CN116377631B

CN116377631B - Preparation method of micro-fine denier polyester filament yarn

Info

Publication number: CN116377631B
Application number: CN202310650922.6A
Authority: CN
Inventors: 赵金广; 郭振军; 倪凤军; 郭皎; 赵慧娟
Original assignee: Jiangsu Deli Chemical Fiber Co Ltd
Current assignee: Jiangsu Deli Chemical Fiber Co Ltd
Priority date: 2023-06-05
Filing date: 2023-06-05
Publication date: 2023-08-29
Anticipated expiration: 2043-06-05
Also published as: CN116377631A

Abstract

The invention belongs to the technical field of textile fabrics, and relates to a preparation method of a micro fine denier polyester filament yarn, which takes polyester POY as a raw material and adopts a DTY process to prepare the micro fine denier polyester filament yarn; the first deformation hot box is a double semicircular open-close hot box; the middle network device adopts a network nozzle with a round table-shaped hole; when the silk strip just enters the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 70-80 degrees; when the yarn just exits the yarn running channel, the moving direction of the yarn and the air flow direction of the network nozzle form an angle of 100-110 degrees; the oil tanker wire guide adopts a double-rotation oil tanker wire guide; the cooling device adopts a spiral hollow air cooling device; the method disclosed by the invention is simple in preparation, optimizes the process equipment in the prior art, and can be used for preparing the micro fine denier polyester filament yarn with stable performance indexes.

Description

Preparation method of micro-fine denier polyester filament yarn

Technical Field

The invention belongs to the technical field of textile fabrics, and relates to a preparation method of micro fine denier polyester filaments.

Background

Along with the continuous improvement of the living standard of people, the requirements of people on the diversity, the comfort and the functionality of the clothing are also becoming wider and wider. The fiber fine denier and the functionalization are an important direction for the development of differential fibers and are also the main development trend of polyester fiber spinning. The fabric processed by the polyester conventional variety has limitation on air permeability, functionality and the like. The fiber with smaller single-filament fineness is called microfiber, the fiber is finer to a certain degree, a plurality of new characteristics can be exerted, and the terylene microfiber fine denier terylene fiber has finer filaments, large bending strength and very good softness and air permeability of the woven cloth cover, light and thin fabric and is very comfortable to wear due to the unique characteristics of the fiber.

The bus density of the micro fine denier fiber is about 5-10D, the bus density is low, the processing difficulty is high, the resistance to the filament caused by contact of the filament with equipment such as a hot box, a yarn guide, a cooling device, a network nozzle and the like in the processing process is likely to damage the filament bundle, break the filament, even cause broken ends, dye and stretch problems caused by uneven heating and cooling, the problem of difficulty in producing micro fiber is also solved, and the performance index is unstable, so that the back textile fabric is easy to generate transverse strips, unreeled and the like.

Patent application number CN03111978.6 discloses a preparation method of superfine double-shrinkage fiber false-twist composite yarn, and a composite yarn is produced. The patent with publication number CN111676558A discloses a production process of superfine denier polyester DTY, the heating and cooling of a deformation hot box are all in contact, friction resistance generated by contact of the equipment and silk in actual production can cause serious influence on stable production of microfiber, the breakage rate and the filigree rate are obviously increased, and the cooling effect is not good, but no solution is given.

Therefore, the research of the preparation method of the micro fine denier polyester filament with stable performance index has very important significance.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a preparation method of a micro fine denier polyester filament yarn.

In order to achieve the above purpose, the invention adopts the following scheme:

a preparation method of a fine denier polyester filament yarn uses polyester POY as a raw material and adopts a DTY process to prepare the fine denier polyester filament yarn;

the DTY process flow comprises the following steps: polyester POY- & gt pre-networking- & gt first yarn feeding roller- & gt first deformation hot box- & gt cooling device- & gt false twister- & gt second yarn feeding roller- & gt middle networking- & gt second shaping hot box- & gt shaping overfeeding roller- & gt yarn detector- & gt oiling wheel- & gt oil wheel yarn guide- & gt winding and forming;

the bus density of the microfiber is about 5-10D, the bus density is low, the processing difficulty is high, the resistance to the filament caused by the contact of the filament with equipment such as a hot box, a yarn guide, a cooling device, a network nozzle and the like in the processing process is likely to damage the filament bundle, break the filament, even cause broken ends, and the dyeing and stretching problems caused by uneven heating and cooling are also the difficulty in producing microfiber. Specifically:

The first deformation hot box is a double semicircular open-close hot box, is a circular hot box formed by closing two semicircular hot boxes with the same size, forms two joints, uses a bolt at one joint to connect the two semicircular hot boxes, and uses the bolt as an axis to realize the opening and closing of the hot boxes; a plurality of heating pipes are uniformly and parallelly distributed in the first deformation hot box;

the silk thread passes through the center of the double semicircular open-close type heat box, has the same distance with the heating pipe, is heated more uniformly, and improves the dyeing uniformity by 10% relative to the contact type heat box; the situation that the friction is increased by adopting direct contact due to thin yarn strips, and meanwhile, the contact surface is heated more than the non-contact surface, so that the stretching deformation is influenced is avoided;

the middle network device adopts a network nozzle with a round table-shaped hole; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk-running channel, the included angle between the silk strip and the silk-running channel is 15 degrees, and the angle between the movement direction of the silk strip and the airflow direction of the network nozzle is 70-80 degrees; when the silk strip just leaves the silk channel, the included angle between the silk strip and the silk channel is 15 degrees, the angle between the movement direction of the silk strip and the air flow direction of the network nozzle is 100-110 degrees, and the angle is designed in the range, so that the silk strip is tensioned in the silk channel to form a network point conveniently, meanwhile, the friction force between the silk strip and the silk guide of the silk channel is reduced, and the air flow reaches the small diameter through the large diameter of the truncated cone-shaped network nozzle, so that the air flow is sprayed onto the silk strip to form a node. Because the silk is thinner, the network nozzle with the truncated cone shape is adopted to ensure that the air flow is more concentrated in the running process, thereby ensuring the definition of the micro fiber network;

