JP2854270B2 - Method for producing polypropylene-based high crimped composite filament yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to a high winding method for manufacturing a compressible composite filament yarns with the yarn crimp imparting device, more particularly continuously following the spinning and drawing processes of the polypropylene yarn polypropylene with crimp imparting apparatus suitable subjected to crimping processing method for producing a highly crimpable conjugate filament yarn.

[0002]

2. Description of the Related Art Conventionally, in order to develop a crimp on a yarn, the yarn is first subjected to a stretching treatment, and then the drawn yarn is wound once. Had been subjected to relaxation heat treatment. However, according to this method, the work procedure is long and takes a lot of time, so that the product cost increases.

Further, in order to cause the polypropylene fiber to exhibit crimp, composite fibers comprising a high-shrinkage component and a low-shrinkage component and comprising a polypropylene having a difference in melt index between both components have been widely used. However,
If polypropylene with a low melting point is used in the first place, it must be stretched at a low temperature, so that it will be drawn at a low magnification and only fibers with low strength will be obtained, and the same high elongation as ordinary polypropylene filament yarn will be obtained. Can not. Further, the mere difference in the melt index is not enough for the difference in the thermal shrinkage between the two fibers, and it is not possible to impart a good crimping ability to the yarn composed of these composite fibers.

On the other hand, for example, JP-A-2-191720 discloses a polypropylene having a specific Q value (weight average molecular weight / number average molecular weight) and a melt index, and a polypropylene having a specific melt peak temperature and a melt index. A latently crimpable conjugate fiber comprising a propylene random copolymer is disclosed. This is to increase the heat crimpability by copolymerizing ethylene with one of the polypropylenes, and to increase the crimpability by increasing the heat shrinkage difference with the other fiber, that is, the polypropylene single fiber, and at the time of stretching. Stable cotton production is ensured by imparting gentle crimping or mechanical crimping by a stuffer box, etc., and sufficient crimping is exhibited even at low temperatures, and even when heated at high temperatures during stretching. A composite fiber which does not decrease the shrinkage is obtained.

Further, since the polypropylene-based composite fiber disclosed in the above publication has a small Q value, it is disclosed in, for example, Japanese Patent Application Laid-Open No. 5-78916 in order to avoid the restriction of the heat treatment temperature range during the crimping treatment. Is a composite fiber composed of an ethylene propylene random copolymer in which propylene is randomly copolymerized with 3 to 8% by weight of ethylene and an ethylene propylene random copolymer in which propylene is randomly copolymerized with 0 to 3% by weight of ethylene. The heat treatment temperature range at the time of crimp development treatment is not limited, its melt index is within the range of a specific numerical value, having a predetermined dry heat shrinkage ratio and crimp number, etc., stretchability, bulkiness And a conjugate fiber with high flexibility. This is intended to ensure a desired crimping performance by causing a difference in heat shrinkage between both fibers composed of two components obtained by copolymerizing ethylene with polypropylene in different ratios.

[0006]

The conjugate fibers disclosed in the above publications are intended to produce short fibers which are suitable as a constituent material such as a nonwoven fabric in the first place. After the stretching, a mechanical crimping treatment such as a stuffer box is performed, and thereafter, the fiber is cut into short fibers so as to sufficiently develop a potential crimp in a nonwoven fabric manufacturing process.

That is, these composite fibers are converted into short fibers before the potential crimping property is developed, and then the product (nonwoven fabric) is produced.
It is necessary to insert a mechanical crimping process and a filament cutting step between the stretching process and the crimping process by heating in order to develop crimping at the time of manufacturing. Further, if the mechanical crimping process and the process of developing the potential crimpability are to be performed without cutting the filament following the drawing process, a stuffer box is simply used as the mechanical crimping process. Unless another suitable mechanical crimping mechanism is adopted, it is necessary to continuously carry out mechanical crimping and latent crimp development victory after stretching unless otherwise adopted. Is almost impossible. As a result, the conjugate fibers disclosed in both publications have to separate the stretching step and the latent crimp development step as in the related art, resulting in reduced work efficiency and increased cost.

