JPH0238700B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyester multifilament mixed yarn of different fineness having silk-like characteristics and a method for producing the same, and more specifically, the present invention relates to a mixed fiber yarn of ultra-fine filaments of 0.8 denier or less and thick filaments of 1.5 denier or more, and The present invention relates to a polyester multifilament latent crimp yarn having latent crimp ability and a method for producing the same. Typical methods for imparting silk-like properties to polyester multifilament include creating a triangular cross-section, applying a weight-reducing process to the fabric, and using crimped yarn or differential shrinkage yarn. It has been implemented. Although approaches to silk have been achieved to some extent using these methods, they have not yet achieved sufficient silk-like properties. In order to improve this drawback, JP-A-50-116749 further analyzed silk and found that the cocoon thread's non-uniform micro-crimps, low shrinkage, and mixed fineness play a major role in the characteristics of silk fabrics. The filaments are made of filaments that have a difference in heat shrinkage rate along the length direction of each filament and a difference in fineness of 1 denier or more in the range of 1 to 6 denier, and are made bulky by heat treatment. A special crimped yarn is disclosed that has a latent crimp ability that can be crimped. The yarn has non-uniform fine crimps similar to cocoon yarn, and due to the mixed fibers of different fineness, it has non-uniform large and small crimps even more similar to cocoon yarn, so it has improved silk-like properties. However, the filament denier of the yarn is 1
Because it combines filaments in the range of ~6 deniers, knitted fabrics obtained using this yarn have a rough and hard surface, and have the disadvantage that they do not have sufficient silk-like surface softness and softness. have. On the other hand, in recent years, it has become common to reduce the denier of the filaments constituting multifilaments to make them softer and softer. In particular, ultrafine filaments of less than 1 denier are significantly softer and softer than filaments of 1 denier or more, and polyester multifilaments having ultrafine filaments of less than 1 denier are also produced. However, yarns made only of ultra-fine filaments have the problem of lacking tension and stiffness, which are important properties when made into knitted fabrics. The present inventors have arrived at the present invention as a result of intensive studies aimed at improving these drawbacks and obtaining a yarn with even more improved silk-like properties. That is, the object of the present invention is to provide a latent crimped yarn that has a soft surface touch, elasticity and tension that are important for knitted fabrics, and also has silk-like non-uniform fine crimps and bulkiness, and a method for producing the same. It is in. The latent crimped yarn of the present invention has the following configuration in order to achieve the above object. A polyester multifilament in which one filament of 0.8 denier or less and the other filament of 1.5 denier or more are mixed together and have substantially no slack or fuzz, and one group of filaments and the other filament A latent crimp yarn with a shrinkage stress difference of 0.08 g/d or less between groups, and a non-uniform heat shrinkage rate in the longitudinal direction of the filaments constituting the yarn and between each filament in the same cross section of the yarn. be. The latent crimped yarn of the present invention will be explained in more detail. The latent crimped yarn according to the present invention needs to be a mixture of one filament of 0.8 denier or less and the other filament of 1.5 denier or more. The softness and softness of the surface of the knitted fabric,
In order to provide drape, etc., it is important to have ultra-fine filaments of 0.8 denier or less.
In addition, in order to provide appropriate tension, waist, and resilience,
It is important that a thick filament of 1.5 denier or more is present. When using any combination of filaments of more than 0.8 denier and less than 1.5 denier and knitted with different fibers of different fibres, the surface touch will be soft, the softness will be low, and the tension will be poor.
