WO2018117123A1

WO2018117123A1 - Wound package of polyurethane elastic filament

Info

Publication number: WO2018117123A1
Application number: PCT/JP2017/045602
Authority: WO
Inventors: 後藤　英之
Original assignee: 旭化成株式会社
Priority date: 2016-12-19
Filing date: 2017-12-19
Publication date: 2018-06-28
Also published as: JP2020029311A; CN110088021A; CN110088021B

Abstract

Provided is a wound package of polyurethane elastic filament, wherein the quantity of wound filament of the wound package of polyurethane elastic filament is 4.50-9.00 kg, the ratio (T1/W1) of the thickness of the winding (T1) at the center of the wound package and the winding width (W1) of the outermost layer is 0.40-0.80, the ratio (W1/W2) of the winding width (W1) of the outermost layer and the winding width (W2) of the innermost layer is 0.75-1.00, and the ratio (T1/T2) of the winding thickness (T1) at the center and the winding thickness (T2) at the edge is 0.85-1.02.

Description

Polyurethane elastic thread body

The present invention relates to a polyurethane elastic yarn body.

Polyurethane elastic yarns have excellent elastic properties and are used in various products that require stretchability and fit, such as innerwear, stockings, compression wear, and diapers. The polyurethane elastic yarn is generally used in the production process of the product as described above in the form of a polyurethane elastic bobbin (generally also referred to as “cheese”) wound on a paper or resin tube.

For example, Patent Document 1 discloses that “an elastic yarn wound body having a yarn winding amount of 1.5 kg or more and a ratio B / A of a winding width A to a winding thickness B of 0.4 or more”. Are listed.

Patent Document 2 states that “an elastic bobbin wound around a tapered bobbin while traversing an elastic yarn, and the average unwinding resistance value of the elastic yarn from the elastic bobbin is 3.2. Describes an elastic yarn string characterized by a weight of ˜3.4 g ”.

Japanese Patent Laid-Open No. 01-226669 JP 2004-142944 A

In the manufacturing process of inner, stockings, compression wear, diapers, etc., when the polyurethane elastic bobbin is used continuously, the polyurethane elastic yarn thread body must be replaced (hereinafter also referred to as “ball change”). The frequency increases as the amount of winding of the kite body decreases. In recent years, especially in the manufacturing process of diapers, in order to reduce the number of ball replacements, so-called “mass winding”, in which the amount of winding of the polyurethane elastic thread body is increased. However, since the winding thickness of the thread body with a large amount of thread winding becomes thick, the yarn is detached at both ends of the thread body, a phenomenon called “twisting”, and the winding thickness at both ends of the thread body excessively increases. As a result, the unwinding stress increases when the thread body is fixed and the elastic thread is unwound, so-called `` ears '', and the thread is pushed out in the winding width direction by the tightening stress, so-called `` A phenomenon called “belly bulging” or the like occurred, and it was difficult to maintain the shape of the wound body. Ear standing, twilling, and belly swelling are not preferable because they lead to thread breakage in the manufacturing process.

For example, with an elastic thread body as described in Patent Document 1, a thread body can be provided in a good shape when the thread winding amount is less than 4.5 kg, but the shape retention is good when the thread winding amount is 4.5 kg or more. However, it was found that twilling may occur.

In addition, since the elastic thread wound body as described in Patent Document 2 is wound around a tapered bobbin, the wound body is placed on the drive roller in the product manufacturing process to unwind and remove the thread at a high speed. It turns out that it is difficult to do positive settlement.

In view of the above-described problems, the present invention can reduce the shape defect of the thread body such as twill, ears, and belly bulge even in a large volume of 4.5 kg or more. An object of the present invention is to provide a polyurethane elastic yarn body with few yarn breaks due to defects.

The present invention is as follows.
[1] The amount of winding of the polyurethane elastic yarn wound body from which the polyurethane elastic yarn has been wound is 4.50 kg or more and 9.00 kg or less, and the winding thickness (T1) of the center portion of the wound yarn body and the winding width of the outermost layer The ratio (T1 / W1) to (W1) is 0.40 or more and 0.80 or less, and the ratio (W1 / W2) between the outermost layer winding width (W1) and the innermost layer winding width (W2) is 0.75 or more and 1.00 or less, and the ratio (T1 / T2) of the winding thickness (T1) of the center portion and the winding thickness (T2) of the end portion of the thread body is 0.85 or more and 1.02. A polyurethane elastic thread body characterized by the following:
[2] The ratio (W0 / W1) of the winding width (W0) of the thread body within 100 m from the start of winding of the polyurethane elastic thread to the winding width (W1) of the thread body of the outermost layer is 0. The polyurethane elastic yarn string according to [1], which is 30 or more and 0.80 or less.
[3] Within 500 m from the start of winding of the polyurethane elastic yarn, the winding amount of the yarn wound at a winding width in which the ratio to the winding width (W1) of the outermost layer is 0.30 or more and 0.80 or less is The polyurethane elastic yarn string according to [2], which is 0.20 g or more.
[4] The polyurethane elastic yarn body according to any one of [1] to [3], wherein the polyurethane elastic yarn has a twill angle of greater than 0 degrees and less than or equal to 30 degrees.
[5] The polyurethane elastic yarn string according to any one of [1] to [4], wherein the elongation percentage of the polyurethane elastic yarn is 0.01% or more and 10% or less.

