Black direct dyes and their compositions, preparation methods and uses

Abstract

A black direct dye, a black direct dye composition, a preparation method and uses thereof. The black direct dye has a structure shown in formula (I). The black direct dye of the present invention has excellent dyeing performance, and has excellent comprehensive effects such as washing resistance, perspiration resistance, rubbing resistance and color fastness to light. Its quality is stable, enriching the black direct dye market. #imgabs0#In formula (I), R1, R3, R4 and R6 are each independently -NH2 or -OH; R2 and R5 are each independently -H or -SO3Na; and the compound shown in formula (I) does not include the compound of the following formula (Ia), #imgabs1#

Description

Technical Field:

[0001] The present invention belongs to the field of dye synthesis, and particularly relates to a black direct dye and its composition, as well as a preparation method and use of the black direct dye, belonging to the field of dyes and their synthesis. Technical Background:

[0002] China is a major producer of direct dyes. Direct dyes can be applied to the dyeing of various materials (including cellulose fibers, protein fibers, cotton, wool, linen, etc.) fabrics, and have a wide range of applications. In addition to being used for fabric dyeing, black direct dyes can also be used as inks and account for a large proportion in the market.

[0003] At present, the types of black direct dyes disclosed in the market are few. Therefore, in order to fill the market gap, it has become an urgent technical problem to study a black direct dye with high light fastness and good color fastness properties. Summary of the Invention:

[0004] The present invention aims to provide a black direct dye with excellent comprehensive effects such as washing fastness, perspiration fastness, rubbing fastness, light fastness and color fastness.

[0005] In view of this, in the first aspect of the present invention, there is provided a black direct dye having the structure shown in formula (I).

[0006]

[0007] In formula (I), R1, R3, R4 and R6 are each independently -NH2 or -OH; R2 and R5 are each independently -H or -SO3Na.

[0008] And the compound shown in formula (I) does not include the compound of the following formula (Ia).

[0009]

[0010] Optionally, the black direct dye of the present invention is selected from the compounds of the following formula (I-1)-(I-22):

[0011]

[0012]

[0013]

[0014] In the second aspect of the present invention, there is provided a black direct dye composition, which comprises two or more compounds of the above black direct dye and optionally a compound of formula (Ia).

[0015] In the third aspect of the present invention, there is provided a method for preparing the above-mentioned black direct dye or black direct dye composition, which comprises the following steps:

[0016] Step 1): Subject a p-nitroaniline solution to a diazotization reaction with a nitrite solution to obtain a diazotization product A; the reaction equation is as follows:

[0017]

[0018] Step 2): Couple the diazotization product A obtained in Step 1) with an H-acid solution to obtain a coupling product B; the reaction equation is as follows:

[0019]

[0020] Step 3): Reduce the coupling product B obtained in Step 2) to obtain a black base solution C; the reaction equation is as follows:

[0021]

[0022] Step 4): Subject the black base solution C to a diazotization reaction with a nitrite solution to obtain a diazotization product D; the reaction equation is as follows:

[0023]

[0024] Step 5): Couple the diazotization product D in Step 4) with a coupling component solution F of the following formula (I') and / or (I'') to obtain the liquid black direct dye shown in formula (I):

[0025]

[0026] Wherein, in formula (I') and (I''), R1, R2, R3, R4, R5 and R6 are as defined in the first aspect above;

[0027] The reaction gives the following compound:

[0028]

[0029] Step 1):

[0030] Optionally, in Step 1), the nitrite solution is added to the p-nitroaniline solution and the reaction is carried out under acidic conditions;

[0031] Optionally, when adding, the temperature of the p-nitroaniline solution is maintained at -5 to 5 °C, and the adding time is 5 - 10 minutes.

[0032] Optionally, the reaction temperature in Step 1) is -5 to 5 °C, the reaction time is 1.5 - 3 hours, preferably 2 hours;

[0033] For the nitrite solution in step 1), the nitrite can be dissolved in a solvent to obtain the nitrite solution. For the solvent, the present invention is not particularly limited and can be a polar solvent commonly used in the art, such as water. Specifically, in order to obtain a nitrite solution with a suitable concentration, 5-10 parts by weight of nitrite can be dissolved in 15-80 parts by weight of water, and stirred to obtain an aqueous nitrite solution.

[0034] In the present invention, the nitrite is not particularly limited and can be some nitrites commonly used in the art. For example, the nitrite can be some commonly used nitrites such as sodium nitrite, potassium nitrite, lithium nitrite, etc.

[0035] The p-nitroaniline solution of the present invention can be obtained by dissolving p-nitroaniline in a solvent. For the solvent, the present invention is not particularly limited and can be a polar solvent commonly used in the art, such as water.

