JPH11106675A - Basic dye composition and dyeing using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition hardly causing pollution to human body such as fingers of worker, dyeing and coloring pollution to fibers other than basic dye-dyeable type synthetic fiber and excellent in compatibility with other kinds of dyes by including a thiazol-based blue basic dye and a specific anion dispersant. SOLUTION: This basic dye composition is obtained by including one or more kinds of anionic dispersant selected from (A) 1,3,4-thiadiazole-based blue basic dye [preferably a compound or the like of the formula (R1 and R2 are each H, a 1-4C alkyl or the like; R3 is a 1-4C alkyl; R4 and R5 are each H, a 1-4C alkyl or the like; R6 and R7 are each H, a 1-4C alkyl or the like; X<-> is an anion)] and (B) one or more anion dispersants selected from formalin condensate of naphthalenesulfonic acid, formalin condensate of an alkylnaphthalene-sulfonic acid, ligninsulfonic acid and polystyrenesulfonic acid, preferably at a ratio of 1-5 pts.wt. component B to 1 pt.wt. component A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a water-soluble 1,3,4-
The present invention relates to a basic dye composition containing a thiadiazole-based blue basic dye and an anionic dispersant, and a method of dyeing a synthetic fiber mixed with a basic dye-dyeable synthetic fiber and another fiber using the same, and dyeing a cross-woven fiber.

[0002]

2. Description of the Related Art Water-soluble basic dyes are generally used in the form of powders or liquids, and, in some cases, admixed with auxiliaries or solid diluents, to form CDP fibers (basic dye-dyeable synthetic fibers; Polyester fibers) and polyacrylonitrile fibers, which are often used for robust and clear dyeing. However, due to the large contamination of the human body and equipment, and other dye species in one-bath dyeing of blended and mixed fibers. For example, various drawbacks have been pointed out, such as poor compatibility with disperse dyes, acid dyes, direct dyes, and reactive dyes.

[0003]

In dyeing a blended fiber or a woven fiber, contamination to fibers other than CDP fiber and acrylonitrile fiber is improved, and contamination to the human body and equipment is small, and other anionic species are used. It is desired to develop a basic dye composition having excellent compatibility with the genus dyes, particularly, a blue color which is particularly versatile.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned conventional disadvantages, and as a result, have accomplished the present invention. That is, the present invention

(1) 1,3,4-thiadiazole-based blue basic dye (A), selected from a formalin condensate of naphthalenesulfonic acid, a formalin condensate of alkylnaphthalenesulfonic acid, ligninsulfonic acid and polystyrenesulfonic acid A basic dye composition containing at least one or more anionic dispersants (B);
The 4-thiadiazole blue basic dye (A) is represented by the formula (1)

[0006]

Embedded image

(In the formula (1), R ₁ and R ₂ are each independently a hydrogen atom, a linear or branched, unsubstituted or hydroxy group, a cyano group, and a group having 1 to 4 carbon atoms. Represents an acyloxy group, an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 8 carbon atoms substituted with an alkoxycarbonyl group having 1 to 4 carbon atoms, and R ₃ represents 1 to 4 carbon atoms.
R ₄ and R ₅ each independently represent a hydrogen atom, a linear or branched, unsubstituted or hydroxy group, a chlorine atom, a cyano group, a carbon number of 1 to
4 alkoxy groups, an acyloxy group having 1 to 4 carbon atoms, an alkoxycarbonyloxy group having 1 to 4 carbon atoms,
Represents an alkyl group having 1 to 4 carbon atoms substituted with an aryloxy group, an allyloxy group, a phenyl group or a benzoyloxy group, wherein R ₆ and R ₇ are each independently a hydrogen atom,
It represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a halogen atom, and X ⁻ represents an anion. (3) R ₁ and R ₂ are each an isopropyl group, R ₃ , R ₄ and R ₅ are each a methyl group, R ₆ and R ₇ Is a basic dye composition of (1) or (2), each of which is a hydrogen atom; and (4) any of (1) to (3), wherein the anionic dispersant (B) is a formalin condensate of naphthalenesulfonic acid. The basic dye composition according to claim 1, (5)
1,3,4-thiadiazole blue basic dye (A) 1
The basic dye composition according to any one of (1) to (4), wherein the basic dye composition contains 1 to 5 parts by weight of an anionic dispersant (B) based on part by weight, and (6) a dyeable synthetic fiber of a basic dye. When dyeing a single fiber or a mixed fiber of a basic dye-dyeable synthetic fiber and another fiber, the basic dye composition according to any one of (1) to (5) is used alone or in another species. A dyeing method characterized by being used in combination with a dye.