The oil tanker wire guide adopts a double-rotation oil tanker wire guide; the double-rotation oil tanker silk guide comprises a groove silk guide, a silk guide support, a main shaft, a main bearing, an anti-slip silk ring, a spacer ring, a nut and a gasket; one end of the main shaft is fixedly connected with the inner ring of the main bearing; the other end of the main shaft sequentially passes through the anti-slip wire ring, the spacing ring, the oil frame, the gasket and the nut, and the main shaft is fixed on the oil frame by the nut;

the wire guide bracket is of a cylindrical structure; along the height direction of the cylinder, the cylinder is penetrated by a round hole; the round holes comprise a large round hole and a small round hole I; the central axis of the large round hole is coincident with the central axis of the cylinder, and the small round holes I are uniformly distributed around the central axis of the cylinder and are arranged on the periphery of the large round hole; the periphery of the cylinder is provided with small round holes II, the number of the small round holes II is the same as that of the small round holes I, and each small round hole II is respectively communicated with one small round hole I;

the wire guide bracket is fixed on the outer ring of the main bearing through a large round hole; the bottom of the groove wire guide is provided with a bearing, and the bottom of the bearing is provided with a bearing seat; the bearing seat is arranged in the small round hole I through the small round hole II, and a shaft sequentially passes through one end of the small round hole I, the bearing seat and the other end of the small round hole I to fix the groove wire guide on the wire guide bracket;

When the silk strip passes through the rotary silk guide, the main bearing rotates, and the groove-shaped silk guide is driven by the main bearing to rotate, so that the silk strip can rotate in double directions;

when the silk strip passes through the groove-shaped silk guide, the silk strip is in point contact with the silk guide, compared with the silk guide, the surface contact surface is reduced, the contact surface is small, and the friction resistance is smaller due to double rotation. Compared with the existing rotary yarn guide, the problem of resistance increase caused by large contact area and large running angle when the micro fine denier fiber passes through the oil wheel yarn guide due to small winding tension is solved, so that the yarn breakage rate of yarn throwing is reduced to 3% from 10% at the same time, and the yarn breakage rate is reduced to no yarn at the same time from 3% at the original yarn breakage rate;

the cooling device adopts a spiral hollow air cooling device and consists of an inner cylinder and an outer cylinder with different diameters, the area between the inner cylinder and the outer cylinder is sealed up and down, the inner cylinder is not sealed up and down, a strand silk passes through the middle of the inner cylinder, a hollow circular cooling pipe is spirally wound in a sealed space, and an opening is respectively arranged at the upper part and the lower part of the sealed space and is respectively connected with two ends of the hollow circular cooling pipe, one is an inlet, and the other is an outlet;

the cooling device in the prior art generally adopts a cooling plate, and the air contact type cooling is adopted, so that the cooling effect is influenced by the ambient temperature; the spiral hollow air cooling device is adopted to cool the micro fine denier polyester filament, the filament is not in direct contact with the cooling device and the cooling air, the cold air cools the periphery through the spiral hollow cooling pipe, and further the filament is cooled (the cooling is the temperature of the cold air), so that uneven cooling effects of the inner layer and the outer layer caused by direct contact of the cooling air are avoided, uneven cooling effects of the contact surface and the non-contact surface caused by direct contact of the cooling air with the cooling device are avoided, the device can cool the filament by changing the cooling air quantity of the hollow cooling pipe, the cooling effect is obvious, and the stretching effect is better.

As a preferable technical scheme:

according to the preparation method of the micro fine denier polyester filament yarn, the diameter of the small opening of the truncated cone-shaped network nozzle is 0.8+/-0.05 mm, and the diameter of the large opening is 1.2+/-0.05 mm.

The preparation method of the micro fine denier polyester filament yarn has the advantages that the diameter of the inner cylinder is 5cm, and the diameter of the outer cylinder is 8cm.

According to the preparation method of the micro fine denier polyester filament yarn, the false twister adopts the ceramic disc, the polyurethane disc and the knife edge disc in a 1-2-1 combination mode, and the hardness of the polyurethane disc is 86A/D. The combination in the existing device is basically 1-5-1 and 1-4-1, and the invention adopts a mode that the combination 1-2-1 is a ceramic disc 1, a polyurethane disc 2 and a knife edge disc 1 in sequence. The polyurethane disc has a specification of 52mm diameter, 8.6mm thickness and 86A/D hardness. Low disc combination, low hardness, reduced friction damage to the yarn, reduced broken yarn, and maintained strength. Meanwhile, the problem that the false twister causes difficulty in spinning up due to small untwisting tension can be avoided, and the tight point of the finished yarn is well solved.

According to the preparation method of the micro fine denier polyester filament yarn, the breaking elongation of the polyester POY is 115%, the breaking strength is 2.8cN/dtex, and the thermal stress is 16cN.

According to the preparation method of the micro fine denier polyester filament yarn, the pre-network air pressure is 0.03-0.05 MPa, and the medium-network air pressure is 0.05-0.12 MPa.