[0036] In some specific embodiments, while obtaining the p-nitroaniline solution, a part of the acid solution can be added to the p-nitroaniline solution and then pulped, and then the slurry is cooled so that the diazotization reaction in step 1) is carried out under acidic conditions.

[0037] Specifically, in order to obtain a p-nitroaniline solution with a suitable concentration, 1-10 parts by weight of p-nitroaniline can be dissolved in 10-85 parts by weight of water to obtain a p-nitroaniline solution. Then, 5-15 parts by weight of the acid solution is added to the p-nitroaniline solution and then pulped, and then the slurry is cooled so that the diazotization reaction in step 1) is carried out in the presence of the acid solution.

[0038] Optionally, the pulping time after adding the acid solution is 1.5-2 hours, and the temperature after cooling is -3-3°C. For cooling, any feasible cooling method in the art can be used. As a preference for more rapid cooling, the present invention can use ice cubes for cooling. Specifically, the addition amount of ice cubes can be 50-90 parts by weight.

[0039] Furthermore, for the acid solution, the present invention is not particularly limited and can be some acid solutions commonly used in the art, such as sulfuric acid, hydrochloric acid, etc. In the present invention, considering the purity of the product, etc., hydrochloric acid is preferably used as the acid solution.

[0040] In addition, when adding the nitrite solution to the p-nitroaniline solution, the Congo red test paper remains bright blue, and at the same time, the addition rate needs to be controlled to make the starch potassium iodide test paper slightly blue. If the starch potassium iodide does not turn blue, the acid solution and the nitrite solution are added.

[0041] In some more specific embodiments, generally during the reaction, the nitrite solution may be in excess. At this time, the excess nitrous acid should be removed to prevent the generation of excessive impurities. Specifically, p-nitroaniline solution can be used to remove the excess nitrous acid. Further, the addition amount of the p-nitroaniline solution is not particularly limited in the present invention and can be added according to the amount of nitrous acid. Preferably, in the present invention, a small amount of p-nitroaniline solution can be added to remove the excess nitrous acid, and after the addition, the diazonium product A is obtained.

[0042] Step 2):

[0043] Optionally, step 2) is to add the H-acid solution to the diazonium product A for reaction.

[0044] For H-acid, its Chinese name is also 1-amino-8-naphthol-3,6-disulfonic acid, and its molecular formula is C 10 H9NO7S2, with a molecular weight of 319.31. The H-acid solution of the present invention can be obtained by dissolving H-acid in a solvent. The solvent is not particularly limited in the present invention and can be a commonly used polar solvent in the art, such as water. In addition, in order to obtain an H-acid solution with a suitable pH value, an alkaline substance can be used to adjust the pH value. Preferably, the alkaline substance can be liquid alkali (i.e., sodium hydroxide), lithium hydroxide, potassium hydroxide, baking soda, soda ash, etc.

[0045] In some specific embodiments, in order to obtain an H-acid solution with a suitable concentration, 1-15 parts by weight of the H-acid solution can be dissolved in 50-195 parts by weight of water, slurried and stirred, and then the pH value can be adjusted with an alkaline substance. First, a part of the alkaline substance can be used to adjust the pH value to 5.5-7, and then 2-50 parts by weight of the alkaline substance can be added to obtain the H-acid solution. In the present invention, there is no requirement for the alkaline substance as long as the pH value is 5.5-7, and baking soda is preferred.

[0046] For the H-acid solution, it still needs to be cooled. Preferably, the temperature of the H-acid solution is 5-10 °C.

[0047] Further, in order to enable the reaction to proceed effectively and completely, in step 2), the H-acid is added dropwise to the diazonium product solution, the dropping temperature is 5-8 °C, and the pH of the mixed solution after dropping is 1.5-6.

[0048] In addition, for the reaction conditions in step 2), the present invention is not particularly limited as long as the coupling product can be prepared. In some more specific embodiments, the reaction temperature in step 2) is 5-8 °C, and the reaction time is 8-10 hours.

[0049] Step 3):

[0050] For the reducing agent solution in step 3), the reducing agent can be dissolved in a solvent to obtain the reducing agent solution. Regarding the solvent, the present invention is not particularly limited, and it can be a polar solvent commonly used in the art, such as water, etc. Specifically, in order to obtain a reducing agent solution with a suitable concentration, 5-10 parts by weight of the reducing agent can be dissolved in 15-80 parts by weight of water, and stirred to obtain an aqueous reducing agent solution.

