JP2005350780A - Conjugate fiber for woven fabric and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polytrimethylene terephthalate-based conjugate fiber, without forming band-like unevenness or line-like defects of its fabric and exhibiting an excellent stretching quality and soft touch feeling. <P>SOLUTION: This conjugate fiber of which at least one of the components is the polytrimethylene terephthalate satisfies the following (1) to (6) conditions. (1) The cross sectional shape of its single fiber has <1.2 flatness. (2) The degree of flexible stretch (DCE<SB>10</SB>) after its dry heat treatment at 90°C under 8.9×10<SP>-3</SP>cN/dtex loading weight is ≥10 %. (3) The apparent crimp rate is ≥15 %. (4) The ratio of cross sectional areas of the maximum and minimum of constituting single fibers is ≤2.0. (5) The fineness variation value U % measured by a normal method is ≤1.2. (6) In the fineness variation value U % chart measured by an inert method, the crest and trough difference of continuous wave shape in yarn length direction is ≤8 % based on the mean dtex value, provided that the measurement of the fineness variation value U % is performed over 2,000 m yarn length. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polytrimethylene terephthalate composite yarn suitable for textile use and a method for producing the same. More specifically, a polytrimethylene terephthalate-based composite yarn that exhibits excellent quality, soft texture and good stretch properties without causing streak-like defects when used for warp and industrially stable it. The present invention relates to a manufacturing method for manufacturing.

In recent years, there has been a strong demand for knitted fabrics, especially stretch knitted fabrics having a stretch performance.
In order to satisfy such a demand, for example, a large number of knitted fabrics that are given stretch properties by blending polyurethane fibers are used.
However, polyurethane fibers are difficult to be dyed with polyester dyes, so that the dyeing process becomes complicated, and the fibers become brittle and deteriorate in performance due to long-term use.
In order to avoid such drawbacks, application of polyester fiber crimped yarn instead of polyurethane fiber has been studied.
In recent years, a PTT crimped yarn has been proposed by paying attention to the stretch recovery property of polytrimethylene terephthalate (hereinafter referred to as “PTT”).
In particular, many latent crimped fibers have been proposed in which two types of polymers are bonded side-by-side or eccentrically to develop crimps after heat treatment.

In Patent Documents 1 and 2, a side-by-side type two-component composite yarn using PTT for at least one component or PTT having different intrinsic viscosities for both components, and an eccentric sheath-core composite yarn ( Hereinafter, both are referred to as PTT composite yarns). This PTT composite yarn is characterized by a soft texture and good crimp expression. These prior arts describe that they have stretchability and stretch recovery, and can be applied to various stretch knitted fabrics or bulky knitted fabrics by utilizing these properties.
In particular, Patent Document 2 discloses a PTT-based composite yarn that has a high crimp before boiling water treatment and is excellent in bulkiness. However, the composite yarn disclosed in the publication is applied to fabrics such as taffeta. When used, the bulkiness is excessive and the fabric has a sense of depth, and there is a problem that it is restricted from being developed in fields requiring flatness and lightness, such as women's clothing lining with a cover factor of about 2000 or less. It was.

On the other hand, Patent Document 3 discloses that a beautiful fabric surface is obtained by setting the Wooster spots of the PTT composite yarn to 2.0% or less. However, even if the Wooster spot is 2.0% or less, band-like dye spots may occur on the fabric. In the measurement of Wooster spots, it is clear from the study by the present inventors that just measuring the spots for a yarn length of 50 to 100 m in the normal mode as disclosed in Patent Document 3 does not match the dyeing quality of the fabric. Became. That is, in order to join two components having different melt viscosities, PTT composite yarns may cause irregular fineness fluctuations in the yarn length direction, and further improvements have been demanded.
It has been clarified that such irregular fineness variation in the yarn length direction cannot be determined unless Worcester spots are measured in the inert mode over at least the yarn length of about 2000 m.

Furthermore, Patent Document 4 discloses a PTT composite yarn having a flat cross section such as a snowman type or an elliptical type. However, in the cross section of the snowman type or the elliptical type as disclosed in the patent document, the joint surface tends to be non-uniform in the yarn length direction, and as a result, the cross-sectional areas of the single yarns constituting the composite yarn become uneven. Due to such non-uniformity, it has been clarified that the fineness variation value U% exceeds 1.2%, the fineness varies in the yarn length direction, and band-like defects occur.
Therefore, there is no appearance of band-like spots or streak-like defects used in woven fabrics, the appearance of PTT composite yarns that have good surface flatness and surface quality, and can exhibit moderate warp stretchability. There was a strong demand.

Japanese Patent Publication No. 43-019108 JP 2002-061031 A JP 2001-055634 A JP 2002-180332 A

An object of the present invention is to eliminate surface quality defects due to the occurrence of band-like spots and streaks in fabrics.
An object of the present invention is to provide a PTT-based composite yarn and a method for producing the same that have good surface quality in a woven fabric and can exhibit appropriate stretch properties.

