JPH06287804A - Method for testing oil pickup on polyamide yarn - Google Patents

Abstract

PURPOSE:To accomplish an inexpensive testing method for oil pickup on polyamide yarns in high accuracy in a short time by measuring electrical resistance. CONSTITUTION:After a specified amount of polyamide yarns imparted with a lubricant is wound up, the yarns are held for 4hr or longer in an atmosphere at 15-35 deg.C at a RH of 30-80%. Then, the electrical resistance of the surface layer of the resultant polyamide yarn package is measured, and the oil pickup level on the polyamide yarns is tested using the measurement. Or, based on the data giving the relationship between the oil pickup and electrical resistance determined for the standard sample, the aimed oil pickup may be determined. Either testing method is preferably used when the lubricant is a water-based emulsion one >=75wt.% in water content. The above electrical resistance can be determined by measuring the electric current between the electrodes brought into contact with the surface layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting the amount of an oil agent attached to a polyamide yarn, which is used for inspecting the amount of the oil agent attached to the polyamide yarn during the production or processing of the polyamide yarn.

[0002]

2. Description of the Related Art In the process of manufacturing or processing polyamide yarn, an oil agent is added to the yarn to improve smoothness, antistatic property, abrasion resistance and the like. However, there is an appropriate range for the amount of oil agent adhesion due to its adaptability to higher-order processing of yarn and its effect on quality, and its management is a very important matter in terms of quality of polyamide yarn and management of manufacturing and processing process. It is said that. Conventionally, as an inspection method performed to control the amount of oil agent adhered to a polyamide yarn, a chemical inspection method in which an oil agent adhered using an organic solvent is extracted and measured, and a pair of running polyamide yarn to which an oil agent is applied is used. Contact the electrode of the and measure the electrical resistance,
A method of inspecting the amount of the oil agent attached to the polyamide yarn from the value (for example, the method described in JP-A-60-155709) has been used.

[0003]

However, in the above-mentioned chemical inspection method, the measuring time is very long, that is, 4 to 8 hours, and a solvent or the like is required, so that the cost is further increased. Also, the electric resistance of the running yarn is measured in the process,
The method for inspecting the amount of attached oil has a problem that it is difficult to measure the electric resistance with high accuracy because the yarn runs at high speed, and the moisture content tends to vary among the weights, resulting in poor reliability. . Then, the present inventor has completed the present invention as a result of researching a method for solving the above problems and inspecting the amount of the oil agent adhered to the polyamide yarn in a short time with high accuracy and at low cost.

[0004]

In order to achieve the above object, according to the present invention, after winding a predetermined amount of a polyamide yarn wound with an oil agent, the temperature is 15 to 35 ° C., and the relative humidity is 3.
After holding in an atmosphere of 0-80% for at least 4 hours,
Provided is a method for inspecting the amount of oil agent attached to a polyamide yarn, which comprises measuring the electrical resistance of the surface layer of a package of wound polyamide yarn and inspecting the level of the amount of oil agent attached to the polyamide yarn using the measured value. . Further, after winding a predetermined amount of polyamide yarn wound with an oil agent applied, the temperature is 1
After holding in an atmosphere of 5 to 35 ° C. and a relative humidity of 30 to 80% for at least 4 hours, the electrical resistance of the surface layer of the wound polyamide yarn package was measured, and the oil adhesion amount measured separately for the standard sample was measured. Provided is a method for inspecting the amount of oil agent attached to a polyamide yarn, wherein the amount of oil agent attached is determined based on data showing the relationship with the electric resistance, and the amount of oil agent attached to the polyamide yarn is inspected. The above inspection methods are preferably used when the oil agent is an aqueous emulsion oil agent having a water content of 75% or more, and the electric resistance of the surface layer is measured by measuring the current flowing between a pair of electrodes in contact with the surface layer. Is preferably measured.

[0005]

EXAMPLES AND OPERATION The method for inspecting the amount of the oil agent attached to the polyamide yarn of the present invention will be described in detail below with reference to the accompanying drawings. The present inventor has studied means for solving the problems of the conventional inspection method, and as a result, in a winding process of applying an oil agent to a yarn running at high speed, the electrical resistance of the running yarn is accurately measured accurately. It was found that there are many difficult problems to measure well and that the measured value of electric resistance tends to vary because the moisture content immediately after applying the oil agent is not stable. Therefore, the electrical resistance of the surface of a polyamide yarn package wound with an oil agent applied was measured, and the relationship with the oil agent adhesion amount of the polyamide yarn was compared. As a result, it has been found that the electrical resistance of the surface of the package has a high degree of correlation with the amount of the oil attached to the polyamide yarn. However, the measured electrical resistance is unstable over time, and as a result of further studies, the measured electrical resistance immediately after winding was greatly affected by the moisture content on the package surface, and the effect was It has been found that the moisture content of the package surface reaches an equilibrium state and stabilizes if the package is kept in a constant atmosphere for a predetermined time. That is, the package of polyamide yarn,
The electrical resistance measurement value is substantially stable if 4 hours or more have passed immediately after winding a predetermined amount in a constant atmosphere of 15 to 35 ° C. and a relative humidity of 30 to 80%.

The electric resistance can be easily measured by a contact type measuring device using a pair of flat plate type electrodes, and moreover, many samples can be processed in a short time. It's easy. For example, if a control limit value for the electric resistance is set, the level of the oil agent adhesion amount of the polyamide yarn can be known from the measured electric resistance value, and it can be easily inspected whether or not the oil agent adhesion amount is normal. . Furthermore, separately, data showing the relationship between the oil agent adhesion amount measured on a standard sample and the electric resistance, for example, a calibration curve and a conversion formula of both are obtained, and the oil agent adhesion amount is known from the measured value of the electric resistance. It is possible to easily inspect the amount of applied oil.