[0051] In the present invention, the reducing agent is not particularly limited, and it can be some reducing agents commonly used in the art with reducing properties between nitro and nitroso. For example, the reducing agent can be sulfide alkali, polysulfide sodium, ferrous salt, low-valent oxide, and non-metal hydride, etc., and preferably sodium sulfide, polysulfide sodium, or ferrous salt;

[0052] In the present invention, the reduction reaction in step 3) is obtained by adding the reducing agent solution to the coupling product for reaction; after adding, the reaction conditions are not particularly limited, as long as the reduction reaction can be carried out to obtain the black base. In some specific embodiment schemes, in order to make the reaction effective and complete, the reaction temperature is 35-40 °C, and the reaction time is 2-5 hours.

[0053] Step 4):

[0054] In step 4), the present invention performs a diazotization reaction again by continuously dropping a nitrite solution into the black base to obtain a diazotized product D.

[0055] For the nitrite solution in step 4), the nitrite can be dissolved in a solvent to obtain the nitrite solution. Regarding the solvent, the present invention is not particularly limited, and it can be a polar solvent commonly used in the art, such as water, etc. Specifically, in order to obtain a nitrite solution with a suitable concentration, 10-20 parts by weight of the nitrite can be dissolved in 20-40 parts by weight of water, and stirred to obtain an aqueous nitrite solution. Specifically, the dropping temperature of the nitrite solution is 5-10 °C.

[0056] Further, the nitrite solution is dropped into the black base. After the nitrite solution is dropped into the black base, the pH value of the solution can be appropriately adjusted as needed to maintain the pH value at 10-11, and then an acid solution is added and stirred, and a heat preservation reaction is carried out until the reaction end point is reached to obtain the diazotized product D.

[0057] Further, after the sodium nitrite solution is added to the black base, if the pH value of the system < 7.0, the pH value is adjusted with an alkaline substance. Preferably, the alkaline substance can be liquid alkali (i.e., sodium hydroxide), lithium hydroxide, potassium hydroxide, baking soda, soda ash, etc.; if the pH value of the system > 13.0, the pH value is adjusted with an acidic substance. Preferably, the acidic substance can be hydrochloric acid, sulfuric acid, etc.

[0058] Further, an acid solution can be added to the black nitrite solution, and a cooling treatment is carried out. Specifically, for the acid solution, the present invention does not make any special limitation thereto, and it can be some acid solutions commonly used in the art, such as sulfuric acid, hydrochloric acid, etc. In the present invention, hydrochloric acid is preferably used as the acid solution. For cooling, any feasible cooling method in the art can be adopted. For more rapid cooling, preferably, the present invention can use ice cubes for cooling.

[0059] Further, 5 - 100 parts of the acid solution are dissolved in the black sodium nitrite mixed solution in step 4), stirred evenly, and then ice cubes are added for cooling; after the reaction is completed, an excess of nitrous acid is eliminated by sulfamic acid to obtain the diazo product D.

[0060] In addition, for the reaction conditions in step 4), the present invention does not make any special limitation, as long as the diazo product can be prepared. In some specific embodiments, the reaction temperature in step 4) is 3 - 5 °C, and the reaction time is 5 - 7 hours.

[0061] Step 5 :

[0062] Optionally, in step 5), a coupling component solution F containing the formula (I') and / or (I'') is added to the diazotization product D for reaction;

[0063] The coupling component of the formula (I') and / or (I'') can be dissolved in a solvent to obtain a coupling component solution F containing the formula (I') and / or (I''). For the solvent, the present invention does not make any special limitation, and it can be a polar solvent commonly used in the art, such as water.

[0064] In addition, in order to obtain a coupling component solution F with a suitable pH value, an alkaline substance can be used to adjust the pH value. Preferably, the alkaline substance can be liquid alkali (i.e., sodium hydroxide), lithium hydroxide, potassium hydroxide, baking soda, soda ash, etc.

[0065] In some specific embodiments, the pH of the coupling component solution F in step 5) is 6 - 10, and the preferred pH value is 6.

[0066] In addition, for the reaction conditions in step 5), the present invention does not make any special limitation, as long as the coupling product can be prepared. In some specific embodiments, in step 5), the pH value of the reaction solution is 6.0 - 12.5, and the reaction time is 6 hours.

[0067] Further, the liquid black direct dye is spray-dried to obtain the black direct dye dry powder product of the present invention.

[0068] In a third aspect of the present invention, there is provided a use of the black direct dye according to the first aspect of the present invention or the black direct dye composition according to the second aspect of the present invention for dyeing and / or printing of fibers or their fabrics.

[0069] Specifically, the fibers may be various fiber materials such as cellulose fibers, silk fibers, protein fibers, polyester, cotton, acrylic fibers, etc.