Lower back, resilience becomes low. In order to further improve the above characteristics, it is preferable that ultrafine filaments of 0.8 denier or less and filaments of 2.0 denier or more are mixed. It has been known that when yarns of different fineness are drawn together and drawn, a large amount of sag occurs, which significantly deteriorates workability and the resulting yarn has large sag, which significantly deteriorates the ability to pass through higher processes. . The present inventors have discovered that if the shrinkage stress difference between one filament group and the other filament group is set to 0.08 g/d or less, the passability to higher-order processes becomes very good. It has been found that it is more preferable that the shrinkage stress difference is 0.05 g/d or less in order to further improve the above effects and prevent problems even if delayed shrinkage occurs during long-term storage. The latent crimped yarn of the present invention needs to have non-uniform heat shrinkage in the length direction of the filament and between each filament in the same cross section. When post-heat treatment is performed in the next step, the non-uniform heat shrinkage results in the non-uniform fine crimp and good bulkiness that are characteristic of silk. In the present invention, the term "nonuniform heat shrinkage rate in the longitudinal direction of the filament" is defined as follows. Carefully take out one filament and the other filament from the non-uniformly heat-treated multi-filament yarn without applying any tension as much as possible, and cut each filament of one filament and the other filament approximately 3 cm at 20 arbitrary points.
Fix one end of each with a pin clip and the other end with a load of 0.1 g/d, and measure the length L ₁ of the filament between the pin clip and the 0.1 g/d load using a cassette meter under a load of 0.1 g/d. Read it. In this case, L ₁ should be 2.0 to 2.5 cm. Next, the distance between the pin clip and the 0.1 g/d load was set at 200℃ for 5 minutes with the filament slackened so that the filament could sufficiently shrink due to heat treatment. Read the length L ₂ of the filament in between using a cassette meter. The dry heat shrinkage rate of the filament is determined by the following formula, the measured values show a distribution, and the average difference between the maximum value and minimum value of each of the 10 filaments of one filament and the other filament is 3% or more,
The filament is defined as having a non-uniform heat shrinkage rate in the longitudinal direction if it is preferably 5% or more. Dry heat shrinkage rate of filament (%)=L ₁ −L ₂ /L ₁ × 100 In the present invention, the term ``unequal heat shrinkage rate among filaments within the same cross section'' is defined as follows. The multi-filament yarn subjected to non-uniform heat treatment is cut into approximately 3 cm pieces at arbitrary points, and all the filaments are separated by applying as little tension as possible, and divided into one filament group and the other filament group. Next, the dry heat shrinkage rate of each separated whole filament of one filament group and the other filament group was measured using the same measuring method as the dry heat shrinkage rate of the same filament in the length direction as described above,
The measured values of one filament group and the other filament group each show a distribution, and the average difference between the maximum and minimum dry heat shrinkage rates of the filaments at each cross section is 3% or more in the measurements at 10 locations. , preferably 5% or more, is defined as non-uniform heat shrinkage among filaments having the same cross section. In addition, the latent crimped yarn according to the present invention has the effect of developing bulk by post-heat treatment in the next step, and can obtain silk-like or even superior bulkiness, and the bulkiness level can be increased to 10c by post-heat treatment. There are effects such as an increase of more than .c./g. The cross-sectional shape of the latent crimped yarn according to the present invention may be a round cross-section or an irregular cross-section, but the softness of the surface touch,
In order to further improve softness and give silk-like luster, it is preferable that one filament, which is an ultra-fine filament, has a round cross-sectional shape, and the other filament has an irregular cross-sectional shape, particularly a trilobal cross-section. Further, the TiO ₂ content of the polyester constituting the latent crimped yarn of the present invention may be of any value, but in order to improve the silk-like luster, polyester containing a small amount of TiO ₂ or polyester containing no TiO ₂ is used. It is preferable. Further, the polyester constituting the latent crimped yarn of the present invention contains 80 mol% or more of ethylene terephthalate units. Copolymerization components include, for example, dibasic acids such as adipic acid, sebacic acid, isophthalic acid, diphenyl dicarboxylic acid, and naphthalene dicarboxylic acid, oxyacids such as oxybenzoic acid, and diethylene glycol, propylene glycol, neopentyl glycol, and pentyl glycol. One or more types of glycols such as erythritol and polyethylene glycol monomethyl ether can be used. It is preferable that the latent crimped yarn according to the present invention is interlaced in terms of passability through higher-order processes. In this case, the CF value according to the measurement method described later is 5.