[0008]

DETAILED DESCRIPTION OF THE INVENTION Formula (1) used in the present invention
In the compounds represented by, R ₁ and R ₂ independently represent hydrogen or a linear or branched, unsubstituted or substituted alkyl group having 1 to 8 carbon atoms, and specific examples thereof include a methyl group, Ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-
Butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, isohexyl, 2-ethylhexyl, heptyl, n-
Octyl group, isooctyl group, tert-octyl group,
2-hydroxyethyl group, 2-hydroxypropyl group, 2
-Methoxyethyl group, 2-ethoxyethyl group, 2-butoxyethyl group, 2- (isobutoxy) -ethyl group, γ-
Methoxybutyl group, 2-cyanoethyl group, 2- (methoxycarbonyl) ethyl group, 2- (butoxycarbonyl)
Examples include an ethyl group, a 2-acetoxyethyl group, a 2- (propionyloxy) ethyl group, and a 2- (butyryloxy) ethyl group.

R ₃ represents an alkyl group having 1 to 4 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group and a tert- Butyl group and the like.

R ₄ and R ₅ are each independently hydrogen, straight-chain or branched and have no substituent or a hydroxy group, a chlorine atom, a cyano group, an alkoxy group having 1 to 4 carbon atoms, 1 to 4 acyloxy groups, an alkoxycarbonyloxy group having 1 to 4 carbon atoms, an aryloxy group,
Represents an alkyl group having 1 to 4 carbon atoms which may be substituted by an allyloxy group, a phenyl group or a benzoyloxy group, and specific examples thereof include a 2-hydroxyethyl group and a 2-hydroxyethyl group.
Hydroxypropyl group, 2-chloroethyl group, 2-cyanoethyl group, 2-methoxyethyl group, 2-ethoxyethyl group, 2-butoxyethyl group, 2- (isobutoxy) ethyl group, γ-methoxybutyl group, 2-acetoxyethyl group , 2- (propionyloxy) ethyl group, 2- (butyryloxy) ethyl group, 2- (methoxycarbonyl) ethyl group, 2- (butoxycarbonyl) ethyl group, 2-phenoxyethyl group, 2-allyloxyethyl group, benzyl Group, phenethyl group, 3-phenylpropyl group, 2-benzoyloxyethyl group and the like.

R ₆ and R ₇ each independently represent hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a halogen atom. Group, n-propyl group, isopropyl group, n-
A butyl group, sec-butyl group, tert-butyl group, methoxy group, ethoxy group, propoxy group, butoxy group, fluorine atom, bromine atom or chlorine atom are employed.

As a preferable combination of these substituents, for example, R ₁ and R ₂ are each an isopropyl group, R ₃ , R ₄ and R ₅ are each a methyl group, and R ₆ and R ₇ are each a hydrogen atom.

X ^- represents an anion, and a suitable colorless organic or inorganic anion can be used as a suitable anion. Examples of the inorganic anions include halogen ions such as fluorine ions, chloride ions, bromine ions, and iodine ions, perchlorate ions, tetrafluoroborate ions, hydroxide ions, sulfite ions, sulfate ions, dihydrogen phosphate ions, and phosphate ions. Ion, bicarbonate ion, carbonate ion,
Examples include methyl sulfate ion, ethyl sulfate ion, cyanate ion, thiocyanate ion, trichlorozincate ion, tetrachlorozincate ion and the like. As the organic anion, for example, a saturated or unsaturated aliphatic, alicyclic, aromatic or heteroaromatic carboxylate ion and sulfonate ion, for example, formate ion, acetate ion, hydroxyacetate ion, oxalate ion , Citrate, lactate, tartrate, cyclohexanecarboxylate, phenylacetate, benzoate, nicotinate, methanesulfonate, ethanesulfonate, benzenesulfonate, chlorobenzenesulfonate, chlorobenzenesulfonate, toluenesulfone Acid ions and hexafluorosilicate ions.

