JPH08110820A - Method and device for automatically preparing alkali solution for caustic reduction processing of polyester-based fabric - Google Patents

Abstract

PURPOSE: To provide a method and device for automatic preparation alkali solution for amount reduction processing which accurately performs the amount reduction processing of polyester-based fabric to a desired caustic reduction rate. CONSTITUTION: Alkali solution is prepared in a mixing tank 1. The mixing tank 1 is provided with a circulation path 5, and a concentration detecting means 9 is provided at an optional position in the circulation path 5 and compares the detected concentration with a set concentration to detect the concentration difference. The amount of a high-concentration alkali solution and/or the amount of water which is deficient is calculated from the concentration difference and the concentration of the high- concentration alkali solution fed to the mixing tank 1 and the set concentration. Then, the solution or water is fed to the mixing tank 1 by the calculated amount. The calculation is automatically made by a computer following a preprogrammed procedure. Consequently, the concentration of the alkali solution in the mixing tank 1 is held constant at all times. The alkali solution discharged from the exit of the mixing tank 1 is supplied to a dipping tank 3 to perform the caustic reduction processing of the polyester-based fabric 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for automatically preparing an alkaline aqueous solution for accurately reducing the weight of a polyester cloth composed of polyester fibers.

[0002]

2. Description of the Related Art It has long been practiced to reduce the weight of polyester cloth by treating it with an aqueous alkali solution such as an aqueous solution of caustic soda. By reducing the weight of the polyester-based cloth, it is possible to obtain the effects of expressing flexibility similar to silk, reducing static electricity generation, preventing pilling, and improving antifouling property. The degree of such an effect varies depending on the weight reduction rate at the time of weight reduction processing. Therefore, if it is intended to improve the desired physical properties, it is necessary to carry out weight reduction processing so that the weight reduction rate becomes constant.

For this reason, conventionally, various methods have been adopted as methods for performing weight reduction processing so that a constant weight reduction rate is achieved. For example, a plurality of polyester cloths for weight reduction processing and a plurality of test cloths identical to the polyester cloths are immersed in a treatment bath filled with an aqueous alkaline solution, and after a certain period of time, the test cloths are sequentially taken out, and the test cloths A method is adopted in which the weight reduction processing is terminated when the test cloth reaches a desired weight loss rate while measuring the weight loss rate. However, in this method, while the weight reduction rate of the test cloth is being measured, the weight reduction processing of the polyester cloth is in progress, so the weight reduction processing with the same weight reduction rate as that of the test cloth is performed. Was difficult. Therefore, in this method, it was extremely difficult to process the polyester-based fabric so as to have a desired weight loss rate.

Further, a polyester cloth to be processed for weight reduction is dipped in a treatment bath filled with an alkali aqueous solution, and after a certain period of time, a decrease in concentration of the alkali aqueous solution in the treatment bath is measured, and a weight reduction rate is calculated from this value. However, a method of terminating the weight reduction processing when the desired weight reduction rate is reached is also adopted. Furthermore, in this case, instead of measuring the decrease in the concentration of the alkaline aqueous solution, measuring the concentration of the hydrolysis product formed in the treatment bath is also adopted (Japanese Patent Publication No. 4-2446). This method is superior to the above method using a test cloth in that it can be adjusted to achieve a desired weight loss rate. However, this method can be used when batch-processing the weight reduction processing of polyester-based fabric,
It has a drawback that it cannot be used for weight reduction processing (online weight reduction processing) of continuously running polyester-based fabrics. Further, the measurement of the decrease in the concentration of the alkaline aqueous solution and the measurement of the hydrolysis product are complicated, and it cannot be said that it is a simple method.

[0005]

Therefore, according to the present invention, the weight loss rate becomes constant when the polyester cloth is impregnated with a constant amount of the alkaline aqueous solution and the hydrolysis reaction is performed under the constant condition. Focusing on the points, based on this,
By providing a method and an apparatus capable of constantly and automatically adjusting the concentration of an alkaline aqueous solution with which a polyester-based fabric is impregnated, it is intended to enable a continuous running polyester-based fabric to be weight-reduced at a constant weight-reduction rate. It is a thing.

