JPS626906A - Production of polyester fiber - Google Patents

Abstract

PURPOSE:To obtain the titled fibers with good stability without causing yarn breakage, by mixing inert organic fine particles having a specific particle diameter with particles having a larger particle diameter and specific disersing agent, separating the above-mentioned particles having the larger particles diameter, producing a polyester in the presence of the resultant slurry and melt spinning the polyester. CONSTITUTION:(A) Inert inorganic particles having <=2mu average primary particle diameter are stirred with (B) particles having a diameter of 10-4,000 times based on the diameter of the component (A) and <=0.5mm average particle diameter and (C) a phosphorus compound and ammonia or a lower amine compound as a dispersing agent in a solvent and, the component (B) is then separated to give a slurry of the component (A), which is then added to a reaction system for producing a polyester and give the polyester. The resultant polyeter is then melted and extruded through a pack 1 in a pack housing 2, quenched and solidified in a quenching stack 3, oiled with an oiling device 4, passed through the first godet roll 5 and the second godet roll 5' and wound by a winder 6 at >=500m/min spinning speed 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 uniform yarns can be obtained.

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 and single yarn breakage suddenly begin to occur during spinning, making stable spinning impossible. This is the current situation. To solve this problem, for example, US Pat. No. 4,134. ' 882@ specification etc. propose a spinning method that reduces the radial orientation distribution of 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, there are problems such as the presence of voids or crack-like defects in the obtained ultra-high speed spun yarn, which have an adverse effect on the physical properties of the yarn, and these problems have not been solved.

On the other hand, in order to suppress yarn breakage during ultra-high speed spinning,
(within certain packs, such as those shown in Publication No. 1712)
Although the improvement effect can be recognized by implementing filtration,
At present, fatal problems such as an increase in the internal pressure of the pack at the start of spinning, a large increase in the internal pressure over time, and a shortening of the pack life have not been sufficiently resolved.

The inventors of the present invention have continued to study the causes of the above-mentioned problems in ultra-high speed spinning using polyester containing inorganic fine particles, and have found that: (1) large serrations and dispersion of the inorganic fine particles added to the polymer can cause yarn breakage and This is largely related to voids or crack-like defects that occur during ultra-high-speed spinning. ■Specific particle dispersants used in the particle slurry process are closely related to the dispersion state of inorganic fine particles added to the polymer, or the increase in pack internal pressure during spinning. The present invention was achieved by discovering the following:

[Objective of the Invention] The present invention aims to obtain an ultra-high-speed spun yarn that can be stably spun for a long time without yarn breakage and has no defects when spinning polyester containing inorganic fine particles at an ultra-high speed of 5000 m/min or more. It is the purpose.

[Structure of the Invention] The object of the present invention described above is - When producing polyester fiber, inert inorganic particles (Adz) having an average primary particle size of 2μ or less Inorganic fine particles (A> have a diameter of 10 to 4.OO0 times the average particle diameter of A>, and the average =
#Particles with a particle diameter of 0.5 mm or less (B), dispersant (C)
5000 m /
This is achieved by a method for producing polyester fiber characterized by melt spinning at a spinning speed of 1 minute or more.

The present invention will be explained in detail below.

The most important component of the present invention lies in the definition of a method for dispersing inorganic fine particles in a polymer subjected to ultra-high speed spinning. That is, ■ Inert inorganic fine particles with an average primary particle size of 2μ or less (A>
■ Inorganic fine particles (A> average particle diameter of 10 to 4000
Particles having twice the diameter and an average particle diameter of 0°5 mm or less, (1) a phosphorus compound and ammonia or a lower amine compound as a dispersant (C) are stirred together in a solvent, (2) the particles (B ) is essential to use an inorganic fine particle slurry obtained by separating.

In the present invention, a polyester obtained by adding the inorganic fine particle slurry obtained by the above method to a polyester production system is further used.
Ultra high speed spinning is performed at 00 m/min or more.