A specific embodiment of the present invention will be described. In a normal manufacturing process, a package of polyamide yarn rolled up by applying an oil agent is once put in an intermediate warehouse and then put into a 4-2
After 4 hours, each product is placed on the line, inspected as necessary, packed, and stored in the product warehouse. The atmosphere of the intermediate warehouse should be at least 1 temperature to maintain the quality of the product.
The relative humidity is adjusted to 5 to 35 ° C. and the relative humidity to 30 to 80%. Therefore, it is very convenient to provide an electric resistance measuring device in the flow of the package, and to carry out the above-mentioned inspection as well as the oil adhesion amount inspection of the polyamide yarn of the present invention. It is also easy to automate the measurement and automatically output a line out of a package whose electric resistance exceeds the required range before entering the product warehouse.

The example in which the amount of oil agent adhered is determined by the electric resistance of the package surface has been described above, but the present invention is not limited to this.
It can also be obtained by using a current flowing between a pair of electrodes or by utilizing the characteristic of electric resistance, for example, measurement by an electric resistance type moisture meter. Next, an example using a paper moisture meter (KG-40R type, manufactured by Sanko Electronic Laboratory Co., Ltd.) which is a DC electric resistance moisture meter will be described.

[0009]

EXAMPLE FIG. 1 shows how a flat plate type electrode 2 of a paper moisture meter 1 is brought into contact with the surface of a package 3 to perform measurement. In FIG. 2, the amount of the oil agent attached is at four levels, that is, 0.
For the packages A, B, C, and D that have been changed to 47, 0.41, 0.34, and 0.26 (%), the changes in the indicated value of the instrument from immediately after the predetermined amount of winding to 20 hours have been shown. It is a thing. As is clear from FIG. 2, the measured value of the instrument increases until 4 hours have passed immediately after winding,
Some are reduced and are unstable. However, after 4 hours, the moisture content on the package surface reaches an equilibrium state,
It can be seen that the meter readings are stable. The package was made by winding a polyamide yarn of 70 denier and 24 filaments, and the oil agent was an aqueous emulsion oil agent. The storage conditions of the package were a temperature of 27 ° C. and a relative humidity of 54%.

FIG. 3 shows the relationship between the amount of oil agent adhered to each package and the instrument indicated value after the lapse of 20 hours in FIG. As is apparent from FIG. 3, it is clear that there is a high correlation between the amount of deposited oil and the value indicated by the instrument. Further, as described above, it is possible to previously prepare a calibration curve for obtaining the amount of attached oil agent from the indicated value of the instrument. In the above inspection of the amount of applied oil, the time required for measurement with a paper moisture meter, including the recording time,
It was possible to measure 100 samples in a short time of 15 minutes / person on average.

[0011]

EFFECT OF THE INVENTION In the method for inspecting the amount of oil attached to a polyamide yarn according to the present invention, the electric resistance and the like are measured after the polyamide yarn is wound up and the moisture content of the package surface layer reaches an equilibrium state. The inspection result of can be obtained. Further, the present invention is achieved by measuring the surface of the package using an extremely simple device and can be carried out in a short time. Moreover, the inspection device of the present invention is provided during the transportation of the package and the automatic operation is possible. It is easy to do and the equipment cost is low.

[Brief description of drawings]

FIG. 1 is a schematic external view of a contact-type electric resistance type paper moisture meter using a flat plate type electrode.

FIG. 2 shows an example of changes over time in the indicated value of a paper moisture meter on the surface of a polyamide yarn package in a constant atmosphere.

FIG. 3 is a diagram showing a relationship between a paper moisture meter indicated value on the surface of a polyamide yarn package after 20 hours of winding and an oil agent adhesion amount.

[Explanation of symbols]

1: Electric resistance type paper moisture meter 2: Detection part (flat plate type electrode)
3: Package

Claims (4)

[Claims] 1. A polyamide yarn wound with an oil agent wound thereon, after being wound by a predetermined amount, at a temperature of 15 to 35 ° C. and a relative humidity of 3.
After holding in an atmosphere of 0-80% for at least 4 hours,
A method for inspecting the amount of oil agent attached to a polyamide yarn, which comprises measuring the electrical resistance of the surface layer of a package of wound polyamide yarn and using the measured value to inspect the level of the amount of oil agent attached to the polyamide yarn. 2. A polyamide yarn wound with an oil agent applied thereto is wound up by a predetermined amount, and then the temperature is 15 to 35 ° C. and the relative humidity is 3.
After holding in an atmosphere of 0-80% for at least 4 hours,
The electrical resistance of the surface layer of the wound polyamide yarn package was measured, and the amount of oil agent attached was calculated based on the data showing the relationship between the amount of oil agent attached and the electrical resistance measured separately for the standard sample. A method for inspecting the amount of oil agent attached to a polyamide yarn, which comprises inspecting the amount. 3. The oil agent according to claim 1, which is an aqueous emulsion oil agent having a water content of 75% or more.
A method for inspecting the amount of oil attached to a polyamide yarn as described above. 4. The adhesion of an oil agent to a polyamide yarn according to claim 1, 2 or 3, wherein the measurement of the electric resistance of the surface layer is a measurement of a current flowing between a pair of electrodes in contact with the surface layer. Quantity inspection method.