KR100486816B1 - Process for preparing lyocell multi-filament having better strength conversion ratio - Google Patents

Abstract

The present invention is a method for producing a lyocell filament having a constant number of entanglement and entanglement as well as the dispersion effect of the oil by passing the interlacing nozzle through the interlacing nozzle before and after the emulsion treatment of lyocell filament yarn, lyocell filament produced by this method Sasa improves the focusability through air entanglement, improves flatness, secures stable fiber structure, improves flammability, and manufactures lyocell yarn with very high utilization rate compared to yarn of tire cord after combustible and heat-treated. It is done.

Description

Process for preparing lyocell multi-filament having better strength conversion ratio

The present invention relates to a method for producing a lyocell filament excellent in post-processing, and more particularly, through the interlacing nozzle before and after the tanning treatment to increase the dispersing effect of the emulsion, impart a regular entanglement to improve the post-process workability and strong The present invention relates to a method for producing a lyocell filament yarn which can be used for tire cords by improving the utilization rate.

In general, the interlacing technique has been used as a method for making a yarn formed of mixed fibers, entanglement or loops, and wool by passing air through a composite yarn or a filament yarn.

The interlacing technique causes the filaments to be entangled or interlaced and twisted by hitting the air in an oblique direction to the filament traveling direction, where the air is filament bundles according to the tension of the yarn and the speed and quantity of the yarn. It is used as the main means of horn fiber, and it is used for horn fiber during spinning, horn fiber with twisted yarn and untwisted yarn, and it is also used with flammable equipment during false twisting. . In addition, it improves the focusability of the yarn, thereby improving the flatness and contribute to the improvement of flammability workability.

Recently, interlacing technology has been developed as a new material having different physical properties by compounding and burning natural staple yarns such as synthetic fiber, wool, cotton, and viscose acrylic yarn, and is also included in a composite yarn manufacturing machine that produces these materials.

In addition, this interlacing technology is also used in the manufacturing process of polyamide crimped yarn, ie, BCF (Bulked Continuous Filament) for carpets, which improves workability and dyeing unevenness of the post process.

In addition, the interlacing technology has a great advantage that the purpose is to improve the weaving and the manufacturing cost is less than the combustible or sizing (sizing) of the filament yarn.

However, with the recent appearance of the microfiber (mirofilament), the optimum conditions for the development of the fiber suitable for the use of the product has to be presented, and also have a number of problems to be solved technically.

For example, interlacing technology is also important in the manufacture of fibers such as rayon, polyester, nylon and the like used in the field of tire cords or industrial materials. At this time, the interlace technology is mainly used for the purpose of improving the flatness of the yarn to improve the focusing.

However, unlike apparel fields where color expression and handle are important, the strength and modulus of yarns, physical properties after post-processing such as twisting and heat treatment, workability improvement and adhesion, fatigue resistance, and strong utilization rate of post-processes In the case of tire cords or textiles used in the field of industrial materials to determine commodity value, the interlacing spacing should be regular. In the case of interlacing according to the prior art, the spacing is irregular. It has a problem that causes it to occur.

The present invention has been made in order to solve the above problems, by using an interlace nozzle before and after the tanning process, using fibers that have been removed from the cellulose solution prepared by the NMMO / water mixed solvent, the solvent is completed, Enhances dispersion effect, improves flatness of yarn and improves workability of post-processing and post-processing, thereby making lyocell tire cord and similar industrial lyocell filament manufacturing method with higher utilization rate than yarn after flammability and heat treatment The purpose is to provide.

The present invention for achieving the above object, the filament extruded through the spinning nozzle is passed through the air layer to reach a coagulation bath to solidify; The filament is passed through the coagulation bath and washed with a washing bath, the solvent in the fiber is dropped and solidified; The filament, which has been washed with water after passing through the washing bath, has a first interlacing nozzle in front of the first emulsion treatment apparatus or a first interlacing nozzle in the rear of the first emulsion treatment apparatus to a first front and rear of the primary emulsion treatment apparatus. Imparting entanglement while passing through the two interlace nozzles; And winding the filament imparted by the first or second interlace nozzle through a drying apparatus and a secondary tanning apparatus.

