JP2942917B2 - Method for producing a polyester fiber fabric processed by etching - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a discharge-treated polyester fiber fabric.

[0002]

2. Description of the Related Art Conventionally, one of the constituent fibers is partially removed from a fabric obtained by blending, blending, or knitting and mixing two or more kinds of different fiber materials such as polyester fiber and cotton, rayon, silk, and acetate fibers. The method of forming a watermark pattern by using a known method is known as opal processing, but in a known method, the same color property between different kinds of fibers cannot be obtained, the dye is discolored by a discharge agent, and the printed pattern is discharged. There are problems such as not matching the pattern and high cost.

[0003] Further, in the removal processing of polyester-based fibers, an amine, an alkali metal hydroxide, an inorganic acid, an organic acid, or the like is printed and adhered to a cloth made of modified polyester fibers and unmodified polyester fibers as a removal agent. There is also known a method of forming a watermark pattern by heat treatment followed by embrittlement of the modified polyester fiber and erosion.

[0004] However, the method using an amine has an environmental problem due to the generation of offensive odor, smoke and the like during the heat treatment. Further, the method using an alkali metal hydroxide has a risk of embrittlement even of the unmodified polyester fiber which should be originally left, and has a problem such as a decrease in the strength of the fabric. Further, the method using an inorganic acid, an organic acid, or the like has problems such as generation of offensive odor, generation of smoke, etc. during heat treatment, monotonous watermark pattern, and lack of sharpness at the time of molding. In addition, a dye is contained in the printing paste, and when dyeing the polyester fiber of the printing portion, a conventional amine, an alkali metal hydroxide, an inorganic acid, an organic acid and the like are used in the printing paste using a disinfectant. Then, there is a problem that the dye is discolored and a satisfactory hue cannot be obtained.

[0005]

SUMMARY OF THE INVENTION The present invention provides a method for printing by using an accelerator which causes a modified polyester fiber in a fabric composed of a modified polyester fiber and an unmodified polyester fiber to become brittle preferentially when the alkali weight is reduced. The purpose of the present invention is to positively decompose the modified polyester and suppress the decomposition of the unmodified polyester.The object of the present invention is to have a very sharp watermark pattern on the mold side, and there is no discoloration of the dye in the printing paste, It is an object of the present invention to provide an exfoliated polyester fiber fabric in which a pattern portion having a clear hue is formed and which is excellent in design.

[0006]

[0007]

SUMMARY OF THE INVENTION The present invention resides in a method for producing an exfoliated polyester fiber fabric comprising the following steps. (B) a step of coloring at least a part of a fabric comprising a modified polyester fiber and an unmodified polyester fiber containing a third component as a copolymerization component and ethylene terephthalate as a main repeating unit with a ground dye, (b) polyhydric alcohol ethylene oxide At least a portion of a discoloration paste containing an adduct and a dye decomposer and / or a polyhydric alcohol ethylene oxide adduct, a disintegration agent and a discoloration paste containing a non-decomposable dye in the dye decomposer and alkali (C) Heat treatment at a temperature of 100 to 240 ° C. (d) Alkali treatment to remove the modified polyester fiber in the printed area and to remove the colored unmodified polyester fiber in the printed area The process of removing the ground dye

[0008] The discharge-treated polyester fiber cloth according to the present invention is a discharge-treated cloth comprising a modified polyester fiber containing a third component as a copolymerization component and ethylene terephthalate as a main repeating unit, and an unmodified polyester fiber, The exfoliated portion is made of unmodified polyester fiber that is uncolored or is simultaneously colored and exfoliated, in which the denatured polyester fiber has been removed, and the exfoliated portion is entirely or partially grounded. All or a part of the modified polyester fiber and the unmodified polyester fiber are ground-dyed and dyed.

In the present invention, the modified polyester fiber is a fiber comprising a polyester containing a third component as a copolymer component and having ethylene terephthalate as a main repeating unit, and an unmodified polyester fiber is a fiber containing a third component. Is a fiber composed of a polyester containing 0.5 mol% or less of ethylene terephthalate as a main repeating unit.