As a result of intensive studies to solve the above problems, the present inventors have found that the fineness variation value U% can be dramatically improved by specifying the polymer discharge conditions and the cooling conditions in the production of the PTT composite yarn. The headline and the present invention were completed.
That is, the first invention of the present invention comprises a single yarn group in which two polyester components are bonded to a side-by-side type or an eccentric sheath core type, and at least one component constituting the single yarn is polytrimethylene terephthalate. The polytrimethylene terephthalate composite yarn is characterized by satisfying the following requirements (1) to (6).
(1) The cross-sectional shape of the single yarn has a flatness of less than 1.2. (2) The stretch / elongation ratio (DCE ₁₀ ) after dry heat treatment at 90 ° C. under a load of 8.9 × 10 ⁻³ cN / dtex. 13% or more (3) The actual crimp rate is 15% or more (4) The maximum and minimum cross-sectional area ratio of the single yarn constituting the material is 2.0 or less. (5) The fineness variation value U% measured by the normal method is 1 .2 or less (6) In the fineness fluctuation value U% chart measured by the inert method, the difference between the peaks and troughs of the continuous waveform in the yarn length direction is 8% or less with respect to the average decitex (however, the fineness fluctuation value U% Is measured over a yarn length of 2000 m)

The second invention of the present invention comprises a single yarn group in which two polyester components are bonded to a side-by-side type or an eccentric sheath core type, and at least one component constituting the single yarn is polytrimethylene terephthalate. A method for producing a polytrimethylene terephthalate composite yarn, which satisfies the following requirements (A) to (G) when producing a composite yarn.
(A) The two polyester components melt at an intrinsic viscosity difference of 0.2 to 0.9.
(B) The polymer discharge linear velocity per discharge hole is discharged at 4 to 9 m / min.
(C) The heat insulation area | region from a spinneret surface to a cooling start shall be 50-150 mm.
(D) Change the time variation of the cooling air within 0.05 m / sec.
(E) The variation in the vertical and horizontal directions of the cooling air blowing surface is within 0.05 m / second.
(F) The distance from the cooling air blowing surface to the fiber is 1 to 60 mm.
(G) The distance from the spinning nozzle to the focusing position is 50 to 200 cm.

  ADVANTAGE OF THE INVENTION According to this invention, the PTT type | system | group composite thread | yarn most suitable for the background stretch fabric which has favorable surface quality and moderate stretch property, and the manufacturing method which manufactures it were able to be provided.

Hereinafter, the present invention will be described in detail.
The present invention is a composite yarn comprising a single yarn group in which two polyester components are bonded to a side-by-side type or an eccentric sheath core type, and at least one component constituting the single yarn is PTT, Intended is a PTT composite yarn whose component is other polyester.
That is, a combination of PTT and another polyester, or a combination of PTTs is targeted.
At least one of the single yarns constituting the PTT composite yarn in the present invention is a PTT homopolymer or a copolymerized polytrimethylene terephthalate containing 10 mol% or less of other ester repeating units.

Typical examples of the copolymer component include the following.
Acidic components include aromatic dicarboxylic acids typified by isophthalic acid and 5-sodiumsulfoisophthalic acid, aliphatic dicarboxylic acids typified by adipic acid and itaconic acid, and the like. Examples of the glycol component include ethylene glycol, butylene glycol, polyethylene glycol, and the like. Examples thereof also include hydroxycarboxylic acids such as hydroxybenzoic acid. A plurality of these may be copolymerized.
Other polyester components of the single yarn constituting the PTT composite yarn include PTT, polyethylene terephthalate (hereinafter referred to as “PET”), polybutylene terephthalate (hereinafter referred to as “PBT”), or these. What copolymerized three components is used.
Typical examples of the copolymer component include the following.
Examples of the third component include aromatic dicarboxylic acids typified by isophthalic acid and 5-sodium sulfoisophthalic acid, aliphatic dicarboxylic acids typified by adipic acid and itaconic acid, and the like as acidic components. Examples of the glycol component include ethylene glycol, butylene glycol, polyethylene glycol, and the like. Examples thereof also include hydroxycarboxylic acids such as hydroxybenzoic acid. A plurality of these may be copolymerized.

The manufacturing method of the PTT polymer used for this invention may be a well-known thing. A one-stage method in which the degree of polymerization corresponding to a predetermined intrinsic viscosity is obtained only by melt polymerization, or the degree of polymerization is increased by melt polymerization up to a certain intrinsic viscosity, and then the degree of polymerization corresponding to a predetermined intrinsic viscosity is obtained by solid phase polymerization. It is a two-stage method to raise.
A two-stage method combining the latter solid phase polymerization is preferred for the purpose of reducing the content of the cyclic dimer.
When the degree of polymerization is set to a predetermined intrinsic viscosity by the one-stage method, it is desirable to reduce the cyclic dimer by an extraction process or the like before supplying to the spinning.
The PTT polymer used in the present invention preferably has a trimethylene terephthalate cyclic dimer content of 2.5% by weight or less. More preferably, the content of trimethylene terephthalate cyclic dimer is less than 1.1% by weight. A more preferable trimethylene terephthalate cyclic dimer content is 1.0% by weight or less.

In the present invention, it is preferable that both components constituting the single yarn are PTT. When both of the components are PTT, an excellent stretch back property can be expressed.
When both components are PTT, the content of trimethylene terephthalate cyclic dimer is 1.1% by weight or less for the purpose of reducing the cyclic dimer content in the composite yarn. desirable.
The average intrinsic viscosity of the PTT composite yarn in the present invention is preferably in the range of 0.6 to 1.2 dl / g.
When the average intrinsic viscosity is less than 0.6 dl / g, the strength of the resulting composite yarn is low, the mechanical strength of the fabric is lowered, and the use for sports applications that require strength is restricted. When the average intrinsic viscosity exceeds 1.2 dl / g, yarn breakage occurs at the production stage of the composite yarn, and stable production becomes difficult. A preferred average intrinsic viscosity is 0.7 to 1.2 dl / g. Further, the difference in intrinsic viscosity between the two components at that time is more preferably 0.2 to 0.9 dl / g.

