JPH11269721A - Polyester thick-and-thin multifilament - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject filaments suitable for the use of clothes such as thawbs and turbans, and excellent in an opaque property, an ultraviolet light screening property, etc. by producing sheath-and-core type conjugate filaments containing an inorganic metal oxide in a high concentration in the core component on specified conditions. SOLUTION: The polyester thick-and-thin filaments are obtained by melt- spinning multifilaments comprising sheath-and-core type conjugate filaments containing 5-20 wt.% of an inorganic metal oxide in the core component, then firstly and directly, without taking up the spun multifilaments, drawing the spun multifilaments with pairs of heated godet-rolls to achieve an unevenness (U%) of the filament fineness in the range of >=8%, and further secondly drawing the firstly drawn multifilaments with pairs of heated godet-rolls and unheated godet-rolls to achieve an unevenness (U%) of the filament fineness in the range of 2-8%. The obtained polyester thick-and-thin multifilaments (the extremum of shrinkage stress on dry heating is observed at a temperature in the range of 80-120 deg.C) have an excellent property for developing clear patterns on a fluorescent whitening treatment, and further excellent drapeability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester thick multifilament, a knitted fabric and a process for producing the same, which are excellent in patterning and drapeability in white (brightening) dyeing in addition to sheer-proofing and ultraviolet shielding properties. In particular, in particular, knitted and woven fabrics suitable for use in clothing such as tows and turbans in regions such as the Middle East, polyester fine multifilaments suitable for the production of such woven fabrics, and an efficient method for producing the same It is about.

[0002]

2. Description of the Related Art In Arab countries, folk costumes such as tows and turbans have been worn by many people since ancient times. In recent years, in these countries as well, there has been a strong demand for high-performance and high-quality costumes. For example, there is a growing demand for functions such as anti-transparency, in which the line of underwear is not visible without lining, and ultraviolet shielding, which shields strong sunlight and ultraviolet rays. Although most of these costumes are used in white, those that are dyed white but are not plain but patterned in a Kasuri style pattern are preferred. Further, the texture of the fabric is not a bulky dry tone, but a "mellow tone" draped texture that combines flexibility and comfortable smoothness is preferred.

[0003] However, at present, fabrics satisfying both of these functions and a high-grade feel and polyester multifilaments for providing the fabric have not yet been obtained. Conventionally, it has been known to use a multifilament containing a high concentration of inorganic metal oxide fine particles as a polyester multifilament for the purpose of improving functions such as an anti-sheer thread for preventing the clothing from being transparent or an ultraviolet ray shielding property. ing.

In order to improve the abrasion of the guides when these multifilaments are knitted,
Multifilaments in which the constituent filaments are sheath-core type composite filaments and inorganic metal oxide fine particles are contained only in the core component at a high concentration are disclosed in, for example, JP-A-55-15833.
No. 1 and Japanese Patent No. 2678110. However, although the fabric obtained from this known sheath-core type composite multifilament has excellent anti-reflective properties and ultraviolet ray shielding properties, it does not have a high-grade feeling such as drape even when used alone. For this reason, at present, this kind of sheath-core type composite multifilament is used by being composited with other fibers.

For the purpose of giving a high-grade sense of a marbling pattern to a fabric, so-called thick and thin (thin and thin) multifilaments having a thickness in the length direction of the filament are disclosed in, for example, Japanese Patent Publication No. 6-94609, and 57-117
610 and JP-A-57-199813. Thick and thin multifilaments have a thicker dye-absorbing property in the unstretched part of the thick part existing in the length direction of the filament than that of the stretched part in the thin part. It is said that a so-called "pattern" is expressed, which gives a sense of quality. This pattern
Depending on the length of the thick portion of each filament and the state of assembly of the thick portions when the filaments are assembled into a multifilament, different patterns are formed. For example, when the thick portion is short in the single-filament filament disclosed in Japanese Patent Publication No. 6-94609 and the thick portion is randomly dispersed even in the multifilament, it is called a filament dispersion type. The resulting fabric has a solid color with a pattern difficult to see (for example, Japanese Patent Publication No. 6-94609). On the other hand, for example, JP-A-57-117610,
In a thick and thick yarn disclosed in Japanese Patent Application Laid-Open No. 57-199813, when a thick portion is long in a filament, and dispersion is uneven in a multifilament and the thick portion is gathered, a concentrated type is used. And the pattern of the cloth is in the pattern of Kasuri.