Accordingly, the present invention improves the working efficiency by simultaneously performing a latent crimping process and a mechanical crimping process after the yarn is stretched, thereby improving the working efficiency. An object of the present invention is to provide a polypropylene-based crimpable composite filament yarn having the same strength and elongation and having both good crimpability and bulkiness.

[0009]

In order to achieve the above object, the present invention provides at least a heat recovery method at a dry heat of 110 ° C.
Two types of polypropylene polymers with shrinkage of 5% or more
After melt-spinning so that the cross-sectional structure becomes a composite structure,
Stretching ratio 2-6 times, drawing temperature 70-115 ° C, heat
A stretching treatment is performed at a set temperature of 90 to 135 ° C.
Approximately the same as the running direction of the yarn in the yarn running path near the yarn entrance
Equipped with a feed nozzle that injects hot air in
At right angles to the running path of the yarn downstream of the
Has slits or holes to exhaust hot air radially
Using a yarn crimping device provided with a crimp nozzle portion,
A crimping treatment at a hot air temperature of 110 to 150 ° C and a relaxation rate of 20% or more
Polypropylene high crimp composite foil
The method for producing the filament is a first main configuration.

[0010] At least a yarn spun into a composite structure of two types of polypropylene polymers having a heat shrinkage of 5% or more at 110 ° C dry heat, and preferably, for example, a high shrinkage component at 230 ° C as a high shrinkage component. An ethylene propylene random copolymer having a melt index of 5 to 40 g / 10 min was used as a low shrinkage component at 230 ° C.
Melt index of 8 to 150 g / 10 min
After melt-spinning so that the cross-sectional structure becomes a composite structure, a draw ratio of 2 to 6 is applied to the yarn.
Times, stretching temperature 70-115 ° C, heat setting temperature 90-13
A method for producing a polypropylene-based high crimped composite filament yarn which is subjected to a stretching treatment at 5 ° C., and subsequently subjected to a crimping treatment at a hot air temperature of 110 to 150 ° C. and a relaxation rate of 20% or more using the above-described crimping device. Is provided. In this case, hot air pressure 3 ~
It is preferable to apply a crimp at 5 kg / cm ² , and it is preferable that the composite structure is a parallel type in order to realize a high crimp when a latent crimp is developed.

A yarn obtained by spinning a composite structure of the above two types of polypropylene-based polymer comprising a high-shrinkage component and a low-shrinkage component having a difference in heat shrinkage of 5% or more is subjected to a draw ratio following the spinning step. 2 to 6 times, stretching temperature 70 to 115 ° C,
Drawing is performed at a heat setting temperature of 90 to 135 ° C., followed by introduction into the hot air injection chamber of the yarn crimping apparatus of the present invention.

In the hot air jet chamber, hot air at a temperature of 110 to 150 ° C. is jetted at a hot air pressure of 3 to 5 kg / cm ² in a direction substantially the same as the running direction of the introduced yarn, thereby developing latent crimp. . Although the temperature of this hot air is substantially equal to the melting point of polypropylene and is higher than the melting point of ethylene propylene random copolymer, the yarn is always running, and the yarn is directly applied to surrounding high-temperature members. By not contacting, the ethylene propylene random copolymer component does not melt.

Subsequently, the yarn subjected to the latent crimping treatment is
The hot air is sent to a crimped nozzle portion having slits or holes for exhausting hot air in a direction substantially perpendicular to the running path of the yarn. The exhaust pressure of the hot air radially acts on the yarn reaching the crimp nozzle, disturbing the running of the yarn and removing the heat, thereby imparting mechanical crimp in addition to latent crimp.