[0070] In addition, the black direct dye of the present invention can also be used as an ink.

[0071] Effect of the Invention

[0072] The black direct dye of the present invention not only has excellent comprehensive dyeing performance, but also has a simple and feasible synthesis method and easy-to-control conditions, filling the market gap of black direct dyes. Detailed implementation mode:

[0073] Hereinafter, the content of the present invention will be described in detail. The description of the technical features recorded below is based on the representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples.

[0074] In addition, in order to better illustrate the present invention, numerous specific details are given in the following detailed implementation mode. Those skilled in the art should understand that the present invention can also be implemented without some specific details. In other instances, methods, means, equipment and steps well known to those skilled in the art are not described in detail in order to highlight the gist of the present invention.

[0075] Examples

[0076] The embodiments of the present invention will be described in detail below in conjunction with the examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. Those not specified in the examples are carried out under conventional conditions or conditions recommended by the manufacturer.

[0077] The reagents or instruments used without indicating the manufacturer can be obtained through commercial purchase or are conventional products prepared conventionally.

[0078] Example 1:

[0079] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline. Stir the slurry for 2 hours, add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice, and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excess nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0080] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour, then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazo product obtained in (1). After adding, keep the system temperature at 5 - 8 °C. At the same time, adjust the pH value of the system to 4 with baking soda. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0081] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide, and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C, then add the sodium sulfide solution, control the system temperature at 20 - 40 °C during the addition. After the addition, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0082] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir and maintain the system temperature at 3 - 5 °C. Keep the temperature for 6 hours to reach the reaction end point.

[0083] (5) Add 100 g of water to a beaker, and then add 47 g of m-aminophenol. Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, then quickly add the m-aminophenol solution. At the same time, maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray-dry the obtained product to obtain the dry powder product of the black direct dye. Denote it as S1, which is a black direct dye composition with the components shown in the following (I-1) and (I-3).

[0084]

[0085] Example 2:

[0086] (1) Add 100 g of water to a beaker, then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then add 84 g of p-nitroaniline. Stir for 2 hours in a slurry, then add 170 g of concentrated hydrochloric acid. Cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, with the temperature at -4 to 5 °C, and the addition time is 5 minutes. After adding, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, add a small amount of p-nitroaniline to eliminate the excess nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0087] (2) Add 1000 g of water to a beaker, then add 115 g of H acid. Stir for half an hour, then adjust the pH value of the system to 5.5 with liquid alkali. After it becomes clear, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazo product obtained in (1). After adding, keep the system temperature at 5 - 8 °C. At the same time, adjust the pH value of the system to 4 with sodium bicarbonate. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0088] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C, then add the sodium sulfide solution, control the system temperature at 20 - 40 °C during the addition. After adding, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0089] (4) Add 100 g of water to a beaker, then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir while maintaining the system temperature at 3 - 5 °C. Keep the temperature for 6 hours to reach the reaction end point.

[0090] (5) Add 100 g of water to a beaker, then add 47 g of m-bis. Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, then quickly add the m-bis solution. At the same time, maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray-dry the obtained product to get the dry powder product of the black direct dye. Denote it as S2, which is the black direct dye of the components shown in the following (I-2).

[0091]

[0092] Example 3:

[0093] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved, and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline, stir the slurry for 2 hours, add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice, and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir and react for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0094] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour, then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazonium product obtained in (1). After adding, keep the system temperature at 5 - 8 °C. At the same time, adjust the pH value of the system to 4 with baking soda, stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0095] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide, and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C, then add the sodium sulfide solution, control the system temperature at 20 - 40 °C during the addition, and keep the system temperature at 35 - 40 °C and react for 2 hours after the addition. After 2 hours, reach the reaction end point to obtain the black base solution.

[0096] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. After adjusting the pH value of the system to 11, add 165 g of hydrochloric acid. Stir and maintain the system temperature at 3 - 5 °C, and keep warm and react for 6 hours to reach the reaction end point.

[0097] (5) Add 100 g of water to a beaker, and then add 47 g of resorcinol. Stir until it is completely dissolved. After adjusting the pH of the reaction product system obtained in (4) to 6.0, quickly add the resorcinol solution, and at the same time maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray-dry the obtained product to obtain the dry powder product of the black direct dye. Denote it as S3, which is a black direct dye containing the components shown in the following (I-4).