In the case of using chic and thin yarn fabrics dyed with chromatic colors, a high-class feeling can be obtained even in the former solid color tone. It is not possible to express a high-class pattern in a Kasuri style on the fabric. Japanese Patent Application Laid-Open No. 59-94617 proposes a thin polyester multifilament composed of filaments containing inorganic metal oxide fine particles at a high concentration.
JP-A-62-85021, JP-A-6-81212
And Japanese Patent No. 2,589,226. However, as is well known, it is difficult to obtain a pattern having a long thick portion with a filament containing inorganic metal oxide fine particles at a high concentration. For example, Japanese Patent No. 2,589,226 discloses that a filament containing inorganic metal oxide fine particles in a high concentration is drawn to obtain a thick polyester multifilament. However, according to the disclosure of this known patent, since the thick part is extremely short and is too uniformly dispersed among the multifilaments, there is a problem that the pattern is difficult to be seen by white dyeing, and the pattern becomes plain. As described above, the texture of the cloth made of the thick polyester multifilament obtained by stretching the filament containing the inorganic metal oxide fine particles at a high concentration is a bulky so-called dry touch, and lacks the drape property.

[0007] Japanese Patent Application Laid-Open No. 61-108735 discloses a spinning draft (melt spinning speed / spinneret) composed of a sheath-core type composite filament containing a high concentration of inorganic metal oxide fine particles in a core component. Unstretched yarn having unevenness in the fiber axis direction by a special spinning method such as making the linear velocity (in-hole linear velocity) at least twice as large as during normal spinning, and bringing the particles of the cooling liquid into contact with the yarn under the spinneret. Is manufactured and then subjected to false twisting to utilize the unevenness of the thickness of the undrawn yarn of the filament to provide a twisted yarn having an appearance and texture similar to cotton or hemp having a single yarn break or unevenness in thickness. And
Thick-and-thin filaments, which consist of filaments with undrawn humps that are irregularly formed during drawing that enable a unique kasuri-like pattern of chic and thin yarn and a knitted fabric with a drape-like texture Absent.

Hitherto, polyester multifilaments have been produced exclusively by a two-step process of low-speed spinning and drawing. Conventionally, polyester multifilaments have been produced through a two-step process of low-speed spinning and drawing. This two-step process is economically disadvantageous because the winding form is a pirn shape, the winding weight is at most 2 to 3 kg, and the production requires labor. Recent Yen appreciation
In the era of “price destruction” and these high-quality materials, high cost competitiveness has been required.

In order to reduce costs, a direct spin drawing method in which a conventional two-step process is continuous is generally known, and the production of general-purpose yarn has already been industrialized. What is demanded from the economics of post-processing is to make the yarn package larger (increase the winding weight). This is because the smaller the winding weight, the more the creel, that is, the number of yarn preparations, and the more the manpower is required, which is uneconomical.

[0010] Therefore, even if it is a fiber material for a high-quality garment such as a polyester thick and thin multifilament in recent years, a high cost competitiveness is required, and like the general-purpose polyester filament, the direct spinning and winding method is used. It is required that the production and large packaging (increase in winding weight) increase the economic efficiency of yarn production and post-processing.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of a sheath-core type composite filament containing a high concentration of inorganic metal oxide fine particles in the core component, and to improve the sheer-proofing property and ultraviolet shielding property. In addition, another object of the present invention is to provide a polyester thick polyester multifilament and a knitted fabric capable of providing a fabric excellent in patterning property and drape property by white dyeing.

Another object of the present invention is to provide a method for producing a polyester thin multifilament by an improved direct spin drawing method, which can produce a polyester thick multifilament in a large package.

[0013]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a sheath-core type composite filament containing a high concentration of inorganic metal oxide fine particles in a core component. Polyester thin polyester multifilaments which are constructed and have excellent patterning and draping properties in white dyeing in addition to sheer-proofing and UV-shielding properties and knitted fabrics can be obtained by a unique direct spinning and drawing method. The object of the invention has been solved.