At this time, the relaxation rate of the running yarn is 20% or more, and the crimp is favorably applied. Thus, according to the yarn crimping apparatus of the present invention, the yarn can be simultaneously subjected to both latent crimping and mechanical crimping at substantially the same processing speed as in the spinning and drawing processing steps. become able to. Therefore, in the present invention, there is no need to separate the stretching step and the crimping step, and the working efficiency is not reduced.

In particular, according to the present invention, since tension is not applied to the yarn by winding, the strength of the yarn is not unnecessarily reduced, and further, in the crimping device of the present invention, Because a latent crimp is developed under relatively high-temperature hot air, and the blown hot air is exhausted perpendicular to the traveling yarn, mechanical crimp is applied to the yarn,
The thread does not come into contact with other substances. Therefore, the yarn of the present invention has the same strength and elongation as ordinary polypropylene filament yarn, and also has both good crimpability and bulkiness.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view of a crimping device 1 used in the present invention. The illustrated crimping device 1 is entirely composed of a single housing, and the inside of the housing has a hot air introduction chamber 2 from above.
The mechanical crimping chamber 3 and the crimp fixing chamber 4 are sequentially arranged in the running direction of the yarn.

The hot-air introduction chamber 2 has a hot-air inlet 2a at a part of the side wall of the housing, and the hot-air inlet 2a is connected to an external hot-air supply device (not shown) for controlling a predetermined air pressure and temperature. The heated hot air is introduced into the hot air introduction chamber 2 through the hot air inlet 2a. Further, a yarn guide tube 5 penetrating in the vertical direction is provided in the yarn running portion of the hot air introduction chamber 2,
The yarn runs on the yarn guide tube 5 from above to below. The yarn guide tube 5 has a plurality of feed nozzle holes 5a formed at a substantially central portion of the hot air introduction chamber 2 so as to extend obliquely downward from the outer surface of the tube wall toward the inside from the outside. I have.

A crimping chamber 3 is arranged below the hot air introducing chamber 2. The crimping chamber 3 has a hot air exhaust port 3a on a side wall near the bottom of the housing, and a thread running portion of the crimping chamber 3 extends vertically through the crimping chamber 3 in a tubular shape. Is extended. The crimping nozzle 6 communicates with the yarn guide tube 5 extending into the introduction chamber 2.

FIG. 2 shows a cross-sectional view of the crimp nozzle 6. A thread running path 6a is formed at the center of the crimp nozzle 6, and a number of slits 6b are formed in the wall of the crimp nozzle 6 radially from the thread running path 6 over the entire length of the cylinder. The diameter of the yarn running path 6a of the crimp nozzle 6 is
It is set to be the same as the inner diameter of. This slit 6b
Instead of this, it is also possible to form a large number of exhaust holes at equal intervals over the entire length of the crimp nozzle 6.

A crimp fixing chamber 4 is provided below the crimping chamber 3. The crimp fixing chamber 4 is connected to an upper crimp nozzle 6. The diameter of the crimp fixing chamber 4 is the same as the diameter of the yarn running path 6 a of the crimp nozzle, but the downstream of the crimp fixing chamber 4 is downstream. The diameter is gradually increased in the vicinity of the yarn exit of the crimp fixing chamber 4, and the diameter of the yarn exit is set to be the same as the diameter of the yarn traveling path 6a. I have.

During operation of the crimping device 1, hot air having a predetermined temperature and pressure is introduced into the hot air introducing chamber 2 through the hot air introducing passage 2a. The hot air introduced into the introduction chamber 2 is jetted from a feed nozzle hole 5a formed in the yarn guide tube 5 into the yarn traveling path in the traveling direction.
The yarn is heated by the hot air while traveling in the yarn guide tube 5. At this time, even if the temperature of the hot air around the yarn has reached the melting point, the yarn travels in a converged state together with the hot air and does not come into contact with the wall surface of the traveling path 5a, and does not become a completely molten state. Further, since the running yarn is supplied to the yarn guide tube 5 by being over-fed, sufficient heat shrinkage is caused by the relaxation heat treatment up to the softening temperature as described above, and complete latent crimping treatment is performed. Will be applied.