In the present invention, the blending ratio of the two polyester components in the single yarn cross section is preferably such that the ratio of the high viscosity component to the low viscosity component is 40/60 to 70/30. When the ratio of the high viscosity component is less than 40%, the yarn strength becomes less than 2 cN / dtex, and the tear strength of the fabric becomes insufficient. On the other hand, if the ratio of the high viscosity component is larger than 70%, the crimping performance is lowered. A more preferable blending ratio is 45/55 to 65/35.
In the present invention, the cross-sectional shape of the single yarn needs to have a flatness of less than 1.2. When the cross-sectional shape of the single yarn is a flatness of 1.2 or more, the quality of the surface such as smoothness and gloss is lowered when the woven fabric is used.

In the present invention, it is necessary that the dry heat 90 ° C. expansion and contraction rate is 10% or more. When the dry heat 90 ° C. stretch elongation rate is less than 10%, sufficient warp stretch does not appear when used for warp. A preferable dry heat 90 ° C. stretching elongation is 13% or more.
In the present invention, it is necessary that the actual crimp rate is 15% or more. When the actual crimp rate is less than 15%, the warp becomes remarkable when used for warp, resulting in a quality defect. A preferable actual crimp rate is 20% or more.
In the present invention, it is necessary that the cross-sectional area ratio of the single yarn constituting the composite yarn is 2.0 or less at the maximum. When the cross-sectional area ratio is larger than 2.0, the variation in crimping in the yarn length direction is increased, and the surface quality of the fabric is lowered. A preferred cross-sectional area ratio is 1.5 or less.
In the present invention, the fineness variation value U% measured by the normal method needs to be 1.2% or less. When the fineness fluctuation value U% exceeds 1.2%, when the woven fabric is used, surface irregularities are conspicuous and become a quality defect.

In the present invention, in the fineness variation U% chart measured by the inert method, it is necessary that the difference between the decitex of the peak and valley of the waveform continuous in the yarn length direction is 8% or less. If the difference in decitex between peaks and troughs continuous in the yarn length direction is larger than 8%, when the woven fabric is used, the portion becomes band-like spots, which is a quality defect.
Moreover, it is preferable that the CV value in the period of 30-80 m by a fineness fluctuation | variation frequency analysis is 0.5 or less. When the CV value is larger than 0.5, band-like spots may be formed in the woven fabric.
FIG. 1 shows a chart of a conventional composite yarn in which fineness variation occurs in the yarn length direction measured in the inert mode. FIG. 2 shows a chart of the composite yarn of the present invention in which the fineness variation is eliminated by the same measurement. As shown in FIG. 2, band-shaped dye spots and streak-like defects are not generated on a woven fabric for the first time by using a PTT composite yarn in which fineness variation measured in an inert mode over a long yarn length is eliminated. The fabric quality can be improved.

In the present invention, it is preferable that the composite yarn before boiling water treatment has a spiral crimp. If the composite yarn before boiling water treatment is a random crimp without a spiral crimp, when it is made into a woven fabric, the smoothness of the surface is reduced and it becomes thick, and the quality is inferior. Prone.
The PTT composite yarn of the present invention preferably has a dry heat shrinkage stress value of 0.15 to 0.35 cN / dtex. When the dry heat shrinkage stress value is less than 0.15 cN / dtex, sufficient stretch is difficult to develop when a woven fabric is used. On the other hand, if it exceeds 0.35 cN / dtex, the surface quality of the fabric may be rough. More preferably, it is 0.25 to 0.33 cN / dtex.
In the PTT composite yarn of the present invention, the temperature at which the dry heat shrinkage stress value is maximum is preferably 160 to 210 ° C. When the temperature at which the dry heat shrinkage stress value is maximum is less than 160 ° C., when the woven fabric is used, shrinkage due to crimping may occur during storage of the raw machine, resulting in poor quality. Further, it is difficult to produce a product having a temperature higher than 210 ° C. More preferably, it is 160-190 degreeC.

The PTT composite yarn of the present invention preferably has a breaking elongation of 25 to 40%. When the elongation at break is less than 25%, stretch breakage occurs and industrially stable production becomes difficult. If the breaking elongation exceeds 40%, the breaking strength becomes about 2 cN / dtex or less, and the tear strength of the fabric is lowered. A more preferable elongation at break is 25 to 35%.
The fineness and single yarn fineness of the PTT composite yarn of the present invention are not particularly limited, but a fineness of 20 to 300 dtex and a single yarn fineness of 0.5 to 20 dtex are used.
The single yarn cross-sectional shape is not particularly limited, and may be a round, Y, W-shaped atypical cross-section, a hollow cross-sectional shape, or the like.
The PTT composite yarn of the present invention has a matting agent such as titanium oxide, a heat stabilizer, an antioxidant, an antistatic agent, an ultraviolet absorber, an antibacterial agent, various pigments, etc. within a range that does not interfere with the effects of the present invention. These additives may be contained or copolymerized.