[0006]

That is, according to the present invention, a preparation tank for preparing an alkaline aqueous solution, an alkali storage tank for supplying a high-concentration alkaline aqueous solution to the preparation tank, and water for the preparation tank. Water input means for
A method for automatically preparing an alkaline aqueous solution for weight-reducing a polyester-based fabric by using a circulation path for circulating the alkaline aqueous solution in the mixing tank from an outlet of the mixing tank to an inlet of the mixing tank. Of the alkaline aqueous solution is circulated to circulate in the circulation path, the concentration of the arbitrary alkaline aqueous solution is measured, and then the concentration and the concentration of the high-concentration alkaline aqueous solution previously stored in the storage device and the set concentration to be prepared From the above, the amount of high-concentration alkaline aqueous solution and / or the amount of water for achieving the set concentration is calculated, and the calculated amount is added to the blending tank from the alkali storage tank and / or the water charging means. The present invention relates to a method for automatically preparing an alkaline aqueous solution for weight reduction processing.

Further, according to the present invention, there is provided a preparation tank for preparing an alkaline aqueous solution, an alkali storage tank for introducing a high-concentration alkaline aqueous solution into the preparation tank, and a water introducing means for introducing water into the preparation tank. A concentration detecting means for detecting the concentration of the alkaline aqueous solution present in the circulation passage, the circulation passage circulating the alkali aqueous solution in the preparation tank from the outlet to the inlet of the preparation tank; A concentration difference detecting means for comparing the concentration detected by the detecting means with a set concentration and detecting a concentration difference; and a calculating means for calculating an insufficient high-concentration alkaline aqueous solution amount and / or water amount based on the concentration difference. The insufficient high-concentration alkaline aqueous solution amount and / or water amount calculated by the calculating means was charged into the blending tank from the alkali storage tank and / or the water charging means. It relates reduction processing for an alkaline aqueous automatic blender polyester fabric which is characterized by comprising the adjustment means.

Hereinafter, FIG. 1 showing a weight reduction processing apparatus for a polyester cloth according to an example of the present invention, a block diagram showing a procedure of an automatic alkaline aqueous solution mixing method (FIG. 2) and a block diagram showing means of the apparatus (FIG. The present invention will be described based on 3).

Reference numeral 1 is a mixing tank for adjusting the alkaline aqueous solution to a predetermined concentration. As the alkaline aqueous solution, an aqueous solution prepared by diluting a basic substance such as caustic soda, caustic potash and sodium silicate with water is used. In particular, it is preferable to use an inexpensive caustic soda aqueous solution.
The concentration of such an alkaline aqueous solution is generally 5 to 3
Although it is about 0% by weight, in order to achieve a desired weight reduction rate, the concentration may be lower or higher than this concentration.
As an initial method of adjusting the alkaline aqueous solution, the alkaline substance (basic substance) and water may be separately charged into the mixing tank 1 and stirred and dissolved in the mixing tank 1 to adjust the alkaline aqueous solution. Then, a high-concentration alkaline aqueous solution in which an alkaline substance is dissolved in a high concentration and water are separately charged, and the alkaline aqueous solution may be adjusted by stirring in the blending tank 1, or a previously adjusted alkaline aqueous solution may be blended. You may throw in in the tank 1. In any case, it is preferable that the mixing tank 1 is provided with the heater 11 so that the alkaline substance is not deposited. Heater 11
For this, it is preferable to employ a steam heater using steam as the heating medium.

The mixing tank 1 is provided with a circulation path 5 for measuring the concentration of the alkaline aqueous solution. In the circulation path 5, the alkaline aqueous solution flows from the outlet of the preparation tank 1 toward the inlet. The alkaline aqueous solution is caused to flow in such a direction in order to measure the concentration of the alkaline aqueous solution flowing out from the preparation tank 1. Further, in order to flow the alkaline aqueous solution in such a direction, the circulation pump 15 provided in the circulation path 5 may be used. And circuit 5
The density detecting means 9 is provided at any position.

