KR20120078205A - Corrugated polyester fiber and woven knit fabric prepared therefrom - Google Patents

Abstract

PURPOSE: A polyester fiber of a wave type containing titanium oxide is provided to property and upright properties. CONSTITUTION: A polyester fiber of a wave type containing titanium oxide has characteristics of: 2% or less of fiber extension rate at initial and, 10% or less of fiber extension rate at 10% or less of fiber extension rate at 1.3g/d to 3.7g/d of stress section. The fiber contains 0.2-0.3 wt% of titanium dioxide.

Description

Corrugated Polyester Fiber and Woven Fabric Containing the Same {Corrugated Polyester Fiber and Woven Knit Fabric prepared therefrom}

FIELD OF THE INVENTION The present invention relates to corrugated polyester fibers and woven fabrics comprising the same, and more particularly to corrugated polyester fibers having a smooth luster due to soft touch due to low bending stiffness and diffuse reflection due to corrugated fiber cross sections. It's about knitting.

Woven fabrics made of polyester fibers have problems in terms of uprightness and openness after brushing. Therefore, in order to improve the uprightness and openness of fibers, a fiber binding means such as twisting yarns or interlacing is generally used. It is used.

However, in the case of polyester fiber, in order to fix the shape of the fiber structure such as the twisted form of the yarn, the form of the fiber by interlacing, etc., even after brushing and hair removal processing in the subsequent process, the fibers concentrated by dyeing or the like are opened upright. It becomes difficult to make it, and as a result, the quality of the surface of a woven fabric falls.

In order to solve this problem that polyester fibers have, it has been proposed to use polyester fibers having a flat cross section. For example, Japanese Patent Laid-Open No. 56-107044 discloses an artificial fur having a long and short pile yarn made of a flat cross-section polyester fiber. This relates to a woven fabric using polyester short fibers called sliver knits, but it cannot be said that problems specific to polyester fibers regarding weaving, knitting, raising, openness, and uprightness of post-napping fibers have been sufficiently solved.

In addition, Japanese Patent Application Laid-Open No. 63-12737 discloses a woven fabric made of a polyester fabric containing 0.2 wt% or more of titanium dioxide and including a pile yarn having a flat cross section, and limiting the length of the pile to 5 mm or less to improve the feeling of appearance. It is.

In addition, Korean Patent Publication No. 2006-0123820 discloses a double-sided polyester fiber for velvet fabric having excellent hair growth and gloss by maximizing bending elasticity while maintaining a soft gloss by making a cross-section of a constituent fiber into a dumbbell shape. However, such a technique does not sufficiently solve the problem related to the uprightness of the polyester fiber, and therefore, there is a demand for improvement.

The present invention is to solve the problems of the prior art as described above, one object of the present invention is to appropriately adjust the force-strain curve of the polyester fiber, expressing low elongation and high strength at 10% elongation, It is to provide a corrugated polyester fiber containing titanium dioxide and further excellent in excellent brushing property, uprightness of the fiber after brushing, touch and gloss.

It is still another object of the present invention to provide a knitted fabric comprising polyester fibers having excellent uprightness, brushability, feel, gloss, and the like.

One aspect of the present invention for achieving the above object is that, in a corrugated polyester fiber containing titanium dioxide, (a) less than 2% when the fiber measured in the dry state is subjected to an initial stress of 1.3 g / d (B) less than 10% elongation in the stress section from 1.3 g / d to 3.7 g / d; (c) has a force-strain curve of at least 10% until the yarn is cut from a tensile strength of 3.7 g / d, and elongation at break is 20% or less; It provides a corrugated polyester fiber characterized in that the ratio (L / W) of the length (L) and the width (W) of the cross section of the 2 to 6.

Also provided is a corrugated polyester woven fabric comprising the fibers.

The corrugated polyester fiber of one embodiment of the present invention adjusts the force-strain curve appropriately, so that the fiber has excellent uprightness and has a soft touch due to low bending stiffness. In addition, since it has a corrugated cross section, it expresses the sublime gloss due to the diffuse reflection, prevents non-reflectiveness, and has a merit that the fabric thickness is reduced compared to a simple flat shape when the fiber is overlapped due to the corrugated cross section.

