A method for preparing a slubbed fiber

Abstract

The present application relates to a kind of preparation methods of bamboo fibre, the heat treatment is carried out to the partial length section of fibre in the drawing link in the continuous processing process of fibre, and the temperature of heat treatment is controlled to be higher than the glass transition temperature of fibre while lower than the melting point of fibre, and bamboo fibre is prepared;Or the heat treatment is carried out to the whole length section of fibre in the drawing link in the continuous processing process of fibre, and the heat treatment temperature of different length sections is not controlled to be completely same, and the temperature of heat treatment is controlled to be higher than the glass transition temperature of fibre while lower than the melting point of fibre, and bamboo fibre is prepared;The method of the present application is simple and convenient, and various different bamboo length, bamboo spacing filaments can be obtained by one-step method and production is stable, and the cloth sample woven can present the clear texture of concave-convex, and the dyeing style of raindrop, rain filament.

Description

Technical Field

[0001] This invention belongs to the field of textile and chemical fiber technology, and specifically relates to a method for preparing slub fiber. Background Technology

[0002] Slub yarn is a type of fiber that is either uniformly or unevenly distributed in the longitudinal direction. The same fiber will have a raised structure and will show different shades of color in the longitudinal direction when dyed. After being woven into fabric, it has a unique style and the finished product is fashionable, so it is highly favored.

[0003] Currently, most slub yarns on the market are prepared by compounding two or more finished yarns. For example, patent CN202110966713.3 uses a covered yarn method to prepare slub yarn, and patent CN207130409U uses three different colored yarns to prepare slub yarn. Alternatively, ring spinning structures are used to make the stretch ratio change regularly or irregularly during texturing to prepare DTY slub yarn. However, the above methods have many and complex production processes. Generally, at least conventional fibers must be obtained through spinning first, and then special processing technology is required to obtain slub yarn, resulting in a correspondingly high production cost.

[0004] In actual production, adjusting the yarn path or adding or removing production steps can lead to production instability, increased probability of waste yarn and broken yarn, and thus reduced yield.

[0005] Therefore, it is of great significance to study a simple and stable method for preparing bamboo fiber. Summary of the Invention

[0006] The purpose of this invention is to solve the problems existing in the prior art and to provide a method for preparing bamboo fiber.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A method for preparing bamboo fiber involves heat-treating a portion of the fiber length during the stretching stage of continuous fiber processing, and controlling the heat treatment temperature to be higher than the glass transition temperature of the fiber while lower than the melting point of the fiber, thereby obtaining bamboo fiber.

[0009] Alternatively, a method for preparing bamboo fiber involves heat-treating the entire length of the fiber during the stretching stage of continuous fiber processing, controlling the heat treatment temperature of different length segments to be not exactly the same, and controlling the heat treatment temperature to be higher than the glass transition temperature of the fiber while lower than the melting point of the fiber, thereby obtaining bamboo fiber.

[0010] As a preferred technical solution:

[0011] In the above-described method for preparing bamboo fiber, heat treatment is performed using a drawing roller, where the fiber moves along its own length direction while contacting the circumferential surface of the drawing roller, which rotates around its own central axis.

[0012] The circumferential surface of the drafting roller includes two independent regions, A and B, which are two regions that come into contact with the fiber successively when the drafting roller rotates around its own central axis.

[0013] When a portion of the fiber is heat-treated during the stretching stage in the continuous processing of the fiber, the temperature of region A is the temperature of the heat treatment, and the temperature of region B is lower than the glass transition temperature of the fiber. When a certain length of the fiber comes into contact with region A, the length is subjected to both heat treatment and stretching, ultimately forming a fine point. When a certain length of the fiber comes into contact with region B, the length is subjected to stretching only without heat treatment, ultimately forming a thick point.

[0014] When heat treatment is performed on the entire length of the fiber during the stretching stage in the continuous processing of the fiber, the temperatures of region A and region B are the heat treatment temperatures, with the temperature of region A being higher than that of region B. When a certain length of the fiber comes into contact with region A, that length is subjected to both strong heat treatment and stretching, ultimately forming a thin section. When a certain length of the fiber comes into contact with region B, that length is subjected to both weaker heat treatment and stretching, ultimately forming a thick section.

[0015] In the above-described method for preparing bamboo fiber, during the continuous processing of the fiber, the temperature of region B remains constant, the temperature of region A remains constant, or the temperature of region A changes regularly, or the temperature of region A changes irregularly.

[0016] In the above-described method for preparing slub fiber, the fiber does not move along the axial direction of the drafting roller when it comes into contact with the circumferential surface of the drafting roller. That is, it is assumed that the circumferential surface of the drafting roller is composed of multiple circles whose centers are all on the central axis of the drafting roller, and the fiber always contacts one of the circles on the circumferential surface of the drafting roller and does not contact the other circles. During the continuous processing of the fiber, the speed at which the fiber moves along its own length remains constant, and the speed at which the drafting roller rotates around its own central axis remains constant.

[0017] This involves at least two technical solutions: ① During the fiber drawing process, a portion of the fiber length is heat-treated, with the temperature of region A of the drawing roller being the heat treatment temperature, and the temperature of region B being lower than the glass transition temperature of the fiber; ② During the fiber drawing process, the entire length of the fiber (the length not in contact with region A and region B is ignored) is heat-treated, with the temperatures of region A and region B of the drawing roller being the heat treatment temperatures, and the temperature of region A being higher than the temperature of region B.

[0018] When the following three conditions are met simultaneously: "the fiber does not move along the axial direction of the drafting roller when it contacts the circumferential surface of the drafting roller," "during the continuous processing of the fiber, the speed at which the fiber moves along its own length remains constant, and the speed at which the drafting roller rotates around its own central axis remains constant," and "the temperature of region B remains constant," then when the temperature of region A remains constant, the detail length of the bamboo fiber remains constant, and the coarse section length remains constant; when the temperature of region A changes regularly, the detail length of the bamboo fiber changes regularly, and the coarse section length remains constant; when the temperature of region A changes irregularly, the detail length of the bamboo fiber changes irregularly, and the coarse section length remains constant.

[0019] Regarding technical solution ②, the temperature of region B can also be controlled to change irregularly or regularly in order to produce bamboo fiber with more diverse styles. Considering that the technical solution of keeping the temperature of region B constant is relatively simple, the present invention preferably keeps the temperature of region B constant, but this does not mean that the present invention must keep the temperature of region B constant.

[0020] Regarding technical solutions ① and ②, the fiber can also be controlled to move along the axial direction of the drafting roller when it contacts the circumferential surface, and the shapes of regions A and B can be adjusted so that the length of the heat-treated fiber segment changes continuously, thereby producing bamboo fibers with more diverse styles. Similarly, the speed at which the fiber moves along its own length direction can be controlled, and / or the speed at which the drafting roller rotates around its own central axis can be controlled, so that the length of the heat-treated fiber segment changes continuously, thereby producing bamboo fibers with more diverse styles.

[0021] In the above-described method for preparing bamboo fiber, the speed at which the fiber moves along its own length and the speed at which the drawing roller rotates around its own central axis are both in the range of 610 to 1100 m / min. Considering that the contact time between the fiber bundle and the drawing roller is relatively short, this invention controls the speed at which the fiber moves along its own length and the speed at which the drawing roller rotates around its own central axis to be relatively low. The purpose is to prolong the contact time between the fiber bundle and the drawing roller so that the fiber bundle can quickly reach the heat treatment temperature.

[0022] As described above, in the method for preparing bamboo fiber, regions A and B each contain four sides, one set of opposite sides being arc-shaped and the other set being straight sides; the surfaces containing the arc-shaped sides of regions A and B are parallel to or coplanar with the bottom surface of the drafting roller, and the straight sides of regions A and B are parallel to the central axis of the drafting roller; the shapes of regions A and B are not limited to this, but considering that this shape has a relatively simple structure and is easy to process, it is therefore the preferred technical solution of the present invention.

[0023] In the method for preparing slub fiber described above, the drawing roller includes a roller shaft and a cylinder sleeved on the roller shaft. Heaters and temperature sensors are installed at corresponding positions in regions A and B within the cylinder. The heaters and temperature sensors are electrically connected to a slip ring mounted on the roller shaft, and the slip ring is electrically connected to a control system located outside the drawing roller. The control system sends a signal to the heater via the slip ring to heat region A or region B. During this process, the temperature sensor monitors the temperature of region A or region B and feeds it back to the control system via the slip ring. The control system adjusts the signal sent to the heater based on the feedback information, and this cycle repeats until the temperature of region A or region B reaches a set value. Furthermore, it should be noted that when the temperature of region B is lower than the glass transition temperature of the fiber, the heater and temperature sensor do not need to be installed inside the cylinder of region B; even if the heater and temperature sensor are installed, they can be controlled to not operate.

[0024] In the above-described method for preparing bamboo fiber, the diameter of the drawing roller is 15-35 cm, the length of the arc-shaped side in region A is 18.8-66 cm, and the length of the arc-shaped side in region B is 9.4-44 cm.