The polyurethane elastic yarn thread body of the present invention has the above-described configuration, so that even if it is a large volume of 4.50 kg or more, it is possible to reduce the shape defect of the thread body such as twill and ears. It is possible to provide a polyurethane elastic yarn body that has few yarn breaks due to defective shape of the yarn body.

It is a schematic diagram of the polyurethane elastic thread body of this embodiment. It is sectional drawing of the polyurethane elastic yarn body of this embodiment.

Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the following embodiment, and can be implemented with various modifications within the scope of the gist.

<Polyurethane elastic thread body>
The polyurethane elastic thread body of the present embodiment is a polyurethane elastic thread body that has been spun off from a polyurethane elastic thread, and the amount of winding is not less than 4.50 kg and not more than 9.00 kg. The ratio (T1 / W1) of the winding thickness (T1) to the outermost layer winding width (W1) is 0.40 or more and 0.80 or less, and the outermost layer winding width (W1) and the innermost layer winding width (W2). ) (W1 / W2) is not less than 0.75 and not more than 1.00, and the ratio (T1 / T2) of the central portion thickness (T1) to the end portion thickness (T2) is 0.85. It is 1.02 or less.

The polyurethane elastic yarn string according to the present embodiment has the above-described configuration, thereby reducing the shape defect of the string, such as twill, ears, and belly bulging, even with a large volume of 4.5 kg or more. The thread breakage due to the poor shape of the thread body can be reduced. Therefore, the polyurethane elastic yarn string of this embodiment is suitable for continuous use of polyurethane elastic yarns in the production process of various products such as inner, stockings, compression wear, and diapers. For example, the production process of diapers Is suitable for continuous use of polyurethane elastic yarns.

In the present embodiment, the polyurethane constituting the polyurethane elastic yarn is not particularly limited as long as it has a structure polymerized from, for example, diisocyanate, polymer polyol, diol, and diamine. Further, the polymerization method is not particularly limited. The polyurethane may be, for example, a polyurethane polymerized from a diisocyanate, a polymer polyol, and a low molecular weight diamine as a chain extender (also referred to as “polyurethane urea”), and may be a diisocyanate, a polymer polyol, and a chain extender. Polyurethane (also referred to as “polyurethane urethane”) polymerized from a low molecular weight diol as an agent may be used. For example, in the manufacturing process of a diaper, a high-temperature adhesive may be applied to an elastic yarn. From the viewpoint of preventing deterioration of the polyurethane elastic yarn and preventing yarn breakage by applying a high-temperature adhesive, polyurethane elastic yarn is polyurethane. It is preferable to contain urea.

Examples of the diisocyanate include aromatic diisocyanate, alicyclic diisocyanate, and aliphatic diisocyanate. Examples of the aromatic diisocyanate include, but are not limited to, diphenylmethane diisocyanate (hereinafter, also referred to as “MDI”), tolylene diisocyanate, 1,4-diisocyanate benzene, xylylene diisocyanate, 2,6-naphthalene diisocyanate, and the like. It is done. Examples of the alicyclic diisocyanate and the aliphatic diisocyanate include methylene bis (cyclohexyl isocyanate) (hereinafter also referred to as “H12MDI”), isophorone diisocyanate, methylcyclohexane 2,4-diisocyanate, methylcyclohexane 2,6-diisocyanate, cyclohexane. Examples thereof include 1,4-diisocyanate, hexahydroxylylene diisocyanate, hexahydrotolylene diisocyanate, and octahydro 1,5-naphthalene diisocyanate. These diisocyanates may be used alone or in combination of two or more. For example, the diisocyanate is preferably an aromatic diisocyanate, more preferably MDI, from the viewpoint of stretch recovery properties of polyurethane elastic yarn required for diaper products.

Polymer polyols include, but are not limited to, polymer diols such as polyether diols, polyester diols, and polycarbonate diols. From the viewpoint of hydrolysis resistance, the polymer polyol is preferably a polyether-based polyol, and more preferably a polyether-based diol.

Examples of the polyether polyol include polyethylene oxide, polyethylene glycol, polyethylene glycol derivatives, polypropylene glycol, polytetramethylene ether glycol (hereinafter also referred to as “PTMG”), a copolymer of tetrahydrofuran (THF) and neopentyl glycol. Examples thereof include modified PTMG (hereinafter also referred to as “PTXG”), and diol which is a copolymer of THF and 3-methyl THF. These polyether polyols may be used alone or in combination of two or more. From the viewpoint of UV embrittlement, the polyether polyol is preferably PTMG, PTXG, and a polyol obtained by blending these.