It is preferably 300 to 300, more preferably 10 to 250. If the CF value is less than 5, the interlacing effect will be small, and if the CF value exceeds 300, the resulting fabric will tend to become irritated and the quality of the knitted fabric will tend to deteriorate. Next, the method for producing the latent crimped yarn of the present invention will be described. The method for producing a latent crimped yarn of the present invention has the following configuration. In other words, after drawing, one filament
At least two types of undrawn polyester filament yarns, each of which has a denier of 0.8 denier or less, the other filament has a denier of 0.5 denier or more, and the difference in stretching tension between one filament group and the other filament group at the same stretching ratio is 0.5 g/d or less. Align and stretch the
After running the filaments in a relaxed state in contact with the first heating body to give non-uniform heat shrinkage rates in the longitudinal direction of the filaments constituting the yarn and between each filament in the same cross section of the yarn, the first heating body This is a method for producing a latent crimped yarn, characterized in that heat treatment is performed using a second heating element at a low temperature. The manufacturing method of the present invention will be described in more detail using the drawings. FIGS. 1 and 2 are schematic illustrations of a preferred stretching process used in the present invention. In FIG. 1, 1 is a polyester multifilament undrawn yarn made of one filament, 2 is a polyester multifilament undrawn yarn made of the other filament, and after they are aligned through guides 3 and 4, rollers 5 and 7 The filament is stretched through a heating pin 6 between the filaments, and the first heating element 8 is run in a relaxed state between the rollers 7 and 9 to draw the filament unevenly in the length direction of the filament and between each filament in the same cross section. A second heating element 10 is used between the rollers 9 and 11 to eliminate the slack and loops generated in the above process.
Wind it up to 2. Further, in FIG. 2, roller 11 and roller 14 are shown after being treated in the same manner as described above.
In this method, interlace processing is performed using an interlace nozzle 13 between the paper and the paper, and the film is wound on a winder 12. The polyester multifilament undrawn yarn supplied in the production method of the present invention comprises at least two types of polyester multifilament undrawn yarn, one filament having a filament denier of 0.8 d or less and the other filament having a filament denier of 1.5 d or more after drawing. It is more preferable to supply an undrawn polyester multifilament yarn in which one filament has a denier of 0.8 denier or less and the other filament has a denier of 2.0 denier or more after drawing. In the manufacturing method of the present invention, the difference in stretching tension between one filament group and the other filament group between the heating pin 6 and roller 7 must be 0.5 g/d or less. If the difference in stretching tension exceeds 0.5 g/d, the difference in elastic recovery rate due to the difference in stretching tension will increase, and the occurrence of sagging will increase.
In addition to the fact that the workability is significantly deteriorated due to reverse winding, etc., the slack remains in contact with the first heating element 8 when it runs in contact with the first heating element 8 in a relaxed state, which will be described later. If the obtained yarn is subjected to post-heat treatment in the next step, the silk-like fine crimp that is the objective of the present invention cannot be obtained, and the shrinkage stress difference of the obtained yarn is less than 0.08 g/d. I'll go beyond it.
Therefore, the difference in stretching tension is set to 0.5 g/d or less.
In order to match the stretching tensions of both components, the spinning speeds of both components are appropriately changed. In the manufacturing method of the present invention, after drawing and stretching,
It is necessary to run the rollers 7 and 9 in contact with the first heating element 8 in a relaxed state. If the filament is made to run in contact with the first heating element 8 in a fixed length or under tension, it is impossible to give uneven heat shrinkage to each filament in the length direction and in the same cross section, so that the resulting yarn is When heat-treated, silk-like fine crimp and bulkiness, which are the objectives of the present invention, cannot be obtained. Furthermore, if an interlace nozzle is used between the roller 7 and the first heating element 8, the direction will be to suppress reverse winding on the roller 7, so even if an interlace nozzle is provided between the roller 7 and the first heating element 8, good. Particularly in the case of a mixed fiber yarn consisting of a group of ultra-fine filaments of 0.8 denier or less and a group of thick filaments of 1.5 denier or more, both filaments tend to separate, so an interlace nozzle is provided between the roller 7 and the first heating element 8 to It is preferable to migrate to Furthermore, if the yarn having loops or slack generated on the first heating element 8 is wound as it is between the rollers 7 and 9, the unwinding property of the wound yarn will deteriorate and the yarn will pass through the higher stage process. sex deteriorates significantly,
It is important to eliminate loops and slack that occur between rollers 7 and 9. At this time, the temperature of the second heating element 10 must be lower than the temperature of the first heating element 8 in order to eliminate loops and slack. When the temperature of the second heating body 10 is higher than the temperature of the first heating body, the uneven heat contraction once applied to each filament in the length direction of the filament and in the same cross section becomes uniform, so that the obtained yarn If the strip is post-heat-treated, the silk-like fine crimp and bulkiness that are the objectives of the present invention cannot be obtained. In addition, in the manufacturing method of the present invention, as shown in FIG. 2, if the yarn exiting the roller 11 is interlaced, the passability to higher-order processes becomes very good. It is preferable to perform interlacing via 13. In this case, the measurement method described later is used.
