JPH06264363A - Batch-type knitted fabric product weight reduction method and apparatus - Google Patents

Abstract

(57) [Summary] [Object] To provide a product with a good texture by controlling the weight reduction processing more precisely in the weight reduction processing method of a knitted fabric product containing polyester fibers. [Structure] The caustic soda concentration in the processing tank containing the product is set to a certain optimum concentration, and the concentration during the hydrolysis reaction is always kept constant. Therefore, the concentration is continuously measured and kept within the deviation tolerance range. To continuously supply caustic soda. When this supply amount coincides with the required amount of caustic soda calculated from the amount of dough and the target reduction rate, the supply of caustic soda is stopped and the processing is terminated. [Effect] It is possible to reduce the amount of the desired texture in a short time by the treatment with the optimum concentration and is suitable for reuse of the treatment liquid.

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 reducing the weight of a batch type knitted fabric product.

[0002]

BACKGROUND OF THE INVENTION Methods for treating polyester knitted textile products with basic substances have been known for a long time. For example, it is disclosed in Japanese Patent Publication No. 37-3946.
Heat treatment of polyester fiber in caustic soda aqueous solution causes hydrolysis reaction, the outer layer of fiber is dissolved, the fiber itself becomes thin and can give a silky luster, so it has been widely applied as alkali weight reduction processing. It was In this alkaline weight reduction process, various studies have been conducted on how to control the weight loss rate to be obtained, and (a) the concentration of caustic soda in the treatment bath, (b) the type and concentration of the auxiliary agent in the treatment bath, ( C) Treatment temperature, (d) Treatment time,
(C) There are various documents regarding changes due to the bath ratio and the like.

For example, there is Dyeing Industry Vol.25 No.7 “About Weight Reduction Processing of Polyester Fiber” by Hiroshi Tanaka Dyeing Industry Vol.29 No.12 “About Acrylic Weight Reduction Processing of Polyester Fiber” by Motoharu Hasegawa. Moreover, the decrease in the concentration of the basic substance or the increase in the concentration of the hydrolysis product in the treatment bath is measured with time, and the end point of the weight reduction processing is determined based on the measured value.
There is a 4461 publication.

[0004]

Among the above-mentioned known documents,
Japanese Examined Patent Publication No. 37-3946 discloses that the properties of fibers are improved by using an amine as an auxiliary agent.
In the documents of Vol.25 and Vol.26, although the research results on the advantages and disadvantages of each control method for weight reduction processing are recognized, no on-site control means for practical use is disclosed.

Further, in Japanese Patent Publication No. 4-24461 mentioned above, a decrease in the concentration of a basic substance or an increase in the concentration of a hydrolysis product in a treatment bath is measured with time, and a change in the concentration is used as an index for "reduction of weight". The end point of processing "has been determined. However, in the present invention, since the concentration in the treatment bath changes, the texture due to weight reduction processing changes with the concentration change, so that the desired texture cannot be processed, and the reduction processing efficiency decreases as the concentration decreases. There is a defect that processing time is required and processing spots are generated due to a change in concentration.
Further, the influence of the temperature change of the treatment bath, especially the weight reduction processing under high temperature and high pressure is not disclosed, and there is a difference between the theoretical end point of the weight reduction processing reaction and the end of the actual weight reduction processing operation. Although it is recognized, since no correction means is used, there is a problem that the error is large in setting the target weight reduction rate.

The object of the present invention is to eliminate the above-mentioned drawbacks and to precisely control the amount of caustic soda to be subjected to weight reduction processing in accordance with the target weight reduction rate while maintaining the concentration of caustic soda at a constant optimum concentration. Regarding the treatment under high temperature and high pressure, especially by adding the correction based on the empirical value in the cooling process,
Provide a weight reduction processing method and apparatus capable of realizing more accurate weight reduction processing, processing to a desired texture, greatly shortening processing time, preventing processing unevenness, and facilitating reuse of processing liquid. It is what

[0007]

