Appearance of Direct Red 23(Direct Red 4BS) is generally purple-red uniform powder. Dissolved in water is bright red, slightly soluble in alcohol, orange, insoluble in acetone. Large red to magenta in concentrated sulfuric acid After dilution, it turns brownish orange; there is orange-yellow precipitate in concentrated nitric acid; it is red in concentrated sodium hydroxide, and dilute sulfuric acid is added to the blue water in the aqueous solution. Concentrated hydrochloric acid has burgundy precipitate, plus 10% soda ash. Change. When the copper ion color is dimmed, the color of the iron ion is almost unchanged.
TRADE NAME:Direct Red 4BS,Fast Red 4BS,Direct Scarlet 4BS,Direct Scarlet Lightfast,Direct Scarlet SE,Direct acid resistant red 4BS,Enianil Fast Scarlet 4BS,Erie Fast Scarlet SCB,Nippon Fast Scarlet 4BS,Nyanza Fast Scarlet 4BSA,Orbamin Scarlet 4BS,Paper Scarlet 4BS
| Dyeing depth % | 2 |
| Insolubles % | 0.15 |
| Light Fastness | 2-3 |
| Washing Fatness | 3 |
| Rubbing fastness(dry) | 3 |
| Rubbing fastness(wet) | 2 |
sun exposure | soaping | flooding | perspiration | rubbing | ironing | acidand alkali resistant | |||||||
standard depth | 1/12 depth | original color change | white fiber stained | original color change | white fiber stained | original color change | white fiber stained | dry | wet | sulfuric | acetate | sodaash | |
— | — | 3~4 | 1~2 | 4 | 3 | 3~4 | 4 | 4 | 2~3 | 4~5 | 2~3 | 1 | 4 |
Direct Red 23 Mainly used in viscose etc of cellulose fiber dyeing, also can be used for silk, wool, paper and pulp dyeing, also can be used in the manufacture color which have pigment.
1.Direct Red 23 (Direct Red 4BS) dyed cotton or viscose fiber has yellow-red color, good dyeing rate, poor transferability, sensitive to salt. It is recommended to slowly heat up and add salt to control the dyeing, which can obtain uniform color. The dye bath should be naturally cooled to 80 ° C in the later stage to facilitate the dye exhaustion.
2.It can be used to dye silk and wool. The dyed silk fabric is lighter than the upper dyed cotton and viscose fiber yellow, and can be dyed with Jiaming powder and acetic acid. Cotton, viscose and other When the fiber is dyed in the same bath, the wool is much lighter than the cotton and viscose fiber, the nylon is heavily stained, and the diacetate and polyester are slightly stained.
3. It can be used for direct printing of cotton or viscose fabric, plus urea and disodium hydrogen phosphate to adjust the color paste.
Can also be used for silk fabric printing.
4. It is also used for color matching with yellow, orange, red and brown dyes. It is used for dyeing cotton or viscose fiber.
When the dark color is dyed slowly, it is easy to control, the light color is dyed very fast, and due to the poor transferability,Direct Red 23 is easy to produce color flowers, which should be noted.
It dyes cellulosic fibers (cotton, rayon) efficiently by direct adsorption; performance on synthetics is limited without special carriers or mordants.
After-treatment (salts, fixation agents, or appropriate leveling agents) and proper rinsing improve wet and light fastness; testing on the target fabric is recommended.
It is an azo dye with environmental persistence and reported toxic concerns in some studies—use gloves, eye protection, and follow SDS/waste disposal rules.
Store dry in a cool, ventilated area away from strong oxidizers; shelf life depends on grade/purity but typically 1–3 years under proper conditions.
Use levels vary by shade depth and substrate (typically measured as % owf — 0.1–3% for lighter shades; higher for deep shades). Always run lab trials.