An object of the present invention is a polyester thin multifilament composed of a sheath-core composite filament containing a core component containing 5 to 20% by weight of inorganic oxide fine particles, wherein the multifilament has a dry heat shrinkage stress. Is 80 ° C. to 120 ° C. and the fineness variation value U% is 2% to 8
%, Which is achieved by a polyester thick multifilament which is characterized in that

[0015] The present invention provides a polyester which is excellent in patterning by white dyeing and drapability in addition to sheer-proofing property and ultraviolet ray shielding property by partially or entirely using the polyester thin multifilament specified above. It has enabled the production of fiber knitted fabrics. According to the present invention, the polyester thick and thin multifilament is obtained by melt-spinning a multifilament composed of a sheath-core composite filament having a core component containing 5 to 20% by weight of inorganic oxide fine particles.
In a direct spin drawing method in which an undrawn yarn is continuously drawn without being wound once, a multifilament drawing region is set to 2
The first stage is stretched between the first heated godet roll and the second heated godet roll, and the fineness variation U% of the multifilament is set to 8% or more, and then the second stage is heated with the second heated godet roll and not heated. It is stretched between third godet rolls, and the fineness variation value U% of the multifilament is 2% to
It can be manufactured by a method characterized by being 8%.

In the following, embodiments of the polyester thick polyester multifilament, the knitted fabric thereof and the direct spin drawing method of the present invention will be described in detail. The sheath-core type composite filament constituting the polyester thick multifilament of the present invention is required that the core component contains 5 to 20% by weight of inorganic oxide fine particles.

The sheath-core type composite filament is a sheath-core type filament composed of a sheath component and a core component and obtained by a known composite spinning method. The core component wrapped in the sheath component may be concentric with the sheath component or may be eccentric,
Generally, concentric ones are used. The composition of the sheath component and the core component may be the same polyester, or a copolymer polyester may be used for either one.

The polyester used for the sheath component and the core component contains 85 mol% or more of a polyethylene terephthalate unit. As the copolymer component, for example,
Dicarboxylic acids such as isophthalic acid, adipic acid, sebacic acid, and naphthalene carboxylic acid, diethylene glycol,
Glycols such as triethylene glycol and butylene glycol, and 5-natrium sulfoisophthalic acid can be exemplified. These polyesters may contain additional components such as heat and light stabilizers and antistatic agents as long as the object of the present invention is not impaired.

The weight ratio of the sheath component to the core component is 1: 4 to 4: 1.
Is preferable. When the ratio of the sheath component falls below 1: 4,
The core component is exposed on the surface of the filament during spinning, making it difficult to obtain a stable sheath-core shape. Preferred sheath-core ratio is 1 to 2
Two to one. More preferably, the ratio is one to one. The sheath-core type composite filament of the present invention needs to contain 5 to 20% by weight of inorganic oxide fine particles in the core component. The average content of the inorganic oxide fine particles contained in the sheath-core type composite filament of the present invention is preferably 3 to 15% by weight.
The higher the average content, the more excellent the anti-transparent property and the ultraviolet shielding property. However, as the content increases, the mechanical properties such as the strength of the sheath-core composite filament decrease.
The preferred average content is 3 to 10% by weight.

The inorganic oxide fine particles to be used in the present invention are fine particles having a sheer-proofing property and an ultraviolet shielding property.
For example, titanium oxide, zinc oxide, calcium carbonate, barium sulfate, talc, kaolin and the like can be exemplified. Most preferably, it is titanium oxide.
These inorganic oxide particles can be used alone or in combination of two or more. Generally, the average particle size of the inorganic oxide fine particles used is preferably about 1 micron or less. Coarse particles of about 2 microns or more undesirably lead to yarn breakage during spinning. More preferably, it is less than about 0.5 microns.

When the content of the inorganic oxide fine particles contained in the core component is less than 5% by weight, the light-shielding property and the ultraviolet ray shielding property are insufficient. If it exceeds 20% by weight, it becomes difficult to uniformly disperse the fine particles, and problems such as yarn breakage during spinning occur. The preferred content is 7% to 15% by weight. The polyester thin multifilament of the present invention needs to have an extreme temperature of the dry heat shrinkage stress of 90 ° C to 120 ° C.
By setting the extreme temperature in this range, it is possible to adjust the drapability of the fabric in the post-processing step, particularly in the relaxing step. That is, the fabric obtained by knitting multifilaments without twisting or after twisting is generally stretched without tension in hot water at 90 ° C. to 130 ° C., that is, most of the appearance of the texture is determined in a so-called relaxation process.

