JP2011063906A - Spinneret and method for producing filament yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spinneret having excellent spinning stability, giving little fineness unevenness among single fibers and among yarns, and exhibiting remarkable effects for obtaining yarns having good quality such as thickness unevenness, strength and elongation of the yarn when producing a multifilament. <P>SOLUTION: The spinneret having arranged spinning holes for spinning a polymer as a filament yarn satisfies the following requirements (1) to (4): (1) the spinning hole is at least constituted of an introducing hole, and an extruding hole arranged at the downstream side of the introducing hole in the spinning route of the polymer, and for extruding the polymer from the lower surface of the spinneret; (2) the spinneret is at least constituted of an upper plate in which the introducing holes are arranged, and a lower plate in which the extruding holes are arranged; (3) the cross section area of the introducing hole in the direction orthogonal to the spinning route direction of the polymer is larger than that of the extruding hole in the direction orthogonal to the spinning route direction of the polymer; and (4) the heat conductivity of the upper plate is smaller than that of the lower plate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spinneret and a method for producing a filament yarn.

  Filament yarns composed of polyester and polyamide, such as polyester fiber and nylon fiber, are generally equipped with a spinning method, that is, a thermoplastic polymer such as polyester or polyamide is melted and supplied to a spinning pack. After spinning from the spinneret as a filament yarn, cooling and solidifying with an air flow, etc., if necessary, bundling or applying an oil agent, etc., once taken up with a roller, etc. Etc. are manufactured through a process such as winding. The above-described drawing, heat treatment, and the like are performed when the filament yarn spun from the spinneret is cooled and solidified by an air current or the like and then passed through a heating tube or the like. It may be performed in a process.

  On the other hand, filament yarn composed of acrylic fiber, polyacrylonitrile, etc. is generally equipped with a spinning pack, that is, a polymer such as polyacrylonitrile is dissolved in a solvent and supplied to a spinning pack as a polymer solution. After being spun into a coagulation bath as a filament yarn from a spinneret and solidified, it is manufactured through a process such as washing, drawing, drying, or applying an oil as necessary, and then winding. As described above, the filament yarn is spun into a coagulation bath from the spinneret and solidified, as described above, the filament yarn is directly spun into the coagulation bath and solidified, and the filament yarn from the spinneret is solidified. A method of spinning in a gas and then solidifying by passing through a coagulation bath is known. Generally, the former is called a wet spinning method and the latter is called a dry wet spinning method.

  In the solution spinning method, a polymer is dissolved in a volatile solvent, supplied to a spinning pack as a polymer solution, spun into a heated gas as a filament yarn from a spinneret equipped in the spinning pack, and the solvent is evaporated. There is also a method of producing a filament yarn after being solidified by such a method, once taken up by a roller or the like, subjected to drawing or the like as necessary, and then taken up. This method is generally called a dry spinning method, and this method is adopted for polyurethane fibers and the like.

  In the present specification, hereinafter, the molten polymer used in the melt spinning method and the polymer solution dissolved in the polymer solvent used in the solution spinning method will be collectively referred to as a polymer.

  In these spinning methods, the spinneret is generally recognized as an extremely important device for accurately measuring the shape, thickness, and weight of the filament yarn and stably spinning.

  On the other hand, in the production of filament yarn, many developments such as high speed and multiple yarns have been made with the aim of improving productivity. For example, in the field of the melt spinning method, development of high speed has been promoted mainly on polyester fiber, and initially, unoriented undrawn yarn (hereinafter referred to as UDY: Un Drawn Yarn) in a spinning process up to a spinning speed of about 1000 m / min. ) Was obtained in a separate process, and a method for obtaining oriented oriented yarn (FOY: Full Oriented Yarn) was mainstream. However, in the 1970s, the winding speed was increased. Direct spinning drawing (DSD: Direct Spin Draw) has been developed, in which spinning and drawing are directly connected to approximately 5000 m / min to obtain a drawn yarn in one step. Further, a partially oriented yarn (hereinafter referred to as POY: Partially Oriented Yarn) is obtained in a spinning process with a spinning speed of about 3000 to 5000 m / min, and stretched and false twisted in a separate process. A rational technique has been developed that can provide false-twisted yarn (hereinafter DTY: Draw Textured Yarn). Furthermore, OSY (One Step Yarn) with a spinning speed of 5000 m / min, which does not require stretching, was developed. Spin winding at 8000 m / min in the late 1980s and 10,000 m / min in the 1990s was realized. ing.

  Similarly, with the aim of improving productivity, development of a multi-filament that allows a plurality of filament yarns to be spun from a single spinneret has been actively conducted.

  On the other hand, in recent years, the needs for filament yarn have diversified, and many special filament yarns with various functions have been developed and put on the market. For example, in the field of clothing, the single yarn has an irregular cross section for the purpose of giving fine texture, soft filaments, etc., and improving the water absorption and quick drying, and changing the glossiness. Improvements such as modifying polymers with the aim of imparting new functionality such as realization of dyeing with excellent sharpness have been made. Similarly, in the industrial field, in addition to making single yarn finer, multifilament, and single yarn irregular cross-section, new functionalities such as high strength, high elasticity, weather resistance, flame resistance, etc. Improvements such as targeted polymer modification have been made. Furthermore, recently, attempts to provide a combination of a plurality of functionalities as described above have begun actively.

  However, special filament yarns as described above are high-functional varieties having excellent functionality, but also difficult-to-spin varieties. Therefore, it is extremely difficult to produce special filament yarns with high productivity, specifically, at high speed, multiple yarns, or high speed and multiple yarns, and the special filament yarns are low in cost. As a result, it has been a hindrance to the expansion of sales and applications of special filament yarns.

  This problem will be described by taking as an example the case where the filament yarn is made into a single yarn fineness and multifilament in the field of melt spinning. When the fineness of the single yarn is reduced, each single yarn of the filament yarn is easily solidified in the vicinity of the spinneret, and reaches a predetermined take-up speed in the vicinity of the spinneret. Therefore, according to the knowledge of the present inventors, a large accompanying flow is formed around each single yarn of the filament yarn from the vicinity of the spinneret. In addition, when the production speed of the filament yarn is increased, an increasingly large accompanying flow is formed in the vicinity of the spinneret. As a result, the flow of airflow in the vicinity of the spinneret becomes extremely complicated and easily disturbed. Then, the size of the device and the non-uniformity of the cooling airflow are triggered, and locally, the cooling airflow is directly drawn into the vicinity of the spinneret by each single filament yarn. The spinneret is locally cooled and large temperature spots are formed on the spinneret. As a result, large spots appear in the discharge amount of the polymer in each discharge hole of the spinneret that spins each single yarn of the filament yarn. This led to large fineness irregularities between the filament yarns spun from the die, which was a big problem.

  This problem also becomes a serious problem in the case of filament yarns having a single-shaped irregular cross section, filament yarns made of modified polymers, and the like. For example, in a filament yarn having a single-filament modified cross section, the surface area, air resistance, etc. of the single yarn are larger than those of a round cross section, so that each single filament yarn is easily solidified in the vicinity of the spinneret. Further, since the surface area, air resistance, etc. of the single yarn are larger than those of the round cross section, the size of the accompanying flow formed around each single yarn of the filament yarn is likely to be large. In addition, for example, in thermoplastic polymers, copolymerization is an example of a method for modifying the polymer. Generally, when copolymerization is performed, the molecular structure is disturbed, so that the strength and elongation of the filament yarn are reduced. It tends to be low. For this reason, in many cases, measures are taken to increase the melt viscosity of the polymer. However, in this case, each single yarn of the filament yarn spun from the spinneret is easily solidified in the vicinity of the spinneret. In addition, for example, some thermoplastic polymers have a higher glass transition temperature compared to commonly used polyesters and polyamides, and in filament yarns composed of such special polymers, Each single yarn of the filament yarn is easily solidified very close to the spinneret.

