A preparation method of a bluish purple organic pigment

Abstract

The present invention belongs to the technical field of organic pigments, and particularly relates to a preparation method of a blue-violet organic pigment, which includes: adding water and soda ash into a coupling pot and stirring evenly, adding 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid during stirring and stirring for 0.5-1 h, then adding 4-chlorobenzoyl chloride and controlling the pH, cooling to 5-10 °C to obtain a coupling solution; adding water and 1-naphthylamine into a reaction pot, adding hydrochloric acid and stirring for 1-2 h, then adding a sodium nitrite solution in a low-temperature environment for a constant-temperature diazotization reaction for 2-3 h to obtain a diazo solution; adding the diazo solution into the coupling solution, adjusting the pH and reacting for 2 h, then adding an aqueous barium chloride solution and an auxiliary agent, heating to 95 °C, keeping warm for 2 h, finally filtering and rinsing to neutral, and drying and pulverizing to obtain the blue-violet organic pigment. The present invention uses 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid as a coupling component raw material and 1-naphthylamine as a diazotization raw material, and obtains the blue-violet organic pigment through a diazo coupling reaction, enriching the chromatogram of azo organic pigment varieties.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic pigments, and particularly relates to a preparation method of a blue-violet organic pigment. Background Art

[0002] Organic pigments are insoluble organic substances, usually added to the substrate in a highly dispersed state to color the substrate. The fundamental difference between them and dyes is that dyes can dissolve in the used dyeing medium, while pigments are neither soluble in the medium in which they are used nor in the substrate to be colored. Organic pigments have bright colors and strong coloring power; they are non-toxic, but the lightfastness, heat resistance, solvent resistance, and migration resistance of some varieties are often inferior to those of inorganic pigments. Currently, the organic pigments are mainly yellow organic pigments and red organic pigments, but there are few varieties of azo purple organic pigments. Summary of the Invention

[0003] Aiming at the problems in the prior art, the present invention provides a preparation method of a blue-violet organic pigment, which solves the scarcity of existing azo purple organic pigments. Using 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid as the coupling component raw material and 1-naphthylamine as the diazotization raw material, a blue-violet organic pigment is obtained through a diazo-coupling reaction, enriching the chromatogram of azo organic pigment varieties.

[0004] To achieve the above technical objectives, the technical solution of the present invention is as follows:

[0005] A preparation method of a blue-violet organic pigment, comprising the following steps:

[0006] Step 1, preparation of the coupling solution: Add water and soda ash into the coupling pot and stir evenly. During the stirring process, add 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid and stir for 0.5 - 1 h, then add 4-chlorobenzoyl chloride and control the pH, and cool down to 5 - 10 °C to obtain the coupling solution; the structural formula of the coupling component in the azo solution is:

[0007]

[0008] The mass concentration of the soda ash in water is 70 - 90 g / L, the stirring speed is 500 - 1000 r / min, the molar ratio of 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid, 4-chlorobenzoyl chloride, and soda ash is 1:1:4 - 5, the pH is adjusted with soda ash, and the pH is controlled at 8 - 9;

[0009] Step 2, Preparation of diazo solution: Add water and ground 1-naphthylamine into the reaction kettle, add hydrochloric acid and stir for 1-2 h, then add sodium nitrite solution under low temperature environment for constant temperature diazo reaction for 2-3 h to obtain diazo solution. The mass ratio of water to 1-naphthylamine is 10-12:1, the molar ratio of 1-naphthylamine to hydrogen chloride in hydrochloric acid is 1:3-5, the hydrochloric acid used is hydrochloric acid with a mass fraction of 30%, the stirring speed is 200-500 r / min, and the temperature is 0-5 °C; the mass concentration of sodium nitrite in the sodium nitrite solution is 30%, and the molar ratio of sodium nitrite to 1-naphthylamine is 1-1.2:1, and the temperature of the constant temperature diazo reaction is 0-5 °C;

