxide, depending on the purpose. When such polyester is melt-spun, it is generally carried out at a spinning speed of 1,000 to 3,500 m/min, and at this speed, spinnability is stable and a uniform yarn can be obtained.
It will be done.

On the other hand, spinning speeds have been increasing rapidly in recent years.
Along with this, high-speed spinning technology has also made great progress, but when the spinning speed exceeds 5000 m/min, yarn breakage or single yarn breakage suddenly begins to occur during spinning, making stable spinning impossible. This is the current situation. For this reason, the high productivity benefits of ultra-high speed spinning are not fully utilized. To solve this problem, for example, US Pat. No. 4,134.882 proposes a spinning method that reduces the radial orientation distribution of the discharged yarn.

In addition, Japanese Patent Application Laid-open No. 56-96913 proposes a method of suppressing crystallization during molecular orientation during ultrahigh-speed spinning in order to suppress yarn breakage, but even if these methods of suppressing crystallization are used, The reality is that stable spinning results cannot be obtained at the scale of industrial production processes. Furthermore, the resulting ultra-high speed spun yarn has defects such as voids and cracks, which adversely affect the physical properties of the yarn, and these problems have not been resolved.

On the other hand, in order to suppress yarn breakage during ultra-high speed spinning,
When filtration is carried out in a specific pack as shown in Publication No. 1712, an improvement effect can be recognized, but the internal pressure of the pack at the start of spinning increases, and the increase in internal pressure over time is also large, which shortens the pack life. The current situation is that fatal problems such as shortening have not been sufficiently resolved.

The present inventors have continued to earnestly study the causes of the above-mentioned problems in ultra-high speed spinning of polyester containing inorganic fine particles.
As a result, it was found that: 1. The size and dispersion state of the inorganic fine particles added to the polymer are greatly related to yarn breakage and voids or crack-like defects that occur during ultra-high speed spinning. 2. The inorganic fine particles added to the polymer It was discovered that the large serrations and the state of dispersion are closely related to the increase in pack internal pressure during spinning, and the present invention was achieved.

[Purpose of the Invention] The present invention aims to produce a polyester containing inorganic fine particles that can be spun stably for a long period of time without yarn breakage, with little increase in the internal pressure of the spinning pack, and without defects when spinning polyester containing inorganic fine particles at ultra high speeds of 5,000 m/min or higher. The purpose is to obtain high-speed spun yarn.

[Structure of the Invention] The object of the present invention is to produce polyester fibers using inert inorganic fine particles (with an average primary particle diameter of 2μ or less).
A> is inorganic fine particles (1 of the average primary particle diameter of A>) in a solvent.
It has a diameter of 0 to 4000 times and the average particle diameter is 0.5 m.
m or less particles (B), and then the particles (
The polyester obtained by adding the slurry of inorganic fine particles (A>) obtained by separating B) to the polyester production reaction system is passed through a filter with an absolute diameter of 20 μm or less in a spinning pack, and then heated at a speed of 5000 m/min or more. This is achieved by a polyester fiber production method characterized by melt spinning at a spinning speed of .

The present invention will be explained in detail below.

One of the important constituent elements of the present invention lies in the regulation of the method for dispersing the inorganic fine particles added in the manufacturing process of the polymer to be subjected to ultra-high speed spinning. In other words, ■ inert inorganic fine particles with an average primary particle size of 2 μ or less (A>) and ■ inorganic fine particles (10 to 4000 of the average primary particle size of A>)
It is essential to use an inorganic fine particle slurry obtained by stirring together with particles having twice the diameter and an average particle diameter of 0.5 mm or less, and then separating the particles (B).

Another important component of the present invention is that the inorganic fine particle slurry obtained by the above method is added to a polyester production system, and 1 q of polyester is filtered in a melt-spinning pack using a filter with an absolute diameter of 20 μm or less. The point is that ultra-high speed spinning is performed at 5000 m/min or more.

The average primary particle diameter of the inert inorganic fine particles (A>) used in the present invention must be 2μ or less, preferably 1μ or less,
More preferably, it is 0.7μ or less, but if it is 2μ or less during synthesis, it can be used as is.

