JPH07216643A - Polyester-based yarn for woven fabric - Google Patents

Abstract

PURPOSE:To obtain a polyester-based yarn for woven fabric capable of providing the same handle as that of filament woven fabric obtained by conventional separated spinning and drawing method under the same processing condition in spite of the polyester-based yarn prepared by direct spinning and drawing method. CONSTITUTION:This polyester-based yarn is obtained by subjecting an ethylene terephthalate-based polyester to melt spinning, taking up the spun yarn by a take-off roller, without winding once, subjecting to any means of at least drawing and heat treatment and then winding. The polyester-based yarn for woven fabric has <=0.65 intrinsic viscosity, >=0.35g/d peak of thermal shrinkage stress, characteristics of >=50cm<2> large area encircled by the thermal shrinkage stress curve, <=12% shrinkage percentage in boiling water and >=6% thermal shrinkage property (SSH16).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyester fiber,
Particularly, it relates to a polyester fiber having a high heat shrinkage stress.

More specifically, polyester fibers obtained by the spinning direct drawing method (spin draw: SPD), but having the same processing conditions as those of the long fiber woven fabric using the fibers obtained by the conventional drawing for each spinning The present invention relates to a polyester fiber for a woven fabric capable of obtaining a texture.

[0003]

2. Description of the Related Art Polyester fibers have been widely used in addition to clothing applications by taking advantage of their characteristics. Especially, supported by the recent new synthetic fiber boom, the production volume is still increasing. On the other hand, in order to improve productivity, labor saving due to labor shortage, and automation, the two-step method of conventional spinning and drawing has been actively changed to a production method of drawing without winding once after spinning. There is. (Spin Draw Method) This method has been expanded not only to the field of industrial materials such as fish nets including rubber reinforcing fibers, sewing threads, ropes and hoses, but also to the field of clothing. On the other hand, the direct spinning and drawing method is aimed at improving the productivity, and therefore the final winding speed has recently reached a high speed of 6000 m / min or more.

[0004]

However, as the speed is increased, problems such as securing the heat setting time and increasing the difficulty of the winding technique occur, and if the conventionally known winding conditions are adopted as they are, it is particularly The problem that the quality difference is larger than that of the yarn (pan yarn) obtained in the two spinning and drawing processes of 1) occurs in the subsequent process. For example, when it is used as a warp yarn, the bulge of the product is insufficient as compared with the pun yarn, and there is a difference in texture such that only a thin woven fabric having a poor hand-held feeling is finished. This invention solves the above-mentioned problem of deterioration of yarn quality due to speeding up, and a unique method obtained by a production method in which a polyester continuous fiber woven fabric having an excellent texture is stretched after spinning without being wound once. The contraction stress yarn is provided.

[0005]

Means for Solving the Problems As a result of diligent studies on the difference between the characteristics of the raw yarn and the texture, the present inventors have found that the difference in the shrinkage characteristics of the raw yarn is the main cause of the difference in the texture. Even if the obtained fiber is a fiber having a specific structure and a specific shrinkage behavior, a long-fiber woven fabric having the same texture under the same processing conditions as the fiber obtained in the conventional two steps is obtained. The inventors have found that they can be obtained and have reached the present invention.

Means for solving the above problem, that is, the present invention, melt-spins a polyester whose main repeating unit is ethylene terephthalate, and after the spun yarn is taken up by a take-up roller, it is not wound once. At least stretch,
A polyester fiber for a woven fabric, which is a polyester fiber wound through any means of heat treatment and which satisfies the following properties (1) to (5). (1) Intrinsic viscosity of fiber [η] 0.65 or less (2) Peak stress (σmax) of heat shrinkage stress of fiber
35 g / d or more (3) Area enclosed by heat shrinkage stress curve 50 cm ² or more (4) Fiber boiling water shrinkage (SHW) 12% or less (5) Fiber heat shrinkage characteristic value (SSH16) 6% or more

Here, the area enclosed by the heat shrinkage stress curve refers to FIG. 3 described later which is surrounded by the curve excluding the initial load in the temperature-thermal stress curve, and the chart speed is 10 ° C./cm on the horizontal axis. The vertical axis represents the area (cm ² ) when drawn on the chart at 0.1 g / d / cm. The heat shrinkage characteristic value SSH16 is 85 ° C. × 4 when the fiber has a constant length.
The dry heat shrinkage ratio at 160 ° C. after the heat treatment for 0 minutes is shown. The dry heat shrinkage is measured according to JIS-L1013.

The polyester fiber as used in the present invention is a polyester in which at least 80% or more of all constituent units are ethylene terephthalate, and in particular polyethylene produced from terephthalic acid or its functional derivative and ethylene glycol or ethylene oxide. The main object is terephthalate, but in addition to terephthalic acid or its functional derivative as an acid component, less than 20 mol%, preferably less than 10 mol% of isophthalic acid, adipic acid, sebacic acid, azelaic acid, naphthalic acid, P- Add oxybenzoic acid, 2,5-dimethylterephthalic acid, bis (P-carboxyphenoxy) ethane, 2,6-naphthalenedicarboxylic acid, 3,5-di (carbomethoxy) benzenesulfonate or their functional derivatives. Or glycol As other diethylene glycol, propylene glycol ethylene glycol, 1,4
It may be a copolymer to which a dihydric alcohol such as butadiol or 1,4-hydroxymethylcyclohexane is added.
Further, for example, a copolymer to which an aromatic polyphosphonate for imparting flame retardancy is added may be used. In addition to these polymers antioxidants, matting agents, colorants, dyeability improvers,
Flame retardant improvers, antistatic agents, etc. may be added.

