JPH08120527A - Production of urethane elastic fiber - Google Patents

Abstract

PURPOSE: To suppress the fusion of yarns in melt spinning and an increase in sticking with time and prevent the yarn jumping or package collapse on a bobbin from occurring by applying a specific oil agent in spinning to a solidified yarn after melt spinning. CONSTITUTION: A urethane polymer is melt spun and the spun yarn is solidified. An aqueous emulsion containing a polyether amine of the formula [X is H or NH2 ; Y1 and Y2 are each independently C-C or formula II; (m) and (n) are each independently an optional integer] is then applied to the solidified spun yarn and a nonaqueous oil agent is subsequently applied thereto. The oiled spun yarn is then wound. Thereby, sticking of the yarn surface to a bobbin in spinning due to active isocyanate groups is only slightly caused and the package form of the spinning bobbin is good to reduce the yarn breakage in the subsequent step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyurethane elastic fiber by a melt spinning method.

More specifically, when melt-spinning polyurethane elastic fibers, it prevents sticking of the yarns on the spinning bobbin and improves the unwinding property of the yarns in the subsequent processing step.
The present invention relates to a method for maintaining proper slippage of a yarn, preventing traverse and collapse of a spinning bobbin, etc., and stabilizing operability in spinning and subsequent processing steps.

[0003]

2. Description of the Related Art Melt spinning method, dry spinning method, wet spinning method and the like have been conventionally used as a method for obtaining polyurethane elastic fiber, and recently, in order to improve stretchability and heat resistance of urethane yarn. A method of mixing and spinning a prepolymer having an active isocyanate group is often used. In any of these methods, when the fiber is wound during spinning, the fibers stick to each other, which makes it difficult to pull out the yarn due to the resistance to sticking when unwinding and pulling the yarn from the bobbin in the subsequent process. In this case, thread breakage occurs, and a situation occurs in which smooth operation cannot be performed. In particular, in the prepolymer mixed spinning method in which a large amount of active isocyanate groups are present, this sticking is remarkable, and with the addition of a usual oil agent, it is not possible to obtain a thread which can be drawn out in the subsequent step.

As a method of preventing the polyurethane from sticking, solid fine particles of talc, silica, colloidal alumina or the like are applied to the fiber as an aqueous or oily slurry, and a metal salt powder of a higher fatty acid is dispersed in water or mineral oil. Method (Japanese Patent Publication No. 41-286, Japanese Patent Publication No. 40-55)
No. 7) Method using a solid wax at room temperature such as higher aliphatic carboxylic acid, higher aliphatic alcohol, paraffin, and polyethylene oxide (Japanese Patent Publication No. 43-272, Japanese Patent Publication No. 43-9955, and Japanese Patent Publication No. 44- 8907), polyalkylene oxide-modified silicon as a liquid at room temperature (Japanese Patent Publication No. 44-8907), cyclic amylsiloxane (Japanese Patent Publication No. 39-24858), and many other methods have been proposed.

However, these anti-sticking agents mainly having a releasing effect are not effective for sticking due to a chemical reaction due to an isocyanate group, which will be described later, and it cannot be said to be a sufficiently satisfactory method.

The sticking between yarns during spinning of polyurethane elastic yarns is not due to the rubber-like tackiness of polyurethane, but is generally said to be self-adhesive. Adhesion (allohanate bond and other chemical bond formation) occurs due to the reaction. As for the self-adhesive action, the more isocyanate groups are present on the surface of the polymer, the more the chemical reaction on the surface of the yarn proceeds, forming a stronger glue. Even for a bobbin that can unwind the yarn immediately after spinning, the self-adhesive action between the yarns progresses after several days, and the unwinding of the yarn becomes impossible, and in extreme cases, each layer of the yarn wound on the bobbin is plate-shaped. It will stick to the thread, and the thread will not be able to be pulled out at all.

In particular, this phenomenon is severe when producing a polyurethane elastic yarn by the melt spinning method, and in the method of mixing and spinning a prepolymer having an active isocyanate group at the end,
This tendency is remarkable, and a sufficient anti-sticking property cannot be obtained only by the above-mentioned releasing anti-sticking agent.