On the other hand, in the case of a synthetic inorganic compound or a natural inorganic compound having a particle size larger than 2μ, it is used after being crushed and classified in advance so that the average primary particle size is 2μ or less.

If the average primary particle diameter is larger than 2 μm, fiber breakage occurs during spinning, defects such as cracks and voids occur in the system, and the internal pressure of the spinning pack increases, which is undesirable.

The average particle diameter of the particles (B) of the present invention is the inert inorganic fine particles (
It is necessary that the average primary particle diameter of A) is 10 to 4000 times, and Q is 5 mm or less. Preferably 1
Particles with a particle size of 5 to 3000 times, more preferably 20 to 2000 times, are used, and the particle size of particle (B) is 0.3 m.
Preferably, r is 71 or less, more preferably 0.1 mm or less.

The average particle diameter of the particles (B) of the present invention is the inert inorganic fine particles (
If the average primary particle diameter of A) is smaller than 10 times, it will be difficult to separate it from the slurry, while if it is larger than 4000 times, or even if it is smaller than 4000 times, Q, if it exceeds 5 mm, the dispersion efficiency will decrease. is insufficient and the agglomeration cannot be broken down.

Metal oxides such as alumina and zirconia, kaolinite,
Inorganic compounds such as oxides such as talc and zeolite, carbonates such as calcium carbonate, phosphates such as lithium phosphate and calcium phosphate, and sulfates such as calcium sulfate and barium sulfate, with an average primary particle size of 2μ or less. say. Among the planar inorganic compounds, titanium dioxide, kaolinite, tar, calcium carbonate, and barium sulfate are particularly preferred.

As the particles (B), particles of ceramics such as alumina and zirconia, glass, steel, etc. are used. Among these, ceramic and glass small spheres are preferred.

In the present invention, the effect of the present invention is further exhibited when a dispersant (C), which will be described later, is used in combination with the slurry consisting of inert inorganic fine particles (A> and (B>).

As the dispersant (C), a phosphorus compound and ammonia or a lower amine compound are used.

Preferred phosphorus compounds include phosphoric acid, phosphorous acid, phosphonic acid, and partial ester compounds thereof; specifically, phosphoric acid, phosphorous acid, phosphoric acid monoethyl ester, phosphoric acid methylethyl ester, phosphoric acid Dibutyl ester, methylphosphonic acid, phenylphosphonic acid, monomethyl ester, etc. can be mentioned. Of course, two or more of these phosphorus compounds may be used in combination. Among these, phosphoric acid, phosphorous acid, and acidic phosphoric acid esters are particularly preferred. Ammonia or lower amine compound has the general formula R+ R2R3R4N or R1R2R3R4N+X″″
(In the formula, R1 to R4 are a hydrogen group or a lower alkyl group of C5 or less, and X- is a counter ion such as water vI or halogen.) A primary to quaternary amine compound is used, and specifically, ammonia, Mention may be made of methylamine, methylethylamine, triethylamine, tetraethylammonium hydride, and dimethylpropylamine. Of course, two or more of these ammonia or lower amine compounds may be used in combination. Particularly preferred ammonia or lower amine compounds are tertiary amines and quaternary ammonium compounds. It is preferable that the number of carbon atoms in the alkyl group is 5 or less in terms of coloring of the polymer during polymerization. The phosphorus compound and ammonia or lower amine compound may be added separately or simultaneously during slurry preparation, or it is preferable to mix them in a suitable solvent in advance and then add them. The preferred molar ratio of phosphorus compound/ammonia or lower amine compound is from 5/1 to 115, more preferably from 2/1 to 1/4, and most preferably from 1/1 to 1/3. If the molar ratio is outside the above range, the dispersion effect will be insufficient and the particles will tend to aggregate again in the polymer. The amount of the dispersant added is preferably 1/1 to 0.0001/1, more preferably 0, as the total of the phosphorus compound and ammonia or lower amine compound, based on the weight ratio of the inorganic fine particles used.
．． 5/1 to 0.001/1, most preferably 0.3/1
~0.01/1. The weight ratio of the dispersant added layer is 1/
When the amount is more than 1, the polymerization rate tends to decrease and the amount of diethylene glycol by-produced increases;
When the ratio is less than /1, the effect of improving dispersibility is small.