[0010] Step 3, Preparation of organic pigment: Add the diazo solution into the coupling solution, adjust the pH and react for 1-2 h, then add barium chloride aqueous solution and additives, heat up to 95 °C, keep warm for 1-2 h, and finally filter and rinse to neutral, and obtain blue-violet organic pigment after drying and pulverizing; the diazo solution is added into the coupling solution within 1-2 h, the pH is adjusted with soda ash, and the adjusted pH is 8-9, and the reaction temperature is not higher than 30 °C; the coupling combination in the reaction is slightly in excess; the mass concentration of the barium chloride aqueous solution is 20-30%, and the molar ratio of barium chloride to the coupling component is 1-2:1. The additive is one of tallow oil, emulsifier A-105, rosin, hydrogenated rosin, and polymer dispersant, and the mass ratio of the additive to the coupling component is 1-5:100;

[0011] The molecular structural formula of the blue-violet organic pigment is:

[0012]

[0013] The reaction equation is as follows:

[0014]

[0015] From the above description, it can be seen that the present invention has the following advantages:

[0016] 1. The present invention solves the shortage of existing azo purple organic pigments. Using 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid as the coupling component raw material and 1-naphthylamine as the diazotization raw material, a blue-violet organic pigment is obtained through diazo coupling reaction, enriching the chromatogram of azo organic pigment varieties.

[0017] 2. The present invention uses 1-naphthylamine and 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid as raw materials, increases and changes the length of the molecular conjugate system, and converts the dye color into blue-violet.

[0018] 3. The present invention adds chloride ions in the structure, effectively increases the molecular weight, and improves the fastness. Detailed implementation mode

[0019] The present invention will be described in detail in conjunction with embodiments, but no limitations will be made to the claims of the present invention.

[0020] Embodiment 1

[0021] A preparation method of a blue-violet organic pigment comprises the following steps:

[0022] Step 1, preparation of the coupling solution: Add water and soda ash into the coupling pot and stir evenly. During stirring, add 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid and stir for 0.5 h, then add 4-chlorobenzoyl chloride and control the pH, and cool down to 5 °C to obtain the coupling solution; the structural formula of the coupling component in the azo solution is:

[0023]

[0024] The mass concentration of the soda ash in water is 70 g / L, the stirring speed is 500 r / min, the molar ratio of 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid, 4-chlorobenzoyl chloride and soda ash is 1:1:4, the pH is adjusted with soda ash, and the pH is controlled at 8;

[0025] Step 2, preparation of the diazo solution; Add water and ground 1-naphthylamine into the reaction pot, add hydrochloric acid and stir for 1 h, then add sodium nitrite solution in a low-temperature environment for a constant-temperature diazotization reaction for 2 h to obtain the diazo solution. The mass ratio of water to 1-naphthylamine is 10:1, the molar ratio of 1-naphthylamine to hydrogen chloride in hydrochloric acid is 1:3, the hydrochloric acid used is hydrochloric acid with a mass fraction of 30%, the stirring speed is 200 r / min, and the temperature is 0 °C; the mass concentration of sodium nitrite in the sodium nitrite solution is 30%, and the molar ratio of sodium nitrite to 1-naphthylamine is 1:1, and the temperature of the constant-temperature diazotization reaction is 0 °C;

[0026] Step 3, preparation of the organic pigment: Add the diazo solution into the coupling solution, adjust the pH and react for 1 h, then add an aqueous barium chloride solution and an auxiliary agent, heat up to 95 °C, keep warm for 1 h, and finally filter and rinse to neutral, and obtain the blue-violet organic pigment after drying and pulverizing; the diazo solution is added into the coupling solution within 1 h, the pH is adjusted with soda ash, and the adjusted pH is 8, and the reaction temperature is 30 °C; the coupling combination in the reaction is slightly in excess; the mass concentration of the aqueous barium chloride solution is 20%, and the molar ratio of barium chloride to the coupling component is 1:1. The auxiliary agent used is Turkey red oil, and the mass ratio of the auxiliary agent to the coupling component is 1:100;

[0027] The molecular structural formula of the blue-violet organic pigment is:

[0028]

[0029] The reaction equation is as follows:

[0030]

[0031] The blue-violet organic pigment prepared in this example was weighed, and its UV and HPLC were measured and the yield was calculated. The results showed that the dye purity was 85% and the yield was 89%.

