Direct Brown N - High-Quality Direct Dye from Reliable China Suppliers and Factory
Product Characteristics
Physical and Chemical Properties
Solubility
Direct Brown N is easily soluble in cold water / warm water (25°C solubility ≥ 20g/L), and the solution is clear chestnut brown.
It dissolves in ethanol to form a light brown color, is slightly soluble in acetone, and is insoluble in non-polar solvents.
Acid-Base Stability
Direct Brown N has good alkali resistance: stable at pH 7–11, suitable for weakly alkaline / neutral systems (such as papermaking).
It turns red-brown in concentrated sulfuric acid, forms brown precipitate after dilution; there is no obvious color change in concentrated caustic soda.
Affinity
Direct Brown N has strong affinity for cotton, viscose, hemp, and non-woven fabric, with high dyeing rate at 60–80°C.
Color Fastness (Conventional Level)
| Fastness Property | Grade Level | Performance Details |
|---|---|---|
| Sunlight Fastness | Grade 3 | Stable indoors, requires fixation outdoors. |
| Water Wash Fastness | Grade 2–3 | Easily fades during wet washing, can reach Grade 3–4 after fixation. |
| Dry Friction Fastness | Grade 4 | Excellent dry rub resistance. |
| Wet Friction Fastness | Grade 3 | Moderate wet rub resistance. |
| Sweat Fastness | Grade 3 | Standard performance under perspiration exposure. |
Core Advantages
- Natural Color: Pure chestnut brown, warm yellow-brown, retro and high-end, suitable for earth tones.
- Easy to Dissolve: Soluble quickly in both cold and hot water, simple to mix, not prone to caking, suitable for automated batching.
- Stable Against Alkali: pH ≤ 11 does not precipitate, suitable for washing fluids, laundry detergents, water-based color pastes, etc.
- High Cost-Effectiveness: Affordable, has good uniformity, suitable for medium-light to medium-dark color dyeing.
- Removable Dyeing Performance: Removable, suitable for printing and partial fading processes.
Limitations
- Sunlight Resistance: Generally, Direct Brown N has a sunlight fastness of Grade 3, and it is prone to fading in the long term outdoors, not as good as Direct Brown 95 (5–6 grades).
- Water Wash Fastness: Weak; requires fixation treatment to improve wet fastness.
- Sensitive to Hard Water: Calcium and magnesium ions easily cause color bleeding; recommend using soft water or adding chelating agents.
Typical Applications
Industrial Coloring
Textile Printing and Dyeing
Frequently Asked Questions (FAQ)
What type of dye is Direct Brown N?
Direct Brown N is a standard di-azo direct dye characterized by its warm chestnut brown tone, primarily used for cellulose fibers and industrial coloring.
How soluble is Direct Brown N in water?
It features excellent solubility in both warm and cold water, achieving a solubility of 20g/L or higher at 25°C, which results in a clear chestnut brown solution.
What is the color fastness rating for Direct Brown N?
It has a dry friction fastness of Grade 4, wet friction of Grade 3, sweat fastness of Grade 3, and sunlight fastness of Grade 3. For wash-critical applications, using a fixing agent can elevate wash fastness to Grade 3-4.
Can Direct Brown N be used in alkaline environments?
Yes, it has good alkali resistance and remains stable within a pH range of 7 to 11, making it highly suitable for neutral to weakly alkaline systems like papermaking.
What precautions should be taken regarding water quality?
Direct Brown N is sensitive to hard water. High concentrations of calcium and magnesium ions can trigger color bleeding, so using soft water or adding chelating agents is highly recommended.