  Furthermore, when combining a plurality of functions as described above, for example, combining single yarn fineness / multifilament and single yarn irregular cross-section, or combining single yarn fineness / multifilament and polymer modification, etc. In some cases, these problems are even greater.

As mentioned above, as means for improving productivity, means such as high speed and multiple yarns can be mentioned. For example, in the field of melt spinning, the function of the filament yarn that can be produced when speed is increased. It is known that the width of the sex variation tends to be narrow. Specifically, it is known that the filament yarn obtained using UDY, POY, or DSD tends to have a wider range of functional variations than the OSY filament yarn. In addition, in recent years, in the field of melt spinning, there has been an increasing need to reduce the fineness of the filament yarn itself as a filament yarn for high-density fabrics, etc., and the production of filament yarn from a single spinneret has been maintained. On the other hand, it is considered that the importance of making multiple yarns capable of simultaneously producing a plurality of special filament yarns will increase further in the future.
In this way, when producing the above-mentioned special filament yarn with high productivity, particularly with multiple yarns, the temperature variation of the spinneret is suppressed, and the filament yarns spun from the spinneret are prevented. It is an extremely important factor to suppress fineness of the skin, and various proposals have been made.

  It should be noted that it is extremely difficult and unrealistic to correct the dimensions of the apparatus and the non-uniformity of the cooling airflow in the filament yarn manufacturing method based on mass production.

  For example, Patent Document 1 discloses a spinneret as shown in FIG. FIG. 16 is a front view of the spinneret of Patent Document 1. In the figure, 20 is a discharge hole, and 3 is a heat retaining collar. Hereinafter, in each drawing, when a member corresponding to the already-explained drawing exists, the description may be omitted by using the same reference numerals. In Patent Document 1, by providing the heat retaining collar 3 having an outer diameter larger than the diameter of the discharge hole 20 below the discharge hole 20, the cooling air from the cooling device does not directly hit the discharge hole 20, and the base surface It is described that the temperature distribution inside can be kept uniform. In addition, a new spinneret is proposed that significantly reduces the difference in fiber properties between the cooling air blowing side and the anti-cooling air blowing side by shortening the length of the heat retaining collar 3 as the distance from the cooling air blowing side of the cooling device increases. Has been. The heat retaining collar 3 and the discharge hole 20 may be configured independently, and it is recommended that the heat retaining collar 3 be made of a material other than a metal having poor heat transfer. When this method is used, even if the distance between the cooling device and the spinneret having the discharge holes 20 is shortened, the temperature distribution in the die surface can be kept uniform, and a yarn of sufficient quality can be obtained. Are listed.

  However, according to the knowledge of the present inventors, since there is a step between the discharge hole 20 and the heat retaining collar 3, spinning continues for a long time, and deposits such as monomers and oligomers are found around the discharge hole 20. When it accumulates, it becomes difficult to clean the base to remove it, and the yarn is bent, picked, and broken frequently. In the worst case, it is impossible to produce without changing the spinneret. May get worse. In addition, according to the knowledge of the present inventors, since the base surface has a shape like a concave portion because it is provided with the heat retaining collar 3, air current turbulence, yarn swaying occurs, There are cases in which physical properties such as strength and elongation deteriorate.

  Also, Patent Document 2 discloses a melt spinning method as shown in FIGS. FIG. 17 is a schematic view of the spinneret of Patent Document 2, and FIG. 18 is a partially enlarged view of FIG. In the figure, 1 is a spinneret, 4 is an introduction part, and 5 is an orifice part. The spinneret 1 of Patent Document 2 is composed of a plurality of introduction parts 4 and an orifice part 5 connected thereto, and the temperature distribution on the face of the base is accepted, and the length of the orifice part 5 depends on the position on the face of the base. A method is described in which the resistance at the time of passing through the discharge holes is made constant by adjusting the pressure and the discharge amount from each discharge hole can be made uniform.

  However, according to the knowledge of the present inventors, since the airflow directly under the base changes sequentially depending on the spinning conditions, it is necessary to prepare a spinneret corresponding to each change of the conditions. Therefore, there is a problem that the equipment cost becomes high. Further, according to the knowledge of the present inventors, if the temperature difference in the die surface becomes large, it may be difficult to sufficiently cope with the adjustment of the length of the orifice portion 5. In addition to the limit pressure of the polymer type, product type, and spinning machine, the length of the orifice portion 5 and the hole diameter must be determined in consideration of the die surface temperature distribution, and the design becomes extremely complicated. In addition, in order to design in consideration of the temperature distribution of the die surface, it is necessary to make a spinneret prototype and repeat the spinning evaluation several times. There is an oversized problem.

  A spinneret as shown in FIGS. 19 and 20 is disclosed in Patent Document 3. FIG. 19 is a plan view of the spinneret of Patent Document 3, and FIG. 20 is a partial longitudinal sectional view of FIG. In the figure, 6 is a pressing plate, 7 is a heating wire, 8 is a heating wire embedding groove, 9 is a temperature controller, 10 is a temperature sensor, 11 is a discharge hole start end, and 21 is an introduction hole. The spinneret of Patent Document 3 includes a presser plate 6, a heating wire 7, a temperature controller 9, a temperature sensor 10, a discharge hole 20, and an introduction hole 21, and a plurality of equal intervals corresponding to the discharge hole 20. The heating wire 7 formed in a linear or curved shape having a space is embedded in the vicinity of the discharge hole start end portion 11, and the heating wire 7 is heated by the temperature controller 9, thereby making the base surface temperature uniform. It is stated that it can be done.

  However, according to the knowledge of the present inventors, the heat radiation of the base surface differs depending on the position of the base surface. Therefore, the temperature of the base surface can be reduced only by arranging the heating wires 7 at equal intervals with respect to the discharge holes 20. The uneven state may not be improved. Further, adjusting the heat generation amount of the heating wire 7 using the temperature controller 9 in accordance with the heat radiation amount distribution on the base surface has a problem that the device configuration becomes too complicated. In addition, it is necessary to install the heating wire 7 and the temperature controller 9 in a high temperature part of about 300 ° C., and it is necessary to design in consideration of heat, and the maintenance frequency is excessive or workability is deteriorated. And there is a problem that the maintainability deteriorates. In addition, since the heating wire 7 is arranged between the discharge holes, the pitch between the discharge holes is restricted, and it becomes difficult to arrange the discharge holes 20 at a high density, which results in a problem that productivity is deteriorated. Moreover, since it is the structure which requires the heating wire 7 and the temperature controller 9 in addition to the spinneret, there is a problem that the equipment cost becomes high.

  Further, as a structure similar to that of Patent Document 3, a spinneret as shown in FIGS. 21 and 22 is disclosed in Patent Document 4. FIG. 21 is a front view of the spinneret of Patent Document 4, and FIG. 22 is a cross-sectional view taken along the line II in FIG. In the figure, 2 is a spinning hole, 12 is a laminated member, 13 is a heater member, and 14 is a lead wire. The spinneret of Patent Document 4 is composed of a laminated member 12 having a spinning hole 2, a heater member 13, and a lead wire 14, and the laminated member 12 is a ceramic (having a larger heat capacity than a metal and having a lower thermal conductivity). (For example, alumina is described in Patent Document 4), the gradient of the temperature distribution at the outer peripheral portion and the central portion of the spinneret becomes small, and even if the heater member 13 is heated, the laminated member 12 It is described that the temperature does not change rapidly, and as a result, the entire spinneret can always be kept at a uniform temperature.