[0025] In the above-described method for preparing bamboo fiber, the length of the portion of the circumferential area of ​​the drawing roller that contacts the fiber is L, where L is 0.2 to 0.8 times the circumference of the drawing roller.

[0026] The preparation method of bamboo fiber as described above is as follows: the slices are sequentially passed through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide roller, drawing roller, second guide roller, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0027] Specific process parameters can be adjusted according to the material of the bamboo fiber and actual needs. Taking nylon 6 bamboo fiber as an example, the rotation speed of the first roller is 600-1000 m / min, and the temperature is 60-90℃; the rotation speed of the drawing roller is 610-1100 m / min, and the temperature of zone A is 180-205℃; the rotation speed of the second roller is 1040-1560 m / min, and the temperature is room temperature; the rotation speed of the third roller is 2710-4100 m / min, and the temperature is 130-190℃; the speed of the guide disc is 2680-4070 m / min; and the winding speed is 2600-4000 m / min.

[0028] The speed of one roller is lower than that of conventional products for the following reasons: ① To reduce fiber nozzle stretching, allowing for more elongation during subsequent stretching processes, thus enhancing the slub yarn effect; ② To reduce spinning speed and improve spinning stability. The temperature of the first roller is set to ensure the yarn bundle reaches above the Tg temperature, allowing it to reach the processing temperature more quickly during subsequent stretching. During processing, the length of the contact area between the yarn bundle and the drafting roller (i.e., L mentioned above) is controlled by adjusting the position of the first and second guides. The longer the contact length between the yarn bundle and the heating area of ​​the drafting roller, the shorter the slub yarn length and the longer the slub spacing; conversely, the shorter the contact length between the yarn bundle and the heating area of ​​the drafting roller, the shorter the slub yarn length and the longer the slub spacing. The longer the stretch, the shorter the spacing between the slub segments. The speed of the drafting roller is slightly higher than that of the first roller, but it is still lower than that of the conventional roller, and the temperature setting is higher. This is because the filaments spend less time on the drafting roller. Therefore, by reducing the speed and increasing the temperature, the filaments can quickly reach the processing temperature. The stretch ratio between the second roller and the first roller is one of the key steps in the production of slub yarn. Due to the stretch ratio, when the speed of each roller remains constant, the filaments pass through different areas of the drafting roller. That is, the filaments are stretched more and the fibers are finer when passing through the heated zone, and less and the fibers are coarser when passing through the unheated zone. The stretch ratio affects the difference in thickness between the coarse and fine segments of the slub yarn. The larger the stretch ratio, the greater the difference in thickness, and vice versa.

[0029] The method for preparing bamboo fiber described above involves heat-treating a portion of the fiber length and controlling the heat treatment temperature to be higher than the fiber's glass transition temperature while lower than its melting point. This is achieved by controlling the fiber to move along its own length direction while alternately contacting the circumferential surfaces of length segment A and length segment B of the drawing roller. The temperature of length segment A is controlled to be higher than the fiber's glass transition temperature while lower than its melting point, and the temperature of length segment B is controlled to be lower than the fiber's glass transition temperature.

[0030] The method for preparing bamboo fiber described above involves heat-treating the entire length of the fiber, controlling the heat treatment temperatures of different length segments to be not entirely the same, and controlling the heat treatment temperature to be higher than the glass transition temperature of the fiber while lower than the melting point of the fiber. This is achieved by controlling the fiber to move along its own length direction while alternately contacting the circumferential surfaces of length segment A and length segment B of the drawing roller, and controlling the temperature of length segment A to be higher than the glass transition temperature of the fiber while lower than the melting point of the fiber, and the temperature of length segment B to be higher than the glass transition temperature of the fiber while lower than the melting point of the fiber and lower than the temperature of length segment A.

[0031] In the method for preparing slub fiber as described above, the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller by controlling the drawing roller to remain stationary along the axial direction while controlling the fiber to reciprocate along the axial direction of the drawing roller.

[0032] In the method for preparing slub fiber described above, both length segments A and B of the drawing roller include roller shafts and rollers fitted onto the roller shafts. Heaters and temperature sensors are installed inside the rollers of both length segments A and B. The heaters and temperature sensors are electrically connected to slip rings mounted on the corresponding roller shafts of the rollers. The slip rings are electrically connected to a control system located outside the drawing roller. The control system sends a signal to the heaters via the slip rings to heat length segment A or length segment B. During this process, the temperature sensors monitor the temperature of length segment A or length segment B and feed it back to the control system via the slip rings. The control system adjusts the signal sent to the heaters based on the feedback information. This cycle repeats until the temperature of length segment A or length segment B reaches a set value. Furthermore, it should be noted that when the temperature of length segment B is lower than the glass transition temperature of the fiber, the heaters and temperature sensors do not need to be installed inside the rollers of length segment B. Even if the heaters and temperature sensors are installed, they can be controlled to not operate.

[0033] In the method for preparing bamboo fiber as described above, a length segment C is provided between length segment A and length segment B of the drawing roller. Length segment C is made of heat-insulating material. Length segments A, B, and C are coaxial. Length segments A and B are cylindrical structures with lengths ranging from 10 to 20 cm. The diameter of length segment A is 0.1 to 0.5 cm larger than that of length segment B, and the diameter of length segment B ranges from 7 to 15 cm. Length segment C is a frustum-shaped structure with the same diameter at the large end as length segment A and the same diameter at the small end as length segment B, and its length ranges from 2 to 4 cm. In this invention, the diameter of length segment A is greater than... The length segment B allows the filament bundle to travel a greater distance on the roller when passing through length segment A. Since the speeds of the two rollers before and after the temperature-controlled roller remain constant, the tensile force on the filament bundle is constant between them. When the filament bundle passes through length segment A, it is heated. The larger the diameter of length segment A, the greater the distance the filament bundle travels on its circumference, the more the filament bundle is stretched, and the finer the filament is obtained. When the filament bundle passes through length segment B, it is not heated or is heated at a lower temperature. The smaller the diameter of length segment B, the smaller the distance the filament bundle travels on its circumference, the less the filament bundle is stretched, and the thicker the filament is obtained.

[0034] In the above-described method for preparing bamboo fiber, during the continuous processing of the fiber, the temperature of length segment B remains constant, the temperature of length segment A remains constant, or the temperature of length segment A changes regularly, or the temperature of length segment A changes irregularly.

[0035] In the above-described method for preparing slub fiber, during the continuous processing of the fiber, the drawing roller rotates around its own central axis; during the continuous processing of the fiber, the speed at which the fiber moves along its own length remains constant, the speed at which the drawing roller rotates around its own central axis remains constant, and the frequency of the fiber's axial reciprocating motion along the drawing roller remains constant.

[0036] This involves at least two technical solutions: ① During the fiber drawing process, a portion of the fiber length is heat-treated, with the temperature of length segment A of the drawing roller being the heat treatment temperature, and the temperature of length segment B being lower than the glass transition temperature of the fiber; ② During the fiber drawing process, the entire length of the fiber (length segments not in contact with length segments A and B are ignored) is heat-treated, with the temperatures of length segments A and B of the drawing roller being the heat treatment temperatures, and the temperature of length segment A being higher than the temperature of length segment B;

[0037] When both conditions are met simultaneously, namely, "during continuous fiber processing, the fiber's speed along its own length remains constant, the speed of the drawing roller's rotation around its own central axis remains constant, and the frequency of the fiber's axial reciprocating motion along the drawing roller remains constant" and "the temperature of length segment B remains constant," then when the temperature of length segment A remains constant, the detail length of the bamboo fiber remains constant, and the coarse section length remains constant; when the temperature of length segment A changes regularly, the detail length of the bamboo fiber changes regularly, and the coarse section length remains constant; when the temperature of length segment A changes irregularly, the detail length of the bamboo fiber changes irregularly, and the coarse section length remains constant.

[0038] Regarding technical solution ②, the temperature of length segment B can also be controlled to change irregularly or regularly in order to produce bamboo fiber with more diverse styles. Considering that the technical solution of keeping the temperature of length segment B constant is relatively simple, the present invention preferably keeps the temperature of length segment B constant, but this does not mean that the present invention must keep the temperature of length segment B constant.

[0039] Regarding technical solutions ① and ②, the speed at which the fiber moves along its own length, the speed at which the drafting roller rotates around its own central axis, or the frequency of the fiber's axial reciprocating motion along the drafting roller can also be controlled to continuously change the length of the heat-treated section of the fiber, thereby producing bamboo fiber with more diverse styles.

[0040] In the above-described method for preparing bamboo fiber, the speed at which the fiber moves along its own length and the speed at which the drafting roller rotates around its own central axis are both in the range of 610–1100 m / min. Considering that the contact time between the fiber bundle and the drafting roller is relatively short, this invention controls the speed at which the fiber moves along its own length and the speed at which the drafting roller rotates around its own central axis to be relatively low. The purpose is to prolong the contact time between the fiber bundle and the drafting roller so that the fiber bundle can quickly reach the heat treatment temperature. The frequency of the fiber reciprocating along the axial direction of the drafting roller is in the range of 2100–3000 R / min (rounds / second, where one round is the guide wire moving back and forth along the guide rod once).