Thus, the corrugated polyester fibers of the present invention can be widely used in the manufacture of garment and innerwear knitted fabrics, circular knit bores, foil fabrics, bidirectional stretch fabrics, automotive seats and warp knits.

Figure 1 shows a cross section of corrugated polyester fiber of one embodiment of the present invention.
Figure 2 is a schematic view of the manufacturing process of corrugated polyester fiber of one embodiment of the present invention.
3 is a graph showing an example of a stress-strain curve of corrugated polyester fibers according to the present invention.
4 is a graph showing an example of a force-strain curve of a conventional polyester fiber.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. In addition, in the following description of the present invention, a detailed description of related general functions or configurations will be omitted.

The present invention adjusts the force-strain curve of the fiber produced to ensure that the polyester fiber has the proper elongation and the appropriate strength at 10% elongation. The force-strain curve of corrugated polyester fibers according to the invention measured at room temperature is (a) less than 2% elongated when the fibers measured in the dry state are subjected to an initial stress of 1.3 g / d, and (b) 1.3 g less than 10% elongation in the stress range from / d to 3.7 g / d; (c) has a force-strain curve of at least 10% until the yarn is cut from a tensile strength of 3.7 g / d, and elongation at break is 20% or less, (d) the fiber has a W-shaped wave, It is characterized by the ratio L / W of the length L and the width W of the cross section of a fiber being 2-6.

Since the uprightness of the pile fiber is related to the durability of the upright fiber, the uprightness of the fiber is a very important factor in determining the quality in the knitted fabric. It is preferred that the polyester fibers according to the invention elongate less than 2% when subjected to an initial stress of 1.3 g / d in order to produce fibers with good uprightness. When the fiber is stretched by 2% or more with respect to the initial stress of 1.3 g / d, it becomes difficult to have good uprightness. In addition, the fibers of the present invention is preferably less than 10% elongation in the stress section from 1.3g / d to 3.7g / d. If it is stretched more than 10%, the fiber of the pile part cannot be uniformly cut during processing of the knitted fabric, and the quality is reduced. Moreover, it is preferable to extend | stretch 10% or more from the tensile strength of 3.7 g / d until a yarn is cut | disconnected. This is because when the elongation is less than 10%, the elongation of the fiber is excessively insufficient, which causes the fiber to tear during processing such as brushing.

The cross section of the fiber of the present invention is a waveform having a "W-shape" as shown in FIG. Corrugated fiber of the present invention has the advantage that the upright is improved because the pile can easily overcome the disadvantage that the file is easily bent in the lateral direction compared to the flat rectangular yarn. It is preferable that ratio L / W of the length L and the width W of the cross section of a pile fiber becomes 2-6. When L / W becomes less than 2, openness is bad, and when L / W exceeds 6, flexibility becomes too much and uprightness becomes bad.

It is preferable that the polyester fiber of this invention consists of a polyethylene terephthalate polymer, and contains titanium dioxide.

The polyethylene terephthalate polymer contains at least 85 mole% of ethylene terephthalate units and preferably consists only of ethylene terephthalate units. Optionally, the polyethylene terephthalate can incorporate small units derived from one or more ester-forming components other than ethylene glycol and terephthalene dicarboxylic acid or derivatives thereof as copolymer units. Examples of other ester forming components copolymerizable with polyethylene terephthalate units include glycols such as 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and the like, terephthalic acid, isophthalic acid, hexahydroterephthalic acid, stilbene di Dicarboxylic acids such as carboxylic acid, bibenzoic acid, adipic acid, sebacic acid, azelaic acid.

It is preferable to contain 0.2-4.0 weight% of content of the titanium dioxide contained in polyester fiber, and it is most preferable to contain 2.5 weight%. If the content is less than 0.2% by weight, there is a disadvantage in that the light reflection on the surface of the yarn is increased to have a bundle luster. And when the content exceeds 4.0% by weight, the deep colorability is excellent, but there is a problem that the spinning and physical properties of the fiber is lowered.

Titanium dioxide to be added can be used conventionally having a particle size of the size that can be added to the polyester fiber, it is preferably 0.6 μm or less.