As the modified polyester fiber, as the third component, isophthalic acid, hexahydroterephthalic acid, adipic acid, sebacic acid, cyclohexanedicarboxylic acid,
Dicarboxylic acids such as azelaic acid; tricarboxylic acids such as trimellitic acid; 5-sodium sulfoisophthalic acid;
Diols such as methylsulfoisophthalic acid, polyalkylene glycol, diethylene glycol, tetramethylene glycol, hexamethylene glycol, hexanediol, bisphenol A and bisphenol B;
Fibers made of polyester modified by copolymerizing 1 to 15% by combining one or two or more of them are exemplified.

In the present invention, the modified polyester fiber is preferably polyethylene terephthalate obtained by copolymerizing an aliphatic dicarboxylic acid such as adipic acid and sebacic acid with 5-sodium sulfoisophthalic acid, and more preferably 3 to 7 mol of adipic acid. % Polyethylene terephthalate obtained by copolymerizing the sodium terephthalate with 1.5% to 4% by mole of 5-sodium sulfoisophthalic acid. Further, as the unmodified polyester fiber, a fiber made of polyethylene terephthalate is preferably used.

In the present invention, a fabric comprising a modified polyester fiber and an unmodified polyester fiber is a fabric in which a modified polyester fiber and an unmodified polyester fiber are combined in an arbitrary form, and is blended, blended, intertwisted, and intertwisted. It refers to knitted fabrics, woven fabrics, etc. by knitting, weaving and the like. The ratio between the modified polyester fibers and the unmodified polyester fibers in the fabric may be arbitrary.

In the present invention, the disintegrated polyester fiber fabric is manufactured by the steps (a), (b), (c) and (d). In the step (a), all or a part of the cloth is dyed with a ground dye or dyed by printing. Dyeing or printing is performed by any known method. Land dyes include known thiazole azo dyes,
Either a quinolone azo-based disperse dye or an imino-based disperse dye may be used, and a disperse dye which is not easily decomposed by an alkali is preferably used.

In the present invention, in the step (b), the colored fabric is printed with a discharge paste containing a polyhydric alcohol ethylene oxide adduct as a weight loss promoter and a dye decomposer for decomposing the ground dye. It is necessary. The polyhydric alcohol ethylene oxide adduct to be contained in the disinfecting paste is a product obtained by adding 2 mol or more of ethylene oxide to the polyhydric alcohol, and the polyhydric alcohol includes ethylene glycol, propylene glycol, hydrobenzoin,
Dihydric alcohols such as benzopinacol, cyclopentane-1,2-diol and cyclohexane-1,4-diol, and trihydric alcohols such as glycerin are used.

The method of adding ethylene oxide to the polyhydric alcohol is not particularly limited, and a generally known method is used to produce an adduct. In the present invention, the polyhydric alcohol ethylene oxide adduct preferably used includes ethylene glycol 5 to 3 of ethylene glycol.
0 mole adduct, ethylene oxide of glycerin 3-28
And molar adducts. The polyhydric alcohol ethylene oxide adduct varies depending on the type of the modified polyester fiber, the ratio in the fabric, and the like.
g, preferably 5 to 20 g.

As the dye decomposer to be contained in the exfoliating paste,
A reducing agent is used, preferably stannous chloride, stannous phosphate, stannous benzoate, stannous trimellitate, stannous such as stannous silicate, zinc formaldehyde sulfoxylate, etc. And the like.

Known sizing agents are used as the sizing agent for the disinfecting paste, and include natural, processed, semi-synthetic, and synthetic materials such as wheat starch, tragacanth gum, locust bean gum, carboxymethyl cellulose, polyvinyl alcohol, and sodium polyacrylate. The sizing agent may be used alone or in combination of two or more. Among the acid-resistant sizing agents, natural gums such as crystal gum, locust bean gum, guar gum, highly etherified starch, highly etherified cellulose derivative paste, O / W-type emulsions and the like are preferred.