In addition, it is preferable to further include a step of providing a third interlace nozzle to impart entanglement to the filament before being wound through the secondary emulsion treatment apparatus.

In addition, it is preferable that the first, second, and third interlace maintain an air pressure of 0.5 to 4.0 kg / cm ² .

In addition, it is preferable to improve the focusing property and stabilize the internal structure of the yarn by setting the number of entanglements per meter of the filament to 2 to 40 times.

And, the step of producing the raw cord for the tire cord by using a direct twisting machine to comb each of the two filaments manufactured through the above manufacturing step and at the same time combined. Weaving the raw cord using a high speed weaving machine; After immersing the woven fabric in a dipping solution, it is preferable to further include the step of curing to prepare a Dip Cord with a resin layer attached to the surface of the raw cord.

In addition, the strength of the Dip Cord is preferably having a physical property in the range of 14.0 ~ 25.0kg.

In addition, it is preferable that the strong utilization ratio of the yarn of the Dip Cord is 75 to 98%.

In the present invention, an interlace nozzle was used immediately before the winding step after drying for the purpose of improving the strong utilization rate through the improvement of the flatness (comparative example). However, the flatness through entanglement was improved, but it showed problems in appearance irregularity of filament yarn and physical properties after post-processing by winding immediately after interlacing. To solve this problem, the interlacing nozzle was moved before the drying step as shown in FIG. The purpose of this study was to investigate the effect of dispersion and filament concentration and flatness improvement.

The present invention is characterized in that the cutting load of the yarn is in the range of 10.0 ~ 20.0kg, the elongation is 3 to 15%, the strength of the dip cord yarn after heat treatment compared to the yarn has a high utilization of lyocell filament for the tire cord 75 to 98% There is provided a method of preparing the same. Hereinafter, the present invention will be described in more detail. In order to manufacture a lyocell filament as in the present invention, pulp having high purity of cellulose should be used. In order to manufacture high quality cellulose fiber, it is preferable to use the thing with high alpha cellulose content. The reason for this is that excellent physical properties can be expected by high orientation structure and high crystallization using cellulose molecules having high polymerization degree. Therefore, the cellulose used in the present invention used a DP 1,200, soft wood pulp having an α-cellulose content of 93% or more.

NMMO is known as a solvent that has good solubility in cellulose and is not toxic. Here, NMMO uses monohydrate adjusted to the level of about 87%, because the presence of water is essential to open the pore of crystalline cellulose with high solubility. A small amount of 3,4,5-Trihydroxybenzoic acid propyl ester (hereinafter referred to as propyl gallate) was added to suppress the thermal decomposition of the NMMO and to ensure the safety of the cellulose solution.

In order to dissolve cellulose in NMMO, external force such as shear is essential. In the present invention, cellulose is dissolved through a twin screw extruder. The cellulose solution described above has an orifice diameter of 100 to 300 µm and an orifice length of 200. After spinning through a nozzle having a ratio of orifice diameters and lengths of about 2 to 8 μm at ˜2,400 μm, lyocell filaments can be obtained through the process shown in FIG. 1. Producing a lyocell filament through the process as shown in Figure 1 is a feature of the present invention and a detailed description is as follows.

First, the solution extruded from the spinning nozzle 1 passes through an air gap in the vertical direction and solidifies in the coagulation bath 2. At this time, the air gap is spun in the range of about 10 to 300 mm in order to obtain a dense and uniform fiber and to impart a smooth cooling effect.

After that, the coagulant that has passed through the coagulation bath 2 passes through the water washing tank 3. At this time, the temperature of the coagulation bath 2 and the water washing tank 3 is maintained at about 0 to 30 ° C. in order to prevent the deterioration of physical properties due to the formation of pores and the like in the fibrous structure due to the rapid desolvent.

Then, the fiber passing through the water washing tank (2) passes through the squeegee roller (4) for water removal, and then passes through the primary emulsion treatment apparatus (5). The filament yarn obtained here has high flatness due to the effect of the squeegee roller 4 and the primary oil treatment apparatus 5, and contains the oil agent and water together.