The polyester fiber of the present invention has an intrinsic viscosity [η] of 0.65 or less in order to obtain a fabric quality equivalent to or better than the yarn (pan yarn) obtained in the conventional two steps. This is good.

The polyester fiber of the present invention needs to have a peak stress σmax of heat shrinkage stress of 0.35 g / d or more. Here, when the peak stress σmax of the heat shrinkage stress is less than 0.35 g / d, it is not possible to obtain the texture due to the width-filling (also called length-fitting), which is a feature of the woven fabric. It is not preferable because it results in poor fabric.

The polyester fiber of the present invention has a heat shrinkage stress characteristic that the value of the area surrounded by the heat shrinkage stress curve is 5
It must be 0 cm ² or more. In the case where the value of the area surrounded by the heat shrinkage stress curve is less than 50 cm ² , the width of the pouch, which is a characteristic of a woven fabric, is the same as the drawback when the peak stress of the heat shrinkage stress is small. It is not preferable because it is not possible to obtain a texture due to the above, and a woven fabric having a poor hand-held feeling is obtained, and the shrinkage behavior in the subsequent process is different, so that an excellent texture cannot be obtained.

The polyester fiber of the present invention must have a boiling water shrinkage of 12% or less. Here, when the boiling water shrinkage exceeds 12%, it is not preferable because the excellent feeling equal to or higher than that of the fiber obtained in the conventional two steps aimed at by the present invention cannot be obtained.

The polyester fiber of the present invention must have a heat shrinkage characteristic value (SSH16) of 6% or more. Usually, in order to finish the woven fabric, for example, the steps of relaxing → preset → weight reduction → dying → finishing are passed, but it is necessary to control in each step in order to obtain the final length and width. This is to prevent troubles in the process such as wrinkles. The heat shrinkage characteristic value (SSH16) of the fiber is a measure for optimizing the behavior at the time of passing through the process. If this value is less than 6%, the final length and width are insufficient and the texture is poor. It is not preferable because it becomes a woven fabric.

Next, an example of the method for producing the fiber of the present invention will be described. In the production of the fiber of the present invention, first, a melted polymer is discharged from a spinneret, cooled, and solidified yarn is applied with an oil agent and taken up by a take-up roller. At this time, in order to improve migration of the oil agent after the application of the oil agent to the take-up roller, it is possible to install an interlace to which substantially no entanglement is applied. The yarn thus taken up is stretched without being wound up and heat set.
Further, the yarn temperature is cooled to the glass transition temperature or lower without relaxing the orientation of the yarn, and the tension is controlled to wind the yarn.

In order to obtain the fibers used in the woven fabric of the present invention in the yarn making process, it is important to adopt the following method. That is, since the speed at which the cooled and solidified yarn is applied with the oil agent and taken up by the take-up roller has a great influence on the heat shrinkage rate characteristic value (SSH16) of the fiber,
It is necessary to set the speed at which the heat shrinkage characteristic value (SSH16) of the fiber is 6% or more. Although not particularly limited,
The speed at which crystallization (orientation crystallization) during spinning occurs is desirable. Preferably, the take-off speed is 3500 m / mi
n or less, and more preferably 2800 m / min or less.

In order to draw this yarn, it is desirable to apply heat to the yarn before drawing, but it is not particularly limited, but it is necessary that the glass transition temperature is higher than the glass transition temperature in terms of uneven dyeing and quality. Yes, it should be set to an appropriate temperature depending on the brand, preferably between 70 ° C and 150 ° C. If the temperature is lower than 70 ° C, the stretching point is hard to be fixed, and if the temperature exceeds 150 ° C, the yarn shakes on the roller to increase the dyeing unevenness, the quality is deteriorated, and the yarn breakage increases, which is not preferable.

Next, the heated yarn is drawn and heat set. Stretching is adjusted to obtain the required high elongation
Furthermore, it is adjusted to obtain the required shrinkage behavior. In particular,
Heat setting is an important point not only in temperature but also in time, and is not particularly limited, but it is preferable to apply for 0.01 to 0.1 seconds. If the time is less than this time, the quality such as uneven dyeing is deteriorated, which is not preferable.

In order to obtain a high heat shrinkage stress, it is essential to set the yarn temperature to the glass transition point or lower without relaxing the orientation of the heat set yarn. Although not particularly limited, for example, a heating roller is further installed after the heat setting roller, the speeds of both rollers are set to be the same, and the temperature of the installation roller is set to a temperature not higher than the glass transition point. The temperature is below the glass transition point. Here, when the installation roller is not installed, or at a temperature equal to or higher than the glass transition point, it is necessary to lower the tension for winding the package in order to adjust the shape of the package. It becomes impossible to obtain fibers with high heat shrinkage stress.