[0098]

[0099] Example 4:

[0100] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline. Stir the slurry for 2 hours, add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0101] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour and then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazo product obtained in (1). After adding, keep the system temperature at 5 - 8 °C. At the same time, adjust the pH value of the system to 4 with baking soda. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0102] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C and then add the sodium sulfide solution. Control the system temperature at 20 - 40 °C during the addition. After the addition, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0103] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir and maintain the system temperature at 3 - 5 °C. Keep the temperature for 6 hours to reach the reaction end point.

[0104] (5) Add 100 g of water to a beaker, and then add a mixture of 47 g of m-phenylenediamine and resorcinol (molar ratio 1:1). Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, then quickly add the mixed solution of m-phenylenediamine and resorcinol. At the same time, maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray-dry the obtained product to obtain the black direct dye dry powder product, denoted as S4, which is a black direct dye composition containing components (Ia), (I-4), (I-5) and (I-6).

[0105] Example 5:

[0106] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline, stir for 2 hours while pulping, add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0107] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour and then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazonium product obtained in (1). After adding, keep the system temperature at 5 - 8 °C. At the same time, adjust the pH value of the system to 4 with sodium bicarbonate. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0108] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C and then add the sodium sulfide solution. Control the system temperature at 20 - 40 °C during the addition. After the addition, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0109] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir while maintaining the system temperature at 3 - 5 °C. Keep the temperature for 6 hours to reach the reaction end point.

[0110] (5) Add 100 g of water to a beaker, and then add a mixture of 47 g of m-phenylenediamine and m-aminophenol (molar ratio 1:1). Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, and then quickly add the mixed solution of m-phenylenediamine and m-aminophenol. At the same time, maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray dry the obtained product to obtain the dry powder product of the black direct dye, denoted as S5, which is a black direct dye composition containing components (Ia), (I-1), (I-7), (I-8), (I-9), and (I-10).

[0111] Example 6:

[0112] (1) Add 100 g of water to a beaker, then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline. Stir for 2 hours after pulping, then add 170 g of concentrated hydrochloric acid. Cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0113] (2) Add 1000 g of water to a beaker, then add 115 g of H acid. Stir for half an hour and then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 to 10 °C. Quickly add the H acid solution to the diazonium product obtained in (1). After adding, keep the system temperature at 5 to 8 °C. At the same time, adjust the pH value of the system to 4 with sodium bicarbonate. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0114] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C and then add the sodium sulfide solution. Control the system temperature at 20 to 40 °C during the addition. After the addition, keep the system temperature at 35 to 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0115] (4) Add 100 g of water to a beaker, then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir and maintain the system temperature at 3 to 5 °C. Keep the temperature for 6 hours to reach the reaction end point.

[0116] (5) Add 100 g of water to a beaker, then add 47 g of the mixture of m-bis and m-phenylenediamine (molar ratio 1:1). Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, then quickly add the mixed solution of m-bis and m-phenylenediamine. At the same time, maintain the pH value of the system at 6.0 to 12.5. Stir and react for 6 hours to reach the end point. Spray dry the obtained product to get the dry powder product of the black direct dye, denoted as S6, which is a black direct dye composition containing components (Ia), (I-2), (I-11) and (I-12).

[0117] Example 7:

[0118] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline, and stir for 2 hours after pulping. Then add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice, and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, with the temperature at -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0119] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour, and then adjust the pH value of the system to 5.5 with liquid alkali. After it becomes clear, cool down to 5 to 10 °C. Quickly add the H acid solution to the diazonium product obtained in (1). After the addition, keep the system temperature at 5 to 8 °C. At the same time, adjust the pH value of the system to 4 with sodium bicarbonate, and stir for 8 hours to obtain the coupling product, and let it stand for later use.

[0120] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide, and stir until it is completely dissolved without lumps, and then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C, and then add the sodium sulfide solution. Control the system temperature at 20 to 40 °C during the addition. After the addition, keep the system temperature at 35 to 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0121] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir while maintaining the system temperature at 3 to 5 °C, and keep the temperature for 6 hours to reach the reaction end point.

[0122] (5) Add 100 g of water to a beaker, and then add 47 g of the mixture of m-aminophenol and m-bis (molar ratio 1:1). Stir until it is completely dissolved. After adjusting the pH of the reaction product system obtained in (4) to 6.0, quickly add the mixture solution of m-aminophenol and m-bis. At the same time, maintain the pH value of the system at 6.0 to 12.5. Stir for 6 hours to reach the end point. Spray dry the obtained product to obtain the dry powder product of the black direct dye, denoted as S7, which is a black direct dye composition containing components (I-1), (I-2), (I-3), (I-13), (I-14), (I-15) and (I-16).