The production method according to the second invention of the present invention will be described below.
In the production method of the present invention, it is necessary to perform melt spinning at a difference in intrinsic viscosity between two polyester components of 0.2 to 0.9 dl / g.
If the difference in intrinsic viscosity is less than 0.2, sufficient stretchability and recoverability cannot be obtained when a woven fabric is used. In addition, if the difference in intrinsic viscosity exceeds 0.9 dl / g, even if the spout design and discharge conditions are changed, yarn bending and hole contamination during discharge cannot be sufficiently eliminated, and the fineness variation of the PTT composite yarn may not be eliminated. It becomes large and is not preferable. A preferable intrinsic viscosity difference is 0.2 to 0.8 dl / g. When both components are PTT, the intrinsic viscosity difference is preferably 0.2 to 0.4 dl / g.
In the production method of the present invention, it is necessary that the heat retaining area from the spinneret surface to the start of cooling be 50 to 150 mm. When the heat retaining area is shorter than 50 mm, U% becomes larger than 1.2 and the breaking strength decreases. If the heat retention region is longer than 150 mm, the height difference of the U% waveform becomes larger than 8%. A preferable length of the heat retaining region is 70 to 130 mm.

In the production method of the present invention, the nozzle discharge linear velocity needs to be 4 to 9 m / min. When the linear velocity is 4 m / min or less, the waveform of U% increases, and the difference between the peaks and valleys of the continuous waveform exceeds 8%. Further, when the linear velocity is higher than 9 m / min, the yarn bending becomes large and the periphery of the spinning hole becomes dirty, so that stable spinning cannot be performed. A preferable discharge linear velocity range is 4 to 8 m / min.
In the production method of the present invention, it is necessary that the change in the wind speed time of the cooling air is 0.05 m / second or less. When the wind speed time change is larger than 0.05 m / sec, U% deteriorates and U% becomes larger than 1.2% or the difference between the peaks and valleys of the continuous waveform becomes larger than 8%.
In the manufacturing method of the present invention, the cooling air variation in the vertical and horizontal directions of the cooling air blowing plate needs to be 0.05 m / second or less. When the cooling air speed variation is larger than 0.05 m / sec, U% is deteriorated and U% is larger than 1.2% or the difference between the peaks and valleys of the continuous waveform is larger than 8%.
Methods for reducing the time variation of the cooling air and the variation of the blowing surface include increasing the pressure loss of the cooling air blowing plate, reducing the area of the cooling air blowing plate, and making the cooling air feed pressure constant.
In the production method of the present invention, the distance from the cooling air blowing surface to the fiber needs to be 1 to 60 mm. If the distance from the cooling air blowing surface to the fiber is less than 1 mm, the yarn hits the blowing surface and breaks the yarn. On the other hand, if it is larger than 60 mm from the blow-out surface, the cooling becomes non-uniform and U% is deteriorated. A preferable distance from the cooling air blowing surface to the fiber is 1 to 50 mm. As a method of adjusting the distance from the cooling air blowing surface to the fiber, a rectifying box having several layers of slits and having a cooling air rectifying effect can be installed in front of the cooling air blowing plate.

In the production method of the present invention, the converging position of the yarn discharged from the spinning nozzle needs to be 50 to 200 cm from the spinning surface. If the converging position is less than 50 cm, the yarn is not sufficiently solidified, so that fusion or yarn breakage occurs. On the other hand, if it is larger than 200 cm, the yarn swings violently, resulting in U% defects and yarn breakage. A preferred focusing position is 80 to 160 cm from the spinneret surface.
The discharge holes of the spinneret used for the production of the present invention preferably have an inclination of 20 to 60 degrees with respect to the vertical direction. The inclination angle of the discharge hole with respect to the vertical direction refers to θ (degrees) in FIG.
The fact that the holes are inclined with respect to the vertical direction is an important requirement for eliminating yarn bending due to a difference in melt viscosity when discharging two kinds of polyesters having different compositions or intrinsic viscosities.
If the discharge hole does not have an inclination, for example, the so-called bending phenomenon in which the filament immediately after discharge bends in the direction of higher intrinsic viscosity as the difference in intrinsic viscosity increases due to the combination of PTTs, and stable spinning is performed. It becomes difficult.

In FIG. 4, it is preferable to supply and discharge a PTT polymer having a high intrinsic viscosity to the A side and another polyester or PTT polymer having a low intrinsic viscosity to the B side. For example, when the intrinsic viscosity difference between PTT polymers is about 0.2 or more, in order to eliminate bending and realize stable spinning, it is preferable that the discharge holes are inclined at least 20 degrees with respect to the vertical direction. . When expanding the intrinsic viscosity difference, it is preferable to further increase the inclination angle. However, if the inclination angle exceeds 60 degrees, the discharge part becomes elliptical and stable spinning becomes difficult. Also, the hole itself is difficult to manufacture.
A more preferable inclination angle is 30 to 50 degrees.

In the production method of the present invention, after spinning and cooling, either a two-stage spinning method in which an undrawn yarn is once wound and drawn in a separate step, or a continuous spinning drawing method in which spinning and drawing are continuously performed may be used.
In the production method of the present invention, when the continuous spinning drawing method is used, it is preferable to wind at a winding speed of 4000 m / min or less.
When the winding speed exceeds 4000 m / min, the package after winding shrinks with time, periodic spots due to the end of the package may occur, and the quality of the fabric may deteriorate. A more preferable winding speed is 2500 to 3800 m / min.
In the production method of the present invention, it is preferable to spin at a spinning speed of 1000 to 3000 m / min, heat treatment after drawing. If the spinning speed is less than 1000 m / min, the dyeing quality of the fabric may be lowered. When the spinning speed exceeds 3000 m / min, the breaking strength of the PTT composite yarn after drawing becomes about 2 cN / dtex or less, which may limit the development in fields where strength is required and increase yarn breakage. . A more preferable spinning speed is 1000 to 2600 m / min.

