阅读说明：本技术 丙烯酸系纱条卷装 (Acrylic yarn package ) 是由 大岛郁人 川本贵史 村上哲也 于 2019-08-20 设计创作，主要内容包括：为了提供在将总纤度大的丙烯酸系纱条卷绕于芯筒时在搬运时不会发生卷崩散的丙烯酸系纱条卷装,该丙烯酸系纱条卷装为将总纤度为8000dtex以上的丙烯酸系纱条卷绕于筒管而成的卷装,卷装上的丙烯酸系纱条的纱宽为0.22mm/1000dtex以上、且丙烯酸系纱条卷装的硬度为60以上。(To provide an acrylic yarn package in which an acrylic yarn having a large total fineness is wound around a bobbin, and in which the acrylic yarn is not broken during transportation, the acrylic yarn package is formed by winding an acrylic yarn having a total fineness of 8000dtex or more around the bobbin, the yarn width of the acrylic yarn in the package is 0.22mm/1000dtex or more, and the hardness of the acrylic yarn package is 60 or more.)

1. An acrylic yarn package in which an acrylic yarn having a total fineness of 8000dtex or more is wound around a bobbin, wherein the yarn width of the acrylic yarn in the package is 0.22mm/1000dtex or more, and the hardness of the acrylic yarn package is 60 or more.

2. The package of acrylic yarn according to claim 1, wherein the total amount of acrylic yarn is 120kg or more.

3. The acrylic sliver package according to claim 1 or 2, wherein the static friction coefficient of the acrylic sliver is 0.13 or more.

4. The acrylic yarn package according to any one of claims 1 to 3, wherein the yarn width of the acrylic yarn on the package is 0.22 to 0.54mm/1000dtex, the yarn deviation ratio is 15 to 59%, and the package crossing angle is 6 to 14 °.

Technical Field

The present invention relates to an acrylic yarn package having a good winding shape and less troubles (bobbin) during transportation and unwinding. In particular, the present invention is suitable as a package of an acrylic precursor yarn for use in carbon fiber production.

Background

Polyacrylonitrile-based long fibers are used not only for clothing but also as precursors of carbon fibers (precursor) in recent years, and a number of improvement techniques have been disclosed for obtaining carbon fibers having excellent performance and improving productivity thereof.

Carbon fibers are obtained by once winding a yarn in a yarn-making step of spinning an acrylic fiber sliver which is a carbon fiber precursor, and then feeding the wound yarn to a burning step, followed by a flame-resistant step (in which the fiber is heated and burned in an air atmosphere at 200 to 300 ℃ to convert the fiber into an oxidized fiber), and a carbonization step (in which the fiber is further heated to 300 to 3000 ℃ in an inert gas atmosphere such as nitrogen/argon/helium to carbonize the fiber); carbon fibers are widely used as reinforcing fibers for composite materials in aerospace applications, sports applications, general industrial applications, and the like.

In the case of carbon fibers, a multifilament yarn composed of filaments having 1000 or more filaments is usually used as one yarn unit, but an acrylic yarn as a raw material is usually wound once in a yarn-making step and then sent to a firing step due to a difference in yarn-producing speed from that in the firing step which is a subsequent step. In order to improve productivity in the firing step, it is effective to increase the amount of acrylic yarn that can be handled at a time, but since acrylic yarn is usually wound around a core bobbin (core bobbin), if a large amount of yarn is wound around one bobbin (bobbin), the bobbin becomes vertical in the vertical direction during conveyance to the firing step, and the end surface bulges greatly, and roll breakage (japanese patent: coil breakage れ) such as unwinding failure in the firing step may occur.

Patent document 1 discloses a technique for defining winding conditions such as a winding crossing angle and a winding tension in an acrylic sliver package for a carbon fiber precursor in order to obtain a good winding shape during winding, but does not describe roll collapse during transportation. Further, a technique of obtaining a good roll shape by using a specific yarn width and a specific yarn deviation ratio for a coarse acrylic yarn of 33000dtex or more is described in patent document 2, but there are problems that deterioration of the roll shape and a trouble at the time of unwinding cannot be completely prevented unless moisture is applied to the yarn before winding to improve the bundling property, roll collapse occurs even at the time of transportation, and further, the problem is that the yarn is not suitable for long-distance movement due to an increase in running cost (running cost) and an increase in mass caused by the application of moisture.

