KR20210049790A - Acrylic thread package - Google Patents

Abstract

In order to provide an acrylic yarn package that does not cause winding collapse during transportation when an acrylic yarn having a high total fineness is wound on the core bobbin, an acrylic yarn having a total fineness of 8000 dtex or more is wound around the bobbin, and the acrylic yarn on the package An acrylic yarn package having a yarn width of 0.22 mm/1000 dtex or more and a hardness of 60 or more.

Description

Acrylic thread package

The present invention relates to a package of acrylic yarns, and to an acrylic yarn package having a good winding shape and less trouble during transportation or during transportation. Particularly, the present invention is suitable as an acrylic precursor yarn package used for producing carbon fibers.

Polyacrylonitrile-based long fibers are not only used for medical purposes, but are also used as precursors of carbon fibers in recent years, and many improved technologies have been disclosed to obtain carbon fibers having excellent performance or to increase their productivity.

The carbon fiber is a flame-resistant process in which the fiber is converted into oxidized fiber by heating and sintering the fiber in an air atmosphere at 200 to 300°C after being wound up once in the spinning process of spinning the acrylonitrile-based fiber yarn, which is its precursor. , It is obtained by going through a carbonization process of carbonizing by heating at an additional 300 to 3000°C in an inert atmosphere such as nitrogen, argon, helium, etc., and widely used as a reinforcing fiber of a composite material for aerospace, sports, and general industrial applications. Has become.

In general, carbon fibers are multifilaments composed of filaments having 1,000 or more single yarns as a single yarn unit, but the acrylic yarn used as a raw material is from the difference in production yarn speed from the firing process used as a post process, once in the spinning process. After winding up, it is generally sent to the firing process. In order to increase the productivity in the firing process, it is effective to increase the amount of acrylic yarn that can be processed at a time, but since acrylic yarn is usually wound around a core bobbin, if a large amount of yarn is wound around one bobbin, the firing process The bobbin may be stretched in the vertical direction during transport to the bobbin, or the swelling of the end faces may increase, and thus, the winding collapse, which becomes a defect in the firing step, may occur.

In the acrylic yarn package for a carbon fiber precursor, in order to obtain a good winding shape during winding, Patent Document 1 describes a technique for specifying winding conditions such as a lead angle and winding tension, but the winding collapse during transportation There is no description. In addition, for thick acrylic yarns of 33000 dtex or more, a technique for obtaining a good winding shape by taking a specific yarn width and yarn deviation ratio is described in Patent Document 2, but unless moisture is given to the yarn before winding to improve the binding properties. However, it is not possible to completely prevent the troubles at the time due to deterioration of the winding shape, and there is a problem that the winding collapse occurs even during transportation.The running cost increases due to moisture imparting and the mass increases, so it is not possible to move over long distances. What was not suitable was a problem.

In addition, in order to prevent winding collapse during transport, a technique for defining the hardness of the package in fibers having a total fineness of about tens to several hundred dtex is described in Patent Document 3 or Patent Document 4, but the total fineness exceeds 1000 dtex. It was not possible to apply it as it is to an acrylic yarn package for a carbon fiber precursor having a high fineness.

Japanese Patent Application Laid-Open No. Hei 11-263534 Japanese Patent Laid-Open No. 2002-3081 Japanese Patent Laid-Open Publication No. 51-23322 Japanese Patent Application Publication No. 2005-273106

The present invention solves the problems of the prior art, and it is an object of the present invention to provide an acrylic yarn package in which the winding collapse does not occur during transportation when an acrylic yarn having a large total fineness is wound around a core bobbin.

In order to solve this problem, the present invention employs the following means. That is, the acrylic yarn package of the present invention is a package in which an acrylic yarn having a total fineness of 8000 dtex or more is wound on a bobbin, and the yarn width of the acrylic yarn on the package is 0.22 mm/1000 dtex or more, and an acrylic yarn package having a hardness of 60 or more.

In the present invention, when an acrylic yarn having a high total fineness is wound around a core bobbin, it is possible to provide an acrylic yarn package having a good winding shape, which does not collapse even when transported to the next step.

1 is a schematic diagram showing an acrylic yarn package.
2 is a schematic diagram showing an acrylic yarn package in which warpage has occurred in the center.

The present invention is the above object, when winding an acrylic yarn of high total fineness on a core bobbin, a carbon fiber precursor acrylic thick yarn package having a good winding shape that does not collapse even during transportation was studied carefully, and the yarn width of the package And by making the hardness more than a certain amount, it was found out that these problems were solved.

