JPH0197209A - Polyester fiber - Google Patents

Abstract

PURPOSE:To provide the title fiber having structure difference in the cross-sectional direction of fiber, exhibiting specific physical properties, developing excellent crimp when used as a pile yarn of flocked cloth, capable of realizing both excellent designability and feeling and having excellent dyeability, etc. CONSTITUTION:The objective fiber has a structure difference in the cross-sectional direction of the fiber, a peak temperature Tmax of tandelta-temperature curve of <=120 deg.C, a breaking elongation E of 30-70% and a density D of >=1.36g/cm<3> and can develop 1-10 crimps per 1cm by the heat-treatment at 180 deg.C under no-load. The fiber is preferably produced by passing a polyester fiber produced by conventional melt-spinning process through a heat-reserving zone extending 100-250mm under a spinneret, asymmetrically cooling the fiber with chilled air blasted at a flow rate of 100-150m/min within 450mm from the spinneret and taking up at a high take-up speed of >=5,500m/min.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to crimped polyester fibers. More specifically, the present invention relates to crimped polyester fibers that have excellent dyeability and can provide excellent design and texture when used in the pile portion of a raised blanket.

[Conventional technology] Polyester fibers are not only widely used as textiles for clothing and clothing due to their excellent mechanical properties, dimensional stability, and easy care properties, but also in recent years, their excellent durability Therefore, it is widely used in interior applications such as car seats. In recent years, raised blankets using polyester fibers in the pile have been preferred for this interior use, but when ordinary polyester fibers are used for raised blankets, the texture is hard and lacks a sense of luxury, and dark colors are difficult to express. There are problems such as harshness.

In order to solve this problem, one idea is to slightly crimp the polyester fibers used in the pile portion of the raised fabric to soften its texture. Conventionally known polyester crimped yarns include false-twisted yarns and composite crimped yarns made by laminating different polymers side-by-side; however, when these known fibers are used as pile yarns, crimps can be developed under no load. Because of this, the crimp comes out too strongly, creating a felt-like texture, which is the opposite of what was intended, and is ineffective.

In addition, Japanese Patent Publication No. 31-6768 describes latent crimped yarn obtained by high-speed spinning, but even if polyester fibers that have simply been spun at high speed are used, sufficient crimping will not occur and there will be no effect. .

Further, JP-A-56-159313 discloses fibers that are subjected to non-uniform cooling at a spinning speed of 3.700 m/min and then developed crimps using a heated fluid nozzle. The yarn is obtained at a low spinning speed, has a high elongation, and has a problem of poor knitting and weaving properties because it is crimped.

As described above, conventionally, crimpable polyester fibers suitable for pile yarns of raised fabrics have not been obtained.

In other words, heat is applied to the pile part in a no-load (free) state, and crimp occurs at that time, so it is designed with the aim of producing crimp under the constraint of tissues such as woven and knitted fabrics, as in the past. For fibers that have been crimped or for which crimps have already become apparent during knitting or weaving, the desired effect cannot be obtained when developed into pile yarn.

[Problems to be Solved by the Invention] The purpose of the present invention is to solve the drawbacks of the conventional technology, and to create a fabric that exhibits good crimp when used as a pile yarn for a raised fabric, and achieves a good texture of the fabric. An object of the present invention is to provide a polyester fiber that can be dyed easily and has good dyeability.

[Means for Solving the Problems] The object of the present invention described above is to have a fiber having a structural difference in the cross-sectional direction, and to have a tan δ retention temperature oil temperature curve temperature (Tmax) of 12
0°C or less, elongation at break (E) of 30 to 70%, density (D)
is 1.369/cm or more, and this can be achieved by a polyester fiber characterized by developing 1 to 10 crimps/cm after heat treatment at 180° C. under no load.

The polyester in the present invention is a polyester whose main repeating unit is ethylene terephthalate, but
A polyester copolymerized with a small amount of a third component may also be used.

The polyester fiber of the present invention needs to have a peak temperature Tmax of tan δ-temperature curve of 120° C. or less. T
When the max exceeds 120°C, the dyeability is insufficient and it is difficult to express deep colors. Tmax is generally a parameter corresponding to the structure of the amorphous portion of the fiber, and indicates that the higher l'-max, for example, the higher the degree of amorphous orientation, the more solid the structure of the amorphous portion becomes.

The Tmax of general polyester fibers is approximately 140°C, and the Tmax of polyester fibers copolymerized with a third component to improve dyeability is around 130°C. On the other hand, the 1max of the polyester fiber of the present invention needs to be kept at a significantly low temperature, and good dyeability can only be achieved when the 1max is set to 120° C. or lower, and even deep colors can be easily expressed.