The yarn which has been subjected to the latent crimping process is subsequently supplied to a yarn running path 6 formed in a crimping nozzle 6 in the crimping chamber 3.
a. The crimping nozzle 6 is connected to the yarn running pipe 5, and the hot air is directly introduced into the yarn running path 6a. In the crimping chamber 3, the hot air blows out from the thread running path 6 a to the crimping chamber 3 through a large number of slits 6 b radially formed over the entire length of the crimping nozzle 6.
Further, the air is exhausted to the outside of the crimp applying device 1 through the hot air exhaust port 3a.

In the crimping chamber 3, a strong radially outward exhaust pressure acts on the yarn traveling on the yarn traveling path 6a, and the vortex of air generated in the yarn traveling path 6a causes the air to flow. Twisting occurs and a mechanical crimp is applied. In this mechanical crimping treatment, the yarn does not interfere with any other member, and thus the strength of the yarn does not decrease.

The yarn is subsequently sent to the crimp fixing chamber 4. In the crimp fixing chamber 4, the diameter of the yarn traveling path is large,
The crimped and bulky yarn can run smoothly. The yarn is gradually removed from the heat while traveling in the identification chamber 4, and the crimped form is fixed.

In the crimping device 1 according to the present embodiment , the yarn is introduced at substantially the same running speed as the running speed in the spinning and drawing process, and the drawing speed from the crimping device 1 is reduced. If appropriately set, since the latent crimping process and the mechanical crimping process can be performed simultaneously without generating excessive tension on the running yarn, the spinning and the stretching process are continuously performed. A crimping process can be performed. for that reason,
There is no need to separate the stretching step from the latent crimp development step and wind up the yarn after the stretching treatment, so that the working efficiency is not reduced. In addition, since no forcible tension acts on the yarn due to winding, the strength of the yarn is not unnecessarily reduced.

The above-described crimping device 1 is suitable for producing the polypropylene-based high crimping composite filament yarn of the present invention. In the present invention, in order to impart crimpability to the polypropylene filament yarn, a polymer having a high shrinkage component and a polymer having a low shrinkage component are melt-spun so that the cross-sectional structure becomes a parallel composite structure. In order to obtain more preferable crimpability, the difference in the heat shrinkage at 110 ° C. between the high shrinkage component polymer and the low shrinkage component polymer must be 5% or more. Examples of a combination of polymers satisfying this condition include an ethylene propylene random copolymer and polypropylene. In the ethylene propylene random copolymer, the content of propylene is preferably 93 to 97% by weight, and the content of ethylene is preferably 3 to 7% by weight. The ratio of the content, in consideration of the fact like the melting start temperature the thermal shrinkage becomes large when increasing the concentration of ethylene is reduced, it is set.

FIG. 3 is a graph showing the relationship between the thermal stress and the temperature of the ethylene propylene random copolymer and the polypropylene polymer, and FIG. 4 is a graph showing the relationship between the thermal shrinkage and the temperature.

In the polypropylene-based high-crimp composite filament yarn of the present invention, an ethylene propylene random copolymer having a large shrinkage functions as a high shrinkage component, and polypropylene having a small shrinkage functions as a low shrinkage component.
The difference in shrinkage at 110 ° C. between the respective polymers is close to about 10%, which sufficiently satisfies the 5% condition of the present invention. Also, even if the ethylene propylene random copolymer and polypropylene are spun under ordinary spinning conditions of polypropylene, a dry heat temperature of 130 ° C. and 35
% Or more.

As described above, since the difference in heat shrinkage between the ethylene propylene random copolymer and the polypropylene is large, excellent crimping is realized, and it is possible to obtain the same high elongation as a normal polypropylene filament yarn. .