Further, in order to prevent the collapse of the package during the transportation, a technique for defining the package hardness of the fiber having a total fineness of about several tens to several hundreds dtex is described in patent documents 3 and 4, but this technique cannot be directly applied to an acrylic yarn package for a carbon fiber precursor having a large total fineness of more than 1000 dtex.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. Hei 11-263534

Patent document 2: japanese patent laid-open publication No. 2002-3081

Patent document 3: japanese patent laid-open No. Sho 51-23322

Patent document 4: japanese patent laid-open No. 2005-273106.

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide an acrylic yarn package in which, when an acrylic yarn having a large total fineness is wound around a core, the acrylic yarn package is not broken during transportation.

Means for solving the problems

The present invention adopts the following means to solve the above problems. That is, the acrylic yarn package of the present invention is a package in which an acrylic yarn having a total fineness of 8000dtex or more is wound around a bobbin, the yarn width of the acrylic yarn in the package is 0.22mm/1000dtex or more, and the hardness of the acrylic yarn package is 60 or more.

Effects of the invention

The present invention can provide an acrylic yarn package having a good winding shape that does not collapse when being transported to the next step when an acrylic yarn having a high total fineness is wound around a core.

Drawings

FIG. 1 is a schematic view showing an acrylic yarn package.

FIG. 2 is a schematic view showing an acrylic sliver package warped at the center.

Detailed Description

The present inventors have conducted intensive studies on the above-mentioned problems, that is, a package of a carbon fiber precursor acrylic coarse yarn having a good winding shape which does not collapse even when being transported when an acrylic yarn having a high total fineness is wound around a core tube, and have found that the above-mentioned problems can be solved by setting the yarn width and hardness of the package to be constant or more.

The carbon fiber precursor acrylic yarn used in the present invention is a yarn made of a so-called acrylic polymer (for example, a polymer obtained by polymerizing 90 mass% or more of acrylonitrile and less than 10 mass% of a comonomer is preferable). As the comonomer, at least one selected from acrylic acid, methacrylic acid, itaconic acid or methyl, ethyl, propyl, butyl, alkali metal, ammonium salts thereof, or allyl sulfonic acid, methallyl sulfonic acid, or alkali metal salts thereof, and the like can be used.

The acrylic polymer is obtained by a known polymerization method (for example, a polymerization method such as emulsion polymerization, suspension polymerization, or solution polymerization), and when an acrylic fiber is produced from these polymers, a polymer solution containing a solvent selected from, for example, dimethylacetamide, dimethylsulfoxide (hereinafter, referred to as DMSO), dimethylformamide, nitric acid, zinc chloride, and an aqueous solution of sodium thiocyanate is spun as a spinning raw yarn by a wet spinning method or a dry spinning method.

The spun yarn may be directly drawn in a bath, or may be subjected to a primary water washing to remove the solvent. The above-mentioned in-bath stretching is preferably carried out in a stretching bath at 50 to 98 ℃ by a factor of about 2 to 6, and after stretching, it is preferably carried out by applying an oil agent, drying and densifying with a hot roll or the like, then it is subjected to steam stretching, and then it is wound around a core tube to form a package.

In the winding into the package, the plurality of yarns may be wound after being combined several times, and it is effective to burn the plurality of filament yarns at once in order to improve the productivity of the carbon fiber, so that the total fineness of the wound yarns in the present invention is 8000dtex or more. In order to avoid an increase in mass during transportation, the moisture content of the sliver is preferably 3% or less. In order to reduce the number of times the acrylic yarn is set up in the firing step and to make the operation efficient, the total amount of the acrylic yarn obtained by subtracting the bobbin mass and the moisture amount from the mass of the whole package is preferably large, and is preferably wound so as to be 120kg or more, more preferably 200kg or more.

