TW201827661A - Hollow polyester long fiber and preparation method therefor - Google Patents

Abstract

A hollow polyester long fiber has a cross-sectional hollowness ranging from 20.0% to 45.0%, the long fiber in natural state being of a three-dimensional crimped shape, and the radius of curvature of the crimped shape being 10.0 mm-50.0 mm. The fluffily processed tows obtained by processing the hollow polyester long fiber have high fluffiness.

Description

   Polyester hollow long fiber and preparation method thereof   

The invention relates to a hollow crimped polyester long fiber and a preparation method thereof. The hollow long fiber is suitable for manufacturing long cotton for filling.

In the textile industry, feathers and downs of waterfowl, such as goose down and duck down, are usually filled in duvets, sleeping bags and various cold and warm products. The emergence of bird flu worldwide has led to a sharp decline in the production of down, which has led to price increases. At the same time, consumers also have doubts about the safety of down. Natural feathers will cause foul odor if they are not adequately washed. Therefore, it is necessary to remove the odor-causing dirt in advance to maintain the cleanliness of feathers. In addition, feather filling products such as feather quilts and feather jackets still have the problem of being difficult to wash.

To this end, the industry is committed to researching the use of synthetic fibers instead of animal down for filling. Chinese patent CN186187A discloses a short-fiber-like down-like cotton, but the short-fiber-filled cotton has a low fluffy degree, and the thermal insulation material made is grainy when touched, and the short-fiber-like down-like cotton tends to shift when washed. Therefore, it is urgent to develop a new type of filling material to replace down. Polyester fiber is easy to produce and has the advantage of low price. The development of polyester-based filling materials has a good market prospect.

An object of the present invention is to provide a polyester hollow long fiber having a three-dimensional three-dimensional crimp shape, which is suitable for manufacturing long cotton for filling and a method for preparing the polyester hollow long fiber.

The polyester hollow long fiber of the present invention has a cross-section hollowness of 20.0% to 45.0%. The polyester hollow long fiber has a three-dimensional three-dimensional crimp shape in a natural state, and the curvature radius of the crimp shape is 10.0 mm to 50.0. mm.

The polyester hollow long fiber of the present invention preferably has a monofilament fineness of 4.0 dtex to 15.0 dtex, and more preferably 5.0 dtex to 10.0 dtex.

The polyester hollow long fiber of the present invention has a three-dimensional three-dimensional crimp shape after being subjected to a dry heat treatment at 160 ° C. for 3 minutes, and the curvature radius of the crimped state is 3.5 mm to 10.0 mm.

The polyester hollow long fiber of the present invention has a polymer raw material of polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, or a modified polymer thereof.

The invention also discloses a method for preparing the above-mentioned polyester hollow long fiber. The dried chips are melt-extruded by a screw and conveyed to a metering pump through a pipe. The polymer precisely metered by the metering pump is sent to a spinning component. The spinneret of the wire assembly is a hollow spinneret, the cooling distance is 10 ~ 150mm, and the wind speed of the side blowing is 25 ~ 90m / min.

The cooling distance is preferably 60 to 110 mm; the wind speed of the side blowing is 30 to 50 m / min.

The invented polyester hollow fiber is produced by the melt spinning process. It has the advantages of simple production and low cost, and has a three-dimensional three-dimensional crimp structure. It is suitable for processing into fluffy processed yarn that can be used as filled long cotton. bundle.

FIG. 1 is a triangular hollow cross-sectional shape of a polyester hollow long fiber.

Fig. 2 is a quadrangular hollow cross-sectional shape view of a polyester hollow long fiber.

FIG. 3 is a three-dimensional three-dimensional crimp shape diagram of the polyester hollow long fiber in a natural state.

Figure 4 is a schematic diagram of the measurement of the radius of curvature.

In order to develop a filler that can replace down, the present invention provides a polyester hollow long fiber suitable for processing into a fluffy tow. Because the hollow fiber has a three-dimensional three-dimensional curly shape structural feature, the processed fluffy tow also has a three-dimensional three-dimensional structure, so the volume of the fluffy tow is large, and a fluffy tow having excellent fluffiness can be obtained. Among the polymers capable of forming fibers, the Young's modulus of the polyester fibers is relatively high, so the fluffy tow produced has good pressure resistance and recovery properties.

The three-dimensional three-dimensional crimped shape means that the fiber appears as an irregular spiral structure in the long direction (Figure 3). At the same time, due to the alignment difference between some of the monofilaments, the rotation modes and directions of the monofilaments are different. Multi-dimensional three-dimensional form.

