JPH04343761A - Removal of water repellency function of fabric - Google Patents

Abstract

PURPOSE:To enable removal of water repellency function by applying low- temperature plasma treatment to a fabric subjected to water repellent finishing using a fluorine-based resin for the purpose of smooth reprocessing. CONSTITUTION:Low-temperature plasma treatment is applied to a textile fabric composed of a natural fiber, a synthetic fiber, etc., and subjected to water repellent finishing by using a fluorine-based resin to remove the water repellency function without change in color or touch. A fabric capable of smooth reprocessing (redyeing, refinishing, etc.) can be obtained thereby.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method for removing water repellency from a water-repellent fiber fabric by processing a fluorine-based resin.

0002

[Prior technology] After water-repellent treatment of textile fabric with fluorine-based resin, defects caused during the dyeing and finishing processes, such as uneven dyeing, dye skipping, medium dilution/medium density, poor pattern matching, doctor stains, resin stains, etc., were discovered. When this occurs, the resin is removed and water repellency is eliminated before reprocessing. If the resin can be easily removed, there will be no problem, but if the resin is highly durable, various problems will occur.

[0003] In recent years, there has been a strong demand for water repellent finishes with excellent durability, and fluorine-based resins are a representative example of durable water repellent finishing agents. Generally, the proposed method for removing the water repellency from water-repellent fabrics using fluorine-based resins is to remove the resin itself by treating it in a caustic soda bath at high temperature for a long time. Wool, silk, polyester, rayon, etc. are processed at high temperatures and for long periods of time.
If applied to fibers that are sensitive to alkali, it may damage the fibers or
It is not practical because it causes disadvantages such as yellowing and changes in texture.

0004

[Problems to be Solved by the Invention] The present invention has been made in view of the current situation, and is aimed at preventing changes in the hue and texture of water-repellent fiber fabrics that have been treated with a fluorine-based resin. The object of the present invention is to obtain a processing method that can remove the water repellency without causing it.

[0005]

[Means for Solving the Problems] The present invention achieves the above object and has the following configuration.

That is, the gist of the present invention is a method for removing water repellency from a fabric, which is characterized by subjecting a water-repellent fiber fabric processed with a fluorine-based resin to low-temperature plasma treatment.

The present invention will be explained in detail below. In the present invention, a fiber fabric treated with water repellency using a fluorine-based resin is used as an object of processing.

[0008] The fiber fabrics mentioned here include natural fibers such as cotton, wool, silk, and linen, semi-synthetic fibers such as viscose rayon and acetate fibers, nylon fibers, polyester fibers,
It refers to woven fabrics, knitted fabrics, nonwoven fabrics made of single fibers such as synthetic fibers such as polyacrylonitrile fibers and vinylon fibers, or woven fabrics, knitted fabrics, etc. made of blended yarns or blended yarns using two or more of these fibers in combination.

[0009] The fluorine-based resin referred to in the present invention has a fluoroalkyl group having 3 to 20 carbon atoms, preferably 6 to 12 carbon atoms, is insoluble in water, and has a melting point, glass transition point, or softening point of 20°C. or more, the molecular weight is about 700 to 200,0
00 compound. This fluorine-based resin is usually applied by a conventional method in the final step of processing the fiber fabric.

[0010] In the present invention, the above-mentioned fabric treated with a fluorine resin is subjected to low-temperature plasma treatment. In order to perform the low-temperature plasma treatment, a known device such as "Journal of Textile Machinery Society" Vol. 38, No. No. 18 of 4 (1985)
The following equipment described on page 8 can be used. This device has a structure in which a pair of discharge electrodes are installed in a vacuum container that can maintain a low pressure, a specific gas can be introduced at a predetermined flow rate, and the inside of the container can be evacuated using an attached vacuum pump to maintain a constant pressure. It is a device that has the following performance. When a voltage is applied to the electrodes in this device, a glow discharge occurs, and the introduced gas becomes a low-temperature plasma. most commonly 13.5
Apply high frequency power of 6 MHz. Low-temperature plasma treatment can be performed by passing the fabric to be treated at a desired speed through a low-temperature plasma atmosphere formed between electrodes.