The chain extender is preferably at least one selected from the group consisting of a low molecular weight diamine and a low molecular weight diol. In addition, as a chain extender, you may have both a hydroxyl group and an amino group in a molecule | numerator like ethanolamine.

Examples of the low molecular weight diamine as the chain extender include, but are not limited to, hydrazine, ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 2-methyl-1,5-pentanediamine, 1, 2-diaminobutane, 1,3-diaminobutane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,2-dimethyl-1,3-diaminopropane, 1,3-diamino-2 , 2-dimethylbutane, 2,4-diamino-1-methylcyclohexane, 1,3-pentanediamine, 1,3-cyclohexanediamine, bis (4-aminophenyl) phosphine oxide, hexamethylenediamine, 1,3-cyclohexyl Diamine, hexahydrometaphenylenediamine, 2-methylpentamethylenediamine , And bis (4-aminophenyl) phosphine oxide, and the like. These low molecular weight diamines may be used alone or in combination of two or more. From the viewpoint of elastic recovery of the elastic yarn, the low molecular weight diamine is preferably a diamine having 2 to 5 carbon atoms, more preferably ethylenediamine.

Examples of the low molecular weight diol include, but are not limited to, ethylene glycol, 1,3 propanediol, 1,4 butanediol, bishydroxyethoxybenzene, bishydroxyethylene terephthalate, 1-methyl-1,2-ethanediol, and the like. It is done. These low molecular weight diols may be used alone or in combination of two or more.

The method for spinning polyurethane elastic yarn is not particularly limited. Examples of the spinning method include a method of dissolving polyurethane in a solvent and spinning by a wet method or a dry method, and a method of heating and melting polyurethane and spinning by a melting method.

In addition, the polyurethane elastic yarn has a polymer or additive other than polyurethane, for example, an antioxidant, a light-resistant agent, an ultraviolet absorber, a gas discoloration inhibitor, a dye, an activator, a gloss as long as the effect of the present application is not lost. It may contain a quencher, a lubricant and the like.

In this embodiment, the weight of the polyurethane elastic yarn alone of the polyurethane elastic thread body (hereinafter simply referred to as “the amount of winding”) may be 4.50 kg or more and 9.00 kg or less, and 4.50 kg or more and 8.00 kg. Or less, more preferably from 4.50 kg to 7.00 kg, and even more preferably from 5.00 kg to 7.00 kg. When the yarn winding amount is 4.50 kg or more, the replacement frequency of the thread body is reduced in the product manufacturing process, and the processability is excellent. When the amount of yarn wound is 9.00 kg or less, the phenomenon that the yarn is pushed out in the winding width direction (hereinafter also simply referred to as “belly swelling”) due to the tightening stress of the polyurethane elastic yarn is suppressed, and used in the product manufacturing process. When doing so, thread breakage is less likely to occur.

In the specification of the present application, the “wound width (W1) of the outermost layer” of the thread body means, as shown in FIG. 2, a polyurethane elastic thread (hereinafter simply referred to as “the outermost layer” exposed on the outermost side of the polyurethane elastic thread body). The width of the outer layer). As shown in FIG. 2, “winding width (W2) of the innermost layer” means the winding width of the polyurethane elastic yarn (hereinafter simply referred to as “innermost layer”) in contact with the tube of the polyurethane elastic yarn thread body. Say. As shown in FIG. 2, the “central thickness (T1)” of the thread body means the thickness of the central part of the outermost layer of the polyurethane elastic thread body. As shown in FIG. 2, the “end portion thickness (T2)” of the thread body refers to the thickness of both ends of the outermost layer of the polyurethane elastic yarn. When the winding thicknesses at both ends of the outermost layer are different, the average value is defined as the winding thickness (T2) at the end portion. The central portion is the thickest portion of the thread body on the line connecting the point obtained by dividing W1 length obtained by measuring W1 with a ruler into two equal parts and the center portion of the thread tube. Refers to the site.

In this embodiment, the ratio (T1 / W1) of the winding thickness (T1) of the center portion of the thread body to the winding width (W1) of the outermost layer may be 0.40 or more and 0.80 or less, and 0 More preferably, it is 40 or more and 0.65 or less. When (T1 / W1) is 0.40 or more, the winding width becomes shorter with respect to the winding thickness. Therefore, in the product manufacturing process, the thread body is placed on the driving roller to actively unwind and remove the yarn. When the unwinding method is used, the necessary space per cheese can be narrowed, and the number of cheeses that can be unraveled at the same time increases. Moreover, when (T1 / W1) is 0.80 or less, the phenomenon that the yarn falls off from the winding width (hereinafter also simply referred to as “falling”) is suppressed when used in the product manufacturing process, and the yarn falls off. Troubles in which the yarn is caught in other parts of the kite body or the manufacturing apparatus and the yarn is cut can be suppressed.