The carbon fiber precursor acrylic yarn used in the present invention is composed of a so-called acrylic polymer, for example, a polymer formed by polymerizing a comonomer of preferably 90% by mass or more of acrylonitrile and less than 10% by mass of a comonomer. Examples of such comonomers include acrylic acid, methacrylic acid, itaconic acid, or their methyl ester, ethyl ester, propyl ester, butyl ester, alkali metal salt, ammonium salt, or allyl sulfonic acid, metalyl sulfonic acid, or alkali metal salts thereof. At least one type can be used.

Such acrylic polymers are obtained by using known polymerization methods such as emulsion polymerization, suspension polymerization, solution polymerization, etc., and when producing acrylic fibers from these polymers, for example, dimethylacetamide, dimethylsulfoxide A polymer solution containing a solvent selected from seeds (hereinafter referred to as DMSO), dimethylformamide, nitric acid, zinc chloride, and sodium thiocyanate aqueous solution is used as a spinning yarn, and is spun by a wet spinning method or a dry spinning method.

The spun yarn is then provided for stretching in the bath, and stretching in the bath may be performed directly on the emitting yarn, or after washing the emitting yarn once with water and removing the solvent. The stretching in such a bath is preferably stretched by about 2 to 6 times in a stretching bath of 50 to 98°C, and after stretching, an oil agent is preferably applied, and after drying and densification with a hot roller or the like, it is provided for steam stretching. , It is wound around the core bobbin to form a package.

When winding into such a package, a plurality of yarns may be wound after plying several yarns, and in order to improve the productivity of carbon fibers, it is effective to fire the multifilament yarns at once, and the total fineness of the yarns wound in the present invention is 8000 dtex. That's it. In addition, the moisture content of the yarn is preferably 3% or less in order to avoid an increase in mass during transportation. The total amount of acrylic yarn obtained by subtracting the bobbin mass and water content from the total mass of the package is preferably larger, preferably 120 kg or more, and more preferably, in order to reduce the number of acrylic yarn yarns in the firing process and improve work efficiency. Wind up so that it is more than 200kg.

In order to eliminate winding collapse during transportation, it is important to set the hardness of the bobbin end measured by a durometer to be 60 or more. When the hardness is less than 60, the package is liable to become loose, and the winding collapse during transportation and the omission of the pattern is likely to occur. In order to make the hardness 60 or more, it can be achieved by setting the tension of the thread at the time of winding to an appropriate value. In winding a large amount of yarn, it is common to gradually attenuate the tension from a large tension and wind it, but the value can take an appropriate value depending on the fineness of the yarn or the number of filaments.

In addition, in the acrylic yarn package of the present invention, it is necessary to wind up with the yarn width of the acrylic yarn on the package being 0.22 mm/1000 dtex or more. If the yarn width is less than 0.22 mm/1000 dtex, the thickness of the yarn becomes large, and a gap is created in which the yarn is shifted between adjacent yarns, and winding collapse is likely to occur during transportation. In addition, if the yarn width is greater than 0.54 mm/1000 dtex, the convergence of the yarn deteriorates, and troubles such as omission of a pattern or winding of a single yarn may occur during the firing process, so the yarn width of the acrylic yarn on the package Silver is preferably in the range of 0.22 mm to 0.54 mm/1000 dtex. The method of setting the yarn width on the package to the above range is not particularly limited, but a method of winding up a thread after passing through a group of free rollers for collecting by a certain or more is suitably used when winding the thread with a winder.

In the acrylic yarn package of the present invention, if the coefficient of static friction of the acrylic yarn is less than 0.13, even if the yarn width or hardness is controlled under specific conditions to prevent the winding collapse, end face expansion may occur during winding, so it is suitable. It is preferable to make the static friction coefficient 0.13 or more by providing a kind and a positive oil agent.

In addition, in the acrylic yarn package of the present invention, it is preferable to set the yarn displacement ratio to 15 to 59%, and to set the lead angle on the package to a range of 6 to 14°. The yarn shift ratio is the ratio of the yarn shift amount S to the yarn width T in two threads passing through the nearest part on the package in parallel. That is, this thread shift ratio is calculated|required by (S/T) x 100 shown in FIG. If this is conceptually explained using FIG. 1, the acrylic thread 4 is a thread passing through the closest point on the acrylic thread package 1 in parallel with respect to the acrylic thread 3, the acrylic thread 3 and the acrylic thread. It is the ratio of the thread misalignment amount S of the thread 4 to the thread width T. In addition, the thread width T and the thread displacement amount S are values measured by the method mentioned later, respectively.

In addition, the lead angle is an angle formed by a straight line perpendicular to the axis of the core bobbin 2 (a line α perpendicular to the axis direction of the core bobbin) and the direction of the wound acrylic thread 4, as shown in FIG. (θ).