Specifically, first, the fabric to be treated is placed in a vacuum container, and the pressure is evacuated using a vacuum pump to adjust the internal pressure to 0.01 to 10 Torr. Next, a predetermined gas is introduced and adjusted to 0.1 to 5 Torr. As the gas used at this time, various gases such as oxygen, nitrogen, argon, helium, ammonia, and air can be used. Oxygen, air, or argon are usually preferred. When a predetermined gas is introduced and high-frequency power is applied to the electrodes in the container while the pressure is adjusted to 0.1 to 5 Torr, the introduced gas becomes a low-temperature plasma state. High frequency power is 0.1~5W/c
m2 (electrode unit area) is appropriate. Low-temperature plasma treatment can be performed by passing a fabric previously housed in this low-temperature plasma atmosphere. The processing time is usually several seconds to 300 seconds, preferably 30 to 180 seconds.
Seconds. By performing the above-mentioned low-temperature plasma treatment,
A fiber fabric from which water repellency has been removed, which is the object of the present invention, can be obtained. The present invention has the above configuration.

0012

[Operation] In the present invention, the reason why the water repellency of the fluorine-based resin is removed by the low-temperature plasma treatment is not necessarily clear, but the inventor of the present invention conjectures as follows. The energy of electrons, ions, etc. in low-temperature plasma is extremely high, and as a result of this high-energy low-temperature plasma treatment, the molecular chains of the fluorine-based resin are severed.
It is presumed that water repellency will be lost.

[0013]

[Examples] Next, the present invention will be explained in more detail through Examples. The performance of the fabrics in the Examples was measured and evaluated by the following method. (1) Water repellency Determined according to JIS L-1092. (2) Evaluation was made by visual judgment using a fabric that had not been subjected to hue change treatment as a reference. (3) Texture change was evaluated by a handling test using the untreated fabric as a reference.

Example 1 A dyed twill fabric made of 100% polyester was prepared, and it was impregnated with a treatment solution consisting of 30 g/liter of Asahi Guard AG-310 (manufactured by Meisei Kagaku Kogyo Co., Ltd., fluororesin finishing agent). After squeezing the liquid with a mangle at a squeezing rate of 70%, 1
It was dried at 00°C for 3 minutes and cured at 150°C for 3 minutes.

The resulting water-repellent polyester twill fabric was used as a fabric to be processed, and it was divided into three parts, one of which was subjected to low-temperature plasma treatment under the following treatment conditions 1 to remove the water repellency of the fabric. . <Processing conditions 1> Gas type: 100% oxygen gas flow rate
: 5 liters/min vacuum degree: 1T
orr High frequency output: 0.5W/cm2 (unit electrode area) Processing time: 60 seconds

For comparison with the present invention, one of the twill fabrics divided into three parts was immersed in a solution of 3 g/liter of caustic soda (solid) according to a conventionally commonly used method.
℃ for 60 minutes. After treatment, it was washed with hot water, water, and dried. In addition, the remaining twill fabric divided into three was used for comparison as an untreated fabric in the present invention.

The performance of the fabrics of the present invention and comparative fabrics was evaluated, and the results are shown in Table 1.

[Table 1]

As is clear from Table 1, the conventional method causes changes in hue and texture, whereas the method of the present invention, which uses low-temperature plasma treatment, improves water repellency without causing any change in hue or texture. had been removed.

[0019]

Effects of the Invention The present invention has a structure in which a water-repellent fiber fabric made of a fluorine-based resin is treated with low-temperature plasma, and according to the method of the present invention having such a structure, the fluorine-based Water repellency can be removed from water repellent fiber fabrics by resin.

Claims (1)

[Claims] 1. A method for removing water repellency from a fabric, which comprises subjecting a water-repellent fiber fabric processed with a fluorine-based resin to low-temperature plasma treatment.