KR100939022B1 - Flat fiber of polyester - Google Patents

Abstract

The present invention relates to a fiber for a stillbirth flat polyester pile fabric containing titanium dioxide, wherein the processed yarn (a) stretches 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) elongation of at least 10% from the tensile strength of 3.7 g / d until the yarn is cut, and elongation at break is 20% The force-strain curve below gives a fiber for polyester pile fabrics having good uprightness and brushing with low elongation and high strength development at 10% elongation.

Initial stress, initial modulus, force-displacement curve, pile, uprightness, brushability, stillbirth flat yarn

Description

Flat fiber of polyester

The present invention relates to a fiber for stillbirth flat polyester pile fabric having excellent uprightness and brushing property in the manufacture of pile fabrics. Specifically, the present invention has a high strength and high modulus by appropriately adjusting the force-strain curve of the fiber. A pile fabric relates to a textile for garment and interior pile fabrics with a soft touch due to low bending stiffness and diffuse reflection due to diffuse reflection due to stillbirth flat fiber cross-section.

Conventionally, pile fabrics using polyester fibers have had problems in terms of uprightness and openness after brushing. Therefore, in order to improve fiber raising, uprightness and openness, fiber binding means such as twisting yarns or interlacing are generally used. However, in the case of polyester fibers, twisting yarns and interlacing yarns are used. In order to fix the shape of the fiber structure, such as the shape of the fiber, even after raising and hair removal treatment in the subsequent process, it is difficult to open and erect the fibers focused by dyeing or the like, resulting in deterioration of the quality of the pile fabric surface. do. 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 Application Laid-Open No. 56-107044 discloses an "artificial fur having a long and short pile yarn made of flat cross-section polyester fibers", which relates to a fabric using polyester short fibers called sliver knits. The problems specific to polyester fibers regarding the weaving, weaving, knitting, raising, openness, and uprightness of post-napping fibers could not be solved sufficiently.

In addition, Japanese Patent Laid-Open No. 63-12737, "Pile fabric made of polyester fabric containing more than 0.2% by weight of titanium dioxide and having a flat cross-section, to limit the length of the pile to 5mm or less to improve the feeling of hair." It is described. In addition, Korean Patent Publication No. 2006-0123820 discloses a "release cross-section 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 the constituent fiber". .

However, in the case of pile fabrics, the inventors have focused on the fact that the properties of the pile or the final product including the piles depend on the modulus of 10% of the fibers constituting the pile rather than the length of the pile. By providing a low elongation of the fiber and high strength at 10% elongation, it is intended to provide a fiber for a pile fabric which has an excellent expression of the quality and appearance of the bubble paper after processing, thereby increasing the uprightness of the fibers constituting the pile fabric.

The present invention seeks to provide a still produced flat polyester pile fabric fiber containing titanium dioxide, which exhibits low elongation and high strength at 10% elongation by appropriately adjusting the force-strain curve of the polyester pile fabric fiber. . In addition, the present invention provides that (a) less than 2% of the fiber measured in the dry state when subjected to an initial stress of 1.3 g / d, (b) 10% in the stress range from 1.3 g / d to 3.7 g / d It is intended to provide a fiber for a polyester pile fabric having less than 10% elongation, (c) elongation of 10% or more from a tensile strength of 3.7 g / d until the yarn is cut, and an elongation at break of 20% or less.

In addition, the present invention further aims to provide a fiber for polyester pile fabrics which is excellent in excellent brushing property, uprightness of fibers after brushing, hand and gloss, and the like.

In order to achieve the above object, the present invention provides a fiber for tetra-acid flat polyester pile fabric 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) Provide a fiber for a polyester pile fabric having 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 20% or less.

In addition, the fiber preferably contains 2.5% by weight of titanium dioxide relative to the weight of the fiber.

In addition, the fibers may have a number average molecular weight (Mn) of 15,000 to 20,000, a weight average molecular weight (Mw) of 35,000 to 45,000, and a polydispersity index (PDI) of 1.8 to 2.6.

Also provided is a stillbirth flat polyester pile fabric comprising the fibers.

The fibers for polyester pile fabrics produced according to the invention adjust the force-strain curve appropriately, which makes the fibers excellent in their upright and brushing properties and has a soft touch due to their low bending stiffness. In addition, it has a stillbirth flat cross-section, which gives a sublime luster by diffuse reflection. It is also possible to prevent shining and to reduce the thickness of the fiber compared to the simple flat shape when the fiber overlaps due to the still-flat flat cross-section, so that it is possible to manufacture the foil fabric.

Thus, the fiber for the polyester pile fabric of the present invention can be widely used in the manufacture of garment and inner pile pile fabrics, circular knitting bores, foil fabrics, bidirectional stretch fabrics, automobile seats and warp knitted fabrics.

Hereinafter, the present invention will be described in detail.

The present invention adjusts the force-strain curves of the fibers produced to ensure that the fibers for polyester pile fabrics have the proper elongation and the appropriate strength at 10% elongation. The force-strain curve of the fiber according to the invention measured at room temperature is (a) less than 2% elongated when the fiber measured in the dry state is subjected to an initial stress of 1.3 g / d, and (b) at 1.3 g / d Less than 10% in stress ranges up to 3.7 g / d, (c) from a tensile strength of 3.7 g / d to 10% or more until the yarn is cut, and an elongation at break has a force-strain curve of 20% or less It is preferable.

