JP2001146636A - Multifilament elastic yarn and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a multifilament elastic yarn having a small unevenness of fineness in the longitudinal direction of the yarn and capable of providing a product excellent in quality to afford a uniform knitted surface when the elastic yarn is covered with polyamide fibers, etc., converted into a textured yarn and used for applications of panty hose. SOLUTION: This multifilament elastic yarn is characterized in that the elastic yarn comprises two or more yarns composed of one or more single filaments and the yarns are collected without causing the bonding or adhesion thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a multifilament elastic yarn and a method for producing the same.

More specifically, when a yarn having a small fineness unevenness in the longitudinal direction, covered with a polyamide fiber or the like, and used as a processed yarn for panty stocking, a product having a uniform knitting surface and excellent quality is obtained. The present invention relates to a multifilament elastic yarn capable of forming and a method for producing the same.

[0003]

2. Description of the Related Art A multifilament elastic yarn is covered with polyamide fiber or the like in a single or double manner.
Single coated elastic yarn (SCY) or double coated elastic yarn (DC
Y) is used for foundations, socks, pantyhose and the like.

As disclosed in Japanese Patent Application Laid-Open No. Hei 9-217227, for example, a conventional multifilament elastic yarn is formed by joining filaments together in a sticky state at a spinning stage and winding the yarn around a bobbin or the like. Was normal.

[0005]

However, in the prior art, the unevenness of fineness in the longitudinal direction of the yarn is large, and when used in pantyhose, etc., the surface knitted surface is not uniform, resulting in a defect called "hikemura". There was a problem that occurs.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems. When the fineness unevenness in the longitudinal direction of the yarn is small, the yarn is covered with polyamide fiber or the like, and is used as a processed yarn for pantyhose use. It is another object of the present invention to provide a multifilament elastic yarn capable of obtaining a product having a uniform knitting surface and excellent quality.

[0007]

The multifilament elastic yarn of the present invention has the following structure to solve the above problems.

That is, a multifilament elastic yarn composed of two or more yarns composed of one or more single yarns, wherein the yarns are converged without adhesion or sticking. Multifilament elastic yarn.

Further, the method for producing a multifilament elastic yarn of the present invention has the following constitution in order to solve the above problems.

That is, in producing a multifilament elastic yarn by converging two or more yarns composed of one or more single yarns, after substantially completely removing the medium on the yarn surface, the yarn is removed. And a method for producing a multifilament elastic yarn.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

[0012] The multifilament elastic yarn of the present invention comprises:
It consists of a yarn composed of more than one single yarn.

The present invention is a multifilament elastic yarn. In the present invention, the multifilament refers to one composed of two or more yarns, and each yarn is composed of an elastic yarn.

In the present invention, the elastic yarn means a yarn formed of an elastic polymer.
For example, at least one selected from synthetic rubber, polyolefin elastomer, polyester elastomer, polyurethane and the like can be used.

In the present invention, a polyurethane polymer is particularly preferably used. The polyurethane polymer may be a polyurethane-urea copolymer, or a mixture or a copolymer of polyurethane and polyurethane-urea.

More specifically, the polyurethane polymer used in the present invention comprises two types of segments: (a) a long-chain polyether, a soft segment which is a polyester segment, and (b) an organic isocyanate and a diamine chain extension. A hard segment, which is a relatively short chain segment derived by reaction with an agent or a diol chain extender.

Usually, such a polyurethane polymer may be obtained by a prepolymer method in which a prepolymer product obtained by capping a hydroxyl-terminated soft segment precursor with an organic diisocyanate is chain-extended with a diamine or a diol, or May be obtained by a one-shot method in which all the raw materials are put in the same bath and polymerized,
Also, it may be obtained by other methods.

A typical polyether soft segment is polytetramethylene ether glycol (hereinafter referred to as P
TMG), those derived from 3-methyl-1,5-pentanediol, tetrahydrofuran, 3-methyltetrahydrofuran, and the like, and copolymers thereof. Among them, a polyether derived from polytetramethylene ether glycol is preferred. Typical polyester soft segments include (a) ethylene glycol, polytetramethylene ether glycol, 2,2-dimethyl-1,3-propanediol, and (b) dibasic acids such as adipic acid and succinic acid. And the like.

The soft segment is formed from typical polyethers and polyesters, or from polycarbonate diols such as poly- (pentane-1,5-carbonate) diol and poly- (hexane-1,6-carbonate) diol. It may be a copolymer such as a modified polyetherester.