The average particle diameter of the inert inorganic fine particles (△) of the present invention is 2
It is necessary to make it less than μ, preferably less than 1μ, more preferably less than 0.7μ, but at the time of synthesis 2
If it is less than μ, 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 particle size is 2μ or less.

If the average primary particle diameter is larger than 2 .mu., it is not preferable because yarn breakage occurs during spinning, defects such as troughs and voids occur in the system, and the internal pressure of the spinning pack increases.

The average diameter of the particles (B) of the present invention is inert inorganic fine particles (A>
is 10 to 4000 times the average primary particle diameter, and 0.
It is necessary that it is 5 mm or less. Preferably 15~
Particles with a particle size of 3000 times, more preferably 20 to 2000 times, are used, and the particle size of particles (B) is preferably 0.3 mm or less, and 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 it is smaller than 10 times the average particle diameter of A>, it will be difficult to separate it from the slurry, while if it is larger than 4000 times or smaller than 40QO times, O,! If it exceeds 5 mm, the dispersion efficiency will be insufficient and the agglomeration cannot be broken down.

Inert inorganic particles of the present invention having an average primary particle diameter of 2 μ or less (
△) refers to metal oxides such as titanium dioxide, silica, alumina, and zirconia, oxides such as kaolinite, talc, and zeolite, carbonates such as calcium carbonate, phosphates such as lithium phosphate, and calcium phosphate, and F7A acid. Average - for inorganic compounds such as sulfates such as calcium and barium sulfate
Refers to particles with a secondary particle diameter of 2μ or less. Among the inorganic compounds, titanium dioxide, kaolinite, talc, 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.

As the dispersant (C) used in the present invention, a phosphorus compound and ammonia or a lower amine compound are used. Preferred phosphorus compounds include phosphoric acid, phosphorous acid, phonephonic acid, and partial ester compounds thereof; specifically, phosphoric acid, phosphorous acid, phosphoric acid monoethyl ester,
Examples include methyl ethyl phosphate, di-1-thyl phosphoric acid ester, methylphosphonic acid, phenylphosphonic acid, and monomethyl ester. 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 R1R2R
3R4N or R+R+R3R4N+X- (in the formula R1 to R
1 is a hydrogen group or a lower alkyl group of C5 or less, and X- is a counter ion such as a hydroxyl group or a halogen). Mention may be made of triethylamine, tetraethylammonium hydroxide, 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. If the number of carbon atoms in the alkyl group is 1 or more, problems such as coloring of the polymer during polymerization occur, which is not preferable. The phosphorus compound and ammonia or lower amine compound may be added separately or simultaneously at the time of slurry preparation; however, it is also 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 5/1 to 115, more preferably 2/1 to 115.
It is 1/4, most preferably 1/1 to 1/3.

If the molar ratio is outside the above range, the dispersion effect will be insufficient,
There is a tendency for particles to reagglomerate in the polymer. The amount of the dispersant added is preferably 1/1 to 0.0001/1, more preferably 0.0001/1, as the total amount of the phosphorus compound and ammonia or lower amine compound, relative to the inorganic fine particles used.
5/1 to 0.001/1, most preferably 0.3/1 to
It is 0.01/1. The amount of dispersant added is 1/1 by weight
If the amount is more than 0.0001/2, the polymerization rate tends to decrease and the amount of diethylene glycol by-produced increases.
When it is less than 1, the effect of improving dispersibility is small.

Examples of the slurry solvent used in the present invention include water, alconyls 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 and average particle size of the inert inorganic fine particles (A) used and the type and size of the particles (B) used together.

That is, a stirring device equipped with one or more stirring blades such as propeller blades, paddle-shaped tools, turbine blades, and cross-shaped discs is used, and the stirring speed is preferably 100 to 10°ooorpm, more preferably 5 minutes to 10 hours, and more preferably 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 the other method, and then use the slurry as it is, or filter the slurry again or use a super decanter to remove coarse particles remaining in the slurry. is added to the reaction system for producing polyester.

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 amount of inert fine particles (A>) added is 5.0% by weight based on the polymer obtained after the polymerization reaction.
It is preferable to add the following amount.