Roughly, the elongation at break (E) of the polyester fiber of the present invention is 3
It needs to be between 0 and 70%.

If the elongation (E) exceeds 70%, the fibers will be elongated during processing such as knitting and weaving, causing shear defects and lowering the quality of the product. In addition, if the elongation is less than 30%, fuzz will occur during processing due to the low elongation, and knitting performance will deteriorate due to fuzz mixed in the raw yarn itself, resulting in frequent yarn breakage during knitting. . From this point of view, a more preferable range of elongation is 35 to 5.
It is 0%.

Furthermore, the density of the polyester fiber of the present invention (D> is 1.36
It needs to be 9/cTj or more. Density is 1.36g/
When it is less than cff1, light resistance deteriorates. This is because density is generally a parameter that indicates the crystallinity of the fiber, and the higher the density, the more stable the internal structure, but if the density is less than 1.369/cm', the fiber does not have sufficient crystallinity. It is thought that this causes a decrease in light resistance.

Further, the polyester fiber of the present invention needs to have 1 to 10 crimps/cm after being heat-treated at 180° C. under no load. If the crimp depth is less than r&1, the softening effect aimed at by the present invention cannot be obtained, and conversely, if the number of crimp threads exceeds 10, a felt-like texture will result, which is not desirable. From this point of view, the more preferable number of crimp threads is 2 to 5 threads/α.
It is.

The cross-sectional shape of the polyester fiber of the present invention is not particularly limited, but non-circular cross-sections such as triangular, multilobal, π, and H shapes are preferred because good crimp can be obtained.

Further, the denier of the polyester fiber of the present invention is not particularly limited, but the effects of the present invention are particularly exhibited when the total denier is 50 to 150 denier and the single yarn denier is 1 to 4 denier.

Roughly, the polyester fiber of the present invention is used for ordinary clothing and interior applications, but is particularly suitable for applications where crimp development treatment (heat treatment) is performed under no load (unrestrained) conditions.
For example, the effect is particularly remarkable when used as pile yarn for raised fabrics such as tricot napping, double raschel ball, and moquette.

Next, preferred examples of the method for obtaining the polyester fiber of the present invention will be described below.

The polyester fiber of the present invention is produced by melt-spinning polyester yarn according to a conventional method, passing it through a heat-retaining zone of 100 to 250# below the spindle, and then blowing it at a wind speed of 100 to 1
Asymmetric cooling with a cooling wind speed of 50 m/min, take-up speed 55
14 by spinning at a high speed of 00 m/min or more.

For example, l'-
max exceeds 120°C, and the polyester fiber of the present invention cannot be obtained. In addition, as a means of lowering the above-mentioned 7max, there is a method of lowering the draw ratio during fiber production to lower the degree of amorphous orientation to lower Tmax. Occasionally, tree defects occur.

In order to obtain the polyester fiber of the present invention in this way,
Asymmetric cooling with high speed spinning is the most preferred method.

[Example] Hereinafter, the effects of the present invention will be explained in more detail with reference to Examples. Note that the physical properties in the examples were measured as follows.

A, Tmax Using Pybron DDV-II type manufactured by Toyo Baldwin Co., Ltd., frequency of 110 Hz, temperature increase rate of 30°C/min, measurement temperature: maximum temperature to 190°C in air (temperature: 23±2°C, 150°C)
5% RH), find a temperature curve with ↑anδ, and set the temperature corresponding to the peak of tanδ as '1'-max.

B. Elongation at break Using a Tensilon tensile tester manufactured by Toyo Baldwin Co., Ltd., the S-8 curve was determined at a test length of 200 m and a tensile speed of 100 m/min, and the elongation corresponding to the maximum stress was determined as the elongation at break.

C1 Density The density of the fibers is determined by the density gradient tube method using n-hebutane as the light liquid and carbon tetrachloride as the heavy liquid.

D. Number of crimped threads Heat-treat the sample at 180°C for 5 minutes under no-load (free) conditions to develop crimps, then divide the sample into single yarns and leave them on a mount. (No load) Count the number of peaks and valleys that exist within 1 cm, and take the total as 1/2. This measurement is repeated five times and the average value is taken as the number of crimp ridges.

E, Light resistance The sample was knitted into a 27 gauge tube, and after scouring, dye Re5ol was applied.
The samples were stained with in Blue FBL (manufactured by Daiichi Kasei Co., Ltd.) and irradiated at 83° C. for 1300 hours using a fade meter (model FA-2) manufactured by Suga Test Instruments Co., Ltd. to determine the gray scale. A level of grade 3 or higher on the gray scale was defined as a pass (○).