Typical examples of the organic diisocyanate used in the present invention are bis- (p-isocyanatophenyl) -methane (hereinafter abbreviated as MDI), tolylene diisocyanate (hereinafter abbreviated as TDI), bis- (4-isocyanate). Cyclohexyl) -methane (hereinafter abbreviated as PICM),
Hexamethylene diisocyanate, 3,3,5-trimethyl-5-methylenecyclohexyl diisocyanate and the like. Among them, MDI is particularly preferred.

Various diamines, for example, ethylenediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine and the like are suitable as chain extenders for forming polyurethaneurea. Chain terminators can be included in the reaction mixture to help control the final molecular weight of the polyurethaneurea. Usually, it is preferable to use a monofunctional compound having an active hydrogen as the chain terminator, for example, diethylamine.

Further, the chain extender is not limited to the above-mentioned amine, and a diol may be used. For example, ethylene glycol, 1,3-propanediol, 4-butanediol, neopentyl glycol,
1,2-propylene glycol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol,
1,4-bis (β-hydroxyethoxy) benzene, bis (β-hydroxyethyl) terephthalate and paraxylylene diol. The diol chain extender is 1
The diol is not limited to only one kind of diol, and may be composed of plural kinds of diols. Further, it may be used in combination with a compound containing one hydroxyl group that reacts with an isocyanate group. In this case, as a method for obtaining such a polyurethane, various methods such as a melt polymerization method and a solution polymerization method can be adopted. The method of polymerization is not particularly limited, and examples thereof include a method of synthesizing a polyurethane by simultaneously reacting a polyol, a diisocyanate, and a chain extender composed of a diol, and the like. Good.

In the present invention, the polyurethane polymer may be a benzotriazole-based ultraviolet absorber, a hindered amine-based weathering agent, a hindered phenol-based antioxidant, various pigments such as titanium oxide and iron oxide, and barium sulfate. , A functional additive containing zinc oxide, cesium oxide, silver ions and the like.

In the present invention, the polyurethane polymer is preferably used as a polyurethane solution by using a solvent, and is also preferably used as a polyurethane dispersion by using a dispersion medium. preferable.

In the present invention, these solutions, dispersions and mixtures thereof are collectively referred to as stock solutions. Also,
In the present invention, a solvent, a dispersion medium, and a mixture thereof are collectively referred to as a medium.

A medium such as a solvent or a dispersion medium used for dissolving or dispersing the polyurethane polymer includes:
Any material may be used as long as it is inert to the polyurethane, but N, N-
It is preferable to use dimethylacetamide (hereinafter abbreviated as DMAc), dimethylformamide, dimethylsulfoxide, vinylpyrrolidone, or the like.

The concentration of the stock solution is not particularly limited, but is usually preferably in the range of 25% by weight to 80% by weight.

More preferably, 30% by weight or more and 60% by weight or more.
The range is as follows, and more preferably 35% by weight or more.
The range is 5% by weight or less.

If the content is less than 25% by weight, the amount of heat required for evaporation of a solvent or the like during dry spinning increases, and spinning tends to be difficult.

On the other hand, if the content exceeds 80% by weight, the stability of the stock solution deteriorates, as a result, the spinnability deteriorates, and if the degree of polymerization of the polymer is reduced to improve the stability of the stock solution, the yarn quality tends to deteriorate. There is.

The viscosity of the stock solution is 2500 poise or more and 5500
It is preferably equal to or less than poise. If the viscosity is 2500 poise or more, the yarn breakage due to the decrease in the viscosity during dry spinning is small, and the spinnability is good. If the viscosity is 5500 poise or less, the pressure loss at the die portion can be suppressed to some extent. Yarn quality can be improved.

The value of the viscosity is based on a steel ball drop type viscosity measurement method at 40 ° C.

The multifilament elastic yarn of the present invention can be obtained by spinning the polyurethane polymer. As a spinning method that can be adopted, any method such as a dry spinning method, a melt spinning method, and a wet spinning method may be used.

In the present invention, a dry spinning method can be particularly preferably employed. Spinning conditions such as the temperature of the stock solution, the ambient temperature, the discharge speed, the shape of the die, and the yarn take-up speed during dry spinning can be appropriately selected. The number of holes in the die is one or more to form one or more single yarns.