The production method of the present invention can be produced using a complex spinning facility having a known twin-screw extruder except for the spinneret and drawing conditions described below.
5 and 6 are schematic views of the composite spinning equipment used in the production method of the present invention.
First, PTT pellets, one component of which has been dried with a dryer 1 to a moisture content of 20 ppm or less, are supplied to an extruder 2 set at a temperature of 250 to 260 ° C. and melted. The other component is similarly melted by the dryer 3 and the extruder 4.
The molten PTT is then fed through the bends 5 and 6 to the spin head 7 set at 250 to 275 ° C., and separately metered with a gear pump. Thereafter, the two components are combined at the spinneret 9 having a plurality of holes attached to the spin pack 8 and bonded side-by-side, and then extruded as a yarn 10 into the spinning chamber.

After passing through the non-air blowing region 11 provided immediately below the spinning nozzle, the PTT yarn 10 extruded into the spinning chamber is cooled to room temperature by the cooling air 12 and solidified, and by take-up godet rolls 13 and 14 that rotate at a predetermined speed. The undrawn yarn package 15 having a predetermined fineness is wound up.
Before the undrawn yarn 15 comes into contact with the take-up godet roll 13, a finishing agent is applied by a finishing agent applying device 16.
In the production method of the present invention, a water-based emulsion type is used as a finishing agent to be imparted to undrawn fibers.
The concentration of the aqueous emulsion of the finishing agent is 15% by weight or more, preferably 20 to 35% by weight.

In the production of undrawn yarn, it is preferable to wind at a winding speed of 3000 m / min or less. A more preferable winding speed is 1000 to 2000 m / min, and further preferably 1200 to 1800 m / min.
The undrawn yarn is then supplied to a drawing process and drawn by a drawing machine as shown in FIG. Before supplying to the drawing process, it is preferable that the storage environment for the undrawn yarn is maintained at an atmospheric temperature of 10 to 25 ° C. and a relative humidity of 75 to 100%.
The unstretched fiber on the stretching machine is preferably maintained at this temperature and humidity throughout the stretching.

On the drawing machine, first, the undrawn yarn package 15 is heated on the supply roll 17 set to 45 to 65 ° C., and drawn to a predetermined fineness using the peripheral speed ratio between the supply roll 17 and the drawing roll 20. The The fiber travels while in contact with the hot plate 19 set at 100 to 180 ° C. after stretching or during stretching, and is subjected to tension heat treatment. The fiber that has exited the drawing roll is wound as a drawn yarn pann 22 while being twisted by a spindle.
More preferably, supply roll temperature is 50-60 degreeC, More preferably, it is 52-58 degreeC.
In the present invention, if necessary, a stretching pin 18 may be provided between the stretching roll 17 and the hot plate 19 to perform stretching.
The drawn yarn that has exited the drawing roll 19 is wound around the drawn yarn pann 22 while forming a balloon by the traveler guide 21.

A schematic view of a spinneret used in the production method of the present invention is shown in FIG.
In FIG. 4, (a) is a distributor plate, (b) is a spinneret, and A and B polytrimethylene terephthalates having different intrinsic viscosities are supplied from the distributor plate (a) to the nozzle (b). It is preferable that the yarn discharged from the spinning nozzle passes through a non-air blowing region of 100 to 250 mm, and is then solidified to room temperature with cooling air and once wound as an undrawn yarn. By providing this non-air blowing region, the pre-orientation of the high intrinsic viscosity component is suppressed and high strength can be obtained.
In the present invention, it is preferable that the draw stress of the composite yarn is 0.10 to 0.25 cN / dtex. If the drawing stress is less than 0.15 cN / dtex, the yarn running between the supply and drawing rolls becomes unstable, and the value of U% may not fall within the scope of the present invention. On the other hand, if it is larger than 0.25 cN / dtex, yarn breakage during stretching tends to occur. A more preferable range is 0.15 to 0.25 cN / dtex.

In the present invention, in order to impart twist and / or entanglement to the composite yarn, for example, when a stretching machine of the system illustrated in FIG. 6 is adopted, the speed of the stretching roll 19 and the rotation speed of the stretching pann 22 are determined. It can be set by the ratio. In addition, a known entanglement imparting facility can be installed at the lower part of the drawing roll 19 to impart entanglement.
When the composite yarn after drawing is wound into a panic shape, the ballooning tension is preferably 0.03 to 0.15 cN / dtex. Ballooning tension is a preferable requirement for stably maintaining the crimp characteristics of the manifest crimped composite yarn over a long period of storage. When the ballooning tension exceeds 0.15 cN / dtex, the Pann hardness exceeds 90, and the apparent crimpability may be deteriorated by long-term storage. If the ballooning tension is less than 0.03 cN / dtex, the Pann hardness is less than 80, and troubles such as collapse of the Pann shape may occur during transportation. A preferable ballooning tension is 0.05 to 0.10 cN / dtex.

  In the present invention, it is preferable to carry out so-called spinning-stretching in two stages, which is discharged from the spinneret, once cooled and solidified, wound up as unstretched, and then stretched. When storing the undrawn yarn, it is preferable to pay attention to the moisture content of the undrawn yarn and the storage temperature. When the moisture content of the undrawn yarn is high or the storage temperature is high, the fineness periodically varies due to the end face of the undrawn yarn package, and the fineness variation value U% may exceed 1.2%. The unstretched water content is 2% by weight or less, preferably 1% by weight or less. The storage temperature is 25 ° C. or lower, preferably 22 ° C. or lower.