According to the preparation method of the micro fine denier polyester filaments, the temperature of the first deformation hot box is 160-170 ℃; the temperature of the second shaping hot box is 130-140 ℃; the cooling temperature is 20-25 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller, namely the draft multiple is 1.5-1.6; the speed ratio of the false twister (the ratio of the surface rotating speed of the polyurethane disc to the speed of the second wire feeding roller) is 1.6-1.7; the processing speed of the second wire feeding roller is 500-600 m/min; the overfeeding rate of the shaping overfeeding roller is-6.0 to-5.5 percent.

In the prior art, the temperature of a first deformation hot box is generally higher than 170 ℃, the temperature of a second shaping hot box is higher than 140 ℃, the draft multiple is 1.65-1.75, and the processing speed of a second wire feeding roller is 600-800 m/min;

the first deformation hot box has the functions that: the POY precursor is heated and softened, the rigidity of the POY precursor is weakened, the plasticity is enhanced, and the drawing is facilitated. The temperature of the first deformation heat box is too high, so that POY precursor wires are bonded, false twisting is incomplete in a false twisting deformation process, tight points and stiff wires are generated, molecules in the POY precursor wires are oxidized, the strength and elongation are reduced, broken wires are generated, and the broken wire rate is increased; the temperature of the first deformation hot box is too low to reach the softening point of the silk, the silk is subjected to cold stretching, the stretching uniformity is poor, and the dyeing rate is low.

The second shaping hot box has the functions that: by controlling the temperature, the overall orientation degree and crystallinity of the fiber are improved, and the stress in the fiber is eliminated, so that the thermal stability of the fiber is remarkably improved. The setting temperature is too low, so that the internal stress of the fiber cannot be eliminated, and the structural stability is poor; when the shaping temperature is too high, the rolling rate of the finished product silk is too low, and the woven cloth surface has the conditions of hard hand feeling and softness.

The second yarn feeding roller has the advantages of too high processing speed, reduced running stability of yarn, increased broken ends, too low speed and low efficiency.

The draft multiple is too high, filaments of the silk filament are broken to generate a broken silk, and the strength and the extensibility are reduced; too small draft ratio, unstable system, and the color difference of the sock after dyeing.

According to the preparation method of the micro fine denier polyester filament yarn, the oiling rate is 2.8-3.0%, so that the cohesive force of the filament yarn is increased, and the filament yarn is ensured not to be thrown at the sizing overfeeding position in the winding process.

The preparation method of the micro fine denier polyester filament yarn, wherein the total fineness of the micro fine denier polyester filament yarn is 5.5-10.8 dtex, the elongation at break is 22.3-24%, the breaking strength is 4.0-4.15 cN/dtex, the network point uniformity is more than or equal to 98%, the breaking rate is less than or equal to 2%, the elongation at break variation coefficient (CV value) is 4.0-5.0%, and the on-line tension coefficient (CV value) is 1.3-1.4%; according to the polyester low stretch yarn GB/T14460-2015, the elongation at break variation coefficient (CV value) is obtained by stretching a 500mm long yarn with a pretension of 0.2 cN by a stretching instrument, wherein the elongation at break is obtained by increasing the ratio of the length of the yarn to the original length when the yarn breaks, and all elongation at break data are obtained after multiple measurements, and the degree of dispersion of the data is the elongation at break variation coefficient (CV value); the online tension coefficient (CV value) is the discrete degree of online tension in the production of the silk yarn, and the equipment is provided with an online tension detection device; DTY appearance evaluation: no hairline, stumbling and tight spots; the rear textile has few broken ends and good cloth cover without cross bars.

Advantageous effects

(1) According to the preparation method of the micro fine denier polyester filament yarn, the combination of the discs is changed, and a combination mode of 1-2-1 is adopted, so that the yarn is more smooth in head generation, and the tight point of a finished yarn is well solved;

(2) According to the preparation method of the micro fine denier polyester filament, the network nozzle with the circular truncated cone-shaped holes is adopted, so that network points are more uniform and clear;

(3) According to the preparation method of the micro fine denier polyester filament, the double-rotation type oil tanker yarn guide device is adopted, so that yarn throwing broken ends and broken filaments caused by high yarn running resistance are reduced;

(4) The invention relates to a preparation method of micro fine denier polyester filament yarn, which adopts a double semicircular closed type hot box with heating pipes uniformly and parallelly distributed on the inner wall; the yarn is not contacted with the hot box, so that the yarn is heated more uniformly, and the dyeing uniformity is improved;

(5) The invention relates to a preparation method of micro fine denier polyester filaments, which adopts a spiral hollow air cooling device; the silk thread is not contacted with the cooling device, and cold air passes through the spiral hollow cold pipe, and the temperature of the hollow cold pipe is changed, so that the silk thread is cooled, the cooling effect is obvious, and the stretching effect is better.

Drawings

FIG. 1 is a schematic illustration of a process flow of the present application;

FIG. 2 is a front view of a dual rotary tanker wire guide;

FIG. 3 is a side view of a dual rotary tanker wire guide;

FIG. 4 is a front view of a frustoconical nozzle orifice;

FIG. 5 is a side view of a frustoconical nozzle orifice;

FIG. 6 is a schematic diagram of a false twister assembly;

FIG. 7 is a top view of a double semi-circular open and closed hot box;

FIG. 8 is a front view of a double semi-circular open and closed hot box;

FIG. 9 is a top view of a helical hollow air-cooling device;

FIG. 10 is a three-dimensional view of a helical hollow air-cooling device;

FIG. 11 is a schematic view of a threadline passing through a mid-network;

the device comprises a 1-polyester POY, a 2-pre-network, a 3-first wire feeding roller, a 4-first deformation hot box, a 5-cooling device, a 6-false twister, a 7-second wire feeding roller, an 8-medium network device, a 9-second shaping hot box, a 10-shaping overfeeding roller, a 11-wire detector, a 12-oiling wheel, a 13-oil wheel wire guide device, a 14-winding device, a 15-gasket, a 16-main shaft, a 17-anti-skid wire ring, a 18-groove wire guide device, a 19-wire guide device bracket, a 20-spacer ring, a 21-nut, a 22-ceramic disc, a 23-polyurethane disc and a 24-knife edge disc.

