High Quality Direct Dye Direct Blue 71

1.Solubility

Direct Blue 71 has moderate water solubility. The aqueous solution appears as a bright blue color; it is slightly soluble in cellulose and extremely slightly soluble in ethanol. It does not dissolve in other organic solvents.

Solubility: 60°C approximately 10g/L, 97°C approximately 20g/L

Direct Blue 71's alkali resistance stability: stable at pH 7-10; highly alkaline (pH > 11) causes precipitation easily (the car wash solution should control pH ≤ 10)

2.Acid-base reaction characteristics

Aqueous solution + concentrated hydrochloric acid: blue precipitate

Aqueous solution + concentrated alkali: red-purple precipitate

Concentrated sulfuric acid: blue to gray-black, diluted to red-purple precipitate

3.Dyeing characteristics

Color: deep red blue, rich and stable

Affinity: Direct Fast Blue B2RL has good affinity for cellulose fibers such as cotton, viscose, and linen

Dyeing rate: medium to high; Direct Fast Blue B2RL's uniformity and removability are average

Sunlight fastness: 5-6 grades

Water washing fastness: 3-4 grades

Dry rubbing fastness: 4 grades

Wet rubbing fastness: 2-3 grades

1.The unique direct blue 71 color light: deep blue red, more intense than ordinary direct blue, suitable for dark coloring.

2.Direct blue 71 has better sun resistance: 5-6 sun exposure levels, superior to some direct blue, does not fade easily when used outdoors.

3.Direct Fast Blue B2RL has high cost-effectiveness: moderate price, widely applicable. Limitations

4.Direct Fast Blue B2RL, Alkali Resistant General: pH > 11. It tends to precipitate and is not suitable for strong alkaline car washing solutions (pH 11–12).

5.Direct Blue 71 is sensitive to iron ions: The color becomes darker when encountering iron ions during dyeing. It is recommended to dissolve in soft water.

Five. Application Scope

1.Industrial Coloring

Neutral / Weakly Alkaline Car Wash Solution, Glass Water: Suitable for deep blue coloring. Caution should be exercised with strong alkaline systems.

Direct Blue 71 can be used in water-based cleaners, laundry detergents, paper, leather, soap, bamboo and wood fiber coloring.

2.Textile Printing and Dyeing

Direct Fast Blue B2RL presents red light deep blue coloring in cotton, viscose, hemp, non-woven fabric, home textiles, knitted products, etc.

Silk, nylon and blended fabrics of viscose / nylon are also suitable for dyeing.

Six. Usage Process of Direct Blue 71

1.Mixing Solution: Stir and dissolve in 50–60℃ warm water. Avoid lumps and do not use strong alkaline water.

2.Dosage: 0.2–0.5g/kg (0.002–0.005% by weight), 3% by weight is sufficient for deep blue color.

3.pH Control: Strictly control pH 8–10. Beyond this range, it tends to precipitate.

4.Compatibility: Direct Fast Blue B2RL has good compatibility with non-ionic / anionic surfactants and does not affect foaming.