In this embodiment, the ratio (W1 / W2) of the winding width (W1) of the outermost layer and the winding width (W2) of the innermost layer of the thread body may be 0.75 or more and 1.00 or less. More preferably, it is not less than .75 and not more than 0.95. When (W1 / W2) is 0.75 or more, it is possible to prevent the tightening stress from being biased to the center portion, so that the ears are suppressed, and the elastic yarn is fixed by fixing the string body in the diaper manufacturing process. When unwinding in the direction of the end face of the thread body, the elastic thread is not caught on the ears of the thread body and thread breakage is prevented. Moreover, when (W1 / W2) is 1.00 or less, the yarn at the end of the outermost layer is less likely to fall off than the winding width, and the traversing phenomenon can be suppressed.

In this embodiment, the ratio (T1 / T2) of the winding thickness (T1) of the center portion of the thread body to the winding thickness (T2) of the end portion may be 0.85 or more and 1.02 or less. It is preferable that it is 90 or more and 1.00 or less. When (T1 / T2) is 0.85 or more, the winding thickness at both ends does not become too large with respect to the winding thickness at the center of the outermost layer, and the ears are suppressed. Due to the suppression of the ears, when the thread body is fixed and the elastic thread is unwound in the end face direction of the thread body in the product manufacturing process, the elastic thread is caught in the ear of the thread body and the thread breaks. Is suppressed. When (T1 / T2) is 1.02 or less, the winding thickness at both ends of the outermost layer does not become too thicker than the winding thickness at the central portion, so that the twill phenomenon is suppressed.

In this specification, the winding width (W0) of the thread body within 100 m from the start of winding refers to the minimum value of the winding width when measuring an arbitrary 10 m winding width within 100 m from the start of winding.

From the viewpoint of more effectively suppressing the belly swelling during winding or over time of the polyurethane elastic yarn string according to the present embodiment, the winding width of the outermost layer of the string within 100 m from the start of the polyurethane elastic yarn winding. Preferably there is a winding width (W0) in which the ratio (W0 / W1) to (W1) is 0.30 or more and 0.80 or less, and there is a winding width (W0) that is 0.30 or more and 0.70 or less. It is more preferable. Moreover, it is preferable that the winding width (W0) of the thread body within 100 m from the start of winding is within 75 m from the start of winding.

The reason why the stomach bulge can be more effectively suppressed by adjusting the ratio (W0 / W1) to be not less than 0.30 and not more than 0.80 is not yet clear. Is estimated as follows. In the present embodiment, the elastic yarn is used so that the ratio (T1 / T2) of the winding thickness (T1) at the center of the thread body to the winding thickness (T2) at the end is 0.85 or more and 1.02 or less. When winding up, the stress of tightening to the center part becomes large with respect to the end part. On the other hand, by controlling (W0 / W1) to be 0.30 or more and 0.80 or less, the yarn portion within 100 m from the start of winding serves as a cushion against a large tightening stress applied in the center direction, It is considered that the so-called “belly swelling” in which the yarn is pushed out in the winding width direction can be more effectively suppressed. When this (W0 / W1) is 0.30 or more, the area of the cushion portion is increased, and abdominal swelling can be more effectively suppressed. Further, when (W0 / W1) is 0.80 or less, it is considered that the area of the cushion portion does not become too large, and stress is prevented from being dispersed, so that “abdominal swelling” can be more effectively suppressed. It is done. The effect of suppressing the belly bulge becomes more effective when (W0 / W1) is set to 0.30 or more and 0.70 or less.

Furthermore, in order to suppress belly swelling, the ratio of the outermost layer winding width (W1) within the polyurethane elastic yarn string according to the present embodiment within 500 m from the winding start of the polyurethane elastic yarn is 0. The amount of yarn wound with a winding width of 30 or more and 0.80 or less is preferably 0.20 g or more, and more preferably 0.25 g or more. As described above, the reason why the belly bulge can be more effectively suppressed by controlling the winding amount of the yarn within a specific range within 500 m from the start of winding is not yet clear, but the inventors have described the following. It is estimated as follows. As described above, the yarn portion within the range of 500 m from the start of winding plays a cushioning role against a large tightening stress applied in the direction of the central portion, and when the amount of winding of the cushion portion is 0.20 g or more, the cushioning effect It is considered that the “belly swelling” in which the yarn is pushed out in the winding width direction can be more effectively suppressed.

In this embodiment, the twill angle of the polyurethane elastic yarn is preferably greater than 0 degree and 30 degrees or less, and more preferably 5 degrees or more and 25 degrees or less. Further, if the angle is greater than 0 degrees and equal to or less than 30 degrees, the twill angle may change in the cocoon body. In the present embodiment, “twill angle” refers to an angle formed by the rotation direction of the thread body and the thread traversed in the width direction of the thread body. When the twill angle of the polyurethane elastic yarn is 30 degrees or less, the winding hardness does not become too high, and the inner layer yarn of the kite body does not tighten too much, and the belly bulge occurs over time. It can suppress more effectively. When the twill angle of the polyurethane elastic yarn is 5 degrees or more, it becomes difficult for the yarn to fall off from both end faces of the kite thread body, and the twill can be effectively suppressed.