It is preferable that the CF value is 5 to 300. Further, it is preferable to use an interlaced nozzle that substantially does not generate fuzz even when interlaced with a CF value of 5 to 300. In particular, filaments of 0.8 denier or less have a problem that they tend to become fluffy during entangling treatment compared to ordinary filaments, so it is preferable to use a nozzle whose inner surface of the yarn passage is made of ceramics. As detailed above, the latent crimped yarn obtained by the present invention not only has good luminosity close to that of natural silk, but also has a mixture of ultra-fine filaments and thick filaments, and when made into a knitted fabric, it resembles silk. It has a soft, vertical surface and is firm.
This provides a knitted fabric that has good elasticity, resilience and appropriate drapability. In addition, the latent crimped yarn obtained in the present invention has a non-uniform heat shrinkage rate in the length direction of the filament and between each filament in the same cross section. A knitted fabric having similar fine crimp and good bulkiness can be obtained. Furthermore, the latent crimped yarn obtained by the present invention has no fluff or sag, and therefore has good passability through higher-order processes, and the interlaced latent crimped yarn has even better passability through higher-order processes. . That is, when the latent crimped yarn obtained according to the present invention is dyed as a knitted fabric, an extremely excellent knitted fabric having an aesthetic appearance and feel similar to natural silk can be obtained. Various measurement methods in the present invention are as follows. (Method for Measuring Shrinkage Stress) After separating the latent crimped yarn of the present invention into one filament group and the other filament group without applying tension as much as possible, the Sampling 10 samples each on a 30cm sample. Next, tie both ends of each sample to make 10 skeins of about 10 cm each. Manufactured by Kanebo Engineering Co., Ltd. shown in Figure 3
The sample was measured using a KE-type shrinkage stress measuring device.
15 to the upper hook 16, and after setting the initial load to 0.033 g/d with the lower hook 17, the heater 18,
From room temperature at 18' with a heating rate of 2.5℃/sec.
It is heated to around 250°C, and changes in shrinkage force are detected with a U gauge 19 and recorded on an XY recorder 20. The method is repeated for other samples. Read the Max stress from the chart and find the average value of 10 samples of each filament group. The shrinkage stress difference is determined by the following formula. Shrinkage stress of one filament group (g/d) = Average value of 10 samples of one filament group (g)/2 x Denier of one filament group (d) Shrinkage stress of the other filament group (g/d) = Average value of 10 samples of the other filament group (g)/2 x Denier of the other filament group (d) Shrinkage stress difference (g/d) = | Shrinkage stress of one filament group (g/d) - the other The shrinkage stress of the filament group (g/d
) | (Method of measuring CF value) The CF value was measured by a method according to US Pat. No. 3,290,932. The outline is shown below. In the apparatus shown in FIG. 4, a sample 21 is unwound by a roller 22 and wound around a waist roller 23. Thread 1cm/
The magnetic tension applying device 24 is adjusted while running at a speed of sec to set the tension between the tension applying device 24 and the roller 22 to the initial tension. The initial tension is denier x 0.2 g, and is fixed between the tension applying device 24 and the roller 22. It is detected by the tension meter 25. After setting the initial tension, the running of the thread is stopped, and the measuring needle 26 is inserted into the thread at a position approximately bisecting the thread as shown in FIG. Then, add 1 piece of sample thread.