As the concentration detecting means 9, various conventionally known devices are used, but in the present invention, it is particularly preferable to employ the concentration detecting means 9 using a density meter. A densitometer measures the density of an alkaline aqueous solution,
The concentration is detected, and the concentration can be measured relatively accurately. For example, between the density and the concentration of an alkaline aqueous solution represented by a caustic soda aqueous solution, Y = a
X + b [where Y is the density of the alkaline aqueous solution (g / cm ³ )
Where a is a coefficient, X is the concentration (% by weight) of the alkaline aqueous solution, and b is a correction value. ], The concentration of the alkaline aqueous solution is detected using this equation. The density is calculated from the density automatically according to a pre-programmed procedure. Next, when the concentration of the alkaline aqueous solution is detected, this concentration is compared with the set concentration to detect the concentration difference. The set concentration is stored in a storage device (memory) in advance, and the difference between the detected concentration and the stored set concentration is detected by a preprogrammed procedure. After detecting the concentration difference,
It is calculated how much high-concentration aqueous alkaline solution is needed or how much water is needed to reach the set concentration. This calculation is performed by a preprogrammed procedure based on the set concentration and the concentration of the high-concentration alkaline aqueous solution stored in advance in the memory. Then, when the amount and / or water amount of the high-concentration alkaline aqueous solution is calculated, this calculated amount is put into the blending tank from the alkali storage tank 23 and / or the water feeding means 24. The calculated amount is input by opening and closing an adjusting means (for example, a valve) provided in the alkali storage tank 23 or the water adding means 24 for a predetermined time. In addition, the water charging means 2
As 4 there may be used a commonly used tap water or a tank storing water.

The above-described automatic method for preparing an alkaline aqueous solution will be described below with reference to the block diagram shown in FIG. First, concentration detecting means (for example, a densitometer and a concentration calculating program) provided in the circulation path 5
The concentration (a) measured in 9 is input to P. Also,
The preset density (b) stored in advance is input to P. Then, the program in P detects the density difference. Next, the alkali storage tank 2 stored in advance
The concentration (c) of the high-concentration alkaline aqueous solution present in 3 is P
Is input to Then, based on the obtained difference in concentration and the concentration of the high-concentration alkaline aqueous solution, a required amount (that is, insufficient) high-concentration alkaline aqueous solution and / or a required amount (that is, insufficient) water are determined by the program in P. Is calculated. Then, the calculated amount (d) is output, and the adjusting means such as a valve provided in the alkali storage tank 23 and / or the water charging means 24 is opened for a predetermined time, and a required amount of the high-concentration alkaline aqueous solution and / Or water is added. In this description, the set density (b)
The concentration (c) of the high-concentration alkaline aqueous solution is stored in a storage device different from P and is input to P from there, but it may be stored directly in the program of P. Needless to say.

The above-described automatic mixing method of the alkaline aqueous solution can be expressed as a combination of function realizing means as shown in the block diagram of FIG. That is, the concentration detecting means A measured in the circulation path 5, the concentration difference detecting means B for detecting a concentration difference using the detected concentration and the set concentration, and the concentration difference and the high concentration alkaline aqueous solution. Consistency of concentration and a calculation means (C) for calculating a necessary amount (that is, deficiency) of a high-concentration alkaline aqueous solution and a necessary amount (that is, deficiency) of water to achieve a set concentration. It is a thing. Further, the density difference detecting means B has
A memory for storing the set concentration may be attached, or the calculating means C may be attached with a memory for storing the concentration of the highly concentrated alkaline aqueous solution. The density difference detecting means B itself stores the set density, and the calculating means C
If the high concentration alkaline aqueous solution concentration is stored in itself,
It goes without saying that these memories are unnecessary.

According to such an automatic blending method, when the concentration of the alkaline aqueous solution is higher than a desired value, water is added to the blending tank 1, while when the concentration is low, a high-concentration alkaline such as caustic soda is used. The aqueous solution is put into the preparation tank. When the concentration is measured by measuring the density of the alkaline aqueous solution, the temperature of the density changes the relationship between the density and the concentration. It is preferable to keep the temperature at 40 ± 1 ° C).
That is, the heater 11 provided in the mixing tank 1 plays a role of improving the solubility of the alkaline substance in the alkaline aqueous solution and a role of maintaining the temperature of the alkaline aqueous solution constant. As described above, in the mixing tank 1, the alkaline aqueous solution having a constant concentration is constantly adjusted.