To achieve the above object, in the first invention, a knitted fabric product is put into a treatment tank in a weight reduction processing method in which a knitted fabric product containing polyester fibers is dissolved in caustic soda or other alkaline aqueous solution. Then, the concentration of caustic soda in the treatment liquid is set to a certain optimum concentration, during the hydrolysis reaction, caustic soda is replenished to maintain the optimum concentration, and the amount of the replenished caustic soda is continuously integrated to obtain the fiber. Weight reduction method for batch type knitted woven products in which the required amount of caustic soda is calculated in advance from the input amount of the product and the target weight reduction rate, and the supply of caustic soda is stopped at the time when the integrated amount and the required amount match and the processing is terminated. And

In the second invention, when the knitted fabric product is treated under high temperature and high pressure, from the required amount of caustic soda calculated by the input amount of the knitted fabric product and the target weight reduction rate, the amount of caustic soda consumed during the cooling step ( The required amount of correction was calculated by subtracting (empirical value), and the time when the required amount of correction and the integrated amount of the replenished caustic soda coincided with each other was used as the starting point of the cooling process, and the weight reduction processing method of the batch type knitted and woven fabric product was performed.

In the third invention, as an empirical value, the amount of caustic soda to be replenished for maintaining the concentration even after the start of the cooling step is an empirical value.
(1), stop the replenishment, and use the experiential value (2) as the amount consumed until the end of the hydrolysis reaction after the end of processing, and start the cooling process from the experiential values (1) and (2). This was a method for reducing the weight of batch-type knitted and woven products at fixed time points. According to a fourth aspect of the present invention, in a weight reduction processing method in which a knitted fabric product containing polyester fibers is dissolved in caustic soda or another alkaline aqueous solution, the knitted fabric product is put into a treatment tank to adjust the concentration of caustic soda in the treatment liquid to a certain optimum concentration. Set, during the hydrolysis reaction, the caustic soda is replenished to maintain the optimum concentration, and the amount of the replenished caustic soda is continuously integrated, and the required amount of caustic soda is obtained in advance from the input amount of the fiber product and the target weight reduction rate. Calculate the amount of caustic soda consumed until the end of the reaction by stopping the supply of caustic soda as the empirical value, subtract this empirical value from the required amount to calculate the correction required amount, and The batch-type knitted and woven fabric product weight reduction processing method in which the supply is stopped and the processing is terminated when the integrated amount of the supplied caustic soda matches.

As an apparatus for carrying out these methods, in the fifth invention, a knitted fabric product is put into a treatment tank in a weight reduction processing device for dissolving a knitted fabric product containing polyester fibers in an alkaline aqueous solution such as caustic soda. Then, setting means for setting the concentration of caustic soda in the treatment liquid to a constant optimum concentration, measuring means for continuously measuring the concentration of caustic soda in the hydrolysis reaction, and the measured value by the measuring means and the set concentration Replenishment adjusting means for replenishing so as to keep the concentration of caustic soda constant within the allowable deviation range based on the deviation value,
Calculation means for integrating the amount of the replenished caustic soda,
Calculation means for calculating in advance the required amount of caustic soda from the weight of the knitted and woven products that have been input and the target weight reduction rate, and a means for comparing the cumulative amount of caustic soda replenished by the replenishment adjustment means and the required amount by the calculation means. The batch-type knitted and woven fabric product weight-reduction processing apparatus comprises means for stopping the replenishment of caustic soda and ending the weight-reduction processing step when the required amount and the integrated amount match with each other by the comparison means.

In a sixth aspect of the present invention, in a high-temperature and high-pressure weight loss processing apparatus, an input means for setting the amount of caustic soda consumed during the cooling step as an empirical value, the weight of the knitted and woven product put in, and a target weight reduction rate are used in advance. Calculating means for calculating the required amount, a calculating means for obtaining the corrected required amount by subtracting the amount based on the empirical value from the required amount, and a means for comparing the corrected required amount and the integrated amount of the replenished caustic soda. ,
The batch type knitted and woven product weight reduction processing apparatus comprises a cooling step start means that operates when the required correction amount and the integrated amount match with each other by the comparison means.

[0012]

In the first aspect of the present invention, by setting the concentration of caustic soda to a certain optimum concentration, the hydrolysis reaction can be progressed so as to obtain a desired texture according to the type of polyester fiber and the structure of knitted fabric. It became so. In order to maintain the optimum concentration, the concentration was continuously measured so as not to fluctuate, and the caustic soda was replenished and adjusted.