In the present invention, the number average molecular weight (Mn) of the polyethylene terephthalate fiber is preferably 15,000 to 20,000, the weight average molecular weight (Mw) is 35,000 to 45,000. The polydispersity index (PDI) is preferably 1.8 to 2.6, more preferably 2.0 to 2.4. When the PDI is less than 1.8, it has a high elongation, which results in poor uprightness and poor napping, which is not preferable. If the PDI exceeds 2.6, short cutting occurs due to low elongation, and the radiation and napping are poor, which is not preferable. Therefore, it is important to adjust the PDI to this value by appropriately polymerizing the polyethylene terephthalate.

2 shows a process for producing corrugated polyester fibers of the present invention, wherein a polyester chip containing titanium dioxide and having an intrinsic viscosity in the range of 0.5 to 0.8 is melted by setting the temperature condition of the extender 1 low Let's do it.

At this time, the temperature of the molten polymer is set to 270 to 295 ° C. and the temperature is given for keeping the gear pump 2 warm. In this case, the polymer passing through the gear pump 2 is lowered by lowering the set temperature of the gear pump 2. The temperature can be adjusted to 270 ~ 295 ℃ so that pyrolysis due to exothermic or high temperature does not occur as much as possible, so as not to lose the properties of the polymer itself as much as possible.

The nozzle cross section of the spinneret (3) has four bars at regular intervals. The ratio of the length (L) and width (W) of the nozzle hole (L / W) is 2 to 6 to maintain the spinning draft at a constant level. The spinning temperature is 270 to 295 ° C. and the spinning speed is 3,500 to 4,000 m / min. The spinning yarn is cooled by the cooling wind and then oiled (4).

The oiled yarns are stretched on the first gothic roller 5 and the second gothic roller 6. The second gothic roller 6 is applied by applying a guide of a certain shape before the second gothic roller 6. The area of yarn contacting the roller surface of the upper surface is about 500 to 5,000 cm ² to keep the spread of the yarn constant. The stretched yarn is relaxed and then wound on a winder (7).

In order to obtain the force-strain curve of the polyester fiber of the present invention, it is important to control the polydispersity index of the polyethylene terephthalate fiber. Therefore, in the present invention, the polydispersity index of the fiber is adjusted so that the number average molecular weight (Mn) is 15,000 to 20,000 and the weight average molecular weight (Mw) is 35,000 to 45,000. .

In order to obtain the force-strain curve of the polyester fiber of the present invention, it is important to control the contact area between the high pitch roller and the yarn contacted during stretching. It is preferable that the contact area | region of the yarn in the 1st high vault roller 5 and the 2nd high vault roller 6 in which extending | stretching takes place is 500-5,000 cm <^2> . If the area where the oiled yarn contacts the surface of the high-tension roller where the stretching occurs is less than 500 cm ² , there is no uniform heat transfer between the threads and the nonuniformity of the oil causes the lowering of the stretchability. If the area of contact between the yarns is larger than 5,000 cm ² , problems such as pin yarn induction and tar generation due to contact between yarns occur. There are many factors that affect the area of yarn contacting the high-golt roller surface. The area of contact first increases in proportion to the number of turns of the yarn wound on the stretched high-golt roller. That is, the contact area can be adjusted by adjusting the number of windings. Another important factor is to apply a guide of a certain shape to keep the spread of the yarn between the high rollers to adjust the winding width of the high rollers. For example, a narrow groove is used for narrow guide grooves, so the width of the contact is reduced, resulting in a decrease in contact area. If the guide is flat, the contact width is increased and the contact area increases. Another factor controlling the contact area is the draw tension of the roller, the draw temperature and the amount of emulsion.

The present invention can obtain a desirable force-strain curve of the fiber by organically combining the various factors to adjust the width of the yarn in contact with the surface of the high pitch roller during stretching to 500 ~ 5,000 cm ² .

Corrugated polyester fiber produced through such a process has excellent uprightness, which is useful for the manufacture of garment and interior knitted fabrics, circular knitting boa, foil paper, two-way stretch fabric, automobile seat, warp knitted fabric, etc. Can be. In particular, the knitted fabric obtained from the polyester fiber of the present invention has a strong resistance to repeated loads, and thus can be suitably used for automobile interior materials (eg, car seats) that are subjected to human load. Moreover, in automobile interior materials, in order to provide a sense of quality, a raising process can be performed. As a raising method, the general raising method can be employ | adopted, As a raising machine, it uses the fruit of thistle, the use of a needle | bubble, the use of sandpaper, etc., Both wet or dry can be employ | adopted.