  However, according to the knowledge of the present inventors, since the heater member 13 is installed, the maintainability is poor as in Patent Document 3, and the heater member 13 is disposed between the spinning holes 2. For this reason, the pitch between the spinning holes is restricted, it is difficult to arrange the spinning holes 2 densely, the productivity is deteriorated, and in addition, the heater member 13 is embedded, so that the installation cost may be high. is there. Further, according to the knowledge of the present inventors, in the structure in which the spinning hole 2 is a ceramic laminated member 12, the dimensional accuracy of the spinning hole 2 and the hole length is inferior to that of stainless steel. As a result, there is a case where the discharge amount of the polymer is not uniform between the discharge holes, that is, the uneven discharge of the polymer discharge occurs. Further, because of the laminated structure of ceramics, a step is likely to occur in the spinning hole 2, and the abnormal position of the polymer is likely to occur due to the step position as a base point. In addition, general-purpose polymers such as polyester and polyamide have not been a problem, but polymer discharge flow spots may become more conspicuous for polymers having a high temperature dependence of melt viscosity.

  On the other hand, another important function of the spinneret is a function of stably discharging the polymer. However, in actual melt spinning, the spinneret is exposed to a high temperature of about 300 ° C. for a long time, and the additives, monomers, and oligomers contained in the polymer adhere to and deposit around the discharge holes, and the spinneret surface becomes dirty. Thus, it is known that the discharge of the polymer is hindered, the discharge polymer is bent and the yarn is broken, and the yarn-making property is unstable.

  Therefore, in order to reduce the contamination of the base surface, a spinneret as shown in FIG. FIG. 23 is a partial vertical cross-sectional view of the spinneret of Patent Document 5. In the figure, 15 is an upper cap, 16 is a lower cap, 17 is an introduction / guide hole, and 18 is a ceramic nozzle tip 18.

  The spinneret of Patent Document 5 is composed of a lower base 16 in which a ceramic nozzle tip 18 having a discharge hole 20 is embedded, and an upper base 15 having an introduction / guide hole 17, and the lower base 16 is made of ceramics. It is also proposed to make it. According to Patent Document 5, ceramics excellent in wear resistance, heat resistance, and releasability are disposed in the discharge holes 20 while maintaining the hole arrangement density of the discharge holes 20 in the metal base. It is described that the production cycle of the spinneret can be greatly extended by suppressing the generation of such deposits.

  However, according to the knowledge of the present inventors, the occurrence of contamination on the die surface is not completely eliminated even with a ceramic die, and the occurrence is unavoidable if spinning is continued for a long time. Therefore, when dirt is generated around the discharge hole 20, it is necessary to clean the die by spraying a release agent such as silicon onto the die surface and scraping with a cleaning jig such as a spatula. In general, ceramics are known to be inferior in toughness, although they are superior in hardness to stainless steel. For this reason, the discharge hole 20 may be cracked, chipped, or the like due to a slight impact caused by a spatula or the like during base cleaning, and the life of the spinneret itself may be shortened. Further, when silicon is sprayed on the base surface during base cleaning, the base surface temperature rapidly decreases. For this reason, internal stress due to a rapid temperature difference is generated inside the die, and cracks and chipping may occur. Moreover, since the processing accuracy of the hole diameter and the hole length of the discharge hole 20 is inferior to that of a metal member such as stainless steel, the discharge amount at each discharge hole may be uneven due to dimensional accuracy variation.

  Further, according to the knowledge of the present inventors, in the above-mentioned Patent Document 4, since a ceramic sintered body is employed on the base surface, cracking and chipping are generated in the base cleaning as in Patent Document 5. There is a case.

  In addition, as a surface modification technique that makes it difficult for dirt on the die surface to adhere to the die surface, Patent Document 6 proposes coating a metal die with ceramics. Cracking and chipping may occur.

  As described above, suppressing temperature unevenness in the spinneret and suppressing fineness irregularities between the filament yarns spun from the spinneret are extremely important factors in improving the productivity of filament yarn production. However, as described above, according to the knowledge of the present inventors, various problems remain, which hinders the improvement of the productivity of filament yarn production. Therefore, solving the problems related to the suppression of fineness spots has an important industrial significance.

JP 2001-303355 A Japanese Unexamined Patent Publication No. 2-333325 Japanese Patent Laid-Open No. 60-139721 JP 58-136833 A JP 2000-303249 A Japanese Patent Laid-Open No. 2-74620

  The object of the present invention is to cope with various polymer types and varieties, the production cost of the spinneret is low, the maintainability and durability are high, and even if foreign matter adheres to the discharge hole, it can be easily removed, and the spinning Spinneret and filament yarn with excellent stability, small unevenness between single yarns and between yarns, and remarkable effect to obtain yarns with good quality such as thickness unevenness, strength and elongation It is in providing the manufacturing method of.

In order to achieve the above object, according to the present invention, there is provided a spinneret provided with spinning holes for spinning a polymer as a filament yarn, which satisfies the following requirements (1) to (4): A base is provided.
(1) The spinning hole includes at least an introduction hole, and a discharge hole that is arranged downstream of the introduction hole in the spinning path direction of the polymer and discharges the polymer from the lower surface of the spinneret. To be done.
(2) The spinneret includes at least an upper plate in which the introduction hole is disposed and a lower plate in which the discharge hole is disposed.
(3) The cross-sectional area of the introduction hole in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole in the direction perpendicular to the polymer spinning path direction.
(4) The thermal conductivity of the upper plate is smaller than the thermal conductivity of the lower plate.

According to another aspect of the present invention, there is provided a spinneret provided with spinning holes for spinning a polymer as a filament yarn, which satisfies the following requirements (5) to (8): Is provided.
(5) The spinning hole includes at least an introduction hole, and a discharge hole that is arranged downstream of the introduction hole in the spinning path direction of the polymer and discharges the polymer from the lower surface of the spinneret. To be done.
(6) The spinneret includes at least an outer peripheral layer that forms the introduction hole and a lower plate on which the discharge hole is disposed.
(7) The cross-sectional area of the introduction hole in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole in the direction perpendicular to the polymer spinning path direction.
(8) The thermal conductivity of the outer peripheral layer is smaller than the thermal conductivity of the lower plate.

According to another aspect of the present invention, there is provided a spinneret provided with spinning holes for spinning a polymer as a filament yarn, which satisfies the following requirements (9) to (12): Is provided.
(9) The spinning hole is at least an introduction hole, an intermediate introduction hole disposed downstream of the introduction hole in the polymer spinning path direction, and the polymer spinning path from the intermediate introduction hole. And a discharge hole which is disposed on the downstream side in the direction and discharges the polymer from the lower surface of the spinneret.
(10) The spinneret includes at least an upper plate provided with the introduction hole, an intermediate plate provided with the intermediate introduction hole, and a lower plate provided with the discharge hole. thing.
(11) The cross-sectional area of the introduction hole in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole in the direction perpendicular to the polymer spinning path direction.
(12) The thermal conductivity of the intermediate plate is smaller than the thermal conductivity of the lower plate.