[0123] Example 8:

[0124] (1) Add 100 g of water to a beaker, then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline. Stir for 2 hours while pulping, then add 170 g of concentrated hydrochloric acid. Cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, with the temperature at -4 to 5 °C, and the addition time is 5 minutes. After adding, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excess nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0125] (2) Add 1000 g of water to a beaker, then add 115 g of H acid. Stir for half an hour and then adjust the pH value of the system to 5.5 with liquid alkali. After it becomes clear, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazonium product obtained in (1). After adding, keep the system temperature at 5 - 8 °C. At the same time, adjust the pH value of the system to 4 with baking soda. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0126] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C and then add the sodium sulfide solution. Control the system temperature at 20 - 40 °C during the addition. After adding, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0127] (4) Add 100 g of water to a beaker, then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir while maintaining the system temperature at 3 - 5 °C. Keep warm and react for 6 hours to reach the reaction end point.

[0128] (5) Add 100 g of water to a beaker, then add a mixture of 47 g of m-aminophenol and resorcinol (molar ratio 1:1). Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, then quickly add the mixed solution of m-aminophenol and resorcinol. At the same time, maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray dry the obtained product to get the black direct dye dry powder product, denoted as S8, which is a black direct dye containing components (I-1), (I-3), (I-4), (I-17), (I-18), (I-19), (I-20).

[0129] Example 9:

[0130] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline. Stir for 2 hours after pulping, add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours, and at the same time put in a small amount of p-nitroaniline to eliminate the excess nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0131] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour and then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazonium product obtained in (1). After adding, keep the system temperature at 5 - 8 °C, and at the same time adjust the pH value of the system to 4 with baking soda. Stir for 8 hours to obtain the coupling product and let it stand for later use.

[0132] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C and then add the sodium sulfide solution. Control the system temperature at 20 - 40 °C during the addition. After the addition, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0133] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir while maintaining the system temperature at 3 - 5 °C. Keep the temperature for 6 hours to reach the reaction end point.

[0134] (5) Add 100 g of water to a beaker, and then add 47 g of the resorcinol and m-bis mixture (molar ratio 1:1). Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, and then quickly add the resorcinol and m-bis mixed solution. At the same time, maintain the pH value of the system at 6.0 - 12.5. Stir for 6 hours to reach the end point. Spray dry the obtained product to obtain the black direct dye dry powder product, denoted as S9, which is a black direct dye containing components (I-2), (I-4), (I-21), and (I-22).

[0135] Example 10:

[0136] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline, stir for 2 hours after pulping, add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, the temperature is -4 to 5 °C, and the addition time is 5 minutes. After the addition, keep the temperature at -5 to 5 °C and stir for 2 hours, and at the same time put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0137] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour and then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazo product obtained in (1). After adding, keep the system temperature at 5 - 8 °C, and at the same time adjust the pH value of the system to 4 with baking soda. Stir and react for 8 hours to obtain a coupling product, and let it stand for later use.

[0138] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, and let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C and then add the sodium sulfide solution. Control the system temperature at 20 - 40 °C during the addition. After the addition, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain a black base solution.

[0139] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. After adjusting the pH value of the system to 11, add 165 g of hydrochloric acid. Stir and maintain the system temperature at 3 - 5 °C. Keep warm and react for 6 hours to reach the reaction end point.

[0140] (5) Add 100 g of water to a beaker, and then add a mixture of 47 g of resorcinol, m-bis and m-phenylenediamine (molar ratio is 1:1:2). Stir until it is completely dissolved. After adjusting the pH of the reaction product system obtained in (4) to 6.0, quickly add the mixed solution of resorcinol, m-bis and m-phenylenediamine, and at the same time maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray dry the obtained product to obtain a black direct dye dry powder product, denoted as S10, which is a black direct dye composition containing components (Ia), (I-2), (I-4), (I-5), (I-6), (I-11), (I-12), (I-21), (I-22).

[0141] Example 11:

[0142] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then let it stand for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline, and stir for 2 hours while pulping. Then add 170 g of concentrated hydrochloric acid, cool down to 0 °C, add 100 g of crushed ice and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is fast first and then slow, keep the starch potassium iodide test paper blue and the congo red test paper blue, with the temperature at -4 to 5 °C, and the addition time is 5 minutes. After adding, keep the temperature at -5 to 5 °C and stir for 2 hours, and at the same time put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0143] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour, then adjust the pH value of the system to 5.5 with liquid alkali. After it becomes clear, cool down to 5 - 10 °C. Quickly add the H acid solution to the diazo product obtained in (1). After adding, keep the system temperature at 5 - 8 °C, and at the same time adjust the pH value of the system to 4 with baking soda. Stir and react for 8 hours to obtain the coupling product, and let it stand for later use.