The multifilament elastic yarn of the present invention comprises:
Two or more yarns composed of a single yarn or more are converged without adhesion or sticking.

The yarn in the present invention is composed of one or more single yarns. When there are two or more such single yarns,
There may be a portion to be joined between the single yarns.

The number of single yarns is not particularly limited.
About 0 or less is preferable.

In the present invention, two or more yarns are used. In particular, the number of yarns is preferably in a range of 2 or more and 20 or less.

The fineness of the multifilament elastic yarn of the present invention is preferably 5.6 to 344 dtex.

An example of the multifilament elastic yarn of the present invention will be specifically described. For example, three yarns having a yarn fineness of 26 dtex (23 denier) converge to a joined state without bonding or sticking. In the case of a multifilament elastic yarn having a total fineness of 77 dtex (69 denier), either one or three single yarns constituting the yarn may be used.

The multifilament elastic yarn of the present invention is one in which the yarns are converged without adhesion or sticking. In the present invention, a state in which the yarns converge without bonding or sticking is a state in which the yarns softened or melted in the spinning step are bonded or sticked together to form an apparently single yarn. Rather, it refers to a state in which the yarns converge without adhering or sticking, and in the converged state, there may be portions where the yarns are entangled with each other.

The converged state may be a state in which the yarn and another yarn are joined, but the yarn and the yarn are not adhered or adhered to each other, and each of the yarns is caused by a slight external force. The strips are easily separated. Alternatively, the yarn may not be in a state where the yarn and another yarn are joined, but may be in a slightly separated state. In the longitudinal direction of the yarn, the yarn may alternately have a state in which the yarn and another yarn are joined and a state in which the yarn is slightly separated. Further, there may be portions where the yarns are entangled with each other. The state in which the yarns are entangled with each other means that the yarns are in a state of being entangled with each other in a partially twisted or crossed state.

An example of the multifilament elastic yarn of the present invention will be described with reference to the drawings. FIG. 1 shows that the total fineness is 77 dtex (69 denier), and one single yarn 21
And a state in which three yarns 22 having a fineness of 26 dtex (23 denier) are converged without bonding or sticking.

FIG. 2 shows that the total fineness is 77 dtex (69
(Denier), and shows a state in which three yarns 22 composed of three single yarns 21 and having a fineness of 26 dtex (23 denier) are converged without being adhered or adhered.

FIGS. 1 and 2 show a portion where the yarns are slightly separated from each other.

In order to obtain such a yarn, it is important that, when producing the multifilament elastic yarn, the medium on the surface of the yarn is substantially completely removed before the yarn is converged.

If the yarns are converged before the medium on the surface of the yarn is substantially completely removed, the yarns are bonded to each other, and the yarn spots become large.

Hereinafter, the method for producing a multifilament elastic yarn of the present invention will be described with reference to the drawings, in the case of dry spinning.

FIG. 3 is a schematic view showing an example of a process for producing the multifilament elastic yarn of the present invention.

The elastic polymer solution is discharged from the spinneret 11 into the yarn F, and then heated to substantially completely remove the medium on the yarn surface. The heating may be performed from a spinning cylinder or using a heating gas. Further, these may be used in combination. In the present invention, from the viewpoint of thermal efficiency, a method performed from a heating gas and a spinning cylinder is preferable.

In the present invention, substantially completely removing the medium on the surface of the yarn means evaporating the liquid medium by heating the medium to a temperature higher than the boiling point of the medium.

The shape of the spinning cylinder may be circular, rectangular, polygonal, or any other form.

It is preferable that the heating gas is appropriately selected depending on the type of the volatile component of the medium. When the volatile component is a volatile organic solvent, it is preferable to use mainly an inert gas.

The thus heated yarns can be guided to the winding device 16 via the first feed roll 12, the oil applying roll 14, and the second feed roll 15 without converging.

In the present invention, the yarn is converged after the medium existing on the yarn surface is substantially completely removed. In the present invention, it is preferable to use a guide to converge the yarn, but it may be converged by another method.

Such a guide may be provided at any position after the medium existing on the yarn surface has been substantially completely removed, but usually the first feed roll 14 is provided as shown in FIG. It is preferable to provide between the second feed roll 15 and the second feed roll 15 or between the second feed roll 15 and the winding device 16 as shown in FIG.

In the present invention, the intertwining of the yarn is
By reciprocating the traverse guide of the winding machine in a direction perpendicular to the running direction of the yarn, the yarn can be twisted and the yarn entangled when the yarn is wound on the bobbin.