  According to a preferred embodiment of the present invention, an intermediate plate having an intermediate introduction hole for connecting the introduction hole and the discharge hole is provided, and the thermal conductivity of the intermediate plate is higher than the thermal conductivity of the lower plate. A small spinneret is provided.

  Moreover, according to the preferable form of this invention, the spinneret which provided the space | gap in the said intermediate plate as a means to make small the heat conductivity of the said intermediate plate is provided.

  According to a preferred embodiment of the present invention, there is provided a spinneret in which a metering hole is provided in a part of the introduction hole in the direction of the polymer spinning path.

  Moreover, according to the preferable form of this invention, the manufacturing method of the filament yarn which manufactures a multifilament yarn using one of said spinneret is provided.

  In the present invention, the “polymer spinning path direction” refers to the principal axis direction of the flow path through which the polymer passes.

  According to the spinneret and multifilament yarn manufacturing method of the present invention, it is possible to cope with various polymer types and varieties, the spinneret is highly maintainable and durable, and can be easily removed even if foreign matter adheres to the discharge hole. At the same time, it is possible to obtain a yarn having excellent spinning stability, small fineness unevenness between single yarns and yarns, and good quality such as yarn thickness unevenness and strength / elongation.

It is a top view of a spinneret used for a 1st embodiment of the present invention. It is a schematic sectional drawing of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the spinneret used for the 2nd Embodiment of this invention. It is a schematic sectional drawing of the spinneret used for the 3rd Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 2nd Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the other preferable form of the spinneret used for the 1st Embodiment of this invention. It is a schematic sectional drawing of the spinneret used for the 1st Embodiment of this invention, and a cooling device periphery. This shows the relationship between the shear rate and the melt viscosity of two types of polymers with different temperatures employed in the present invention. It is a front view of a spinneret of a conventional example. It is a schematic sectional drawing of the spinneret of a prior art example. It is an enlarged view of FIG. It is a front view of a spinneret of a conventional example. FIG. 20 is a partial vertical sectional view of FIG. 19. It is a front view of a spinneret of a conventional example. It is II sectional drawing of FIG. It is a fragmentary longitudinal cross-sectional view of a conventional spinneret.

  Hereinafter, the best embodiment of the method for producing a spinneret and filament yarn of the present invention will be described in detail with reference to the drawings. 1 is a plan view of a spinneret used in the first important embodiment of the present invention, FIG. 2 is a schematic cross-sectional view of FIG. 1, and FIG. 5, FIG. 7, FIG. 8, FIG. 10, FIG. 11, FIG. 12, and FIG. 13 are schematic cross-sectional views of other preferred forms used in the first embodiment of the present invention, and FIG. 14 is used in the first embodiment of the present invention. It is a schematic sectional drawing of a spinneret and a cooling device periphery. As shown in FIG. 14, the spinneret 1 used in the first embodiment of the present invention is mounted on a spin pack 26 together with a perforated plate 19, a packing 29, and the like, fixed in a spin block 27, and the spinneret. 1, a cooling device 28 is configured. Therefore, the polymer guided to the spin pack 26 passes through the perforated plate 19 and the spinneret 1 and is discharged from the lower face 32 of the discharge hole 20 and then cooled by the airflow blown out by the cooling device 28, and the oil agent After being applied, it is wound up as a multifilament yarn. In FIG. 14, a configuration is adopted in which steam is applied by the steam applying device 35 and the base lower surface 32 is sealed.

  As shown in FIG. 2, the spinneret 1 used in the first embodiment of the present invention includes an introduction hole 21 composed of a columnar channel such as a cylinder, an upper plate 22 provided with the introduction hole 21, From the downstream side of the introduction hole 21 in the polymer spinning path direction, from the discharge hole 20 formed of a columnar flow path such as a cylinder drilled facing the lower surface 32 of the base, and the lower plate 23 provided with the discharge hole 20 And the cross-sectional area of the introduction hole 21 in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole 20 in the direction perpendicular to the polymer spinning path direction. The thermal conductivity is smaller than that of the member of the lower plate 23. In that case, the upper plate 22 and the lower plate 23 are positioned with positioning pins so that the center positions (cores) of the introduction hole 21 and the discharge hole 20 are aligned, and after being overlapped, fixed with screws, bolts, or the like. Alternatively, metal bonding may be performed by thermocompression bonding. Further, it is preferable that the upper plate 22 is configured with a throttle-shaped flow path such as a truncated cone for communicating the introduction hole 21 and the discharge hole 20.

  First, by adopting the configuration of the first embodiment described above, both the discharge flow rate irregularity of the polymer discharged from the base lower surface 32 of the spinneret 1 and the problems associated with cleaning the base surface are simultaneously solved. Explain the principle that can be done. One of the causes for the occurrence of unevenness in the discharge flow rate of the polymer is one caused by deterioration of dimensional accuracy such as the diameter and length of the discharge hole, and the other is the melt viscosity of the polymer caused by temperature unevenness generated on the die surface. The thing resulting from a spot is mentioned. Note that the former has been improved in machining accuracy in recent years, the dimensional accuracy of the discharge holes has been improved, and the influence has been reduced. Accordingly, it is important to suppress polymer discharge flow rate unevenness due to temperature unevenness on the base surface, and to suppress fineness unevenness between each single yarn and each yarn resulting therefrom.

  FIG. 15 shows the relationship between the shear rate and the melt viscosity at different temperatures of the polymer used in this embodiment. This relationship also applies to general purpose polymers such as nylon 6, nylon 66, and polyester. Generally, the melt viscosity of a polymer strongly depends on the temperature and the shear rate. The higher the temperature, the lower the melt viscosity, and the lower the temperature, the higher the melt viscosity. The lower the shear rate, the higher the viscosity, and the higher the shear rate, the lower the melt viscosity. Therefore, when the melt viscosity difference ΔηL at the temperature difference ΔT in the low shear region is compared with the melt viscosity difference ΔηH at the temperature difference ΔT in the high shear region, ΔηL> ΔηH. That is, the melt viscosity difference due to the temperature difference is large in the low shear region, but the melt viscosity difference due to the temperature difference tends to be small in the high shear region. The present invention has been devised by paying attention to this feature.

  The inventors of the present invention have found a technique that suppresses unevenness in the discharge flow rate of the polymer while enhancing the cleanability of the spinneret, which is not considered in the prior art. That is, as shown in FIG. 2, the spinneret 1 is divided into a portion having a low shear rate and a portion having a high shear rate (that is, a portion having a large cross-sectional area in a direction perpendicular to the direction of the polymer spinning path and a portion having a small cross section). The upper plate 22 and the lower plate 23 are divided into two parts, the upper plate so that the temperature variation is difficult to propagate to the portion of the introduction hole 21 where the shear rate is small and the change in the melt viscosity difference of the polymer is likely to increase due to the temperature difference. The thermal conductivity of 22 was reduced. This makes it difficult for temperature spots to propagate to the introduction hole 21, so that the polymer discharge flow spot caused by the temperature spots on the base lower surface 32 can be greatly suppressed.

  In addition, the first embodiment of the present invention can also solve the problem of cleaning the base lower surface 32 that tends to accompany the problem of temperature spots. That is, in order to solve the above temperature spots, it is preferable to employ a material having excellent heat insulation, for example, ceramics or the like for the spinneret 1, but such a material is often excellent in heat insulation, Since the toughness is inferior, many of them are easily cracked or chipped. For this reason, as described in the background art, there is a problem that the bottom surface 32 of the base cannot be cleaned and cracks and chips are generated in the vicinity of the discharge holes 20.

