Vat Blue RSN

Product name: Vat Blue 4

C.I.: Vat Blue 4

C.I.: 69800

Alias: Vat Blue RD; Vat Blue RS; Vat Blue RSN; Shilin Blue RS; Shilin Blue RSN; Indanthrene Blue RSN; Indanthrone; Anthraquinone Blue; Vat Brilliant Blue 5RL

Molecular structural formula:

Molecular formula: C28H14N2O4

Molecular weight: 442.42

CAS number: 81-77-6

EINECS: 201-375-5

Risk terms: R20 / R21 / R22

Security term: S22 / S36/37/39;

Appearance: blue black powder

Hue: Brilliant red light blue

Physical properties:

Insoluble in water, acetic acid, ethanol, pyridine, xylene, toluene, slightly soluble in chloroform (hot), o-chlorophenol, quinoline. It is brown in concentrated sulfuric acid and produces blue precipitation after dilution. It is blue in alkaline solution of Sodium hydroxide and reddish blue in acidic solution.

Melting point: 470~500℃.

Color index: 69800.

Water solubility: <0.1g/100mL (21℃).

Chemical properties:

Alkaline reduction leuco body is blue; acid reduction leuco body is red light blue. Prone to excessive oxidation and reduction, sensitive to hard water, and not resistant to chlorine bleaching.

use:

Vat Blue RSN is mainly used for cotton fiber dyeing and cotton cloth printing. It is also used for two-bath over-dyeing of V-cotton and polyester-cotton fabrics. Dyed viscose fiber has a lighter color. It can be used for dyeing cotton fiber, it can also be used for direct printing of cotton cloth, and it can also be processed into pigments. Can be combined with vat blue, brown, olive, etc. to fight blue, dark gray, etc. It is also used to make pigments for inks. It can replace phthalocyanine blue and permanent violet RL to prepare red light blue paint.

production method:

Method 1: Melting method

Using 2-aminoanthraquinone as a raw material, after alkali fusion with a warm alkali, the product is refined with a sodium hydroxide solution. Or use 2-aminoanthraquinone as raw material, dimethyl sulfoxide as solvent, and alkali fusion reaction with potassium hydroxide, and then refined by sodium hydroxide solution to obtain the product. Add 595kg of anhydrous mixed alkali (68% potassium hydroxide) into the condensation pot. After heating and melting, add 131kg sodium acetate (98%) and 1.5kg oleic acid (industrial product). Close the condensation pot, heat it to 185 -190℃, and at the same time use nitrogen to expel the air, keep the reaction liquid under nitrogen protection, add 263kg 2-aminoanthraquinone within 30min, control the temperature not to exceed 215℃, keep the temperature for 1h after the addition, and then add 25kg sodium nitrite (98%), control the temperature not to exceed 230℃, add it in about 2h. Continue to stir for 20 minutes to complete the alkali fusion reaction. Put 5000L of water in the refining pot, blow in nitrogen to drive the air, put in the alkali-melted materials, and stir for 2h; reduce the temperature to about 51℃, add 110kg of sodium hydroxide, stir slowly, and when the temperature is lowered to 45℃, crystals will precipitate. Filter and wash the filter cake with aqueous solution of sodium sulfonate (the washing water is made up of 20L liquid caustic soda, 20kg sodium hydroxide, and 5000L water), and then wash with warm water at 45℃ until the filtrate is bluish, drain it to obtain the wet material of dye leuco body . Add the wet dye leuco material into the beating machine, beating with an appropriate amount of water, and oxidizing at 60°C for 6 hours in air, adding 150kg of diffusing agent NNO for sanding, and spray drying to obtain the finished product. Each batch is about 138kg (100%).

Method 2: Solvent method

Add 15L dimethyl sulfoxide and 6.802kg 2-aminoanthraquinone to the condensation kettle, and raise the temperature to 132℃ in about 1h. After the 2-aminoanthraquinone is basically dissolved, continue to heat up to 130-150℃ for 30min to make it completely dissolved . At this time, the heating was stopped and air was introduced. The temperature dropped to about 128°C, and 4.4L potassium hydroxide solution (39.8%) was added within 10 minutes. And continue to pass in air, keep the reaction at (125±2)℃ for 4h. Then add 20L of water, filter the material temperature down to about 80℃, wash the condensation pot with 40L of water at 50-60℃, wash the filter cake with it, and drain it. Add 380L of water to the refining pot, beat the filter cake for 1h, add 27kg of alkali (43% sodium hydroxide), heat up to 56-57℃, add 5.44kg of sodium hydroxide (85%), keep the temperature for 20min, and then within 40min Cool down to 52℃, crystallize out, filter, filter cake is washed with water around 50℃ [prepared with 410L water, 5.8kg sodium hydroxide (43%), 0.82kg sodium hydroxide (85%)], then washed with water and drained . Add 100L of water to the acidification pot, add the refined filter cake, beat for 2h, add water to adjust the volume to 200L, add sulfuric acid to adjust the pH to 2-3 (approximately use 12.34% sulfuric acid 10kg). Stir for 20min, filter, wash with water until neutral, and blow dry. The finished product is obtained by sanding.

Other description:

One of the earliest anthraquinone vat dyes. According to the dye nomenclature, Vat Blue RSN is expressed as a reddish, vat blue dye with standard intensity, and named C.I. Vat Blue 4 according to the "Dye Index". It was first produced by German chemist R. Born in 1901, and it is still the most important vat dye variety with the largest output.

Industrially, 2-aminoanthraquinone is used as raw material, and it is prepared by potassium hydroxide-sodium hydroxide mixed alkali fusion condensation. Then, it is reduced to leuco crystals through the sodium hydroxide solution, and the dissolved impurities are filtered out under the protection of nitrogen. After washing, it is acidified with sulfuric acid and oxidized in air to be refined. The obtained dye crystal filter cake is diluted and beaten, added with dispersant and other auxiliary agents, ground in a sand milling equipment to control the fineness and strength of the dye, and then spray-dried into a commercial product of Vat Blue RSN.

Vat Blue RSN is bright in color, and has excellent fastness to light, alkali, washing and perspiration, but it is not resistant to chlorine bleaching. It is mainly used for dyeing cotton fiber, viscose fiber, vinylon, etc., and can also be used as an organic pigment.

Specification: GB/T 1867—1997

The appearance is dark blue uniform powder.

The shade is similar to the standard product.

The intensity is (100±3) points of the standard f product.

The dye fastness on cotton fabric meets the standard grade.

Diffusion ≥3 grade.

Fineness (residue content through 250μm sieve) ≤ 2%.

Fastness performance