[0032] Example 2

[0033] A method for preparing a blue-violet organic pigment, comprising the following steps:

[0034] Step 1, preparation of the coupling solution: Add water and soda ash into the coupling pot and stir evenly. During the stirring process, add 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid and stir for 1 h, then add 4-chlorobenzoyl chloride and control the pH, and cool down to 10 °C to obtain the coupling solution; the structural formula of the coupling component in the azo solution is:

[0035]

[0036] The mass concentration of the soda ash in water is 90 g / L, the stirring speed is 1000 r / min, the molar ratio of 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid, 4-chlorobenzoyl chloride and soda ash is 1:1:5, the pH is adjusted with soda ash, and the pH is controlled at 9;

[0037] Step 2, preparation of the diazo solution; Add water and ground 1-naphthylamine into the reaction pot, add hydrochloric acid and stir for 2 h, then add sodium nitrite solution in a low-temperature environment for a constant-temperature diazotization reaction for 3 h to obtain the diazo solution. The mass ratio of water to 1-naphthylamine is 12:1, the molar ratio of 1-naphthylamine to hydrogen chloride in hydrochloric acid is 1:5, the hydrochloric acid used is hydrochloric acid with a mass fraction of 30%, the stirring speed is 500 r / min, and the temperature is 5 °C; the mass concentration of sodium nitrite in the sodium nitrite solution is 30%, and the molar ratio of sodium nitrite to 1-naphthylamine is 1.2:1, and the temperature of the constant-temperature diazotization reaction is 5 °C;

[0038] Step 3, preparation of the organic pigment: Add the diazo solution into the coupling solution, adjust the pH and react for 2 h, then add an aqueous barium chloride solution and an auxiliary agent, heat up to 95 °C, keep warm for 2 h, and finally filter and rinse to neutral, and obtain the blue-violet organic pigment after drying and pulverizing; the diazo solution is added into the coupling solution within 2 h, the pH is adjusted with soda ash, and the adjusted pH is 9, and the reaction temperature is 20 °C; the coupling combination in the reaction is slightly in excess; the mass concentration of the aqueous barium chloride solution is 30%, and the molar ratio of barium chloride to the coupling component is 2:1. The auxiliary agent uses emulsifier rosin, and the mass ratio of the auxiliary agent to the coupling component is 1:20;

[0039] The molecular structural formula of the blue-violet organic pigment is as follows:

[0040]

[0041] The reaction equation is as follows:

[0042]

[0043] The blue-violet organic pigment prepared in this example was weighed, and its UV and HPLC were measured and the yield was calculated. The results showed that the dye purity was 87% and the yield was 92%.

[0044] Example 3

[0045] A preparation method of a blue-violet organic pigment includes the following steps:

[0046] Step 1, preparation of the coupling solution: Add water and soda ash into the coupling pot and stir evenly. During stirring, add 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid and stir for 1 h, then add 4-chlorobenzoyl chloride and control the pH, and cool down to 8 °C to obtain the coupling solution; the structural formula of the coupling component in the azo solution is:

[0047]

[0048] The mass concentration of the soda ash in water is 80 g / L, the stirring speed is 800 r / min, the molar ratio of 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid, 4-chlorobenzoyl chloride and soda ash is 1:1:5, the pH is adjusted with soda ash, and the pH is controlled at 8;

[0049] Step 2, preparation of the diazo solution; Add water and ground 1-naphthylamine into the reaction pot, add hydrochloric acid and stir for 2 h, then add sodium nitrite solution under low-temperature environment for a constant-temperature diazotization reaction for 2 h to obtain the diazo solution. The mass ratio of water to 1-naphthylamine is 11:1, the molar ratio of 1-naphthylamine to hydrogen chloride in hydrochloric acid is 1:4, the hydrochloric acid used is hydrochloric acid with a mass fraction of 30%, the stirring speed is 400 r / min, and the temperature is 3 °C; the mass concentration of sodium nitrite in the sodium nitrite solution is 30%, and the molar ratio of sodium nitrite to 1-naphthylamine is 1.1:1, and the temperature of the constant-temperature diazotization reaction is 3 °C;