Detailed Description

The application is further described below in conjunction with the detailed description. It is to be understood that these examples are illustrative of the present application and are not intended to limit the scope of the present application. Furthermore, it should be understood that various changes and modifications can be made by one skilled in the art after reading the teachings of the present application, and such equivalents are intended to fall within the scope of the application as defined in the appended claims.

The test method related in the specific embodiment is as follows:

elongation at break, breaking strength: referring to the GB/T14460-2015 test standard, fixing the yarn thread end on a length measuring instrument, setting the winding circle number to be 100 (1 circle = 1 meter), starting a switch, and after the yarn is wound by 100 circles; taking down the yarn, connecting the yarn end with a stretching tester, opening a testing program, setting the pretension to be 0.2cN, setting the speed to be 350mm/min, and carrying out automatic test on the breaking strength and the breaking elongation with the clamping length of 500 mm;

network point uniformity: referring to GB/T14460-2015 test standard, taking 1m long yarn, counting the number of network points to obtain network degree, measuring the minimum distance between the network points, calculating the theoretical networking number of the 1m yarn, and obtaining the network uniformity by the actual network number/theoretical network number.

Wire breakage rate: the number of broken wires per total ingot per machine in the process of completing one weight fixing is 288.

Dyeing M ratio: referring to GB/T14460-2015 test standard, after the yarn cylinder textile sock is dyed, the yarn cylinder number/yarn cylinder total number of the yarn cylinder textile sock which is inconsistent with the standard color is 288.

Example 1

The preparation method of the micro fine denier polyester filament yarn comprises the following specific processes:

Using polyester POY 1 as a raw material, and adopting a DTY process to prepare micro fine denier polyester filament yarns;

wherein, the specification of the terylene POY 1 is 12dtex/7f, the elongation at break is 115 percent, the breaking strength is 2.8cN/dtex, and the thermal stress is 16cN;

as shown in fig. 1, the DTY process flow includes: polyester POY 1, pre-net 2, first yarn feeding roller 3, first deformation hot box 4, cooling device 5, false twister 6, second yarn feeding roller 7, middle net, second shaping hot box 9, shaping overfeeding roller 10, yarn detector 11, oil feeding wheel 12, oil wheel yarn guide 13 and winding forming;

the devices used in the DTY process flow comprise a first deformation hot box 4, a cooling device 5, a false twister 6, a middle network device 8, a tanker wire guide 13 and a winding device 14;

as shown in fig. 7 and 8, the first deformation hot box 4 is a double semicircular open and closed hot box, and is a circular hot box formed by closing two semicircular hot boxes with the same size; a plurality of heating pipes are uniformly and parallelly distributed in the first deformation heat box 4;

as shown in fig. 9 and 10, the cooling device 5 adopts a spiral hollow air cooling device, and consists of an inner hollow cylinder and an outer hollow cylinder with different diameters, wherein the diameter of the inner cylinder is 5cm, and the diameter of the outer cylinder is 8cm; the area between the inner cylinder and the outer cylinder is sealed up and down, the inner cylinder is not sealed up and down, the thread strip passes through the middle of the inner cylinder, the hollow circular cold pipe is spirally wound in the sealed space, and the sealed space is provided with an opening at the upper part and the lower part respectively, and the opening is respectively connected with two ends of the hollow circular cold pipe, one is an inlet and the other is an outlet;

As shown in FIG. 6, the false twister 6 adopts a combination mode of a ceramic disc 22, a polyurethane disc 23 and a knife edge disc 24 in a mode of 1-2-1, wherein the hardness of the polyurethane disc 23 is 86A/D;

as shown in fig. 4 and 5, the middle network device 8 adopts a network nozzle with a circular truncated cone-shaped hole, wherein the diameter of a small opening of the circular truncated cone-shaped network nozzle is 0.8mm, and the diameter of a large opening of the circular truncated cone-shaped network nozzle is 1.2mm; as shown in fig. 11, the included angle between the moving direction of the yarn in the yarn path on the middle net device 8 and the central axis of the circular truncated cone-shaped net nozzle is 90 degrees; when the silk strip just enters the silk feeding channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 70 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 110 degrees;

as shown in fig. 2 and 3, the oil tanker wire guide 13 adopts a double-rotation oil tanker wire guide; the double-rotation oil tanker silk guide comprises a groove silk guide 18, a silk guide bracket 19, a main shaft 16, a main bearing, an anti-slip silk ring 17, a spacing ring 20, a nut 21 and a gasket 15; one end of the main shaft 16 is fixedly connected with the inner ring of the main bearing; the other end of the main shaft 16 sequentially passes through the anti-slip wire ring 17, the space ring 20, the oil frame, the gasket 15 and the nut 21, and the main shaft 16 is fixed on the oil frame by the nut 21;