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 the quality of the pile fabric. It is preferred that the fiber for polyester pile fabrics 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 cut uniformly during processing of the pile fabric, and the quality is degraded. 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 the fiber elongation is excessively insufficient and the fiber breaks during processing such as raising.

It is preferable that the fiber for polyester pile fabrics 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. Alternatively, the polyethylene terephthalate may 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 and stilbenic Dicarboxylic acids such as leric 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.

The cross section of the fiber of the present invention is a tetragonal flat with four acids, as shown in FIG. The stillbirth flat fiber of the present invention has an advantage that the uprightness is improved because the pile can easily bend 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.

2 shows a process for producing the polyester fiber of the present invention, in which 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. .

At this time, the temperature of the molten polymer is set to 270 ~ 295 ℃ and the temperature is given for the warming of the gear pump (2) Even if the set temperature of the gear pump (2) is lowered and the polymer passing through the gear pump (2) The temperature can be adjusted to 270 ~ 295 ℃ so that pyrolysis due to exotherm 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 was 270 to 295 ° C. and the spinning speed was 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 high rollers (GR) 1 (5) and GR 2 (6), with a guide of some form prior to GR 2 that the yarn contacts the surface of the roller on GR 2 500 to 5,000 Make it about ² cm to keep the yarn spread. 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 generally in a range of 1.8 to 2.6 using a polyethylene terephthalate polymer having a number average molecular weight (Mn) of 15,000 to 20,000 and a weight average molecular weight (Mw) of 35,000 to 45,000. Adjust it in the way.

In order to obtain the force-strain curve of the polyester fiber of the present invention, it is important to adjust the contact area between the high-odd roller and the yarn in contact during stretching. It is preferable that the contact area of the yarns in GR 1 and GR 2 in which stretching occurs is 500 to 5,000 cm ² . If the area where oiled yarns are in contact with the surface of the GOD roller where the stretching occurs is less than 500 cm ² , there is no uniform heat transfer between the yarns and the oil non-uniformity causes deterioration of the ductility. 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 a number of factors that affect the area of yarn contacting the surface of the gond roller, and the area of contact first increases in proportion to the number of turns of the yarn wound in the stretched GR. That is, the contact area can be adjusted by adjusting the number of windings. Another important factor is the application of some form of guide to maintain a constant spread of yarns between the GRs so that the winding width of the GR can be adjusted. For example, a narrow groove is used for narrow guide grooves, so the width of contact decreases, resulting in a decrease in contact area. 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 gond roller during stretching to 500 ~ 5,000 cm ² .

The fiber for polyester pile fabric manufactured through such a process is excellent in the upright and brushing property, and thus it is suitable for clothing and interior pile fabric, circular knitting boa, foil paper, bi-directional stretching fabric, automobile seat, warp knitted fabric, etc. It can be usefully used for manufacturing.

Hereinafter, the structure of the present invention will be described in detail with specific examples and comparative examples, but these examples are only intended to 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 a ASTM 2256 method after the fiber was left in a constant temperature and humidity room at a standard condition, that is, 25 ° C. temperature and 65% relative humidity.

[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 rollers 1 and 2. The stretched man was wound up in the winder. Other spinning conditions are shown in Table 1, and the physical properties of the produced fiber are shown in Table 2.

[Comparative Examples 1 to 3]

The main conditions are the same as in Examples 1, 2, and 3, and the guide shape before the high roller 2 is a wide flat shape and the width of the guide groove is 6.5 mm. Other radiation conditions are shown in Table 1. Physical properties of the produced fiber are shown in Table 2.

TABLE 1

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 14,000 21,000 19,000 PET Fiber Mw 40,680 39,900 41,440 26,600 40,950 40,950 Molten Polymer Temperature (℃) 290 285 280 285 310 310 Polymer temperature on gear pump (° C) 295 290 287 285 315 315 Cooling air pressure (mmAq) 90/100 110/120 110/120 50/60 130/140 130/140 GR 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

TABLE 2

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 1.890 1.947 2.155 Elongation at Break of Fiber (%) 20 19.8 19.9 13.3 32.5 35.9

While the invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims. .

1 shows a cross-section of a polyester still produced flat fiber of the present invention.

Figure 2 schematically shows a manufacturing process of the polyester fiber according to the present invention.

3 is a graph showing an example of a stress-strain curve of the fiber for a polyester pile fabric according to the present invention.

4 is a graph showing an example of a force-strain curve of a fiber for a conventional polyester pile fabric.

Claims (4)

In the fiber for the stillbirth flat polyester pile fabric containing titanium dioxide, (a) less than 2% elongation of fibers measured in the dry state at 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 elongation of at least 10% from a tensile strength of 3.7 g / d until the yarn is cut, an elongation at break of not more than 20%, and 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, polydispersity index (PDI) is characterized in that the fiber for polyester pile fabrics, characterized in that 1.8 to 2.6. According to claim 1, wherein the titanium dioxide fiber for polyester pile fabrics, characterized in that contained 0.2 to 4.0% by weight relative to the weight of the fiber. delete Pile fabric containing the fiber of claim 1.

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