The yarn shift ratio and the lead angle can be controlled by setting the winding machine spindle rotation speed per thread traverse, so-called winding ratio, to an appropriate value. If the winding ratio is an integer, the actual path is completely the same before and after one traverse, so by setting the fractional part of the winding ratio to an appropriate value, the actual length before and after one traverse can be shifted, and the thread shift ratio can be controlled. In addition, the lead angle can be controlled by setting the size of the entire winding ratio including the integer portion to an appropriate value. Regarding the yarn displacement ratio, if it is less than 15%, a package with large undulations will be obtained, and even if the winding tension is increased, the hardness may be inferior, and winding collapse is likely to occur during transportation. In addition, when the yarn displacement ratio is greater than 59%, the inner layer yarn and the outer layer contact surface become smaller, so that the inner layer yarn slides and is extruded outward due to the pressure of the outer layer yarn during winding, and the end face expands. Therefore, by setting the yarn shift ratio in the range of 15% to 59%, both the hardness and the shape of the end face can be made good numerical values, which is preferable.

In addition, if the lead angle is less than 6°, omission of the pattern is likely to occur, and if the lead angle is greater than 14°, the end face expansion increases, so the lead angle is preferably within the range of 6 to 14°. Do. When winding with a constant winding ratio, the lead angle decreases linearly as the diameter of the package wound around the core bobbin increases. By changing the winding ratio during winding according to the thread winding amount, the lead angle is maintained within a certain range. I can wind it up while doing it. For example, by making the spindle drive and the traverse drive independent, and after detecting the spindle rotational speed, calculating the set wind ratio, and controlling the traverse drive rotational speed, the wind ratio is adjusted according to the amount of winding in the winding process. It can be set freely.

Example

Hereinafter, the present invention will be described in detail by showing examples and comparative examples. The measurement methods used in Examples and Comparative Examples are described next.

<Total fineness>

A sample thread of 20 m was collected from the package to be measured, and the total fineness was calculated by a method according to JIS L1013:2010.

<Standing friction coefficient>

1.5 m of sample yarn was collected from the package to be measured, and wound around the package after the collection. At this time, it was wound around the center of the package along the circumferential surface of the package. After winding the sample thread so that the contact angle with the package was 540°, weights of 150 g were attached to both ends of the sample thread. Thereafter, the mass of the weight on the one end side of the yarn was increased, and the mass when the yarn started to slide on the separate roll was measured, and the mass was determined from the following equation.

Static friction coefficient (µs) = 3/π×Ln(T1/150)

π: circumference ratio

T1: The mass of the weight when it starts to slide (g).

<thread width>

The yarn width of the acrylic yarn on the package was measured using a knuckle and a total of 5 points inside the package 2 cm from both ends (hereinafter referred to as both ends), the center, and between both ends and the center, and the value divided by the total fineness is called the yarn width. did.

<Ratio of thread deviation>

With respect to the two threads passing through the closest point on the package in parallel, the amount of thread misalignment (S) shown in FIG. 1 was measured using a knuckle for a total of 5 points between both ends, the center, and both ends and the center of the package, and the average value thereof The value divided by the actual width was referred to as the actual deviation ratio.

<Lead angle range>

While doing the rolled-up package, a straight line α perpendicular to the axial direction of the core bobbin 2 shown in FIG. 1 and the direction of the wound thread 4 at intervals of 10 kg until all the threads disappear. The formed angle θ was measured at the center of the package, and the range of the measured value was referred to as the lead angle range.

<hardness>

Using Kobunshikeki's Hardness Tester "Type C" (for Cellular Rubber & Yarn Package), measure two places inside 2 cm from both ends of the package, and measure the average value of the yarn package. It was called hardness.

<Cold collapse during transport>

The acrylic yarn package was passed through a bogie equipped with a spindle, and a transport vibration test according to JIS Z0232:2004 was carried out once for one acrylic yarn package, and the presence or absence of winding collapse was determined by the following two levels.

(Circle): There was no increase of 5.0 mm or more in the end surface expansion, and 10 mm or more increase of the warpage.

X: There was an increase of 5.0 mm or more in the expansion of the end face and an increase of 10 mm or more in the warpage.

In addition, from the straight line 5 connecting both ends of the upper part of the package shown in FIG. 2, the distance U of the farthest point from the curve 6 along the upper part of the package was measured, and was called the warp U.

<Expansion of the end surface>

With respect to the thread traverse width (L) at the outermost surface of the package shown in FIG. 1, the end surface expansion amounts (k1, k2), which are the heights of the point at which the side of the package is expanded most out, are measured from both sides of the package, and The average value was called end face expansion.

<Happy City Trouble>

When the package was applied to the krill in its entirety, the occurrence of no omission of the pattern or the winding of the single yarn was indicated as ◯, and the occurrence of the result was indicated as x.

