Core yarn fracture fuzzing type polyester fiber and preparation method thereof

Abstract

The invention belongs to the technical field of chemical fiber production, and relates to a core yarn broken fluff type polyester fiber and a preparation method thereof.The core yarn broken fluff type polyester fiber is a tow composed of a plurality of monofilaments, one part of the monofilaments are broken, the other part of the monofilaments are unbroken monofilaments, the broken monofilaments are distributed on the inner sides of the unbroken monofilaments, and the unbroken monofilaments are distributed on the inner sides of the unbroken monofilaments. One end of each broken monofilament protrudes to the outer side of the unbroken monofilament; the preparation method comprises the following steps: after a polyester melt enters a spinneret plate to be extruded, cooling, oiling, pre-interlacing, G / R1 hot roller drafting, G / R2 hot roller drafting, main interlacing and winding are performed in sequence to prepare the core yarn breakage fuzzing type polyester fiber; n circles of spinneret orifices with the same aperture are formed in the spinneret plate; the spinneret plate can be divided into an inner spinneret orifice and an outer spinneret orifice from the inner side to the outer side; the upper surface of the spinneret plate is a plane, and the lower surface of the spinneret plate is an arc-shaped bottom surface. According to the invention, polyester fibers with different broken hairiness numbers and densities can be produced, and the prepared product is fluffy and has better resilience.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical fiber production, and relates to a core yarn broken and raised polyester fiber and a preparation method thereof. Background Art

[0002] At present, there are three ways to produce wool yarn polyester fiber.

[0003] The first is that under the action of external force, the single filaments in the filament bundle that are in contact with the external force are broken and protruded to form a feathering effect. For example, in patent CN109295531A, a friction device is used to rub the outer layer of filaments during the drawing process to obtain wool-like FDY, and in patent CN114232156A, a disc with a high friction coefficient and an oil tanker are used to obtain an outer layer of broken wool yarn.

[0004] The second method is to compound the finished fibers and use the difference in shrinkage to form outer terry yarns, which has the effect of broken open fibers. For example, in patent CN110747552A, two yarns are twisted together and shrinkage is used to form terry yarn, and in patent CN101177822A, polyester ATY wool-like yarn is obtained by winding and covering the surface yarn to break.

[0005] The third method is to soften the monofilaments in polyester fibers by the action of acid or alkali to achieve the effect of softening and opening the wool yarn. For example, in patent CN116892074A, an organic acid solution is used to open the polyester-nylon composite ultrafine fibers to obtain acidic open fiber fabrics; in patent CN110106649A, 3%-8% sodium hydroxide impregnation liquid is used to act on the fibers to form an opening process; in patent CN109629265A, yarn washing powder and soda ash are mixed to soften the fibers to form a sand washing softening and opening process.

[0006] However, the wool yarn polyester fibers produced by the above methods are mostly broken or aggregated outer monofilaments, and the formed hairiness is attached hairiness, which only has the velvety feel of wool yarn, and the fabric has poor fluffiness and air permeability, and the fabric does not have resilience.

[0007] Therefore, it is of great significance to study a core yarn broken raised polyester fiber and a preparation method thereof to solve the above problems. Summary of the invention

[0008] The purpose of the present invention is to solve the problems existing in the prior art and provide a core yarn broken raised polyester fiber and a preparation method thereof.

[0009] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] A core yarn broken raised polyester fiber, which is a tow composed of multiple monofilaments, a portion of which are broken, and the rest are unbroken monofilaments, the broken monofilaments are distributed inside the unbroken monofilaments, and one end of all the broken monofilaments protrudes outside the unbroken monofilaments;

[0011] The fineness of the core yarn broken raised polyester fiber is 55~223dtex, the total number of monofilaments is 72~216, dpf≥0.5, and the number of broken monofilaments is 48~62% of the total number of monofilaments.

[0012] As the preferred technical solution:

[0013] The core yarn broken fluffy polyester fiber as described above has a broken hair length of 0.2-0.6 cm, a hair density of 880-2240 strands / m, a breaking strength of 4.10-4.40 cN / dtex, a breaking strength CV value ≤2.90%, a breaking elongation of 28-33%, a breaking elongation CV value ≤6.50%, a bulkiness ≥85%, and a rebound rate ≥90%. The core yarn broken fluffy polyester fiber of the present invention has hairiness formed by the breaking of inner monofilaments, and the broken monofilaments protrude from the inside to the outside (the number of outer monofilaments is small, and the hairiness length of the inner monofilaments after the breaking is much larger than the diameter of the outer circle monofilaments, so the broken monofilaments can be exposed from the surface of the composite yarn) and support the outer monofilaments; the outer monofilaments are supported by the hairiness to form a three-dimensional air barrier, so the fluffiness is good, because the inner monofilaments are broken and protrude around the tow, the hairiness density and length are uniform, and the external shape is not easily changed by external force, and the rebound performance is good.

[0014] The present invention also provides a method for preparing a core yarn broken fluffy polyester fiber as described in any one of the above items, wherein after the polyester melt enters the spinneret for extrusion, it is sequentially subjected to cooling, oiling, pre-internetting, G / R1 hot roller drawing, G / R2 hot roller drawing, main internetting and winding to obtain the core yarn broken fluffy polyester fiber;

[0015] The spinneret is provided with n circles of spinneret holes, n is 4 to 6, and the diameters of the spinneret holes are the same; from the inside to the outside of the spinneret, the spinneret holes from the first circle to the n-1th circle or the n-2th circle are inner spinneret holes, and the spinneret holes in the remaining circles are outer spinneret holes;

[0016] The upper surface of the spinneret is a plane, and the lower surface is provided with an arc-shaped groove. The vertical projection of the arc-shaped groove on the upper surface of the spinneret is a circle. Along the radial direction of the circle, the depth of the corresponding arc-shaped groove gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret; the output end of the outer spinneret hole is located outside the arc-shaped groove, and the output end of the outer spinneret hole cannot be located in the arc-shaped groove, because the aspect ratio of the outer circle is different, even if the outer monofilament will not break, there will be a certain stretching difference, resulting in uneven stretching of the outer monofilament;

[0017] The diameter of the inner spinneret hole is 0.14-0.30 mm, the aspect ratio of the inner spinneret hole is 1.7-2.3, and the aspect ratio of the outer spinneret hole is 2.7-3.3; the total number of spinneret holes is 72-216, and the number of inner spinneret holes is 48-62% of the total number of spinneret holes;

[0018] The draft ratio of the G / R1 hot roller and the G / R2 hot roller is equal to the theoretical draft ratio of the filaments extruded from the outer spinneret, and is greater than the theoretical draft ratio of the filaments extruded from the inner spinneret; the theoretical draft ratio is the draft ratio at which the filaments will not be broken at the speed of the G / R1 hot roller and the speed of the G / R2 hot roller;