In order to obtain a filament having a desired crimpability, there is no particular limitation except that the difference in shrinkage at 110 ° C. according to the present invention is 5% or more. A polymer can be appropriately selected from requirements. 110 ° C
Other combinations of polymers having a difference in shrinkage of 5% or more include polyethylene terephthalate as a low shrinkage component, polyethylene terephthalate modified with isophthalic acid, and polyethylene terephthalate modified with sodium sulfone isophthalic acid, and 2,2- Bis [4 '-(2-hydroxyethoxy) phenyl] propane modified polyethylene terephthalate;

Further, when ethylene propylene random copolymer and polypropylene are employed, JIS K7
The melt index (hereinafter referred to as the MI value) measured at 230 ° C. based on G.210 is 5 to 40 g / 10 min, preferably 10 for ethylene propylene random copolymer.
~ 40g / 10min, polypropylene is 8 ~ 150 /
When a polymer in the range of 10 min, preferably 30 to 130 g / 10 min is used, the crimping performance can be further improved.

If the MI value of the ethylene propylene random copolymer is less than 5 g / 10 min, the melting temperature must be set to a high temperature in order to lower the melt viscosity during spinning, and therefore, the stability in each step and the coloring property of the dye and pigment deteriorate. I do. On the other hand, the MI value of polypropylene is 150 g / 10 m.
When the value exceeds in, the stability of passing through the process deteriorates and the fiber strength also decreases. Further, as the difference between the MI value of the ethylene propylene random copolymer and that of the polypropylene becomes larger, the crimp development becomes larger, but on the other hand, the passage stability in the process is reduced. The above-described range of the MI value is determined in consideration of these characteristics.

The fineness of the filament constituting the polypropylene-based high crimping composite filament yarn of the present invention is not limited, and any fineness can be set. However, the relationship between the fineness and the MI value of the polymer is as follows. In consideration of the passage stability of the process, it is preferable to select a polymer having a low MI value in the case of a filament having a large fineness, and to select a polymer having a high MI value in the case of a filament having a small fineness.

In the production of the highly crimped composite filament yarn of the ethylene propylene random copolymer and polypropylene according to the present invention, the composite ratio (weight ratio) of the ethylene propylene random copolymer component and the polypropylene component is set to 75/25 to 25/75. Extruder temperature 200-2
The composite spinning is performed in parallel by a melt spinning method at 80 ° C. and a spinning speed of 300 m / min or more to obtain a drawn undrawn yarn.

The obtained undrawn yarn is drawn at a magnification of 2 to 6 times, at a drawing temperature of 70 to 115 ° C., at a heat setting temperature of 90 to 135 ° C., and then heat-treated at a heat treatment temperature of 100 to 135 ° C. by the above-described crimping device. The crimping treatment is performed at 150 ° C. and a relaxation rate of 20% or more.

In the stretching treatment, if the draw ratio is less than 2 times, the strength of the obtained filament yarn is reduced and the elongation is increased, so that the expression of crimp is reduced. Decrease. If the stretching temperature is lower than 70 ° C., the stretching of the filament yarn is not performed at a high magnification, and the strength of the filament yarn is reduced, and the occurrence of crimp is reduced. When the heat setting temperature is lower than 90 ° C., the shrinkage ratio of the low shrinkage component increases, and the difference in the shrinkage ratio between the high shrinkage component and the low shrinkage component becomes small, so that the occurrence of crimp decreases. On the other hand, when the temperature exceeds 135 ° C., the relaxation rate decreases, so that the occurrence of crimp decreases.

In the crimping treatment, the heat treatment temperature is 100 ° C.
If the temperature is less than 150 ° C., the expression of crimp is small. The relaxation rate is 20
If it is less than 10%, it is difficult to obtain a highly crimped composite filament yarn which has little crimp expression and can be said to be a highly crimped composite filament yarn. Although the crimping performance increases as the relaxation rate increases, the stability of the passage through the process decreases. Therefore, the relaxation rate is preferably set to 35% or less.