  On the other hand, in the first embodiment of the present invention, the upper plate 22 and the lower plate 23 are divided. Particularly, the shear rate of the polymer is large, and the melt viscosity of the polymer is influenced by temperature spots such as the die surface. The lower plate 23 is less likely to have a large difference in thermal conductivity, high strength, and excellent corrosion resistance and toughness, for example, a generally used steel material such as stainless steel. No cracking or chipping when cleaning. In addition, since the upper plate 22 where the difference in melt viscosity of the polymer is likely to increase due to temperature spots on the die surface or the like, a material having a low thermal conductivity and excellent heat insulation, such as ceramics, can be used. Flow spots can be greatly suppressed. Therefore, the present invention can solve both of the discharge flow rate unevenness of the polymer and the problems associated with the cleaning of the base surface at the same time.

  Furthermore, since the bottom surface 32 of the base can be made constant, that is, smooth, it is possible to prevent the occurrence of air current turbulence and yarn swaying directly below the spinneret 1, improve spinning stability, increase the thickness variation, It is possible to reduce physical properties such as elongation.

  In addition to the role of discharging the polymer from the base lower surface 32, the discharge hole 20 plays a role of weighing the polymer, and the dimensional accuracy of the hole diameter and the hole length directly affects the polymer discharge amount unevenness. Strict dimensional accuracy is required. In this embodiment, in order to pierce the discharge hole 20 that requires this accuracy, there is an advantage that stainless steel can be used that is inexpensive and has good machinability, and excellent in processing accuracy by about 1 to 2 digits compared to ceramics. Have.

  Further, another embodiment having the same effect as the first embodiment of the present invention but also having a different effect will be described with reference to FIGS. 9, 10, and 11. As shown in FIG. 9, the lower plate 23 may be configured with a throttle-shaped flow path such as a truncated cone that allows the discharge hole 20 and the introduction hole 21 to communicate with each other. Further, as shown in FIG. 10, the upper plate 22 is connected to a drawing-shaped channel such as a truncated cone for communicating the introduction hole 21 and the discharge hole 20, and a direction perpendicular to the polymer spinning path direction of the discharge hole 20. A flow path that connects columnar flow paths such as cylinders having a cross-sectional area equal to the cross-sectional area may be configured, or a narrow flow path such as a truncated cone and a columnar flow path such as a cylinder are connected multiple times. A flow path may be configured. Further, as shown in FIG. 11, the lower plate 23 has a constriction-shaped flow path such as a truncated cone for communicating the discharge hole 20 and the introduction hole 21, and a direction perpendicular to the polymer spinning path direction of the introduction hole 21. A flow path that connects columnar flow paths such as cylinders having a cross-sectional area equal to the cross-sectional area may be configured, or a narrow flow path such as a truncated cone and a columnar flow path such as a cylinder are connected multiple times. A flow path may be configured. In that case, the abnormal confinement of the polymer can be suppressed as much as possible by configuring the truncated conical throttle-shaped flow path. Here, if the expansion angle of the throttle-shaped flow path is increased, a dead space is generated and the polymer is liable to stay. Conversely, if the expansion angle is decreased, abnormal retention of the polymer is suppressed, but the flow of the throttle-shaped flow path is suppressed. Since the path length becomes long and, as a result, the entire spinneret 1 becomes large, it is preferable to adjust the spread angle appropriately in the range of 30 to 120 degrees. In the embodiment of FIG. 11, the introduction surface 21 having a relatively large hole diameter is formed on the mating surface of the upper plate 22 and the lower plate 23, so that the upper plate 22 and the lower plate 23 can be easily aligned and misalignment occurs. It becomes difficult to occur.

  Further, another embodiment having the same effect as that of the first embodiment of the present invention but also having a different effect will be described with reference to FIG. As shown in FIG. 8, a configuration may be employed in which a measuring hole 31 having a diameter smaller than that of the introduction hole 21 is disposed in a part of the introduction hole 21 in the polymer spinning path direction. In that case, in addition to the discharge hole 20 for measuring the polymer, the metering hole 31 is provided in a part of the introduction hole 21, thereby improving the meterability of the polymer discharged from the discharge hole 20. Discharge flow spots can be suppressed.

  Further, another embodiment having the same effect as that of the first embodiment of the present invention but also having a different effect will be described with reference to FIG. As shown in FIG. 13, an introduction hole 21 having the same thermal conductivity as that of the lower plate 23 is continuously arranged on the upstream side of the polymer spinning path direction of the upper plate 22, and the polymer of the introduction hole 21 is spun. A configuration may be adopted in which a measuring hole 31 having a hole diameter smaller than that of the introduction hole 21 is provided in a part of the exit path direction. In that case, in addition to the discharge hole 20 that is measuring the polymer, the measurement hole 31 is disposed, so that the measurement property of the polymer discharged from the discharge hole 20 is improved. By moving away from the base lower surface 32, the influence of temperature spots on the base lower surface 32 can be reduced, and the discharge flow rate spots of the polymer can be suppressed.

  Further, another embodiment having the same effect as that of the first embodiment of the present invention but having a different effect will be described with reference to FIG. As shown in FIG. 12, a configuration in which a plurality of discharge holes 20 are provided for one introduction hole 21 may be used, and the number of discharge holes 20 is not limited. In that case, the cross-sectional area in the direction perpendicular to the polymer spinning path direction of the introduction hole 21 is the sum of the cross-sectional areas in the direction perpendicular to the polymer spinning path direction of all the discharge holes 20 connected to the introduction hole 21. Configured to be larger. By disposing a plurality of discharge holes 20 with respect to one introduction hole 21, the discharge holes 20 can be disposed at a high density on the base lower surface 32.

  Another embodiment having the same effect as the first embodiment of the present invention but also having a different effect will be described with reference to FIG. As shown in FIG. 5, between the upper plate 22 and the lower plate 23, an intermediate introduction hole 25 that connects the introduction hole 21 and the discharge hole 20 and an intermediate plate 24 in which the intermediate introduction hole 25 is disposed are configured. Further, the thermal conductivity of the member of the intermediate plate 24 may be smaller than the thermal conductivity of the member of the lower plate 23. In this case, it is possible to suppress the temperature spots on the lower plate 23 from being transmitted to the upper plate 22, and as a result, the upper plate 22 is soaked and the discharge flow rate spots of the polymer can be suppressed. Further, when materials having different thermal conductivities are used for the upper plate 22 and the lower plate 23, the linear expansion coefficients of the respective members are different, so that the positions of the introduction hole 21 and the discharge hole 20 are likely to be displaced at high temperatures. By disposing the intermediate plate 24 having an intermediate linear expansion coefficient between the upper plate 22 and the lower plate 23, the positional deviation can be reduced. Further, the intermediate plate 24 is a lower surface of the upper plate 22 (a surface opposite to the upper surface 33 of the base, a surface on the side of the intermediate plate 24) or an upper surface of the lower plate 23 (a surface opposite to the lower surface of the base 32, a surface on the side of the intermediate plate 24). ), Or the lower surface of the upper plate 22 and the upper surface of the lower plate 23 may be coated with a liquid having low thermal conductivity, or may be vapor-phase coated using physical vapor deposition or chemical vapor deposition. Good. The intermediate introduction hole 25 is preferably a constricted channel such as a truncated cone connecting the introduction hole 21 and the discharge hole 20 in order to suppress abnormal retention of the polymer. A columnar channel such as a cylinder having the same cross-sectional area in the direction perpendicular to the spinning path direction may be used, or a columnar channel such as a cylinder having the same cross-sectional area in the direction perpendicular to the direction of spinning of the discharge holes 20 and the polymer may be used.