[0019] After the polyester melt enters the spinneret, the arc-shaped groove on the lower surface of the spinneret is used to make the thickness of the spinneret gradually increase from the inside to the outside along the radial direction, so as to achieve different effects of the aspect ratio of the spinneret holes in different circles. The aspect ratio of the outer spinneret hole is larger than that of the inner spinneret hole. The residence time of the melt from the entrance to the exit of the outer spinneret hole is longer, and the expansion rate is reduced (the spinneret temperature is high, the residence time is long, the viscosity is reduced, the internal stress is weakened, and the expansion rate is reduced accordingly), and the nozzle stretching is reduced, so that under the subsequent G / R1 hot roller drawing and G / R2 hot roller drawing, the outer monofilament is more It is resistant to pulling, and under different circles, with the increase of aspect ratio, the more resistant the monofilament is to pulling. By reasonably setting the speed of G / R1 hot roller and the speed of G / R2 hot roller, the monofilament extruded from the inner spinneret is broken, while the monofilament extruded from the outer spinneret is not broken. The reason why the monofilament with low nozzle stretching is more resistant to pulling under the subsequent G / R1 hot roller drawing and G / R2 hot roller drawing is that the monofilament with the same fineness extruded from the same spinneret has a limited and consistent relative stretching ratio, and the nozzle stretching of the outer monofilament is smaller than that of the inner monofilament, and the remaining stretching of the outer monofilament is more than that of the inner monofilament, so the outer monofilament is more resistant to pulling.

[0020] As the preferred technical solution:

[0021] The method for preparing a core yarn broken fluffy polyester fiber as described above, wherein the cooling is bidirectional mixed cooling, and the device used for the bidirectional mixed cooling includes a ring-blowing cooling device and a micro-mist cooling device;

[0022] The ring-blowing air cooling device is a prior art, and the ring-blowing air cooling device comprises a ring-blowing air bellows and a ring-blowing filter element; the air bellows comprises a bellows housing and an upper cover plate; the ring-blowing filter element is arranged inside the bellows housing, and the top of the ring-blowing filter element is sealed and connected to the upper cover plate through a ring-blowing filter element sealing gasket; through holes are provided on the upper cover plate and the bottom of the bellows, the inner diameter of the ring-blowing filter element is equal to the inner diameter of the through hole, and the central axis of the ring-blowing filter element coincides with the central axis of the through hole; the central axis of the ring-blowing filter element coincides with the central axis of the spinneret, and the inner diameter of the ring-blowing filter element is greater than or equal to the diameter of the spinneret; wind enters the ring-blowing air box from the air supply port of the ring-blowing air box, blows toward the circumferential surface of the ring-blowing filter element, and enters into the inside of the ring-blowing filter element from the holes on the circumferential surface, thereby cooling the wires passing through the inside of the ring-blowing filter element;

[0023] The micro mist cooling device includes an atomization channel, an atomization connecting pipe, an atomization nozzle, a cooling water pipe, a cooling water solenoid valve, a micro pump, a regulating valve, a pressure detector, a temperature detector, a PLC controller, a conveying pipeline and an ultrasonic atomization system;

[0024] The ultrasonic atomization system is used to provide atomization gas; the ultrasonic atomization system is a prior art;

[0025] The atomizing nozzle is a rod-shaped structure with a hollow interior; a plurality of spray holes are arranged on the circumferential surface of the atomizing nozzle, and the spray holes are connected to the interior of the atomizing nozzle; the atomizing nozzle is placed vertically and located inside the annular air blowing bellows, and the vertical projection of the atomizing nozzle on the spinneret is located inside the first circle of spinneret holes;

[0026] The atomization channel is arranged inside the upper cover plate of the annular air box, one end of the atomization channel is connected to the inside of the atomization nozzle through an atomization connecting pipe, and the other end is connected to the ultrasonic atomization system through a delivery pipeline. The ultrasonic atomization system provides atomization gas, which is sprayed from the atomization nozzle to achieve micro-mist cooling; the diameter of the atomization connecting pipe is 5mm, the spacing between adjacent spinneret holes on the same circle of the spinneret is greater than 6mm, and the vertical projection of the atomization connecting pipe on the spinneret does not contact the spinneret holes;

[0027] The number of atomizing connecting pipes, atomizing channels and atomizing nozzles is the same as the number of ring-blowing filter elements, and each ring-blowing filter element corresponds to an atomizing connecting pipe, atomizing channel and atomizing nozzle;

[0028] The cooling water pipe is connected to the ultrasonic atomization system. A cooling water solenoid valve is provided on the cooling water pipe. The cooling water solenoid valve is used to adjust the flow rate of cold water entering the ultrasonic atomization system.

[0029] The regulating valve, the pressure detector, the temperature detector and the micro pump are arranged on the delivery pipeline; the micro pump is arranged closer to the ultrasonic atomization system than the regulating valve, the pressure detector and the temperature detector; the micro pump is used to pressurize the atomization gas in the delivery pipeline;

[0030] The regulating valve, pressure detector, temperature detector and cooling water solenoid valve are all electrically connected to the PLC controller;

[0031] The temperature detector is used to detect the temperature of the atomizing gas in the delivery pipeline, and sends the measured temperature of the atomizing gas to the PLC controller and compares it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomizing gas and the set temperature exceeds 0.5°C, the PLC controller adjusts the cooling water solenoid valve to control the flow of cold water to achieve a stable atomizing gas temperature.

[0032] The regulating valve is used to adjust the pressure of the delivery pipeline;

[0033] The pressure detector is used to detect the atomizing gas pressure, and send the measured atomizing gas pressure to the PLC controller, and compare it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve to stabilize the atomizing gas pressure.

[0034] Bidirectional mixed cooling includes mist cooling and annular air cooling. The mist cooling rapidly cools the monofilaments extruded from the inner spinneret, and the annular air cooling conventionally cools the monofilaments extruded from the outer spinneret, thereby making the composite yarn brittle inside and tough outside, and making full preparation for the preparation of the inner core yarn broken raised polyester fiber (that is, at the speed of G / R1 hot roller and the speed of G / R2 hot roller, the monofilaments extruded from the inner spinneret are easier to be broken, while the monofilaments extruded from the outer spinneret are less likely to be broken).

[0035] According to the method for preparing a core yarn broken raised polyester fiber as described above, a tension detection device is provided between the G / R1 hot roller and the G / R2 hot roller, the tension detection device includes a tension sensor, and the tension detection device is used to detect the tension when all the monofilaments extruded from the inner spinneret holes are broken (the inner monofilament breaking tension is much greater than the stretching tension, so the tension detection sensor detects the tension when broken, rather than the overall tension of the composite yarn), and detects in real time whether all the inner monofilaments are broken; wherein, the tension when all the monofilaments extruded from the inner spinneret holes are broken = the inner monofilament fineness × the sum of the breaking strength of the pre-oriented yarn of the inner monofilament, and the stretching tension can be adjusted by adjusting the speed of the G / R1 hot roller. If the tension is low, the speed of the G / R1 hot roller is reduced, the stretching ratio is increased, and the tension is increased; when the tension is low, the opposite adjustment is made.