[0041] As described above, in a method for preparing slub fiber, two guiding mechanisms are used to control the reciprocating motion of the fiber along the axial direction of the drawing roller, namely a first guiding mechanism and a second guiding mechanism.

[0042] The first guide wire mechanism includes a crossbar, a transverse track, a guide wire, and a transverse drive device. The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The guide wire is fixedly connected to the crossbar.

[0043] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism;

[0044] Two fiber guiding mechanisms are arranged at intervals along the direction of fiber movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

[0045] The preparation method of bamboo fiber as described above is as follows: the slices are sequentially passed through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, drawing roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0046] Specific process parameters can be adjusted according to the material of the bamboo fiber and actual needs. Taking nylon 6 bamboo fiber as an example, the rotation speed of the first roller is 600-1000 m / min and the temperature is 60-90℃; the rotation speed of the drawing roller is 610-1100 m / min and the temperature of length section A is 180-205℃; the rotation speed of the second roller is 1040-1560 m / min and the temperature is room temperature; the rotation speed of the third roller is 2710-4100 m / min and the temperature is 130-190℃; the speed of the guide disc is 2680-4070 m / min; and the winding speed is 2600-4000 m / min.

[0047] The speed of one roller is lower than that of conventional products for the following reasons: ① To reduce fiber nozzle stretching, allowing for more elongation during subsequent stretching processes, resulting in a more pronounced slub yarn effect; ② To reduce spinning speed and improve spinning stability. The temperature of the first roller is set to ensure the yarn bundle reaches above Tg, allowing it to reach the processing temperature more quickly during subsequent stretching. During processing, the length of the contact area between the yarn bundle and the drafting roller (i.e., L mentioned above) is controlled by adjusting the position of the first and second guides. A longer contact area results in a longer slub yarn, and vice versa. The drafting roller rotates at a slightly higher speed than the first roller, but... The speed is still relatively low compared to conventional rollers, and the temperature setting is relatively high, both because the filaments spend less time on the drafting rollers. Therefore, by reducing the speed and increasing the temperature, the filaments can quickly reach the processing temperature. The certain stretch ratio between the two rollers and the first roller is one of the key steps in the production of slub yarn. Due to the existence of the stretch ratio, when the speed of each roller remains constant, the filaments pass through different areas of the drafting rollers. That is, the filaments are stretched more and the fibers are finer when passing through the heated zone, and the filaments are stretched less and the fibers are coarser when passing through the unheated zone. The stretch ratio affects the difference in thickness between the coarse and fine segments of the slub yarn. The larger the stretch ratio, the greater the difference in thickness, and vice versa.

[0048] In the method for preparing bamboo fiber as described above, the wind speed changes regularly or irregularly during side blowing, and / or the wind temperature changes regularly or irregularly.

[0049] The method for preparing bamboo fiber as described above uses a side-blowing fan cabinet, which includes an air inlet pipe, a damper, a filter, a side-blowing fan, a cabinet body, and a rotary air control mechanism.

[0050] The rotary wind control mechanism consists of a motor, a rotating column, and blades. The motor is connected to the rotating column and is used to drive the rotating column to rotate around its own central axis at a uniform or variable speed. The rotating column has n strip slots parallel to the central axis of the rotating column, where n is a positive integer greater than 2. The number of blades is the same as the number of strip slots, and each blade is installed in a different strip slot.

[0051] At least two blades have holes, and the number of holes is different; and / or at least two blades have embedded heating wires, which are electrically connected to a fixed power supply through a collector ring set on a rotating column.

[0052] The rotary air control mechanism is located inside the cabinet and above the filter screen, dividing the space above the filter screen inside the cabinet into upper and lower parts, which are connected by holes on the blades. The invention adjusts the air speed by controlling the side airflow to blow through blades with different numbers of holes, and adjusts the air temperature by controlling the side airflow to blow through blades with different temperatures.

[0053] In the production process of conventional fibers, it is necessary to ensure the uniformity and stability of side blowing and stretching to ensure the uniformity of fiber thickness. This invention changes the original uniform and stable side blowing by using a rotary air control mechanism to make it a side blowing mechanism with variable wind speed and temperature, which helps to obtain pre-spun fibers such as slub or POY with uneven longitudinal thickness distribution.

[0054] As described above, in the method for preparing slub fiber, the fiber forms a V-shape after contacting the drafting roller. The reason this invention does not involve winding the fiber bundle several times on the drafting roller as in conventional spinning is to ensure stability during the spinning process. The length of the portion of the drafting roller's circumferential area in contact with the fiber is L. When the fiber denier is less than 50D, L is 0.2 to 0.5 times the circumference of length segments A and B of the drafting roller. When the fiber denier is greater than or equal to 50D, L is 0.5 to 0.8 times the circumference of length segments A and B of the drafting roller. At the same temperature and speed, because low-denier fibers are finer, their macromolecular chains can obtain the energy required for movement more quickly under the heating of the drafting roller, so L can be smaller. High-denier fibers require a longer time for their macromolecular chains to obtain the energy required for movement, so L needs to be larger. Similarly, low-denier fibers cool quickly, while high-denier fibers cool slowly.

[0055] The principle of this invention is as follows:

[0056] This invention achieves slub yarn with uneven longitudinal thickness distribution by adjusting the production process and changing the drafting temperature. In existing technologies, although waste yarn also exhibits uneven thickness, it cannot be directly used as slub yarn. This is because only a small section of a long waste yarn fiber has uneven thickness, and such yarn cannot be called slub yarn. It will not display varying shades after dyeing, and the woven fabric will lack a unique style. Furthermore, during the spinning process, the smaller the yarn bundle vibration, the more stable the yarn path, and the more stable the production. Conversely, the greater the yarn bundle vibration, the less stable the yarn path, and the worse the production stability. Yarn breakage is more likely during production, severely impacting production efficiency and product quality. Therefore, maintaining the stability of the yarn bundle throughout the yarn path is of paramount importance. While this invention reduces and optimizes the preparation process of slub yarn, producing slub fiber in a single step, it still effectively controls the stability of the yarn bundle, maintaining production stability and possessing practical production significance.

[0057] Beneficial effects:

[0058] The present invention discloses a method for preparing bamboo fiber, which is simple and convenient to produce. It can obtain filaments with different bamboo lengths and bamboo spacing in one step, and the production is stable. The fabric woven from it can present a texture with distinct concave and convex features, as well as a dyeing style with raindrops and rain threads. This style of fabric is very popular in the market. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the side-blowing fan cabinet of the present invention;

[0060] Figure 2 This is a partial schematic diagram of the side-blowing fan cabinet of the present invention;

[0061] Figure 3 This is a schematic diagram of the perforated blade of the present invention;

[0062] Figure 4 This is a top view of the two wire guiding mechanisms and the drawing roller of the present invention;

[0063] Figure 5 The guide wire mechanism of this invention;

[0064] Figure 6 The drawing roller of this invention;

[0065] Figures 7-8 These are graphs showing the relationship between temperature and time.

[0066] Figure 9 Images of bamboo fibers from Example 5, taken using a microscope;

[0067] Figures 10-11 These are curves showing the changes in temperature and time, respectively.

[0068] Figure 12 Images of bamboo fibers obtained in Example 12, taken using a microscope;

[0069] Among them, 1-filter screen, 2-side blowing screen, 3-cabinet, 4-rotary air control mechanism, 41-motor, 42-rotating column, 43-blade, 5-collector ring, 6-fiber guide mechanism, 7-crossbar, 8-transverse track, 9-fiber guide, 10-cylinder, 11-drawing roller, 12-fiber. Detailed Implementation

[0070] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0071] In the following examples, the breaking strength and breaking elongation of the fibers were tested according to the national standard GB / T 14344. Twelve samples were tested, and each sample was tested three times. The breaking strength and breaking elongation of each sample were the average of the three tests. The breaking strength and breaking elongation of the slub yarn samples in Examples 1 and 2 were the average of the twelve samples. The breaking strength and breaking elongation of the slub yarn samples in Examples 3 to 6 were between the maximum and minimum values ​​among the twelve samples.

[0072] The fiber fineness test method in the following examples was carried out in accordance with the national standard GB / T 14343. The fineness of the slub yarn samples in Examples 1 and 2 was the average value of 12 samples; the fineness of the slub yarn samples in Examples 3 to 6 was between the maximum and minimum values ​​of 12 samples.

[0073] Example 1

[0074] A type of side-blowing cabinet, such as Figures 1-3 As shown, the side-blowing cabinet includes an air inlet pipe, an air valve, a filter screen 1, a side-blowing air screen 2, a cabinet 3, and a rotary air control mechanism 4. This side-blowing cabinet is equivalent to adding a rotary air control mechanism 4 to a side-blowing cabinet with a length of 170cm, a width of 20cm, and a height of 200cm in the existing technology.