The polyester hollow long fiber of the present invention is a hollow fiber obtained by melt spinning technology. The molten polyester chip is discharged through a special-shaped hollow spinneret, and then cooled by side blowing and then rolled. During the melt spinning process, adjust the position of the side air blower to change the cooling distance, adjust the wind speed and spinning speed of the side air blower to control the hollowness of the hollow fiber in the range of 20.0% ~ 45.0%, and meanwhile, the curvature of the three-dimensional three-dimensional curly shape The radius is in the range of 10.0mm ~ 50.0mm. Compared with solid fibers, hollow fibers of the same fiber diameter have a higher fluffiness, and the higher the hollowness, the lighter the feeling is. If the radius of curvature of the hollow fiber is too small, the cohesion between the fiber monofilaments is high, the fiber is not easy to open during the processing of the fluffy yarn, and the diameter of the ring formed by the fiber is too small, which affects the fluffiness of the processing tow On the contrary, if the curl radius of the fiber is too large, the diameter of the ring formed by the fiber after being processed into a fluffy tow is too large, which will weaken or fail to reflect the original three-dimensional effect of the sheath fiber, and also affect the fluffyness of the tow.

According to the shape and arrangement of the discharge holes of the hollow spinneret, and the changes in the production process, the cross-sections of the hollow fibers obtained are slightly different. The shapes of the hollow parts are round, approximately triangular, approximately square, and approximately pentagonal. For different shapes, the number of holes on the hollow section is not limited to one hole.

The monofilament fineness range of the hollow polyester long fiber of the present invention is preferably 4.0 dtex to 15.0 dtex. As the raw material fiber for fluff processing tow, the higher the fiber monofilament fineness, the better the rigidity of the fiber, the better the fluffiness of the fluffy tow made, and the better the pressure resistance and recovery. However, if the diameter of the monofilament fiber is too large, it is difficult to cool it during spinning, and the uniformity of the fiber is reduced. At the same time, the feel of the fluffy tow made will be stiff. Therefore, the monofilament range of the better hollow polyester long fiber is 5.0dtex ~ 10.0dtex.

The raw materials of the hollow polyester long fibers of the present invention are mainly ordinary polyesters, such as polyethylene terephthalate, polytrimethylene terephthalate, or polybutylene terephthalate. In order to impart fluffy processing The special functions of silk can also use the modified copolymers of the above polymers, such as antibacterial and anti-mite modified polymers, which can also achieve the same effect as ordinary polyesters in terms of fluffy performance.

Hollow polyester long fiber is one of the raw materials for making fluffy processing tow for filling. It can be directly combined with N to form fluffy processing tow and directly used for filling long cotton. It can also be used in combination with other raw materials, such as melting point. Slightly lower fibers are made into mixed filaments and then used as filled long cotton; or the mixed filaments are further core-sheathed with hollow polyester long fibers and then partially fused to produce more excellent fluffy processed yarns. Bundles are then used to fill long cotton.

The hollow polyester long fiber of the present invention has a three-dimensional three-dimensional shape after being subjected to a dry heat treatment at 160 ° C. for 3 minutes. Due to the effect of fiber thermal contraction, the crimp shape will change. In this case, even after the subsequent processing, the hollow polyester long fiber can still maintain a fluffy three-dimensional three-dimensional crimp shape, and has excellent properties such as hand feel, bulkiness, and heat retention.

The long-fiber polyester hollow long fiber of the present invention can be prepared by the following method, but is not limited to this method: First, the raw polyester chip is dried to reduce the moisture content of the polyester chip, improve spinnability, and control the chip The moisture content is below 50ppm. The dried chips are spun by a general melt spinning method. The chips are melted by a screw or a hot plate and then conveyed to the metering pump through a pipe. After the metering pump accurately measures the melt polymer, it enters the spinning module. The spinneret used in the spinning module is a spinning nozzle for hollow fiber spinning. board. The polymer discharged from the spinneret is taken up after cooling and oiling. In order to obtain hollow fibers with micro-curls, the cooling distance (the distance from the lower edge of the spinneret to the upper edge of the cooling side air blower) during the spinning process is relatively strict. It is generally controlled within the range of 10 to 150 mm, preferably 60. Within ~ 100mm. At the same time, in order to make a difference in the structure of the two sides of the hollow fiber, the wind speed of the side blowing is also required. According to the type of fiber (total fineness and number of filaments), it is generally controlled in the range of 25 ~ 90m / min, preferably 30 ~ 50m / min.