(Example 1)

Using a 19% DMSO solution of an acrylic polymer having an intrinsic viscosity [η] of 1.80 containing 99.6% by mass of acrylonitrile and 0.4% by mass of itaconic acid as a spinning dope, using a 6,000-pore orifice, 30% of DMSO and water Dry-wet spinning was performed in a coagulation bath containing 70% at 8°C to obtain coagulated yarn. The coagulated yarn was stretched 2.8 times in hot water while washing with water, and after washing with water until the remaining DMSO was 0.01% or less in the yarn, a silicone oil agent was applied, and dry densification was performed at 150 to 160°C. Subsequently, after applying 4.3 times of stretching in pressurized steam, it was dried again. Two 6000 filament yarns are laminated, and 12000 filaments, a total fineness of 13,300 dtex yarns are wound into an FRP core bobbin with an outer diameter of 145 mm, with the yarn width, yarn shift ratio, and lead angle range shown in Table 1. It wound up so that the total amount of the acrylic yarn obtained by subtracting the bobbin mass and water amount from the mass became 120 kg. In addition, the moisture content was obtained by collecting about 12 m of the thread to be wound up in advance, measuring the moisture content by a method in accordance with JIS L1013:2010, and multiplying the amount of thread wound up.

As shown in Table 1, the result was a good package without winding collapse during transportation.

(Examples 2 to 5, Comparative Examples 1 to 4)

In the same manner as in Example 1, except that the total amount of acrylic yarn obtained by subtracting the bobbin mass and water content from the total mass of the package was 240 kg, the yarn width at the time of winding, the wind ratio or tension of the winder were changed, and the yarn width shown in Table 1 , The yarn deviation ratio, and the lead angle range.

As shown in Table 1, for Examples 2 to 5, it was a good package without winding collapse during transportation, but for Example 4, the yarn displacement ratio at the time of winding was as large as 60% or more, and the inner layer yarn and the outer layer yarn were Since the contact surface becomes small, the outer layer thread presses the inner layer thread during winding, and the inner layer thread slides and is extruded outward, resulting in a package having a large end surface expansion. In addition, in Example 5, the yarn width was 0.55 mm/1000 dtex or more, and the thread convergence was poor, and therefore, in the firing step, omission of patterns and winding of single yarn occurred. In Comparative Examples 1 to 3, compared with Example 2, the hardness was less than 60, and winding collapse occurred during transportation. In Comparative Example 4, compared with Example 2, the yarn width was less than 0.22 mm/1000 dtex, and winding collapse occurred during transportation.

(Examples 6 and 7)

It carried out similarly to Example 2, except having adjusted the adhesion amount of the oil agent to change the static friction coefficient of the thread, and wound up at the yarn width and the yarn displacement ratio shown in Table 1. As shown in Table 1, the result was a good package without winding collapse during transportation. In Example 6, the static friction coefficient was as low as less than 0.13, and the lateral slip of the yarn occurred during winding, resulting in a package having a large end surface expansion.

(Example 8)

In the same manner as in Example 2 except that four 6000 filament threads were plied together, a thread having 24,000 filaments and a total fineness of 26600 dtex was wound up at the yarn width and yarn displacement ratio shown in Table 1.

As shown in Table 1, the result was a good package without winding collapse during transportation.

(Example 9)

In the same manner as in Example 8, except that the draw ratio in the pressurized steam was 3.9 times, 24,000 filaments and a total fineness of 29,100 dtex were wound up at the yarn width and yarn displacement ratio shown in Table 1.

As shown in Table 1, the result was a good package without winding collapse during transportation.

(Example 10)

In the same manner as in Example 2, except that six 6000 filament yarns with a single yarn fineness of 0.74 dtex were plied together, 36000 filaments and a total fineness of 26,600 dtex were wound up at the yarn width and yarn displacement ratio shown in Table 1.

As shown in Table 1, the result was a good package without winding collapse during transportation.

1: Acrylic thread package
2: core bobbin
3: Acrylic thread
4: acrylic thread
5: Straight line connecting both ends of the top of the package
6: Curve riding the top of the package
L: thread traverse width
k1, k2: amount of end surface expansion
S: thread misalignment
T: thread width
U: bending
θ: lead angle
α: A line perpendicular to the axis of the core bobbin

Claims (4)

An acrylic yarn package in which an acrylic yarn having a total fineness of 8000 dtex or more is wound on a bobbin, and the yarn width of the acrylic yarn on the package is 0.22 mm/1000 dtex or more, and a hardness of 60 or more. The acrylic yarn package according to claim 1, wherein the total amount of the acrylic yarn is 120 kg or more. The acrylic yarn package according to claim 1 or 2, wherein the acrylic yarn has a static friction coefficient of 0.13 or more. The acrylic yarn package according to any one of claims 1 to 3, wherein the acrylic yarn on the package has a yarn width of 0.22 to 0.54 mm/1000 dtex, a yarn displacement ratio of 15 to 59%, and a lead angle of 6 to 14°. .

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