In this embodiment, the elongation percentage of the polyurethane elastic yarn is preferably 0.01% or more and 10% or less, and more preferably 0.2% or more and 5% or less. When the elongation percentage of the polyurethane elastic yarn is 0.01% or more, the ratio (T1 / T2) of the central portion thickness (T1) to the end portion thickness (T2) can be easily set to 1.02 or less. Moreover, twill can be more effectively suppressed. Further, if the elongation rate of the elastic yarn is 10% or less, it becomes easy to set the central portion thickness (T1) / end portion thickness (T2) to 0.85 or more, and the belly swelling over time is more effective. Can be suppressed. The measuring method of the elongation rate of the polyurethane elastic yarn is described in the column of Examples described later.

In this embodiment, a processing agent such as an oil agent may be applied to the polyurethane elastic yarn from the viewpoint of unwinding property, processability, and the like. Examples of the treatment agent include, but are not limited to, silicone oils such as dimethyl silicone, mineral oil oils, and combinations thereof. The method for applying the treatment agent is not particularly limited, and for example, it can be applied by an oiling roller or the like.

<< Method for producing polyurethane elastic yarn body >>
As a method for producing the polyurethane elastic yarn body of this embodiment, the polyurethane elastic yarn is placed in an arbitrary pipe, the amount of winding is 4.5 kg or more and 9 kg or less, the winding thickness (T1) of the central portion and the winding of the outermost layer The ratio (T1 / W1) to the width (W1) is 0.40 or more and 0.80 or less, and the ratio (W1 / W2) between the outermost layer winding width (W1) and the innermost layer winding width (W2) is 0.75 to 1.00, and the ratio (T1 / T2) of the central thickness (T1) to the end thickness (T2) is 0.85 to 1.02. If it can rotate, it will not be specifically limited.

The polyurethane elastic yarn body of the present embodiment can be manufactured using any winding device. Generally, a winding device traverses continuously supplied elastic fibers at a predetermined traverse angle by a traverse guide, passes a drive roll, and puts a thread on a tube such as a paper tube that rotates at the same peripheral speed. A predetermined amount can be wound. Thread switching from a chuck with a fully wound winding side tube to a chuck with an empty standby side tube can be performed automatically or manually continuously. it can. Here, the take-up side chuck refers to a chuck that carries a pipe that takes up a yarn, and the standby side chuck refers to cutting the yarn when the take-up side chuck is fully wound. A chuck that holds an empty tube for continuously switching the thread to the next tube without any problems.

∙ From the viewpoint of improving productivity, it is preferable that each chuck has a plurality of tubes. The tube attached to the take-up side chuck is rotated by a drive roll itself or via the taken-up yarn, and the yarn can be taken up. When the pipe attached to the take-up side chuck winds up a predetermined amount of yarn and becomes fully wound, the drive roll moves away from the take-up side pipe automatically or manually along the traverse guide, and then the turret plate And the tube mounted on the standby chuck can be replaced with a fully wound winding tube and wound around an empty tube. After winding, the drive roll is lowered, and normal winding starts by contacting the wound tube, and the tube switching is completed. At this time, in the winding width (W0) within a range of 100 m from the start of winding, the production of the yarn having the ratio (W0 / W1) to the outermost layer winding width (W1) of 0.30 or more and 0.80 or less. Although a method is not specifically limited, For example, the following method is mentioned. If the time from when the turret plate is rotated and the yarn is wound around the pipe on the standby side until the drive roll comes into contact with the pipe is about 3 seconds or more, the time until the drive roll comes into contact with the pipe, Since there is a gap between the drive roll and the pipe, the winding yarn width can be set smaller than the traverse width. In the winding width (W0) within the range of 100 m from the start of winding, the outermost layer It becomes easier to form a yarn having a ratio (W0 / W1) to the winding width (W1) of 0.30 or more and 0.80 or less. Moreover, since the winding width immediately after the switching can be reduced by reducing the amplitude width of the traverse guide only immediately after the tube switching, it is easier to set (W0 / W1) to 0.30 or more and 0.80 or less. become. Thus, a cushion portion having a small winding width can be wound at the beginning of winding. Further, within 500 m from the start of winding of the polyurethane elastic yarn, the winding amount of the yarn wound at a winding width in which the ratio to the winding width (W1) of the outermost layer is 0.30 or more and 0.80 or less is 0.00. The production method of 2 g or more is not particularly limited. For example, the time from when the turret plate is rotated and the yarn is wound around the pipe on the standby side until the drive roll comes into contact with the pipe or immediately after the pipe is switched. By adjusting the amplitude width of the traverse guide, the winding amount of the yarn wound with the above winding width can be controlled to 0.2 g or more.