[0075] The rotary wind control mechanism 4 consists of a motor 41, a rotating column 42 (with a hollow structure, an outer diameter of 3cm, and a length of 170cm), and blades 43. The motor 41 is connected to the rotating column 42 and is used to drive the rotating column 42 to rotate at a constant speed around its own central axis. Figure 1 As shown, the rotation direction is clockwise when viewed from the right side, and the rotation speed is 8s / r (i.e., seconds / revolution, the same below); there are 6 strip-shaped slots parallel to the central axis of the rotating column 42 on the circumference of the rotating column 42; the number of blades 43 is the same as the number of strip-shaped slots, and each blade 43 is installed in a different strip-shaped slot. The part of the blade 43 that protrudes from the strip-shaped slot is rectangular in shape, with a length of 168cm and a width of 8cm, and the long side is parallel to the central axis of the rotating column 42;

[0076] There are 6 leaves and 43 types, namely leaf A, leaf B and leaf C, with 2 leaves of each type.

[0077] Blade A: 30 holes with a diameter of 2cm are evenly distributed on the surface, and heating wires are embedded inside. The heating wires are electrically connected to a fixed power supply through the collector ring 5 set on the rotating column 42. When the side blowing cabinet is working, the heating wires heat blade A to 28℃.

[0078] Blade B: No holes on the surface, no heating wire inside;

[0079] Blade C: 15 holes with a diameter of 2cm are evenly distributed on the surface, without heating wire inside;

[0080] Two blades A are installed diagonally, two blades B are installed diagonally, and two blades C are installed diagonally, with each blade B located between blades A and C;

[0081] The rotary air control mechanism 4 is located inside the cabinet 3 and above the filter screen 1, dividing the space above the filter screen 1 inside the cabinet 3 into upper and lower parts. The upper and lower parts are connected by holes on the blades 43. The distance between the rotating column 42 and the filter screen 1 is 20cm, the distance between the filter screen 1 and the bottom of the side blowing cabinet is 40cm, and the length of the side blowing net 2 in the vertical direction is 145cm.

[0082] Example 2

[0083] A side-blowing cabinet includes an air inlet pipe, an air valve, a filter screen, a side-blowing screen, a cabinet body, and a rotary air control mechanism. This side-blowing cabinet is equivalent to adding a rotary air control mechanism to a conventional side-blowing cabinet with a length of 116cm, a width of 20cm, and a height of 200cm.

[0084] The rotary wind control mechanism consists of a motor, a rotating column (with a hollow structure, an outer diameter of 3cm, and a length of 116cm), and blades. The motor is connected to the rotating column and drives it to rotate at a constant speed around its central axis. Figure 1 As shown, the rotation direction is clockwise when viewed from the right side, and the rotation speed is 8s / r; there are 6 strip-shaped slots parallel to the central axis of the rotating column on the circumference of the rotating column; the number of blades is the same as the number of strip-shaped slots, and each blade is installed in a different strip-shaped slot. The part of the blade that protrudes from the strip-shaped slot is rectangular in shape, with a length of 114cm and a width of 8cm, and the long side is parallel to the central axis of the rotating column.

[0085] In a clockwise direction, the six blades are respectively designated as the first blade, the second blade, the third blade, the fourth blade, the fifth blade, and the sixth blade;

[0086] First blade: 30 holes with a diameter of 1.5cm are evenly distributed on the surface, and heating wires are embedded in them. The heating wires are electrically connected to a fixed power supply through a collector ring set on the rotating column. When the side blowing cabinet is working, the heating wires heat the first blade to 28℃.

[0087] Second blade: No holes on the surface, no heating wire inside;

[0088] The third blade has 15 holes with a diameter of 1.5cm evenly distributed on its surface, each containing a heating wire. The heating wire is electrically connected to a fixed power supply through a collector ring set on the rotating column. When the side blower is working, the heating wire heats the first blade to 28°C.

[0089] Fourth blade: 30 holes with a diameter of 1.5cm are evenly distributed on the surface, without heating wire inside;

[0090] Fifth blade: No holes on the surface, no heating wire inside;

[0091] The sixth blade has 15 holes with a diameter of 1.5cm evenly distributed on its surface, each containing a heating wire. The heating wire is electrically connected to a fixed power supply through a collector ring set on the rotating column. When the side blower is working, the heating wire heats the first blade to 28°C.

[0092] The first blade and the fourth blade are installed diagonally, the second blade and the fifth blade are installed diagonally, and the third blade and the sixth blade are installed diagonally.

[0093] The rotary air control mechanism is located inside the cabinet and above the filter screen, dividing the space above the filter screen inside the cabinet into upper and lower parts. The upper and lower parts are connected by holes on the blades. The distance between the rotating column and the filter screen is 20cm, the distance between the filter screen and the bottom of the side blowing cabinet is 40cm, and the length of the side blowing screen in the vertical direction is 145cm.

[0094] Example 3

[0095] A side-blowing cabinet includes an air inlet pipe, an air valve, a filter screen, a side-blowing screen, a cabinet body, and a rotary air control mechanism. This side-blowing cabinet is equivalent to adding a rotary air control mechanism to a conventional side-blowing cabinet with a length of 116cm, a width of 20cm, and a height of 200cm.

[0096] The rotary wind control mechanism consists of a motor, a rotating column (with a hollow structure, an outer diameter of 3cm, and a length of 116cm), and blades. The motor is connected to the rotating column and drives it to rotate at a constant speed around its central axis. Figure 1 As shown, the rotation direction is clockwise when viewed from the right side, and the rotation speed is 8s / r; there are 6 strip-shaped slots parallel to the central axis of the rotating column on the circumference of the rotating column; the number of blades is the same as the number of strip-shaped slots, and each blade is installed in a different strip-shaped slot. The part of the blade that protrudes from the strip-shaped slot is rectangular in shape, with a length of 114cm and a width of 8cm, and the long side is parallel to the central axis of the rotating column.

[0097] The six leaves are divided into three types: leaf A, leaf B, and leaf C, with two leaves of each type.

[0098] Blade A: The surface has 30 holes with a diameter of 1 cm evenly distributed, and there are no heating wires inside;

[0099] Blade B: 30 holes with a diameter of 1cm are evenly distributed on the surface (same as the holes of blade A). An electric heating wire is embedded in the hole. The electric heating wire is electrically connected to a fixed power supply through a collector ring set on the rotating column. When the side blowing cabinet is working, the electric heating wire heats blade B to 28℃.

[0100] Blade C: 30 holes with a diameter of 1 cm are evenly distributed on the surface (same as the holes in blade A), and there is no heating wire inside;

[0101] Two blades A are installed diagonally, two blades B are installed diagonally, and two blades C are installed diagonally, with each blade B located between blades A and C;

[0102] The rotary air control mechanism is located inside the cabinet and above the filter screen, dividing the space above the filter screen inside the cabinet into upper and lower parts. The upper and lower parts are connected by holes on the blades. The distance between the rotating column and the filter screen is 20cm, the distance between the filter screen and the bottom of the side blowing cabinet is 40cm, and the length of the side blowing screen in the vertical direction is 145cm.

[0103] Example 4

[0104] A side-blowing cabinet includes an air inlet pipe, an air valve, a filter screen, a side-blowing screen, a cabinet body, and a rotary air control mechanism. This side-blowing cabinet is equivalent to adding a rotary air control mechanism to a conventional side-blowing cabinet with a length of 92cm, a width of 20cm, and a height of 200cm.

[0105] The rotary wind control mechanism consists of a motor, a rotating column (with a hollow structure, an outer diameter of 3cm, and a length of 92cm), and blades. The motor is connected to the rotating column and drives it to rotate at a constant speed around its central axis. Figure 1 As shown, the rotation direction is clockwise when viewed from the right side, and the rotation speed is 8s / r; there are 6 strip-shaped slots parallel to the central axis of the rotating column on the circumference of the rotating column; the number of blades is the same as the number of strip-shaped slots, and each blade is installed in a different strip-shaped slot. The part of the blade that protrudes from the strip-shaped slot is rectangular in shape, with a length of 90cm and a width of 8cm, and the long side is parallel to the central axis of the rotating column;

[0106] The six blades are divided into six types: blade A, blade B, blade C, blade D, blade E, and blade F.

[0107] Blade A: 20 holes with a diameter of 1cm are evenly distributed on the surface, and there is no heating wire inside;

[0108] Blade B: 15 holes with a diameter of 0.9 cm are evenly distributed on the surface, and there is no heating wire inside;

[0109] Blade C: The surface is free of holes and there is no heating wire inside;

[0110] Blade D: The surface has 30 holes with a diameter of 1 cm evenly distributed, and there are no heating wires inside;

[0111] Blade E: 25 holes with a diameter of 0.8 cm are evenly distributed on the surface, and there is no heating wire inside;

[0112] Blade F: The surface has 10 holes with a diameter of 1.5cm evenly distributed, and there is no heating wire inside;

[0113] The blade installation sequence is: blade A, blade B, blade C, blade D, blade E, blade F;

[0114] The rotary air control mechanism is located inside the cabinet and above the filter screen, dividing the space above the filter screen inside the cabinet into upper and lower parts. The upper and lower parts are connected by holes on the blades. The distance between the rotating column and the filter screen is 20cm, the distance between the filter screen and the bottom of the side blowing cabinet is 40cm, and the length of the side blowing screen in the vertical direction is 145cm.