Further, in the present invention, a dye may be contained in the discharge paste, and a discharge paste containing a polyhydric alcohol ethylene oxide adduct, a dye decomposer and a dye is used as the discharge paste. In addition, dyeing can be performed simultaneously with the etching process. The use of a disperse dye as a dye to be contained is not discolored by a polyhydric alcohol ethylene oxide adduct, so that a clear hue can be obtained.
It is a good thing. As the disperse dye, any disperse dye can be used as long as it is a dye decomposer in the discoloring paste and a disperse dye that can withstand alkali treatment in a subsequent step, and particularly preferably a quinone-based disperse dye or a quinophthalone-based disperse dye is used. Can be

Printing of the discharge paste on the fabric is carried out by any known method. At least a part of the cloth is printed so as to overlap with the colored portion by the ground dye, and almost all of the printed pattern is printed. It is arbitrarily printed up to the printing of. In addition, a polyhydric alcohol ethylene oxide adduct, a disintegrating paste containing a dye-decomposing agent and a polyhydric alcohol ethylene oxide adduct, a disintegrating agent and a disintegrating agent and a non-decomposable dye-containing disinfecting color paste are used as alkalis. After printing a polyalcohol ethylene oxide adduct and a disinfectant paste containing a dye-decomposing agent, further apply a polyalcohol ethylene oxide adduct, a disintegrant and a disinfectant paste containing a dye to the colored portion and / or It may be printed by partially overlapping with the printing part of the discharge paste of the above, or after changing the order and printing the discharge color paste containing polyhydric alcohol ethylene oxide adduct, dye decomposer and dye,
A polyhydric alcohol ethylene oxide adduct and a disintegrating paste containing a dye decomposer may be printed.

After printing and drying, in the step (c), the fabric is heated to a temperature of 100 to 240 ° C., preferably 125 to 200 ° C.
Heat treatment. After printing and heat treatment, it is desirable to perform reduction washing with hydrosulfite or the like in order to obtain a clear color. This reduction cleaning may be performed simultaneously with the subsequent alkali treatment.

In the heat treatment after printing in the present invention,
The modified polyester fiber in the printing area has a looser amorphous structure than the amorphous polyester fiber in the unmodified polyester fiber.
The polyhydric alcohol ethylene oxide adduct easily penetrates into the amorphous structure of the modified polyester fiber, and the infiltrated polyhydric alcohol ethylene oxide adduct swells in a high-temperature atmosphere and is significantly decomposed during alkali treatment in a later step. It has a promoting effect. In this heat treatment, the colored portion of the printed portion with the ground dye is completely removed by the dye-decomposing agent, and if there is a dye-decomposing agent and a disperse dye that can withstand alkali treatment, coloring is performed.

In the alkali treatment of the step (d) after the heat treatment in the present invention, an alkali weight reduction treatment usually applied to polyester fibers is applied, and an alkali metal hydroxide such as sodium hydroxide and potassium hydroxide; The fabric is immersed as an aqueous alkali solution using an alkali such as an alkaline earth metal hydroxide such as calcium or magnesium hydroxide, and optionally using an amine such as triethanolamine, diethanolamine or monoethanolamine. The treatment conditions can be appropriately changed according to the fineness of the fibers constituting the fabric, the weight loss rate, and the like.
The concentration is appropriately selected within the range of g / l, and preferably 50 g / l or less in the case of a fine fiber fabric. The processing temperature is 60 to 120C, preferably 90 to 110C.

In the alkali treatment of the present invention, the modified polyester fiber is brought into a state in which embrittlement is liable to occur beforehand by adhesion of polyhydric alcohol ethylene oxide adduct and heat treatment, and the unmodified polyester fiber is converted into polyhydric alcohol ethylene oxide. Alkali treatment decomposes and removes only the denatured polyester fiber to which the polyhydric alcohol ethylene oxide adduct has adhered in the printed area, and the printed area is uncolored or colored. The unmodified polyester fiber forms a stripped portion that remains without being decomposed and removed, and the non-printed portion becomes a non-dipped portion composed of a modified polyester fiber and an unmodified polyester fiber at least partially colored, and a watermark pattern is formed. The formed exfoliated fabric is obtained.

The polyester fiber fabric which has been subjected to the etching process according to the present invention can of course be subjected to ordinary dyeing or printing after the etching process. A variety of advanced design effects can be imparted by the combination of the hue and the pattern in the processing.

[0025]

The present invention will be described below in more detail with reference to examples.