The material of the guide is preferably titanium, ceramic or the like from the viewpoint of preventing yarn breakage due to frictional resistance.

[0059]

EXAMPLES The multifilament elastic yarn of the present invention will be described below in detail with reference to examples.

Example 1 2000 g of polytetramethylene ether glycol having a molecular weight of 2,000 and 400 g of diphenylmethane diisocyanate were charged into a stirring vessel sealed with nitrogen and reacted at 90 ° C. to obtain a prepolymer. Next, 699 g of this prepolymer was dissolved in 1288 g of dimethylacetamide, and 11 g of ethylenediamine as a chain extender and 1.6 g of diethylamine as a terminal blocking agent were added so that the molar ratio to the prepolymer was 1.05. The mixture was stirred and reacted at ℃ to obtain a polyurethane solution.

A stabilizer prepared by adjusting a modifier such as titanium oxide to a weight ratio of 6% was added to this polyurethane solution.
Added and stirred.

When the number average molecular weight of the polyurethane contained in the obtained polyurethane solution was measured by GPC method,
It was about 38,000 in terms of polystyrene.

The polyurethane solution is extruded from a spinneret and heated in a spinning cylinder so that the residual solvent on the surface becomes substantially 0% by the time the formed yarn reaches the first feed roll. The temperature of the gas, the air volume, and the temperature of the spinning cylinder were adjusted, and the film was wound at a winding speed of 1150 m / min. The convergence of the yarn was performed by a guide provided between the first feed roll and the second feed roll. The obtained multifilament has a fineness of 78 dtex (70 denier) and a single yarn of 1
Three of the yarns had been converged. The obtained yarn was of excellent quality with small yarn spots.

Example 2 1386 g of polytetramethylene ether glycol having a molecular weight of 2200, 472 g of diphenylmethane diisocyanate and 78 g of ethylene glycol were charged into 3064 g of dimethylacetamide.
The reaction was carried out at 85 ° C. in a stirred vessel sealed with nitrogen, and 20 g of butanol was added to obtain a polyurethane solution.

A stabilizer prepared by adding a modifier such as titanium oxide to a weight ratio of 6% was added to the polyurethane solution.
Added and stirred.

When the number average molecular weight of the polyurethane contained in the obtained polyurethane solution was measured by GPC method,
It was about 90,000 in terms of polystyrene.

This polyurethane solution is extruded from a spinneret and heated in a spinning cylinder so that the residual solvent on the surface becomes substantially 0% by the time the formed yarn reaches the first feed roll. The temperature of the gas, the air volume, and the temperature of the spinning cylinder were adjusted, and the film was wound at a winding speed of 1150 m / min. The convergence of the yarn was performed by a guide provided between the first feed roll and the second feed roll. The obtained multifilament had a fineness of 78 dtex (70 denier) and 3 single yarns.
Three of the yarns had been converged. The obtained yarn was of excellent quality with small yarn spots.

Example 3 2000 g of polytetramethylene ether glycol having a molecular weight of 2,000 and 400 g of diphenylmethane diisocyanate were charged into a stirring vessel sealed with nitrogen and reacted at 90 ° C. to obtain a prepolymer. Next, 699 g of this prepolymer was dissolved in 1288 g of dimethylacetamide, and 11 g of ethylenediamine as a chain extender and 1.6 g of diethylamine as a terminal blocking agent were added so that the molar ratio to the prepolymer was 1.05. The mixture was stirred and reacted at ℃ to obtain a polyurethane solution.

When the number average molecular weight of the polyurethane contained in the obtained polyurethane solution was measured by GPC method,
It was about 38,000 in terms of polystyrene.

The polyurethane solution is extruded from a spinneret and heated in a spinning cylinder so that the residual solvent on the surface becomes substantially 0% by the time the formed yarn reaches the first feed roll. Gas temperature (440 ° C), air volume,
The temperature of the spinning cylinder (230 ° C) is adjusted and the winding speed is 651m
/ Min. The convergence of the yarn was performed by a guide provided between the first feed roll and the second feed roll. The resulting multifilament has a fineness of 156 dtex,
Three yarns having five single yarns were converged. The obtained yarn was of excellent quality with small yarn spots.