If the extreme temperature of the dry heat shrinkage stress is within the range of the present invention, it is possible to relax the once shrunk fabric by setting the relaxation temperature higher than the extreme temperature. Due to this relaxing action, it is possible to suppress the hardening of the texture and sufficiently express the drape property. Since the extreme temperature of the dry heat shrinkage stress of the known polyester thin multifilament is about 130 ° C. to 170 ° C., only the fabric shrinks in the relaxing step with hot water of 130 or less,
No relaxing action is obtained as in the present invention. When the extreme temperature of the dry heat shrinkage stress is less than 90 ° C., the relaxation is excessive in the relaxation step, and drape property cannot be exhibited. If the extreme temperature of the dry heat shrinkage stress exceeds 120 ° C., it is difficult to exhibit a drape-like texture even if the temperature is relaxed at 130 ° C. A preferred range of the extreme temperature of the dry heat shrinkage stress is 95 ° C to 120 ° C. Most preferably, it is 100 ° C to 115 ° C.

The polyester thin multifilament of the present invention is greatly characterized in that it has a thickness in the length direction. The thick and thin index is represented by a fineness variation value U% measured by an evening tester described later, and in the present invention, the fineness variation value U% needs to be 2% to 8%. By setting the fineness variation value U% within the range of the present invention, it becomes possible to express a Kasuri-like pattern. Fineness fluctuation value U% is 2%
If the amount is less than the above, the color becomes solid and the texture lacks drape. If the fineness variation value U% exceeds 8%, the frequency of the thick portion becomes excessive, and it becomes difficult to express a Kasuri-like pattern. In addition, the thick part becomes fragile at the time of alkali weight reduction processing or the like, resulting in defects such as "holes". A preferred fineness variation value U% is 2% to 5%.

The cross-sectional shape of the sheath-core type composite filament of the present invention is not limited to a circle, but may be a Y-shape, an oval-shape, or the like.
Irregular sections such as triangles, squares, and pentagons, and hollow sections can also be employed. The polyester thin multifilament of the present invention can be obtained by the combination of the extreme temperature of the dry heat shrinkage stress and the range of the fineness variation value of U% specified above. In addition to the properties, it is possible to obtain a knitted fabric excellent in patterning property by white dyeing and drape property expressed by "relaxing feeling".

The polyester thin multifilament of the present invention can be rationally prepared by the production method described below. A direct spin drawing method in which a multifilament composed of a sheath-core type composite filament having a core component containing inorganic oxide fine particles in an amount of 5 to 20% by weight is melt-spun and then undrawn yarn is continuously drawn without being wound once. , The stretching region of the multifilament is set to two stages, the first stage is stretched between the first heated godet roll and the second heated godet roll, and the fineness variation value U% of the multifilament is set to 8% or more, and then the second stage It is necessary to stretch the eyes between the heated second godet roll and the non-heated third godet roll so that the fineness variation value U% of the multifilament is 2% to 8%.

In the production method of the present invention, the above-described two-component polymer having a polyester as a sheath component and a core component is subjected to composite spinning.
For example, a sheath-core composite filament is spun using a method described in U.S. Pat. No. 3,381,074. That is, the respective polyesters forming the sheath component and the core component are melt-extruded by two extruders, and the two polymers are merged in a spinneret through a spin head and a pack made so that both polymers are fed without being merged. It is discharged from the hole as a sheath-core type composite filament. Then, after being cooled by a cooling air and applying a finishing agent, it is taken up by a first godet roll of a drawing machine rotating at a predetermined speed, and becomes an undrawn multifilament composed of a sheath-core composite filament.

In the present invention, it is necessary to perform multi-filament drawing in two steps in the direct spin drawing method.
In order to realize two-stage stretching, stretching equipment having first, second, and third godet rolls is required. In each godet roll, the first godet roll and the second godet roll are of a heating type, and the third godet roll is of a non-heating type.
The undrawn multifilament drawn by the heated first godet roll is heated on the heated first godet roll maintained at a predetermined temperature, and the first-stage drawing is performed at a peripheral speed ratio of the heated first godet roll and the heated second godet roll. Done.
Next, the second-stage stretching is performed at a peripheral speed ratio between the heated second godet roll and the non-heated third godet roll.