Hereinafter, the structure and effect of the present invention will be described in more detail with specific examples and comparative examples, but these examples are only intended to more clearly understand the present invention, and are not intended to limit the scope of the present invention.

The force-strain curve of the fiber of the present invention was measured by a tensile tester using the ASTM 2256 method after the fiber was left for 24 hours in a standard condition, that is, a constant temperature and humidity chamber at a temperature of 25 ° C. and a relative humidity of 65%.

[Examples 1 to 3]

A polyethylene terephthalate chip containing titanium dioxide and having an intrinsic viscosity of 0.65 was extruded through a nozzle having four bars having a width of 0.6 mm and a ratio of length and width (L / W) of three. The spun yarn was cooled with air at 15 ° C., concentrated, oiled, and stretched by passing a guide having a width of 4 mm in a flat groove formed between the first and second high vane rollers. The stretched man was wound up in the winder. Other spinning conditions are shown in Table 1, and the physical properties of the prepared fiber are shown in Table 2 below.

[Comparative Examples 1 to 3]

A corrugated polyester fiber was produced in the same manner as in Example 1-3 except that the guide form before the second roller was a wide flat form and the width of the guide groove was 6.5 mm. At this time, the other spinning conditions were carried out as shown in Table 1, measured by the physical properties of the resulting polyester polyester fibers are shown in Table 2 together.

3 and 4 show the table obtained by measuring the yarn obtained in the Examples and Comparative Examples through a fiber tensile tester.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Titanium Dioxide Content (wt%) 2.5 2.0 1.9 2.5 2.0 2.0 PET Fiber Mn 18,260 17,900 18,500 9,000 14,000 22,000 PET Fiber Mw 40,680 39,900 41,440 15,600 21,550 63,800 Molten Polymer Temperature (℃) 290 285 280 285 310 310 Gear pump
Polymer temperature (℃) 295 290 287 285 315 315 Cooling air pressure (mmAq) 90/100 110/120 110/120 50/60 130/140 130/140 High bolt roller contact area (mm ² ) 1,000 3,000 5,000 11,000 7,000 200 Elongation ratio 2.3 2.6 2.0 3.5 1.8 1.6 Denier Spec 75D / 36F 75D / 36F 75D / 36F 75D / 36F 75D / 36F 75D / 36F

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 PDI of the fiber 2.228 2.229 2.234 1.7 1.5 2.9 Elongation at Break of Fiber (%) 20 19.8 19.9 13.3 32.5 35.9

[Property evaluation method]

(1) Breaking elongation of processed yarn: Measure the elongated length when cutting by pulling at the speed of 200mm / min.

Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the scope of the present invention, and such modifications and variations are also within the protection scope of the present invention. Should be.

1: extruder, 2: gear pump,
3: spinnery, 4: oiling mechanism
5: first gothic roller, 6: second gothic roller
7: winder

Claims (7)

In the corrugated polyester fiber containing titanium dioxide,
(a) the fiber measured in the dry state stretches less than 2% when subjected to an initial stress of 1.3 g / d, and (b) stretches less than 10% in the stress section from 1.3 g / d to 3.7 g / d; (c) has a force-strain curve of elongation of at least 10% from a tensile strength of 3.7 g / d until the yarn is cut and an elongation at break of not more than 20%,
(d) The corrugated polyester fiber, characterized in that the fiber has a W-shaped waveform, and the ratio (L / W) of the length (L) and the width (W) of the cross section of the pile fiber is 2 to 6.
The corrugated polyester fiber according to claim 1, wherein the titanium dioxide is contained in an amount of 0.2 to 4.0% by weight based on the weight of the fiber.
The corrugated polyester fiber according to claim 2, wherein the titanium dioxide is 2.5% by weight based on the weight of the yarn.
The method of claim 1, wherein the number average molecular weight (Mn) of the fiber is 15,000 ~ 20,000, the weight average molecular weight (Mw) is 35,000 ~ 45,000, the polydispersity index (PDI) is characterized in that the waveform polyester, characterized in that 1.8 to 2.6 fiber.
5. Knitted fabric comprising the corrugated polyester fiber of any one of claims 1-4.
The woven fabric according to claim 5, wherein the woven fabric is brushed.
Automobile interior material consisting of the knitted fabric of claim 5.

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