The cumulative amount of caustic soda by adjusting the supply of caustic soda is the cumulative amount of caustic soda that has been subjected to weight reduction processing up to that point, and the required amount of caustic soda calculated in advance from the weight of the knitted fabric product to be input and the target weight reduction rate ( The theoretical amount of reduction) was compared with the integrated amount, and when they coincided, the supply of caustic soda was stopped and the processing was terminated. According to the second aspect of the invention, in the weight reduction process under high temperature and high pressure, the starting point of the cooling process is particularly important during each process of raising the temperature, maintaining the temperature constant, and cooling, and the determination of this starting point is consumed in advance during the cooling process. The amount of caustic soda produced is set as an empirical value.

The weight reduction process is controlled with the time when the corrected required amount obtained by subtracting the above-mentioned empirical value from the theoretical required amount of caustic soda matches the integrated amount of the replenished caustic soda as the starting point of the cooling process. . In the third invention,
As an empirical value, the amount of caustic soda that is replenished to maintain the concentration after the start of the cooling process is set as the empirical value (1). The amount consumed further is set to the experience value (2), the supply of caustic soda is stopped based on the experience values (1) and (2), the end point of the processing is determined, and the weight reduction processing is controlled until the end. This has improved the precision.

In the fourth aspect of the invention, as the weight reduction processing under normal pressure, there is a phenomenon that the hydrolysis reaction as the weight reduction processing is extremely lowered at a temperature of about 85 ° C. or less,
When the reduction processing is performed at 90 ° C. or higher, the supply of the caustic soda is stopped, and even after the processing is finished, a slight reaction proceeds until the discharge of the treatment liquid and the washing step, and the caustic soda is consumed. This consumption amount is set as an experience value.

When the corrected required amount obtained by subtracting the above empirical value from the required amount of caustic soda based on the theoretical weight reduction rate matches the integrated amount of the replenished caustic soda, the stop of the replenishment and the end point of the processing are set. In the fifth invention, as a device for carrying out the above-mentioned weight reduction processing, a setting means for setting the concentration of caustic soda to a constant optimum concentration is provided, and a measuring means for continuously measuring the concentration of caustic soda in the hydrolysis reaction is provided. The replenishment adjusting means replenishes the caustic soda so that the concentration of the caustic soda is always kept constant on the basis of the deviation value between the value measured by the measuring means and the concentration set by the setting means. The replenishment amount is controlled within the deviation allowable value range.

The required amount of caustic soda according to the theoretical weight loss rate,
The comparison means compares the accumulated amount of the caustic soda replenished by the replenishment adjusting means, issues a command when the two coincide with each other, stops the replenishment of the caustic soda, and ends the weight reduction processing. In the sixth aspect of the present invention, in the high-temperature and high-pressure weight reduction processing apparatus, since the weight reduction processing rate in the state where the temperature is kept constant and the weight reduction processing rate in the state in which the cooling step is started are different, they are consumed during the cooling step. An input means is provided to input the amount of caustic soda as an empirical value.

The correction required amount obtained by subtracting the amount based on the above-mentioned empirical value from the required amount of caustic soda based on the theoretical weight reduction rate is compared with the cumulative amount of caustic soda replenished during the weight reduction processing, and when the both coincide with each other. Then, the cooling process was started.

[0019]

EXAMPLES The present invention will be described below based on examples. (1) Preparation process Polyester fiber knitted fabric (hereinafter referred to as fabric) in the processing tank
Then, put on the control panel for weight reduction <provisional> treatment liquid volume (l), dough volume (Kg), target weight reduction rate (%), <provisional> initial bath concentration (g /
l) and experience value (%) are entered as conditions.

<Tentative> The initial bath concentration is set to an optimum concentration according to the type and structure of polyester fiber and the desired texture, and the deviation tolerance is determined. (Starting supply) Water and caustic soda or the recovery liquid are supplied to the processing tank based on the input amount of the processing liquid and the <tentative> initial bath concentration.