When the cooling distance is less than 10mm, the polymer discharged from the spinneret is rapidly cooled, the asymmetric effect is obvious, the radius of curvature of the obtained fiber will be too small, the cohesion between the fiber monofilaments is high, and the fluffy effect is affected. It is easy to reduce the temperature of the silk plate, leading to fiber breakage and poor spinnability. When the cooling distance is greater than 150mm, the polymer discharged from the spinneret has been uniformly cooled to a certain extent, even if forced cooling is performed by side blowing, asymmetric The effect has also weakened, and the radius of curvature of the obtained fiber will be too large, which will also affect the fluffy effect.

When the wind speed of the side air blow is less than 25m / min, the asymmetric cooling effect is not obvious, and the curvature radius of the fiber is too large; when the wind speed of the side air blow is more than 90m / min, the asymmetric effect is more obvious, resulting in the fiber The curvature radius is too small, and the side blows too much at the same time, resulting in a large swing of the fiber, spinning is unstable, and the phenomenon of floating monofilaments and broken filaments is prone to occur.

In order to prevent the difference in physical properties caused by the difference in cooling between the filaments, the arrangement of the ejection holes of the spinneret is preferably a "thousand bird" arrangement, which is often referred to as a diamond arrangement. Preferably, the spinning process mainly adopts a one-step spinning process, that is, spinning / drawing is completed at the same time, which is commonly known as FDY. However, it can also be made by a two-step method, that is, the fiber that is worthy of pre-orientation first, commonly known as POY, and then drawn through the stretching machine, which is commonly known as DT.

The polyester hollow long fiber according to the present invention has a three-dimensional crimped structure, and at the same time, the fiber monofilament is relatively thick. The fluffy tow made from the hollow long fiber has a high exclusion volume and a high bulkiness, and at the same time has excellent Compression resistance.

The test method involved in the present invention is as follows:

    (1) Test method for total fineness and monofilament fineness    

The total fineness is tested according to JIS L 1013: 2010. The single-filament fineness is calculated by the total fineness and the number of single-filaments.

    (2) Hollow ratio    

The hollow long fiber is cut into thin slices (ie, the fiber cross section) in the longitudinal direction, and is magnified to an appropriate magnification under a common optical microscope to take a picture. The area S ₁ of the hollow portion and the entire area S _{2 of the} fiber (including the hollow) are calculated based on the picture. ), And then calculated: hollow ratio = (S ₁ / S ₂ ) × 100%.

    (3) Test method of curvature radius    

Curvature radius in the natural state: The yarn is passed through a ruler (for fineness measurement) to curl the sample for 10 turns (1 meter / turn), and then the sample to be tested is placed in a constant temperature and humidity environment (20 ° C × 65% RH) ( Hang) for 8 hours or more to stabilize the state (as shown in Figure 3), then select the bend within 20 cm below the sample for radius measurement, select 20 different places to measure and average, the data obtained is the radius of curvature. The measuring instrument is a digital microscope system (VHX-2000C) produced by KEYENCE. The magnification is 20 times. The curvature radius is measured by the curvature radius calculation function in the software (see Figure 4). That is, the curvature radius of the fiber is measured by three positions on the crimped fiber.

Curvature radius after dry heat treatment: The yarn is passed through a ruler (for fineness measurement) to curl the sample for 10 turns, and then placed in a dryer for heat treatment. The processing conditions are 160 ° C × 3min, and then the sample is placed in a constant temperature and humidity environment. Let it stand for more than 4h, and finally select the curved part within 20cm below to measure the radius, and choose 20 different places to measure and average. The resulting data is the radius of curvature.

    (4) Fluffiness    

Test according to the IDFB method: ① First place the sample to be tested in an environment of 20 ° C × 65% RH for 8 hours or more to make the sample to be stable; ② Weigh 30g of the sample and manually shake it After the fluffy state, put it into the measuring barrel and cover it; ③ Move the weight pan down to the highest point where it touches the sample, then release the weight pan to allow it to fall freely, and release the weight pan to time and stabilize. Read the height after 1 minute and record; ④ Open the lid to take out the sample, shake it again to a fluffy state, put the lid in the measuring barrel, measure again according to step ③, test 5 times in the same way; ⑤ calculate 5 times After calculating the average height of the fluffy degree.

The following describes the content of the present invention through examples, but the present invention is not limited to the content listed in the examples.

    Example 1:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 25m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 300T-20f, the hollow section is triangular hollow, the hollowness is 20.0%, the monofilament fineness is 15.0dtex, the curvature radius before heat treatment is 50.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 10.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 390 inches ³ / 30g. See Table 1 for details.

    Example 2:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 40m / min. Hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 150T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 15.0dtex, the curvature radius before heat treatment is 42.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 8.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 600 inches ³ / 30g. See Table 1 for details.