[0036] The method for preparing a core yarn broken raised polyester fiber as described above, the process parameters include: the temperature of the spinning box is 280~295℃, the power of the micro-mist cooling pump is 10~15W, the temperature of the atomizing gas is 15~19℃, the pressure of the atomizing gas is 30~50 Pa, the temperature of the annular blowing air is 19~22℃, the wind speed of the annular blowing air is 0.2~0.5m / s, the speed of the oil pump is 3.5~9.5r / min, the pre-network pressure is 0.10~0.15MPa, the speed of the G / R1 hot roller is 1900~2200m / min, the tension is 84~290cN, the speed of the G / R2 hot roller is 3900~4200m / min, and the main network pressure is 0.25~0.35MPa.

[0037] Beneficial effects:

[0038] (1) The present invention controls the aspect ratio of the inner spinneret holes on the spinneret to gradually increase, so that the residence time of the melt in the spinneret holes of different circles is different (the higher the spinneret temperature, the longer the residence time, the lower the viscosity, the weaker the internal stress, and the lower the expansion rate), and the drawing ratio is also different. In the subsequent drawing process, the larger the aspect ratio, the more resistant the single filament is to drawing. By forming this inner and outer drawing difference, the broken hairiness in the prepared polyester fiber finally has a gradual level (that is, the innermost circle is the first and easiest to break, and the degree of breakage is gradually weaker than the innermost circle as it develops outward, forming broken hairiness with a gradual level).

[0039] (2) The present invention rapidly cools the monofilaments extruded from the inner spinneret through micro-mist cooling, and conventionally cools the monofilaments extruded from the outer spinneret through annular air cooling, thereby making the composite yarn brittle inside and tough outside. When the composite yarn is stretched, the monofilaments extruded from the inner spinneret can be more easily broken, while the monofilaments extruded from the outer spinneret are less likely to be broken.

[0040] (3) The present invention can produce polyester fibers with different numbers and densities of broken hairiness by controlling the number of inner spinneret holes on the spinneret and the degree of difference in aspect ratio (the greater the difference, the more and denser the hairiness), so that the obtained product is fluffy and has better resilience. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of the distribution of spinneret holes on the spinneret of the present invention;

[0042] Figure 2 Schematic cross-sectional view of a spinneret hole of the present invention;

[0043] Figure 3 It is a schematic diagram of the ring-blowing cooling device of the present invention;

[0044] Figure 4 is a schematic diagram of the micro mist cooling device of the present invention;

[0045] Figure 5 Schematic diagram of the core yarn broken raised polyester fiber of the present invention;

[0046] Among them: 1-spinneret, 3-spinneret hole, 4-arc groove, 5-bellows cover, 6-ring blowing filter element sealing gasket, 7-ring blowing filter element, 8-air supply port, 10-atomization channel, 11-atomization connecting pipe, 12-atomization nozzle, 13-cooling water pipe, 14-cooling water solenoid valve, 15-ultrasonic atomization system, 16-micro pump, 17-regulating valve, 18-pressure detector; 19-temperature detector, 20-delivery pipeline, 21-broken monofilament, 22-unbroken monofilament. DETAILED DESCRIPTION

[0047] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0048] The aspect ratio of the inner spinneret on the spinneret of the present invention is calculated as follows: the outlet of the inner spinneret hole is a curved surface, and the aspect ratio of the inner spinneret hole=spinneret hole length / spinneret hole diameter; wherein the spinneret hole length is the length from point A to point B, point A is the point where the central axis of the spinneret hole intersects with the plane where the top of the spinneret hole is located, and point B is the point where the central axis of the spinneret hole intersects with the curved surface where the outlet of the spinneret hole is located.

[0049] The testing methods of the relevant performance indicators in the following embodiments and comparative examples are as follows:

[0050] dpf: first refer to GB / T14343-2008 Test method for linear density of chemical fiber filaments to test the total fiber density of the core yarn broken raised polyester fiber prepared in the example, and then divide it by the total number of monofilaments.

[0051] Breaking strength, breaking strength CV value, breaking elongation, breaking elongation CV value: referring to the standard "GB / T 14344-2008 Test method for tensile properties of synthetic filaments", the core yarn broken raised polyester fibers prepared in each embodiment were tested using an imported fully automatic strength and elongation tester.

[0052] Fluffiness: The core yarn broken and raised polyester fiber prepared in the example was tested with reference to GB / T 10288-2016 Testing method for down and feathers.

[0053] Rebound rate: with reference to the standard "FZ / T 01034-2008 Test method for tensile elasticity of woven fabrics for textiles", the core yarn broken raised polyester fiber prepared in the embodiment was deformed by stretching at a fixed length and a fixed force using a constant rate of elongation tester. The stretching process was stretched from an initial length of 100 mm to 115 mm, and the stretching speed was 20 mm / min. After the tensile force was released, the residual elongation was measured after recovery within a specified time, and then the elastic recovery rate was calculated by the calculation formula: (L0-δL1) / (L0-δL)×100%, wherein L0 is the total length of the sample after stretching, δL is the length of the sample after pre-tensioning, and δL1 is the length of the sample after the pre-tensioning force is applied again after the sample recovers from the fixed force or fixed elongation (plastic deformation).

[0054] Example 1

[0055] A method for preparing a core yarn broken fluffy polyester fiber, the specific process is as follows:

[0056] (1) polycondensing PTA (terephthalic acid) and MEG (monoethylene glycol) in a mass ratio of 2.55:1 to form a polyester melt with an intrinsic viscosity of 0.695±0.004 dl / g;

[0057] (2) The polyester melt enters the spinning box, is extruded through the spinneret, and then goes through cooling, oiling, pre-internetting, G / R1 hot roller drawing, G / R2 hot roller drawing, main internetting and winding to obtain the core yarn broken fluffy polyester fiber;

[0058] Among them, Figure 1 , Figure 2 As shown, the upper surface of the spinneret 1 is a plane, and the lower surface is provided with an arc-shaped groove 4, the vertical projection of the arc-shaped groove 4 on the spinneret 1 is a circle, and along the radial direction of the circle, the depth of the arc-shaped groove 4 gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret;

[0059] The spinneret 1 is provided with 5 circles of spinneret holes 3, and the diameters of the spinneret holes 3 are the same; from the inside to the outside of the spinneret 1, the spinneret holes 3 in the first to third circles are inner spinneret holes, and the spinneret holes 3 in the remaining circles are outer spinneret holes; the diameter of the inner spinneret holes is 0.19 mm, the aspect ratios of the inner spinneret holes in the first to third circles are 1.7, 2.0, and 2.3, respectively, and the aspect ratio of the outer spinneret holes is 2.9; the number of spinneret holes 3 is 144, the number of inner spinneret holes is 50% of the total number of spinneret holes 3, and the number of spinneret holes in each circle from the first to the fifth circle is 20, 24, 28, 32, and 40, respectively;

[0060] The cooling adopts two-way mixed cooling, and the devices used for the two-way mixed cooling include a ring-blowing cooling device and a micro-mist cooling device;

[0061] like Figure 3 As shown, the annular air cooling device includes an annular air box and an annular air filter 7; the air box includes an air box body and an upper cover plate 5; the annular air filter 7 is arranged inside the air box body, and the top of the annular air filter 7 is sealed and connected to the upper cover plate 5 through an annular air filter sealing gasket 6;