(Measurement of Concentration) Since the water contained in the dough and the water remaining in the treatment tank are added and diluted in the treatment tank, after stirring the whole, the concentration is measured again, Determine the constant holding concentration. (2) Start of processing The weight reduction processing device is operated based on the program pattern to start processing.

(Concentration measurement) When the treatment is started, a part of the treatment liquid is circulated from the treatment tank to the concentration measurement sensor and back to the treatment tank, and the sensor continuously measures the concentration in real time. (Replenishment adjustment) The measured value from the densitometer is compared with the above-mentioned constant holding concentration, and the caustic soda is constantly replenished and adjusted so as to maintain the allowable deviation value.

(Integration of replenishing caustic soda) The amount of replenished caustic soda is integrated by using an integrating electromagnetic flow meter. (Comparison of cumulative amount and required amount of caustic soda) The required amount calculated from the amount of dough input and the target weight reduction rate is calculated in advance. Required amount = Dough input amount x Target weight loss rate x (80/192) This is easily calculated because 2 mol of NaOH is required for hydrolysis with 1 mol of polyethylene terephthalate (PET).

The required amount and the integrated amount are compared with each other, and the point of time when the two coincide with each other is set as the end point of the weight reduction processing. (3) Correction based on empirical value (in case of high temperature and high pressure equipment) Cooling process based on empirical value from the necessary amount which was calculated in advance from the dough weight and the target weight reduction rate for which the cumulative amount of replenished caustic soda was first condition input The time point corresponding to the amount obtained by subtracting the amount consumed is used as the starting point of the cooling process.

(Experimental value) (a) A pair value of a weight reduction rate predicted to proceed during cooling and a time (cushion time) from when a cooling start signal is output to when cooling is actually started is preset. deep. The empirical value was subtracted from the necessary amount based on the theoretical weight reduction rate to calculate a correction required amount, and the time when the correction required amount coincided with the integrated amount of the replenished caustic soda was set as the cooling start point.

(B) Replenishment of caustic soda is continued even after the start of cooling, and integration is also continued. At this time, there is a difference in the weight reduction rate during the cooling process compared to the case where the temperature is kept constant, and this is input in advance as the empirical value (1). Next, the amount of caustic soda that is drained or collected from the time when the supply of caustic soda is stopped and then the washing water is supplied until the hydrolysis reaction is completely completed is entered in advance as the empirical value (2). I'll do it. The cooling start time was set based on these empirical values (1) and (2).

(In the case of a normal pressure device) The amount of caustic soda consumed from the time when the supply of caustic soda is stopped until the state in which the hydrolysis reaction does not substantially progress is preset as an empirical value. The correction required amount is calculated by subtracting this empirical value from the required amount based on the theoretical weight reduction rate.

When the required correction amount coincides with the integrated amount of the replenished caustic soda, the replenishment is stopped and the processing is controlled as the end point. (4) Termination of weight reduction processing (drainage / recovery) When the cooling process is completed in the high temperature and high pressure equipment or the hydrolysis reaction is completed in the atmospheric pressure equipment, the treatment liquid in the treatment tank is discharged.

Since the treatment liquid has maintained a constant set concentration, it is collected in the collection tank so that it can be reused for the next processing. (Wash) Wash the dough so that it can be taken out. (Fabric take-out) The dough is taken out using a dough-drawing device.

Hereinafter, a weight reduction processing apparatus for carrying out the method of the present invention will be described. Reference numeral 1 is a processing tank, and 2 is a transfer pipe, which are connected to each other at both ends to form an annular processing device. Reference numeral 3 is a processing liquid circulation path, which is provided with a pump 4 and a heat exchanger 5 and draws the processing liquid from several points in the processing tank 1 to form a pump 4 and a heat exchanger 5.
It is a path that returns to the processing tank 1 via.

