JPH10168645A - Production of synthetic fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out the uniform application of an oil agent without changing the process passableness with time by always sensing the oil agent concentration with an oil agent concentration sensor and performing the control so as to substantially maintain the control concentration. SOLUTION: A prescribed oil application treatment is carried out through an oil agent applying means 3 such as a lubrication roller type or a lubrication guide type in a process for quenching and solidifying a spun yarn Y discharged from a spinning part 1 with quench air and then taking off the solidified yarn with godet rollers 2. In the process, the oil agent concentration is always sensed with an oil agent concentration sensor 10 interposed between a circulating pump 7 of an oil agent circuit 20 for connecting a head tank 6 for feeding the oil agent to the oil agent applying means 3 to an oil agent storage tank 5 and the head tank 6, and opening and closing control of an opening and closing valve 9 of a pure water feeding pipe 8 is performed so as to maintain the range of 5-30% initially set control concentration ±5%. Thereby, the pure water supply to the storage tank 5 is regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing synthetic fibers, and more particularly to a method for producing synthetic fibers having excellent process passability by uniform application of an oil agent.

[0002]

2. Description of the Related Art Generally, in a spinning process such as a melt spinning process, an oil agent is applied to a spun yarn so that the processability in a raw yarn manufacturing process is improved, and a high-order processing process such as false twisting, twisting, knitting and weaving is performed. To improve the process passability. The adhesion amount of the oil agent is determined by the original yarn and the high-level processing step passability, and the appropriate value is determined by the properties of the oil agent and the type of yarn (fineness, number of single yarns, cross section, application, etc.). Also, as the oil agent applying means, an oil agent circulation circuit is configured from an oil agent storage tank and a head tank, and an oil film is formed on the surface by attaching an oil supply roll, an oil supply guide, and the like to the head tank,
Generally, the spun yarn is brought into contact with the refueling roll or refueling guide.

However, when the oil is repeatedly circulated through the oil circulation circuit, water gradually evaporates from the oil in the course of circulation, so that the temperature and concentration of the oil increase.
There is a phenomenon that the amount of the oil agent attached to the spun yarn also changes. For this reason, the amount of the oil agent attached to the spun yarn gradually deviates from the initially set value, and there is a problem that the processability deteriorates.

Conventionally, as a countermeasure against such a problem, the entire oil in the storage tank is replaced with a new oil at regular intervals. However, the operation of replacing the oil agent is not only complicated, but also has a problem that the spinning operation needs to be temporarily stopped during the replacement operation, thereby lowering the productivity.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, to make it possible to apply a uniform oil agent such that the processability does not change over time, and to improve the productivity. It is an object of the present invention to provide a method for producing a synthetic fiber.

[0006]

Means for Solving the Problems A method for producing a synthetic fiber according to the present invention is a method for producing a synthetic fiber in which an oil agent is added to a spun yarn in a spinning step. It is characterized in that it is maintained substantially constant at the set control density. In this way, since the concentration of the oil agent is maintained at a substantially constant control concentration while replenishing the oil agent with pure water, it is possible to uniformly apply the oil agent so that the processability does not change over time. Further, since there is no need to interrupt the operation as in the case where the entire amount of the oil agent is exchanged, the productivity can be improved.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The synthetic fibers applied to the present invention are not particularly limited as long as they are made from a fiber-forming synthetic polymer. For example, fibers such as polyester, polyamide, polyolefin, polyacryl, and polyvinyl alcohol can be used. Among these, polyester fibers containing ethylene terephthalate or butylene terephthalate as a main component and polyamide fibers containing nylon 6 or nylon 66 as a main component are particularly preferable.

The spinning step applied to the present invention can be applied to any of the spinning steps of melt spinning, dry spinning, wet spinning, and dry-wet spinning as long as an oil agent is imparted to the spun yarn. it can. Especially, it is most suitable for the melt spinning process. In the present invention, pure water to be replenished to the oil agent,
It refers to water whose electric resistance is increased to 100,000Ω or more by passing through an ion exchange resin or the like.

In the method for producing a synthetic fiber according to the present invention, when an oil agent is applied to the spun yarn in the spinning step, pure water is continuously added to the oil agent. Continuous is continuous,
It may be intermittent. The oil circulating in the oil circulation circuit is
Evaporates water over time, increasing temperature and concentration,
Since the pure water is added continuously or intermittently, the rise in temperature and concentration is suppressed, and the initially set control concentration can be maintained substantially constant.

[0010] By such an oil agent management, the amount of the oil agent attached to the produced yarn is kept constant, and the process passability based on the initially set control concentration can be maintained. In addition, by such continuous replenishment of pure water, it is not necessary to regularly replace the entire amount of the oil agent in the storage tank as in the related art, so that the yarn operability can be stabilized and the productivity can be improved. .

In the present invention, the control range in which the concentration of the oil agent is kept substantially constant while replenishing pure water is preferably within a range of ± 0.5% of the specified control concentration. Also,
The control concentration is preferably in the range of 5 to 30%. Further, since pure water is continuously supplied, in the present invention, it is only necessary to first prepare an oil agent having a concentration exceeding the above-mentioned control concentration as the first oil agent to be put in the oil agent storage tank.

