Acid Red 299 is a water-soluble acid dye that produces vivid red to purplish-red shades and is primarily used for dyeing and direct printing on protein and polyamide fibres such as wool, silk and nylon; it is also applied in leather dyeing and selective ink/paint formulations.
TRADE NAME:Weak Acid Dark Red N-5BL,Rubine N-5BL,Weak Acid Red N-5BL,Weak Acid Rubine A5BL,Acid Rubine N-5BL,Acid Red N-5BL
Soluble in water. Water solution is red, to produce brown precipitation rare hydrochloric acid, sodium hydroxide to join after yellow. The strong sulfuric acid for olive green, blue become diluted.
The appearance is jujube red powder. It is soluble in water and has a solubility in water of 50g/L (90°C). The aqueous solution is red, adding dilute hydrochloric acid to produce a brown precipitate; after adding sodium hydroxide, it is yellow. In concentrated sulfuric acid, it is olive green. It turns blue after dilution.
Standard | Fiber | Soaping | Persperation Fastness | Oxygen bleaching | Light | |
Fading | Stain | |||||
AATCC | Wool | 5 | 5 | 5 | 4 | |
ISO | Wool | 5 | 4 | 5 | 5-6 | |
Test Methods | fiber | seawater | soaping | Perspiration | Sun exposure | ||
discolor | Staining | discolor | Staining | ||||
AATCC | wool | 5 | 5 | 5 | 5 | 5 | 4 |
soaping ISO105-C06-B2S (50℃ | flooding ) ISO105-E01 | Alkali perspiration ISO105-E04 | Sun exposure ISO105-B02 | friction ISO105-X12 | ||||||||
discolor | Nylon stain | Cotton stain | discolor | Nylon stain | Cotton stain | discolor | Nylon stain | Cotton stain |
0.5% (owf) |
2.0% (owf) | dry | wet |
3~4 | 5 | 4 | 4~5 | 5 | 5 | 4 | 5 | 5 | 6 | 6 | 5 | 5 |
Acid Red 299 is optimized for protein and polyamide fibers—wool, silk and nylon—where it produces bright, even rubine-red to purplish-red shades. On protein fibers you’ll usually see slightly richer depth and better wet-fastness compared with some synthetic substrates. For blended goods, pretesting is recommended to confirm levelness and shade.
Supplier technical sheets commonly report moderate-to-good fastness: typical values are around 3–4 (scale 1–5) for water and perspiration fastness and 4 for rubbing fastness under optimized recipes. Actual performance depends strongly on the substrate, salt/acidity control, and after-treatment (soaping, fixation).
Yes — Acid Red 299 is sometimes formulated into specialty inks and coatings where a water-soluble acid dye is acceptable. Because it is a soluble dye (not a pigment), it will impart transparent, vivid color and may require resin/plasticizer systems and stabilizers for durability in coatings. Consult supplier technical literature for recommended binder systems and light/solvent stability data.
To deepen shade without losing brightness, combine Acid Red 299 with a compatible blue or violet acid dye (lab-scale trials first). For more purple tones, blend small percentages of an acid violet; for deeper maroons add a brownizing modifier or small amount of a yellow-blocking dye. Always record recipe and test on the exact fabric and process—dye interactions and substrate affinities vary.
Acid Red 299 is a fine powder—avoid inhalation of dust and contact with eyes or prolonged skin exposure. Follow the product SDS: use dust-mask/respirator, safety glasses, and gloves; store in a cool, dry, ventilated place. Ingestion may cause gastrointestinal upset; treat spills as non-combustible but avoid creating dust clouds.