Reference numeral 6 is a caustic soda concentration measuring device as a measuring means, and the conductivity in the treatment liquid is directly measured by an electric conductivity meter. An annular path from the treatment tank 1 to the concentration measuring device 6 via the cooler 7 and back to the transfer pipe 2 is taken, and the concentration of caustic soda in the treatment tank is continuously measured. 8 is a caustic soda stock tank, 9 is a pump, 10
Is an integrating electromagnetic flowmeter, and 8 to 10 are replenishment adjusting means. Reference numeral 11 denotes a central processing unit (CPU), which is a calculation means for calculating the required amount of caustic soda, a means for comparing the required correction amount obtained by subtracting the consumption amount based on experience values from the required amount and the accumulated amount, and a stop for stopping the supply of the caustic soda. The means etc. are calculated and a command is issued. Reference numeral 12 is a recovery tank, which is designed to recover the processing liquid after the end of the weight reduction processing. The pump 9 may be a metering pump and the flow meter 10 may be omitted.

The knitted and woven fabric product is put into the treatment tank 1, the concentration of caustic soda in the treatment liquid is set to a constant optimum concentration, the concentration is constantly measured by the concentration measuring device 6, and the concentration is kept constant within the allowable deviation range. In order to maintain it, CPU 11 orders the caustic soda stock tank 8 to pump 9, integrating electromagnetic flow meter.
It is controlled to constantly supply caustic soda through 10.
The cumulative amount of the caustic soda supplied is linked to the hydrolysis reaction in the processing tank 1 and is always supplied in the same amount as the amount of the caustic soda consumed. Since the concentration is controlled so as not to fall out of the deviation tolerance range, the integrated amount replenished matches the amount of caustic soda used for the hydrolysis reaction of the polyester fiber.

[0033]

According to the method of the present invention, since the concentration of the treatment liquid can be set to a constant optimum concentration, it is possible to appropriately set the concentration of caustic soda suitable for the type and structure of the knitted fabric product and the texture required. Even when finishing with the same silk touch, it is possible to control the roughness and glossiness of the texture, and the processing time is 1/2 to 1 by increasing the density.
It has been shortened to / 3, or the concentration has been set to a relatively low value to finish the texture with flexibility over time.

Moreover, since the concentration is always constant, the weight reduction processing rate hardly changes, and the weight reduction processing can be advanced under a constant condition, so that problems such as weight loss unevenness can be eliminated. When the high temperature and high pressure device is used as in the second aspect of the invention, the weight reduction rate is different during the steps of raising the temperature, maintaining the constant temperature, cooling, etc., especially when the cooling step is started, so that it is consumed after the start of the cooling step. By inputting the amount of caustic soda as an empirical value in advance, a corrected required amount obtained by subtracting the empirical value from the required amount of caustic soda calculated from the theoretical weight loss rate can be obtained, and a more accurate weight loss rate can be achieved. Became. In addition, the cooling start point can be set and executed by continuously and accurately observing the progress of the hydrolysis reaction by comparing the above-mentioned correction required amount and the replenished integrated amount.

In the third aspect of the invention, when the experience value is further input, the change in the weight reduction rate in the state where the supply of caustic soda is continued is defined as the experience value (1), and after the supply is stopped, the hydrolysis reaction is terminated. By inputting the amount of as the empirical value (2), it becomes possible to control until the end of the weight reduction processing, and it becomes possible to perform processing with a more precise target weight reduction rate.

In the case of the atmospheric device of the fourth aspect of the present invention, the amount of caustic soda consumed until the end of the reaction after the supply of caustic soda is stopped is input as an empirical value, and a precise weight reduction processing can be realized. It became so. The fifth invention and the sixth invention are apparatuses for carrying out the above-mentioned weight reduction processing, and from the setting of the optimum concentration at the beginning of the head, the concentration can be continuously measured when maintaining this concentration, for example, using an electric conductivity meter. As a result, by constantly supplying caustic soda within the allowable deviation range, the setting conditions for weight reduction processing can be kept in an optimum state. Therefore, it is possible to carry out the desired weight reduction processing with a good texture in a short time, and since the concentration of the treatment liquid after the treatment has always been kept constant, there is no need to re-adjust to the initial concentration upon reuse, and it is easy to use. It has become a thing.

Although the present invention describes a knitted or woven product containing polyester fibers, it can also be applied to the case of reducing the amount of fibers such as acetate dissolved in an alkaline aqueous solution.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a device of the present invention.

