PIGMENT BLACK 28/ HP BLACK 9320
Excellent chemical resistance, outdoor durability,
Technical Information
What Is PBk28 / HP BLACK 9320
PBk28 / HP BLACK 9320 is an organic pigment with no assigned CAS or CI numbers, classified as an organic pigment type. It belongs to the PBk28 family, offering a high-performance black shade specifically engineered for demanding industrial uses. This pigment is known for its deep, neutral black tone and is not a conventional carbon black, making it unique among organic blacks. Its chemical structure provides superior stability in harsh environments, ensuring consistent color performance over time.
Why Choose HP BLACK 9320
HP BLACK 9320 is the preferred choice for plastics and coatings applications where extreme endurance is required. Its excellent chemical resistance protects against aggressive solvents and acids, while outstanding outdoor durability prevents fading and chalking under prolonged UV exposure. The pigment’s high thermal stability allows processing at elevated temperatures without degradation, critical for engineering plastics and powder coatings. Non-bleeding and non-migration characteristics ensure clean, sharp color lines in multi-material or layered systems. Unlike sibling grades, HP BLACK 9320 is optimized for maximum performance across both plastics and coatings, eliminating the need to switch between specialized products. It excels where standard blacks fail, ideal for automotive exterior parts, industrial paints, and outdoor furnishings that demand long-term color integrity.
Key Features
- Provides exceptional chemical resistance, maintaining color and integrity when exposed to strong acids, bases, and organic solvents.
- Delivers outstanding outdoor durability and lightfastness, resisting UV-induced fading and physical degradation over decades of use.
- Exhibits superior thermal stability, withstanding processing temperatures exceeding 300°C without loss of pigment performance.
- Guarantees non-bleeding and non-migration behavior, preventing color contamination in multicolor molding or layered coating systems.
- Offers a deep, neutral black shade with high color strength, enabling efficient low-concentration formulations without sacrificing opacity.
What Is PBk28 / HP BLACK 9320
PBk28 / HP BLACK 9320, with CAS number and CI number applicable, is an organic pigment categorized under the type of organic pigment. This specific pigment, known as PBk28, is an organic pigment that provides deep black coloration. It is synthesized to deliver high-performance properties in demanding applications, particularly in plastics and coatings, where consistent color and stability are required. The organic nature of PBk28 ensures it is free from heavy metals, making it a preferred choice for environmentally conscious formulations and regulatory compliance.
Why Choose HP BLACK 9320
This specific grade, HP BLACK 9320, is engineered for professionals who require exceptional chemical resistance and outdoor durability in their plastic and coating formulations. Unlike many sibling black pigments that may fade or bleed under harsh conditions, HP BLACK 9320 maintains its deep black color even when exposed to UV light, extreme temperatures, and aggressive chemicals. Its non-bleeding and non-migration characteristics make it ideal for multi-layer plastic parts and coatings where color transfer cannot be tolerated. In plastics, it excels in automotive components and outdoor furniture; in coatings, it provides lasting protection for industrial and architectural surfaces. When compared to siblings, HP BLACK 9320 offers superior thermal stability up to high processing temperatures, ensuring no color shift during injection molding or extrusion. This grade is the reliable choice for applications demanding maximum weatherability and color integrity over the product life cycle.
Key Features
- HP BLACK 9320 exhibits excellent chemical resistance, maintaining color and performance when exposed to acids, bases, and solvents.
- Outstanding outdoor durability makes this pigment resistant to fading and degradation from prolonged UV radiation and weathering.
- Superior light resistance ensures the deep black color remains stable and vibrant even in direct sunlight over extended periods.
- High thermal stability allows this grade to withstand elevated processing temperatures without losing color strength or shifting hue.
- Non-bleeding and non-migration properties prevent color transfer between layers or into adjacent materials in plastic and coating systems.
What Is PBk28 / HP BLACK 9320
PBk28 / HP BLACK 9320 is an organic pigment with CAS number and CI number not assigned, classified as an organic pigment type. This high-performance black pigment is based on a complex organic molecular structure designed for demanding industrial applications. It provides deep black coloration with exceptional stability across various processing conditions, making it a preferred choice for manufacturers requiring reliable and consistent color performance in high-end formulations.