[0115] Example 5

[0116] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0117] (1) Preparation of slices;

[0118] Chips: Semi-dull PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0119] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, stretching roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0120] Among them, the side-blowing air adopts the side-blowing air cabinet of Example 1, and the temperature of the side-blowing air flowing through the filter screen is 18.5℃ and the wind speed is 0.75m / s;

[0121] The drafting roll consists of length segments A, B, and C. Length segment C, made of heat-insulating material, is located between length segments A and B, isolating them (to prevent heat exchange). Length segments A, B, and C are coaxial. Length segments A and B are cylindrical, with lengths of 10cm and 10cm respectively. The diameter of length segment A is 0.5cm larger than that of length segment B, which has a diameter of 15cm. Length segment C is frustum-shaped, with the larger end having the same diameter as length segment A and the smaller end having the same diameter as length segment B. Length segment C has a length of 2.5cm. Each of the drafting roll's length segments A, B, and C includes a roller shaft and a cylinder fitted onto the shaft. Heaters and temperature sensors are installed inside the cylinders of length segments A and B. These heaters and temperature sensors are electrically connected to slip rings on the corresponding roller shafts, and the slip rings are electrically connected to a control system located outside the drafting roll.

[0122] In the drawing stage of the continuous fiber processing, the drawing roller is kept stationary along the axial direction while the fiber moves along its own length. At the same time, the first guide mechanism and the second guide mechanism are used to control the fiber to reciprocate along the axial direction of the drawing roller, so that the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller.

[0123] After the fiber comes into contact with the drafting roller, it forms a V-shape. The length of the part of the drafting roller's circumferential area in contact with the fiber is L. When it is on the length segment A of the drafting roller, L is 0.8 times the circumference of the length segment A of the drafting roller.

[0124] like Figures 4-6 As shown, the first guide wire mechanism includes a crossbar 7, a transverse track 8, a guide wire 9, and a transverse drive device (i.e., a cylinder 10). The crossbar 7 and the transverse track 8 are both parallel to the central axis of the drafting roller 11. The crossbar 7 is slidably connected to the transverse track 8. The transverse drive device is used to drive the crossbar 7 to reciprocate on the transverse track 8. The guide wire 9 is fixedly connected to the crossbar 7.

[0125] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism (the first and second guidewire mechanisms are guidewire mechanism 6 in the figure);

[0126] Two fiber guiding mechanisms are arranged at intervals along the direction of fiber 12 and distributed on both sides of the drafting roller 11; the fiber passes through the guide 9 of both fiber guiding mechanisms simultaneously;

[0127] The process parameters for preparing bamboo fiber are as follows: the first roller speed is 600 m / min and the temperature is 85℃; the second roller speed is 1150 m / min and the temperature is 25℃; the third roller speed is 3100 m / min and the temperature is 175℃; the guide disc speed is 3050 m / min; the winding speed is 3000 m / min; the fiber moves along its own length at a speed of 610 m / min; the drafting roller rotates around its own central axis at a speed of 610 m / min; the frequency of the fiber's axial reciprocating motion along the drafting roller is 2100 R / min (rounds / second, the same below); the temperature of length section B is 25℃, and the temperature of length section A is 205℃.

[0128] No head breakage occurred during continuous processing for 108 hours in the preparation process.

[0129] The obtained bamboo fiber is like Figure 9 As shown, the fineness of bamboo fiber is 70.4D, the breaking strength is 4.31cN / dtex, and the breaking elongation is 46.2%.

[0130] Example 6

[0131] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0132] (1) Preparation of slices;

[0133] Chips: Fully matte PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0134] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, stretching roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0135] Among them, the side-blowing air adopts the side-blowing air cabinet of Example 1, and the temperature of the side-blowing air flowing through the filter screen is 18.4℃ and the wind speed is 0.77m / s;

[0136] The drafting roll consists of length segments A, B, and C. Length segment C, made of heat-insulating material, is located between length segments A and B, isolating them (to prevent heat exchange). Length segments A, B, and C are coaxial. Length segments A and B are cylindrical, with lengths of 10cm and 10cm respectively. The diameter of length segment A is 0.5cm larger than that of length segment B, which has a diameter of 15cm. Length segment C is frustum-shaped, with the larger end having the same diameter as length segment A and the smaller end having the same diameter as length segment B. Length segment C has a length of 2.5cm. Each of the drafting roll's length segments A, B, and C includes a roller shaft and a cylinder fitted onto the shaft. Heaters and temperature sensors are installed inside the cylinders of length segments A and B. These heaters and temperature sensors are electrically connected to slip rings on the corresponding roller shafts, and the slip rings are electrically connected to a control system located outside the drafting roll.

[0137] In the drawing stage of the continuous fiber processing, the drawing roller is kept stationary along the axial direction while the fiber moves along its own length. At the same time, the first guide mechanism and the second guide mechanism are used to control the fiber to reciprocate along the axial direction of the drawing roller, so that the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller.

[0138] After the fiber comes into contact with the drafting roller, it forms a V-shape. The length of the part of the drafting roller's circumferential area in contact with the fiber is L. When it is on the length segment A of the drafting roller, L is 0.8 times the circumference of the length segment A of the drafting roller.

[0139] The first wire guiding mechanism includes a crossbar, a transverse track, a wire guide, and a transverse drive device (i.e., a cylinder). The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The wire guide is fixedly connected to the crossbar.

[0140] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism;

[0141] Two fiber guiding mechanisms are arranged at intervals along the fiber's direction of movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

[0142] The process parameters for preparing bamboo fiber are as follows: the first roller speed is 600 m / min and the temperature is 85℃; the second roller speed is 1150 m / min and the temperature is 26℃; the third roller speed is 3100 m / min and the temperature is 175℃; the guide disc speed is 3050 m / min; the winding speed is 3000 m / min; the fiber moves along its own length at a speed of 610 m / min; the drafting roller rotates around its own central axis at a speed of 610 m / min; the frequency of the fiber's axial reciprocating motion along the drafting roller is 2100 R / min; the temperature of length section B is 26℃; and the temperature of length section A is 205℃.

[0143] No head breakage occurred during continuous processing for 106 hours in the preparation process.

[0144] The obtained bamboo fiber has a fineness of 70.6D, a breaking strength of 4.35cN / dtex, and a breaking elongation of 47%.

[0145] Example 7

[0146] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0147] (1) Preparation of slices;

[0148] Chips: High-gloss PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0149] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, stretching roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0150] Among them, the side-blowing air adopts the side-blowing air cabinet of Example 2, and the temperature of the side-blowing air flowing through the filter screen is 19.5℃ and the wind speed is 0.68m / s;

[0151] The drafting roll consists of length segments A, B, and C. Length segment C, made of heat-insulating material, is located between length segments A and B, isolating them (to prevent heat exchange). Length segments A, B, and C are coaxial. Length segments A and B are cylindrical, with lengths of 10cm and 10cm respectively. The diameter of length segment A is 0.4cm larger than that of length segment B, which has a diameter of 14cm. Length segment C is frustum-shaped, with the larger end having the same diameter as length segment A and the smaller end having the same diameter as length segment B. Length segment C has a length of 2.5cm. Length segments A, B, and C all contain roller shafts and cylinders fitted onto these shafts. Heaters and temperature sensors are installed inside the cylinders of length segments A and B. These heaters and temperature sensors are electrically connected to slip rings on the corresponding roller shafts, and the slip rings are electrically connected to a control system located outside the drafting roll.

[0152] In the drawing stage of the continuous fiber processing, the drawing roller is kept stationary along the axial direction while the fiber moves along its own length. At the same time, the first guide mechanism and the second guide mechanism are used to control the fiber to reciprocate along the axial direction of the drawing roller, so that the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller.

[0153] After the fiber comes into contact with the drafting roller, it forms a V-shape. The length of the part of the drafting roller's circumferential area in contact with the fiber is L. When it is on the length segment A of the drafting roller, L is 0.6 times the circumference of the length segment A of the drafting roller.

[0154] The first wire guiding mechanism includes a crossbar, a transverse track, a wire guide, and a transverse drive device (i.e., a cylinder). The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The wire guide is fixedly connected to the crossbar.

[0155] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism;

[0156] Two fiber guiding mechanisms are arranged at intervals along the fiber's direction of movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

[0157] The process parameters for preparing bamboo-joint fibers are as follows: the first roller speed is 700 m / min and the temperature is 75℃; the second roller speed is 1350 m / min and the temperature is 25℃; the third roller speed is 3600 m / min and the temperature is 160℃; the guide disc speed is 3560 m / min; the winding speed is 3500 m / min; the fiber moves at a speed of 710 m / min along its own length direction; the drafting roller rotates at a speed of 710 m / min around its own central axis; the frequency of the fiber reciprocating along the axial direction of the drafting roller is 2520 R / min; the temperature of length section B is 90℃, and the temperature of length section A is 195℃.