[0019]

EXAMPLES The present invention is described in detail below with reference to examples.
The measured values in the evaluation of the present invention were measured by the following methods.

(Intrinsic viscosity) Measured at 30 ° C. using a mixed solution of phenol / tetrachloroethane 60/40.

(Shrinkage stress) The shrinkage stress means the highest stress value (peak stress) in the curve of temperature to shrinkage stress measured by the following measuring method, and is measured by the following measuring method. . Thermal stress measuring machine (eg SII TMA / S
S100) and a recording device linked to this are used for measurement. The materials to be measured are set in a thermal stress measuring machine with both ends sandwiched so that the total denier falls within the range of 75 to 125d and the distance between the chucks is 2 cm. An initial load of 1/30 g per denier is applied to the sample and the temperature is raised from room temperature to 300 ° C. at a heating rate of 20 ° C./min while maintaining a constant length. The stress generated at this time is recorded and the maximum stress point (peak stress) is read. The temperature at which stress starts to be generated is read as the start time.

(Area Surrounded by Thermal Shrinkage Stress Curve) The area surrounded by the thermal stress curve obtained above and the straight line of the initial load (see FIG. 3) is measured. The area is 10 ° C./cm on the horizontal axis and 0.1 g / d / cm on the vertical axis, and the area (cm
² ).

(Boiling water shrinkage ratio: SHW) JIS-L101
Measure according to 3.

(Heat Shrinkage Characteristic Value: SSH16) After heat-moisture-treating fibers at a constant length at 85 ° C. for 40 minutes, JIS-L
According to 1013, the dry heat shrinkage rate at 160 ° C. is measured.

Examples 1 to 4 and Comparative Examples 1 to 6 Polyethylene terephthalate having an intrinsic viscosity (η) of 0.635 was extruded at a spinning temperature of 285 ° C. and the finished yarn of 75d / 72f was obtained under the conditions shown in Table 1. It was Table 2 shows the physical properties of the obtained yarn. The layout of the rollers used here is shown in Fig. 1.
And shown in FIG. The number 1 in the roller layout column shown in Table 1 indicates FIG. 1, and the number 2 indicates FIG. Further, Comparative Example 6 is a yarn in which spinning and drawing are performed separately. Table 2 shows the physical properties of the obtained yarn. Further, Comparative Example 6 is a yarn in which spinning and drawing are performed separately. Table 2 shows the physical properties of the obtained yarn. Next, the obtained fiber was twisted at 3000 T / m with a twisting machine such as DT and then subjected to a twist stop set at 85 ° C. for 40 minutes to obtain a weft yarn. 75d / 60 for warp
The heterogeneous shrinkage mixed yarn of f was used as a raw material, relaxed under wet heat of 120 ° C., preset under dry heat of 190 ° C., subjected to weight loss dyeing, and then finished to obtain a woven fabric. Table 2 shows the width of the woven fabric before and after relaxation and the evaluation result of the texture after finishing.

[0026]

[Table 1]

[0027]

[Table 2]

The yarn thus obtained by the spin draw method of the present invention (SPD yarn) is usually the heating roller as the final roller for the reason of ensuring the heat setting time, and the temperature thereof is the other roller. Is set to the highest compared to. On the other hand, from the viewpoint of winding, taking into consideration the winding shape and tightening, the winding is performed with a relatively low tension. For this reason,
Normally, the winding speed is set lower than the speed of the final roller to control the tension. In effect, the final roller was subjected to relaxation, and the orientation of the amorphous portion was relaxed.

[0029]

EFFECTS OF THE INVENTION According to the present invention, a fiber having a high heat shrinkage stress can be obtained, and by controlling the shrinkage property in the post-processing step, the fiber obtained by the conventional two steps even in the spin draw system. It is possible to obtain a woven fabric having an excellent texture even under the same process conditions.

[Brief description of drawings]

FIG. 1 is a diagram showing a layout of rollers used in an example of the present invention.

FIG. 2 is a diagram showing a layout of rollers used in an example of the present invention.

FIG. 3 is a diagram showing an area surrounded by a straight line of a thermal stress curve and an initial load.

[Explanation of symbols]

1 is a nozzle, 2 is GR1, 3 is GR2, 4 is GR3, 5
Indicates the area surrounded by the thermal stress curve, and 6 indicates the fusing point.

Claims (1)

[Claims] 1. A polyester whose main repeating unit is ethylene terephthalate is melt-spun, a spun yarn is taken up by a take-up roller, and then wound by at least stretching or heat treatment without winding once. A polyester fiber for textiles, which is a taken polyester fiber and satisfies the following properties (1) to (5). (1) Intrinsic viscosity of fiber [η] 0.65 or less (2) Peak stress (σmax) of heat shrinkage stress of fiber
35 g / d or more (3) Area enclosed by heat shrinkage stress curve 50 cm ² or more (4) Fiber boiling water shrinkage (SHW) 12% or less (5) Fiber heat shrinkage characteristic value (SSH16) 6% or more