In the first stage of drawing, the undrawn yarn is moved between the first heated godet roll and the second heated godet roll,
It is necessary that the fineness variation value U% at this stage is stretched to 8% or more. Fineness fluctuation value U% is 8% in the first stage of stretching
If it is stretched to less than the fineness fluctuation value U% in the second stage of stretching
Is difficult to adjust to 2% to 8%. A preferred range of the first-stage stretching ratio is that the fineness variation value U% is 8% to 12%.
%.

The draw ratio for setting the fineness variation value U% in the above range depends on the speed of the first heated godet roll (same as the spinning speed), the fineness of the multifilament to be spun, the cross-sectional shape, and the like. Selected as appropriate. For example, if the spinning speed is 2000 m / min, the draw ratio is selected from 1.6 times to 2.2 times. Following the first-stage stretching, the second-stage stretching is performed between the heated second godet roll and the non-heated third godet roll, and the stretching is performed so that the fineness variation value U% of the multifilament becomes 2% to 8%. is necessary. The second stage stretching ratio is 1.01 times or more.
1.10 times is adopted. Preferably, 1.02 times or more
The ratio is 1.09 times, and most preferably 1.02 to 1.07 times. In the present invention, the temperature of the heated first godet roll is 6
0-90 ° C is preferred. More preferably, 60 ° C to 80 ° C
° C. The temperature of the heated second godet roll is 110 ° C ~
140 ° C. is preferred.

If the heated second godet roll is less than 110 ° C., the extremum temperature of the dry heat shrinkage stress of the obtained multifilament becomes less than 80 ° C., and the effect of the present invention cannot be obtained. The temperature of the second heated godet roll is 140
When the temperature exceeds ℃, the extreme temperature of the dry heat shrinkage stress becomes 120 ° C or more, and the effect of the present invention cannot be obtained. The preferable temperature range of the heated second godet roll is 120 to 140 ° C.

The third godet roll needs to be unheated. Here, the non-heating means that there is no heating device inside the godet roll. In actual production, the temperature is raised to about 30 ° C. to 70 ° C. depending on the atmosphere around the equipment, but within this range, the effects of the present invention are not hindered. Although not heated, the temperature of the third godet roll should not exceed 70 ° C. When the temperature exceeds 70 ° C., the extreme temperature of the dry heat shrinkage stress, which is an important requirement of the first invention of the present invention, exceeds 120 ° C., and the object of the invention is not achieved. The third godet roll is about 30 ° C to 60 ° C
It is preferable to keep it within the range.

In the present invention, the polyester thin multifilament that has exited from the unheated third godet roll is entangled by an interlacer and wound into a cheese-like package by a winder. The knitted fabric of the present invention,
It is a knitted fabric formed by knitting and weaving a part or all of polyester multifilaments.

The knitted fabric of the present invention may be used as a warp, a weft or a weft if the polyester thick multifilament is a woven fabric. Examples of woven fabrics include plain weave, satin, gazelle, twill, georgette, dobby georgette, piqué georgette, check georgette, georgette crepe such as chiffon georgette, lattice weave, and decin feather double weave crepe. Can be

Further, as the knitted material, smooth, velor, sheet of paper, pile, etc. are adopted, but the present invention is not limited to these. The knitted fabric of the present invention may be one using polyester thick and thin multifilaments alone or one obtained by mixing or interweaving with other fibers. The knitted fabric of the present invention may use a polyester thick multifilament in a non-twisted or twisted state. In the case of twisting, the number of twists is not particularly limited, but is usually 200 T / m to 30.
00T / m is adopted. In particular, in order to improve the see-through resistance, it is preferable to use a woven fabric whose cover factor (CF) represented by the following formula is designed to be as high as about 1000 to 3000.