Example 4 2000 g of polytetramethylene ether glycol having a molecular weight of 2,000 and 400 g of diphenylmethane diisocyanate were charged into a nitrogen-sealed stirring vessel and reacted at 90 ° C. to obtain a prepolymer. Next, 699 g of this prepolymer was dissolved in 1288 g of dimethylacetamide, and 11 g of ethylenediamine as a chain extender and 1.6 g of diethylamine as a terminal blocking agent were added so that the molar ratio to the prepolymer was 1.05. The mixture was stirred and reacted at ℃ to obtain a polyurethane solution.

When the number average molecular weight of the polyurethane contained in the obtained polyurethane solution was measured by GPC method,
It was about 38,000 in terms of polystyrene.

The polyurethane solution is extruded from a spinneret and heated in a spinning cylinder so that the residual solvent on the surface becomes substantially 0% by the time the formed yarn reaches the first feed roll. Gas temperature (360 ° C), air volume,
The spinning cylinder temperature (205 ° C) is adjusted and the winding speed is 661m
/ Min. The convergence of the yarn was performed by a guide provided between the first feed roll and the second feed roll. The obtained multifilament had a fineness of 33 decitex and four monofilament yarns were converged. The obtained yarn was of excellent quality with small yarn spots.

Example 5 2000 g of polytetramethylene ether glycol having a molecular weight of 2,000 and 400 g of diphenylmethane diisocyanate were charged into a stirring vessel sealed with nitrogen and reacted at 90 ° C. to obtain a prepolymer. Next, 699 g of this prepolymer was dissolved in 1288 g of dimethylacetamide, and 11 g of ethylenediamine as a chain extender and 1.6 g of diethylamine as a terminal blocking agent were added so that the molar ratio to the prepolymer was 1.05. The mixture was stirred and reacted at ℃ to obtain a polyurethane solution.

When the number average molecular weight of the polyurethane contained in the obtained polyurethane solution was measured by GPC method,
It was about 38,000 in terms of polystyrene.

The polyurethane solution is extruded from a spinneret and heated in a spinning cylinder so that the residual solvent on the surface becomes substantially 0% by the time the formed yarn reaches the first feed roll. Gas temperature (350 ° C), air volume,
The spinning cylinder temperature (205 ° C) is adjusted and the winding speed is 567m
/ Min. The convergence of the yarn was performed by a guide provided between the first feed roll and the second feed roll. The resulting multifilament had a fineness of 44 decitex and four monofilament yarns were converged. The obtained yarn was of excellent quality with small yarn spots.

Comparative Example 1 Example 1 was repeated except that a convergence guide was provided between the exit of the spinning cylinder and the first feed roll to converge the yarn before the solvent on the surface of the single yarn was substantially completely removed. The same conditions were used. The obtained yarn was larger than that of the example.

[0078]

Industrial Applicability According to the present invention, a product having a small fineness unevenness in the longitudinal direction of the yarn, covering with polyamide fiber or the like, and having a uniform knitting surface when used as a processed yarn for pantyhose use is obtained. A multifilament elastic yarn capable of being obtained can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view schematically showing one example of a multifilament elastic yarn of the present invention.

FIG. 2 is a schematic sectional view schematically showing another example of the multifilament elastic yarn of the present invention.

FIG. 3 is a schematic view showing an example of a process for producing the multifilament elastic yarn of the present invention.

FIG. 4 is a schematic view showing another example of the process for producing the multifilament elastic yarn of the present invention.

[Explanation of symbols]

 11: Spinneret 12: First feed roll 13: Guide 14: Oil supply roll 15: Second feed roll 16: Winding device F: Yarn 21: Single yarn 22: Yarn

Claims (6)

[Claims] 1. A multifilament elastic yarn comprising two or more yarns composed of one or more single yarns, wherein the yarns are converged without adhesion or sticking. Multifilament elastic yarn. 2. The multifilament elastic yarn according to claim 1, wherein the elastic yarn is a polyurethane elastic yarn or a polyurethane urea elastic yarn. 3. The multifilament elastic yarn according to claim 1, wherein the number of yarns is 2 or more and 20 or less. 4. In producing a multifilament elastic yarn by converging two or more yarns composed of one or more single yarns, after substantially completely removing a medium on the surface of the yarn, the yarn is removed. And a method for producing a multifilament elastic yarn. 5. The method for producing a multifilament elastic yarn according to claim 4, wherein the converged yarns are entangled with each other. 6. The method for producing a multifilament elastic yarn according to claim 4, wherein the medium on the yarn surface is substantially completely removed using a gas.