In order to eliminate the coil collapse during transportation, it is important to set the hardness of the end of the bobbin measured by a hardness meter to 60 or more. If the hardness is less than 60, the package tends to be loosened, and collapse and jump during unwinding during transportation tend to occur. The hardness of 60 or more can be achieved by setting the tension of the yarn at the time of winding to an appropriate value. In winding a large number of strands, the tension is generally gradually decreased from a high tension to wind the strands, but the numerical value may be an appropriate value depending on the fineness of the strands and the number of filaments.

In the acrylic yarn package of the present invention, it is necessary to wind the acrylic yarn package so that the yarn width of the acrylic yarn is 0.22mm/1000dtex or more. If the yarn width is less than 0.22mm/1000dtex, the thickness of the yarn becomes large, and a gap in which the yarn is deviated from an adjacent yarn is generated, and the yarn is likely to be wound and broken during transportation. Further, when the yarn width is more than 0.54mm/1000dtex, the yarn width of the acrylic yarn to be wound is preferably in the range of 0.22mm to 0.54mm/1000dtex, because the yarn collecting property of the yarn becomes poor, and troubles such as skipping ( drop ち) and winding of a single yarn may occur during unwinding in the firing step. The method of setting the yarn width of the package within the above range is not particularly limited, and when the yarn is wound by the winder, a method of winding after passing through a fixed or more free roller group for bundling is suitably used.

In the acrylic sliver package of the present invention, when the static friction coefficient of the acrylic sliver is less than 0.13, the static friction coefficient is preferably set to 0.13 or more by applying an appropriate kind and amount of oil agent, because the end surface bulge may occur during winding even if the yarn width and hardness are controlled to specific conditions to prevent the collapse of the package.

In the acrylic yarn package of the present invention, it is preferable that the yarn deviation ratio is 15 to 59% and the package cross angle is 6 to 14 °. The sliver displacement ratio is a ratio of the sliver displacement amount S to the yarn width T of two slivers passing in parallel at the closest point in the package. That is, this sliver displacement ratio is a value obtained by (S/T) × 100 shown in fig. 1. In the conceptual explanation of the acrylic yarn 4 using fig. 1, the acrylic yarn 4 passes through the acrylic yarn package 1 in parallel at the closest point to the acrylic yarn 3, and the ratio of the yarn width T to the yarn width S of the acrylic yarn 3 and the acrylic yarn 4 is the yarn offset ratio. The yarn width T and the sliver displacement S are values measured by the methods described later.

The winding cross angle is an angle (θ) formed by a straight line perpendicular to the axis of the core barrel 2 (a line α perpendicular to the axial direction of the core barrel) and the direction of the wound acrylic yarn 4, as shown in fig. 1.

The yarn deviation ratio and the package crossing angle can be controlled by setting the rotation speed of the main shaft of the winder in each 1 yarn traverse (the yarn トラバース), so-called winding ratio, to appropriate values. If the winding ratio is an integer, the yarn passes through exactly the same yarn path before and after 1 traverse, and therefore, by setting the fractional part of the winding ratio to an appropriate value, the yarn path before and after 1 traverse can be shifted, and the sliver displacement ratio can be controlled. Further, the winding crossing angle can be controlled by setting the size of the entire winding ratio including the integer part to an appropriate value. If the sliver displacement ratio is less than 15%, the package will have large undulations, and the hardness will be reduced even if the winding tension is increased, and the package will easily collapse during transportation. When the sliver displacement ratio is more than 59%, the surface where the inner layer yarn and the outer layer yarn contact each other becomes small, and therefore the inner layer yarn slides and is pushed out to the outside by being pressed by the outer layer yarn during winding, and the end surface bulges. Therefore, it is preferable that the sliver displacement ratio is in the range of 15% to 59%, since both the hardness and the end face shape can be made good.