The wire guide bracket 19 is of a cylindrical structure; along the height direction of the cylinder, the cylinder is penetrated by a round hole; the round holes comprise a large round hole and a small round hole I; the central axis of the large round hole is coincident with the central axis of the cylinder, the small round holes I are uniformly distributed around the central axis of the cylinder and are arranged on the periphery of the large round hole, the number of the small round holes II is the same as that of the small round holes I, and each small round hole II is communicated with one small round hole I;

the wire guide bracket 19 is fixed on the outer ring of the main bearing through a large round hole; the bottom of the groove wire guide 18 is provided with a bearing, and the bottom of the bearing is provided with a bearing seat; the bearing seat is arranged in the small round hole I through the small round hole II, and a shaft sequentially passes through one end of the small round hole I, the bearing seat and the other end of the small round hole I to fix the groove wire guide 18 on the wire guide bracket 19;

the technological parameters involved in the technological process are as follows: the air pressure of the pre-network 2 is 0.05MPa, and the air pressure of the middle network 8 is 0.12MPa; the temperature of the first deformation hot box 4 is 165 ℃; the temperature of the second shaping hot box 9 is 130 ℃; the cooling temperature is 20 ℃; the ratio of the speed of the second wire feeding roller 7 to the speed of the first deformation hot box 4 is 1.5; the speed ratio of the false twister 6 is 1.6; the processing speed of the second wire feeding roller 7 is 500 m/min; the overfeed rate of the yarn detector 11 was-5.5%.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.5dtex, the elongation at break is 24%, the breaking strength is 4cN/dtex, the evenness of network points is 98.6%, the breaking rate is 1.4%, the elongation at break variation coefficient is 5%, the on-line tension coefficient is 1.4%, the oiling rate is 2.86%, the dyeing M rate (qualification rate) is 99.4%, the appearance is free of broken filaments, stumbled filaments and tight points, and after spinning, broken ends are few, the cloth cover is good and no cross bars exist.

Comparative example 1

A method for preparing micro fine denier polyester filament yarn is basically the same as that of example 1, except that a common rotary oil tanker silk guide (manufacturer is basic overflow) is adopted as the oil tanker silk guide.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.64dtex, the elongation at break is 19.2%, the breaking strength is 3.85cN/dtex, the uniformity of network points is 98.3%, the breaking rate is 10%, the elongation at break variation coefficient is 8.8%, the on-line tension coefficient is 1.32%, the oiling rate is 2.8%, and the hairline rate is 3%.

The elongation at break and the breaking strength of comparative example 1 were reduced and the elongation at break, the coefficient of variation at break and the yarn breakage were increased as compared with example 1, because the comparative example 1 uses a conventional rotary tanker yarn guide, the contact surface between the yarn and the yarn guide was large, the resistance to the yarn was relatively large, the elongation at break and the breaking strength were reduced due to the breakage of the monofilament, and the yarn breakage, the coefficient of variation at break and the yarn breakage were increased.

Comparative example 2

A preparation method of micro-fine denier polyester filament yarn is basically the same as that of the embodiment 1, except that a false twister adopts a combination mode of a ceramic disc, a polyurethane disc and a knife edge disc in a mode of 1-4-1.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.6dtex, the elongation at break is 20.2%, the breaking strength is 3.9cN/dtex, the uniformity of network points is 98.3%, the yarn breaking rate is 8.2%, the elongation at break variation coefficient is 7.2%, the on-line tension coefficient is 1.42%, the oiling rate is 2.9%, the appearance is tight, and the manufactured fabric surface is provided with transverse strips.

The elongation at break and the breaking strength of comparative example 2 were reduced and the elongation at break and the coefficient of variation of the elongation at break were increased as compared with example 1, because the comparative example 2 uses a combination of 1 to 4 to 1, which increases the frictional damage to polyester POY and breaks the filaments of the yarn, resulting in a decrease in the related index.

Comparative example 3

A preparation method of a micro-fine denier polyester filament yarn is basically the same as that of the embodiment 1, and only the difference is that a network nozzle with a cylindrical hole shape is adopted as a network device in the comparative embodiment 3, and the inner diameter is the same as the large opening diameter of a truncated cone-shaped network nozzle in the embodiment 1.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.6dtex, the elongation at break is 19.4%, the breaking strength is 3.93cN/dtex, the network point uniformity is 85.4%, the yarn breaking rate is 2.0%, the elongation at break variation coefficient is 4.8%, the on-line tension coefficient is 1.3%, and the oil application rate is 2.88%.

The elongation at break, breaking strength, and network uniformity of comparative example 3 were reduced as compared with example 1, because the network nozzle aperture of comparative example 3 was large, resulting in a decrease in network uniformity, a decrease in filament cohesion, and a decrease in elongation at break and breaking strength.

Comparative example 4

A method for preparing micro-fine denier polyester filaments, which is basically the same as that of example 1, except that the first deformation hot box is a conventional contact hot box (pamag, high temperature hot box).

The total fineness of the prepared micro fine denier polyester filament yarn is 7.7dtex, the elongation at break is 20.8%, the breaking strength is 3.97cN/dtex, the uniformity of network points is 98.2%, the breaking rate is 4.2%, the elongation at break variation coefficient is 12.0%, the on-line tension coefficient is 1.8%, the oiling rate is 2.82%, and the dyeing M rate (qualification rate) is 88%.

The elongation at break, the breaking strength, the dyeing M-rate were decreased, the yarn breakage rate, the elongation at break variation coefficient, and the on-line tension coefficient were increased as compared with example 1, because the first deforming hot box in comparative example 4 was in contact, the yarn was heated unevenly, and the stretching deformation uniformity was poor, resulting in a low dyeing M-rate.