In order to improve the flatness and improve the focusability, and to open the fibers to facilitate the dispersion of the oil agent, the second interlace nozzle 6b or the third interlace nozzle 6c is passed. In addition, for this purpose, together with the 2nd interlace nozzle 6b or the 3rd interlace nozzle 6c, it used together in the position of the 1st interlace nozzle 6a. The shape of each interlace nozzle 6a, 6b, 6c used at this time is as shown in FIG.

At this time, the air is introduced to hit the filament through the hole (6 ') is to be twisted at random as the filaments are opened.

Here, the tension of the yarns before and after each interlace nozzle 6b, 6c and the air pressure supplied through both holes 6 'are important factors for determining the quality of the final yarn. In the present invention, the tension is fixed to the minimum, and The air pressure of the interlace nozzles 6b and 6c was supplied at 0.5 to 4.0 kg / cm ² .

Thereafter, the filament yarns having passed through the second and third interlacing nozzles 6b and 6c before and after the primary tanning agent 5 are dried while passing through the drying unit 7. At this time, the drying temperature and drying method have a great influence on the post process and the physical properties of the filament. In the present invention, the drying temperature was adjusted so that the process water content could be about 8 to 12%.

Here, the filament passing through each interlace nozzle 6b and 6c and undergoing a drying process exhibits a uniform drying effect by improving flatness through interlacing, and slightly unentangles the entanglement provided by each interlace nozzle 6b and 6c. It can be seen that.

And the filament which passed the drying apparatus 7 is finally wound up by the winding machine 9 via the secondary emulsion processing apparatus 8. Here, the first interlace nozzle 6a may be further provided between the drying apparatus 7 and the winder 9.

The filament passed through the spinning, solidification, washing, interlacing, drying, and winding processes in the above manner is provided as a tire cord and a filament yarn for industrial materials. Two wound filament yarns were twisted and twisted together with a direct weaving machine to produce 'Raw Cords' for tire cords, and after immersing the prepared 'Raw Cords' in dipping solution, curing and 'Raw Cords' Tire cord 'Dip Cord' having a resin layer on the surface thereof was prepared and evaluated for physical properties.

Hereinafter, the present invention will be described in detail with reference to Comparative Examples and Examples, and the following evaluation methods are used in Comparative Examples and Examples.

(a) the number of intersections

After running the filament yarn through the entanglement measuring device, the number of entanglements per unit length in the lateral direction was measured by inserting a sharp pin in the middle of the traveling yarn, where the unit is expressed as the number of entanglements per meter.

(b) strength (kgf) and elongation (%)

After drying at 107 ° C. for 2 hours, the sample was measured at 250 mm and a tensile speed of 300 m / min using an Instron low speed tensile tester. Elongation at specific load represents the elongation at the point of 4.5 kg load.

(c) strong utilization rate

After drying for 2 hours at 107 ° C, the filament yarn was measured by 250mm of tensile strength and 300m / min of tensile strength using Instron's low speed extension type tester. It shows the ratio of the strength of the dip cord obtained by.

Strength utilization (%) = Dip Cord Strength / (A yarn strength + B yarn strength) × 100

EXAMPLES 1-6

Cellulose solution prepared using pulp with a degree of polymerization (DP _W ) of 1200 (α-cellulose content; 97%), NMMO.1H ₂ O, and propyl gallate was used in an amount of 0.035wt%. At this time, the concentration of cellulose was 9-12%, the number of orifice was 1,000, the orifice diameter was 150 μm, the solution discharged from the spinning nozzle having a ratio (L / D) of 4 to 8 and an outer diameter of 100 mmΦ. The air gap was cooled to have a length of 30 to 100 mm, the spinning speed was 150 m / min, and the final filament fineness was 1,500 denier. The coagulation solution temperature was adjusted to 0-30 ° C., the concentration was 80% water, and the NMMO 20%. The temperature and concentration of the coagulation solution were continuously monitored using a refractometer. The filament which escaped the coagulation bath removes the remaining NMMO by washing with water. Winding was carried out using a second and third interlace nozzle before or after the primary tanning apparatus while changing the air pressure to 0.5 to 4.0 kg / cm ² . The OPU of the wound yarn filament was adjusted to 0.3 to 0.8%. The conditions and the number of interlacing nozzles of the interlacing nozzles of the filaments at this time are shown in Table 1, and the produced filament yarns were subjected to direct twisting with 47 times / 10 cm in the Z direction and 47 times / 10 cm in the S direction. Dip Cord was prepared by thermally immersing in a conventional RFL solution after the twisted in combination. Yarn physical properties and dip cord physical properties at this time are shown in Table 2.