Example 1 5 mol% of adipic acid and 5-
Plain knitting of 24G using a yarn obtained by twisting a modified polyester fiber 75d / 48f made of 2.25 mol% of sodium sulfoisophthalic acid copolymerized polyethylene terephthalate and a polyethylene terephthalate fiber 75d / 36f at a twist number of 120 T / M. did. The following printing paste (1) was printed in a pattern on the knitted fabric and dried at 110 ° C. for 2 minutes. Thereafter, the following disinfecting paste (2a) is printed in a pattern so as to partially overlap the printing paste (1), and the temperature is 180 °.
Heat treatment was performed for 90 seconds in a saturated steam atmosphere at 90 ° C. The adhesion rate of the disinfecting paste (2a) to the knitted fabric was 120% by weight on average.

Printing paste (1): 2 parts by weight of Dyanix Red T2B-FS (disperse dye manufactured by Mitsubishi Kasei Hoechst) Fine gum G17 6 parts by weight (guar gum paste manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Water 92 parts by weight

Glue paste (2a): glycerin ethylene oxide 10 mol adduct 12 parts by weight Fine gum NT-7P (glue) 10 parts by weight Stannous chloride 9 parts by weight Dicyandiamide (acid absorbent) 2 parts by weight Water 67 parts by weight Department

Thereafter, the heat-treated knitted fabric is subjected to alkali treatment at a boiling temperature for 45 minutes in the following alkaline aqueous solution (3),
Neutralized and dried by a conventional method. The obtained knitted fabric is printed paste (1) in the printed area, and the discharge paste (2a), in the non-printed area, is clearly colored red, and in the discharge paste (2a) printed area, the modified polyester fiber is used. The unmodified polyethylene terephthalate fiber which had been completely decomposed and removed and was color-removed remained without damage, and a knitted fabric which had been etched to a very sharp openwork pattern at the time of molding was obtained. In addition, there was no generation of offensive odor or smoke during the heat treatment.

Alkaline aqueous solution (3): sodium hydroxide 15 g / l hydrosulfite 5 g / l sodium carbonate 10 g / l bath ratio 1:50

Example 2 The same knitted fabric as used in Example 1 was immersed in the printing paste (1) and squeezed with a mangle at 110 ° C.
For 2 minutes. Then, after the above-mentioned exfoliating paste (2a) was printed in a pattern, 90 ° C. in a saturated steam atmosphere at a temperature of 180 ° C.
Heat treated for seconds. The adhesion ratio of the printing paste (1) and the discharge paste (2a) to the knitted fabric was 200% by weight and the average was 120% by weight.

Thereafter, the heat-treated knitted fabric was subjected to alkali treatment in an aqueous alkaline solution (3) at a boiling temperature for 45 minutes, and neutralized and dried by a conventional method. The obtained knitted fabric is exfoliated paste (2a)
The non-printed part is colored vividly red, and the printed paste (2a) printed part has the denatured polyester fiber completely decomposed and removed.
The uncolored unmodified polyethylene terephthalate fiber remained without damage, and a knitted fabric was obtained which had been processed into a very sharp openwork pattern at the time of molding. In addition, there was no generation of offensive odor or smoke during the heat treatment.

(Example 3) Extrusion processing was performed in the same manner as in Example 1 except that the heat treatment was changed to a heat treatment for 90 seconds in a dry heat atmosphere at a temperature of 200 ° C. The obtained knitted fabric is printed paste (1) in the printed area, and the discharge paste (2a), in the non-printed area, is clearly colored red, and in the discharge paste (2a) printed area, the modified polyester fiber is used. The unmodified polyethylene terephthalate fiber, which has been completely decomposed and removed, and has been removed, remains without damage. The polyethylene terephthalate fiber in the overlapping portion of the printing paste (1) and the printing paste (2a) printing part is removed. A knitted fabric was obtained which had been colored and subjected to an etching process with an extremely sharp openwork pattern. In addition, there was no generation of offensive odor or smoke during the heat treatment.

(Comparative Example 1) An etching process was performed in the same manner as in Example 1 except that triethanolamine was used in place of the 10 mol glycerin ethylene oxide adduct of the exfoliating paste (2a). In this process, a knitted fabric having a transparent pattern was obtained, but the color was not sufficiently removed at the portion to be removed, and significant odor and smoke were generated during the heat treatment.

(Comparative Example 2) Extrusion processing was performed in the same manner as in Example 2 except that triethanolamine was used in place of the glycerin ethylene oxide 10 mol adduct of the exfoliating paste (2a). In this process, a knitted fabric having a transparent pattern was obtained, but the color was not sufficiently removed at the portion to be removed, and significant odor and smoke were generated during the heat treatment.