  An embodiment having the same effect as the first embodiment of the present invention but also having a different effect will be described with reference to FIG. As shown in FIG. 7, in addition to the intermediate introduction hole 25 connecting the introduction hole 21 and the discharge hole 20 and the intermediate plate 24 provided with the intermediate introduction hole 25, the upper plate is used as a means for reducing the thermal conductivity. Alternatively, the air layer 30 may be disposed between the lower plate 22 and the lower plate 23. By providing the air layer 30, it is possible to suppress the temperature spots on the base lower surface 32 from transferring heat from the lower plate 23 to the upper plate 22, so that the upper plate 23 is temperature-equalized and the discharge flow rate spots of the polymer can be suppressed. In addition, the air layer 30 may be filled with normal-pressure air, but the heat insulating property can be further enhanced by applying a vacuum. Furthermore, heat insulation can be strengthened by filling argon, carbon monoxide, carbon dioxide, and ammonia as a gas having low thermal conductivity.

  Next, as shown in FIG. 3, the second embodiment of the present invention will be described as a different embodiment having the same effects as those of the first embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of the spinneret 1 used in the second embodiment of the present invention, an introduction hole 21 formed of a columnar flow path such as a cylinder, an outer peripheral layer 34 in which the introduction hole 21 is formed, From the downstream side of the introduction hole 21 in the polymer spinning path direction, from the discharge hole 20 formed of a columnar flow path such as a cylinder drilled facing the lower surface 32 of the base, and the lower plate 23 provided with the discharge hole 20 And the cross-sectional area in the direction perpendicular to the polymer spinning path direction of the introduction hole 21 is larger than the cross-sectional area in the direction perpendicular to the polymer spinning path direction of the discharge hole 20, and The thermal conductivity is smaller than the thermal conductivity of the member of the lower plate 23. In that case, only the outer peripheral layer 34 of the spinneret 1 can be made of a material having low thermal conductivity, an efficient heat insulation performance can be obtained, and temperature spots can be suppressed. In addition, since the outer peripheral layer 34 can be fitted as a piece part of the spinneret 1, it can be easily attached and removed, and the outer peripheral layer 34 can be replaced depending on the polymer type and product type, so that the equipment cost is low. Can be. Further, as another method for reducing the thermal conductivity of the outer peripheral layer 34, a liquid having a low thermal conductivity may be coated on the side surface of the flow path of the introduction hole 21, and physical vapor deposition or chemical vapor deposition may be performed. May be used for vapor phase coating.

  Further, another embodiment having the same effect as the second embodiment of the present invention but also having a different effect will be described with reference to FIG. Similar to the first embodiment described above, the intermediate introduction hole 25 and the intermediate plate 24 are configured to suppress conduction of temperature spots on the lower plate 23 to the outer peripheral layer 34. Can be soaked and polymer discharge flow spots can be suppressed.

  Next, as shown in FIG. 4, the third embodiment of the present invention will be described as a different embodiment having the same effects as those of the first and second embodiments of the present invention. FIG. 4 is a schematic cross-sectional view of the spinneret 1 used in the third embodiment of the present invention. The introduction hole 21 is a columnar flow path such as a cylinder, and the upper plate 22 is provided with the introduction hole 21. The intermediate introduction hole 25 disposed downstream of the introduction hole 21 in the polymer spinning path direction, the intermediate plate 24 provided with the intermediate introduction hole 25, and the polymer spinning path direction of the intermediate introduction hole 25 , A discharge hole 20 composed of a columnar flow path such as a cylinder perforated facing the base lower surface 32 and a lower plate 23 provided with the discharge holes 20, and the polymer of the introduction hole 21 is spun. The cross-sectional area in the direction perpendicular to the discharge path direction is larger than the cross-sectional area in the direction perpendicular to the polymer spinning path direction of the discharge hole 20, and the thermal conductivity of the member of the intermediate plate 24 is set as the member of the lower plate 23. It has a feature that is smaller than the thermal conductivity. Similar to the first embodiment described above, the intermediate introduction hole 25 and the intermediate plate 24 are configured to suppress the temperature spots on the lower plate 23 from being transmitted to the upper plate 22, and the upper plate 22. Is soaked and polymer discharge flow spots can be suppressed. Further, the spinneret 1 is divided into two parts, that is, an upper plate 22 and a lower plate 23, and an intermediate plate 24 is sandwiched or coated between them. can do.

  Next, the first embodiment of the present invention shown in FIG. 2, the second embodiment of the present invention shown in FIG. 3, and the spinneret 1 of the third embodiment of the present invention shown in FIG. Each member and the shape of each member common to the above will be described in detail.

  The spinneret 1 of the first embodiment, the second embodiment, and the third embodiment of the present invention is not limited to a circular shape, and may be a quadrangle or a polygon. Further, the arrangement of the discharge holes 20 in the spinneret 1 may be appropriately determined according to the number of multifilament yarns, the number of yarns, and the cooling device 28. In the annular cooling device that blows cooling air from the outer periphery to the inner periphery as the cooling device 28, the discharge holes 20 are preferably arranged in a ring or in a plurality of rows, and the one-way cooling that blows the cooling air from one direction. In the apparatus, the discharge holes 20 are preferably arranged in a staggered manner. In that case, the airflow blown from the cooling device 28 can easily pass between the yarns and the yarns, thereby suppressing yarn unevenness, reducing yarn physical property unevenness, and further reducing yarn breakage.

  The discharge hole 20 and the introduction hole 21 of the first embodiment, the second embodiment, and the third embodiment of the present invention are not limited to a circular cross section in a direction perpendicular to the polymer spinning path direction. Alternatively, an irregular cross-sectional shape or a hollow cross-sectional shape may be used.

  In addition, the material of the upper plate 22 and the outer peripheral layer 34 of the first and second embodiments of the present invention is preferably zirconium oxide made of ceramics (thermal conductivity 3 W / m · K) with low thermal conductivity. However, it is sufficient that the thermal conductivity is lower than that of the lower plate 23. For example, as the material of the upper plate 22 and the outer peripheral layer 34, Inconel 600, Inconel having a thermal conductivity in the range of 3 to 15 W / m · K. X750, Incoloy 800, Hastelloy X, Stellite 6B, Nimonic 80A, Nichrome, super steel alloy (chemical composition formula: 34WC-60Tic-6Co), 6Al-4V alloy, and the like may be used.

  The material of the upper plate 22 of the third embodiment of the present invention is most preferably SUS630 (heat treatment H1075) which has high strength and excellent corrosion resistance, but may be SUS420J2 of other stainless steel. SUS304 or carbon steel. (Stainless steel thermal conductivity range: 15 to 30 W / m · K) Further, as described above, it may be ceramic zirconium oxide having a small thermal conductivity, and the lower plate 23 only needs to have a low thermal conductivity. For example, the material of the upper plate 22 is Inconel 600, Inconel X750, Incoloy 800, Hastelloy X, Stellite 6B, Nimonic 80A, Nichrome, super steel alloy (chemical composition: 34WC-60Tic-6Co), 6Al-4V alloy, etc. May be.

  In addition, as described above, the material of the lower plate 23 of the first embodiment, the second embodiment, and the third embodiment of the present invention is SUS630 (heat treatment H1075) having high strength and excellent corrosion resistance and toughness. Is most suitable, but may be SUS420J2 of other stainless steel, SUS304, carbon steel or the like.