In the production method of the present invention, a direct spinning drawing method in which spinning and drawing are continuously performed may be employed as long as the object of the invention is not impaired. Moreover, when winding up to a cheese-like package, it is preferable to make winding tension into 0.03-0.15 cN / dtex.
When the PTT composite yarn of the present invention is used for a woven fabric, it may be left untwisted or may be entangled or twisted for the purpose of improving convergence. In the case of imparting twist, the twist coefficient is preferably set to 5000 or less.
The twist coefficient is expressed by the following formula.
Twist number T (times / m) = twisting coefficient k / (fineness of false twisted yarn; dtex) ^1/2

The PTT composite yarn of the present invention may be used alone or may be used in combination with other fibers to exhibit the effects of the present invention. The composite may be used as a long fiber or as a short fiber.
Examples of other fibers to be combined include other polyester fibers, synthetic fibers such as nylon, acrylic, cupra, rayon, acetate, and polyurethane elastic fibers, and natural fibers such as cotton, hemp, silk, and wool. It is not limited to. The composite may be a long fiber or a short fiber.
Or, to make a woven fabric in which composite yarn and other fibers are mixed and mixed, the mixed fiber composite yarn is interlaced, interlaced, drawn false twisted after interlaced, only one of them is false twisted, and then interlaced It can be produced by various fiber blending methods such as mixed fiber, interlaced mixed fiber after false twisting, or interlace mixed fiber after Taslan processing, Taslan processing after interlaced fiber mixing, Taslan mixed fiber, etc. The mixed fiber composite yarn obtained by such a method is preferably provided with an entanglement degree of 10 pieces / m or more, preferably 15 to 50 pieces / m.

The present invention will be described in more detail with reference to the following examples, but it goes without saying that the present invention is not limited to these examples.
In addition, the measurement method and measurement conditions of the physical property performed in the Example are demonstrated.
(1) Intrinsic viscosity Intrinsic viscosity [η] is a value determined based on the definition of the following equation.
[Η] = lim (ηr−1) / C
C → 0
Ηr in the definition formula is a value obtained by dividing the viscosity at 35 ° C. of a diluted solution of a PTT polymer dissolved in an o-chlorophenol solvent having a purity of 98% or more by the viscosity of the solvent measured at the same temperature. Is defined. C is the polymer concentration expressed in g / 100 ml.

(2) Fineness Fluctuation Value U% / U% Waveform Height Difference / Fineness Fluctuation Frequency Analysis The fineness fluctuation value chart (graph; Diagram Mass) is obtained by the following method and U% is measured simultaneously.
Measuring instrument Evenes tester (Zerbegger Worcester; Wooster tester: UT-4)
Measurement conditions Measurement method Normal Thread speed 100m / min Tension setting (Tension) AUTO
Twist S10000rpm
Measuring thread length 2000m
Scale ± 10.0%
・ Fineness fluctuation value U%
The fluctuation chart and displayed fluctuation values were read directly.
・ U% waveform height difference Measure under the same conditions as above except that the measurement method is inert and the yarn length is 2000 m, and take a chart. Then, the largest one is read by the height difference between the peaks and valleys that are continuous in the yarn length direction.
・ Fineness fluctuation frequency analysis Using the fineness fluctuation frequency analysis software attached to the Evestester, measure 2000 m under the above conditions and read the period and CV value.

(3) Cooling air speed time fluctuation The central part of the cooling air blowing plate is measured with an anemometer Crimomaster 6543 (manufactured by Nippon Kanomax) for 5 minutes, and a chart is written. The maximum and minimum wind speeds during this period are read, and the difference is taken as the cooling wind speed time variation.
(4) Vertical and horizontal variations in the cooling air blowing surface An anemometer CLIMO MASTER 6543 (manufactured by Nippon Canomax) with a cooling wind speed of 50 cm from the top of the cooling air blowing plate, the width of the spinneret plus 5 cm in the left and right in steps of 2 cm. The difference between the maximum and minimum cooling air speeds is taken as variation.
(5) Distance from cooling air blowing surface to fiber A single yarn in a multifilament farthest from the blowing plate is measured at a distance from the cooling air blowing surface to the fiber at 200 mm below the spinning surface.

(6) Dry heat shrinkage stress value It measured using the thermal-stress measuring apparatus (Kanebo engineering company make, brand name KE-2).
A fiber is cut into a length of about 20 cm, both ends of the fiber are tied, a ring is formed, and the measuring instrument is loaded. Measurement is performed under conditions of an initial load of 0.05 cN / dtex and a heating rate of 100 ° C./min, and the temperature change of the thermal stress is written on the chart. The heat shrink stress draws a mountain-shaped curve at high temperatures. A value obtained by the following formula from the read value (cN) of this peak value was defined as a dry heat shrinkage stress value.
Dry heat shrinkage stress value (cN / dtex) =
(Reading value of peak value cN) / (dtex × 2) −initial load (cN / dtex)

(7) Dry heat 90 ° C. expansion / contraction rate The yarn was scraped 10 times with a measuring machine having a circumference of 1.125 m, and a load of 8.8 × 10 ⁻³ cN / dtex was applied, and the temperature was set to 90 ° C. Heat treat in oven for 15 minutes. After the treatment, it was left still for a whole day and night in a constant temperature and humidity room defined in JIS-L-1013. Next, the skein length is measured by applying the load shown below to the skein, and the stretch / elongation rate is measured from the following formula.
Dry heat 90 ° C. stretching elongation% (DCE ₁₀₎ = [(L2-L1) / L1] × 100
However, L1 = 2 × 10 ⁻³ cN / dtex load skein length
L2 = 0.09 cN / dtex load with load applied