TABLE 1

             Classification Condition Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Filament denier 1510 1500 1530 1510 1520 1520 Air pressure (kg / cm2) 0.5 2.0 3.5 0.5 2.0 3.5 Ducts per meter 3 11 25 4 10 23 Interlaced Position Immediately after the first emulsion Immediately after the first emulsion Immediately after the first emulsion Just before the first emulsion Just before the first emulsion Just before the first emulsion

TABLE 2

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Filament Yarn Properties Strong (kgf) 10.7 10.8 10.7 10.7 10.6 10.6 Strength (g / d) 7.1 7.1 7.0 7.2 7.0 7.0 Intermediate Elongation (%) 1.2 1.1 1.3 1.2 1.3 1.3 Elongation at break (%) 4.7 4.7 5.0 4.8 4.9 5.0 Dip Cord Properties Strong (kgf) 18.5 19.9 20.4 18.7 19.3 19.8 Intermediate Elongation (%) 1.5 1.7 1.6 1.8 1.7 1.6 Elongation at break (%) 5.7 5.8 5.7 5.9 5.8 5.7 Strength utilization rate compared to yarn (%) 86.4 92.0 95.1 87.6 91.2 93.3

EXAMPLES 7-12

The solution was prepared using the method similar to Examples 1-6. The coagulation solution temperature was adjusted to 0-30 ° C., the concentration was 80% water, and the NMMO 20%. The temperature and concentration of the coagulation solution were continuously monitored using a refractometer. The filament which escaped the coagulation bath removes the remaining NMMO by washing with water. The first and second interlacing nozzles were used before or after the first tanning treatment device, and the first interlacing nozzles were used together immediately before winding, thereby winding the air pressure at 0.5 to 4.0 kg / cm ² . In Examples 11 and 12, the air pressure of each interlaced nozzle was treated differently. The OPU of the wound yarn filament was adjusted to 0.3-0.8%, and the interlacing conditions and the number of interlacing of each filament at this time are shown in Table 3, and the filament yarn was 47 times / 10cm in the Z direction using a direct yarn. Dip Cord was prepared by twisting the upper edge and the upper edge in two directions of 47 times / 10cm in the S direction, followed by immersion in a conventional RFL solution and heat treatment. Yarn physical properties and dip cord physical properties at this time are shown in Table 4.

TABLE 3

      Classification condition Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Filament denier 1500 1505 1510 1500 1520 1500 Air pressure (kg / cm2) Primary-0.52 Primary-0.5 1.51.5 0.50.5 1.51.5 1.50.5 0.51.5 Ducts per meter 9 28 11 31 19 20 Interlaced Position Just before the first emulsion + immediately before winding Just before the first emulsion + immediately before winding Immediately after the first emulsion + immediately before winding Immediately after the first emulsion + immediately before winding Immediately after the first emulsion + immediately before winding Immediately after the first emulsion + immediately before winding

TABLE 4

Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Filament Yarn Properties Strong (kgf) 10.5 10.8 10.6 10.7 10.5 10.5 Strength (g / d) 7.0 7.2 7.0 7.1 6.9 7.0 Intermediate Elongation (%) 1.3 1.2 1.1 1.2 1.0 1.3 Elongation at break (%) 4.9 4.8 4.7 4.8 4.6 5.0 Dip Cord Properties Strong (kgf) 18.2 19.0 18.2 18.8 17.9 17.8 Intermediate Elongation (%) 1.6 1.8 1.7 1.7 1.6 1.6 Elongation at break (%) 5.8 6.0 5.9 5.8 5.7 5.7 Strength utilization rate compared to yarn (%) 86.8 87.7 86.0 88.2 85.5 84.9