Preferred examples of these anions include methyl sulfate ion, ethyl sulfate ion and the like. Incidentally, the anion is polyvalent anion, in a case such as sulfuric acid or oxalic acid anion formula (1) X ^-
Represents one equivalent of such a polyvalent anion.

Next, Table 1 shows typical examples of the basic dye represented by the formula (1). In the table, Ph means a phenyl group.

[0016]

Table 1 Table 1 Compound No. R ₁ R ₂ R ₃ R ₄ R ₅ R ₆ R ₇ X ^- 1. iso-C3H7 iso-C3H7 CH3 CH3 CH3 HH CH3SO4 2. iso-C3H7 iso-C3H7 CH3 C2H5 C2H5 HH CH3SO4 3. iso-C3H7 iso-C3H7 CH3 C2H4OH CH3 HH CH3SO4 CH3 CH3 CH3 n-C4H9 n-C4H9 CH3 H CH3SO4 CH3 CH3 C2H5 CH3 CH3 ClH CH3SO4 6. 6. C2H5 C2H5 CH3 C2H5 C2H4-Ph HHCl 7. C2H5 C2H5 CH3 C2H4OH CH3 OCH3 HCl 8. C2H5 C2H5 CH3 C4H9 C4H9 CL HC1 n-C4H9 n-C4H9 C2H5 CH3 CH3 HHCl 10. n-C4H9 n-C4H9 C2H5 C2H5 C2H4-Ph HH Cl

The basic dye represented by the formula (1) of the present invention is known, and can be produced, for example, by the method described in JP-B-58-49578.

The anionic dispersant (B) used in the present invention
Is selected from a formalin condensate of naphthalenesulfonic acid, a formalin condensate of alkylnaphthalenesulfonic acid, ligninsulfonic acid and polystyrenesulfonic acid. These anionic dispersants are usually available commercially. For example, examples of the formalin condensate of naphthalenesulfonic acid include Demol N and Demol RN (both manufactured by Kao Corporation). As the alkyl group of the formalin condensate of alkylnaphthalenesulfonic acid used in the present invention, methyl, ethyl, propyl, and butyl groups are applied, and methyl and butyl groups are particularly preferable.
Further, formalin condensate of naphthalene sulfonic acid, formalin condensate of alkyl naphthalene sulfonic acid, lignin sulfonic acid or polystyrene sulfonic acid is usually used in the form of an alkali metal salt such as sodium or potassium, or an ammonium salt. Can be

The basic dye composition of the present invention comprises 1,3,4
At least one anionic dispersant (B) selected from thiadiazole blue basic dye (A) powder and formalin condensate of naphthalenesulfonic acid, alkylnaphthalenesulfonic acid, formalin condensate, ligninsulfonic acid or polystyrenesulfonic acid; The powder may be produced by simply mixing the powder with the powder, but a production method in which both are usually dissolved in water and mixed is preferable.

A method of dissolving the 1,3,4-thiadiazole-based blue basic dye (A) and the anionic dispersant (B) in water and mixing them will be described. In producing the composition of the present invention, the basic dye (dry product) is first weight ratio of 1 to 1.
5 times, preferably 2.5 to 4 times formalin condensate of naphthalene sulfonic acid and / or formalin condensate of alkyl naphthalene sulfonic acid and / or aqueous solution of lignin sulfonic acid and / or polystyrene sulfonic acid (usually 10 to 50 wt. % Aqueous solution), preferably by adding an acid agent sufficient to maintain acidity to make the pH acidic, preferably pH
Adjust to 6 or less. On the other hand, a powder of a water-soluble basic dye or a press cake is suspended in water with stirring to form a fluid slurry having a solid content of 5 to 40%, and an acid agent is added to the slurry to adjust the pH to acidic. Preferably, the pH is kept at 6 or less. When the acidic slurry of the dye thus prepared and a formalin condensate of naphthalenesulfonic acid and / or a formalin condensate of alkylnaphthalenesulfonic acid and / or an aqueous acidic solution of ligninsulfonic acid and / or polystyrenesulfonic acid are mixed with stirring, once, Although a poorly soluble basic dye complex is formed, water solubility or fine dispersing starts immediately with excess naphthalenesulfonic acid, formalin condensate of alkylnaphthalenesulfonic acid, ligninsulfonic acid or polystyrenesulfonic acid. In order to complete the water-solubilization more quickly, the solution is heated to about 50 to 60 ° C. to complete the water-solubilization to obtain the desired aqueous basic dye composition. ,
For example, a powdery dye composition can be obtained by spray drying, hot air drying in a tray, or the like. The method of mixing the basic dye and the formalin condensate is the same as the method described above, except that the formalin condensate of naphthalenesulfonic acid and / or the formalin condensate of alkylnaphthalenesulfonic acid and / or A method of adding an aqueous solution or powder of ligninsulfonic acid and / or polystyrenesulfonic acid, a formalin condensate of naphthalenesulfonic acid and / or a formalin condensate of alkylnaphthalenesulfonic acid and / or an aqueous solution of ligninsulfonic acid and / or polystyrenesulfonic acid It is also possible to add a wet cake or powder of the dye therein. In these cases, the same pH, amount and concentration can be applied.