(Comparative Example 3) Extrusion processing was performed in the same manner as in Example 3 except that triethanolamine was used instead of the glycerin ethylene oxide 10 mol adduct of the exfoliating paste (2a). In this process, a knitted fabric was obtained, which had been processed into a watermark pattern. However, the color was not sufficiently removed at the portion to be removed, and the edge of the pattern was unclear. There has occurred.

(Example 4) On the same knitted fabric as used in Example 1, the printing paste (1) was printed in a pattern and dried at 110 ° C for 2 minutes. After that, the following disinfecting paste (2b) is printed in a pattern so as to partially overlap the printing paste (1).
Heat treatment was performed for 90 seconds in a saturated steam atmosphere at a temperature of 180 ° C. The adhesion rate of the disinfecting paste (2b) to the knitted fabric was 12 on average.
It was 0% by weight.

Glue paste (2b): glycerin ethylene oxide 10 mol adduct 12 parts by weight Fine gum NT-7P (glue) 10 parts by weight Dianix dark blue S-LF 2 parts by weight (disperse dye manufactured by Mitsubishi Kasei Hoechst) Stannous chloride 9 parts by weight Dicyandiamide (acid absorbent) 2 parts by weight Water 65 parts by weight

Thereafter, the heat-treated knitted fabric was subjected to alkali treatment at the boiling temperature for 45 minutes in the alkaline aqueous solution (3), and neutralized and dried by a conventional method. In the obtained knitted fabric, the printing paste (1) is overlapped with the printed portion (2b). The printed portion is colored with blue polyethylene terephthalate fiber and does not overlap with the printed paste (2b). In the printing paste (1), the printed area is clearly colored red, and in the printed paste (2b), the denatured polyester fiber is completely decomposed and removed, and the polyethylene terephthalate fiber remains without damage. A knitted fabric that had been etched into a sharp openwork pattern was obtained. In addition, there was no generation of offensive odor or smoke during the heat treatment.

Example 5 The same knitted fabric as used in Example 1 was immersed in the printing paste (1) and squeezed with a mangle at 110 ° C.
For 2 minutes. After that, the above-mentioned discharge paste (2b) is printed in a pattern by overlapping with the printing paste (1), and the temperature is 18 ° C.
Heat treatment was performed for 90 seconds in a saturated steam atmosphere at 0 ° C. The adhesion ratio of the printing paste (1) and the discharge paste (2b) to the knitted fabric is 2
00% by weight and an average of 120% by weight.

Thereafter, the heat-treated knitted fabric was subjected to alkali treatment at the boiling temperature for 45 minutes in the alkaline aqueous solution (3), and neutralized and dried by a conventional method. The obtained knitted fabric is printed paste (1) in the printed area, and the discharge paste (2b), the non-printed part is clearly colored red, and the discharge paste (2b) print part is made of a modified polyester fiber. Completely decomposed and removed, unmodified polyethylene terephthalate fiber colored in blue remained without damage, and a knitted fabric which had been etched into an extremely sharp openwork pattern at the time of molding was obtained. In addition, there was no generation of offensive odor or smoke during the heat treatment.

Example 6 On the same knitted fabric as used in Example 1, the printing paste (1) was printed in a pattern and dried at 110 ° C. for 2 minutes. Thereafter, the above-mentioned discharge paste (2b) is printed in a pattern shape so as to partially overlap with the printing paste (1) printing part, and the following discharge paste (2c) is further printed with the printing paste (1) printing part. And the stamping paste (2b) printing part so as to partially overlap, and 11
After drying at 0 ° C. for 2 minutes, heat treatment was performed for 90 seconds in a saturated steam atmosphere at a temperature of 180 ° C. Printing paste (1), discharge paste (2)
The adhesion rates of the b) and the disinfecting paste (2c) to the knitted fabric were respectively 120% by weight on average.