[0050] Step 3, Preparation of the organic pigment: Add the diazo solution to the coupling solution, adjust the pH and react for 2 h, then add an aqueous barium chloride solution and an auxiliary agent, raise the temperature to 95 °C, keep warm for 2 h, finally filter and rinse to neutral, and dry and pulverize to obtain the blue-violet organic pigment; the diazo solution is added to the coupling solution within 1 h, the pH is adjusted with soda ash, and the adjusted pH is 8, and the reaction temperature is 25 °C; the coupling combination in the reaction is slightly in excess; the mass concentration of the aqueous barium chloride solution is 25%, and the molar ratio of barium chloride to the coupling component is 2:1. The auxiliary agent is hydrogenated rosin, and the mass ratio of the auxiliary agent to the coupling component is 3:100;

[0051] The molecular structural formula of the blue-violet organic pigment is as follows:

[0052]

[0053] The reaction equation is as follows:

[0054]

[0055] The prepared blue-violet organic pigment in this example was weighed, UV and HPLC were measured, and the yield was calculated. The results showed that the dye purity was 90% and the yield was 93%.

[0056] Dye performance test

[0057] Example 1 Example 2 Example 3 Sun exposure level 6 7 7 Acid fastness 5 5 5 Migration resistance 5 5 5 Heat resistance 4 5 5 Solvent resistance 4 5 5

[0058] It can be understood that the above specific description of the present invention is only for explaining the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced to achieve the same technical effects; as long as the use requirements are met, they are all within the protection scope of the present invention.

Claims

1. A method for preparing a blue-violet organic pigment, characterized in that: It includes the following steps: Step 1, preparation of the coupling solution: Add water and soda ash into the coupling pot and stir evenly. During stirring, add 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid and stir for 0.5 - 1 h. Then add 4-chlorobenzoyl chloride and control the pH. Cool down to 5 - 10 °C to obtain the coupling solution; Step 2, preparation of the diazo solution: Add water and 1-naphthylamine into the reaction pot, add hydrochloric acid and stir for 1 - 2 h. Then add sodium nitrite solution under low-temperature environment and carry out a constant-temperature diazotization reaction for 2 - 3 h to obtain the diazo solution; Step 3, preparation of the organic pigment: Add the diazo solution into the coupling solution, adjust the pH and react for 1 - 2 h. Then add barium chloride aqueous solution and additives, heat up to 95 °C, keep warm for 1 - 2 h. Finally, filter and rinse until neutral, and after drying and pulverizing, obtain the blue-violet organic pigment.

2. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The mass concentration of the soda ash in water in Step 1 is 70 - 90 g / L, and the stirring speed is 500 - 1000 r / min.

3. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The molar ratio of 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid, 4-chlorobenzoyl chloride and soda ash in Step 1 is 1:1:4 - 5, and the pH is adjusted with soda ash.

4. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The mass ratio of water to 1-naphthylamine in Step 2 is 10 - 12:1, the molar ratio of 1-naphthylamine to hydrogen chloride in hydrochloric acid is 1:3 - 5, the hydrochloric acid used is hydrochloric acid with a mass fraction of 30%, the stirring speed is 200 - 500 r / min, and the temperature is -10 °C.

5. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The mass concentration of sodium nitrite in the sodium nitrite solution in Step 2 is 30%, and the molar ratio of sodium nitrite to 1-naphthylamine is 1 - 1.2:

1. The temperature of the constant-temperature diazotization reaction is 0 - 5 °C.

6. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The diazo solution in Step 3 is added into the coupling solution within 1 - 2 h.

7. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The pH in Step 3 is adjusted with soda ash, and the adjusted pH is 8 - 9.

8. The preparation method of the orchid purple organic pigment according to claim 1, characterized in that: The reaction temperature in Step 3 is not higher than 30 °C.

9. The preparation method of the orchid purple organic pigment according to claim 1, wherein: The mass concentration of the barium chloride aqueous solution in Step 3 is 20 - 30%, and the molar ratio of barium chloride to the coupling component is 1 - 2:

1.

10. The preparation method of the orchid purple organic pigment according to claim 1, wherein: The additive in Step 3 is one of tallow oil, emulsifier A-105, rosin, hydrogenated rosin, and polymer dispersant. The mass ratio of the additive to the coupling component is 1 - 5:100.

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