CF = ([warp density / 2.54 cm] × √)
Warp total denier) + ([weft density / 2.54 cm] × √
Weft total denier)

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to embodiments, but the present invention is not limited to the embodiments.
In the present invention including Examples, the extreme temperature of the dry heat shrinkage stress and the fineness variation value U% are measured by the following methods. (1) Measurement of Extreme Temperature of Dry Heat Shrinkage Stress It is measured using a thermal stress measurement device (for example, product name KE-2 manufactured by Kanebo Engineering Co., Ltd.). The yarn (multifilament) is cut to a length of 20 cm, and the both ends are connected to form a loop, which is then loaded into a measuring machine. Initial load 0.05
g / d, the temperature was increased at a rate of 100 ° C./min, and the temperature change of the thermal stress was plotted on a chart. Read the peak value of the thermal stress curve. The temperature at which the value becomes the highest is the extreme temperature of the dry heat shrinkage stress. (2) Measurement of fineness variation value U% It was measured under the following conditions using USTER TESTER 3 (manufactured by Zellweger).

Measuring Sloot 3 Test time 5 minutes Tensional force 1.25% Pressure 2.5 bar Twist 1500S (3) Measurement of strength and elongation Measured according to JIS-L1015. (4) Ultraviolet ray shielding property The ultraviolet ray shielding property is measured by a spectrophotometer (UV-2 manufactured by Shimadzu Corporation).
200) The rate of transmission of ultraviolet light having a wavelength of 320 to 390 nm through the fabric was evaluated by transmittance of the measured ultraviolet light. The wavelength of 320 to 390 nm is a wavelength of sunlight that causes skin tanning. In the present invention, it was evaluated that the lower the UV transmittance, the better the UV shielding property.
Generally, when this value is 10% or less, it can be said that the ultraviolet shielding property is excellent. (5) Evaluation of texture The texture of the fabric was evaluated by three experienced engineers.も の indicates that the pattern is Kasuri-like and has a drape-like texture of “mellow tone”, ○ indicates that there is a little, and X indicates that even one of them is missing.

[0038]

EXAMPLES Examples 1 to 5 and Comparative Examples 1 to 3 Polyester thick multifilaments were prepared from the following polymers by direct spinning and drawing under various conditions. Sheath component: [η] = 0.65 polyethylene terephthalate (contains 0.5 wt% TiO ₂ ) Core component: [η] = 0.65 polyethylene terephthalate (contains 7.5 wt% TiO ₂ ) As a spinning machine, a known composite spinning machine and two continuous
Direct spinning and winding (spin draw take-up) is performed using a step godet roll type stretching machine. The mixing ratio of the sheath component and the core component was 1: 1. The average content of titanium oxide is 4% by weight. Spin at a spinning temperature of 295 ° C,
After cooling at a wind speed of 0.4 m / sec with a cooling air having a relative humidity of 5% to give an oil agent of 0.7% by weight, a sheath-core composite multifilament was obtained. The film was taken up by a first godet roll and continuously stretched in two stages without being wound up.

The first godet roll and the second godet roll of the stretching machine are both of a heating type, and the third godet roll is of a non-heating type. The stretching and winding conditions are 150 d /
Polyester thick multifilament of 72f was obtained.
The peripheral speed of the third godet roll is the second godet roll ×
This is the second-stage stretching ratio, and is 3800 to 4250 m here.
/ Min.

Stretching conditions First godet roll temperature 60 ° C. Peripheral speed 2000 m / min Number of laps 7.5 Second godet roll temperature 120 ° C. Peripheral speed 3800 m / min, ie, stretching ratio 1.90 times Number of wraps 6.5 Third godet roll temperature 50 ° C. Circumferential speed See Table 1. Number of laps 5.5 times Winding tension 0.15 g / d Winding weight 6 kg In the examples, the ratio of the second-stage stretching, that is, the ratio of the heated second godet roll to the non-heated third godet roll, is shown in Table 1. Was changed as shown in FIG. In each case, a large package having a good winding form could be obtained. Each of the obtained polyester thin multifilaments was subjected to 300 twists / m S twist as a warp. S for weft
Twisting and Z-twisting each 1800 times / m
In, a fabric of 68 wefts / in was prepared.

The cover factor of the fabric is 2364. The relaxation temperature before dyeing was 120 ° C.
The alkali weight loss rate was 15% by weight. Staining was performed using a fluorescent disperse dye and 5% owf, white staining at 130 ° C. for 60 minutes. Table 1 shows the evaluation results of the obtained woven fabric, the thick and thin patterns, the texture, and other factors. As is clear from Table 1, polyester fine multifilaments having a fineness variation value U% of 2% to 8% shown in Examples 1 to 5 have excellent sheer-proofing property, ultraviolet shielding property and Kasuri-like pattern. It is a fabric that excels in drapability of "mellow tone" in addition to the pattern.