Comparative Examples 1 to 6

A solution of the same composition as in Example was prepared. The coagulation solution temperature was adjusted to 0-30 ° C., the concentration was 80% water, and the NMMO 20%. The temperature and concentration of the coagulation solution were continuously monitored using a refractometer. The filament exiting the coagulation bath is entangled by removing residual NMMO through a water washing process, removing water through drying, and passing the secondary emulsion treatment device while changing the pressure of each interlace nozzle to 0.5 to 4.0 kg / cm ² . Was given and wound up. The interlacing conditions and the number of interlacing conditions of the filaments at this time are shown in Table 5, and the filament yarns were fabricated with a direct twisting machine in the lower edge of 47 times / 10cm in the Z direction, and the upper edges of 47 times / 10cm in the S direction. Dip Cord was prepared by heat treatment by immersion in a conventional RFL solution after the twisting. Yarn physical properties and dip cord physical properties at this time are shown in Table 6.

TABLE 5

           Classification Condition Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Filament denier 1510 1520 1500 1520 1530 1510 Air pressure (kg / cm2) 0 0.5 1.0 2.0 3.0 3.5 Ducts per meter 2 3 7 14 22 29 Interlaced Position × after drying after drying after drying after drying after drying

TABLE 6

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Filament Yarn Properties Strong (kgf) 10.7 10.8 10.4 10.6 10.7 10.3 Strength (g / d) 7.1 7.1 6.9 7.0 7.0 6.8 Intermediate Elongation (%) 1.1 1.2 1.1 1.0 1.1 1.0 Elongation at break (%) 4.3 4.5 4.2 4.2 4.4 4.1 Dip Cord Properties Strong (kgf) 16.7 17.1 16.4 16.6 16.8 16.0 Intermediate Elongation (%) 1.8 1.9 1.7 1.8 1.6 1.6 Elongation at break (%) 5.7 5.6 5.4 5.3 5.4 5.2 Strength utilization rate compared to yarn (%) 78.0 79.2 79.4 78.1 78.4 77.8

Thus, the lyocell filament manufacturing method according to the present invention uses a cellulose solution prepared with an NMMO / water mixed solvent, by using a second or third interlaced nozzle before and after emulsion treatment and a first interlaced nozzle before winding. , Improve the dispersing effect of emulsion, improve the flatness of yarn, improve the workability of the focusing process and the post-process, and thus the strong utilization rate of yarn compared to the yarn after flammability and heat treatment, tire cord and similar industrial lyocell It is effective to provide filament.

1 is a schematic diagram of a spinning process for producing a high strength lyocell filament for a tire cord of the present invention.

2 is a sectional view of principal parts of an interlace nozzle used in the present invention.

Claims (6)

Filament extruded through the spinning nozzle is passed through the air layer to reach the coagulation bath to solidify; The filament is passed through the coagulation bath and washed with a washing bath, the solvent in the fiber is dropped and solidified; The filament, which has been washed with water after passing through the washing bath, has a first interlacing nozzle in front of the first emulsion treatment apparatus or a first interlacing nozzle in the rear of the first emulsion treatment apparatus to a first front and rear of the primary emulsion treatment apparatus. Imparting entanglement while passing through the two interlace nozzles; And winding up the filament imparted by the first or second interlacing nozzles through a drying apparatus and a secondary emulsion treatment apparatus. The method of claim 1, And providing a third interlacing nozzle to impart entanglement to the filament before winding it through the secondary emulsion treatment apparatus. The method according to claim 1 or 2, The first, second, third interlace method for producing a lyocell filament, characterized in that for maintaining the air pressure between 0.5 to 4.0kg / cm ² . The method of claim 3, wherein A method for producing a lyocell filament, characterized in that the number of entanglements per meter of the filament is 2 to 40 to improve focusing and stabilize the internal structure of the yarn. The method of claim 1, A method of manufacturing a tire cord using a lyocell filament, characterized in that the strength of the deep cord manufactured using the filament obtained from the manufacturing step has physical properties in the range of 14.0 to 25.0 kg. The method of claim 5, The method of manufacturing a tire cord using a lyocell filament, characterized in that the strong utilization rate of the deep cord is 75 to 98% of the yarn.