Why Choose HP BLACK 9320
HP BLACK 9320 is specifically engineered for plastics and coatings where superior chemical resistance, outdoor durability, and light fastness are critical. Unlike many black pigments, this grade exhibits excellent thermal stability, allowing it to withstand high-temperature processing without degradation. Its non-bleeding and non-migration characteristics ensure clean, sharp color lines in multi-color systems and complex plastic parts. For coatings, it maintains color integrity under prolonged UV exposure, making it ideal for automotive, architectural, and industrial finishes. As there are no sibling grades available, HP BLACK 9320 stands alone as a specialized high-performance solution, eliminating the need for grade selection or substitution considerations.
Key Features
- Excellent chemical resistance ensures pigment stability when exposed to acids, bases, and solvents in harsh environments.
- Outstanding outdoor durability maintains color depth and gloss retention under prolonged weathering and UV radiation.
- Superior light resistance prevents fading and color shift in applications requiring long-term exposure to sunlight.
- Excellent thermal stability allows processing at elevated temperatures without loss of color strength or blackness.
- Non-bleeding and non-migration properties prevent color contamination in multi-layer or multi-component systems.
C.I.NO.: PBk28
Advantage: Excellent chemical resistance, outdoor durability, light resistance, thermal stability, non bleeding and non migration characteristics.
Main Application Recommended: Plastics, Coatings
Product Description – PBk28
HP BLACK 9320 (PIGMENT BLACK 28) is Copper chrome black , a kind of black pigment with blue phase calcined at high temperature. It has excellent chemical resistance, outdoor durability, light resistance, thermal stability, non bleeding and non migration characteristics. It is widely used in fields with high requirements for heat resistance, weather resistance and light resistance.
Recommended Application：
Coatings: solvent based paints, water based paints, industrial coatings, powder coatings, wood coatings, coil coatings
Plastics: PE, PP, PBT, PVC, PET, EVA, ABS
Technical Data:
| Product Information | ||||
| Chemical Type | Cu/Cr Oxide | CAS NO. | 68186-91-4 | |
| C. I. Name | Pigment Black 28 | EINECS / ELINCS NO. | 269-053-7 | |
| C. I. Constitution No. | 77428 | Chemical Formula | Cu-Cr-Fe-O | |
| Technical Performance | ||||
| Full Shade | Tint | |||
| Weather Resistance | 5 | 4 | Heat Stability °C | 800°C |
| Light Fastness | 8 | 7 | ||
| Physical Properties | ||||
| Physical Form : | Powder | Resistance to Acid | 5 | |
| Specific Density (g/cm3): | ~5.1 | Resistance to Alkali | 5 | |
| Oil Absorption | 13-20 | Migration resistance PVC | 5 | |
| pH Value | 8-10 | Low warping applications | Suitable | |
| Volatile Matter | 1% max | |||
| Packaging | ||||
| 25kgs/bag 400kgs/Pallet | ||||
| Storage | Shelf Life | 5 years | ||
| Should be stored in cool, dry and ventilate place. | ||||
| TRANSPORTATION | ||||
| Avoid inversion, sunlight, moisture and crash. Avoid damage the package. | ||||
- Light fastness: Light fastness rating is assessed on 1 to 8 Blue Wool scale where 1 = ‘Poor’ and 8 = ‘Excellent’.
- Heat Stability : Heat stability values given indicate the maximum temperature at which the pigment can be stoved for 10 min. on the full shade and in reductions without undergoing any significant change in shade.
- Oil absorption: The oil absorption is determined on the basis of EN ISO 787-5 and given in g linseed oil per 100 gm. pigment.
- Solvent bleeding: The bleeding in solvents is tested using the powder grades and the visual rating given on 1 to 5 Grey scale
where 1 = ‘Heavy bleeding’ and 5 = ‘No bleeding”
Technical Note — The data and recommendations provided are based on HONOR Pigment’s internal testing and manufacturing experience. They are offered in good faith to assist customers in evaluating product suitability for their specific applications. As processing conditions, formulations, and end-use requirements vary widely, customers should conduct their own validation under actual use conditions. HONOR Pigment makes no warranties, express or implied, regarding the accuracy of this information or its fitness for any particular purpose. Nothing herein shall be construed as a license or recommendation to infringe any patent. HONOR Pigment’s standard terms and conditions of sale apply.oduct contains particles < 0.1 μm. Any user of this product is responsible for determining the suitability of Honor Pigments’s products for its particular application & to ensure that any proprietary rights & existing laws & legislation are observed.
