JPH11263534A - Acrylic filament package and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give a proper winding shape even to a filament package with an acrylic filament of 120 kg or more winding amount wound round a core bobbin, and prevent the package from getting out of lease at the time of reeling it off. SOLUTION: This acrylic filament package of cylindrical shape, which has a core bobbin on which an acrylic filament is wound up into a cylindrical form, has a filament traverse width L of 550 mm or more, a ratio of the outside package diameter D to the traverse width L of 0.9 to 1.4, a lease winding angle of 6 to 8 deg., and a filament winding amount of 120 kg or more per package. The manufacturing method of such an acrylic filament package changes the winding ratio where an acrylic filament is wound up round a core bobbin two or more times so that the lease winding angle is regulated in the range of 6 to 14 deg., and also takes the thread line up at an initial tension of 60×10<-5> to 150×10<-5> N/denier and a tension at 120-kg winding of 10×10<-5> to 100×10<-5> N/denier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acrylic yarn package, and more particularly to an acrylic yarn package capable of winding as much acrylic yarn per package as possible on a core bobbin, and a method of manufacturing the same. In particular, the present invention is suitable as an acrylic precursor yarn package used for carbon fiber production.

[0002]

2. Description of the Related Art Polyacrylonitrile-based long fibers are used not only for clothing but also in recent years as precursors for carbon fibers. In order to obtain carbon fibers with excellent performance and to increase their productivity. Many improved techniques have been disclosed.

[0003] The carbon fiber is once wound in a spinning process of spinning an acrylonitrile-based fiber yarn as a precursor thereof, and then sent to a firing process, where the fiber is heated and fired in an air atmosphere at 200 to 300 ° C to oxidize it. It is obtained through a carbonization step of heating to 300 to 3000 ° C in an inert atmosphere such as nitrogen, argon, helium, etc., and carbonizing by heating in an inert atmosphere such as nitrogen, argon, or helium. It is widely used for sports use, general industrial use, and the like.

[0004] In general, carbon fibers are composed of filaments having a single yarn number of 1000 or more, and a multifilament is used as one yarn unit. An acrylic yarn as a raw material is subjected to a firing step as a subsequent step. Due to the difference in the production yarn speed, it is general that the yarn is once wound up as a package in the yarn production process and then sent to the firing process. Therefore, the amount of acrylic yarn that can be processed at one time in the firing step is limited, and it is necessary to continuously tie or connect the yarns in order to increase the productivity.
Japanese Unexamined Patent Application Publication, No. Sho 61-20761 discloses an improvement technique for improving productivity. On the other hand, in order to increase the productivity in the firing step, it is an issue to increase the amount of acrylic yarn that can be processed at one time, in addition to the yarn joining technology described above. However, since the acrylic yarn is usually wound on a core bobbin, if a large amount of yarn is wound, the yarn may collapse or may fall off the package end surface during unwinding in the firing step, resulting in a 120 kN.
It was difficult to wind up a large amount of acrylic yarn of g or more.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an acrylic yarn package having a good winding shape and not falling off when unwinding when winding a large amount of acrylic yarn on a core bobbin, and a method of manufacturing the same. To provide.

[0006]

The acrylic yarn package of the present invention has the following structure to solve the above-mentioned problems. That is, a cylindrical package in which an acrylic yarn is wound around a core bobbin in a cylindrical shape, wherein the traverse width L of the yarn is 550 mm or more, and a ratio L / D of L to the outer diameter D of the cylindrical package. Is in the range of 0.9 to 1.4, the winding angle is in the range of 6 to 14 degrees, and the winding amount of the yarn is 120 kg or more per package. Such an acrylic yarn package, when winding the acrylic yarn around the core bobbin,
By changing the winding ratio a plurality of times, the winding angle is controlled in the range of 6 to 14 degrees, and the initial tension of the yarn is 6 degrees.
Acrylic-based, wherein the package is obtained by winding the package at 0 × 10 ^{−5 to} 150 × 10 ⁻⁵ N / denier, and at a tension of 120 × 10 ^{−5 to} 100 × 10 ⁻⁵ N / denier when winding 120 kg. It can be suitably obtained by a method for producing a yarn package.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