In order to prevent sticking of the isocyanate group due to a chemical reaction, it is necessary to deactivate the isocyanate group, and a method using a deactivator having an active hydrogen group has been proposed. As a method thereof, a method in which a mineral oil in which monoamine is already dissolved is applied at the time of spinning (Japanese Patent Publication No. 46-16).
No. 312), an oil containing a diamine (Japanese Patent Publication Sho 58).
-132170) is proposed.

This method is an effective method for deactivating the isocyanate group, but since the viscosity of the urethane polymer itself is low during melt spinning, or a low-viscosity prepolymer is mixed during spinning, it is If the polymer viscosity is lowered and the filament immediately after spinning is wound while it is still soft, gluing due to adhesion of polyurethane is strongly exhibited, and sufficient degluing resistance cannot be obtained only with the isocyanate group deactivator.

As an anti-sticking agent having both the releasability immediately after spinning and the effect of deactivating the active isocyanate group,
An oil agent that has already been combined with amino-modified silicone (Japanese Patent Publication No.
No. 8907) has been proposed.

In this method, even when the spun yarn is soft and a large amount of isocyanate groups are present at the time of melt spinning, the releasing effect of the dimethyl silicone chain and the loss of the isocyanate groups due to the active hydrogen of the amino groups are caused. It exhibits excellent anti-adhesion property due to its activity.

However, in the case of amino-modified silicone, which has a sufficient anti-sticking property, the fiber-to-fiber frictional force of the obtained yarn is extremely low, and when the bobbin is wound at the time of spinning and is rewound from the bobbin to another bobbin. Then, the rewound yarn will fall and collapse. Therefore, it is unavoidable to sacrifice the adhesive spinnability to some extent and to limit the use of amino-modified silicone which has no problem in the winding property.

As described above, various substances have been proposed as anti-sticking agents. Although a composition which is almost satisfactory only from the viewpoint of anti-sticking property has been proposed, an oil agent having no problem in actual use has not been found, including the operability of spinning and post-processing steps.

[0014]

DISCLOSURE OF THE INVENTION The present invention, when spinning a polyurethane elastic yarn by a melt-spinning method or the like, suppresses the sticking of the thread due to the active isocyanate group present on the surface of the thread and the increase in the sticking with time, and spinning and It is an object of the present invention to provide a method for producing a polyurethane capable of preventing the bobbin from falling and collapsing in the subsequent step and obtaining excellent operability in the subsequent step from spinning.

[0015]

[Means for Solving the Problems] In order to solve the above-mentioned problems, as a result of diligent studies on the composition of an oil agent to be applied at the time of spinning, when a urethane polymer is melt-spun, a general formula after solidification of a thread coming out of a die

Embedded image After applying a water-based emulsion containing a polyether amine represented by, after applying a non-aqueous oil agent,
The present invention has been reached by winding up.

In the polyetheramine used in the present invention, the active hydrogen of the amino group present in the molecule reacts with the active isocyanate group of the polyurethane exposed on the yarn surface to eliminate the reactivity, thereby producing an isocyanate. It is possible to suppress the occurrence of sticking due to the chemical reaction of the nato group.

The present invention is also effective for spinning urethane alone, but especially when a large amount of isocyanate groups are present on the yarn surface, such as when a prepolymer having an active isocyanate group is mixed and spun at the time of spinning. The effects of the present invention are well exhibited.

The polyurethane used in the composite fiber of the present invention may be any composition as long as it is a thermoplastic polyurethane that can be subjected to melt spinning. Further, in order to improve the stretchable property and heat resistant property of polyurethane, a product obtained by some modification during spinning, such as a product obtained by mixing spinning of a diisocyanate compound during spinning, can be similarly used.

As the polyol component constituting the thermoplastic polyurethane, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyether such as a copolymer of ethylene oxide and propylene oxide, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, Examples thereof include esters of a copolymer of ethylene oxide and propylene oxide and a dibasic acid such as adipic acid, poly ε-caprolactone, polyhexamethylene carbonate, and silicone polyol.