Comparative example 5

A method for preparing micro fine denier polyester filaments is basically the same as in example 1, except that the cooling device is a conventional cold plate (Bama lattice, V-shaped cooling plate) with contact cooling.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.68dtex, the elongation at break is 20.4%, the breaking strength is 3.98cN/dtex, the network point uniformity is 98.1%, the yarn breaking rate is 4.0%, the elongation at break variation coefficient is 10.5%, the on-line tension coefficient is 1.6%, and the oil application rate is 2.9%.

The elongation at break, the breaking strength, the coefficient of variation of elongation at break, and the coefficient of online tension of comparative example 5 were decreased as compared with example 1, because the conventional cold plate used in comparative example 5 was cooled in contact, the contact surface of the yarn was different from the cooling effect of the non-contact surface, the effect of stretching deformation was affected, and the stretching was uneven and unstable.

Comparative example 6

The preparation method of the micro fine denier polyester filament yarn is basically the same as that of the embodiment 1, except that the movement direction of the filament yarn is 45 degrees with the air flow direction of the network nozzle when the filament yarn just enters the filament-moving channel; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 135 degrees.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.62dtex, the elongation at break is 21.4%, the breaking strength is 3.96cN/dtex, the uniformity of network points is 97.5%, the breaking rate is 2.0%, the elongation at break variation coefficient is 5.3%, the on-line tension coefficient is 1.35%, the oil application rate is 2.95%, and the hairline rate is 1.5%.

The elongation at break and the breaking strength of comparative example 6 were reduced and the coefficient of variation at break and the yarn breakage rate were increased as compared with example 1, because the yarn of comparative example 6 was reduced in the direction of movement of the yarn at an angle to the air flow direction of the net nozzle immediately after entering the yarn passage, and the direction of movement of the yarn was increased in the direction of movement of the yarn at an angle to the air flow direction of the net nozzle immediately after exiting the yarn passage, resulting in an increase in friction between the yarn and the nozzle yarn guide, and the filaments were easily broken and the net point was easily pulled apart.

Example 2

using polyester POY as a raw material, and adopting a DTY process to prepare micro fine denier polyester filament yarns;

wherein, the specification of the terylene POY is 12dtex/7f, the elongation at break is 115%, the breaking strength is 2.8cN/dtex, and the thermal stress is 16cN;

the device used in the DTY process flow comprises a first deformation hot box, a cooling device, a false twister, a medium network device, a tanker wire guide device and a winding device;

The first deformation hot box is a double semicircular open-close hot box and is a circular hot box formed by closing two semicircular hot boxes with the same size; a plurality of heating pipes are uniformly and parallelly distributed in the first deformation hot box;

the cooling device adopts a spiral hollow air cooling device and consists of an inner cylinder and an outer cylinder with different diameters, wherein the diameter of the inner cylinder is 5cm, and the diameter of the outer cylinder is 8cm; the area between the inner cylinder and the outer cylinder is sealed up and down, the inner cylinder is not sealed up and down, the thread strip passes through the middle of the inner cylinder, the hollow circular cold pipe is spirally wound in the sealed space, and the sealed space is provided with an opening at the upper part and the lower part respectively, and the opening is respectively connected with two ends of the hollow circular cold pipe, one is an inlet and the other is an outlet;

the false twister adopts a combination mode of a ceramic disc, a polyurethane disc and a knife edge disc in a mode of 1-2-1, and the hardness of the polyurethane disc is 86A/D;

the middle network device adopts a network nozzle with a hole shape of a truncated cone, the diameter of a small opening of the network nozzle with the truncated cone is 0.8mm, and the diameter of a large opening of the network nozzle with the truncated cone is 1.2mm; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk feeding channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 70 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 100 degrees;

the wire guide bracket is of a cylindrical structure; along the height direction of the cylinder, the cylinder is penetrated by a round hole; the round holes comprise a large round hole and a small round hole I; the central axis of the large round hole is coincident with the central axis of the cylinder, the small round holes I are uniformly distributed around the central axis of the cylinder and are arranged on the periphery of the large round hole, the number of the small round holes II is the same as that of the small round holes I, and each small round hole II is communicated with one small round hole I;

The technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.03MPa, and the medium-network air pressure is 0.05MPa; the temperature of the first deformation hot box is 160 ℃; the temperature of the second shaping hot box is 132 ℃; the cooling temperature is 21 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller is 1.53; the false twister speed ratio was 1.62; the second wire feeding roller has a processing speed of 520 m/min; the overfeeding rate of the shaping overfeeding roller is-5.6 percent.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.66dtex, the elongation at break is 23.5%, the breaking strength is 4.03cN/dtex, the evenness of a network point is 98.5%, the breaking rate is 1.4%, the elongation at break variation coefficient is 4.6%, the on-line tension coefficient is 1.36%, the oiling rate is 2.86%, the dyeing M rate (qualification rate) is 99.2%, the appearance is free of broken filaments, stumbled filaments and tight spots, and after-spinning broken ends are few, the cloth cover is good and no cross bar exists.