The acrylic yarn applied to the present invention is composed of a so-called acrylic polymer, for example, a polymer obtained by polymerizing 90% by weight or more and less than 10% by weight of acrylonitrile comonomer. Examples of the comonomer include acrylic acid, methacrylic acid, itaconic acid, or a methyl ester, an ethyl ester, a propyl ester, a butyl ester, an alkali metal salt, an ammonium salt, or allyl sulfonic acid, methallyl sulfonic acid, styrene sulfonic acid, Alternatively, one or more of these alkali metal salts can be used.

The acrylic polymer is obtained by a known polymerization method, for example, a polymerization method such as emulsion polymerization, suspension polymerization, solution polymerization, and the like. Further, when producing an acrylic fiber from these polymers, dimethylacetamide, A polymer solution using dimethyl sulfoxide (hereinafter, DMSO), dimethylformamide, nitric acid, zinc chloride, rodan soda aqueous solution or the like as a solvent is used as a spinning solution, and spun by a wet spinning method or a dry-wet spinning method. The spun yarn is then subjected to drawing in a bath. The drawing in the bath may be performed directly on the spun yarn, or may be performed after the spun yarn is washed once with water and the solvent is removed. Stretching in a bath is usually performed in a stretching bath at 30 to 98 ° C. under conditions of a stretching ratio of about 2 to 6 times. The yarn drawn in the bath is usually applied with an oil agent, dried and densified by a hot roller or the like, then subjected to steam drawing, and then wound around a core bobbin to form a package. When winding on a core bobbin, a plurality of yarns may be combined and then wound.

In the present invention, as shown in FIG. 1, the ratio L / D of the yarn traverse width L of the package to the diameter D of the cross section of the cylindrical package is 0.9 to 1.4, preferably 0.9 to 1.2.
By keeping L in a range of 550 mm or more, it is possible to wind a yarn of 120 kg or more. If the L / D is larger than 1.4, a large amount of yarn cannot be wound for the volume of the package, and the L / D is not more than 0.4.
If it is smaller than 9, the end face swelling amounts k1 and k2 shown in FIG.

If the package weight exceeds 100 kg, the core bobbin may be damaged due to tightening after winding the yarn or an impact at the time of handling. Therefore, the core bobbin is made of a fiber reinforced plastic (hereinafter, referred to as a core bobbin). F
RP). As reinforced fiber,
Glass fiber, carbon fiber, and other fibers are used,
Inexpensive glass fibers are preferably used. Further, carbon fibers capable of reducing the weight of the core bobbin are also more suitable. As a resin used for the FRP, an epoxy resin, a polyester resin, an unsaturated polyester resin, or the like is preferable. The length of the core bobbin may be arbitrarily determined as long as the L / D is satisfied. However, from the viewpoint of handling of the core bobbin, the length, diameter, and thickness are determined so as to be 10 kg or less per core bobbin. Good.

In the present invention, not only the L / D is kept in the above-mentioned range but also the winding angle on the package is in the range of 6 to 14 degrees, preferably 8 to 12 in order to wind a large amount of yarn. It is necessary to set in the range of degrees. Here, the twill angle is, as shown in FIG. 1, an angle θ between a straight line α perpendicular to the axial direction of the core bobbin 2 and the direction of the yarn 3 to be wound. When winding the yarn 3 around the core bobbin 2, if the yarn 3 is wound in the same direction as the straight line α perpendicular to the axial direction of the core bobbin 2 (that is, at θ = 0 degrees), the yarn is wound over one circumference of the core bobbin. It becomes impossible to take up a large amount of yarn. Therefore, it is common to wind the yarn while traversing the yarn in the axial direction of the core bobbin, and wind the yarn so that the straight line α and the yarn have an angle θ.