The alkaline aqueous solution discharged from the outlet of the mixing tank 1 partially flows into the circulation path 5, but mostly flows into the liquid supply path 6. A liquid feed pump 16 is provided at an arbitrary position in the liquid feed path 6, and the alkaline aqueous solution flows into the immersion tank 3 into which the liquid feed path 6 is introduced. At this time, it is preferable to provide the storage tank 2 in the middle of the liquid supply path 6 and store the alkaline aqueous solution in the storage tank 2. The reason for this is that if there is a storage tank 2,
This is because the alkaline aqueous solution can be continuously fed to the dipping tank 3 even when the alkaline aqueous solution runs out in the mixing tank 1. It should be noted that the storage tank 2 also has a heater 1
It is preferable to attach 2 to prevent the alkaline substance from precipitating or to prevent the alkaline aqueous solution from being heated too much in the immersion tank 3. As the heater 12, it is preferable to adopt a steam heater using steam as a heating medium.

The alkaline aqueous solution is fed into the dipping tank 3 through the liquid feeding path 6 to fill the dipping tank 3 with the alkaline aqueous solution. Then, the polyester cloth 22 which continuously runs is dipped in this alkaline aqueous solution and allowed to pass therethrough. The running speed of the polyester cloth 22 that continuously runs is generally 30 m / min or more, but preferably 50 to 50
60m / min is good. In this way, the polyester cloth 22 is impregnated with the alkaline aqueous solution.
This impregnation amount is 25-
It is preferably 70% by weight. Further, it is preferable that a heater 13 is also attached to the immersion tank 3 so that the alkaline substance is not deposited. As the heater 13, it is preferable to adopt a steam heater using steam as a heating medium. In addition, the dipping tank 3 is heated by the heater 13.
The temperature of the alkaline aqueous solution therein is generally maintained at about 40 ° C., which is similar to the temperature in the mixing tank 1. This is to maintain the accuracy of the set weight loss rate, but usually 30 ° C. or higher is acceptable.

It is preferable that the immersion tank 3 is provided with a recovery passage 7 to recover the alkaline aqueous solution overflowing from the immersion tank 3. Further, the alkaline aqueous solution overflowing from the storage tank 2 may be simultaneously recovered in the recovery passage 7. Then, the recovery pump 17 recovers the alkaline aqueous solution in the recovery tank 4. The alkaline aqueous solution recovered in the recovery tank 4 is filtered through impurities and the like, and then returned to the mixing tank 1 through the liquid delivery recovery path 8. A liquid feed pump 18 is provided in the liquid feed recovery path 8, and the pump 18 returns the alkaline aqueous solution that has been favorably recovered to the mixing tank 1.

On the other hand, the polyester cloth 22 impregnated with the alkaline aqueous solution is subsequently introduced into the steamer 10. And, the polyester cloth 22 is generally 90 ° C.
It is heated to the above temperature. If the heating temperature is lower than 90 ° C., the polyester fibers constituting the polyester cloth 22 will not be sufficiently hydrolyzed. The time for introducing the polyester cloth 22 into the steamer 10, that is, the reaction time for hydrolysis is sufficient if it is 1 minute or more, preferably about 6 to 10 minutes. Thus, the polyester cloth 22 impregnated with the alkaline aqueous solution
Is introduced into the steamer 10 to reduce the weight.

When the steamer 10 is subjected to the weight reduction process, the hydrolysis product is attached to the polyester cloth 22. The product of hydrolysis is primarily sodium terephthalate. In order to remove this product from the polyester-based cloth 22, the polyester-based cloth 22 is introduced into the water washing machine 21 after the treatment with the steamer 10. The washing with the water washing machine 21 may be carried out to the extent that no hydrolysis product remains on the polyester cloth 22. When the hydrolysis product remains on the polyester cloth 22, the dyeability, flexibility, antifouling property, etc. of the polyester cloth 22 tend not to be sufficiently improved.