The acid agent that may be used in the above method is
Regardless of inorganic acids, organic acids, solid acids, and liquid acids, ordinary water-soluble hydrogen ion supply substances can be used. For example, sulfuric acid, hydrochloric acid, mineral acids such as nitric acid and acetic acid, oxalic acid, maleic acid, fumaric acid, citric acid, malic acid, ascorbic acid,
Organic acids such as lactic acid, tartaric acid and succinic acid are employed.

Examples of the dyeing method using the basic dye composition of the present invention include ordinary fiber dyeing methods such as dip dyeing, printing and padding dyeing. In the basic dye composition of the present invention, the basic dye and the anionic dispersant are ionically bonded to form an essentially poorly soluble complex salt, which is dispersed or dispersed by the force of the excess anionic dispersant. Although it is solubilized, this complex salt is gradually decomposed in the dyeing bath as the temperature rises, and only the basic dye of the substrate is adsorbed on the fiber,
The leveling properties are remarkably good, so that commonly used leveling agents are not necessarily required. In addition, since basic dyes are usually easy to form a water-insoluble complex with anionic dyes, dyeing basic dye-stainable synthetic fibers or mixed fibers of basic dye-stainable synthetic fibers and other fibers in dyeing is essential. Although there was a problem with the combination with an anionic dye, the use of the basic dye composition of the present invention makes it impossible to use the dye together with the basic dye, for example, one-bath dyeing with an acid, dispersion or direct dye. Is also possible. Furthermore, in printing or padding dyeing, the compatibility with the sizing agent having an anionic group is also good, and a dissolving agent is not required when adjusting a high-concentration dye bath, so that the operation required for dye bath adjustment is extremely easy. it can. Furthermore, there is a feature that contamination of equipment such as a dyeing pot and staining of a human body such as a finger of an operator are small.

[0023]

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” and “%” indicate “parts by weight” and “% by weight”, respectively.

Example 1 Compound no. Water 91 was added to 202 parts of the dried product of 1 basic dye.
7 parts were added and mixed well to form a slurry. Acetic acid was added to the slurry to adjust the pH to 6 or less. The slurry was added with stirring to 929 parts of an aqueous solution prepared by dissolving 401 parts of a sodium salt of a formalin condensate of naphthalenesulfonic acid and adjusting the pH to 6 or less with acetic acid to obtain a complex salt slurry. The complex salt slurry was further heated to 65 ° C. and stirred for 3 hours to obtain a completely water-soluble liquid blue basic dye composition. The liquid product was spray-dried to obtain 535 parts of a dried blue basic dye composition. Dyeing contamination of the human body such as a finger of an operator of the composition is as follows.
Compound No. The improvement was remarkably improved as compared with the basic dye 1 alone.

Example 2 Compound No. Water 91 was added to 202 parts of the dried product of 1 basic dye.
7 parts were added and mixed well to form a slurry. Acetic acid was added to the slurry to adjust the pH to 6 or less. The slurry was added with stirring to 929 parts of an aqueous solution prepared by dissolving 401 parts of a sodium salt of a formalin condensate of alkylnaphthalenesulfonic acid and adjusted to pH 6 or less with acetic acid to obtain a complex salt slurry. The complex salt slurry was further heated to 65 ° C. and stirred for 3 hours to obtain a completely water-soluble liquid blue basic dye composition. The liquid product was spray-dried to obtain 535 parts of a dried blue basic dye composition. The staining of the human body such as a finger of an operator by the composition was confirmed by Compound No. The improvement was remarkably improved as compared with the basic dye 1 alone.