Glue paste (2c): glycerin ethylene oxide 10 mol adduct 12 parts by weight Fine gum NT-7P (glue) 10 parts by weight Stannous chloride 9 parts by weight Dicyandiamide 2 parts by weight Water 67 parts by weight

Thereafter, the heat-treated knitted fabric was subjected to alkali treatment at the boiling temperature for 45 minutes in the alkaline aqueous solution (3), and neutralized and dried by a conventional method. The obtained knitted fabric is printed paste (1) in the printed area, the paste paste (2b) and the print paste (2c), the non-printed part is clearly colored red, and the paste paste (2b) print part The modified polyester fiber is completely decomposed and removed, the unmodified polyethylene terephthalate fiber colored blue remains without damage, and the printing paste (1) is a discharge paste (2) which overlaps with the printed portion.
c) In the printed portion, the denatured polyester fiber was completely decomposed and removed, the decolorized polyethylene terephthalate fiber remained without damage, and a knitted fabric was obtained which had been etched into an extremely sharp openwork pattern at the time of molding. Also, bad odor during heat treatment,
There was no fuming.

(Comparative Example 4) Extrusion processing was performed in the same manner as in Example 4 except that triethanolamine was used instead of the glycerin ethylene oxide 10 mol adduct of the exfoliating paste (2a). In this process, a knitted fabric which was subjected to an extraction process with a watermark pattern was obtained, but the color removal at the extracted portion was insufficient, and significant odor and smoke were generated during the heat treatment.

(Comparative Example 5) Extrusion processing was performed in the same manner as in Example 5 except that triethanolamine was used in place of the 10 mol glycerin ethylene oxide adduct of the exfoliating paste (2a). In this process, a knitted fabric which was subjected to an extraction process with a watermark pattern was obtained, but the color removal at the extracted portion was insufficient, and significant odor and smoke were generated during the heat treatment.

(Comparative Example 6) The procedure of Example 6 was repeated except that triethanolamine was used in place of the 10 mol glycerin ethylene oxide adduct of the paste (2a). In this process, a knitted fabric was obtained, which had been etched into a watermark pattern.However, the shape of the mold was unclear, the color was not sufficiently removed at the extracted portion, and significant odor and smoke were generated during heat treatment. did.

[0048]

According to the present invention, the modified polyester fiber in the printed portion is completely removed without generating offensive odor, smoke or the like in the process of obtaining the exfoliated fabric, and an extremely sharp watermark pattern at the time of molding is obtained. It is possible to obtain an exfoliated cloth made of polyester fibers of the above, and also to significantly reduce damage to unmodified polyester fibers, thereby processing an exfoliated cloth with extremely low strength as a cloth and extremely few yarn breakage. It is possible to obtain with good stability.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI D06P 3/34 D06P 3/34 5/00 120 5/00 120D D06Q 1/02 D06Q 1/02 (72) Inventor Hiromi Hounaga Aichi 1-60, Sunadabashi, Higashi-ku, Nagoya-shi, Japan Mitsubishi Rayon Co., Ltd. Product Development Laboratory (56) References JP-A-55-90673 (JP, A) JP-A-5-98587 (JP, A) JP-A-6 -212582 (JP, A) JP-A-8-218280 (JP, A) JP-A-5-263375 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D06P 5/13 D06P 5/00 120 D06Q 1/02

Claims (3)

(57) [Claims] 1. A method for producing an exfoliated polyester fiber fabric comprising the following steps. (B) a step of coloring at least a part of a fabric comprising a modified polyester fiber and an unmodified polyester fiber containing a third component as a copolymerization component and ethylene terephthalate as a main repeating unit with a ground dye, (b) polyhydric alcohol ethylene oxide (C) a step of performing a heat treatment at a temperature of 100 to 240 ° C. (d) an alkali treatment and a printing section For removing the modified polyester fiber and removing the ground dye of the unmodified polyester fiber in the printed area 2. In the step (b), a disinfecting paste containing a polyhydric alcohol ethylene oxide adduct and a dye decomposing agent containing a dye decomposing agent in the disinfecting paste and a dye resistant to alkali treatment. The method for producing a discharge-treated polyester fiber fabric according to claim 1, wherein a color paste is used. 3. In the step (b), a discharge paste containing a polyhydric alcohol ethylene oxide adduct and a dye decomposer and containing no dye, a dye decomposer in the discharge paste, 2. A method for producing a discharge-processed polyester fiber cloth according to claim 1, wherein a discharge-resistant paste containing a dye resistant to alkali treatment is used.