If the twill angle θ is less than 6 degrees, the thread will tend to drop off at the end face of the package.
If it is larger than the degree, the winding shape is broken and k1 and k2 shown in FIG. 1 become too large, which is not preferable.

Usually, when winding the yarn, the winding machine spindle and the traverse cam are connected to a pulley and a timing belt such that the number of revolutions of the winding machine spindle per one yarn traverse, that is, a so-called wind ratio, becomes constant. It is usually connected directly. When the wind ratio is constant, the twill angle decreases linearly as the diameter of the package wound on the core bobbin increases (curve (2) in the graph of FIG. 2). When winding a large number of yarns, if the winding ratio is constant, the twill angle at the end of winding becomes too small, and there is a problem that the twill drops easily during unwinding. Therefore, by changing the winding ratio during winding according to the yarn winding amount and winding while keeping the twill angle within the above range, a package in which the yarn twill drop is less likely to occur and the winding shape is less likely to collapse is provided. Obtainable. For this purpose, for example, the spindle drive and the traverse drive are made independent, and after detecting the spindle rotation speed, a calculation is performed so as to achieve a set wind ratio, and then a mechanism for controlling the traverse drive rotation speed is employed. In the process, the winding ratio can be freely set according to the winding amount, and the hoop angle on the package can be kept in the above range (curve (1) in FIG. 2). As described above, winding by changing the wind ratio a plurality of times changes the twill angle during winding and keeps L / D within the above range, whereby winding of 120 kg or more can be facilitated.

It is also important for the winding of 120 kg or more to optimize the initial tension of the yarn at the time of winding and the condition of the subsequent tension attenuation. In general, winding is performed while reducing the tension so that the winding tension is initially high in order to prevent collapse and becomes low when winding is completed (FIG. 3). In order to stabilize the winding shape of the yarn package, the tension at the initial stage of winding and at the time of winding 120 kg are set to 60 × 10 ^{−5 to} 150 × 10 ⁻⁵ N / denier, respectively.
It is preferable to set ^{-5 to} 100 × 10 ^-5 N / denier.

In the case of producing carbon fiber using the acrylic yarn package of the present invention, the package is set on a creel in a firing step, and then the yarn is pulled out of the package, and the oxidization is performed at a low speed in an oxidizing furnace and a pre-carbonization furnace. To the furnace / carbonization furnace,
It is made into carbon fiber by firing at high temperature. This package has at least 3000 filaments, preferably 1 filament.
It is suitable for obtaining 2,000 or more carbon fibers.

[0017]

The present invention will be described more specifically with reference to the following examples.

Examples 1 to 8 and Comparative Example 1 A stock solution for spinning a 19% DMSO solution of an acrylic polymer composed of 99.6% by weight of acrylonitrile and 0.4% by weight of itaconic acid and having an intrinsic viscosity [η] of 1.80. 0.1m
DMSO 35%,
Dry-wet spinning was performed in a 5 ° C coagulation bath containing 65% water to obtain a coagulated yarn. The coagulated yarn was stretched three times in hot water while washing with water, and the remaining DMSO was washed with water until the amount became 0.01% or less in the yarn.
Dry densification was performed at 0-160 ° C. Subsequently, after being stretched by a factor of 4 in a pressurized steam, it is dried again, and four 3000 filament yarns are plied to give a single fiber fineness of 1 d, 1
Winding machine for 2,000 filament yarn with outer diameter of 145
It was wound on a core bobbin made of FRP of mm.

Various winding machines were prepared as described above, and winding with various winding amounts was attempted while changing the yarn traverse width L. At this time, the winding ratio is changed in accordance with the winding amount so that the twill angle is in the range of 8 to 12 degrees (FIG. 2).
Medium (1)), and winding was performed while the tension attenuation gradient was the curve shown in FIG. 3 (1). Table 1 shows the results. In Table 1, the swelling amount of the end face is used as a measure of the winding shape (the average value of k1 and k2 in FIG. 1).
Is measured, and the swelling amount is less than 25 mm.
Less than △ and を 30 mm or more. By increasing L, the maximum winding amount can be increased. However, if L / D is less than 0.9, the winding shape is deteriorated, and L / D is 1.4.
When it exceeded, winding of 120 kg or more could not be performed.