By using the method for automatically preparing an alkaline aqueous solution or the apparatus for automatically preparing an alkaline aqueous solution according to the present invention, it is possible to continuously or intermittently pour an alkaline aqueous solution having a constant concentration into the dipping tank 3. Then, the alkaline aqueous solution overflowing from the dipping tank 3 can be recovered through the recovery path 7. Therefore, the alkaline aqueous solution in the immersion tank 3 can always be maintained at a constant concentration. That is,
By using the method or apparatus according to the present invention and continuously or intermittently pouring an alkaline aqueous solution of a constant concentration into the immersion tank 3, while continuously maintaining the concentration of the alkaline aqueous solution in the immersion tank 3, It is possible to adopt the method for reducing the weight of the running polyester-based fabric 22.

If the temperature at which the polyester cloth 22 is heated in the steamer 10 and / or the time for the polyester cloth 22 to pass through the steamer 10 are determined, only the concentration of the alkaline aqueous solution with which the polyester cloth 22 is impregnated is determined. By changing it, the weight loss rate can be changed. That is, by changing only the concentration of the alkaline aqueous solution, it is possible to adopt a method of reducing the weight of the polyester cloth 22 at various weight reduction rates.

[0022]

【Example】

Example 1 302 liters of water and 700 liters of a 28.5% by weight caustic soda aqueous solution were added to a compounding tank, and the temperature of the solution was adjusted to 40 by a heater.
While maintaining the temperature at ± 1 ° C, stirring and dissolution were performed to prepare an alkaline aqueous solution (caustic soda aqueous solution). This alkaline aqueous solution was passed through a circulation path, its density was measured with a densitometer, and its concentration was calculated by a program prepared in advance. As a result, the concentration was 21.9% by weight. Using this concentration as the set concentration, the computer was operated so that it always became the set concentration. Next, this alkaline aqueous solution was sent to a storage tank, and the temperature of the solution was maintained at 40 ± 1 ° C. by a heater provided in the storage tank. Then, the alkaline aqueous solution was continuously fed from the storage tank to the immersion tank, and the temperature of the alkaline aqueous solution in the tank was maintained at 40 ± 2 ° C. by the heater provided in the immersion tank.

Then, a polyester cloth (woven fabric woven with 75 denier polyester multifilaments) continuously running at a speed of 50 m / min was passed while being dipped in an alkaline aqueous solution in a dipping tank. Then, the continuously running polyester cloth was introduced into the steamer whose ambient temperature was kept at 115 ° C., and the hydrolysis reaction was carried out for a reaction time of 6 minutes. Subsequently, while the polyester cloth was continuously running, it was introduced into a water washing machine and washed with water to remove a hydrolysis reaction product. When the weight reduction rate of the polyester cloth subjected to the weight reduction processing as described above was calculated, it was 18.2% by weight while the target weight reduction rate was 18% by weight. In addition, when weight reduction processing was performed by this method continuously for 24 hours and 30 samples were collected and the weight reduction rate of each sample was measured, the variation of the weight reduction rate was 1%.

Comparative Example 1 An alkaline aqueous solution was prepared by placing 44 g / liter of a caustic soda aqueous solution in a 5500 liter treatment bath. And
Into this alkaline aqueous solution, the same 30-piece polyester cloth as that used in Example 1 was dipped. Then, the weight reduction processing was performed at a processing temperature of 98 ° C. for a processing time of 58 minutes. Then, when the concentration of the alkaline aqueous solution in the treatment bath reached 40 g / liter, cooling was started to terminate the reaction.
The concentration of the alkaline aqueous solution after cooling was 39.3 g / liter. When the weight reduction rate of the polyester fabric subjected to the weight reduction processing as described above was determined, it was 17.3 weight% while the target weight loss rate was 18 weight%. Also, in 24 hours
Five batches of weight reduction processing were performed, samples of each batch were collected, and the weight reduction rate of each was measured. As a result, the variation of the weight reduction rate was 1.5%.

