JP3264334B2 - Method for producing high shrinkage stress polyester fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high shrinkage stress polyester fiber by a direct spin drawing method.

[0002]

2. Description of the Related Art Polyester fibers are widely used for clothing, taking advantage of their properties. In particular, its production has been increasing, supported by the new synthetic fiber boom in recent years.

On the other hand, for the purpose of productivity, labor saving due to labor shortage, and automation, the conventional spinning and drawing two-step system is replaced with a production system in which drawing is performed without winding once after spinning. Conversion to a so-called direct spin drawing method (spin draw method) in which a drawing step is directly connected has been actively performed.

[0004] This method has been expanded not only to the field of industrial materials such as fish nets, sewing threads, ropes and hoses including rubber reinforcing fibers, but also to the field of clothing.

[0005] On the other hand, the direct spinning and drawing method aims at improving the productivity, so that the final winding speed has recently reached a high speed of 6000 m / min or more.

[0006]

However, with the increase in speed, problems such as securing the heat setting time and increasing the difficulty of the winding technique have occurred. The problem that the difference in quality is larger than that of the yarn (pan yarn) obtained in the two steps of spinning and drawing occurs in the subsequent step. For example, when used for warp yarns, there are problems in texture, such as insufficient swelling of the product as compared to pirn yarns, and finishing only in thin and poorly held fabrics. The present invention has been made to solve the above-mentioned problems of the yarn accompanying the high speed, and aims to provide a high shrinkage stress polyester fiber capable of obtaining a product having an excellent texture in a post-process. is there.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies on the difference between the yarn characteristics and the hand and found that the heat shrinkage stress of the yarn is the main cause of the difference in the hand, leading to the present invention. Was. That is, the present invention is a method for producing a polyester fiber by a direct spinning and drawing method.After the spun yarn is taken up by a take-up roller, at least drawing and winding are performed through any one of heat treatments, the final An installation roller is provided between the heating roller and the winder, the yarn is held under tension or constant tension between the final heating roller and the installation roller, and the yarn temperature at the installation roller outlet is set to a temperature equal to or lower than the glass transition point, This is a method for producing a polyester resin fiber having high shrinkage stress, wherein the polyester fiber is wound under relaxed conditions.

The polyester fiber referred to in the present invention is a polyester in which at least 80% or more of all the constituent units are ethylene terephthalate, and in particular, polyethylene produced from terephthalic acid or a functional derivative thereof and ethylene glycol or ethylene oxide. The main target is terephthalate, but in addition to terephthalic acid or a functional derivative thereof 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 -Oxybenzoic acid, 2,5-dimethylterephthalic acid, bis (P-carboxyphenoxy) ethane, 2,6-naphthalenedicarboxylic acid, 3,5-di (carbomethoxy) benzenesulfonate or a functional thereof Add derivative or glycol component To, other ethylene glycol, diethylene glycol, propylene glycol, 1,4
A copolymer to which a dihydric alcohol such as butadiol and 1,4-hydroxymethylcyclohexane is added may be used. Further, for example, a copolymer to which an aromatic polyphosphonate for imparting flame retardancy may be added. Further, an antioxidant, a matting agent, a colorant, a dyeability improver, a flame retardant improver, an antistatic agent, etc. may be added to these weights.

In the present invention, it is important to provide an installation roller between the final heating roller and the winder.

The installation roller according to the present invention includes, for example, 1
Any roller can be used as long as it is a pair of rollers, can rotate at a speed higher than the final heating roller, and can cool the yarn temperature below the glass transition point. The speed of the installation roller is not particularly limited, but is preferably in the range of 4000 m / min to 6000 m / min in order to ensure stable quality and stable productivity. The temperature of the installation roller is not particularly specified, but is preferably 70 ° C. or lower on the roller surface, in order to keep the yarn temperature below the glass transition point at the roller exit.

The heating roller referred to in the present invention may be a commonly used heating roller. The speed of the heating roller is not particularly limited, but may be 4000 m / min to 600 m / min.
The range of 0 m / min is particularly preferable for securing stable quality and stable productivity. The temperature of the heating roller is not particularly limited, but is preferably 250 ° C. or lower.

In the present invention, it is necessary that the final heating roller and the installation roller be kept under tension or constant tension. Here, if it is not held under tension or constant tension, the orientation of the amorphous portion is relaxed, and disadvantages such as a decrease in heat shrinkage stress are caused, which is not preferable.

In the present invention, it is important that the yarn is wound under a relaxed condition when the yarn temperature at the outlet of the installation roller becomes equal to or lower than the glass transition point. Here, when the yarn temperature is relaxed at a temperature equal to or higher than the glass transition point, the orientation of the amorphous portion is particularly relaxed, and the heat shrinkage stress maintained up to that point is reduced. On the other hand, if the winding is performed without relaxing, the winding becomes very hard and the shape becomes defective, and the winding cannot be removed from the winding machine.

The shrinkage stress referred to in the present invention means the highest stress value (peak stress) in a temperature-shrinkage stress curve obtained by a measuring method described later.