[Explanation of symbols]

 1 processing tank 6 measuring means 8-10 replenishment adjusting means 11 calculating means

Claims (6)

[Claims] 1. In a weight reduction processing method of dissolving a knitted fabric product containing polyester fibers in caustic soda or another alkaline aqueous solution, the knitted fabric product is put into a treatment tank to bring the concentration of caustic soda in the treatment liquid to a certain optimum concentration. Set, during the hydrolysis reaction, the caustic soda is replenished to maintain the optimum concentration, and the amount of the replenished caustic soda is continuously integrated, and the required amount of caustic soda is obtained in advance from the input amount of the fiber product and the target weight reduction rate. A method for reducing the weight of a batch-type knitted or woven product, which comprises calculating, and stopping the supply of caustic soda at the time when the integrated amount and the required amount match, and ending the processing. 2. The amount of caustic soda consumed during the cooling process (empirical value) from the required amount of caustic soda calculated from the input amount of the knitted textile product and the target weight reduction rate when treating the knitted textile product under high temperature and high pressure. Calculate the required correction amount by subtracting
The method for reducing the weight of a batch-type knitted or woven product according to claim 1, wherein a time point when the required correction amount and the integrated amount of the replenished caustic soda are coincident with each other is used as a starting point of the cooling step. 3. As an empirical value, the amount of caustic soda to be replenished to maintain the concentration after the start of the cooling step is set as an empirical value (1), the replenishment is stopped, and consumption is performed after the processing is completed and until the hydrolysis reaction is stopped. The amount to be used is the experience value (2), and the experience value (1)
3. The method for reducing the weight of a batch type knitted fabric product according to claim 2, wherein the starting point of the cooling step is determined from (2). 4. A weight reduction processing method in which a knitted fabric product containing polyester fibers is dissolved in caustic soda or another alkaline aqueous solution, wherein the knitted fabric product is put into a treatment tank so that the concentration of caustic soda in the treatment liquid is a constant optimum concentration. Set, during the hydrolysis reaction, the caustic soda is replenished to maintain the optimum concentration, and the amount of the replenished caustic soda is continuously integrated, and the required amount of caustic soda is obtained in advance from the input amount of the fiber product and the target weight reduction rate. Calculate the amount of caustic soda consumed until the end of the reaction by stopping the supply of caustic soda as the empirical value, subtract this empirical value from the required amount to calculate the correction required amount, and A method for reducing the weight of batch-type knitted and woven products, characterized in that the supply is stopped and the processing is terminated when the cumulative amount of the supplied caustic soda matches. 5. In a weight reduction processing apparatus for dissolving a knitted fabric product containing polyester fibers in an alkaline aqueous solution such as caustic soda, the knitted fabric product is put into a treatment tank so that the concentration of the caustic soda in the treatment liquid becomes a constant optimum concentration. And the setting means
Measuring means for continuously measuring the concentration of caustic soda in the hydrolysis reaction, and to keep the concentration of caustic soda constant within the deviation allowable value based on the deviation between the measured value by the measuring means and the set concentration. Replenishment adjusting means for replenishing, calculating means for accumulating the amount of the replenished caustic soda, calculating means for preliminarily calculating the necessary amount of caustic soda from the weight of the introduced knitted fabric product and the target weight loss rate, and the replenishment adjustment Means for comparing the cumulative amount of caustic soda replenished by the means with the required amount by the calculating means, and when the required amount and the cumulative amount match by the comparing means, the replenishment of the caustic soda is stopped, and the weight reduction process is completed. A batch-type knitting / fabric product weight-reduction processing device comprising: 6. A required amount of caustic soda in advance in a high-temperature and high-pressure weight loss processing apparatus, based on an input means that uses the amount of caustic soda consumed during a cooling step as an empirical value, and the weight of a knitted and woven product that has been introduced and the target weight reduction rate. A calculation means for calculating
Calculation means for obtaining a correction required amount by subtracting the amount based on the empirical value from the required amount, comparing means for the corrected required amount and the integrated amount of the replenished caustic soda, and the corrected required amount by the comparing means. 6. The batch type knitted and woven product weight reduction processing apparatus according to claim 5, further comprising a cooling step starting means that operates at a time point when the integrated amount matches.