Examples of the slurry solvent used in the present invention include water, alcohols such as methanol, ethanol, and ethylene glycol, and hydrocarbons such as toluene, xylene, and pentane. It is particularly preferable to use the same glycol as the one used as the raw material for producing polyester, since this will cause less deterioration in the quality of the polymer and will also prevent contamination during the process and facilitate spinning and operations.

The stirring treatment can be carried out using a conventional stirring device, although it varies depending on the type of inert inorganic fine particles (A) used, the average primary particle size, and the type and size of the particles (B) used together.

That is, a plate stirring device equipped with one or more smoothing blades such as propeller blades, paddle blades, turbine blades, cross blade discs, etc., preferably at 100-10°ooorpm, more preferably for 5 minutes to 10 hours. More preferably, stirring is carried out for 30 minutes to 8 hours.

The dispersion method may be continuous processing or batch processing, but batch processing is more preferable.

The slurry that has been subjected to the stirring treatment of the present invention) - Separate the particles (B) by filtration, decantation, or other methods, and use it as it is, or reuse the slurry; After removing it, it is added to the polynistil production reaction system.

The inorganic fine particle glycol slurry of the present invention can be added at any point in the polyester manufacturing process. Preferably, the intrinsic viscosity of the polymer is 0 from before the start of the esterification or transesterification reaction to the start of the polycondensation reaction, that is, during the polymerization reaction.
．． Added at no more than 2 times. In order to fully exhibit the effects of the present invention, the addition port of the inert fine particles (A) of the present invention must be 5.0% by weight based on the resulting polymer after the polymerization reaction.
It is preferable to add the following mother.

Furthermore, the polyester referred to in the present invention may be any material as long as it is mainly composed of polyester that can be molded into fibers, such as polyethylene terephthalate, poly-1,4-cyclohexylene dimethylene terephthalate, polytetra Methylene terephthalate, polyethylene 2.6-naphthalene dicarboxylate, polyethylene-α,β-bis(2-chlorophenoxy)ethane-4,
Examples include 4'-dicarboxylate, etc., but it is a polyester in which a portion other than the main component is replaced with another difunctional carboxylic acid component to the extent that it does not promote aggregation of inorganic fine particles added in the polyester manufacturing process. It may also be a polyester in which part of the ethylene glycol component is replaced with another diol component.

Furthermore, various additives such as dye-facilitating agents, flame retardants, antistatic agents,
It may also be a polyester copolymerized or mixed with a hydrophilic agent if necessary.

In this way, the resulting inert inorganic fine particle-containing polyester is filtered through a filter with an absolute filtration diameter of 20μ or less in a spinning pack, and then ultra-high-speed spinning is performed at a speed of 5000 m/min or more. The problems of high speed spinning are solved. Here, the term "absolute retirement" defined in the present invention refers to the maximum diameter of the glass beads that have passed through the filter media according to the method of JIS-B8356. The absolute filtration diameter in the present invention is 20μ or less, preferably 15μ or less. However, if a filter with a too fine (absolute) filtration diameter of 2 microns is used, the internal pressure of the pack will increase rapidly, which is not preferable. On the other hand, if the filtration is softer than 20μ, even if the inert inorganic fine particle-containing polyester of the present invention is used, fuzz and yarn breakage occur frequently during spinning, resulting in poor spinning, and the object of the present invention cannot be achieved. . Absolute) As a filter with a filtration diameter of 20μ or less,
In particular, fibers made of stainless steel are preferred, and it is more effective that the fibers are nonwoven fabrics. At least one layer of filter within the spinning pack is necessarily or preferably 20μ. Further, it is preferable to configure the pack internal pressure filter so that the absolute filtration diameter is made smaller in order from the upper layer to the lower layer, since the spinning internal pressure can be suppressed more effectively. Also,
It is possible to use a filter with an absolute r of 20μ or less and two layers such as wire mesh P material, powder sintered metal P material, or sand which has been commonly used in the past. However, in the present invention, it is essential to use a filter with an absolute filtration diameter of 20 μm or less in combination with any P material.

Further, in the present invention, the effect is remarkable for yarns with a single yarn denier of 5 d or less, further 2 d or less obtained by ultra-high speed spinning of 5000 m/min or more.