In the present invention, even if the fiber cross-section of the filament yarn is not only a circular cross-section, but also an irregular cross-section such as a triangular cross-section, the crimp developing property is not impaired. In addition, even with the original fiber containing a color pigment, sufficient crimping ability can be obtained.

Hereinafter, examples of the present invention will be specifically described with reference to comparative examples. Table 1 shows the physical properties of the yarns obtained in Examples and Comparative Examples of the present invention, Table 2 shows the crimping properties, and Table 3 shows the bulkiness. Here, as a reference for comparison, Table 1 shows measured values of crimped filament yarns of 800d / 36f indentation-type simultaneous drawing hot air processing obtained from propylene only.
To 3 are shown as plain yarns.

The crimp rate and bulkiness of the yarn were measured by the following methods. Crimp ratio: A bunch of samples is created by bundling the samples. The sample is dry heat treated at 130 ° C. for 10 minutes. Leave for 10 minutes or more after heat treatment. A measurement load A is applied to one end of the sample yarn, and the yarn length (L ₁ ) is measured one minute later. Measurement load A = denier × 1/10 × (2 × number of windings) Except for measurement load A, leave for 2 minutes. A measurement load B is applied to one end of the sample yarn, and the yarn length (L ₂ ) is measured one minute later. Measurement load B = denier × 1/1000 × (2 × number of turns) Calculation formula: Crimp rate (%) = [(L ₁ −L ₂ ) / L ₁ ]
The numerical value calculated by × 100 is defined as the crimp rate.

Bulkiness: A bunch-like sample is made by bundling the samples. The scab sample is placed on the measuring table and the initial load A for measurement is placed. The measuring table is shown in FIG. Initial load of measurement = 20 g. One minute later, the height (H ₁ ) of the sample is read. A measurement positive load B is placed on the measurement initial load A. Measurement positive load = 200 g After 1 minute, the height (H ₂ ) of the sample is read. The sample protruding from the sample stage is cut off, and the weight (Xg) of the remaining sample is measured. Calculation formula: The numerical value calculated according to bulk volume V (cm ³ / g) = 4H / X is used as an index of bulkiness.

Example 1 An ethylene propylene random copolymer (EP) having an MI of 17 g / 10 min and MI
Using 30 g / 10 min of propylene (PP), the extruder temperature of the EP was increased to 230 ° C. in the first zone,
Zone 240 ° C., PP extruder temperature in first zone 220
C., the second to fourth zones were set at 230.degree. C., the spinning temperature was 240.degree. C., and the parallel composite spinning was performed at a spinning speed of 300 m / min. The obtained undrawn yarn was drawn at a draw ratio of 4.348 times and at a draw temperature of 1.
The film is stretched at 05 ° C. and a heat setting temperature of 125 ° C., and a relaxation rate of 33%, a hot air temperature of 145 ° C., and a hot air pressure of 4.degree.
Heat treatment was performed at 0 kg / cm ² to obtain a crimped yarn having a circular cross section of approximately 680 d / 60f. The obtained fiber was in a good crimped state, and the stability during the process was good. The filament yarn according to the present invention was a yarn having high crimpability while having ordinary high elongation.

Example 2 The same treatment as in Example 1 was carried out except that the same EP and PP as the raw materials used in Example 1 were used, and the cross-sectional shape of the fiber was changed to a triangular cross section.
As a result, a filament yarn having a triangular cross section f was obtained. The resulting fibers exhibited good crimping properties and also had good yarn-making stability.

[Example 3] As denier of Example 1, the same EP and PP as in Example 1 were used, the extruder temperature was the same as in Example 1, and spinning was performed at a spinning speed of 700 m / min.
The film is stretched at a stretching ratio of 2.58 times, at a stretching temperature of 105 ° C. and a heat setting temperature of 125 ° C., using a crimping apparatus shown in FIG. 1 and having a relaxation rate of 27%, a hot air temperature of 145 ° C., and a hot air pressure of 3.5 kg / cm.
Heat treatment was performed at ² to obtain a filament yarn of about 200d / 30f. The resulting fiber exhibited good crimping properties and good stability in the process.