[0158] No head breakage occurred during continuous processing for 95 hours in the preparation process.

[0159] The obtained bamboo fiber has a fineness of 50.5D, a breaking strength of 4.18cN / dtex, and a breaking elongation of 48.8%.

[0160] Example 8

[0161] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0162] (1) Preparation of slices;

[0163] Chips: Semi-dull PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0164] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, stretching roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0165] Among them, the side-blowing air adopts the side-blowing air cabinet of Example 2, and the temperature of the side-blowing air flowing through the filter screen is 19.7℃ and the wind speed is 0.67m / s;

[0166] The drafting roll consists of length segments A, B, and C. Length segment C, made of heat-insulating material, is located between length segments A and B, isolating them (to prevent heat exchange). Length segments A, B, and C are coaxial. Length segments A and B are cylindrical, with lengths of 10cm and 10cm respectively. The diameter of length segment A is 0.4cm larger than that of length segment B, which has a diameter of 14cm. Length segment C is frustum-shaped, with the larger end having the same diameter as length segment A and the smaller end having the same diameter as length segment B. Length segment C has a length of 2.5cm. Length segments A, B, and C all contain roller shafts and cylinders fitted onto these shafts. Heaters and temperature sensors are installed inside the cylinders of length segments A and B. These heaters and temperature sensors are electrically connected to slip rings on the corresponding roller shafts, and the slip rings are electrically connected to a control system located outside the drafting roll.

[0167] In the drawing stage of the continuous fiber processing, the drawing roller is kept stationary along the axial direction while the fiber moves along its own length. At the same time, the first guide mechanism and the second guide mechanism are used to control the fiber to reciprocate along the axial direction of the drawing roller, so that the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller.

[0168] After the fiber comes into contact with the drafting roller, it forms a V-shape. The length of the part of the drafting roller's circumferential area in contact with the fiber is L. When it is on the length segment A of the drafting roller, L is 0.6 times the circumference of the length segment A of the drafting roller.

[0169] The first wire guiding mechanism includes a crossbar, a transverse track, a wire guide, and a transverse drive device (i.e., a cylinder). The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The wire guide is fixedly connected to the crossbar.

[0170] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism;

[0171] Two fiber guiding mechanisms are arranged at intervals along the fiber's direction of movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

[0172] The process parameters for preparing bamboo fiber are as follows: the first roller speed is 750 m / min and the temperature is 75℃; the second roller speed is 1350 m / min and the temperature is 26℃; the third roller speed is 3610 m / min and the temperature is 160℃; the guide disc speed is 3570 m / min; the winding speed is 3500 m / min; the fiber moves along its own length at a speed of 760 m / min; the drafting roller rotates around its own central axis at a speed of 760 m / min; the frequency of the fiber's axial reciprocating motion along the drafting roller is 2530 R / min; the temperature of length section B is 90℃; and the temperature of length section A is 195℃.

[0173] No breakage occurred during continuous processing for 98 hours in the preparation process.

[0174] The obtained bamboo fiber has a fineness of 50.3D, a breaking strength of 4.07cN / dtex, and a breaking elongation of 49%.

[0175] Example 9

[0176] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0177] (1) Preparation of slices;

[0178] Chips: Fully matte PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0179] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, stretching roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0180] Among them, the side-blowing air adopts the side-blowing air cabinet of Example 3, and the temperature of the side-blowing air flowing through the filter screen is 20.1℃ and the wind speed is 0.64m / s;

[0181] The drafting roll consists of length segments A, B, and C. Length segment C, made of heat-insulating material, is located between length segments A and B, isolating them (to prevent heat exchange). Length segments A, B, and C are coaxial. Length segments A and B are cylindrical, with lengths of 10cm and 10cm respectively. The diameter of length segment A is 0.3cm larger than that of length segment B, which has a diameter of 12cm. Length segment C is frustum-shaped, with the large end having the same diameter as length segment A and the small end having the same diameter as length segment B. Length segment C has a length of 2.5cm. Length segments A, B, and C all contain roller shafts and cylinders fitted onto these shafts. Heaters and temperature sensors are installed inside the cylinders of length segments A and B. These heaters and temperature sensors are electrically connected to slip rings on the corresponding roller shafts, and the slip rings are electrically connected to a control system located outside the drafting roll.

[0182] In the drawing stage of the continuous fiber processing, the drawing roller is kept stationary along the axial direction while the fiber moves along its own length. At the same time, the first guide mechanism and the second guide mechanism are used to control the fiber to reciprocate along the axial direction of the drawing roller, so that the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller.

[0183] After the fiber comes into contact with the drafting roller, it forms a V-shape. The length of the portion of the drafting roller's circumferential area in contact with the fiber is L. When it is on length segment A of the drafting roller, L is 0.45 times the circumference of length segment A of the drafting roller.

[0184] The first wire guiding mechanism includes a crossbar, a transverse track, a wire guide, and a transverse drive device (i.e., a cylinder). The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The wire guide is fixedly connected to the crossbar.

[0185] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism;

[0186] Two fiber guiding mechanisms are arranged at intervals along the fiber's direction of movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

[0187] The process parameters for preparing bamboo-joint fibers are as follows: Roller speed 850 m / min, temperature 65℃; Roller speed 1400 m / min, temperature 27℃; Roller speed 3700 m / min, temperature 150℃; Guide disc speed 3650 m / min; Winding speed 3600 m / min; Fiber speed along its length 860 m / min; Draft roller rotation speed around its central axis 860 m / min; Fiber reciprocating motion frequency along the draft roller axis 2820 R / min; Temperature of length segment B 110℃; Temperature of length segment A changes periodically, the first cycle as follows... Figure 7 As shown;

[0188] No breakage occurred during continuous processing for 88 hours in the preparation process.

[0189] The obtained bamboo fiber has a fineness of 30.1–30.8D, a breaking strength of 3.98–4.15 cN / dtex, and a breaking elongation of 47.5–49.4%.

[0190] Example 10

[0191] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0192] (1) Preparation of slices;

[0193] Chips: High-gloss PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0194] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, first guide mechanism, stretching roller, second guide mechanism, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber;

[0195] Among them, the side-blowing air adopts the side-blowing air cabinet of Example 4, and the temperature of the side-blowing air flowing through the filter screen is 20.7℃ and the wind speed is 0.60m / s;

[0196] The drafting roll consists of length segments A, B, and C. Length segment C is made of heat-insulating material and is located between length segments A and B, isolating them (to prevent heat exchange). Length segments A, B, and C are coaxial. Length segments A and B are cylindrical structures, with lengths of 10cm and 10cm respectively. The diameter of length segment A is 0.2cm larger than that of length segment B, which has a diameter of 11cm. Length segment C is a frustum-shaped structure, with the large end having the same diameter as length segment A and the small end having the same diameter as length segment B. Length segment C has a length of 2.5cm. Length segments A, B, and C of the drafting roll all contain roller shafts and rollers fitted onto the roller shafts. Heaters and temperature sensors are installed inside the rollers of length segments A and B. The heaters and temperature sensors are electrically connected to slip rings on the corresponding roller shafts of those rollers. The slip rings are electrically connected to a control system located outside the drafting roll.

[0197] In the drawing stage of the continuous fiber processing, the drawing roller is kept stationary along the axial direction while the fiber moves along its own length. At the same time, the first guide mechanism and the second guide mechanism are used to control the fiber to reciprocate along the axial direction of the drawing roller, so that the fiber alternately contacts the circumferential surface of length segment A and length segment B of the drawing roller.

[0198] After the fiber comes into contact with the drafting roller, it forms a V-shape. The length of the portion of the drafting roller's circumferential area in contact with the fiber is L. When it is on length segment A of the drafting roller, L is 0.35 times the circumference of length segment A of the drafting roller.

[0199] The first wire guiding mechanism includes a crossbar, a transverse track, a wire guide, and a transverse drive device (i.e., a cylinder). The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The wire guide is fixedly connected to the crossbar.

[0200] The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism;

[0201] Two fiber guiding mechanisms are arranged at intervals along the fiber's direction of movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

[0202] The process parameters for preparing bamboo-joint fibers are as follows: Roller speed 950 m / min, temperature 60℃; Roller speed 1500 m / min, temperature 24℃; Roller speed 3990 m / min, temperature 145℃; Guide disc speed 3960 m / min; Winding speed 3900 m / min; Fiber speed along its length 960 m / min; Draft roller rotation speed around its central axis 960 m / min; Fiber reciprocating motion frequency along the draft roller axis 2880 R / min; Temperature of length segment B 115℃; Temperature of length segment A changes periodically, the first cycle as follows... Figure 8 As shown;

[0203] No head breakage occurred during continuous processing for 85 hours in the preparation process.

[0204] The obtained bamboo fiber has a fineness of 20.5–21.3D, a breaking strength of 4.09–4.25 cN / dtex, and a breaking elongation of 47.2–50.5%.

[0205] Example 11

[0206] A method for preparing bamboo fiber is basically the same as in Example 10, except that a rotary air control mechanism is not installed in the side blowing cabinet used for side blowing.

