JPS62250213A - Spinning block for melt spinning - Google Patents

Abstract

PURPOSE:To obtain yarn having optimum physical properties of yarn in good spinning stability, by setting a cylindrical heater in a distance from the under surface of a spinneret attached to a spinning block in such a way that spun yarn is surrounded by the heater and making the surface temperature distribution of the yarn variable in the longitudinal direction. CONSTITUTION:A cylindrical heater 11 is fixed through a heat insulating material 10 to the under surface of a spinning pack 3 set in a spinning block 1 and the outside of the heater is covered with a heat insulating material 12. The heater is positioned 10 in 10-200mm range from the under surface of a spinneret 7 of the heater 11 and a heater strand is properly arranged in order to make the surface temperature distribution of the heater 11 variable in the longitudinal direction of spun yarn 9.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a spinning device for synthetic fibers, and more specifically to a method for controlling the temperature of the atmosphere below a spinneret attached to a spin block for melt spinning. The present invention relates to a novel spin block for melt spinning that can vary the stacking ratio in the longitudinal direction of the yarn.

(Prior Art) Generally, a spin block for melt-spinning synthetic fibers is heated directly or indirectly by a heating liquid of a liquid heating medium, a heated vapor of a heating medium, or an electric heater.
A spinning bag is mounted within the spin block, and the temperature of the spinning bag is kept constant, albeit passively, by heat transfer from the spin block. A predetermined amount of molten polymer is discharged from a nozzle attached to the lower part of the spinning bag to make it fine.

After a cooling process, it is taken off at a predetermined speed to become synthetic fibers.

The region where the molten thread discharged from the nozzle becomes thinner is an area generally surrounded by a heat insulating material attached to the bottom surface of the spin block. It is the temperature that is the result of balancing the amount of heat required to raise the temperature of the air flowing into the area from below to compensate for the accompanying flow of the molten thread, and the release of the heat insulating material. Desired yarn properties are obtained by changing the temperature by passive means such as changing the length in the yarn direction or changing the spatial volume within the region.

On the other hand, various methods have been proposed in which a heating area is provided directly below the spinneret and the temperature of the region is actively controlled to control the orientation of the spun yarn.
There is no mention of the relationship between the temperature of the molten polymer and the temperature in the above region or the temperature distribution in the yarn direction in the region.

It is well known that increasing the temperature in the above region suppresses crystallization accompanying the orientation of the spun yarn and improves high-speed spinnability. Cooling tends to cause unevenness in the denier of the wound yarn, and there are limits to slow cooling as well as to the length of slow cooling. Currently, filaments for clothing have particularly strict requirements for denier unevenness, and no effective slow cooling means have yet been found.

In addition, the higher the temperature of the die surface, the slower the formation rate of foreign matter adhering to the spinneret surface, the less unevenness of discharge at the discharge hole, the less yarn breakage, etc., and the better the spinning stability is. In addition, the spinnability and physical properties of the spun yarn are mainly influenced by the temperature of the spun yarn and the spinneret.
From the viewpoint of preventing thermal deterioration and thermal decomposition of the molten polymer, the lower the temperature in the transportation route until it is discharged, the more preferable it is.

(Objective of the Invention) The present invention solves the above-mentioned drawbacks of the prior art, and at the same time actively controls the atmospheric temperature under the spinneret, including the important thinning step in the spinning technology, which could not be achieved with the prior art. The purpose is to obtain spinning stability and optimum yarn physical properties, and also to obtain yarns with various physical properties using the same spin block to meet the demand for a wide variety of products in small quantities.

(Structure of the Invention) In order to achieve the above object, the present inventors have arrived at the present invention as a result of intensive studies, and the present invention provides a spin block for melt-spinning synthetic fibers. 1000 wI from the board surface 200. A spin block for melt spinning, characterized in that a cylindrical heating heater is provided so as to surround the spun yarn within a range of be.

(Embodiments of the Invention) The present invention will be described in more detail below with reference to the drawings, but it goes without saying that the present invention is not limited to the following actual IM embodiments.

FIG. 1 shows a cross section of a spin block for melt spinning according to the present invention, and FIGS. 2 and 3 are perspective views of the entire heater wire wiring diagram of a heating heater.

In FIG. 1, an internal space 2 of a spin block 1 is filled with heated vapor of a heating medium, and is maintained at a constant temperature by a heating means (not shown). The spinning bag 3 is attached so that its outer surface is surrounded by the spin block 1, and an intake member 4 for polymer metered and discharged from a spinning pump (not shown) is provided on the top of the spinning bag 3, and the polymer is introduced into the spinning bag 3. The filter layer 5. Uniform dispersion plate 69 Rokin 7
The fibers are discharged from the spinneret hole 8 and formed into a thread 9.

On the other hand, a heating heater 11 is attached to the lower surface of the spinning pack 3 so as to surround the spun yarn 9 via a heat insulating material 10, and a heat insulating material 12 is installed on the outside of the heating heater 11. It is designed to be detachable from the bag 3. In addition, a heat insulating material 13 is provided on the bottom surface of the spin block 1.
is attached to surround the heat insulating material 12.

The heating heater 11 is provided in the range of 10#ll11 to 2008 from the bottom surface of the spinneret 7 in the longitudinal direction of the spun yarn, and power is supplied from the terminals 14 and 15, and a predetermined temperature is obtained at the temperature detection terminals 16 and 17. It's controlled like that.