The shrinkage stress is measured as follows. The measurement is performed using a thermal stress measuring device (for example, TMA / SS100 manufactured by SII) and a recording device linked thereto. The specimens are aligned so that the total denier falls within the range of 75 to 125 denier, and both ends are adjusted so that the length between the chucks is 2 cm, and the sample is set in a thermal stress measuring device. The sample is subjected to an initial load of 1/30 g per denier and kept at a constant length from room temperature to
The temperature is raised to 300 ° C. at a rate of 20 ° C./min. Here, the stress generated from the sample yarn is recorded by a recorder, and the maximum stress point is read.

The present invention will be described below with reference to the drawings. FIG. 1 is a view schematically showing a direct spinning and stretching apparatus used in the present invention in one embodiment of the present invention.

In FIG. 1, 1 is a yarn, 2 is a take-up roller, 3 is a final heating roller, 4 is a take-up cheese, and 5 is an installation roller.

In FIG. 1, the yarn discharged from the nozzle and supplied with the thinned and cooled oil is heated while being taken up by the take-up roller, and is stretched between the take-up roller and the final heating roller. The drawn yarn is further heated by the final heating roller and leaves the roller while the yarn temperature remains high. In the conventional manufacturing method, tension control is performed for winding while the yarn temperature is high, and relaxation is substantially provided. On the other hand, in the present invention, for example, by installing a cooling roller as shown in FIG. 1, while the yarn temperature is high, the orientation of the amorphous portion is maintained without being substantially relaxed, and the yarn temperature is lower than the glass transition temperature. And then control the winding tension to wind up. Therefore, it is possible to maintain the orientation of the amorphous portion and obtain a packaging having a good shape. Since the orientation of the amorphous part is maintained, the resulting fiber has high heat shrinkage stress,
The feeling of the obtained product is also superior to the conventional product.

The arrangement of the rollers as shown in FIG.
For example, as disclosed in JP-A-52-85519, there is a great difference in the purpose of using the rollers. Japanese Patent Application Laid-Open No. 52-85519 discloses a method of winding a relaxed yarn at a low overfeed rate or a slight tension after stretching in order to stably wind the yarn. Heat shrinkage stress
It becomes low at the time of relaxation after drawing, and has the same physical properties as the conventional spin draw yarn.

[0020]

[Function] Yarn obtained by spin draw method (SPD yarn)
The last roller is usually a heating roller for the reason of securing a heat setting time and the like, and its temperature is set to be the highest as compared with other rollers. On the other hand, from the viewpoint of winding, winding is performed at a relatively low tension in consideration of the winding shape and winding tightening. For this reason, in a conventionally known method, the tension is controlled by making the winding speed lower than the speed of the final roller. Substantially, the orientation of the amorphous portion was relaxed by being relaxed by the final roller. According to the present invention, the relaxation of the orientation of the amorphous portion disappears,
Fibers with high heat shrinkage stress can be obtained, and products with excellent texture can be obtained.

[0021]

The present invention will be described below in detail with reference to examples.

Examples 1 to 7 and Comparative Examples 1 to 7 A pair of rollers was installed between the final heating roller and the winder, using a polyethylene terephthalate having an intrinsic viscosity [η] = 0.62, and a spinning temperature of 280 ° C. Under the conditions shown in Table 1,
A finished yarn of 5d / 36f was obtained.

As a comparative example, the yarn physical properties without an installation roller and the temperature at a hot roller temperature of 160 ° C., a hot plate temperature of 160 ° C., and a twisting speed of 1 after winding at 1500 m / min.
Table 1 shows the physical properties of the yarn drawn at 000 m / min.

[0024]

[Table 1]

[0025]

As described in the present invention, the yarn temperature is maintained substantially above the glass transition point without being relaxed before being wound from the final heating roller, and the yarn temperature is kept below the glass transition point. When the temperature reached the temperature, the yarn was relaxed, the tension was controlled, and the yarn was wound up, so that it was possible to obtain a yarn having a higher thermal stress than the yarn in the separate spinning and drawing process.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a main part of a direct spinning and drawing apparatus used in the present invention in one embodiment of the present invention.

[Explanation of symbols]

1 is a yarn, 2 is a take-up roller, 3 is a final heating roller, 4
Is a winding cheese, 5 is an installation roller, and 6 is an outlet yarn temperature measuring unit.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-134026 (JP, A) JP-A-51-123320 (JP, A) JP-A-58-220815 (JP, A) 6051 (JP, B1) (58) Field surveyed (Int. Cl. ⁷ , DB name) D01F 6/62 301-308 D02J 1/22

Claims (1)

(57) [Claims] 1. A method for producing a polyester fiber by a direct spinning and drawing method, wherein after a spun yarn is taken up by a take-up roller, it is finally heated at least when it is wound through any means of drawing or heat treatment. Provide a setting roller between the roller and the winder, hold the yarn under tension or constant tension between the final heating roller and the setting roller, set the yarn temperature at the setting roller outlet to a temperature below the glass transition point, and relax. A method for producing a high-shrinkage stress polyester fiber, wherein the polyester fiber is wound below.