In addition, if the winding intersection angle is less than 6 °, jumping at unwinding is likely to occur, and if the winding intersection angle is greater than 14 °, the end surface bulge becomes large, so the winding intersection angle is preferably in the range of 6 to 14 °. When winding is performed at a constant winding ratio, the winding crossing angle linearly decreases as the diameter of the package wound up to the core increases, and therefore, by changing the winding ratio during winding in accordance with the amount of yarn wound, winding can be performed while keeping the winding crossing angle within a constant range. For example, by providing a mechanism in which the main shaft drive and the traverse drive are independent, and the traverse drive rotational speed is controlled after the main shaft rotational speed is detected and calculated so as to be the set winding ratio, the winding ratio can be freely set in accordance with the winding amount during the winding process.

Examples

The present invention will be described in detail below with reference to examples and comparative examples. The measurement methods used in examples and comparative examples will be described below.

< Total fineness >

A sample sliver 20m was collected from a package as a measurement target, and the sample sliver was measured according to JIS L1013: 2010 Total fineness was determined.

< coefficient of static friction >

A sample sliver was collected by 1.5m from a package to be measured, and wound up into the collected package. At this time, the winding is performed along the circumferential surface of the package to the center of the package. After winding the sample yarn so that the contact angle with the package became 540 °, 150g weights were attached to both ends of the sample yarn. Then, the mass of the weight on one end side of the yarn was increased, and the mass when the yarn started to slide on the separation roller was measured and obtained by the following equation.

Coefficient of static friction (μ s) ═ 3/π × Ln (T1/150)

Pi: circumferential ratio

T1: mass (g) of weight at the start of sliding.

Width of yarn

The yarn width of the acrylic yarn on the package was measured at positions 2cm inside from both ends of the package (hereinafter referred to as both ends), at the center, and at 5 positions in total between both ends and the center using a caliper, and the value obtained by dividing the yarn width by the total fineness was defined as the yarn width.

< sliver offset ratio >

For two slivers passing in parallel at the closest positions on the package, the sliver displacement amount (S) shown in fig. 1 was measured at 5 positions in total of the two ends, the center, and the distance between the two ends and the center of the package using a vernier caliper, and the average value thereof was divided by the yarn width to obtain a sliver displacement ratio.

< cross included angle range of winding machine >

The angle (θ) formed by the straight line (α) perpendicular to the axial direction of the core barrel 2 shown in fig. 1 and the direction of the wound yarn 4 is measured at every 10kg at the package center while unwinding the wound package until no yarn is present, and the range of the measured values is defined as the range of the winding intersection angle.

Hardness

The hardness of the Yarn Package was measured at 2 points 2cm inside from both ends of the Package using a "Type C" hardness tester (HARDNESS TESTER, manufactured by Polymer Meter Co., Ltd.) (for foamed Rubber and Yarn Package (Cellular Rubber & Yarn Package)), and the average value was determined.

< roll collapse and Dispersion during transportation >

An acrylic yarn package was passed through a carriage with a spindle (spindle), and 1 acrylic yarn package was subjected to 1-time processing in accordance with JIS Z0232: in the transport vibration test of 2004, the presence or absence of roll collapse was determined by the following 2 criteria.

O: the end surface bulge is not increased by more than 5.0mm, and the warpage is not increased by more than 10 mm.

X: the end surface bulge is increased by more than 5.0mm, and the warpage is increased by more than 10 mm.

The warp U is measured as a distance (U) from a straight line 5 connecting both ends of the upper portion of the package shown in fig. 2 to a farthest point along a curve 6 of the upper portion of the package.

< end face bulge >

The end swell amounts (k1, k2) which are the heights of the points where the side surfaces of the package swell outward most with respect to the traverse width (L) of the yarn on the outermost surface of the package shown in fig. 1 are measured from both side surfaces of the package, respectively, and the average value thereof is taken as the end swell.

< unwell condition when relieving relaxation >

When the package was mounted on a creel and unwound, the occurrence of skipping or single yarn winding was evaluated as "o" and the occurrence of skipping or single yarn winding was evaluated as "x".