Here, in order to clarify the meaning of the spinning speed of 5000 m/min or more in the present invention, one example of a specific embodiment of the melt spinning process will be described with reference to FIG. 1. The molten polymer is discharged from the pack 1 within the pack housing 2 and becomes yarn. The discharged yarn is cooled and assimilated in a cooling cylinder 3, and oiled in an oil supply device 4, and then transferred to a first Gotei roll (hereinafter referred to as 1st GD) 5 and a second Gotei roll (hereinafter referred to as 2nd GD) that rotate at a spinning speed of 5000 m/min or more. ) 5 before being wound up by a winding machine 6.

As described above, the spinning speed refers to the surface speed of the drive roll (first GD) with which the yarn discharged from the spinneret first contacts, and is not the winding speed. However, when the 10D and 2nd GD are not used, the winding speed becomes the spinning speed.

In addition, in the present invention, so-called direct spinning drawing, etc., in which drawing is performed continuously in the first GD and the second GD, is also applied.

[Effect of the invention] When a specific inorganic fine particle-containing slurry employing the inorganic fine particle dispersion method described in the claims of the present invention is used,
Since the amount of collected particles present in the polymer is extremely small and it is possible to obtain a polyester that is uniformly dispersed, such a polyvarnish is obtained, and the polyester is passed through a filter with an absolute r of 20μ or less in a spinning pack. ) - After performing the filtration, the following effects are exhibited by melt spinning at a spinning speed of 5000 m/min or more.

That is, (1) In ultra-high speed spinning of 5000 m/min or more, it becomes possible to perform stable spinning for a long period of time without yarn breakage or generation of fuzz. This effect is particularly remarkable in the case of fine denier yarns.

(2> Stable spinning at speeds of 5,000 m/min or higher takes advantage of the high productivity of ultra-high-speed spinning, and the yarn obtained by spinning at 5,000 m/min or higher undergoes a drawing process later. Because it can be used as a practical fiber,
It also produces process rationalization benefits. Therefore, it is possible to significantly reduce costs.

(3) Since there is little increase in the internal pressure of the spinning pack, stable spinning can be performed over a long period of time.

(4) Since there are no defects such as voids or cracks in the resulting system, the fibers are highly uniform and the physical properties of the yarn are also improved.

The present invention will be explained in more detail below with reference to Examples.

In addition. The physical properties in the examples were measured as follows.

A, average primary particle diameter Measured using the BET method.

B. Particle size distribution in slurry Measured using a light transmission type centrifugal sedimentation type particle size analyzer (Ryotsu Seisakusho CP-2 model).

C. A small amount of aggregated coarse particles in the polymer was sandwiched between two cover glasses at 280°C.
After melt-pressing and quenching, microscopic observation was performed, and portions where a plurality of primary particles aggregated with each other and the particle size became coarse were determined to be aggregated coarse particles.

The dispersibility of the particles was determined as follows by observing aggregated coarse particles having a size more than four times the average primary particle size present in 1 mm2.

Grade 1: less than 10 aggregated coarse particles with a size more than 4 times the average primary particle size/mm2.

2nd class: 10 aggregated coarse particles with a size more than 4 times the average primary particle size are present at a size of 2 or more and less than 30 particles/mm2.

Grade 3: 30 or more and less than 50 pieces/mm2 of aggregated coarse particles having a size more than 4 times the average primary particle size are present.

Grade 4: 50 or more aggregated coarse particles with a size exceeding 4 times the average primary particle diameter are present.

D. Intrinsic viscosity 0 Measured at 25°C using chlorophenol as a solvent.

E. Absolute filtration diameter J Refers to the maximum particle diameter of glass beads that passed through the filter media by the method of 15-88356.

Example 1 12 parts of titanium dioxide with an average primary particle size of 0.35μ, 0.4 parts of phosphoric acid, 0.4 parts of triethylamine, 100 parts of ethylene glycol, and 1 glass bead with a particle size of 100μ
50 parts were charged into a stirring device equipped with turbine blades, and 25 parts
The mixture was stirred at 0 rpm for 3 hours and 30 minutes. After stirring, 4
The glass beads were separated and removed using a 0.00 mesh wire mesh to obtain ethylene glycol of titanium dioxide.

The average diameter of titanium dioxide in the slurry was 0.4μ.