As the diisocyanate component, 4.
4'-diphenylmethane diisocyanate, 4.4'-
Examples thereof include dicyclohexylmethane diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate.

As the water-based oil agent of the present invention, which is applied when spinning the polyurethane elastic fiber, an aqueous solution in which only polyetheramine is dissolved may be used, or in order to increase the permeability of the aqueous solution in consideration of uniform adhesion to the yarn. A nonionic activator having a penetrating effect may be used in combination, or a commonly used oil agent mainly composed of mineral oil, fatty acid ester or dimethylsiloxane may be mixed and used in order to improve the smoothness of the yarn.

In order to exert the releasing effect of the polyetheramine, a high molecular weight polyetheramine is more effective, but 200 to 10,000 is used. If the molecular weight is less than 2000, the increase in sticking with time can be suppressed,
The releasing effect immediately after spinning is slightly weak, and when it exceeds 10,000, the viscosity of the aqueous solution applied during spinning becomes too high, the uniform adhesion to the yarn surface deteriorates, and sticking spinning unevenness occurs, which is not preferable.

Any weight ratio of polyethylene glycol and polypropylene glycol of the polyether amine can be used, but if the polypropylene glycol portion is too much, the water solubility of the polyether amine alone becomes poor, and the yarn is made into an aqueous solution at the time of spinning. It is difficult to use when giving. From the viewpoint of water solubility, polyethylene glycol is 40
% Or more of the polyether amine is easy to use, but other compositions can also be used if used as an emulsion in combination with a surfactant having excellent dispersibility.

The amount of polyetheramine applied to the yarn is appropriately set depending on the sticking condition of the spun yarn, but if the amount of polyallylamine added is too large, the smoothness of the yarn will deteriorate.
0.5% or less, preferably 0.3% or less is more preferable.

The amount of the polyetheramine aqueous solution applied to the yarn may be any level as long as water droplets do not ooze out onto the surface of the winding bobbin, but the limit is usually 20% by weight, and Accordingly, the concentration of the aqueous solution is appropriately determined so that the applied amount of polyallylamine is 0.5% or less.

Since the smoothness of the yarn is extremely poor only by adding the polyetheramine, it is essential to add the non-aqueous compounded oil agent in addition to the addition of the polyetheramine.

The non-aqueous compounded oil agent which is continuously applied to the water-based emulsion may be of any composition, but it is necessary to prevent the thread from winding around the roller due to the uniform adhesion to the thread and the viscous resistance of the oil agent during spinning. Therefore, the viscosity at 30 ℃ is 5
-50 CST or less is preferable.

When a lubricant oil such as mineral oil, fatty acid ester or dimethyl siloxane is used as the non-aqueous oil agent, if the viscosity is less than 5 CST, the oil agent has a high volatility and volatilizes and disappears from the yarn surface after spinning. Undesirably leads to a decrease in smoothness.

As a method for applying the oil agent to the yarn, a known method such as a spraying method, a roller surface contact method or an oil supply guide method can be used, but the oil supply guide method is the best in view of uniform adhesion to the thread.

[0030]

The present invention will be described in detail with reference to the following examples.
As a method for evaluating the effect of the present invention, unwinding tension which is a substitute property of anti-sticking property (immediately after spinning and after lapse of time), interfiber friction force which is a substitute property of collapse of a spinning bobbin or rewinding bobbin, and spinning bobbin winding The collapse situation was used.

Unwinding tension 1 m / mi from the spinning bobbin
At the take-up speed of n, the tension required to remove the thread from the bobbin surface when the thread is pulled out (refer to Fig. 1), and with this method, the average value of the maximum tension of 20 points per 5 m of thread length is unwound. Use tension. The measurement was performed immediately after spinning and after 7 days.