    Example 3:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 40m / min. Hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 60T-4f, the hollow section is triangular hollow, the hollowness is 45.0%, the monofilament fineness is 15.0dtex, the radius of curvature before heat treatment is 37.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 7.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow is 800 inches ³ / 30g. See Table 1 for details.

    Example 4:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 10.0dtex, the curvature radius before heat treatment is 40.0mm, and after dry heat treatment at 160 ° C × 3min The radius of curvature is 7.8mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow is 650 inches ³ / 30g. See Table 1 for details.

    Example 5:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 50m / min. Hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fibers are as follows: the fiber type is 100T-20f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 5.0dtex, the radius of curvature before heat treatment is 35.0mm, and after dry heat treatment at 160 ° C × 3min The radius of curvature is 6.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 610 inches ³ / 30g. See Table 1 for details.

    Example 6:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 75m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 60T-15f, the hollow section is triangular hollow, the hollowness is 45.0%, the monofilament fineness is 4.0dtex, the radius of curvature before heat treatment is 10.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 3.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 480 inches ³ / 30g. See Table 1 for details.

    Example 7:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 70m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 65T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 6.5dtex, the radius of curvature before heat treatment is 30.0mm, and after 160 ° C × 3min dry heat treatment The curvature radius is 6.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 580 inches ³ / 30g. See Table 1 for details.

    Example 8:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 70m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fibers are as follows: the fiber type is 50T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 5.0dtex, the curvature radius before heat treatment is 20.0mm, and after dry heat treatment at 160 ° C × 3min The curvature radius is 4.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 520 inches ³ / 30g. See Table 1 for details.

    Example 9:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 25m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 60T-4f, the hollow section is four corners hollow, the hollowness is 45.0%, the monofilament fineness is 15.0dtex, the curvature radius before heat treatment is 42.0mm, and after dry heat treatment at 160 ° C × 3min The radius of curvature is 8.1mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 760 inches ³ / 30g. See Table 1 for details.

    Example 10:    

The raw materials used were ordinary poly (trimethylene terephthalate) chips (that is, ordinary 3GT), and the poly (trimethylene terephthalate) was dried by a pre-crystallization dehumidifying dryer, and the moisture content after drying was 30 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 38.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 7.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 630 inches ³ / 30g. See Table 1 for details.

    Example 11:    

The raw materials used were ordinary polybutylene terephthalate chips (that is, ordinary PBT), and the polybutylene terephthalate was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 33 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 36.0mm, and after 160 ° C × 3min dry heat treatment The radius of curvature is 7.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 600 inches ³ / 30g. See Table 2 for details.

    Example 12:    

The raw material used was a cation-modified polyethylene terephthalate chip, and this cation-modified polyethylene terephthalate was dried by a pre-crystallization dehumidifier dryer, and the moisture content after drying was 30 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 33.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 33.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 6.4mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 610 inches ³ / 30g. See Table 2 for details.

    Example 13:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded through a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning assembly. The spinneret of the spinning assembly is a hollow spinneret with a cooling distance of 10mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 40.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 12.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 3.6mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 490 inches ³ / 30g. See Table 2 for details.

    Example 14:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded through a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 60mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 37.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 30.0mm, and after dry heat treatment at 160 ° C × 3min The radius of curvature is 6.1mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 600 inches ³ / 30g. See Table 2 for details.

    Example 15:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 90mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fibers are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 32.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 34.0mm, and after dry heat treatment at 160 ° C × 3min The radius of curvature is 9.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 720 inches ³ / 30g. See Table 2 for details.

    Embodiment 16:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 110mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 30.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 38.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 12.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 620 inches ³ / 30g. See Table 2 for details.

    Example 17:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded through a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning assembly. The spinneret of the spinning assembly is a hollow spinneret and the cooling distance is 150mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 25.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 44.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 14.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 550 inches ³ / 30g. See Table 2 for details.

    Embodiment 18:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. With a side air blowing speed of 90m / min, hollow polyester fibers were produced after the DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 35.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 18.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 3.9mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 510 inches ³ / 30g. See Table 2 for details.

    Example 19:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 50m / min. Hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 28.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 28.0mm, and after dry heat treatment at 160 ° C × 3min The curvature radius is 4.5mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow was 530 inches ³ / 30g. See Table 2 for details.

    Comparative Example 1:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded through a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a common circular hole spinneret. The cooling distance is 65mm, the speed of the side blow is 25m / min, and the polyester fiber is obtained after the DSD high-speed spinning process. The characteristics of the fiber are as follows: the fiber type is 56T-24f, the cross section is a solid circle, the monofilament fineness is 2.3 dtex, and there is no crimping property before and after heat treatment. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow is 240 inches ³ / 30g. See Table 3 for details.