[0144] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide and stir until it is completely dissolved without lumps, then let it stand for later use. Adjust the temperature of the product obtained in (2) to 15 °C, then add the sodium sulfide solution, control the system temperature at 20 - 40 °C during the addition, and after adding, keep the system temperature at 35 - 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0145] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid, stir while maintaining the system temperature at 3 - 5 °C, and keep the temperature for 6 hours to reach the reaction end point.

[0146] (5) Add 100 g of water to a beaker, and then add a mixture of 47 g of resorcinol, m-bis, m-aminophenol and m-phenylenediamine (molar ratio 1:1:1:1). Stir until it is completely dissolved. After adjusting the pH of the reaction product system obtained in (4) to 6.0, quickly add the mixed solution of resorcinol, m-bis, m-aminophenol and m-phenylenediamine, and at the same time maintain the pH value of the system at 6.0 - 12.5. Stir and react for 6 hours to reach the end point. Spray-dry the obtained product to obtain the black direct dye dry powder product, denoted as S11, which is a black direct dye composition containing components of formula (Ia) and (I-1)-(I-22).

[0147] Comparative Example 1:

[0148] (1) Add 100 g of water to a beaker, and then add 44 g of sodium nitrite. Stir until it is completely dissolved and then set aside for later use. Add 600 g of bottom water to a three-necked flask, then put in 84 g of p-nitroaniline. Stir for 2 hours while pulping, then add 170 g of concentrated hydrochloric acid. Cool down to 0 °C, add 100 g of crushed ice, and wait for diazotization. Add the dissolved sodium nitrite solution to the three-necked flask at a speed that is first fast and then slow, keeping the starch potassium iodide test paper blue and the congo red test paper blue, with the temperature at -4 to 5 °C and the addition time being 5 minutes. After adding, keep the temperature at -5 to 5 °C and stir for 2 hours. At the same time, put in a small amount of p-nitroaniline to eliminate the excessive nitrous acid. After the reaction, keep the temperature at about 3 °C for later use.

[0149] (2) Add 1000 g of water to a beaker, and then add 115 g of H acid. Stir for half an hour, then adjust the pH value of the system to 5.5 with liquid alkali. After dissolving clearly, cool down to 5 to 10 °C. Quickly add the H acid solution to the diazo product obtained in (1). After adding, keep the system temperature at 5 to 8 °C. At the same time, adjust the pH value of the system to 4 with baking soda. Stir and react for 8 hours to obtain the coupling product, and set it aside for later use.

[0150] (3) Add 300 g of water to a beaker, heat up to 35 °C, add 115 g of sodium sulfide, and stir until it is completely dissolved without lumps, then set aside for later use. Adjust the temperature of the product obtained in (2) to 15 °C, then add the sodium sulfide solution, controlling the system temperature at 20 to 40 °C during the addition. After adding, keep the system temperature at 35 to 40 °C and react for 2 hours. After 2 hours, reach the reaction end point to obtain the black base solution.

[0151] (4) Add 100 g of water to a beaker, and then add 40 g of sodium nitrite. Stir until it is completely dissolved. Add the sodium nitrite solution to the black base solution and stir. Adjust the pH value of the system to 11, then add 165 g of hydrochloric acid. Stir while maintaining the system temperature at 3 to 5 °C. Keep warm and react for 6 hours to reach the reaction end point.

[0152] (5) Add 100 g of water to a beaker, and then add 47 g of m-phenylenediamine. Stir until it is completely dissolved. Adjust the pH of the reaction product system obtained in (4) to 6.0, then quickly add the m-phenylenediamine solution. At the same time, maintain the pH value of the system at 6.0 to 12.5. Stir and react for 6 hours to reach the end point. Spray dry the obtained product to get the dry powder product of the black direct dye, denoted as D1, which is the black direct dye of (I-1).

[0153] Dyeing method

[0154] Take 1 g of each of the black direct dyes obtained in Examples 1-11 and Comparative Example 1, 100 g of cotton fabric and 2-4 g of sodium sulfate, place them in hot water at 40 °C, stir evenly, then heat up to 98-100 °C at a rate of 1-1.5 °C / min, add 8-16 g of sodium sulfate, stir evenly, keep warm for 30-50 min, then gradually cool down to 70 °C, wash thoroughly with water and dry directly to obtain the dyed fabric.