Frictional Force Between Fibers The spun yarns are combined so that the total denier becomes 400 denier, and the secondary tension is measured by the crossing method shown in FIG. (1) Temporary tension (initial tension) 1 gram (2) Number of yarn crossings 1 twist (360 degree rotation) (3) Yarn speed 2 cm / min (4) Measurement temperature and humidity 25 ° C, 65% RH

Spinning bobbin winding collapse When a contact pressure between the spinning friction roller and the winding bobbin is 500 g, a winding width of 80 mm (200 φ winding bobbin), a winding angle of 5 degrees, and a 40 denier yarn are wound at 500 m / min for 10 hours. The winding shape at that time is visually observed, and those without twill drop, collapse, and bottom yarn spread are considered good.

Polyetheramine can be produced by a method described in Experimental Chemistry Lecture Vol. 28, page 463, using methoxypolyol synthesized by using methanol as a reaction starting material as a raw material.

Example 1 Polytetramethylene glycol having a molecular weight of 1500 as a polyether and 4.4 'as a diisocyanate compound
-When diluting a thermoplastic polyurethane elastic body having a Shore hardness of 90 composed of diphenylmethane diisocyanate and 1.4-butanediol as a chain extender at 210 ° C and extruding with a screw extruder, before entering the spinneret, Poly (1.4-oxybutylene) with a molecular weight of 1500
15% by weight of diisocyanate was mixed with the polyurethane polymer, and the mixture was discharged from a 0.5 mm nozzle.
It was wound around a bobbin at 00 m / min to obtain a 40 denier monofilament.

Before being extruded from the spinneret and wound on the bobbin, the weight ratio of polyethylene glycol was 5%.
After applying 2% by weight of 0% of a polyetheramine having a molecular weight of 3500 dissolved therein, 2% was applied to the non-aqueous oil agent such as the oil agent A shown in Table 1 and the oil agent B shown in Table 2 and wound up.

[0037]

[Table 1]

[0038]

[Table 2]

As a comparative example of the present invention, as an example in which an aqueous solution of polyetheramine is not applied after spinning, oil agent A is used.
In the same manner, the yarn was sampled and evaluated in the case of using only the non-aqueous oil agent of B and the oil agent C of Table 3 and in the case of applying only the polyetheramine.

[0040]

[Table 3]

In each step of collecting these yarns, in order to judge the superiority or inferiority of the oil agent, the unwinding tension of the spinning bobbin, the inter-fiber frictional force, and the winding shape of the spinning bobbin were evaluated.
It shows in Table 5.

[0042]

[Table 4]

In the comparative example in which only the polyether amine was added, the smoothness of the yarn was poor, so that the frictional resistance with the yarn guides in the rewinding process was large and the yarn was frequently broken. Since the yarn of the present invention has excellent anti-sticking property and appropriate smoothness, the operation of the subsequent process was extremely successful.

[0044]

[Table 5]

Among the comparative oil agents which do not use polyetheramine, the oil agents A and B which do not have active hydrogen for deactivating the isocyanate group have a large increase in sticking with time and the unwinding property of the yarn at the time of rewinding is poor. There were many breaks, and the operability after the spinning process was poor. Further, although the oil agent C exhibited excellent anti-sticking property, the inter-fiber frictional force was too low, so that the bobbin collapsed during the winding of the fiber and it could not be wound for a predetermined time.

As described above, by using the polyether amine of the present invention, the spinning bobbin was not collapsed as compared with the case where this compound was not used, and the excellent anti-sticking property which was the main purpose was obtained.

[0047]

According to the method for producing a urethane elastic fiber of the present invention, since the spinning bobbin is less sticky and the winding shape of the spinning bobbin is excellent, the unwinding property and the winding shape in the subsequent process may be poor. High-quality urethane elastic fiber with less yarn breakage and excellent operability can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a method for measuring unwinding tension.

FIG. 2 is a diagram showing a method for measuring a frictional force between fibers.

Claims (1)

[Claims] 1. When melt-spinning a urethane polymer, the general formula: After applying a water-based emulsion containing a polyether amine represented by, after applying a non-aqueous oil agent,
A method for producing a urethane elastic fiber, which is characterized by winding.