Example 4 As a raw material, MI was 40 g /
Using EP of 10 minutes and PP of MI of 130 g / 10 minutes, the extruder temperature of EP was set to 200 ° C. in the first zone,
4 zone 220 ° C, PP extruder temperature in first zone 19
The spinning was set at 0 ° C., the second to fourth zones at 200 ° C., and the spinning temperature at 220 ° C., and the spinning speed was 700 m / min. The obtained undrawn yarn was drawn at a draw ratio of 3.23 times, a drawing temperature of 90 ° C, and a heat setting temperature of 110 ° C.
Relaxation rate 28%, hot air temperature 145 ° C, hot air pressure 3.2kg / cm ²
To give a filament yarn of about 120d / 30f. The resulting fiber exhibited good crimping properties and good stability in the process.

Comparative Example 1 PP with MI of 30 g / 10 min
The temperature of one extruder was set to 200 ° C. in the first zone, 210 ° C. in the second to fourth zones, and the temperature of the other extruder was set to 210 ° C. in the first zone, 240 ° C. in the second to fourth zones, and the spinning temperature was 220 ° C.
The spinning was performed at a spinning speed of 700 m / min. The obtained undrawn yarn was drawn at a draw ratio of 2.69 times, a drawing temperature of 90 ° C., and a heat setting temperature of 110 ° C.
%, Hot air temperature of 145 ° C. and hot air pressure of 4.5 kg / cm ² to obtain a filament yarn of about 180 d / 30 f. The obtained fiber was a yarn having insufficient crimping properties and bulkiness.

[Comparative Example 2] PP of 8 g / 10 min and MI of 5 g / 10 min was used.
Extruder temperature in the first zone 220 ° C,
In four zones at 245 ° C., PP with an MI of 5 g / 10 min was used.
° C, the spinning temperature is set to 215 ° C, and the spinning speed is 400 m /
And the obtained undrawn yarn is drawn at a draw ratio of 2.24.
The film is stretched at a stretching temperature RT and a heat setting temperature RT, and the relaxation rate is 40%, the hot air temperature is 145 ° C., and the hot air pressure is 5.0 in the apparatus of FIG.
It was treated at kg / cm ² to obtain about 970d / 60f filament yarn. The yarn had low strength and high elongation, and was not suitable for practical use.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

According to the table, first, when Examples 1 to 4 are compared with Comparative Examples 1 and 2, Examples 1 to 4 show that EP and PP each having a large difference in heat shrinkage rate between the high shrinkage component and the low shrinkage component. And Comparative Examples 1 and 2 both use polypropylene. Comparative Example 1 has the same strength and elongation as those of Examples 1 to 4, but has much lower bulkiness and crimpability. On the other hand, Comparative Example 2 is Examples 1-4.
Compared with, the crimpability and bulkiness are imparted considerably, but this is because the relaxation rate in the crimping treatment is increased to 40%, and the strength and elongation are considerably reduced. .

From the above, in order to obtain good bulkiness and crimp characteristics while maintaining yarn properties such as strength and elongation, the difference in heat shrinkage between the high shrinkage component and the low shrinkage component is considered. It turns out that the use of a large polymer is the most important condition.

When Examples 1 and 2 are compared, the drawing conditions and the crimping conditions are the same except that the cross section of the yarn is circular and triangular. Since Examples 1 and 2 are equivalent in any of the yarn physical properties, crimping characteristics, and bulkiness, it can be understood that these characteristics are not affected by the cross-sectional shape of the yarn.

[0054]

Crimping apparatus used with the present invention, since it is possible to perform stretching a continuously latent crimp processing and mechanical crimped simultaneously after applying the yarn, after stretching There is no need to wind up once, which saves labor and time, and does not impose a load such as a pulling force on the yarn even during continuous processing. Furthermore, in the crimping device, a desired latent crimping process and a mechanical crimping process can be simultaneously performed simply by introducing hot air of a predetermined temperature and pressure and running the yarn with the same hot air. Therefore, the strength of the yarn is sufficiently maintained without the yarn rubbing against other members.