The detection position of the temperature detection ends 16 and 11 is the heating heater 11
It may also be a part of the space 19 under the spinneret that slightly protrudes from the heating heater 11 so long as it does not touch the spun yarn.

Heating heater 1 of heater wire 18 for making the surface temperature distribution of heating heater 11 variable in the longitudinal direction of the spun yarn
An example of the arrangement within 1 is shown in Figure 2 +a+, (b+. Figure 2 (
ω has a structure in which the heater element 18a is commonly disposed over the entire length of the heater 11, the heater element 18b is disposed only in the upper part, and the surface temperature of the beginning of the heater 11 is high; Figure +b+ shows the heater wire 18
c and 18d, the surface temperature of the heating heater 11 can be made uniform in the longitudinal direction of the yarn, and the lower part can be heated to a high temperature.

It is common to increase the temperature closer to the cap.

FIG. 3 shows an example of application of the present invention to a multi-spindle spinning bag, in which a large number of heating elements 22 are embedded in a heating heater 21 provided with a space 20 corresponding to each spun yarn. As one heating element group A, they are connected to the same power source in the transverse direction, and in the longitudinal direction of the yarn, the heating element groups B, C, and D are connected to separate power sources, and as a whole, heaters are connected in the longitudinal direction of the yarn. The surface temperature distribution is made variable. In order to obtain temperature uniformity in the lateral direction, it is also preferable to vary the capacity of the heating elements within the heating element group, and when changing the temperature distribution in the longitudinal direction, the surface temperature distribution of the heater should be determined in advance. By embedding groups of heating elements with different capacities, the entire heater can be powered by the same power source.

(Effect of the invention) The physical properties of the yarn 9 spun from the spinneret 7 are largely influenced by the temperature of the spinneret 7 and the temperature of the space below the spinneret, but
According to the present invention, since the surface temperature distribution of the heating heater can be made variable in the longitudinal direction of the spun yarn, the above-mentioned temperature can be changed regardless of the temperature of the spin block 1, and the physical properties of the spun yarn can be controlled. Alternatively, it will be possible to prevent thermal deterioration of molten polymers.

The physical property control of the spun yarn will be explained in more detail. Generally, when the spun yarn is taken off at a speed of 3000 TrL/min or more, crystallization is promoted due to the orientation of the polymer, making it difficult to draw the yarn after it has been taken off.
It becomes difficult to improve the elongation (elongation, etc.), but it has been found that this phenomenon of oriented crystallization is greatly influenced by the temperature condition after about 10 rIuR below the spinneret, and the subsequent temperature drop condition can be measured in the longitudinal direction of the yarn. It has also been found that even better results can be obtained by slowing down within a certain range. The range is 10.
to 200rnIR, and 200. If the temperature is higher than that, the temperature drop rate of the spun yarn becomes too slow, and denier unevenness of the yarn becomes noticeable, resulting in a decrease in quality as a filament for clothing.

On the other hand, from the viewpoint of preventing thermal deterioration of the molten polymer, even if the temperature of the spin block 1 is lowered to transport the polymer at a low temperature, if the polymer is sent to the conventional spin block, the temperature of the spinneret 7 will drop, causing problems with threadability and yarn strength. However, according to the present invention, the above-mentioned problems are solved because the upper part of the heater 11 can be brought to a high temperature state preferentially, the temperature of the cap 7 can be increased, and the atmospheric temperature under the cap can be controlled simultaneously. It also has the advantage of being

Also, regarding the problem of foreign matter adhering to the cap 7, a higher temperature of the cap is preferable, but it is even more desirable if the atmosphere under the cap can be replaced. However, in conventional spin blocks, the atmosphere temperature under the nozzle is maintained only by heat dissipation from the bottom surface of the spinning pack and heat radiation by cooling the polymer, so it is not possible to unnecessarily improve the replaceability of the atmosphere under the nozzle. . With the configuration of the present invention, this can be easily carried out by increasing the temperature of the heater by an amount corresponding to the amount of heat required to raise the temperature of the replacement gas.

The heater used in the present invention is generally an electric heater incorporating a heating element as described above, but if a more localized temperature gradient is desired, a ceramic heater or Direct energization type heaters can be used.

Further, when a gradual temperature gradient in the longitudinal direction is required, the object of the present invention can also be achieved by enclosing an aquarium or inorganic heating medium in a heating heater or the like and laminating two or more of them.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the present invention, Fig. 2 (J and (b)) is an explanatory diagram of the wiring of the heating wire of the heating heater. Fig. 3 is a schematic perspective view showing another embodiment of the heating heater. 1: Spin block, 3: Spinning novel. 7: Spinneret, 11: Heater 1f-1 (a) (b)
Early drawing 2

Claims (4)

[Claims] (1) In a spin block for melt-spinning synthetic fibers, 10 m from the bottom surface of the spinneret attached to the spin block.
For melt spinning, characterized in that a cylindrical heating heater is provided so as to surround the spun yarn within a range of 200 mm from m to 200 mm, and the surface temperature distribution of the heater is made variable in the longitudinal direction of the spun yarn. spin block. (2) The spin block for melt spinning according to claim 1, wherein the heating heater is an electric heating heater. (3) The spin block for melt spinning according to claim 1, wherein the heating heater is a ceramic heater. (4) The spin block for melt spinning according to claim 1, wherein the heating heater is a heating body containing at least two types of heating medium.