(8) Actual crimping rate The yarn was scraped 10 times with a measuring machine having a circumference of 1.125 m, and left free in a constant temperature and humidity chamber defined in JIS-L-1013. Next, the skein length is measured by applying the following load to the skein, and the actual crimp rate is measured from the following formula.
Realized crimp rate = [(L2-L1) / L2] × 100
However, L1 = 2 × 10 ⁻³ cN / dtex load skein length
L2 = 0.18 cN / dtex Load-added skein length (9) Form of crimp The yarn is squeezed 10 times with a measuring machine having a circumference of 1.125 m and heat-treated in boiling water for 30 minutes with no load. Then, after air drying, the form of crimps is observed with a microscope at a magnification of 150 times.

(10) Spinning stability Unstretched yarn was spun for 2 days with a melt spinning machine equipped with an 8-end spout per spindle, and then stretched using a twisting machine, and yarn breakage was confirmed for each example. did.
From the number of occurrences of yarn breakage during this period and the occurrence frequency of fluff existing in the obtained composite yarn pirn (ratio of the number of fluff pirns), the determination was made as follows.
◎; Thread breakage 0 times, Fluff generation pann ratio 5% or less ○; Thread breakage 2 times or less, fluff generation pann ratio less than 10% ×; Thread breakage 3 times or more, Fluff generation pann ratio 10% or more

(11) Quality evaluation of woven fabric Fabric preparation was performed as follows.
A plain woven fabric was prepared using the 56 dtex / 24f composite yarn of each of the examples and comparative examples of the present invention as the warp and the 84 dtex / 36 f PTT single component yarn of Solotex Co., Ltd. as the weft.
Warp density 110 / 2.54cm
Weft density 98 / 2.54cm
Water jet loom ZW-303 manufactured by Loom Tsudakoma
Weaving speed: 450 rotations / minute The obtained raw machine was continuously scoured at 95 ° C. with an open soaper and then cylinder dried at 120 ° C., followed by dyeing at 120 ° C. with a liquid dyeing machine. Next, a series of finishing and width setting heat treatment was performed at 175 ° C.
The obtained woven fabric was inspected by a skilled inspection engineer, and the dyeing quality was determined as follows.
◎: Very good, without defects such as warp streaks, spots ○: Good, without faults such as streaks, spots, etc.

[Examples 1 to 4, Comparative Examples 1 to 6]
In the present embodiment, the effects of the length of the heat retaining region from the spinning surface to the start of cooling, the time variation of the cooling air speed, and the variation of the cooling air speed of the cooling air blowing plate will be described.
As shown in Table 1, PTT having an intrinsic viscosity of 1.3 containing 0.4% by weight of titanium oxide as shown in Table 1, and PTT pellets having an intrinsic viscosity of 0.9 containing 0.4% by weight of titanium oxide as the other component A 56 dtex / 24 filament PTT composite yarn pan was produced using a spinning machine and a twisting machine as shown in FIGS.
The spinning conditions in this example are as follows.
(Spinning conditions)
Pellet drying temperature and water content reached 120 ° C, 15ppm
Extruder temperature A-axis 250 ° C
B-axis 250 ° C (PTT)
290 ° C (PET)
Spin head temperature 265 ° C (PTT / PTT composite)
275 ° C (PTT / PET composite)
Polymer discharge rate Set for each condition so that the fineness of the drawn yarn is 56 dtex.
Cooling air condition Temperature 22 ℃, relative humidity 90%
Speed 0.4m / sec
Finishing agent Water-based emulsion based on polyether ester: 20% by weight
Take-off speed 1500m / min

(Undrawn yarn)
Fineness Set so that the fineness after stretching is 56 dtex Moisture content 0.5 wt%
Storage temperature 22 ℃
(Extension conditions)
Stretching speed 800m / min Spindle speed 8000 times / min Stretching roll temperature 58 ° C
Hot plate temperature 140 ° C
Interlace pressure Set pressure according to the degree of entanglement Ballooning tension 0.07 cN / dtex
(Drawn yarn pirn)
Fineness / filament 56dtex / 24f
Winding amount 2.5kg
Twist 20 times / m
Pahn hardness 84

As is apparent from Table 1, if the length of the heat retaining region, the time variation of the cooling air speed, the cooling air variation of the cooling air blowing plate, and the distance from the cooling air blowing surface to the fiber are within the scope of the present invention, the obtained fiber Satisfies the requirements of the present application, and the fabric using it as a warp has good quality.

[Examples 5-6, Comparative Examples 7-8]
In this example, the effect of the discharge linear velocity of the PTT composite yarn and the U% of the fiber will be described.
The composite yarn was wound up under the conditions of Example 1 while changing the diameter of the nozzle hole. Table 2 shows the physical properties of the obtained composite yarn and fabric. As is apparent from Table 2, if the discharge linear velocity is within the range of the present invention, good U% and fabric quality are exhibited.