Subsequently, the polyurethane elastic yarn thread body of this embodiment is manufactured by setting the twill angle to a value greater than 0 degree and 30 degrees or less, and the elongation rate to an arbitrary value of 0.01% or more and 10% or less. be able to. For example, the polyurethane elastic yarn has a twill angle of greater than 0 degree and no greater than 30 degrees, an elongation of 0.01% or more and 10% or less, and a ratio between the winding thickness (T1) of the central portion and the winding width (W1) of the outermost layer. (T1 / W1) is set to 0.40 or more and 0.80 or less, and winding is performed so that the yarn weight is 4.5 kg or more and 9 kg or less, whereby the outermost layer winding width (W1) and the innermost layer winding width (W2). ) (W1 / W2) is not less than 0.75 and not more than 1.00, and the ratio (T1 / T2) of the central portion thickness (T1) to the end portion thickness (T2) is 0.85. A polyurethane elastic yarn body having a thickness of 1.02 or less can be produced more easily.

In the following examples, the present embodiment will be described more specifically, but the scope of the present invention is not limited thereto.
First, the evaluation method in the present invention will be described.

<< Measurement method and evaluation method >>
<Measurement of the length from the beginning of winding>
In the polyurethane elastic yarn body, the yarn length from the end of the innermost layer was measured as the length from the start of winding. However, in the case where the end thread of the innermost layer portion is provided with the transfer tail yarn for connecting the end yarn of the outermost layer portion of the new elastic yarn end thread body, The length was measured.
<Elongation rate>
The elongation percentage (%) of the polyurethane elastic yarn was measured and calculated by the following procedures (1) to (3).
(1) A polyurethane elastic yarn was unwound from a polyurethane elastic yarn body in a relaxed length (hereinafter also simply referred to as “relaxed length”) for 0.5 m to obtain a sample, and the sample weight (g) was measured. . From the following calculation formula, the fineness (relaxation fineness A (dt)) of the polyurethane elastic yarn in the relaxed state was calculated. The measurement was performed 4 times and the average value was taken. The “relaxed state” refers to a state where the yarn is unwound for 2 hours or more after being unwound from the cheese.
Relaxation fineness A (dt) = sample weight (g) × 10000 / relaxation length (m)
(2) The polyurethane elastic yarn was unwound by being fed by 50 m while maintaining the elongation rate from the polyurethane elastic yarn body by the feeding roll. The weight (g) of the unwinded yarn was measured. From the following calculation formula, the fineness (print fineness B (dt)) of the polyurethane elastic yarn in the stretched state was calculated.
Print fineness B (dt) = Total weight of unraveled yarn (g) × 10000/50 (m)
(3) The elongation percentage (%) of the polyurethane elastic yarn was calculated from the following formula.
Elongation rate (%) = (A / B-1) × 100

<Falling>
After two or more days had passed since the production of the polyurethane elastic yarn body, the falling was observed and evaluated in the following five stages.
5: No thread dropped on the side surface of the thread body.
4: There is only one thread that is less than 5 cm on the side of the thread body.
3: There are a plurality of threads that have fallen below 5 cm on the side surface of the thread body, but there are no threads that have fallen 5 cm or more.
2: There is only one thread that has fallen 5 cm or more on the side surface of the thread body.
1: There are a plurality of dropped threads of 5 cm or more on the side surface of the thread body.

<Swelling belly>
After two or more days have passed since the production of the polyurethane elastic yarn body, the belly bulge was observed and evaluated according to the following five levels.
5: There is no portion having a winding width 2% or more larger than the winding width (W2) of the innermost layer.
4: There is a portion where the winding width is 2% or more and less than 3% larger than the winding width (W2) of the innermost layer.
3: There is a portion having a winding width 3% or more and less than 4% larger than the winding width (W2) of the innermost layer.
2: There is a portion having a winding width that is 4% or more and less than 5% larger than the winding width (W2) of the innermost layer.
1: There is a portion having a winding width 5% or more larger than the winding width (W2) of the innermost layer.

<Ears>
After two or more days have passed since the production of the polyurethane elastic yarn body, the ears were observed by the following method and evaluated in five stages.
The stress was measured when the polyurethane elastic yarn body was depolarized in the direction of the end face of the yarn body at 15 m / min. The measurement was performed for 5 minutes and the average value was recorded. Here, the negative solution means a method of solving by a vertical method.
5: Less than 15 gf.
4: It is 15 gf or more and less than 20 gf.
3: 20 gf or more and less than 25 gf.
2: It is 25 gf or more and less than 30 gf.
1:30 gf or more or thread breakage.

