JPS60252732A - Production of spun yarn like polyester crimped processed yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for producing a spun yarn-like polyester crimped yarn having both excellent dispersion dyeing performance and crimping performance.

[Prior art]

One of the methods for producing spun yarn-like polyester crimped yarn is to mix two types of polyester filament undrawn yarns with different elongation moduli, and then to false-twist the yarn at the same time as stretching. After forming a two-layer twisted structure yarn in which the elongated modulus filament yarn is wound in one direction around the high elongated modulus filament yarn, the yarn is heat-set and then untwisted, thereby forming a core made of high elongated modulus filament and a low elongated modulus filament yarn. A method has been proposed in which an alternately wound structural thread is formed from a sheath made of elongated modulus filaments (Japanese Patent Application Laid-open No. 43432/1983).

However, this method has the following problems.

(1) In order to prepare two types of polyester undrawn yarn packages with different elongation moduli, it is necessary to separately spin polyester undrawn yarns with significantly different spinning speeds, and the package creel of the conventional simultaneous stretching and false twisting processing machine is required. must be converted into a large cloth.

(2) The two-layer twisted structure yarn, in which filament yarns with low elongation modulus and filament yarns with high elongation modulus formed in the false twisting heating region are wound in one direction, is heated by a heater and undergoes plastic deformation, but is not stretched at the same time. In the false twisting process, it is mainly the high elongation modulus filament yarn that is given crimp performance, and this high elongation modulus filament yarn forms the core in the two-layer twisted structure, so it is difficult to wind it. The crimp waves become so fine that excellent crimp performance, ie, high crimp rate and crimp recovery rate, cannot be obtained.

(3) Simultaneous drawing and pre-combustion processing is performed at a magnification suitable for filament yarns with high elongation modulus, but at this time, filament yarns with low elongation modulus undergo high temperature heat treatment without being sufficiently oriented. Compared to filament yarns, it now exhibits deep dyeing properties with 1 disperse dye,
As a result, shading occurs during dyeing.

[Purpose of the invention]

An object of the present invention is to provide a method for producing a spun yarn-like crimped polyester yarn that eliminates all the drawbacks of the conventional methods and has both excellent dispersion dyeing performance and crimping performance.

[Structure of the Invention] The present invention involves simultaneously spinning polyester (PET) containing ethylene terephthalate units and polyester (PBT) containing tetramethylene terephthalate units as independent yarns using the same melt spinning device. This is a method for producing a spun yarn-like crimped polyester yarn, which is characterized in that the spun, doubled, and mixed undrawn polyester yarns are subjected to simultaneous stretching and false twisting.

The present invention will be explained in detail below.

The reason why spun yarn-like crimped polyester yarn can be obtained in the present invention is as follows.

Generally, when undrawn yarn is twisted while being stretched, stress is generated in the yarn. However, when undrawn yarns consisting of filaments with different elongation moduli are simultaneously stretched and twisted, the stress balance between the filaments with low elongation modulus and the filaments with high elongation modulus is lost with respect to the stress generated in the yarns. . However, in this case, most of the low elongation modulus filaments are elongated more than the high elongation modulus filaments, and by winding around the latter high elongation modulus filaments, they become a single thread. Maintains stress balance.

As a result, even if the constituent filaments are in a mixed fiber state, by creating a difference in elongation modulus between the filaments, in the false twist firing region, a group of filaments with a high elongation modulus, a group of filaments with a low elongation modulus, and a group of filaments with a low elongation modulus of 71 lame 7 A double-layer twisted structure yarn is formed in which the groups of fibers are wound in one direction and some portions where the fibers are mixed with each other remain.

Furthermore, by heat-treating the two-layer twisted structure yarn with a heater to cause plastic deformation in the constituent filaments, fixing that state, and then untwisting the yarn, a core consisting of high elongation modulus filaments and a low elongation modulus filament are formed. A sheath portion made of filaments and an alternately wound structural yarn is formed. This alternately wound structured yarn has a core portion having fine crimps and a sheath portion having coarse crimps coexisting on the yarn surface, resulting in a texture similar to that of a spun yarn.

In the present invention, PBT is used as a filament with a high elongation modulus, and PET is used as a filament with a low elongation modulus. As for PETK, it is possible to use a polymer having a degree of polymerization which is normally used in the manufacture of commercially available polyester yarns, whereas for PBT, one having a degree of polymerization which is somewhat higher is used. Intrinsic viscosity measured with the preferred degree of polymerization of the polymer or using a solvent with a 50:50 weight mixing ratio of tetrachloroethane:7 enol, 0 for PET;
55-0.75. In the case of PBT, it can be 0.75 to 1.10.