[0062] like Figure 3 , Figure 4 As shown, the micro mist cooling device includes an atomization channel 10, an atomization connecting pipe 11, an atomization nozzle 12, a cooling water pipe 13, a cooling water solenoid valve 14, an ultrasonic atomization system 15, a micro pump 16, a regulating valve 17, a pressure detector 18, a temperature detector 19, a PLC controller and a delivery pipeline 20;

[0063] The ultrasonic atomization system 15 is used to provide atomization gas;

[0064] The atomizing nozzle 12 is a rod-shaped structure with a hollow interior; a plurality of spray holes are provided on the circumferential surface of the atomizing nozzle 12, and the spray holes are connected to the interior of the atomizing nozzle 12; the atomizing nozzle 12 is placed vertically and located inside the annular blowing bellows, and the vertical projection of the atomizing nozzle 12 on the spinneret 1 is located inside the first circle of spinneret holes 3;

[0065] The atomizing channel 10 is arranged inside the upper cover plate of the annular blowing bellows, one end of the atomizing channel 10 is connected to the inside of the atomizing nozzle 12 through the atomizing connecting pipe 11, and the other end is connected to the ultrasonic atomizing system through the conveying pipe 20, and the vertical projection of the atomizing connecting pipe 11 on the spinneret 1 does not contact the spinneret hole 3;

[0066] The number of the atomizing connecting pipe 11, the atomizing channel 10 and the atomizing nozzle 12 is the same as the number of the ring-blowing filter element 7;

[0067] The cooling water pipe 13 is connected to the ultrasonic atomization system. A cooling water solenoid valve 14 is provided on the cooling water pipe 13. The cooling water solenoid valve 14 is used to adjust the flow rate of cold water entering the ultrasonic atomization system.

[0068] The regulating valve 17, the pressure detector 18, the temperature detector 19 and the micro pump 16 are arranged on the delivery pipeline 20; the micro pump 16 is arranged closer to the ultrasonic atomization system than the regulating valve 17, the pressure detector 18 and the temperature detector 19; the micro pump 16 is used to pressurize the atomization gas in the delivery pipeline 20;

[0069] The regulating valve 17, the pressure detector 18, the temperature detector 19 and the cooling water solenoid valve 14 are all electrically connected to the PLC controller;

[0070] The temperature detector 19 is used to detect the temperature of the atomized gas in the delivery pipeline 20, and send the measured temperature of the atomized gas to the PLC controller, and compare it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomized gas and the set temperature exceeds 0.5°C, the PLC controller adjusts the cooling water solenoid valve 14 to control the flow of cold water;

[0071] The regulating valve 17 is used to adjust the pressure of the delivery pipeline 20;

[0072] The pressure detector 18 is used to detect the atomizing gas pressure, and send the measured atomizing gas pressure to the PLC controller, and compare it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve 17;

[0073] A tension detection device is provided between the G / R1 heat roller and the G / R2 heat roller;

[0074] The process parameters include: the temperature of the spinning box is 285°C, the power of the micro-mist cooling pump is 12W, the temperature of the atomizing gas is 17°C, the pressure of the atomizing gas is 40Pa, the temperature of the annular air is 21°C, the wind speed of the annular air is 0.3m / s, the speed of the oil pump is 6.5r / min, the pre-network pressure is 0.125MPa, the speed of the G / R1 hot roller is 2050m / min, the tension of all single filaments extruded from the inner spinneret when they break is 138cN, the speed of the G / R2 hot roller is 4000m / min, and the main network pressure is 0.29MPa.

[0075] The core yarn broken fluffy polyester fiber finally obtained is as follows Figure 5 As shown, it is a tow composed of multiple monofilaments, some of which are broken, and the rest are unbroken monofilaments 22, the broken monofilaments 21 are distributed on the inner side of the unbroken monofilaments 22, and one end of all the broken monofilaments 21 protrudes to the outer side of the unbroken monofilaments 22; the fineness of the core yarn broken raised polyester fiber is 112.76 dtex, the total number of monofilaments is 144, the dpf is 0.783, and the number of broken monofilaments is 50% of the total number of monofilaments; the broken hairiness of the core yarn broken raised polyester fiber has a gradual level, the broken hairiness length is 0.2~0.6cm, the hairiness density is 1480 pieces / m, the breaking strength is 4.16 cN / dtex, the breaking strength CV value is 1.97%, the breaking elongation is 31.3%, the breaking elongation CV value is 3.78%, the fluffiness is 89%, and the rebound rate is 90%.

[0076] Example 2

[0077] A method for preparing a core yarn broken fluffy polyester fiber, the specific process is as follows:

[0078] (1) polycondensing PTA and MEG in a mass ratio of 2.55:1 to form a polyester melt having an intrinsic viscosity of 0.695±0.004 dl / g;

[0079] (2) The polyester melt enters the spinning box, is extruded through the spinneret, and then goes through cooling, oiling, pre-internetting, G / R1 hot roller drawing, G / R2 hot roller drawing, main internetting and winding to obtain the core yarn broken fluffy polyester fiber;

[0080] The upper surface of the spinneret is a plane, and the lower surface is provided with an arc-shaped groove, the vertical projection of the arc-shaped groove on the spinneret is a circle, and along the radial direction of the circle, the depth of the arc-shaped groove gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret;

[0081] The spinneret is provided with 5 circles of spinneret holes, and the diameters of the spinneret holes are the same; from the inside to the outside of the spinneret, the spinneret holes in the first to third circles are inner spinneret holes, and the spinneret holes in the remaining circles are outer spinneret holes; the diameter of the inner spinneret holes is 0.14 mm, and the aspect ratios of the inner spinneret holes in the first to third circles are 1.7, 2.0, and 2.3, respectively, and the aspect ratio of the outer spinneret holes is 2.7; the number of spinneret holes is 144, the number of inner spinneret holes is 50% of the total number of spinneret holes, and the number of spinneret holes in each circle from the first to the fifth circle is 20, 24, 28, 32, and 40, respectively;

[0082] The cooling adopts two-way mixed cooling, and the devices used for the two-way mixed cooling include a ring-blowing cooling device and a micro-mist cooling device;

[0083] The annular air cooling device comprises an annular air bellows and an annular air filter element; the annular air bellows comprises an air box body and an upper cover plate; the annular air filter element is arranged inside the air box body, and the top of the annular air filter element is sealed and connected to the upper cover plate through an annular air filter element sealing gasket;

[0084] The micro mist cooling device includes an atomization channel, an atomization connecting pipe, an atomization nozzle, a cooling water pipe, a cooling water solenoid valve, an ultrasonic atomization system, a micro pump, a regulating valve, a pressure detector, a temperature detector, a PLC controller, a conveying pipeline and an ultrasonic atomization system;

[0085] An ultrasonic atomization system is used to provide atomization gas;

[0086] The atomizing nozzle is a rod-shaped structure with a hollow interior; a plurality of spray holes are arranged on the circumferential surface of the atomizing nozzle, and the spray holes are connected to the interior of the atomizing nozzle; the atomizing nozzle is placed vertically and located inside the annular air blowing bellows, and the vertical projection of the atomizing nozzle on the spinneret is located inside the first circle of spinneret holes;

[0087] The atomizing channel is arranged inside the upper cover plate of the annular blowing bellows, one end of the atomizing channel is connected to the inside of the atomizing nozzle through an atomizing connecting pipe, and the other end is connected to the ultrasonic atomizing system through a conveying pipeline, and the vertical projection of the atomizing connecting pipe on the spinneret does not contact the spinneret hole;

[0088] The number of atomizing connecting pipes, atomizing channels and atomizing nozzles is the same as the number of ring-blowing filter elements;

[0089] The cooling water pipe is connected to the ultrasonic atomization system. A cooling water solenoid valve is provided on the cooling water pipe. The cooling water solenoid valve is used to adjust the flow rate of cold water entering the ultrasonic atomization system.