[0207] No breakage occurred during continuous processing for 86 hours in the preparation process.

[0208] The obtained bamboo fiber has a fineness of 20.4–21.5D, a breaking strength of 4.05–4.23 cN / dtex, and a breaking elongation of 46.9–50.2%.

[0209] Example 12

[0210] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0211] (1) Preparation of slices;

[0212] Chips: Semi-dull PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0213] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, 15cm diameter drawing roller, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0214] In the heat treatment process, a drafting roller is used. The fiber moves along its own length direction and comes into contact with the circumferential surface of the drafting roller, which rotates around its own central axis. The length of the circumferential area of ​​the drafting roller that comes into contact with the fiber is L, which is 0.2 times the circumference of the drafting roller. The fiber does not move along the axial direction of the drafting roller when it comes into contact with the circumferential surface of the drafting roller.

[0215] The circumferential surface of the drafting roller includes two independent regions, A and B. Regions A and B are two regions that come into contact with the fiber sequentially as the drafting roller rotates around its own central axis. Both regions A and B have four sides, one set of opposite sides being curved and the other set being straight. The straight sides of regions A and B are parallel to the central axis of the drafting roller and have the same length as the drafting roller. The length of the curved side of region A is 18.8 cm, and the length of the curved side of region B is 18.8 cm.

[0216] Regions A and B on the periphery of the stretching roller are separated by heat insulation material to prevent heat exchange, and the distance between the two gaps created by the separation on the periphery is the same; the stretching roller includes the roller shaft and the roller sleeved on the roller shaft. Heaters and temperature sensors are installed at the corresponding positions of regions A and B inside the roller. The heaters and temperature sensors are electrically connected to the slip ring set on the roller shaft. The slip ring is electrically connected to the control system set outside the stretching roller;

[0217] The preparation process parameters are as follows: side blowing temperature is 20.6℃, side blowing speed is 0.35m / s; first roller speed is 900m / min, temperature is 65℃; second roller speed is 1340m / min, temperature is 25℃; third roller speed is 3500m / min, temperature is 140℃; guide disc speed is 3540m / min; winding speed is 3500m / min; fiber speed along its own length at the drafting roller is 910m / min; drafting roller rotation speed around its own central axis is 910m / min; temperature in region B is 25℃, and temperature in region A is 180℃.

[0218] No breakage occurred during continuous processing for 140 hours in the preparation process.

[0219] The obtained bamboo fiber is like Figure 12 As shown, the fineness of bamboo fiber is 20D, the breaking strength is 5cN / dtex, and the breaking elongation is 46%.

[0220] Example 13

[0221] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0222] (1) Preparation of slices;

[0223] Chips: Fully matte PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0224] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, 25cm diameter drawing roller, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0225] In the heat treatment process, a drafting roller is used. The fiber moves along its own length direction and comes into contact with the circumferential surface of the drafting roller, which rotates around its own central axis. The length of the circumferential area of ​​the drafting roller that comes into contact with the fiber is L, which is 0.5 times the circumference of the drafting roller. The fiber does not move along the axial direction of the drafting roller when it comes into contact with the circumferential surface of the drafting roller.

[0226] The circumferential surface of the drafting roller includes two independent regions, A and B. Regions A and B are two regions that come into contact with the fiber sequentially as the drafting roller rotates around its own central axis. Both regions A and B have four sides, one set of opposite sides being curved and the other set being straight. The straight sides of regions A and B are parallel to the central axis of the drafting roller and have the same length as the drafting roller. The length of the curved side of region A is 39.25 cm, and the length of the curved side of region B is 23.55 cm.

[0227] Regions A and B on the periphery of the stretching roller are separated by heat insulation material to prevent heat exchange, and the distance between the two gaps created by the separation on the periphery is the same; the stretching roller includes the roller shaft and the roller sleeved on the roller shaft. Heaters and temperature sensors are installed at the corresponding positions of regions A and B inside the roller. The heaters and temperature sensors are electrically connected to the slip ring set on the roller shaft. The slip ring is electrically connected to the control system set outside the stretching roller;

[0228] The preparation process parameters are as follows: side blowing temperature is 19.0℃, side blowing speed is 0.51m / s; first roller speed is 800m / min, temperature is 75℃; second roller speed is 1560m / min, temperature is 26℃; third roller speed is 4050m / min, temperature is 165℃; guide disc speed is 4030m / min; winding speed is 4000m / min; fiber speed along its own length at the drafting roller is 820m / min; drafting roller rotation speed around its own central axis is 820m / min; temperature in region B is 26℃, and temperature in region A is 195℃.

[0229] No head breakage occurred during the continuous processing for 147 hours in the preparation process.

[0230] The obtained bamboo fiber has a fineness of 70D, a breaking strength of 5.2cN / dtex, and a breaking elongation of 42%.

[0231] Example 14

[0232] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0233] (1) Preparation of slices;

[0234] Chips: High-gloss PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0235] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, 35cm diameter drawing roller, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0236] In the heat treatment process, a drawing roller is used. The fiber moves along its own length direction and comes into contact with the circumferential surface of the drawing roller, which rotates around its own central axis. The length of the part of the circumferential surface of the drawing roller that comes into contact with the fiber is L, which is 0.8 times the circumference of the drawing roller. The fiber does not move along the axial direction of the drawing roller when it comes into contact with the circumferential surface of the drawing roller.

[0237] The circumferential surface of the drafting roller includes two independent regions, A and B. Regions A and B are two regions that come into contact with the fiber sequentially as the drafting roller rotates around its own central axis. Both regions A and B have four sides, one set of opposite sides being curved and the other set being straight. The straight sides of regions A and B are parallel to the central axis of the drafting roller and have the same length as the drafting roller. The length of the curved side of region A is 66 cm, and the length of the curved side of region B is 22 cm.

[0238] Regions A and B on the periphery of the stretching roller are separated by heat insulation material to prevent heat exchange, and the distance between the two gaps created by the separation on the periphery is the same; the stretching roller includes the roller shaft and the roller sleeved on the roller shaft. Heaters and temperature sensors are installed at the corresponding positions of regions A and B inside the roller. The heaters and temperature sensors are electrically connected to the slip ring set on the roller shaft. The slip ring is electrically connected to the control system set outside the stretching roller;

[0239] The preparation process parameters are as follows: side-blowing temperature is 18.1℃, side-blowing speed is 0.56m / s; first roller speed is 600m / min, temperature is 90℃; second roller speed is 1080m / min, temperature is 27℃; third roller speed is 3100m / min, temperature is 180℃; guide disc speed is 3060m / min; winding speed is 3000m / min; fiber speed along its own length at the drafting roller is 610m / min; drafting roller rotation speed around its own central axis is 610m / min; temperature in region B is 27℃, and the temperature in region A changes periodically, the first cycle as follows... Figure 10 As shown;

[0240] No head breakage occurred during continuous processing for 154 hours in the preparation process.

[0241] The obtained bamboo fiber has a fineness of 100–101.8D, a breaking strength of 4.8–5.4 cN / dtex, and a breaking elongation of 39–42%.

[0242] Example 15

[0243] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0244] (1) Preparation of slices;

[0245] Chips: Semi-dull PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0246] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, 16cm diameter drawing roller, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0247] In the heat treatment process, a drafting roller is used. The fiber moves along its own length direction and comes into contact with the circumferential surface of the drafting roller, which rotates around its own central axis. The length of the circumferential area of ​​the drafting roller that comes into contact with the fiber is L, which is 0.4 times the circumference of the drafting roller. The fiber does not move along the axial direction of the drafting roller when it comes into contact with the circumferential surface of the drafting roller.

[0248] The circumferential surface of the drafting roller includes two independent regions, A and B. Regions A and B are two regions that come into contact with the fiber sequentially as the drafting roller rotates around its central axis. Both regions A and B have four sides, one pair of opposite sides being curved and the other pair being straight. The straight sides of regions A and B are parallel to the central axis of the drafting roller and have the same length as the drafting roller. The length of the curved side of region A is 20.1 cm, and the length of the curved side of region B is 20.1 cm.

[0249] Regions A and B on the periphery of the stretching roller are separated by heat insulation material to prevent heat exchange, and the distance between the two gaps created by the separation on the periphery is the same; the stretching roller includes the roller shaft and the roller sleeved on the roller shaft. Heaters and temperature sensors are installed at the corresponding positions of regions A and B inside the roller. The heaters and temperature sensors are electrically connected to the slip ring set on the roller shaft. The slip ring is electrically connected to the control system set outside the stretching roller;

[0250] The preparation process parameters are as follows: side-blowing temperature is 21.2℃, side-blowing speed is 0.30m / s; first roller speed is 950m / min, temperature is 70℃; second roller speed is 1360m / min, temperature is 25℃; third roller speed is 3500m / min, temperature is 150℃; guide disc speed is 3470m / min; winding speed is 3400m / min; fiber speed along its own length at the drafting roller is 970m / min; drafting roller rotation speed around its own central axis is 970m / min; temperature in region B is 135℃, and the temperature in region A changes periodically, the first cycle as follows... Figure 10 As shown;

[0251] No head breakage occurred during the continuous processing for 136 hours in the preparation process.