Example 1 7 using polyethylene terephthalate by the method shown below
A 5 denier-24 filament fiber was obtained.

(Manufacturing method 1) No. 1 to N093 in Table 2 Spinning temperature 295
After the yarn discharged from the Y-shaped nozzle at ℃ passes through a temperature zone of 160# below the nozzle, cooling air at a temperature of 20℃ is asymmetrically applied from one side from a chimney with a blowing length of 100 m at the wind speed shown in Table 1. After applying it to the yarn, it was taken off at the take-off speed shown in Table 1 to obtain a polyester fiber of 75 denier and 24 filaments.

Table 1 (Manufacturing method 2) The yarn discharged from a Y-shaped nozzle at a spinning temperature of 290°C was
After passing through the heat insulation zone of 130 feet under the base, the blowing length is 200 mm.
Cooling air was blown asymmetrically from one side at a wind speed of 100 m/min and a temperature of 20°C from the # chimney, and the take-up speed was 13.
00 m/min, and immediately changed the stretching ratio under the conditions of stretching temperature 85 ° C. 1 heat treatment temperature 140 ° C.
-6. Elongation 36.9%, 89.4%, 25.6
% of each polyester fiber (75 denier-24 filament) was obtained.

(Manufacturing method 3) The yarn discharged from the round-hole spinneret at a spinning temperature of 290°C is cooled by a conventional method, and taken off at a take-up speed of 3000 m/min.
I got Y. This POY is twisted with 320 twists using the friction method.
Intro-false twisting was performed at 0 T/m and a heater temperature of 215° C. to obtain a false-twisted yarn of 75 denier and 24 filaments.

(Table 2 No. 7 > (Production method 4) At a spinning temperature of 290°C, the intrinsic viscosity was 0.83 and the intrinsic viscosity was 0.
．． 50 polyethylene terephthalate were separately melted;
The mixture was compounded side by side at a compounding ratio of 1:1, discharged from a nozzle, cooled according to a conventional method, and then taken off at a taking speed of 1000 m/min.

The obtained undrawn yarn was stretched at a temperature of 80°C and a heat treatment temperature of 135°C.
C. to obtain a spiral crimped yarn of 75 denier and 24 filaments.

(No. 8 in Table 2) (Hereafter, blank space) Table 2 shows the Tmax, elongation, density, and number of crimps of the fibers obtained in Manufacturing Methods 1 to 4.

Furthermore, a raised blanket (pole tricot) was prepared using the fibers of No. 1 to Na8 as pile yarns according to a conventional method.

The texture, dyeability, light resistance, and knitting properties of this raised fabric were evaluated and shown in Table 2.

As is clear from Table 2, No. obtained by simple high-speed spinning,
No. 1 had few crimps and a good texture could not be obtained. In addition, in No. 3, where the spinning speed was low, the elongation was high and the fabric had shear defects and knitting properties were poor, and the density was low, so the light resistance deteriorated significantly. In addition, No. 4.5.6 obtained by the normal stretching method, the stretching ratio was lowered.
No. 5 had too high elongation and poor knitting properties, and No. 4 with increased magnification had TmaX exceeding 120° C. and dyeability deteriorated.

In N096, which had a further increased magnification, not only the dyeing property deteriorated but also the elongation decreased, the fluff was mixed in and the VA was heavy, and the knitting property was also deteriorated. In addition, in the case of ordinary false twisting or side-by-side composite yarn with Nα7.8, Hmax exceeded 120° C. and dyeability was not only poor, but also the number of crimps was too large and the fabric texture became felt-like, which was not good. knitting properties, texture, dyeability,
No. 2 that satisfies both durability and satisfies the scope of the present invention
It was only.

[Effects of the Invention] The polyester fiber of the present invention is an unprecedented polyester fiber that has excellent dyeability, good knitting properties, light resistance, and good crimpability without being dull.

In addition, when the polyester fiber of the present invention is used in applications where crimp development treatment is performed under no-load conditions, such as the pile part of a pile fabric, the crimps will not be too strong or too weak, and will have good wind resistance. A wavy blanket is obtained.

Claims (1)

[Claims] Has structural differences in the fiber cross-sectional direction, peak temperature (Tmax) of tan δ ~ temperature curve is 120 ° C or less, elongation at break (E)
is 30 to 70%, the density (D) is 1.36 g/cm^3 or more, and after heat treatment at 180°C under no load, crimps with a number of crimp ridges of 1 to 10 ridges/cm are developed. polyester fiber.