[0020]

[Table 1] Comparative Example 2 A yarn was wound in the same manner as in Example 6 except that the winding ratio was fixed at 7.43 ((2) in FIG. 2) and the helix angle range was 3.0 to 12.3 degrees. Table 1 shows the results of the winding shape. When winding was performed at a constant wind ratio, winding of 120 kg or more was possible, but the swelling amount of the package end face was increased and the winding shape was deteriorated.

Examples 9 to 11 A 165 kg yarn was wound in the same manner as in Example 6, except that the initial tension and the tension during winding of 120 kg, that is, the tension attenuation gradient was changed to each of the tension patterns shown in FIG. Tried. Table 1 shows the results. Initial tension and 12
By setting the tension at the time of 0 kg winding to a certain range, the winding shape became good and 165 kg winding could be performed. But 120kg
When the tension at the time of winding was excessively lowered, as shown in Example 10, at the time of winding of 125 kg, the yarn came off the guide roll of the winding machine and could not be wound.

Examples 12 to 14 A yarn was wound in the same manner as in Example 6 except that the core bobbin was changed to a paper bobbin or a bakelite, respectively, to obtain an acrylic yarn package having a winding amount of 165 kg. . When these packages and the package obtained in Example 6 were placed horizontally on a carrier for receiving and transporting both ends of the core bobbin, and placed on a truck and reciprocated on a 100 km general road, the results shown in Table 2 were obtained. Was. When the bobbin material was paper, the bobbin receiving portion was crushed or the bakelite material was chipped, but there was no problem with the FRP core bobbin without breakage.

[0023]

[Table 2]

[0024]

According to the present invention, even a yarn package in which an acrylic yarn is wound on a core bobbin with a winding amount of 120 kg or more can be formed in a good winding shape and does not fall off when unwound.

When carbon fibers are produced using the acrylic yarn package of the present invention, productivity in the firing step of carbon fibers can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a twill angle in a yarn package of the present invention, and is an axial sectional view of the yarn package.

FIG. 2 is a diagram illustrating a relationship between a winding amount and a twill angle when winding an acrylic thread around a core bobbin.

FIG. 3 is a relationship diagram (tension pattern graph) between a winding amount and a winding tension when an acrylic thread is wound on a core bobbin.

[Explanation of symbols]

 1: Acrylic yarn package 2: Core bobbin 3: Acrylic yarn d: Outer diameter of core bobbin D: Outer diameter of yarn package L: Thread traverse width k1, k2: Bend amount of end face θ: Twill angle α: Core bobbin axial direction Line perpendicular to

Claims (4)

[Claims] 1. A cylindrical package in which an acrylic yarn is wound around a core bobbin in a cylindrical shape, wherein the traverse width L of the yarn is 550 mm or more, and a ratio L between L and the outer diameter D of the cylindrical package. Acrylic yarn package characterized in that / D is in the range of 0.9 to 1.4, the winding angle is in the range of 6 to 14 degrees, and the winding amount of the yarn is 120 kg or more per package. 2. The acrylic yarn package according to claim 1, wherein the core bobbin is made of fiber reinforced plastic. 3. The acrylic yarn package according to claim 1, wherein the acrylic yarn is an acrylic yarn for carbon fibers having 3000 or more filaments. 4. When winding an acrylic yarn around a core bobbin,
By changing the winding ratio a plurality of times, the winding angle is controlled in the range of 6 to 14 degrees, and the initial tension of the yarn is 6 degrees.
The package according to claim 1 is obtained by winding at 0 × 10 ^{−5 to} 150 × 10 ⁻⁵ N / denier and winding at a tension of 120 × 10 ^{−5 to} 100 × 10 ⁻⁵ N / denier when winding up to 120 kg. A method for manufacturing an acrylic yarn package.