Example 3

the middle network device adopts a network nozzle with a hole shape of a truncated cone, the diameter of a small opening of the network nozzle with the truncated cone is 0.8mm, and the diameter of a large opening of the network nozzle with the truncated cone is 1.2mm; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk feeding channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 73 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 102 degrees;

the technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.03MPa, and the medium-network air pressure is 0.07MPa; the temperature of the first deformation hot box is 162 ℃; the temperature of the second shaping hot box is 134 ℃; the cooling temperature is 22 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller is 1.55; the false twister speed ratio is 1.64; the processing speed of the second wire feeding roller is 540 m/min; the overfeeding rate of the shaping overfeeding roller is-5.7 percent.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.62dtex, the elongation at break is 23.2%, the breaking strength is 4.05cN/dtex, the uniformity of network points is 98.4%, the yarn breaking rate is 1.6%, the elongation at break variation coefficient is 4.5%, the on-line tension coefficient is 1.32%, the oiling rate is 2.94%, the dyeing M rate (qualification rate) is 99.3%, the appearance is free of broken filaments, stumbled filaments and tight points, and after-spinning broken ends are few, the cloth cover is good and no cross bar exists.

Example 4

the middle network device adopts a network nozzle with a hole shape of a truncated cone, the diameter of a small opening of the network nozzle with the truncated cone is 0.8mm, and the diameter of a large opening of the network nozzle with the truncated cone is 1.2mm; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk feeding channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 76 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 105 degrees;

the technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.04MPa, and the medium-network air pressure is 0.09MPa; the temperature of the first deformation hot box is 164 ℃; the temperature of the second shaping hot box is 136 ℃; the cooling temperature is 23 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller is 1.57; the false twister speed ratio was 1.66; the second wire feeding roller has a processing speed of 560 meters/min; the overfeeding rate of the shaping overfeeding roller is-5.8%.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.58dtex, the elongation at break is 22.9%, the breaking strength is 4.08cN/dtex, the uniformity of network points is 98.6%, the yarn breaking rate is 1.6%, the elongation at break variation coefficient is 4.5%, the on-line tension coefficient is 1.3%, the oiling rate is 3%, the dyeing M rate (qualification rate) is 99.4%, the appearance is free of broken filaments, stumbled filaments and tight points, and after-spinning broken ends are few, the cloth cover is good and no cross bars are formed.

Example 5

the middle network device adopts a network nozzle with a hole shape of a truncated cone, the diameter of a small opening of the network nozzle with the truncated cone is 0.75mm, and the diameter of a large opening of the network nozzle with the truncated cone is 1.15mm; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk feeding channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 78 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 107 degrees;

the technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.04MPa, and the medium-network air pressure is 0.1MPa; the temperature of the first deformation hot box is 168 ℃; the temperature of the second shaping hot box is 138 ℃; the cooling temperature is 24 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller is 1.59; the false twister speed ratio was 1.68; the processing speed of the second wire feeding roller is 580 m/min; the overfeeding rate of the shaping overfeeding roller is-5.9%.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.53dtex, the elongation at break is 22.5%, the breaking strength is 4.08cN/dtex, the uniformity of network points is 98.5%, the yarn breaking rate is 1.8%, the elongation at break variation coefficient is 4%, the on-line tension coefficient is 1.32%, the oiling rate is 2.93%, the dyeing M rate (qualification rate) is 99.5%, the appearance is free of broken filaments, stumbled filaments and tight points, and after-spinning broken ends are few, the cloth cover is good and no cross bars are formed.

Example 6

the middle network device adopts a network nozzle with a hole shape of a truncated cone, the diameter of a small opening of the network nozzle with the truncated cone is 0.85mm, and the diameter of a large opening of the network nozzle with the truncated cone is 1.25 mm; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 80 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 110 degrees;

the technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.05MPa, and the medium-network air pressure is 0.12MPa; the temperature of the first deformation hot box is 170 ℃; the temperature of the second shaping hot box is 140 ℃; the cooling temperature is 25 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller is 1.6; the false twister speed ratio is 1.7; the second wire feeding roller has a processing speed of 600 meters/min; the overfeeding rate of the shaping overfeeding roller is-6%.

The total fineness of the prepared micro fine denier polyester filament yarn is 7.5dtex, the elongation at break is 22.3%, the breaking strength is 4.15cN/dtex, the uniformity of network points is 98.7%, the yarn breaking rate is 2%, the elongation at break variation coefficient is 4.2%, the on-line tension coefficient is 1.3%, the oiling rate is 2.8%, the dyeing M rate (qualification rate) is 99.4%, the appearance is free of broken filaments, stumbled filaments and tight points, and after-spinning broken ends are few, the cloth cover is good and no cross bars are formed.

Example 7

wherein, the specification of the terylene POY is 8dtex/5f, the elongation at break is 110 percent, the breaking strength is 2.8cN/dtex, and the thermal stress is 12.5cN;

the middle network device adopts a network nozzle with a hole shape of a truncated cone, the diameter of a small opening of the network nozzle with the truncated cone is 0.8mm, and the diameter of a large opening of the network nozzle with the truncated cone is 1.2mm; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk feeding channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 70 degrees; when the silk strip just exits the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 110 degrees;

the technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.03MPa, and the medium-network air pressure is 0.10MPa; the temperature of the first deformation hot box is 162 ℃; the temperature of the second shaping hot box is 130 ℃; the cooling temperature is 20 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first deformation hot box is 1.52; the false twister speed ratio was 1.63; the processing speed of the second wire feeding roller is 500 m/min; the overfeed rate of the yarn detector is-5.54%.

The total fineness of the prepared micro fine denier polyester filament yarn is 5.5dtex, the elongation at break is 23%, the breaking strength is 4.02cN/dtex, the evenness of a network point is 98.5%, the breaking rate is 1.5%, the elongation at break variation coefficient is 5%, the on-line tension coefficient is 1.4%, the oiling rate is 2.92%, the dyeing M rate (qualification rate) is 99.3%, the appearance is free of broken filaments, stumbled filaments and tight spots, and after spinning, broken ends are few, the cloth cover is good and no cross bars are formed.