Regarding the chemical composition, in order to maintain the excellent performance of each fiber, PETK glue consists of 85 moles or more of ethylene terephthalate units, and PBT has 85 moles or more of ethylene terephthalate units.
Although it is desirable that more than one unit is composed of tetramethylene terephthalate units, it is of course possible to add a small amount of copolymer component depending on the purpose.

For melt extrusion, a general screw extruder can be used, but in order to prevent thermal decomposition of the polymer, the temperature should not exceed 270°C for PBT and 31°C (1°C) for PET. It is desirable to perform melt extrusion.

The two components are spun simultaneously as independent threads using the same @melt spinning device, but the two threads may be spun from the same spinneret, or they may be spun from different spinnerets. You can take it out.

After the two threads are cooled, they are pulled together.

It is wound up at a speed of 1,100 to 2,500 m/min.

]100ff! If it is less than /min, the POT undrawn yarn wound on the drum during spinning and winding will naturally elongate in the longitudinal direction of the fiber. Established the current position through so-called spontaneous growth.

PB wrapped in a package when exceeding 2500 m1 minute
Tortoise that shrinks in the length direction of the fibers of undrawn T yarn! The force makes it difficult to attach and detach the package. In addition, large fine spots (Worcester's spots) in the length direction of the fibers also become large, which is not desirable. The spinning temperature is preferably in the range of 270 to 285°C in order to simultaneously spin both PET and PBT components.

The PET undrawn yarn and PBT undrawn yarn thus obtained each exhibit stress-strain curves as shown in FIG. The filament 1 with high elongation modulus in Figure 1 is PB.
T undrawn yarn, low elongation modulus filament 2 is PE
It is a T undrawn yarn.

The polyester filament undrawn yarn made of PBT and PET has too high a breaking elongation and cannot be used for practical use in clothing.

It is necessary to draw at 0.55 to 0.7 times the maximum draw ratio (maximum draw ratio that can be drawn without breaking) of the PBT undrawn yarn, which is the filament on the high elongation modulus side.1 Normal drawing method Although the PBT undrawn yarn is drawn uniformly, PET, which is a filament with a low elongation modulus,
Undrawn yarns cause necking stretching, making it impossible to obtain polyester filaments with uniform dyeability.

Therefore, in the present invention, polyester filaments with uniform dyeability can only be obtained by continuously performing drawing and false-twisting to create a crimped yarn at once by simultaneous drawing and false-twisting. It becomes.

False twisting temperature is 150~205℃, preferably 170~
It is necessary to set 200'CK.

If the temperature is less than 150°C, the dimensional stability and crimp performance of the resulting crimped yarn will be significantly reduced, and if it exceeds 205°C, fibers will fuse or untwist defects will occur.

The number of false twists may be determined by selecting conditions such that the twist angle calculated from D: fineness (denyl) of the crimped polyester yarn T: number of false twists (T/M) is 30° to 40'.

In the present invention, after mixing filaments with different elongation moduli, it is necessary to perform a false twisting process to form a double-layer twisted structure yarn during false twist heating, and by mixing filaments, the alternating winding after untwisting is reduced. The structure is stabilized, and it is possible to prevent the wound filament from slipping on the core due to ironing and deteriorating quality. The fiber mixing can be carried out, for example, by using a known fluid yarn entanglement processing device (Japanese Patent Laid-Open No. 54-2441) as shown in FIG.

The mixing ratio of PET undrawn yarn and PBT undrawn yarn is preferably 40:60 to 60:40 in terms of weight, but is not particularly limited to this.

One important point in the present invention is the use of PBT as the filament component on the high elongation modulus side. As is well known, when PBT is made into a crimped yarn, it exhibits excellent bulk and crimpability due to its high crystallinity, and also has excellent dispersion dyeing performance.

Therefore, P as a filament component with high elongation modulus
By using BT, a second-order effect can be obtained.

(1) The crimp performance of polyester crimped yarn is thicker (improved).

(2) PET as a filament component with a low elongation modulus and PBT as a filament component with a high elongation modulus have almost the same dispersion dyeability (deep dyeability), and the polyester crimped yarn does not produce shading when dyed.

〔Example〕

The present invention will be explained below with reference to Examples. Measurement of elongation modulus of undrawn filament, elongation rate, crimp rate, crimp recovery rate of crimped yarn, and dispersion dyeing are as follows:
The following method was used.

Elongation modulus: Stress 1.5 P in the stress-strain curve of unstretched filament measured by a conventional method in an atmosphere of 25°C and 65% RH
It is expressed as (J'/da・chi) assuming that the strain relative to /da is 8%.

Elongation rate CI, crimp rate CC, crimp recovery rate CR: Polyester crimped yarn was winded into 20 turns using a 1 tn frame circumference or setting machine, and treated in hot water at 90°C for 20 minutes. Then dry. Apply a load of 1±-i per tenil to this skein and measure the length after 000! . Let it be α. Next, add a load of 100P per tenile, and at this time measure the length of 000 and make it 1, cm. After this, remove the two loads mentioned above, leave it for 20 minutes, and then apply T per tenil again. Apply a load of , / and measure the length to obtain l, am.