Further, the polypropylene obtained by the present invention
110 ° C. for lenticular crimpable composite filament yarn
Types of propyle with a difference in heat shrinkage of 5% or more
Temperature of 230 ° C
Melt index of 5-40g / 10min
When using ethylene propylene random copolymer,
In addition, as a low shrinkage component,
8 to 150 g / 10 min polypropylene polymer
And spinning so that the cross-sectional structure becomes a composite structure
After that, the yarn is drawn at a draw ratio of 2 to 6 times at a draw temperature of 70 to 11
Stretched at 5 ° C, heat setting temperature 90-135 ° C
Subsequently, using the yarn crimping device, the hot air temperature
At a temperature of 110 to 150 ° C and a relaxation rate of 20% or more.
By doing so, in addition to having the same strength and elongation as ordinary polypropylene filament yarn, it also has good crimpability and bulkiness. Therefore, it is suitable as a material in the field of industrial materials, and it can be used as a material for knitting and knitting. It can also be used for knitted fabrics, carpets with a voluminous feel and high resilience, and is useful as a material to be used in various fields including the industrial materials field.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a crimp applying device of the present invention.

FIG. 2 is a cross-sectional view of a crimp nozzle portion of the crimp applying apparatus of the present invention.

FIG. 3 is a graph showing a relationship between thermal stress and temperature of an ethylene propylene random copolymer and a polypropylene polymer.

FIG. 4 is a graph showing the relationship between the thermal shrinkage of ethylene propylene random copolymer and polypropylene polymer and temperature.

FIG. 5 is a schematic view of a measuring table used for evaluation of bulkiness.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crimp giving apparatus 2 Hot air introduction chamber 2a Hot air introduction port 3 Crimp chamber 3a Hot air exhaust port 4 Crimp fixing room 5 Thread guide tube 5a Feed nozzle hole 6 Crimp nozzle 6a Thread running path 6b Slit

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akira Imaizumi 4-160 Sunadabashi, Higashi-ku, Nagoya City, Aichi Prefecture Mitsubishi Rayon Co., Ltd. Product Development Laboratory (56) References JP-A-53-38737 (JP, A JP-A-53-38737 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D02G 1/00

Claims (4)

(57) [Claims] 1. At least heat collection at 110 ° C.
Two types of polypropylene polymers with shrinkage of 5% or more
After melt-spinning so that the cross-sectional structure becomes a composite structure,
Stretching ratio 2-6 times, drawing temperature 70-115 ° C, heat
A stretching treatment is performed at a set temperature of 90 to 135 ° C.
Approximately the same as the running direction of the yarn in the yarn running path near the yarn entrance
Equipped with a feed nozzle that injects hot air in
At right angles to the running path of the yarn downstream of the
Has slits or holes to exhaust hot air radially
Using a yarn crimping device provided with a crimp nozzle portion,
A crimping treatment at a hot air temperature of 110 to 150 ° C and a relaxation rate of 20% or more
Polypropylene high crimp composite foil
A method for producing a filament yarn. 2. The yarn has a high shrinkage component of 230 ° C.
Has a melt index of 5 to 40 g / 10 min.
When using ethylene propylene random copolymer
In both cases, melt index at 230 ° C was used as a low shrinkage component.
8 to 150 g / 10 min polypropylene poly
The method for producing a polypropylene-based highly crimped composite filament yarn according to claim 1, wherein the filament is a mer . Wherein at 3. A thermal wind pressure 3-5 kg / cm ² Mekuchijimizuke
3. The high crimped composite polypropylene fiber according to claim 2,
A method for producing a filament yarn. 4. The composite structure according to claim 3, wherein said composite structure is of a parallel type.
Of high crimped composite filament yarn of polypropylene
Method.