  Further, as described above, the material of the intermediate plate 24 of the spinneret 1 used in the present invention is preferably ceramic zirconium oxide having a low thermal conductivity, but if the thermal conductivity is lower than that of the lower plate 23. Well, for example, as the material of the intermediate plate 24, Inconel 600, Inconel X750, Incoloy 800, Hastelloy X, Stellite 6B, Nimonic 80A, Nichrome, super steel alloy (chemical composition formula: 34WC-60Tic-6Co), 6Al-4V alloy Etc.

  The present invention is an extremely versatile invention and is suitable for all multifilament yarns obtained by a spinneret and a method for producing filament yarns. Therefore, it is not particularly limited by the polymer constituting the multifilament yarn. For example, polyesters, polyamides, polyphenylene sulfides, polyolefins, polyethylenes, polypropylenes, etc. can be cited as examples of polymers constituting the multifilament yarn suitable for the present invention.

  Furthermore, in the above-mentioned polymers, matting agents such as titanium dioxide, silicon oxide, kaolin, anti-coloring agents, stabilizers, antioxidants, deodorizers, flame retardants, yarn friction, as long as yarn production stability is not impaired. Various functional particles such as a reducing agent, a color pigment, and a surface modifier, additives such as organic compounds may be contained, and copolymerization may be included.

  Moreover, the polymer used for this invention may be comprised by a single component, or may be comprised by multiple components, and in the case of a multiple component, structures, such as a core sheath and a side-by-side, are mentioned, for example. In addition, the cross-sectional shape of the multifilament yarn may be an irregular shape such as a circle, a triangle, a flat shape, or a hollow shape.

  The present invention is an extremely versatile invention and is suitable for all multifilament yarns obtained by a spinneret and a method for producing a multifilament yarn. Therefore, it is not particularly limited by the single yarn fineness of the multifilament yarn. The smaller the single yarn fineness, the clearer the difference from the prior art.

  Moreover, it is not particularly limited by the number of single yarns of the multifilament yarn, and as the number of single yarns of the multifilament yarn is larger, the difference from the conventional technique becomes clearer. Furthermore, it is not particularly limited by the number of yarns of the multifilament yarn, and may be one yarn or a multi yarn of two or more yarns. When manufacturing multifilament multifilament yarn, a perforated portion in which the discharge hole 20 is perforated on the base lower surface 32 and a non-perforated portion in which the discharge hole 20 is not perforated are provided. Then, since the passing amount of the air flow blown from the cooling device 28 is different, the temperature difference of the base surface is likely to occur. Therefore, the difference from the conventional one becomes clearer by using the spinneret 1 of the present invention.

  In the case of producing a multifilament yarn using the spinneret 1 of the present invention, the polymer is discharged from the spinneret 1, cooled by the cooling air blown from the cooling device 28, taken up, and then wound up. The film may be stretched or stretched, and may be wound without being stretched.

Each characteristic value used in the examples was determined by the following measurement method.
(1) Fineness variation value CV (%), fineness unevenness:
The fineness of the yarn of the multifilament yarn is measured according to JIS L 1013-1999 8.3.1 fineness fineness fineness A method, and with respect to the fineness variation rate CV (%) obtained from the following formula: “Less than 1.0” was evaluated as 、, “1.0 or more and less than 1.5” as ◯, “1.5 or more and less than 2.0” as Δ, and “2.0 or more” as x. .

Fineness variation rate CV (%) = (standard deviation of yarn fineness) / (arithmetic average of yarn fineness) × 100
(2) Thread breakage:
When spinning, sample a ton of 2 tons, collect the number of yarn breaks during this time, measure "less than 1.5 times", "1.5 times or more and less than 3 times", "3 times or more and 5 times" “Less than” was evaluated as Δ, and “more than 5 times” was evaluated as ×.
(3) Intrinsic viscosity [η]
Measurement was performed at 25 ° C. using orthochlorophenol as a solvent.
(4) 98% sulfuric acid relative viscosity [ηr]
(A) A sample is weighed and dissolved in 98% by weight concentrated sulfuric acid so that the sample concentration (C) is 1 g / 100 ml.
(B) The drop rate (T1) at 25 ° C. of the solution of item (a) is measured with an Ostwald viscometer.
(C) Measure the drop rate (T2) at 25 ° C. of 98% by weight concentrated sulfuric acid not dissolving the sample.
(D) The 98% sulfuric acid relative viscosity (ηr) of the sample is calculated by the following formula. The measurement temperature is 25 ° C.

[Ηr] = (T1 / T2) + {1.891 × (1.000−C)}
[Example 1]
A polymer of nylon 6 (chip of 98% sulfuric acid relative viscosity [ηr] 2.8, melting temperature 260 ° C.) is melted and discharged from the spinneret 1 according to the first embodiment of the present invention. Was sprayed onto the lower surface 32 of the die, cooled by the cooling device 28, and then oiled, entangled, and hot drawn, and taken up at a speed of 4000 m / min with a winding roller to produce a multifilament yarn. At this time, as shown in FIG. 2, the spinneret 1 uses ceramic zirconium oxide as the material of the upper plate 22, SUS630 (heat treatment H1075) as the material of the lower plate 23, and the diameter φ1 of the introduction hole 21. The diameter of the discharge hole 20 was 0.17 mm, and the discharge holes 20 were arranged in an annular shape. As a result of producing 10 dtex, 19 filament yarns, and 6 yarns of polyamide fiber using the above spinneret 1, the fineness variation rate was 0.8%. As shown in Table 1, the best results were obtained for the yarn breakage during spinning, and the fineness unevenness of the obtained fibers obtained the best results.
[Example 2]
Example 2 will be described as an example using the spinneret 1 according to the second embodiment of the present invention, in which spinning is performed with a polymer equivalent to Example 1, the same fineness, and the number of yarns. As the spinneret 1, as shown in FIG. 3, ceramic zirconium oxide is used as the material of the outer peripheral layer 34 forming the introduction hole 21, SUS630 (heat treatment H1075) is used as the material of the lower plate 23, and the introduction hole 21. The hole diameter was 1.5 mm, the diameter of the discharge hole 20 was 0.17 mm, and the discharge holes 20 were arranged in an annular shape. As a result of producing a polyamide fiber using the spinneret 1 described above, the fineness variation rate was 1.2%. As shown in Table 1, the best results were obtained for yarn breakage during spinning, and good results were obtained for fineness unevenness of the obtained fibers.
[Example 3]
Example 3 will be described as an example using the spinneret 1 according to the third embodiment of the present invention, in which spinning is performed with a polymer equivalent to Example 1, the same fineness, and the number of yarns. As shown in FIG. 4, as the spinneret 1, SUS630 (heat treatment H1075) is used as the material of the upper plate 22, SUS630 (heat treatment H1075) is used as the material of the lower plate 23, and ceramic zirconium oxide is used as the material of the intermediate plate 24. Further, the diameter of the introduction hole 21 was 1.5 mm, the diameter of the discharge hole 20 was 0.17 mm, and the discharge holes 20 were arranged in an annular shape. As a result of producing a polyamide fiber using the spinneret 1 described above, the fineness variation rate was 1.4%. As shown in Table 1, the best results were obtained for yarn breakage during spinning, and good results were obtained for fineness unevenness of the obtained fibers.
[Example 4]
Spinning with the same polymer, equivalent fineness, and number of yarns as in Example 3, the material of the upper plate 22 of the spinneret 1 of the third embodiment of the present invention is changed to ceramic zirconium oxide, and the intermediate plate Example 4 will be described as an example in which an air layer 30 is provided at 24. In the spinneret 1, as shown in FIG. 7, ceramic zirconium oxide is used for the upper plate 22, SUS630 (heat treatment H1075) is used for the lower plate 23, and ceramic zirconium oxide is used for the intermediate plate 24. Further, the introduction hole 21 has a hole diameter φ1.5 mm and the discharge hole 20 has a hole diameter φ0.17 mm, and the discharge holes 20 are arranged in an annular shape. The air layer 30 was filled with air in a completely sealed space. As a result of producing a polyamide fiber using the spinneret 1 described above, the fineness variation rate was 0.8%. As shown in Table 1, the yarn breakage during spinning was good, and the fineness unevenness of the obtained fiber gave the best result.
[Example 5]
As an example in which spinning is performed with a polymer equivalent to Example 1, an equivalent fineness, and the number of yarns, and a measuring hole 31 is provided in a part of the introduction hole 21 of the spinneret 1 of the first embodiment of the present invention. Example 5 will be described. As a result of producing a polyamide fiber using the spinneret 1 having a hole diameter φ0.17 mm of the measuring hole 31, the fineness variation rate was 0.7%. As shown in Table 1, the best results were obtained for the yarn breakage during spinning, and the fineness unevenness of the obtained fibers obtained the best results.
[Comparative Example 1]
In the spinneret 1 used in Example 1, the material of the upper plate 22 was changed to SUS630 (heat treatment H1075), and other than that, using the same spinneret 1 as in Example 1, the same polymer, fineness, yarn As a result of producing the polyamide fiber by spinning with the number of filaments, the variation rate of the fineness was 2.4%. As shown in Table 1, the yarn breakage during spinning deteriorated, and the fineness unevenness of the obtained fiber deteriorated. In addition, as a similar structure of Comparative Example 1, the same results as described above were obtained in the spinneret in which the upper plate 22 and the lower plate 23 are completely coupled to form an integrated structure.
[Comparative Example 2]
In the spinneret 1 used in Example 1, the material of the lower plate 23 is changed to ceramic zirconium oxide, and the other is the same polymer, fineness and yarn using the same spinneret 1 as in Example 1. As a result of producing a polyamide fiber by spinning the number, a discharge rate of polymer discharge was generated due to variations in processing accuracy of the diameter and length of the discharge hole 20, and the fineness variation rate was 1.6%. As shown in Table 1, although the fineness unevenness of the obtained fiber was good, the yarn breakage during spinning deteriorated. Further, as a similar structure of Comparative Example 2, the same result as above was obtained also in the spinneret in which the upper plate 22 and the lower plate 23 are completely coupled to form an integrated structure.
[Summary]
In the comparison between Example 1 and Comparative Example 1, by changing the material of the upper plate 22 from SUS630 (heat treatment H1075) to ceramic zirconium oxide, temperature spots are less likely to propagate to the introduction hole 21, and as a result, the polymer The discharge flow rate unevenness was reduced, and fineness unevenness could be suppressed.