<Winding shape>
The wound shape of the elastic thread body was observed and evaluated in the following five stages.
5: Twill fell, belly swollen, and ears were all rated 5 and the wound shape was very good. Thread breakage does not occur in the diaper manufacturing process.
4: Evaluation 4 is given to any of twill fall, belly swelling, and ears, but evaluations 3, 2, and 1 are not seen, and the winding shape is good. Thread breakage does not occur in the diaper manufacturing process.
3: Evaluation is 3 in any of twill fall, belly bulge, and ears, but evaluations 2 and 1 are not seen, and there is no abnormality in winding shape. There is almost no thread breakage in the diaper manufacturing process.
2: Evaluation 2 is given to any of twill, belly bloating, and ears, but evaluation 1 is not seen. Thread breaks occur rarely in the diaper manufacturing process.
1: Evaluation 1 is observed in any of twill fall, belly bulge, and ears, and the overall winding shape is not good. Thread breaks occur frequently in the diaper manufacturing process.

<Production example of polyurethane elastic thread body>
[Examples 1 to 3]
Winding amount of yarn wound from a polyurethane spinning dope with a yarn fineness of 620 dt and a ratio of 0.30 or more and 0.80 or less with the outermost layer winding width (W1) within 500 m from the start of winding. Is 8.00 g, the twill angle is 20 degrees, the elongation is 2%, the yarn weight, the winding thickness of the central portion (T1) / the winding width of the outermost layer (W1), the winding width of the outermost layer (W1) / Table 1 shows the innermost layer winding width (W2), the central portion winding thickness (T1) / the end portion winding thickness (T2), the winding width within 100 m from the beginning of winding (W0) / the outermost layer winding width (W1). The polyurethane elastic yarn bodies of Examples 1 to 3 were produced by changing as shown in FIG.
Although the evaluation 4 was observed on some of the ears, the winding shape was good in all cases. The results are summarized in Table 1 below.

[Examples 4 to 6]
With a winding width from the polyurethane spinning dope with a yarn fineness of 620 dt, a yarn weight of 7.00 kg, and a ratio with the outermost layer winding width (W1) within 500 m from the start of winding of 0.30 or more and 0.80 or less. The wound amount of the wound yarn is 8.00 g, the elongation is 2%, the winding thickness of the central portion (T1) / the winding width of the outermost layer (W1), the winding width of the outermost layer (W1) / the innermost layer The winding width (W2), central winding thickness (T1) / end winding thickness (T2), winding width within 100 m from the start of winding (W0) / outermost winding width (W1), and twill angle The polyurethane elastic yarns of Examples 4 to 6 were produced by changing as shown in FIG.
Although evaluation 3 was observed in twill, belly swelling, and part of the ears, no abnormality was observed in the winding shape in any case. The results are summarized in Table 1 below.

[Examples 7 to 9]
With a winding width from the polyurethane spinning dope with a yarn fineness of 620 dt, a yarn weight of 7.00 kg, and a ratio with the outermost layer winding width (W1) within 500 m from the start of winding of 0.30 or more and 0.80 or less. The winding amount of the wound yarn is 8.00 g, the twill angle is 20 degrees, the winding thickness of the central portion (T1) / the winding width of the outermost layer (W1), the winding width of the outermost layer (W1) / the innermost layer Winding width (W2), central portion winding thickness (T1) / end portion winding thickness (T2), winding width within 100 m from the beginning of winding (W0) / outermost layer winding width (W1), and elongation rate. The polyurethane elastic yarns of Examples 7 to 9 were produced by changing as shown in FIG.
Although the evaluation 4 was observed on some of the ears, the winding shape was good in all cases. The results are summarized in Table 1 below.

[Examples 10 to 13]
Polyurethane spinning stock solution with yarn fineness of 620 dt, yarn weight of 7.00 kg, twill angle of 20 degrees, elongation rate of 2.0%, central part winding thickness (T1) / outermost layer winding width (W1 ), Outermost layer winding width (W1) / innermost layer winding width (W2), central portion winding thickness (T1) / end portion winding thickness (T2), winding width within 100 m from the beginning of winding (W0) / The winding amount of the yarn wound at the winding width (W1) of the outermost layer and the ratio of the winding width (W1) of the outermost layer within the range of 500 m from the start of winding to be 0.30 or more and 0.80 or less. The polyurethane elastic yarns of Examples 10 to 13 were produced by changing as shown in Table 1.
Although the evaluation 4 was observed on some of the ears, the winding shape was good in all cases. The results are summarized in Table 1 below.

[Examples 14 to 16]
Polyurethane spinning stock solution with yarn fineness of 620 dt, yarn weight of 7.00 kg, elongation rate of 2%, central thickness (T1) / outermost layer width (W1), outermost layer width (W1) ) / The innermost layer winding width (W2), the central portion winding thickness (T1) / the end portion winding thickness (T2), the winding width within 100 m from the beginning of winding (W0) / the outermost layer winding width (W1), As shown in Table 1, the winding amount and the twill angle of the yarn wound with a winding width within a range of 500 m from the start of winding and a ratio with the winding width (W1) of the outermost layer being 0.30 or more and 0.80 or less. The polyurethane elastic thread bodies of Examples 14 to 16 were manufactured by changing the above.
Evaluation 2 was observed on the fallen ears, swollen stomach, and some of the ears. The results are summarized in Table 1 below.