Example 3 Compound No. Water 91 was added to 202 parts of the dried product of 1 basic dye.
7 parts were added and mixed well to obtain a slurry. This slurry was added with stirring to 929 parts of an aqueous solution in which 401 parts of ligninsulfonic acid was dissolved to obtain a complex salt slurry.
The complex salt slurry was further heated to 65 ° C. and stirred for 3 hours to obtain a completely water-soluble liquid blue basic dye composition. The liquid product was spray-dried to obtain 535 parts of a dried blue basic dye composition. Dyeing contamination of the human body such as a finger of an operator of the composition is as follows.
Compound No. The improvement was remarkably improved as compared with the basic dye 1 alone.

Example 4 Compound no. Water 91 was added to 202 parts of the dried product of 1 basic dye.
7 parts were added and mixed well to obtain a slurry. This slurry was added with stirring to 929 parts of an aqueous solution in which 401 parts of polystyrene sulfonic acid was dissolved to obtain a complex salt slurry. The complex salt slurry was further heated to 65 ° C. and stirred for 3 hours to obtain a completely water-soluble liquid blue basic dye composition. The liquid product was spray-dried to obtain 535 parts of a dried blue basic dye composition. The staining of the human body such as a finger of an operator by the composition was confirmed by Compound No. The improvement was remarkably improved as compared with the basic dye 1 alone.

Example 5 1 part of the basic dye composition prepared in Example 1 was adjusted to pH 4 with acetic acid and sodium acetate in the usual manner to adjust the pH to 4, and the dyeing water was 500 parts.
The solution was dissolved in 0 parts to prepare a dye bath. 100 parts of CDP fiber cloth was immersed in this at 60 ° C., heated to 120 ° C. in 30 minutes, and dyed at the same temperature for 60 minutes. This was washed with water to obtain a uniformly dyed blue dyed product. There was no contamination of the stainless steel staining pot.

Example 6 A dye bath was prepared by dissolving 1 part of the basic dye composition prepared in Example 1 in 5000 parts of dyeing water whose pH was adjusted to the value shown in Table 2 with acetic acid and sodium acetate in a conventional manner. did. This is C
100 parts of a cross-woven cloth of DP and polyester (woven with a ratio of CDP and polyester of 80:20 and streaked) is 60 parts
Immersion at 120 ° C., heated to 120 ° C. in 30 minutes, and
It was stained for 0 minutes and washed with water. The staining results are shown in Table 2 below.

Example 7 1 part of the basic dye composition prepared in Example 3 was adjusted to pH 4 with acetic acid and sodium acetate in a conventional manner to adjust the pH to 4, and the dyeing water was 500 parts.
The solution was dissolved in 0 parts to prepare a dye bath. 100 parts of a cloth of polyacrylonitrile fiber is immersed in this at 60 ° C.
The temperature was raised to 00 ° C, dyed at the same temperature for 60 minutes, and washed with water. A clear blue dyeing was obtained.

Example 8 2 parts of the basic dye composition prepared in Example 2 was dissolved in 10 parts of water. On the other hand, Kayanol milling blue BW
2 parts (acid dye made by Nippon Kayaku) were dissolved in 20 parts of hot water. These were added to 1 part of glacial acetic acid in 6000 parts of water to prepare a dye bath. At 60 ° C., 100 parts of an acrylonitrile: wool (50:50) blended yarn was immersed, heated to 100 ° C., and dyed for 60 minutes. There was no tarling during the dyeing, and a uniform blue dyed product was obtained in which both fibers were dyed dark.

Example 9 0.8 parts of the basic dye compound prepared in Example 2 and 0.02 parts of Kayalon polyester light yellow 5GS (Nippon Kayaku disperse dye) were added to acetic acid and acetic acid in a conventional manner. The solution was dissolved in 180 parts of dyeing water adjusted to pH 4 with soda to prepare a dye bath. In addition, a cross-woven cloth of CDP and polyester (C
4 parts of a fiber woven with a ratio of DP and polyester of 80:20 were immersed at 60 ° C., heated to 130 ° C. for 60 minutes, dyed at the same temperature for 60 minutes, and washed with water. There is no tarling during staining, and the CDP part is uniformly stained blue.
The polyester part was dyed a vivid yellow. Contamination of the polyester portion of the composition is very small and negligible.

