Pigment Red 48:1

• CAS: 7585-41-3
• Catalog Number: ACM7585413
• Category: Main Products
• Molecular Weight: 556.14
• Molecular Formula: C18H11BaClN2O6S
• Synonyms: Barium 4-[(5-chloro-4-methyl-2-sulphonatOphenyl)azO]-3-hydroxy-2-naphthoate
• Appearance: Red to orange powder

Case Study

Pigment Red 48:1 as an Organic Pigment with Ultrasound-Enhanced Properties

Rahmani, Farjad, et al. Results in Chemistry 7 (2024): 101459.

Pigment Red 48:1, an azo-based organic pigment (barium salt), is widely used in printing inks and plastics. Ultrasound irradiation effectively reduces its particle size and improves key application properties such as transparency, hiding power, and lightfastness without altering its chemical resistance.
Experimental Protocol: Aqueous suspensions of Pigment Red 48:1 were irradiated with a 20 kHz ultrasonic probe (56 W, pulse 8) for 3, 6, or 10 min. After filtration and drying, the pigments were incorporated into alkyd resin, drawn onto test panels, and evaluated by spectrophotometry and a grindometer.
Performance Evaluation: The median particle size decreased from 35 µm (blank) to 25 µm after 3 min and 20 µm after 6 min, then remained at 25 µm after 10 min. Transparency (G) changed from 81% (blank) to 79-80% after irradiation, while hiding power (OP) increased from 65% to 68-69%. Light resistance improved significantly: color change (Δ) after 10 days of sunlight exposure was 2.9 for the blank versus 1.2 for the 6 min sonicated sample. Brightness (L), redness (A), yellowness (B), and color tint (H) showed minimal variation. Water, acid, alkali, and heat resistance remained unchanged.
Conclusion: Controlled ultrasound treatment of Pigment Red 48:1 reduces particle size and enhances optical performance and lightfastness, offering an efficient, economical modification method for the pigment industry.