[0090] The regulating valve, the pressure detector, the temperature detector and the micro pump are arranged on the delivery pipeline; the micro pump is arranged closer to the ultrasonic atomization system than the regulating valve, the pressure detector and the temperature detector; the micro pump is used to pressurize the atomization gas in the delivery pipeline;

[0091] The regulating valve, pressure detector, temperature detector and cooling water solenoid valve are all electrically connected to the PLC controller;

[0092] The temperature detector is used to detect the temperature of the atomized gas in the delivery pipeline, and send the measured temperature of the atomized gas to the PLC controller and compare it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomized gas and the set temperature exceeds 0.5°C, the PLC controller adjusts the cooling water solenoid valve to control the flow of cold water;

[0093] The regulating valve is used to adjust the pressure of the delivery pipeline;

[0094] The pressure detector is used to detect the atomizing gas pressure, and send the measured atomizing gas pressure to the PLC controller, and compare it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve;

[0095] A tension detection device is provided between the G / R1 heat roller and the G / R2 heat roller;

[0096] The process parameters include: the temperature of the spinning box is 290℃, the power of the micro-mist cooling pump is 12W, the temperature of the atomizing gas is 17℃, the pressure of the atomizing gas is 40Pa, the temperature of the annular air is 20℃, the wind speed of the annular air is 0.2m / s, the speed of the oil pump is 5r / min, the pre-network pressure is 0.1MPa, the speed of G / R1 hot roller is 2200m / min, the tension of all single filaments extruded from the inner spinneret when they break is 103cN, the speed of G / R2 hot roller is 3900m / min, and the main network pressure is 0.25MPa.

[0097] The core yarn broken fluffy polyester fiber finally obtained is a tow composed of multiple monofilaments, some of which are broken and the rest are unbroken monofilaments, the broken monofilaments are distributed on the inner side of the unbroken monofilaments, and one end of all the broken monofilaments protrudes to the outer side of the unbroken monofilaments; the fineness of the core yarn broken fluffy polyester fiber is 83.64 dtex, the total number of monofilaments is 144, the dpf is 0.581, and the number of broken monofilaments is 50% of the total number of monofilaments; the broken hairiness of the core yarn broken fluffy polyester fiber has a gradual level, the broken hairiness length is 0.2~0.6cm, the hairiness density is 1390 filaments / m, the breaking strength is 4.25 cN / dtex, the breaking strength CV value is 2.18%, the breaking elongation is 28.6%, the breaking elongation CV value is 3.32%, the fluffiness is 91%, and the rebound rate is 92%.

[0098] Example 3

[0099] A method for preparing a core yarn broken fluffy polyester fiber, the specific process is as follows:

[0100] (1) polycondensing PTA and MEG in a mass ratio of 2.55:1 to form a polyester melt having an intrinsic viscosity of 0.695±0.004 dl / g;

[0101] (2) The polyester melt enters the spinning box, is extruded through the spinneret, and then goes through cooling, oiling, pre-internetting, G / R1 hot roller drawing, G / R2 hot roller drawing, main internetting and winding to obtain the core yarn broken fluffy polyester fiber;

[0102] The upper surface of the spinneret is a plane, and the lower surface is provided with an arc-shaped groove, the vertical projection of the arc-shaped groove on the spinneret is a circle, and along the radial direction of the circle, the depth of the arc-shaped groove gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret;

[0103] The spinneret is provided with 5 circles of spinneret holes, and the hole diameters of the spinneret holes are the same; from the inside to the outside of the spinneret plate, the spinneret holes in the first to third circles are the inner spinneret holes, and the spinneret holes in the remaining circles are the outer spinneret holes; the hole diameter of the inner spinneret holes is 0.29 mm, the aspect ratios of the inner spinneret holes in the first to third circles are 1.7, 2.0, and 2.3 respectively, and the aspect ratio of the outer spinneret holes is 3; the number of spinneret holes is 216, the number of inner spinneret holes is 48% of the total number of spinneret holes, and the number of spinneret holes in each circle from the first to the fifth circle is 24, 36, 44, 52, and 60 respectively;

[0104] The cooling adopts two-way mixed cooling, and the devices used for the two-way mixed cooling include a ring-blowing cooling device and a micro-mist cooling device;

[0105] The annular air cooling device comprises an annular air bellows and an annular air filter element; the annular air bellows comprises an air box body and an upper cover plate; the annular air filter element is arranged inside the air box body, and the top of the annular air filter element is sealed and connected to the upper cover plate through an annular air filter element sealing gasket;

[0106] The micro mist cooling device includes an atomization channel, an atomization connecting pipe, an atomization nozzle, a cooling water pipe, a cooling water solenoid valve, an ultrasonic atomization system, a micro pump, a regulating valve, a pressure detector, a temperature detector, a PLC controller, a conveying pipeline and an ultrasonic atomization system;

[0107] An ultrasonic atomization system is used to provide atomization gas;

[0108] The atomizing nozzle is a rod-shaped structure with a hollow interior; a plurality of spray holes are arranged on the circumferential surface of the atomizing nozzle, and the spray holes are connected to the interior of the atomizing nozzle; the atomizing nozzle is placed vertically and located inside the annular air blowing bellows, and the vertical projection of the atomizing nozzle on the spinneret is located inside the first circle of spinneret holes;

[0109] The atomizing channel is arranged inside the upper cover plate of the annular blowing bellows, one end of the atomizing channel is connected to the inside of the atomizing nozzle through an atomizing connecting pipe, and the other end is connected to the ultrasonic atomizing system through a conveying pipeline, and the vertical projection of the atomizing connecting pipe on the spinneret does not contact the spinneret hole;

[0110] The number of atomizing connecting pipes, atomizing channels and atomizing nozzles is the same as the number of ring-blowing filter elements;

[0111] The cooling water pipe is connected to the ultrasonic atomization system. A cooling water solenoid valve is provided on the cooling water pipe. The cooling water solenoid valve is used to adjust the flow rate of cold water entering the ultrasonic atomization system.