Furthermore, the polyester referred to in the present invention may be any polyester that can be formed into fibers, such as polyethylene terephthalate, poly-1,4-cyclohexylene dimethylene terephthalate, polytetramethylene Terephthalate, polyethylene 2.6-naphthalene dicarboxylate, polyethylene-α, β-bis(2-chlorophenoxy)ethane-4
, 4'-dicarboxylate, etc., but it is a polyester in which part of the non-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 a part of the ethylene glycol component is replaced with another diol component.

Furthermore, the polyester may be copolymerized or mixed with various additives, such as a dye-facilitating agent, a fuel agent, an antistatic agent, and a hydrophilic agent, as required.

In this way, by spinning the obtained inert inorganic fine particle-containing polyester at an ultra-high speed of 5000 m/min or more,
The problems of ultra-high speed spinning in conventional methods are solved.

Further, 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, an 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 solidified in a cooling cylinder 3, and then oiled in an oil supply device 4, where it is 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' and is then wound onto a winder 116.

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 first GD and the second 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.

[Effects of the invention] When a specific inorganic fine particle-containing slurry employing the inorganic fine particle dispersant and dispersion method described in the claims of the present invention is used, the amount of aggregated particles present in the polymer is extremely small and uniform. Since a dispersed polyester can be obtained, the following effects can be exhibited by melt-spinning such polyvarnish tochill 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 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.

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

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

In addition. The physical properties in Examples were measured as follows.

A, average particle size Measured using the BET method.

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

C. Agglomerated coarse particles in polymer A small amount of polymer is sandwiched between two cover glasses 280'
After melt-pressing at C 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.

Regarding the dispersibility of particles, the average present in 1 mm2 -
Agglomerated coarse particles having a size exceeding 4 times the diameter of the next particle were observed and judged as follows.

Grade 1: The number of aggregated coarse particles having a size more than four times the average primary particle diameter is less than 10 pieces/mm2.

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

Grade 3: Agglomerated coarse particles with a size more than 4 times the average primary particle diameter are present at 30 or more/mm2 but less than 50/mm2.

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

D. Intrinsic viscosity measured at 25°C using O-chlorophenol as a solvent.

Example 1 12 parts of titanium dioxide with an average primary particle size of 0.37μ, 0.4 parts of phosphoric acid, 0.4 parts of triethylamine, 100 parts of dilene glycol, and 15 glass beads with a particle size of 80μ.
0 part was charged into a stirring device equipped with a turbine blade, and 200 parts
The mixture was stirred at Orpm for 3 hours. After stirring, the glass beads were separated and removed using a 400-mesh wire mesh to obtain an ethylene glycol slurry of titanium dioxide. The average diameter of titanium dioxide in the slurry was 0.4μ. On the other hand, 100 parts of dimethyl terephthalate, 65 parts of ethylene glycol, and 0.04 parts of manganese acetate were charged at 140-240'C.
The transesterification reaction was carried out. Next, 0.03 parts of antimony trioxide and 3 parts of the titanium dioxide ethylene glycol slurry described above were added, and a polymerization reaction was carried out under high vacuum at 250 to 290'C to obtain a polymer having an intrinsic viscosity of 0.65.

When the dispersion state of particles in the polymer was observed, the number of agglomerated coarse particles was 3/mm2, indicating a good dispersion state. jq
The resulting polymer was melt-spun at a spinning temperature of 305° C., a discharge rate of 11.3 Q/min per single hole of the nozzle, and a spinning speed of 8200 m/min after passing through a sand layer with a particle size of 120 mesh in a pack. The results are shown in Table 1. As is clear from Table 1, according to the method of the present invention, the occurrence of yarn breakage during spinning and fuzz during warping is small, and as a result of observing the yarn obtained in this example with a transmitted light microscope, it was found that An ultra-high speed spun yarn with no voids or cracks was obtained.

In Comparative Example, a slurry was prepared in the same manner as in Example 1 except that 0.4 part of phosphoric acid and 0.4 part of trimethylamine were not added in the method for preparing an ethylene glycol slurry of titanium oxide. The average diameter of titanium dioxide in the obtained slurry was 0.5μ
Met.