Comparative Example 1 Representative water-soluble basic dye I. Basic Blue 5
4 (benzothiazole) was made water-soluble or finely dispersed in the same manner as in Example 1 to obtain a basic dye composition. This composition was dyed in the same manner as in Example 6 onto a cross-woven cloth of CDP and polyester (the ratio of CDP and polyester woven in a streak of 80:20). Table 2 shows the results.

[0034]

[Table 2] Table 2 pH Example 6 Comparative Example 1 5.5 ○ × 4 ○ × 3.5 ○ △

：: No contamination in polyester portion Δ: Slight reddish contamination in polyester portion X: Reddish contamination was noticeable in polyester portion

As is evident from Table 2, the CDP portion of the material to be dyed using the basic dye composition of the present invention is uniformly dyed blue, and the polyester portion is left with streaks and white stains are observed. Did not. On the other hand, the CDP portion of the material to be dyed using the basic dye composition of Comparative Example 1 was uniformly dyed blue, but the polyester portion was stained reddish, though the degree of contamination varied depending on the pH. .

[0037]

EFFECT OF THE INVENTION The blue basic dye composition obtained according to the present invention has low contamination of the human body such as a worker's finger and staining of dyeing equipment, is excellent in compatibility with other kinds of dyes, and is a basic dye dyeable fiber. There is an advantage that coloring contamination to other fibers, especially polyester, is small. In addition, since the dye has a high exhaustion property, dyeing can be performed stably and economically.

Claims (6)

[Claims] 1. A 1,3,4-thiadiazole blue basic dye (A), selected from a formalin condensate of naphthalenesulfonic acid, a formalin condensate of alkylnaphthalenesulfonic acid, ligninsulfonic acid and polystyrenesulfonic acid. A basic dye composition containing at least one or more anionic dispersants (B). 2. The 1,3,4-thiadiazole blue basic dye (A) is represented by the formula (1): ## STR1 ## (In the formula (1), R ₁ and R ₂ are each independently a hydrogen atom,
Straight or branched, unsubstituted or hydroxy, cyano, C1-4 acyloxy, C1-4 alkoxy or C1-4
1 to 8 carbon atoms substituted with two alkoxycarbonyl groups
R ₃ represents an alkyl group having 1 to 4 carbon atoms, and R ₄ and R ₅ independently of one another are a hydrogen atom, a straight-chain or branched-chain, and have no substituent or Hydroxy group, chlorine atom, cyano group, alkoxy group having 1 to 4 carbon atoms, acyloxy group having 1 to 4 carbon atoms, 1 carbon atom
Represents an alkyl group having 1 to 4 carbon atoms substituted by 1 to 4 alkoxycarbonyloxy groups, aryloxy groups, allyloxy groups, phenyl groups or benzoyloxy groups, and R ₆ and R ₇ independently represent a hydrogen atom , Having 1 to 1 carbon atoms
X represents an alkyl group, an alkoxy group having 1 to 4 carbon atoms or a halogen atom, and X ⁻ represents an anion. The basic dye composition according to claim 1, which is a basic dye represented by the formula (1): 3. R ₁ and R ₂ are each an isopropyl group,
R ₃ , R ₄ and R ₅ are each a methyl group, R ₆ and R ₇
The basic dye composition according to claim 1 or 2, wherein each is a hydrogen atom. 4. The basic dye composition according to claim 1, wherein the anionic dispersant (B) is a formalin condensate of naphthalenesulfonic acid. 5. An anion dispersant (B) 1 to 1,3,4-thiadiazole blue basic dye (A) per 1 part by weight.
The basic dye composition according to any one of claims 1 to 4, which contains 5 parts by weight. 6. The base according to any one of claims 1 to 5, when dyeing a basic dye-dyeable synthetic fiber alone or a mixed fiber of a basic dye-dyeable synthetic fiber and another fiber. A dyeing method, comprising using a dyestuff composition alone or in combination with another kind of dyestuff.