Meanwhile, 100 parts of dimethyl terephthalate, 65 parts of ethylene glycol, and 0.04 parts of manganese acetate were added.
The transesterification reaction was carried out at 40-240°C. Next, 0.03 parts of antimony trioxide and 3 parts of the titanium dioxide ethylene glycol slurry mentioned above were added, and 250 parts of ethylene glycol slurry of titanium dioxide was added.
The polymerization reaction was carried out at ~290°C under high vacuum, and the intrinsic viscosity was 0.
1q of 62 polymer.

When the dispersion state of particles in the polymer was observed, the number of aggregated coarse particles was 4 pieces/mm2, indicating a good dispersion state. Using the obtained polymer, the spinning temperature was 298°C, the discharge rate per single hole of the spinneret was 11.3 g/min, and the absolute filtration diameter was 10 in the pack.
After passing through a single layer of a filter made of a non-woven fabric of stainless steel fibers of μ, it was melt-spun at a spinning speed of 8200 m/min. As a result, the number of spun yarn breakages per ton of boria was as low as 3, and the pack life was 15 days, allowing stable spinning over a long period of time. Moreover, no voids or cracks were present in the obtained high-speed spun yarn.

Example 2 Melt spinning was carried out at a spinning speed of 8100 m/min in the same manner as in Example 1, except that the type of filter in the spinning pack and the absolute r retirement were changed.

The number of occurrences of fuzz on the guide during the spinning process and the number of occurrences of yarn breakage during spinning were as shown in Table 1.

Levels C, D, and E are of the present invention. Levels A and B are absolute; the filtration diameter is outside the scope of the present invention. As shown in Table 1, level C
, D, and E showed very good spinnability, with little occurrence of fluff or yarn breakage during spinning. Furthermore, E had a smaller increase in pack internal pressure than D.

Example 3 A slurry was prepared in the same manner as in Example 1, except that the average primary particle diameter of titanium dioxide, the average diameter of the glass beads used, and the type and amount of dispersant added were changed as shown in Table 2. Polyethylene terephthalate was synthesized. The obtained polyethylene terephthalate was spun at a spinning temperature of 296°C.
After passing through a filter made of a stainless steel fiber non-woven fabric with a filtration diameter of 20 μm at a discharge rate of ff 12.50/min per single hole of the spinneret and a filtration diameter of 20 μm, melt spinning was performed at a spinning speed of 78001: n/min. Table 2 shows the dispersion state of particles in the polymer, the degree of pack internal pressure increase during spinning, and the number of yarn breaks during spinning.
It was as shown in

In Table 2, level F indicates that the average primary particle diameter of the inert inorganic fine particles (A) is outside the range of the present invention, and level G indicates that the particles (B
) was not used, and in Level H, the particle size of particles (B) was outside the scope of the present invention, so the spinnability was poor in all cases.

On the other hand, levels I and J of the present invention are those in which the average primary particle diameter of the inorganic fine particles (A>) and the particle diameter of the particles (B) are both satisfied, and filtration within the pack is performed within the scope of the present invention. The spinnability of ultra-high-speed spinning has been greatly improved.The increase in pack internal pressure during spinning is small, and the number of yarn breakages is also small, making it possible to spin yarn stably for an extremely long period of time.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of the melt spinning process of the present invention. 1: Pack 2: Pack housing 3: Cooling cylinder 4: Oil supply device 5: 1st GD 5': 2nd GD 6: Winding machine

Claims (3)

[Claims] (1) When producing polyester fibers, inert inorganic fine particles (A) with an average primary particle size of 2 μ or less are 10 to 4000 times the average primary particle size of the inorganic fine particles (A) in a solvent, and particles with an average particle diameter of 0.5 mm or less (B
), and then the particles (B) were separated, and the slurry of inorganic fine particles (A) was added to the polyester production reaction system. After filtration, 5000m/
A method for producing polyester fiber characterized by melt spinning at a spinning speed of 1 minute or more. (2) The method for producing polyester fibers according to claim (1), wherein the filter is a stainless steel fiber. (3) The filter is composed of multiple layers, and at least one
The method for producing polyester fiber according to claim (1), characterized in that the absolute filtration diameter of each layer is 20μ.