[0155] Performance Test

[0156] Take the dried dyed fabric and determine its rubbing fastness, washing fastness, perspiration fastness, light fastness, color fastness to light and solubility, and calculate its dyeing depth. The methods used refer to GB / T 3920-2008, GB / T3921-2008, GB / T3922-2013, GB / T8426-1998, GB / T8427-1998 and GB / T3671.1-1996 respectively. The performance of the black direct dyes prepared in the examples and comparative examples is shown in Table 1 below:

[0157] Table 1

[0158]

[0159] It can be seen from Table 1 that compared with the comparative example, the solubility, dyeing depth and dyeing performance (especially washing fastness, perspiration fastness, rubbing fastness, light fastness and color fastness to light) of the black direct dye composition of the present invention are all superior to those of Comparative Example 1.

[0160] The above examples of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to enumerate all the embodiments here. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. A black direct dye composition, characterized in that, The black direct dye composition is composed of two or more compounds selected from the black direct dyes (I-1), (I-3), (I-5), (I-6), (I-7), (I-8), (I-9), (I-10), (I-11), (I-12), (I-13), (I-14), (I-15), (I-16), (I-17), (I-18), (I-19), (I-20), (I-21), (I-22) and optionally a compound of formula (Ia); 2. A method for preparing the black direct dye composition according to claim 1, characterized in that, Comprising the following steps: Step 1): Subject a p-nitroaniline solution to a diazotization reaction with a nitrite solution to obtain a diazotized product A; Step 2): Couple the diazotized product A obtained in Step 1) with an H-acid solution to obtain a coupling reaction product B; Step 3): Reduce the coupling reaction product B obtained in Step 2) to obtain a black base solution C; Step 4): Subject the black base solution C to a diazotization reaction with a nitrite solution to obtain a diazotized product D; Step 5): React the diazotized product D from Step 4) with and / or and / or and / or in the coupling component solution F to obtain a black direct dye composition.

3. The method according to claim 2, wherein In Step 1), the nitrite solution is added to the p-nitroaniline solution and the reaction is carried out under acidic conditions.

4. The method according to claim 3, wherein The acid solution used for the acidic conditions is sulfuric acid or hydrochloric acid.

5. The method according to claim 3, wherein When adding, the temperature of the p-nitroaniline solution is maintained at -5 to 5 °C, and the addition time is 5 - 10 minutes.

6. The method according to any one of claims 2-5, characterized in that, In Step 1), the reaction temperature is -5 to 5 °C, and the reaction time is 1.5 - 3 hours.

7. The method according to any one of claims 2-5, characterized in that, In Step 1), the reaction time is 2 hours.

8. The method according to claim 2, wherein In Step 2), the H-acid solution is added to the diazotized product A.

9. The method according to claim 8, wherein When adding, the temperature of the diazotized product A is 5 to 8 °C.

10. The method according to claim 2 or 8, characterized in that In Step 2), the coupling reaction temperature is 5 to 8 °C, the reaction time is 8 - 10 hours, and the reaction pH is 1.5 - 6.

11. The method according to claim 2 or 8, characterized in that In Step 2), the pH of the H-acid solution is 5.5 - 7, and the temperature is 5 - 10 °C.

12. The method according to claim 2, characterized in that, In Step 3), a reducing agent solution is added to the coupling reaction product B for a reduction reaction.

13. The method according to claim 12, wherein The reducing agent in Step 3) is selected from sulfide alkali, polysulfide sodium, ferrous salt, lower oxide, and non-metal hydride.

14. The method according to claim 13, wherein The reducing agent in Step 3) is selected from sodium sulfide, polysulfide sodium, or ferrous salt.

15. The method according to claim 2 or 12, characterized in that, In Step 3), the reaction time is 2 - 5 hours, and the reaction temperature is 35 - 40 °C.

16. The method according to claim 2, characterized in that, In Step 4), the nitrite solution is added dropwise to the black base solution C.

17. The method according to claim 16, characterized in that, The dropping temperature of the nitrite solution is 5 - 10 °C.

18. The method according to claim 2 or 17, wherein When dropping, the pH of the black base solution is maintained at 10 - 11; the reaction time is maintained at 5 - 7 hours, and the reaction temperature is maintained at 3 - 5 °C.

19. The method according to claim 2, wherein Step 5) is to add the coupling component solution F containing and / or and / or and / or to the diazotized product D for reaction.

20. The method according to claim 2 or 19, characterized in that, The pH of the coupling component solution F is 6 - 10.

21. The method according to claim 2 or 19, wherein In Step 5), the pH of the reaction is 6.0 - 12.5, and the reaction time is 6 hours.

22. Use of the black direct dye composition according to claim 1 for dyeing and / or printing of fibers or their fabrics.

23. The use according to claim 22, wherein The fibers are cellulose fibers, protein fibers, polyester, or acrylic fibers.

24. The use according to claim 23, wherein The protein fiber is silk fiber, and the cellulose fiber is cotton.

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