  Further, in the comparison between Example 1 and Comparative Example 2, the processing accuracy of the hole diameter and the hole length of the discharge hole 20 is improved by changing the material of the lower plate 23 from ceramic zirconium oxide to SUS630 (heat treatment H1075). Moreover, the generation | occurrence | production of the crack at the time of nozzle | cap | die cleaning, a crack, etc. can be suppressed, As a result, the discharge flow spot of a polymer was reduced and the fineness spot could be suppressed.

  The present invention is not limited to the method of manufacturing the spinneret and multifilament yarn used in the solution spinning method, but can be applied to the method of manufacturing the spinneret and multifilament yarn used in the wet spinning method and the dry and wet spinning method. Yes, but the scope of application is not limited to these.

DESCRIPTION OF SYMBOLS 1 Spinneret 2 Spinning hole 3 Heat retaining collar 4 Introduction part 5 Orifice part 6 Holding plate 7 Heating wire 8 Heating wire burying groove 9 Temperature controller 10 Temperature sensor 11 Discharge hole start end part 12 Laminated member 13 Heater member 14 Lead wire 15 Upper mouthpiece 16 Lower base 17 Introduction / guide hole 18 Ceramic nozzle tip 19 Perforated plate 20 Discharge hole 21 Inlet hole 22 Upper plate 23 Lower plate 24 Intermediate plate 25 Intermediate introduction hole 26 Spin pack 27 Spin block 28 Cooling device 29 Packing 30 Air layer 31 Metering hole 32 Base lower surface 33 Base upper surface 34 Outer peripheral layer 35 Steam applicator ΔηL Melt viscosity difference at temperature difference ΔT in low shear region ΔηH Melt viscosity difference at temperature difference ΔT in high shear region

Claims (7)

A spinneret provided with spinning holes for spinning a polymer as a filament yarn, which satisfies the following requirements (1) to (4):
(1) The spinning hole includes at least an introduction hole, and a discharge hole that is arranged downstream of the introduction hole in the spinning path direction of the polymer and discharges the polymer from the lower surface of the spinneret. To be done.
(2) The spinneret includes at least an upper plate in which the introduction hole is disposed and a lower plate in which the discharge hole is disposed.
(3) The cross-sectional area of the introduction hole in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole in the direction perpendicular to the polymer spinning path direction.
(4) The thermal conductivity of the upper plate is smaller than the thermal conductivity of the lower plate. A spinneret provided with spinning holes for spinning a polymer as a filament yarn, which satisfies the following requirements (1) to (4):
(1) The spinning hole includes at least an introduction hole, and a discharge hole that is arranged downstream of the introduction hole in the spinning path direction of the polymer and discharges the polymer from the lower surface of the spinneret. To be done.
(2) The spinneret includes at least an outer peripheral layer that forms the introduction hole and a lower plate on which the discharge hole is disposed.
(3) The cross-sectional area of the introduction hole in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole in the direction perpendicular to the polymer spinning path direction.
(4) The thermal conductivity of the outer peripheral layer is smaller than the thermal conductivity of the lower plate. A spinneret provided with spinning holes for spinning a polymer as a filament yarn, which satisfies the following requirements (1) to (4):
(1) The spinning hole includes at least an introduction hole, an intermediate introduction hole disposed downstream of the introduction hole in the direction of the polymer spinning path, and a spinning path of the polymer from the intermediate introduction hole. And a discharge hole which is disposed on the downstream side in the direction and discharges the polymer from the lower surface of the spinneret.
(2) The spinneret includes at least an upper plate provided with the introduction hole, an intermediate plate provided with the intermediate introduction hole, and a lower plate provided with the discharge hole. thing.
(3) The cross-sectional area of the introduction hole in the direction perpendicular to the polymer spinning path direction is larger than the cross-sectional area of the discharge hole in the direction perpendicular to the polymer spinning path direction.
(4) The thermal conductivity of the intermediate plate is smaller than the thermal conductivity of the lower plate. An intermediate plate having an intermediate introduction hole for connecting the introduction hole and the discharge hole is provided, and the thermal conductivity of the intermediate plate is smaller than the thermal conductivity of the lower plate. Spinneret described in 1. The spinneret according to claim 3 or 4, wherein a gap is provided in the intermediate plate as means for reducing the thermal conductivity of the intermediate plate. The spinneret according to any one of claims 1 to 5, wherein a metering hole is disposed in a part of the introduction hole in a spinning path direction of the polymer. A method for producing a filament yarn, wherein a multifilament yarn is produced using the spinneret according to claim 1.

Images