(example 1)

A 19% DMSO solution of an acrylic polymer having an intrinsic viscosity [. eta. ] of 1.80, containing 99.6 mass% of acrylonitrile and 0.4 mass% of itaconic acid was used as a spinning stock solution, and dry-wet spinning was performed in a coagulation bath at 8 ℃ containing 30% of DMSO and 70% of water using a spinneret having a hole number of 6000, to obtain a coagulated yarn. The coagulated yarn is subjected to water washing and hot water drawing to 2.8 times, further water washing is performed until the content of DMSO remaining in the yarn becomes 0.01% or less, and then a silicone oil is added thereto, followed by drying and densification at 150 to 160 ℃. Subsequently, the resultant was subjected to 4.3-fold stretching in pressurized steam and then dried again. 2 strands of 6000 filaments were combined, and a strand of 12000 filaments and a total fineness of 13300dtex was wound on an FRP core bobbin having an outer diameter of 145mm by a winder so that the total amount of acrylic strands obtained by subtracting the bobbin mass and the water content from the mass of the whole package became 120kg in the yarn width, the strand displacement ratio, and the winding cross angle range shown in Table 1. The moisture content was measured by collecting about 12m in advance from a sliver to be wound and using a method according to JIS L1013: 2010, the moisture content is measured and multiplied by the amount of the wound yarn.

As a result, as shown in table 1, the package was good without breaking during transportation.

(examples 2 to 5, comparative examples 1 to 4)

The operation was carried out in the same manner as in example 1 except that the total amount of the acrylic yarn obtained by subtracting the bobbin mass and the water content from the mass of the entire package was 240kg, and the yarn width at the time of winding, the winding ratio of the winder, and the tension were changed to wind the yarn width, the yarn offset ratio, and the winding cross angle range shown in table 1.

As a result, as shown in table 1, in examples 2 to 5, in order to obtain a good package without collapse of the package during transportation, in example 4, the sliver displacement ratio during winding was as large as 60% or more, and the surface where the inner yarn and the outer yarn were in contact with each other was small, so that the outer yarn pressed against the inner yarn during winding and the inner yarn slid and pushed out to the outside, thereby obtaining a package with a large end face bulge. In example 5, since the yarn width was as large as 0.55mm/1000dtex or more and the drawdown property of the yarn was poor, the yarn was jumped and the single yarn was entangled at the unwinding in the calcination step. In comparative examples 1 to 3, the hardness was less than 60 and the roll was broken during transportation, as compared with example 2. In comparative example 4, the yarn width was less than 0.22mm/1000dtex, and the yarn was bulky during conveyance, as compared with example 2.

(examples 6 and 7)

The operation was carried out in the same manner as in example 2 except that the amount of the oil agent adhered was adjusted to change the static friction coefficient of the yarn, and the yarn was wound at the yarn width and the yarn skew ratio shown in table 1. The results are shown in table 1, which shows a good package without breaking during transportation. In example 6, the static friction coefficient was as low as less than 0.13, and the yarn slipped in the transverse direction during winding, resulting in a package with a large end surface bulge.

(example 8)

A yarn sliver of 24000 filaments and a total fineness of 26600dtex was wound at a yarn width and a yarn sliver displacement ratio shown in table 1 in the same manner as in example 2, except that 4 pieces of 6000 filament yarn slivers were combined.

As a result, as shown in table 1, the package was a good package without the collapse of the package during transportation.

(example 9)

A yarn of 24000 filaments and a total fineness of 29100dtex was wound at a yarn width and a yarn skew ratio shown in table 1 in the same manner as in example 8, except that the draw ratio in the pressurized steam was 3.9 times.

As a result, as shown in table 1, the package was good without breaking during transportation.

(example 10)

The same operation as in example 2 was carried out except that a 6000-filament yarn having a single yarn fineness of 0.74dtex was doubled by 6, and a yarn of 36000 filaments and a total fineness of 26600dtex was wound at the yarn width and the yarn offset ratio shown in table 1.

As a result, as shown in table 1, the package was good without breaking during transportation.

[ Table 1]

Description of the reference numerals

1: acrylic yarn package

2: core tube

3: acrylic yarn

4: acrylic yarn

5: straight line connecting both ends of upper part of package

6: curve along the upper part of the package

L: transverse width of yarn

k1, k 2: end face bulge

S: offset of sliver

T: width of yarn

U: warp of

θ: intersection included angle of winding

α: line perpendicular to axial direction of core barrel