[0112] The regulating valve, the pressure detector, the temperature detector and the micro pump are arranged on the delivery pipeline; the micro pump is arranged closer to the ultrasonic atomization system than the regulating valve, the pressure detector and the temperature detector; the micro pump is used to pressurize the atomization gas in the delivery pipeline;

[0113] The regulating valve, pressure detector, temperature detector and cooling water solenoid valve are all electrically connected to the PLC controller;

[0114] The temperature detector is used to detect the temperature of the atomized gas in the delivery pipeline, and send the measured temperature of the atomized gas to the PLC controller and compare it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomized gas and the set temperature exceeds 0.5°C, the PLC controller adjusts the cooling water solenoid valve to control the flow of cold water;

[0115] The regulating valve is used to adjust the pressure of the delivery pipeline;

[0116] The pressure detector is used to detect the atomizing gas pressure, and send the measured atomizing gas pressure to the PLC controller, and compare it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve;

[0117] A tension detection device is provided between the G / R1 heat roller and the G / R2 heat roller;

[0118] The process parameters include: the temperature of the spinning box is 295°C, the power of the micro-mist cooling pump is 15W, the temperature of the atomizing gas is 15°C, the pressure of the atomizing gas is 45Pa, the temperature of the annular air is 19°C, the wind speed of the annular air is 0.5m / s, the speed of the oil pump is 8r / min, the pre-network pressure is 0.13MPa, the speed of the G / R1 hot roller is 2100m / min, the tension of all single filaments extruded from the inner spinneret when they break is 201cN, the speed of the G / R2 hot roller is 4200m / min, and the main network pressure is 0.3MPa.

[0119] The core yarn broken fluffy polyester fiber finally obtained is a tow composed of multiple monofilaments, some of which are broken and the rest are unbroken monofilaments, the broken monofilaments are distributed on the inner side of the unbroken monofilaments, and one end of all the broken monofilaments protrudes to the outer side of the unbroken monofilaments; the fineness of the core yarn broken fluffy polyester fiber is 167.18 dtex, the total number of monofilaments is 216, the dpf is 0.773, and the number of broken monofilaments is 48% of the total number of monofilaments; the broken hairiness of the core yarn broken fluffy polyester fiber has a gradual level, the broken hairiness length is 0.2~0.6cm, the hairiness density is 2070 filaments / m, the breaking strength is 4.35 cN / dtex, the breaking strength CV value is 0.49%, the breaking elongation is 32.9%, the breaking elongation CV value is 5.24%, the fluffiness is 87%, and the rebound rate is 92%.

[0120] Example 4

[0121] A method for preparing a core yarn broken fluffy polyester fiber, the specific process is as follows:

[0122] (1) polycondensing PTA and MEG in a mass ratio of 2.55:1 to form a polyester melt having an intrinsic viscosity of 0.695±0.004 dl / g;

[0123] (2) The polyester melt enters the spinning box, is extruded through the spinneret, and then goes through cooling, oiling, pre-internetting, G / R1 hot roller drawing, G / R2 hot roller drawing, main internetting and winding to obtain the core yarn broken fluffy polyester fiber;

[0124] The upper surface of the spinneret is a plane, and the lower surface is provided with an arc-shaped groove, the vertical projection of the arc-shaped groove on the spinneret is a circle, and along the radial direction of the circle, the depth of the arc-shaped groove gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret;

[0125] The spinneret is provided with 4 circles of spinneret holes, and the hole diameters of the spinneret holes are the same; from the inside to the outside of the spinneret plate, the spinneret holes in the first to third circles are the inner spinneret holes, and the spinneret holes in the remaining circles are the outer spinneret holes; the hole diameter of the inner spinneret holes is 0.19 mm, and the aspect ratios of the inner spinneret holes in the first to third circles are 1.7, 2.0, and 2.3 respectively, and the aspect ratio of the outer spinneret holes is 3.3; the number of spinneret holes is 72, and the number of inner spinneret holes accounts for 61% of the total number of spinneret holes, and the number of spinneret holes in each circle from the first to the fourth circle is 8, 12, 24, and 28 respectively;

[0126] The cooling adopts two-way mixed cooling, and the devices used for the two-way mixed cooling include a ring-blowing cooling device and a micro-mist cooling device;

[0127] The annular air cooling device comprises an annular air bellows and an annular air filter element; the annular air bellows comprises an air box body and an upper cover plate; the annular air filter element is arranged inside the air box body, and the top of the annular air filter element is sealed and connected to the upper cover plate through an annular air filter element sealing gasket;

[0128] The micro mist cooling device includes an atomization channel, an atomization connecting pipe, an atomization nozzle, a cooling water pipe, a cooling water solenoid valve, an ultrasonic atomization system, a micro pump, a regulating valve, a pressure detector, a temperature detector, a PLC controller, a conveying pipeline and an ultrasonic atomization system;

[0129] An ultrasonic atomization system is used to provide atomization gas;

[0130] The atomizing nozzle is a rod-shaped structure with a hollow interior; a plurality of spray holes are arranged on the circumferential surface of the atomizing nozzle, and the spray holes are connected to the interior of the atomizing nozzle; the atomizing nozzle is placed vertically and located inside the annular air blowing bellows, and the vertical projection of the atomizing nozzle on the spinneret is located inside the first circle of spinneret holes;

[0131] The atomizing channel is arranged inside the upper cover plate of the annular blowing bellows, one end of the atomizing channel is connected to the inside of the atomizing nozzle through an atomizing connecting pipe, and the other end is connected to the ultrasonic atomizing system through a conveying pipeline, and the vertical projection of the atomizing connecting pipe on the spinneret does not contact the spinneret hole;

[0132] The number of atomizing connecting pipes, atomizing channels and atomizing nozzles is the same as the number of ring-blowing filter elements;

[0133] The cooling water pipe is connected to the ultrasonic atomization system. A cooling water solenoid valve is provided on the cooling water pipe. The cooling water solenoid valve is used to adjust the flow rate of cold water entering the ultrasonic atomization system.

[0134] The regulating valve, the pressure detector, the temperature detector and the micro pump are arranged on the delivery pipeline; the micro pump is arranged closer to the ultrasonic atomization system than the regulating valve, the pressure detector and the temperature detector; the micro pump is used to pressurize the atomization gas in the delivery pipeline;

[0135] The regulating valve, pressure detector, temperature detector and cooling water solenoid valve are all electrically connected to the PLC controller;

[0136] The temperature detector is used to detect the temperature of the atomized gas in the delivery pipeline, and send the measured temperature of the atomized gas to the PLC controller and compare it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomized gas and the set temperature exceeds 0.5°C, the PLC controller adjusts the cooling water solenoid valve to control the flow of cold water;

[0137] The regulating valve is used to adjust the pressure of the delivery pipeline;

[0138] The pressure detector is used to detect the atomizing gas pressure, and send the measured atomizing gas pressure to the PLC controller, and compare it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve;

[0139] A tension detection device is provided between the G / R1 heat roller and the G / R2 heat roller;

[0140] The process parameters include: the temperature of the spinning box is 280°C, the power of the micro-mist cooling pump is 10W, the temperature of the atomizing gas is 19°C, the pressure of the atomizing gas is 30Pa, the temperature of the annular air is 22°C, the wind speed of the annular air is 0.3m / s, the speed of the oil pump is 3.5r / min, the pre-network pressure is 0.12MPa, the speed of the G / R1 hot roller is 2100m / min, the tension of all single filaments extruded from the inner spinneret when they break is 84cN, the speed of the G / R2 hot roller is 4000m / min, and the main network pressure is 0.29MPa.