The production method of the present invention has a spinning speed of 10
When applied in the range of 00 to 6000 m / min, more remarkable effects can be obtained. FIG. 1 is a schematic diagram showing a melt spinning step used in the method for producing a synthetic fiber of the present invention. Reference numeral 1 denotes a spinning unit of a melt spinning machine (not shown). The spun yarn Y discharged from the spinning unit 1 is cooled by cooling air and then taken up by a godet roller 2. Oil agent is given. The spun yarn Y drawn by the godet roller 2 is stretched as necessary and wound up on a bobbin 4 mounted on a winder.

The oil applying means 3 is only required to apply an oil to the surface of the spun yarn, and is composed of, for example, an oil supply roller and an oil supply guide. Alternatively, a means for metering and refueling with a metering pump may be used. The oil agent is generally applied to the spun yarn in a state of being dissolved in water or diluted as an emulsion. On the other hand, the oil agent circulation circuit 20 is configured by connecting the storage tank 5, the head tank 6, and the circulation pump 7 in a loop. The circulation pump 7 pumps up the oil agent in the storage tank 5 and supplies it to the head tank 6, and then returns the oil agent from the head tank 6 to the storage tank 5 again. The oil supply means 3 is attached to the head tank 6, and this head tank 6 supplies a fixed amount of the oil supplied from the circulation pump 7 to the oil supply means 3, and overflows and stores the remaining excess. The liquid is returned to the tank 5.

A pure water supply pipe 8 is connected to the storage tank 5 via an electromagnetic on-off valve 9. In the oil circulation circuit 20, an oil concentration detector 10 is connected between the circulation pump 7 and the head tank 6. The oil concentration detector 10 constantly monitors and detects the oil concentration, and when the oil concentration deviates from the prescribed control concentration by ± 0.5%,
A valve opening command is issued to the opening / closing valve 9 to supply pure water to the storage tank 5 so that the concentration of the oil agent is always maintained within the range of the control concentration ± 0.5%.

As the oil agent concentration detector in the present invention,
Although not particularly limited, since the concentration of the oil agent and the refractive index are in a proportional relationship, it can be easily constituted by a refractometer. Hereinafter, the examples will be described. The concentration of the oil in the examples is determined by measuring the refractive index with a refractometer for several types of oils whose concentrations are known in advance, and using the values of the refractive index and the known concentration. It is obtained by converting the refractive index into a concentration by the obtained calibration curve. The amount of oil adhering to the spun yarn was measured by a method for measuring the amount of solvent extractables according to JIS L1013-1981.

[0016]

EXAMPLE A polyester mainly composed of ethylene terephthalate was melt-spun at a take-off speed of 3,500 m / min, and a 10% emulsion mainly composed of polyether was used as an oil agent to reduce the oil adhesion to 0.5%. In producing a yarn of 240 denier and 48 filaments,
The control concentration of the oil agent was 10.0%, pure water was continuously added to the oil agent, and the applied amount (cc / min) was varied as shown in Table 1, and used continuously for one day for each of the five levels. The change in the concentration of the oil agent and the fuzz and dye unevenness of the corresponding yarn were measured. In addition, the dyeing unevenness was judged by an expert by visual observation, good was evaluated as ○, slightly good as Δ, and poor as ×.
It was expressed by. The results are shown in Table 1.

[0017] From Table 1, it can be seen that No. 1 (conventional example)
After 1 day, the concentration of the oil agent increased by 2%, and fluff and uneven dyeing were remarkably observed.

No. 1 in which pure water was continuously supplied. In Examples 2 to 5, the increase in the concentration of the oil agent was suppressed and maintained substantially constant, and the fluff and uneven dyeing could be reduced. In particular, in the case of No. 1 which was in the range of ± 0.5% with respect to the control concentration of 10.0%. 4 and No. With No. 5, fluff generation and uneven dyeing were further reduced.

[0019]

As described above, according to the present invention, since the concentration of the oil agent is kept substantially constant at the control concentration while replenishing the oil agent with pure water, the uniformity of the process passage with time does not change. Oil agent can be applied. In addition, since there is no need to interrupt the operation as in the case of replacing the entire amount of the conventional oil agent, productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a melt spinning step used in a method for producing a synthetic fiber of the present invention, together with an oil applying device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spinning part 3 Oil supply means 5 Storage tank 6 Head tank 7 Circulation pump 8 Pure water supply pipe 9 On-off valve 10 Oil concentration detector 20 Oil circulation circuit

Claims (4)

[Claims] 1. A method for producing a synthetic fiber in which an oil agent is added to a spun yarn in a spinning step, wherein the oil agent concentration is maintained substantially constant at an initially set control concentration while supplying pure water to the oil agent. Production method. 2. The oil agent concentration is set to ± 0.5 of the control concentration.
%. The method for producing a synthetic fiber according to claim 1, wherein the ratio is maintained in the range of%. 3. The method for producing a synthetic fiber according to claim 1, wherein the control concentration is 5 to 30%. 4. An oil agent circulation circuit is formed by connecting an oil agent storage tank and a head tank, and an oil agent concentration detector and a pure water supply pipe are attached to the oil agent circulation circuit, and the oil agent concentration detected by the oil agent concentration detector is provided. The synthetic fiber production method according to claim 1, 2 or 3, wherein pure water is supplied from the pure water supply pipe to maintain the concentration of the oil agent substantially constant at an initially set control concentration.