As is clear from a comparison between Example 1 and Comparative Example 1, the method according to Example 1 is reduced in weight loss at a weight reduction rate closer to the target weight reduction rate than in the method according to Comparative Example 1. Processing can be performed. In the method according to Comparative Example 1, even if an attempt is made to start cooling to end the reaction,
The reaction does not end immediately. This is clear from the fact that the concentration of the alkaline aqueous solution at the start of cooling does not match the concentration of the alkaline aqueous solution after the completion of cooling. Therefore, the cooling cannot be started after the concentration of the alkaline aqueous solution reaches the target value, and the cooling must be started after predicting the concentration after the cooling to some extent.
Therefore, it becomes difficult to obtain a weight loss rate that is close to the target weight loss rate in the part that depends on this prediction. Also,
In the method according to Example 1, the fluctuation rate of the weight reduction rate is small even after continuous operation for 24 hours, while the method according to Comparative Example 1
It can be seen that the fluctuation rate of the weight loss rate increases when operated for 24 hours.

Example 2 Alkaline aqueous solution (caustic soda aqueous solution) measured in a circulation path
The concentration is 12% by weight, and a mixed fiber woven fabric of 50% by weight of polyester fiber and 50% by weight of nylon fiber is used as the polyester-based cloth. I went. Then, 30 samples of the obtained polyester cloth were sampled, and the weight loss rate of each sample was measured. The average value of this weight loss rate is the target weight loss rate.
It was 7.9% by weight with respect to 8% by weight. The change in weight loss rate was 0.6%.

Example 3 Alkaline aqueous solution (caustic soda aqueous solution) measured in a circulation path
The weight reduction treatment was carried out in the same manner as in Example 2 except that the concentration was 16% by weight. Then, the weight loss rate and the variation in the weight loss rate were measured by the same method as in Example 2. As a result, the weight loss rate was 10.8 wt% against the target weight loss rate of 11 wt%.
Met. The change in weight loss rate was 0.8%.

As is clear from the weight reduction processing methods according to Examples 2 and 3, the concentration of the alkaline aqueous solution should be changed while the steamer conditions, that is, the hydrolysis reaction temperature and the hydrolysis reaction time conditions are kept constant. Thus, the weight reduction rate can be changed to a desired value, and the polyester fabric can be weight-reduced.

[0029]

[Effects of the Invention] When the polyester cloth is subjected to the weight reduction processing by using the alkaline aqueous solution automatic blending method or the alkaline aqueous solution automatic blending apparatus according to the present invention, the concentration is always automatically kept constant in the blending tank. The aqueous alkaline solution is flowing into the dipping tank, the polyester cloth is dipped in the alkaline aqueous solution in this dipping tank, and the polyester cloth impregnated with a certain amount of the alkaline aqueous solution is introduced into the steamer to form the polyester cloth. The polyester fiber that is being processed is hydrolyzed to be processed for weight reduction. Therefore, since the concentration of the alkaline aqueous solution is maintained constant, there is an effect that the weight reduction processing can be easily performed so as to achieve the target weight reduction rate.

Further, when the concentration is measured in the mixing tank by measuring the density of the alkaline aqueous solution poured into the circulation path, the concentration can be accurately measured. Further, since the concentration can be accurately measured, there is an effect that the concentration of the alkaline aqueous solution in the preparation tank can be automatically and quickly kept constant.

Further, since the method for automatically preparing an alkaline aqueous solution or the apparatus therefor according to the present invention can be adopted even when the polyester cloth is continuously running, the productivity of the weight reduction processing of the polyester cloth is greatly improved. The effect that it can be improved.

Further, in the method for automatically preparing an alkaline aqueous solution according to the present invention, when a recovery passage for collecting the alkaline aqueous solution discharged from the dipping tank and returning it to the mixing tank is provided, the excess alkaline aqueous solution is re-used. It is possible to utilize, and it is possible to rationalize the weight reduction processing of the polyester cloth.