[0141] The core yarn broken fluffy polyester fiber finally obtained is a tow composed of multiple monofilaments, some of which are broken and the rest are unbroken monofilaments, the broken monofilaments are distributed on the inner side of the unbroken monofilaments, and one end of all the broken monofilaments protrudes to the outer side of the unbroken monofilaments; the fineness of the core yarn broken fluffy polyester fiber is 56.53 dtex, the total number of monofilaments is 72, the dpf is 0.785, and the number of broken monofilaments is 61% of the total number of monofilaments; the broken hairiness of the core yarn broken fluffy polyester fiber has a gradual level, the broken hairiness length is 0.2~0.6 cm, the hairiness density is 880 filaments / m, the breaking strength is 4.18 cN / dtex, the breaking strength CV value is 2.87%, the breaking elongation is 30.2%, the breaking elongation CV value is 4.63%, the fluffiness is 87%, and the rebound rate is 90%.

[0142] Example 5

[0143] A method for preparing a core yarn broken fluffy polyester fiber, the specific process is as follows:

[0144] (1) polycondensing PTA and MEG in a mass ratio of 2.55:1 to form a polyester melt having an intrinsic viscosity of 0.695±0.004 dl / g;

[0145] (2) The polyester melt enters the spinning box, is extruded through the spinneret, and then goes through cooling, oiling, pre-internetting, G / R1 hot roller drawing, G / R2 hot roller drawing, main internetting and winding to obtain the core yarn broken fluffy polyester fiber;

[0146] The upper surface of the spinneret is a plane, and the lower surface is provided with an arc-shaped groove, the vertical projection of the arc-shaped groove on the spinneret is a circle, and along the radial direction of the circle, the depth of the arc-shaped groove gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret;

[0147] The spinneret is provided with 6 circles of spinneret holes, and the hole diameters of the spinneret holes are the same; from the inside to the outside of the spinneret plate, the spinneret holes in the first to fourth circles are inner spinneret holes, and the spinneret holes in the remaining circles are outer spinneret holes; the hole diameter of the inner spinneret holes is 0.25 mm, and the aspect ratios of the inner spinneret holes in the first to third circles are 1.7, 1.9, 2.1, and 2.3 respectively, and the aspect ratio of the outer spinneret holes is 3.2; the number of spinneret holes is 216, the number of inner spinneret holes is 52% of the total number of spinneret holes, and the number of spinneret holes in each circle from the first to the sixth circle is 16, 24, 32, 40, 48, and 56 respectively;

[0148] The cooling adopts two-way mixed cooling, and the devices used for the two-way mixed cooling include a ring-blowing cooling device and a micro-mist cooling device;

[0149] The annular air cooling device comprises an annular air bellows and an annular air filter element; the annular air bellows comprises an air box body and an upper cover plate; the annular air filter element is arranged inside the air box body, and the top of the annular air filter element is sealed and connected to the upper cover plate through an annular air filter element sealing gasket;

[0150] The micro mist cooling device includes an atomization channel, an atomization connecting pipe, an atomization nozzle, a cooling water pipe, a cooling water solenoid valve, an ultrasonic atomization system, a micro pump, a regulating valve, a pressure detector, a temperature detector, a PLC controller, a conveying pipeline and an ultrasonic atomization system;

[0151] An ultrasonic atomization system is used to provide atomization gas;

[0152] The atomizing nozzle is a rod-shaped structure with a hollow interior; a plurality of spray holes are arranged on the circumferential surface of the atomizing nozzle, and the spray holes are connected to the interior of the atomizing nozzle; the atomizing nozzle is placed vertically and located inside the annular air blowing bellows, and the vertical projection of the atomizing nozzle on the spinneret is located inside the first circle of spinneret holes;

[0153] The atomizing channel is arranged inside the upper cover plate of the annular blowing bellows, one end of the atomizing channel is connected to the inside of the atomizing nozzle through an atomizing connecting pipe, and the other end is connected to the ultrasonic atomizing system through a conveying pipeline, and the vertical projection of the atomizing connecting pipe on the spinneret does not contact the spinneret hole;

[0154] The number of atomizing connecting pipes, atomizing channels and atomizing nozzles is the same as the number of ring-blowing filter elements;

[0155] The cooling water pipe is connected to the ultrasonic atomization system. A cooling water solenoid valve is provided on the cooling water pipe. The cooling water solenoid valve is used to adjust the flow rate of cold water entering the ultrasonic atomization system.

[0156] The regulating valve, the pressure detector, the temperature detector and the micro pump are arranged on the delivery pipeline; the micro pump is arranged closer to the ultrasonic atomization system than the regulating valve, the pressure detector and the temperature detector; the micro pump is used to pressurize the atomization gas in the delivery pipeline;

[0157] The regulating valve, pressure detector, temperature detector and cooling water solenoid valve are all electrically connected to the PLC controller;

[0158] The temperature detector is used to detect the temperature of the atomized gas in the delivery pipeline, and send the measured temperature of the atomized gas to the PLC controller and compare it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomized gas and the set temperature exceeds 0.5°C, the PLC controller adjusts the cooling water solenoid valve to control the flow of cold water;

[0159] The regulating valve is used to adjust the pressure of the delivery pipeline;

[0160] The pressure detector is used to detect the atomizing gas pressure, and send the measured atomizing gas pressure to the PLC controller, and compare it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve;

[0161] A tension detection device is provided between the G / R1 heat roller and the G / R2 heat roller;

[0162] The process parameters include: the temperature of the spinning box is 295°C, the power of the micro-mist cooling pump is 15W, the temperature of the atomizing gas is 15°C, the pressure of the atomizing gas is 50Pa, the temperature of the annular air is 19°C, the wind speed of the annular air is 0.5m / s, the speed of the oil pump is 9.5r / min, the pre-network pressure is 0.15MPa, the speed of the G / R1 hot roller is 1900m / min, the tension of all single filaments extruded from the inner spinneret when they break is 287cN, the speed of the G / R2 hot roller is 4100m / min, and the main network pressure is 0.35MPa.

[0163] The core yarn broken fluffy polyester fiber finally obtained is a tow composed of multiple monofilaments, some of which are broken and the rest are unbroken monofilaments, the broken monofilaments are distributed on the inner side of the unbroken monofilaments, and one end of all the broken monofilaments protrudes to the outer side of the unbroken monofilaments; the fineness of the core yarn broken fluffy polyester fiber is 222.78 dtex, the total number of monofilaments is 216, the dpf is 1.031, and the number of broken monofilaments is 52% of the total number of monofilaments; the broken hairiness of the core yarn broken fluffy polyester fiber has a gradual level, the broken hairiness length is 0.2~0.6 cm, the hairiness density is 2240 filaments / m, the breaking strength is 4.12 cN / dtex, the breaking strength CV value is 2.29%, the breaking elongation is 30.9%, the breaking elongation CV value is 5.27%, the fluffiness is 86%, and the rebound rate is 91%.