When running again at cm/sec, the needle catches on the interlacing point 27 and the tension between the needle 26 and the roller 22 increases. The roller 22 is set to stop when the tension value reaches [initial tension + (average denier of filament of 0.8 denier or less) x 1 g], and the thread travels from the time the needle is inserted until it stops again. The moving distance li (mm) is read from the rotation angle of the roller 22. Repeat the same operation 40 times and the CF value is []
Calculate by formula. The measurement was performed with n=3 and the average value is displayed. The CF value in the present invention is the Entanglement Tester manufactured by Rhthschild (model R2040) manufactured based on the above principle.
The measurements were carried out using The present invention will be specifically explained below using Examples. Example 1 [η] = 0.64 and polyethylene terephthalate containing no TiO ₂ was melt-spun at the spinning speed and cross-sectional shape shown in Table 1, and undrawn yarn of one filament (A) shown in Table 1 was obtained. Then, an undrawn yarn of the other filament (B) was obtained. The undrawn yarns of (A) and (B) were aligned, and using the apparatus shown in Figure 1, the drawing speed was 300 m/min, the drawing ratio was 2.80,
Stretched at a hot pin temperature of 100℃, relaxation rate 10%,
However, relaxation rate (%) = Speed of roller 7 (m/min) - Speed of roller 9 (m/min) / Speed of roller 7 (m/min)
After running in contact with the first heating element at 215℃ at ×100, heat treatment was performed with the second heating element at 150℃ in a constant length state.
It was wound up in a winder to obtain latent crimped yarns of Experiment Nos. 1 to 13 in Table 1. In addition, after applying interlacing using the device shown in Figure 2, it was wound up in a winder and experiment Nos. 14 to 17 in Table 1.
A latent crimped yarn shown in Figure 1 was obtained. Furthermore, in the apparatus shown in FIG. 2, a first heating element 8, a roller 9, a second heating element 10, a roller 11
After drawing the yarn between rollers 5 and 7 without using a roller, interlacing treatment was performed directly, and the mixed yarn of Experiment No. 18 was obtained by winding the yarn in a winder. When these latent crimped yarns were woven and high-level evaluation was performed, the results shown in Table 1 were obtained. In addition, in Table 1, Experiment No. 1, 2, 3, 7,
12 and 18 are comparative examples for clarifying the present invention. In Table 1, in Experiments Nos. 1 to 6, the filament deniers of (A) and (B) were changed and drawing was carried out in various combinations. In Experiment No. 1, one filament (A) was over 0.8 denier, so when it was made into a woven fabric, the surface touch was not soft, and the other filament was less than 1.5 denier, so it did not have stiffness or tension, making it a good woven fabric. Nakatsuta. In Experiment No. 2, one filament (A) was less than 0.8 denier, resulting in a fabric with a very soft surface touch, but the other filament (B) was less than 1.5 denier, so the resulting fabric had poor waist and tension. I was bored. In Experiment No. 3, the other filament (B) had a denier of 1.5 denier or more, so it had good elasticity and tension, but the fabric lacked softness in the surface touch because one filament (A) had a denier of more than 0.8 denier. It became. Experiments No. 7 to 12 in Table 1 are the other filament (B)
Stretching was carried out using undrawn yarn with different spinning speeds. In Experiment No. 7, the drawing tension of the other filament (B) was low because the spinning speed of the other filament (B) was low, and the drawing tension difference with one filament (A) exceeded 0.5 g/d. The other filament (B), which was lower, was likely to cause reverse winding on the roller, resulting in poor workability. In addition, since the other filament (B) has a large amount of slack, there are many parts that are not heat-treated by the first heating element, making it impossible to obtain silky fine crimp and good bulkiness. As a result of high-level evaluation of the obtained yarn, which did not disappear by heat treatment with a two-heating body, it was found that its passability through higher-level processes was poor. On the other hand, in Experiment No. 12, the drawing tension of the other filament (B) was greater than that of one filament (A), and the difference in drawing tension exceeded 0.5 g/d, so one filament (A) was reversed against the roller. In addition to being easy to wind and having poor workability, one of the filaments (A) has a large amount of slack, which means that there are many parts that are not heat-treated by the first heating element, resulting in silk-like fine crimp and bulkiness. was not obtained, and the difference in shrinkage stress between one filament group and the other filament group exceeded 0.08 g/d.