[Comparative Example 1]
Polyurethane spinning dope with yarn fineness of 620 dt, yarn weight of 7.00 kg, center thickness (T1) / outermost layer width (W1) 0.84, outermost layer width (W1) / The winding width (W2) of the innermost layer is 0.73, the winding thickness (T1) of the central portion / the winding thickness (T2) of the end portion is 0.92, and the winding width (W0) within 100 m from the start of winding / outermost layer The winding width (W1) of the yarn is 0.24 and the ratio of the winding width (W1) of the outermost layer within 500 m from the beginning of winding is 0.30 to 0.80. A polyurethane elastic yarn body of Comparative Example 1 having a winding amount of 0 g, a twill angle of 40 degrees, and an elongation percentage of 2% was produced.
Twill fall and belly bulge were evaluated 1 and yarn breakage occurred frequently in the diaper manufacturing process. The results are summarized in Table 1 below.

[Comparative Example 2]
Polyurethane spinning stock solution with yarn fineness of 620 dt, yarn weight of 7.00 kg, central part thickness (T1) / outermost layer winding width (W1) of 0.52, outermost layer winding width (W1) / The winding width (W2) of the innermost layer is 0.91, the winding thickness (T1) of the central portion / the winding thickness (T2) of the end portion is 0.77, and the winding width (W0) / maximum winding width within 100 m from the start of winding. Yarn wound with a winding width (W1) of the outer layer of 0.47 and a ratio with the outermost layer winding width (W1) of 0.30 or more and 0.80 or less within 500 m from the start of winding. A polyurethane elastic yarn body of Comparative Example 2 having a winding amount of 8.0 g, a twill angle of 20 degrees, and an elongation percentage of 12% was produced.
Ears were rated 1 and yarn breaks occurred frequently in the diaper manufacturing process. The results are summarized in Table 1 below.

[Comparative Example 3]
Polyurethane spinning undiluted solution with yarn fineness of 620 dt, yarn weight of 7.00 kg, central thickness (T1) / outermost layer width (W1) of 0.66, outermost layer width (W1) / The winding width (W2) of the innermost layer is 0.73, the winding thickness (T1) of the central portion / the winding thickness (T2) of the end portion is 0.81, and the winding width (W0) / maximum winding width within 100 m from the start of winding. The outer layer winding width (W1) is 0.58, and the ratio of the outer layer winding width (W1) within 500 m from the start of winding is 0.30 to 0.80. A polyurethane elastic yarn body of Comparative Example 3 having a winding amount of 0.1 g, a twill angle of 20 degrees, and an elongation percentage of 2% was produced.
Ears were rated 1 and yarn breaks occurred frequently in the diaper manufacturing process. The results are summarized in Table 1 below.

The present invention has industrial applicability in the manufacture of innerwear, stockings, compression wear, diapers and the like.

DESCRIPTION OF SYMBOLS 10 Polyurethane elastic thread body 11 Polyurethane elastic thread 12 Cushion part 20 Tube W0 Cushion part winding width W1 Outermost layer winding width W2 Innermost layer winding width T1 Central part winding thickness T2 End part winding thickness

Claims

The amount of winding of the polyurethane elastic yarn wound body from which the polyurethane elastic yarn is wound is 4.50 kg or more and 9.00 kg or less, and the winding thickness (T1) of the center portion of the wound yarn body and the winding width (W1) of the outermost layer (T1 / W1) is 0.40 or more and 0.80 or less, and the ratio (W1 / W2) of the outermost layer winding width (W1) to the innermost layer winding width (W2) is 0.75. The ratio (T1 / T2) of the winding thickness (T1) of the central portion and the winding thickness (T2) of the end portion is 0.85 or more and 1.02 or less. A polyurethane elastic thread body characterized by the above.
The ratio (W0 / W1) of the winding width (W0) of the kite body and the winding width (W1) of the outermost layer within 100 m from the start of winding of the polyurethane elastic yarn is 0.30 or more and 0.80 or less. The polyurethane elastic yarn body according to claim 1.
Within 500 m from the start of winding of the polyurethane elastic yarn, the winding amount of the yarn wound at a winding width in which the ratio to the winding width (W1) of the outermost layer is 0.30 or more and 0.80 or less is 0.20 g. The polyurethane elastic thread body according to claim 2, which is as described above.
The polyurethane elastic yarn thread according to any one of claims 1 to 3, wherein a twill angle of the polyurethane elastic yarn is larger than 0 degree and not larger than 30 degrees.
The polyurethane elastic yarn thread according to any one of claims 1 to 4, wherein the elongation percentage of the polyurethane elastic yarn is 0.01% or more and 10% or less.