Claims

1. A core yarn broken and raised polyester fiber, characterized in that: A tow composed of multiple monofilaments, a portion of which are broken, and the rest are unbroken monofilaments, the broken monofilaments are distributed inside the unbroken monofilaments, and one end of all the broken monofilaments protrudes outside the unbroken monofilaments; The fineness of the core yarn broken raised polyester fiber is 55~223dtex, the total number of monofilaments is 72~216, dpf≥0.5, and the number of broken monofilaments is 48~62% of the total number of monofilaments.

2. The core yarn broken raised polyester fiber according to claim 1, characterized in that: The breaking hair length of the core yarn broken raised polyester fiber is 0.2~0.6cm, the hair density is 880~2240 pieces / m, the breaking strength is 4.10~4.40cN / dtex, the breaking strength CV value is ≤2.90%, the breaking elongation is 28~33%, the breaking elongation CV value is ≤6.50%, the bulkiness is ≥85%, and the resilience is ≥90%.

3. The method for preparing a core yarn broken raised polyester fiber according to claim 1 or 2, characterized in that: After the polyester melt enters the spinneret for extrusion, it is sequentially cooled, oiled, pre-interlaced, G / R1 hot roller drawing, G / R2 hot roller drawing, main interlaced and wound to obtain the core yarn broken fluffy polyester fiber; The spinneret is provided with n circles of spinneret holes, n is 4 to 6, and the apertures of all the spinneret holes are the same; from the inside to the outside of the spinneret, the spinneret holes from the 1st circle to the n-1th circle or the n-2th circle are the inner spinneret holes, and the spinneret holes in the remaining circles are the outer spinneret holes; The upper surface of the spinneret is a plane, and the lower surface is provided with an arc-shaped groove, the vertical projection of the arc-shaped groove on the upper surface of the spinneret is a circle, and along the radial direction of the circle, the depth of the arc-shaped groove gradually decreases from the inside to the outside; the output end of the inner spinneret hole is located in the arc-shaped groove, and the central axis of the arc-shaped groove coincides with the central axis of the spinneret; the output end of the outer spinneret hole is located outside the arc-shaped groove; The diameter of the inner spinneret hole is 0.14-0.30 mm, the aspect ratio of the inner spinneret hole is 1.7-2.3, and the aspect ratio of the outer spinneret hole is 2.7-3.3; the total number of spinneret holes is 72-216, and the number of inner spinneret holes is 48-62% of the total number of spinneret holes; The draft ratio of the G / R1 hot roller and the G / R2 hot roller is equal to the theoretical draft ratio of the filaments extruded from the outer spinneret, and is greater than the theoretical draft ratio of the filaments extruded from the inner spinneret; the theoretical draft ratio is the draft ratio at which the filaments will not be broken at the speed of the G / R1 hot roller and the speed of the G / R2 hot roller.

4. The method for preparing a core yarn broken raised polyester fiber according to claim 3, characterized in that: The cooling is two-way mixed cooling, and the devices used for the two-way mixed cooling include a ring-blowing cooling device and a micro-mist cooling device; The circular air cooling device comprises a circular air bellows and a circular air filter element (7); the air bellows comprises a bellows housing and an upper cover plate (5); the circular air filter element (7) is arranged inside the bellows housing, and the top of the circular air filter element (7) is sealed and connected to the upper cover plate (5) via a circular air filter element sealing gasket (6); The micro-mist cooling device comprises an atomization channel (10), an atomization connecting pipe (11), an atomization nozzle (12), a cooling water pipe (13), a cooling water solenoid valve (14), a micro pump (16), a regulating valve (17), a pressure detector (18), a temperature detector (19), a PLC controller, a delivery pipeline (20) and an ultrasonic atomization system (15); The ultrasonic atomization system (15) is used to provide atomization gas; The atomizing nozzle (12) is a rod-shaped structure with a hollow interior; a plurality of spray holes are provided on the circumferential surface of the atomizing nozzle (12), and the spray holes are connected to the interior of the atomizing nozzle (12); the atomizing nozzle (12) is placed vertically and is located inside the annular air blowing bellows, and the vertical projection of the atomizing nozzle (12) on the spinneret is located inside the first circle of spinneret holes; The atomizing channel (10) is arranged inside the upper cover plate of the annular air blower, one end of the atomizing channel (10) is connected to the inside of the atomizing nozzle (12) through an atomizing connecting pipe (11), and the other end is connected to the ultrasonic atomizing system through a conveying pipe (20), and the vertical projection of the atomizing connecting pipe (11) on the spinneret does not contact the spinneret hole; The number of the atomizing connecting pipe (11), the atomizing channel (10) and the atomizing nozzle (12) is the same as the number of the ring-blowing filter element (7); The cooling water pipe (13) is connected to the ultrasonic atomization system. A cooling water solenoid valve (14) is provided on the cooling water pipe (13). The cooling water solenoid valve (14) is used to adjust the flow rate of cold water entering the ultrasonic atomization system. The regulating valve (17), the pressure detector (18), the temperature detector (19) and the micro pump (16) are arranged on the delivery pipeline (20); the micro pump (16) is arranged closer to the ultrasonic atomization system than the regulating valve (17), the pressure detector (18) and the temperature detector (19); the micro pump (16) is used to pressurize the atomization gas in the delivery pipeline (20); The regulating valve (17), the pressure detector (18), the temperature detector (19) and the cooling water solenoid valve (14) are all electrically connected to the PLC controller; The temperature detector (19) is used to detect the temperature of the atomized gas in the delivery pipeline (20), and sends the measured temperature of the atomized gas to the PLC controller and compares it with the temperature set in the PLC controller. When the absolute value of the difference between the measured temperature of the atomized gas and the set temperature exceeds 0.5° C., the PLC controller adjusts the cooling water solenoid valve (14) to control the flow rate of cold water; The regulating valve (17) is used to adjust the pressure of the delivery pipeline (20); The pressure detector (18) is used to detect the atomizing gas pressure, and sends the measured atomizing gas pressure to the PLC controller and compares it with the pressure set in the PLC controller. When the absolute value of the difference between the measured atomizing gas pressure and the set pressure exceeds 5% of the set value, the PLC controller adjusts the regulating valve (17).

5. The method for preparing a core yarn broken raised polyester fiber according to claim 4, characterized in that: A tension detection device is provided between the G / R1 heat roller and the G / R2 heat roller.

6. The method for preparing a core yarn broken raised polyester fiber according to claim 5, characterized in that: The process parameters include: the temperature of the spinning box is 280~295℃, the power of the micro-mist cooling pump is 10~15W, the temperature of the atomizing gas is 15~19℃, the pressure of the atomizing gas is 30~50Pa, the temperature of the annular air is 19~22℃, the wind speed of the annular air is 0.2~0.5m / s, the pre-network pressure is 0.10~0.15MPa, the speed of the G / R1 hot roller is 1900~2200m / min, the tension is 84~290cN, the speed of the G / R2 hot roller is 3900~4200m / min, and the main network pressure is 0.25~0.35MPa.

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