Pigment Red 21 is a monoazo-based organic pigment widely recognized for its vivid red hue with a yellow tint. It was first developed as a cost-effective alternative to high-performance pigments and is commonly designated as "3132 Dahongfen" in Chinese industrial contexts. This pigment is prized for its bright color and versatility across coatings and inks, but requires careful handling in specific applications due to potential migration issues.
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Basic Properties
- Chemical Composition: Molecular formula C23H16ClN3O2, molecular weight 401.845 g/mol.
- Appearance: A fine, bright red powder with a yellowish undertone, offering high color strength and opacity.
- Physical Traits: Density ranges from 1.45 to 1.60 g/cm³, oil absorption is 30-45 g/100g. Insoluble in water, oil, ethanol, and paraffin, ensuring stability in diverse formulations.
- Core Advantages: Excellent dispersibility in water-based systems, facilitating easy processing and storage with low viscosity.
Key Performance Characteristics
- Light Fastness: Grade 6-7 (on the ISO scale, excellent resistance to fading under sunlight).
- Heat Resistance: Stable up to 130-160°C, suitable for most industrial processes without degradation.
- Chemical Resistance: Acid and alkali resistance at grade 5 (strong), but water and oil resistance at grade 4 (moderate), limiting use in high-exposure environments.
- Limitations: Prone to migration in plastic substrates (e.g., PVC or rubber), making it less ideal for applications requiring high migration resistance; storage should be in cool, dry conditions away from light to maintain stability for ~1 year.
Certifications
Exhibition
Company Profile
Ruicai company was founded in 2009 with the main objective to carry on the business of manufacturers in color pigments and color masterbatch. After years of effort, the company has today become the largest manufacturer of color pigments and color masterbatches in the north of China. Due to the excellent technical team and good after-sales service, the products of the company have been exported to more than 50 countries and have been widely recognized and praised by many overseas customers. The company has established its own brand in the export market and has become a leading exporter of pigments and masterbatches. Ruicai's corporate policy can be summed up as customer satisfaction, reliability, innovation, quality, and service. Customer needs are the center of all activity at Ruicai. The key is that we can provide customized services, and achieving customer satisfaction and recognition is our ultimate goal.
Packaging & Shipping
Packing: Outer paper bag packing, inner plastic bag.
25kg pigments/bag
Lead time: Within 7 workdays after receiving customers' payment.
After Sales Service
1. According to the requirements of customers, we choose the safest and most cost-effective mode of transportation for customers
2. Tracking goods until the goods are safely delivered to customers
3. 24 hours online, we will provide technical support to solve the problems for customers.
4. Provide the return-exchange goods service for no reason.
FAQ
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