Furthermore, since one of the filaments (A) had a large amount of slack, it was difficult to remove the slack with the second heating element, resulting in a yarn with slack. As a result of the higher-order processing of the yarn, one of the filaments (A) became sagging and fluffed, resulting in extremely poor passability through higher-order processing. In addition, since Experiment No. 18 was a mixed fiber yarn that had not been subjected to the relaxation heat treatment using the first heating element, which is a feature of the present invention, the fabric obtained using the yarn had a soft surface touch and Although it had a waist, it lacked the bulkiness of silk and was paper-like. Furthermore, since the fabric was obtained from a mixed yarn with a large shrinkage stress difference between one filament and the other filament and slack, processability was unstable and the surface quality of the fabric was poor. On the other hand, Experiment Nos. 4, 5, which meet the requirements of the present invention
The latent crimped yarns of Nos. 6, 8, 9, 10, 11, 13, 14, 15, 16 and 17 have good passability through higher steps and can be made into woven fabrics.
High-level evaluation revealed that an excellent fabric was obtained that had a luster similar to natural silk, a soft surface touch, tension, and elasticity, as well as silk-like non-uniform fine crimps and good bulk. Ta. However, experiments No. 9 and 13 in Table 1
is one filament (A) and the other filament
Stretching was carried out using an undrawn polyester multifilament yarn having the same round cross-sectional shape as in (B). As a result of high-level evaluation of the obtained latent crimped yarn, a fabric with good luster was obtained; however,
Compared to the fabrics of Experiment Nos. 8 to 11, the silk-like luster was a little lacking. Further, in Experiment Nos. 14 to 17 in Table 1, interlacing was performed by changing the air pressure. Experiment No.17
has a high CF value, so when it was made into a fabric, it was slightly irritated.

【table】

[Table] Irritation of the fabric ◎Good with no irritation ○Good with some irritation

[Brief explanation of drawings]

Figures 1 and 2 are schematic diagrams of a preferred stretching process used in the present invention, Figure 3 is a schematic diagram of a shrinkage stress measuring device, Figure 4 is a schematic diagram of a CF value measuring device, and Figure 5 is a schematic diagram of a CF value measuring device.
The figure is an enlarged view of the needle portion in FIG. 4. 1: Polyester multifilament undrawn yarn consisting of one filament (A), 2: Polyester multifilament undrawn yarn consisting of the other filament (B), 3, 4: Guide, 5, 7,
9, 11, 14: roller, 6: heat pin, 8: first heating body, 10: second heating body, 12: winder.

Claims (1)

[Claims] 1. One filament of 0.8 denier or less and 1.5
The polyester multifilament is a polyester multifilament in which the other filaments of denier or higher are mixed together and have virtually no slack or fluff, and the difference in shrinkage stress between one filament group and the other filament group is 0.08 g/ d or less, and has a non-uniform heat shrinkage rate in the longitudinal direction of the filaments constituting the yarn and between each filament in the same cross section of the yarn. 2. The latent crimped yarn according to claim 1, wherein one filament has a round cross section and the other filament has a trilobal cross section. 3. The latent crimped yarn according to claim 1 or 2, which is interlaced. 4 After drawing, one filament becomes 0.8 denier or less, the other filament becomes 1.5 denier or more, and the difference in drawing tension between one filament group and the other filament group at the same drawing ratio is
At least two types of polyester multifilament undrawn yarns having a weight of 0.5 g/d or less are aligned and drawn,
After running the filaments in a relaxed state in contact with the first heating body to give non-uniform heat shrinkage rates in the longitudinal direction of the filaments constituting the yarn and between each filament in the same cross section of the yarn, the first heating body A method for producing a latent crimped yarn, which comprises performing heat treatment with a low-temperature second heating element. 5 Of the two types of polyester multifilaments, one filament has a round cross section and the other filament has a trilobal cross section.
2. Method for producing a latent crimped yarn as described in Section 1.