Example 8

wherein, the specification of the terylene POY is 16dtex/12f, the elongation at break is 113 percent, the breaking strength is 2.82cN/dtex, and the thermal stress is 14.5cN;

the technological parameters involved in the technological process are as follows: the pre-network air pressure is 0.05MPa, and the medium-network air pressure is 0.12MPa; the temperature of the first deformation hot box is 167 ℃; the temperature of the second shaping hot box is 130 ℃; the cooling temperature is 20 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first deformation hot box is 1.53; the false twister speed ratio was 1.62; the second wire feeding roller has a processing speed of 520 m/min; the overfeed rate of the yarn detector is-5.6%.

The total fineness of the prepared micro fine denier polyester filament yarn is 10.8dtex, the elongation at break is 22.8%, the breaking strength is 4.05cN/dtex, the evenness of network points is 98.5%, the yarn breaking rate is 1.1%, the elongation at break variation coefficient is 4.2%, the online tension coefficient is 1.36%, the oiling rate is 2.88%, the dyeing M rate (qualification rate) is 99.6%, the appearance is free of broken filaments, stumbled filaments and tight points, and after-spinning broken ends are few, the cloth cover is good and no cross bars are formed.

Claims

1. A preparation method of a micro-fine denier polyester filament yarn is characterized by comprising the following steps: using polyester POY as a raw material, and adopting a DTY process to prepare micro fine denier polyester filament yarns;

the middle network device adopts a network nozzle with a hole shape of a truncated cone, and the small end of the truncated cone faces to a wire running channel on the middle network device; the included angle between the movement direction of the silk in the silk running channel on the middle network device and the central axis of the circular truncated cone-shaped network nozzle is 90 degrees; when the silk strip just enters the silk-running channel, the moving direction of the silk strip and the air flow direction of the network nozzle form an angle of 70-80 degrees; when the yarn just exits the yarn running channel, the moving direction of the yarn and the air flow direction of the network nozzle form an angle of 100-110 degrees;

The oil tanker wire guide adopts a double-rotation oil tanker wire guide; the double-rotation oil tanker silk guide comprises a groove silk guide, a silk guide bracket, a main shaft and a main bearing; one end of the main shaft is fixedly connected with the inner ring of the main bearing;

the wire guide bracket is fixed on the outer ring of the main bearing through a large round hole; the other end of the main shaft sequentially passes through the anti-slip wire ring, the spacing ring, the oil frame, the gasket and the nut, and the main shaft is fixed on the oil frame by the nut; the bottom of the groove wire guide is provided with a bearing, and the bottom of the bearing is provided with a bearing seat; the bearing seat is arranged in the small round hole I through the small round hole II, and a shaft sequentially passes through one end of the small round hole I, the bearing seat and the other end of the small round hole I to fix the groove wire guide on the wire guide bracket;

the cooling device adopts a spiral hollow air cooling device and consists of an inner cylinder and an outer cylinder with different diameters, the area between the inner cylinder and the outer cylinder is sealed up and down, a hollow circular cold pipe is spirally wound in a sealed space, and an opening is respectively arranged on the upper part and the lower part of the sealed space and is respectively connected with the two ends of the hollow circular cold pipe.

2. The method for producing a fine denier polyester filament yarn as claimed in claim 1, wherein the diameter of the small opening of the truncated cone-shaped network nozzle is 0.8.+ -. 0.05mm, and the diameter of the large opening is 1.2.+ -. 0.05mm.

3. The method for producing a fine denier polyester filament yarn as claimed in claim 1, wherein the diameter of the inner cylinder is 5cm and the diameter of the outer cylinder is 8cm.

4. The method for preparing the micro fine denier polyester filament yarn according to claim 1, wherein the false twister adopts a combination mode of a ceramic disc, a polyurethane disc and a knife edge disc in a mode of 1-2-1, and the hardness of the polyurethane disc is 86A/D.

5. The method for producing a fine denier polyester filament yarn as claimed in claim 1, wherein the elongation at break of polyester POY is 115%, the breaking strength is 2.8cN/dtex, and the thermal stress is 16cN.

6. The method for producing a fine denier polyester filament yarn according to claim 1, wherein the pre-network air pressure is 0.03 to 0.05mpa, and the medium-network air pressure is 0.05 to 0.12mpa.

7. The method for preparing the micro-fine denier polyester filament yarn according to claim 1, wherein the temperature of the first deformation hot box is 160-170 ℃; the temperature of the second shaping hot box is 130-140 ℃; the cooling temperature is 20-25 ℃; the ratio of the speed of the second wire feeding roller to the speed of the first wire feeding roller is 1.5-1.6; the speed ratio of the false twister is 1.6-1.7; the processing speed of the second wire feeding roller is 500-600 m/min; the overfeeding rate of the shaping overfeeding roller is-6.0 to-5.5 percent.

8. The method for preparing the micro fine denier polyester filament yarn according to claim 1, wherein the oil application rate is 2.8-3.0%.

9. The method for preparing the micro fine denier polyester filament yarn according to any one of claims 1 to 8, wherein the total fineness of the micro fine denier polyester filament yarn is 5.5 to 10.8dtex, the elongation at break is 22.3 to 24%, the breaking strength is 4.0 to 4.15cN/dtex, the network point uniformity is not less than 98%, the yarn breakage rate is not more than 2%, the elongation at break variation coefficient is 4.0 to 5.0%, and the on-line tension coefficient is 1.3 to 1.4%.