[Examples 7 to 9, Comparative Examples 9 to 10]
In this example, the effect of the intrinsic viscosity difference of the polymer will be described.
The polymer and the intrinsic viscosity were changed under the conditions of Example 1, and the composite yarn was wound up. Table 3 shows the physical properties of the obtained composite yarn and fabric. As is apparent from Table 3, when the polymer intrinsic viscosity difference is within the range of the present invention and the physical properties are within the range of the present invention, the fiber has good spinnability and fabric stretch performance.

[Examples 10-11, Comparative Examples 11-12]
In this embodiment, the effect of the single yarn cross-sectional shape will be described.
Under the conditions of Example 1, the spinneret shape was changed and the composite yarn was wound up. Table 4 shows the physical properties of the obtained composite yarn and fabric. As is apparent from Table 4, Examples 10 to 11 in which the cross-sectional shape of the single yarn is within the scope of the present invention show good fabric quality, but the cross-sectional area ratio spun by the spinneret in which two kinds of pore sizes are mixed is shown. Comparative Example 11 greater than 2 and Comparative Example 12 having a flatness spun in the shape of a spout hole in which two circles were joined had a poor fabric quality.

[Example 12, Comparative Examples 13-14]
In this embodiment, the effect of the distance from the spinneret to the focusing position will be described.
The distance of the focusing position was changed under the conditions of Example 1, and the composite yarn was wound up. Table 5 shows the physical properties of the obtained composite yarn and fabric. As is apparent from Table 5, Example 12 in which the distance of the converging position is within the scope of the present invention shows good spinnability, but Comparative Examples 13 to 14 outside the scope of the present invention have many yarn breaks, U% also showed a bad value.

  It is preferably used as a yarn for a knitted fabric, particularly a stretch knitted fabric to which stretch performance is imparted.

An example of the U% chart measured by the inert method is shown. (Bad example outside the scope of the present invention) An example of the U% chart measured by the inert method is shown. (Example of the present invention) An example of a chart that has been subjected to frequency analysis by the Evenes Tester is shown. It is the schematic which shows an example of the discharge hole used when spinning the composite yarn of this invention. It is the schematic which shows an example of the spinning equipment which manufactures the composite yarn of this invention. It is the schematic which shows an example of the twisting equipment which manufactures the composite yarn of this invention.

Explanation of symbols

1: Polymer chip dryer 2: Extruder 3: Polymer chip dryer 4: Extruder 5: Bend 6: Bend 7: Spin head 8: Spin pack 9: Spinneret 10: Multifilament 11: Insulating region 12: Cooling air 13: Finishing agent application device 14: First godet roll 15: Unstretched package 16: Finishing agent application device 17: Supply roll 18: Stretching pin 19: Hot plate 20: Stretching roll 21: Traveler guide 22: Stretching pan

Claims (7)

It consists of a single yarn group in which two polyester components are bonded to a side-by-side type or an eccentric sheath core type, and at least one component constituting the single yarn is polytrimethylene terephthalate, and the following (1) to (6 The polytrimethylene terephthalate composite yarn characterized by satisfying the requirements of
(1) The cross-sectional shape of the single yarn has a flatness of less than 1.2. (2) The stretch / elongation ratio (DCE ₁₀ ) after dry heat treatment at 90 ° C. under a load of 8.9 × 10 ⁻³ cN / dtex. 10% or more (3) The actual crimp rate is 15% or more (4) The maximum and minimum cross-sectional area ratio of the single yarn constituting the material is 2.0 or less (5) The fineness variation value U% measured by the normal method is 1 .2 or less (6) In the fineness fluctuation value U% chart measured by the inert method, the difference between the peaks and troughs of the continuous waveform in the yarn length direction is 8% or less with respect to the average decitex (however, the fineness fluctuation value U% Is measured over a yarn length of 2000 m) The polytrimethylene terephthalate composite yarn according to claim 1, wherein the CV value in a period of 30 to 80 m by a fineness variation frequency analysis is 0.5% or less.
(However, the fineness variation value U% is measured over a yarn length of 2000 m)   The polytrimethylene according to claim 1 or 2, wherein the dry heat shrinkage stress value is 0.15 to 0.35 cN / dtex, and the temperature at which the dry heat shrinkage stress is maximum is 160 ° C to 200 ° C. Terephthalate composite yarn.   The polytrimethylene terephthalate composite yarn according to any one of claims 1 to 3, wherein the composite yarn before boiling water treatment has a helical crimp.   5. The polytrimethylene terephthalate composite yarn according to claim 1, wherein both components constituting the single yarn are polytrimethylene terephthalate. When producing a composite yarn in which two polyester components are composed of a single yarn group bonded to a side-by-side type or an eccentric sheath core type, and at least one component constituting the single yarn is polytrimethylene terephthalate, A method for producing a polytrimethylene terephthalate composite yarn, which satisfies the requirements (A) to (G).
(A) The two polyester components melt at an intrinsic viscosity difference of 0.2 to 0.9.
(B) The polymer discharge linear velocity per discharge hole is discharged at 4 to 9 m / min.
(C) The heat insulation area | region from a spinneret surface to a cooling start shall be 50-150 mm.
(D) Change the time variation of the cooling air within 0.05 m / sec.
(E) The variation in the vertical and horizontal directions of the cooling air blowing surface is within 0.05 m / second.
(F) The distance from the cooling air blowing surface to the fiber is 1 to 60 mm.
(G) The distance from the spinning nozzle to the focusing position is 50 to 200 cm.   The method for producing a polytrimethylene terephthalate-based composite yarn according to claim 6, wherein drawing is performed so that the drawing stress is 0.1 to 0.25 cN / dtex.

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