Because the cross-section of the fiber is solid, the resulting fiber has no crimp and has a small fluffiness, and is not suitable for use as a filling cotton instead of feathers.

    Comparative Example 2:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 90mm. , The side blowing air speed is 35m / min, hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 10.0%, the monofilament fineness is 10.0dtex, the curvature radius before heat treatment is 40.0mm, and after dry heat treatment at 160 ° C × 3min The radius of curvature is 10.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy Tested tow, the bulk of the test fluffy tow was 310 inches ³ / 30g. See Table 3 for details.

Because the hollowness of the fiber is too small, although it has a radius of curvature, it is poor in lightness and fluffy, so it is not suitable for use as a filling cotton instead of feathers.

    Comparative Example 3:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded through a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 5mm. , The side blowing wind speed is 35m / min, spinning through the DSD high-speed spinning process. Because the cooling distance is too close, although spinning can be performed, the phenomenon of broken yarn and floating yarn is serious, and the feasibility of production is low. See Table 3 for details.

    Comparative Example 4:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. , The side blowing air speed is 110m / min, spinning through the DSD high-speed spinning process. Due to the high wind speed of the side blower, although spinning can be performed, severe fiber breakage leads to severe yarn breakage and drifting, and the feasibility of production is low. See Table 3 for details.

    Comparative Example 5:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melted and extruded through a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 200mm. The side blowing air speed is 70m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 15.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 65.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 23.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow is 350 inches ³ / 30g. See Table 3 for details.

Because the cooling distance is too large, the radius of curvature of the obtained fiber is too large, and the three-dimensional effect of the fiber cannot be reflected, resulting in small fluffiness.

    Comparative Example 6:    

The raw material was a semi-matte polyester chip (T200N produced by Toray Fiber Synthetic Fiber Co., Ltd.), and the polyester chip was dried by a pre-crystal desiccant dryer, and the moisture content after drying was 39 ppm. The dried chips are melt extruded by a screw and conveyed to the metering pump through a pipe. The polymer accurately metered by the metering pump is sent to the spinning module. The spinneret of the spinning module is a hollow spinneret and the cooling distance is 65mm. The side blowing air speed is 20m / min, and hollow polyester fiber is obtained after DSD high-speed spinning process. The characteristics of hollow fiber are as follows: the fiber type is 100T-10f, the hollow section is triangular hollow, the hollowness is 12.0%, the monofilament fineness is 10.0dtex, the radius of curvature before heat treatment is 55.0mm, and after dry heat treatment at 160 ℃ × 3min The radius of curvature is 20.0mm. This fiber is selected as the raw material of the sheath fiber and the core fiber, and fed at a super-feed of a sheath wire feeding speed / core wire feeding speed of 20 times, and processed into a core-sheath fluffy yarn, and 6 combined yarns to obtain fluffy The towability of the processed tow is 350 inches ³ / 30g. See Table 3 for details.

Because the wind speed of the side blowing is too small, the curvature radius of the obtained fiber is too large to reflect the three-dimensional effect of the fiber, resulting in a small fluffiness.

Claims (8)

    A polyester hollow long fiber, characterized in that the cross-section hollowness of the long fiber is 20.0% to 45.0%, the long fiber has a three-dimensional three-dimensional crimp shape in a natural state, and the curvature radius of the crimp shape is 10.0 mm ~ 50.0mm.         The polyester hollow long fiber according to claim 1, wherein the monofilament fineness of the long fiber is 4.0 dtex to 15.0 dtex.         The polyester hollow long fiber according to claim 2, wherein the monofilament fineness of the long fiber is 5.0 dtex to 10.0 dtex.         For example, the polyester hollow long fiber of claim 1 or 2, wherein the radius of curvature of the long fiber after the dry heat treatment at 160 ° C for 3 minutes is 3.5 mm to 10.0 mm.         The polyester hollow long fiber according to claim 1 or 2, wherein the polyester is polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate or their Modified polymer.         A method for preparing polyester hollow long fiber according to claim 1, characterized in that the dried chips are melt-extruded by a screw and conveyed to a metering pump through a pipe, and the polymer accurately metered by the metering pump is sent to spinning The spinneret of the module and the spinning module is a hollow spinneret, with a cooling distance of 10 ~ 150mm, and a side blowing wind speed of 25 ~ 90m / min.         The method for preparing a polyester hollow long fiber according to claim 6, wherein the cooling distance is 60 to 110 mm.         The method for preparing the polyester hollow long fiber according to claim 6 or 7, wherein the wind speed of the side blowing is 30-50 m / min.