Using the obtained slurry, polyethylene terephthalate was produced in exactly the same manner as in Example 1 to obtain a polymer having an intrinsic viscosity of 0.65.

When the state of dispersion of the particles in the polymer was observed, the number of aggregated coarse particles was 10 pieces/mm2, and the state of dispersion was not satisfactory.

The obtained polymer was melt-spun at a spinning temperature of 305° C., a discharge rate of 1.30/min per single spinneret hole, and a spinning speed of 8,200 m/min after passing through a sand layer with a particle size of 120 mesh in a pack. The results are shown in Table 1.

As is clear from Table 1, the pack life during spinning was less than half that of the present invention, and on the other hand, the number of yarn breakages occurred nearly twice that of the present invention.

In the comparative example, a slurry was prepared in the same manner as in Example 1, except that 0.4 parts of phosphoric acid, 0.4 parts of i~lymethylamine, and glass beads with a particle size of 80μ were not added in the method for preparing an ethylene glycol slurry of titanium oxide. It was adjusted. The average diameter of titanium dioxide in the obtained slurry was 0.7μ.

Using the obtained slurry, polyethylene terephthalate was produced in exactly the same manner as in Example 1 to obtain a polymer having an intrinsic viscosity of 0.65.

When the state of dispersion of particles in the polymer was observed, the number of aggregated coarse particles was 35/mm2, indicating that the state of dispersion was poor. The obtained polymer was melt-spun at a spinning temperature of 305° C., a discharge rate of 1.3 Q/min per 10-gold single hole, and a spinning speed of 8200 m/min after passing through a sand layer with a particle size of 120 mesh in a pack. The results are shown in Table 1.

As is clear from Table 1, the pack life during spinning was short and yarn breakage occurred frequently. In addition, many voids and crack-like defects were present in the obtained system.

Example 2 A slurry was prepared in the same manner as in Example 1, except that the average primary particle diameter of titanium dioxide, the 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 temperature of 295°C10
Gold discharge per single hole 12.7q/min, particle size 100 in the pack
After passing through the sand layer of the mesh, it was melt-spun at a spinning speed of 7,800 m/min. Table 2 shows the dispersion state in the polymer, the number of times yarn breakage occurs during spinning, and the degree of increase in pack internal pressure after spinning.

In Table 2, Experiment No. 1 is inert inorganic fine particles (Δ)
Since the average primary particle size of the fiber is large, the internal pressure of the pack during spinning is large and the number of occurrences of yarn breakage is high.

In addition, in Experiment No. 2, since the particle size of the particles (B) was large, the dispersion state in the polymer was poor, the pack internal pressure increased greatly during spinning, and the number of yarn breakages was high. Experiment No. 3
Experiment No. 4.5 did not use a dispersant, and Experiment No. 4.5 used a dispersant other than the present invention. For this reason, the state of dispersion in the polymer was poor, and the pack internal pressure after spinning was medium to large, making it unsuitable for practical use.

Experiment N is an example of the inorganic particles (A>) of the present invention.

, 6 had a small increase in pack internal pressure during spinning, and the number of yarn breakages was also small, so that spinning could be carried out 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 22 Punk housing 3: Cooling cylinder 4: Oil supply device 5: 1st GD 5': 2nd GD 6: Winding machine

Claims (1)

[Scope of Claims] When producing polyester fibers, inert inorganic fine particles (A) having an average primary particle size of 2 μm or less are mixed in a solvent with an average primary particle size of 10 to 400 μm of the average primary particle size of the inorganic fine particles (A).
Particles (B) having a diameter of 0 times the diameter and an average particle diameter of 0.5 mm or less, a phosphorus compound and ammonia or a lower amine compound as a dispersant (C) are stirred with a solvent, and then particles (B) Inorganic fine particles (A) obtained by separating
1. A method for producing polyester fibers, which comprises melt-spinning a polyester obtained by adding a slurry of the above to a polyester production reaction system at a spinning speed of 5000 m/min or more.