The elongation rate CE, crimp rate CC, and elongation recovery rate CR are calculated using the following formulas.

Dispersion dyeing: The polyester crimped yarn knitted into a tubular shape was subjected to noping with an anionic activator 21/it at 100°C for 20 minutes,
Washed with water and dried. Next, Dianic Sprue BG
-FS (2-disperse dye manufactured by Mitsubishi Chemical Industries, Ltd.) 4% owf, )-
Hornult TD (Toho Kagakuten 2 Rōdan leveling dye) 0.51”
/II, Ultra MT4 #170 (manufactured by Miwajima Chemical t p
H regulator) 0,3 P/l in a dyebath with a bath ratio of 1:30.
The dyeing was carried out at 30° C. for 60 minutes, followed by reduction washing, water washing and drying according to conventional methods.

Example The intrinsic viscosity measured using a solvent with a 50:50 weight mixing ratio of tetrachloroethane and phenol was 0.68 and 0.68.
Polyethylene terephthalate and polytetramethylene terephthalate No. 95 were melt-spun using the melt-spinning apparatus shown in FIG. 3 at 280'''C using a 1:1 metering pump from the spinneret apparatus shown in FIG. Polyethylene terephthalate was spun into a 72-filament yarn and polytetramethylene terephthalate was spun into a 36-filament yarn.The yarn was cooled according to a conventional method, and after applying an oil agent, it was drawn and doubled. The fibers were mixed using the fluid system intertwining device shown in Figure 2, and wound up at 1800 ml per minute.

Separately, a polyethylene terephthalate filament and a polytetramethine/terephthalate filament were each independently wound at 1800 m/min, and the undrawn yarn filaments were evaluated.

What about the above polyethylene terephthalate and polytetramethylene terephthalate? The drawn filaments were drawn and simultaneously false-twisted using the apparatus shown in FIG. 5 to obtain a spun yarn-like polyester crimped yarn having an alternating winding structure of 220 denier/108 filaments/t. The results are shown in Table 1.

Comparative Example Using polyethylene terephthalate having an intrinsic viscosity of 0.68, it was melt-spun at 280° C. from a 36-hole spinneret in the melt-spinning apparatus shown in FIG. 6, and wound at 3200 m/min.

In addition, 180
It was wound up in 1 minute.

The two types of undrawn filaments were 118 denyl/36 filaments and 187 denyl/72 filaments, respectively. Next, these two types of undrawn filaments were subjected to simultaneous drawing and false twisting using the apparatus shown in FIG. 7 to obtain a spun yarn-like polyester crimped yarn having a double-wound structure of 223 denyl/108 filaments/t. I got it.

The two types of undrawn filaments were drawn and doubled, then mixed using a fluid system entanglement treatment device shown in FIG. 2, and then fed to a drawing and simultaneous false twisting device. The results are shown in Table 1.

Wind 1゜Table 1 [Effects of the Invention] According to the present invention configured as described above, it is possible to modify the package creel for undrawn yarn of the conventional drawing and simultaneous false twisting processing machine. This method has an exceptional effect in that a spun yarn-like polyester crimped yarn having both high performance and deep dyeing and level dyeing properties can be obtained.

[Brief explanation of the drawing]

Fig. 1 shows a stress stress curve for explaining the elongation modulus of undrawn filaments of PBT, PE, and T in the present invention, and Fig. 2 shows a cross section of an example of the fluid yarn entanglement processing device used in the present invention. 3, 4, and 5 are schematic diagrams of the melt spinning device, spinneret, and simultaneous drawing and false twisting device used in the examples of the present invention, and FIG. 6 and 7 are schematic diagrams of the FIG. 2 is a schematic diagram of a melt spinning device and a drawing and simultaneous false twisting device used in a comparative example. 1°.-PBT component, 2...PET component. 3゛°゛Compressed air, 4゛゛Filament 5...゛Extruder, 6゛°゛Polymer line. 7... Spinneret, 8... Spinneret device. 9 pa/undrawn yarn bobbin package. 10...Spinneret plate, 11...°r applicable wire mesh 12-°
° Hot plate of false twisting machine. 13° false twist spindle, 14° crimped yarn. 15... Fluid system filament entanglement processing device → 1 time + 4 figures + 5 times Blue 6 figure Blue 712]

Claims (1)

[Claims] A polyester mainly composed of ethylene terephthalate units and a polyester mainly composed of tetramethylene terephthalate units were simultaneously spun into independent threads using the same melt-spinning equipment, and then doubled and mixed to produce an undrawn polyester thread. A method for producing a spun yarn-like polyester crimped yarn, which is characterized by carrying out false twisting at the same time as drawing.