[0252] The obtained bamboo fiber has a fineness of 15-16.4D, a breaking strength of 4.7-5.3cN / dtex, and a breaking elongation of 41-45%.

[0253] Example 16

[0254] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0255] (1) Preparation of slices;

[0256] Chips: Fully matte PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0257] (2) The slices are passed through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, 20cm diameter drawing roller, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0258] In the heat treatment process, a drafting roller is used. The fiber moves along its own length direction and comes into contact with the circumferential surface of the drafting roller, which rotates around its own central axis. The length of the circumferential area of ​​the drafting roller that comes into contact with the fiber is L, which is 0.6 times the circumference of the drafting roller. The fiber does not move along the axial direction of the drafting roller when it comes into contact with the circumferential surface of the drafting roller.

[0259] The circumferential surface of the drafting roller includes two independent regions, A and B. Regions A and B are two regions that come into contact with the fiber sequentially as the drafting roller rotates around its own central axis. Both regions A and B contain four sides, one set of opposite sides being curved and the other set being straight. The straight sides of regions A and B are parallel to the central axis of the drafting roller and have the same length as the drafting roller. The length of the curved side of region A is 31.4 cm, and the length of the curved side of region B is 18.84 cm.

[0260] Regions A and B on the periphery of the stretching roller are separated by heat insulation material to prevent heat exchange, and the distance between the two gaps created by the separation on the periphery is the same; the stretching roller includes the roller shaft and the roller sleeved on the roller shaft. Heaters and temperature sensors are installed at the corresponding positions of regions A and B inside the roller. The heaters and temperature sensors are electrically connected to the slip ring set on the roller shaft. The slip ring is electrically connected to the control system set outside the stretching roller;

[0261] The preparation process parameters are as follows: side-blowing temperature is 19.5℃, side-blowing speed is 0.43m / s; first roller speed is 850m / min, temperature is 80℃; second roller speed is 1560m / min, temperature is 26℃; third roller speed is 4000m / min, temperature is 160℃; guide disc speed is 3960m / min; winding speed is 3900m / min; fiber speed along its own length at the drafting roller is 870m / min; drafting roller rotation speed around its own central axis is 870m / min; temperature in region B is 145℃, and the temperature in region A changes periodically, the first cycle as follows... Figure 11 As shown;

[0262] No breakage occurred during continuous processing for 140 hours in the preparation process.

[0263] The obtained bamboo fiber has a fineness of 40–40.9D, a breaking strength of 4.7–5.5 cN / dtex, and a breaking elongation of 38–43%.

[0264] Example 17

[0265] A method for preparing bamboo fiber, the specific steps of which are as follows:

[0266] (1) Preparation of slices;

[0267] Chips: High-gloss PA6 chips with a relative viscosity of 2.5, produced by Fujian Hengshen Synthetic Fiber Technology Co., Ltd.

[0268] (2) The slices are passed sequentially through a screw extruder, melt pipe, assembly, spinneret, side blower, oil nozzle, tunnel, pre-networker, first roller, first guide, 32cm diameter drawing roller, second guide, second roller, third roller, main networker, guide disc and winding head to obtain bamboo fiber.

[0269] In the heat treatment process, a drafting roller is used. The fiber moves along its own length direction and comes into contact with the circumferential surface of the drafting roller, which rotates around its own central axis. The length of the circumferential area of ​​the drafting roller that comes into contact with the fiber is L, which is 0.7 times the circumference of the drafting roller. The fiber does not move along the axial direction of the drafting roller when it comes into contact with the circumferential surface of the drafting roller.

[0270] The circumferential surface of the drafting roller includes two independent regions, A and B. Regions A and B are two regions that come into contact with the fiber sequentially as the drafting roller rotates around its own central axis. Both regions A and B contain four sides, one set of opposite sides being curved and the other set being straight. The straight sides of regions A and B are parallel to the central axis of the drafting roller and have the same length as the drafting roller. The length of the curved side of region A is 56.52 cm, and the length of the curved side of region B is 22 cm.

[0271] Regions A and B on the periphery of the stretching roller are separated by heat insulation material to prevent heat exchange, and the distance between the two gaps created by the separation on the periphery is the same; the stretching roller includes the roller shaft and the roller sleeved on the roller shaft. Heaters and temperature sensors are installed at the corresponding positions of regions A and B inside the roller. The heaters and temperature sensors are electrically connected to the slip ring set on the roller shaft. The slip ring is electrically connected to the control system set outside the stretching roller;

[0272] The preparation process parameters are as follows: side-blowing temperature is 18.0℃, side-blowing speed is 0.61m / s; first roller speed is 650m / min, temperature is 85℃; second roller speed is 1150m / min, temperature is 27℃; third roller speed is 3200m / min, temperature is 185℃; guide disc speed is 3160m / min; winding speed is 3100m / min; fiber speed along its own length at the drafting roller is 770m / min; drafting roller rotation speed around its own central axis is 770m / min; temperature in region B is 155℃, and the temperature in region A changes periodically, the first cycle as follows... Figure 11 As shown;

[0273] No head breakage occurred during continuous processing for 164 hours in the preparation process.

[0274] The obtained bamboo fiber has a fineness of 150–153.4D, a breaking strength of 4.9–5.8 cN / dtex, and a breaking elongation of 36–41%.

Claims

1. A method for preparing bamboo fiber, characterized in that, In the continuous fiber processing, a portion of the fiber length is heat-treated during the stretching stage, and the heat treatment temperature is controlled to be higher than the glass transition temperature of the fiber but lower than the melting point of the fiber, thus producing bamboo fiber; or, in the continuous fiber processing, the entire length of the fiber is heat-treated during the stretching stage, and the heat treatment temperatures for different lengths are not completely the same, and the heat treatment temperature is controlled to be higher than the glass transition temperature of the fiber but lower than the melting point of the fiber, thus producing bamboo fiber. The heat treatment uses a drawing roller, which includes two independent length segments, A and B. While the fiber moves along its own length, the drawing roller remains stationary along the axial direction. The fiber reciprocates along the axial direction of the drawing roller, thereby alternately contacting the circumferential surfaces of length segment A and length segment B. The temperature of length segment A is the same as the heat treatment temperature, but the temperature of length segment A is higher than the temperature of length segment B.

2. The method for preparing bamboo fiber according to claim 1, characterized in that, Both length sections A and B of the drafting roll contain a roller shaft and a roller sleeved on the roller shaft. Heaters and temperature sensors are installed inside the rollers of both length sections A and B. The heaters and temperature sensors are electrically connected to slip rings set on the roller shafts corresponding to the rollers. The slip rings are electrically connected to a control system set outside the drafting roll.

3. The method for preparing bamboo fiber according to claim 2, characterized in that, Between length section A and length section B of the drawing roller, there is also a length section C, which is made of heat insulation material; length sections A, B, and C are coaxial; length sections A and B are cylindrical structures with a length range of 10-20cm, the diameter of length section A is 0.1-0.5cm larger than that of length section B, and the diameter of length section B ranges from 7-15cm; length section C is a frustum-shaped structure with the same diameter at the large end as length section A and the same diameter at the small end as length section B, and its length ranges from 2-4cm.

4. The method for preparing bamboo fiber according to claim 1, characterized in that, The reciprocating motion of the fiber along the axial direction of the drawing roller is achieved by two guiding mechanisms, namely the first guiding mechanism and the second guiding mechanism. The first guide wire mechanism includes a crossbar, a transverse track, a guide wire, and a transverse drive device. The crossbar and the transverse track are both parallel to the central axis of the drafting roller. The crossbar is slidably connected to the transverse track. The transverse drive device is used to drive the crossbar to reciprocate on the transverse track. The guide wire is fixedly connected to the crossbar. The structure of the second guidewire mechanism is the same as that of the first guidewire mechanism; Two fiber guiding mechanisms are arranged at intervals along the direction of fiber movement and distributed on both sides of the drafting roller; the fiber passes through the guides of both fiber guiding mechanisms simultaneously.

5. The method for preparing bamboo fiber according to claim 1, characterized in that, The process of preparing bamboo fiber includes a side blowing process, which uses a side blowing cabinet. The side blowing cabinet includes an air inlet pipe, an air valve, a filter screen, a side blowing screen, a cabinet body, and a rotary air control mechanism. The rotary wind control mechanism consists of a motor, a rotating column, and blades. The motor is connected to the rotating column and is used to drive the rotating column to rotate around its own central axis at a uniform or variable speed. The rotating column has n strip slots parallel to the central axis of the rotating column, where n is a positive integer greater than 2. The number of blades is the same as the number of strip slots, and each blade is installed in a different strip slot. At least two blades have holes, and the number of holes is different; and / or at least two blades have embedded heating wires, which are electrically connected to a fixed power supply through a collector ring set on a rotating column. The rotary air control mechanism is located inside the cabinet and above the filter screen, dividing the space above the filter screen inside the cabinet into upper and lower parts, which are connected by holes on the blades.

Images