[Brief description of drawings]

FIG. 1 is a schematic view of a weight reduction processing apparatus equipped with an automatic alkaline aqueous solution mixing device for polyester cloth according to an example of the present invention.

FIG. 2 is a block diagram showing a procedure of an alkaline aqueous solution automatic preparation method according to an example of the present invention.

FIG. 3 is a block diagram showing a means of an alkaline aqueous solution automatic blending device according to an example of the present invention.

[Explanation of symbols]

1 Preparation Tank 2 Storage Tank 3 Immersion Tank 4 Collection Tank 5 Circulation Path 6 Liquid Delivery Path 7 Recovery Path 8 Liquid Delivery Recovery Path 9 Concentration Detection Means 10 Steamer 11 Heater 12 Heater 13 Heater 15 Circulation Pump 16 Liquid Feed Pump 17 Recovery pump 18 Liquid feed pump 21 Water washer 22 Polyester cloth 23 Alkaline storage tank 24 Water input means P Program for automatic preparation of alkaline aqueous solution a Concentration of measured alkaline aqueous solution b Set concentration c Concentration of highly concentrated alkaline aqueous solution d Calculated amount of highly concentrated alkaline aqueous solution and / or water A Concentration detecting means of alkaline aqueous solution B Concentration difference detection means between set concentration and measured concentration C Calculating means of required amount of highly concentrated alkaline aqueous solution and / or water D Set concentration Memory for storing E Memory for storing the concentration of high-concentration alkaline aqueous solution

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiharu Yamatani, 377, Minato-cho, Mikawa-cho, Ishikawa-gun, Ishikawa Prefecture (72) Intex Co., Ltd. (72) Noriyuki Imai 2-15-24, Izumigaoka, Kanazawa, Ishikawa Prefecture Mutual Electricity Within the corporation

Claims (4)

[Claims] 1. A preparation tank for preparing an alkaline aqueous solution, an alkali storage tank for introducing a high-concentration alkaline aqueous solution into the preparation tank, a water introduction means for introducing water into the preparation tank, and the preparation tank. A method for automatically preparing an alkaline aqueous solution for weight reduction processing of a polyester-based fabric by using a circulation path for circulating the alkaline aqueous solution therein from an outlet of the blending tank to an inlet, wherein an arbitrary alkaline aqueous solution is added to the blending tank. To circulate the circuit,
The concentration of the arbitrary alkaline aqueous solution is measured, and then, based on the concentration, the concentration of the high-concentration alkaline aqueous solution stored in advance in the storage device, and the set concentration to be prepared, the amount of the high-concentration alkaline aqueous solution for achieving the set concentration. And / or an amount of water is calculated, and the calculated amount is added to the mixing tank from an alkali storage tank and / or a water charging means. 2. The method for automatically preparing an alkaline aqueous solution for weight reduction processing of a polyester cloth according to claim 2, wherein an alkaline aqueous solution which has been used and recovered is used as an arbitrary alkaline aqueous solution. 3. A preparation tank for preparing an alkaline aqueous solution, an alkali storage tank for introducing a high-concentration alkaline aqueous solution into the preparation tank, a water introduction means for introducing water into the preparation tank, and the preparation tank. A concentration detecting means for detecting the concentration of the alkaline aqueous solution present in the circulation path, and a circulation path for circulating the alkaline aqueous solution therein from the outlet to the inlet of the preparation tank; Concentration difference detecting means for comparing the determined concentration and the set concentration to detect a concentration difference, a calculating means for calculating an insufficient high-concentration alkaline aqueous solution amount and / or a water amount based on the concentration difference, and the calculating means And an adjusting means for charging the insufficient high-concentration alkaline aqueous solution amount and / or water amount calculated by the above from the alkali storage tank and / or the water charging means to the blending tank. An alkaline aqueous solution automatic blending device for weight reduction processing of polyester cloth, characterized by being provided. 4. The concentration detecting means comprises a density meter for measuring the density of the alkaline aqueous solution and an arithmetic means for calculating the concentration of the alkaline aqueous solution from the density measured by the density meter. Alkaline aqueous solution automatic blending device for weight reduction processing of polyester cloth.