Comparative Examples 1 and 2 had a fineness variation value U% exceeding 8%, which was large, and the thick portion was excessively reduced by alkali treatment, and had a "perforated" defect. In Comparative Example 3, the fineness variation value U% was less than 2%, which was small and lacked in Kasuri tone and drape.

[0043]

[Table 1]

Examples 6 to 9 and Comparative Examples 4 and 5
Except that the stretching ratio of the second stage, that is, the ratio of the heated second godet roll to the unheated third godet roll was fixed at 1.04 times, and the stretching ratio of the first stage was changed as shown in Table 2 Example 2 was repeated. Table 2 shows the results such as the texture of the obtained woven fabric.

The polyester multifilaments of Examples 6 to 9 in which the fineness variation value U% is 2% to 8% by adjusting the stretching ratio of the first step, have excellent anti-transparency and ultraviolet shielding properties. In addition to the kasuri-like pattern, a fabric with excellent "drip-like" drape property was obtained. Comparative Example 4 had a fineness fluctuation value U% exceeding 8% and was large, and the thickness of the thick portion was excessively reduced by the alkali treatment, and had a "hole" defect. In Comparative Example 5, the fineness variation value U% was less than 2%, which was small and lacked in Kasuri tone and drape.

[0046]

[Table 2]

Examples 10 to 12 and Comparative Examples 6 and 7 Example 2 was repeated under the same conditions as in Example 2 except that the temperature of the second heated godet roll was changed as shown in Table 3. Table 3 shows the results such as the texture of the obtained woven fabric. Third
As is clear from the table, in Examples 10 to 12 in which the extreme temperatures of the boiling water shrinkage and the dry heat shrinkage stress are in the range of the present invention, the polyester thin multifilament of the present invention has excellent anti-transparency and ultraviolet shielding. In addition to the pattern and the Kasuri-like pattern, a fabric with excellent "dwarf" drape was obtained.

In Comparative Example 5 in which the extreme temperature of the dry heat shrinkage stress was outside the present invention, the fabric was excessively relaxed in the relaxing step and was paper-like. In Comparative Example 6, the texture lacked drape.

[0049]

[Table 3]

[0050]

According to the present invention, there is provided a polyester-thin polyester multifilament and a knitted fabric capable of providing a fabric excellent in patterning and drapeability by white dyeing in addition to sheer-proofing property and ultraviolet shielding property. it can. In addition, it has become possible to produce polyester thick multifilaments by a direct spin drawing method which is economically advantageous in producing polyester thick multifilaments and a large package thereof.

Claims (4)

[Claims] 1. A polyester thick multifilament composed of a sheath-core composite filament containing a core component containing 5 to 20% by weight of inorganic oxide fine particles, and the extreme temperature of the dry heat shrinkage stress of the multifilament. Is 80 ° C to 120
C. and a fineness variation value U% of 2% to 8%. 2. The polyester thin multifilament according to claim 1, wherein the average content of the inorganic oxide fine particles contained in the sheath-core type composite filament is 3 to 15% by weight. 3. A multifilament consisting of a sheath-core composite filament containing 5 to 20% by weight of inorganic oxide fine particles as a core component is melt-spun and then directly drawn without winding the undrawn yarn. In the spinning drawing method, the drawing area of the multifilament is set to two steps, the first step is drawn between the first heated godet roll and the second heated godet roll, and the fineness variation value U% of the multifilament is set to 8% or more, Next, the second stage is stretched between the heated second godet roll and the non-heated third godet roll, and the fineness variation value U% of the multifilament is set to 2% to 8%, thereby producing a polyester thin multifilament. Method. 4. A polyester thin multifilament consisting of a sheath-core composite filament containing 5 to 20% by weight of inorganic oxide fine particles as a core component, wherein the multifilament has an extreme dry heat shrinkage temperature of 90%. ° C to 120 ° C
And a knitted and woven fabric comprising a polyester fine multifilament having a fineness variation value U% of 2% to 8% for a part or the whole thereof.