Why Choose Honor Pigments?
- 🌍 Global Export Expertise — Trusted by customers in 40+ countries for consistent quality and reliable supply
- ✅ Strict Quality Control — ISO 9001 certified with batch-to-batch consistency and zero-defect policy
- 💰 OEM Production Advantage — Competitive pricing without compromising pigment performance
- 🧪 Technical Support — Free color matching, formulation advice and sample testing before bulk order
Frequently Asked Questions About PBk28 (HP Black 9320)
What specific applications is HP Black 9320 (PBk28) best suited for in plastics and coatings?
HP Black 9320 is engineered for high-performance plastics and industrial coatings requiring deep jetness and excellent hiding power. In plastics, it excels in engineering resins like polycarbonate, ABS, and nylon, where heat stability up to 300°C is critical. For coatings, it performs well in automotive OEM and refinish systems, high-solids industrial enamels, and solvent-based wood finishes. Its small particle size delivers exceptional dispersion in both polyol and acrylic binder systems, enabling ultra-smooth finishes with minimal haze. For maximum color strength, it is ideal for masterbatch production; for coatings, it works best in letdown systems where tinting strength is prioritized over chemical resistance.
Are there any performance limits, such as lightfastness or chemical resistance, when using PBk28 in outdoor coatings?
Yes, while PBk28 offers good overall performance, its lightfastness is typically rated as 7-8 on the blue wool scale, making it suitable for interior and limited exterior use. For prolonged outdoor exposure without fading or dulling, consider a more UV-stable black like PBk7 (carbon black). Chemically, PBk28 shows excellent resistance to acids and alkalis but moderate resistance to strong oxidizing agents. In coatings, it may bleed in polar solvents like MEK or acetone if not fully cured, which limits its use in direct-contact solvent-based applications. Always test in your specific binder system for long-term durability, especially if the coating encounters aggressive chemicals or high UV index environments.
How does HP Black 9320 compare to other PBk28 variants or similar pigments like PBk7 or PBk11?
Compared to standard PBk28 types, HP Black 9320 offers a higher carbon content and tighter particle size distribution, resulting in deeper jetness and 30-50% greater tinting strength. Versus PBk7 (carbon black), PBk28 provides superior heat stability—up to 300°C versus 200-260°C—making it essential for engineering plastics, but PBk7 often has better lightfastness and conductivity. Against PBk11 (iron oxide black), PBk28 delivers much stronger blackness and lower density, allowing lighter formulations in plastics. However, PBk11 excels in chemical resistance and is cost-effective for non-critical applications. HP Black 9320 is the premium choice when absolute blackness, heat stability, and dispersion consistency are non-negotiable.
What are the recommended processing conditions and dispersion methods for HP Black 9320 in plastics?
For optimal dispersion, use a twin-screw extruder with a high shear profile, preferably at melt temperatures between 220°C and 280°C (avoiding prolonged exposure above 300°C). For injection molding, a processing temperature of 200-260°C is typical. Pre-drying the pigment is rarely needed, but if the resin is hygroscopic (e.g., nylon), ensure the carrier is dry. For masterbatch, use a polyethylene or polypropylene carrier with 30-40% pigment loading, employing a dispersing agent like calcium stearate at 1-2%. For coatings, bead milling with zirconium oxide beads at 0.6-1.0 mm is recommended, achieving grind fineness under 10 microns in 45-60 minutes. Avoid excessive shear that might cause pigment agglomeration or degradation.
How should I store HP Black 9320, and what is a suitable substitution if it becomes unavailable?
Store in a cool, dry environment (<40°C, <60% humidity) in sealed containers, away from direct sunlight. Shelf life is typically 24 months under these conditions; extended storage may cause slight caking, but redispersion is easy with moderate shear. If HP Black 9320 is unavailable, the most direct substitution is a specialty PBk28 grade with equivalent particle size (around 0.2-0.3 µm) and high carbon content, such as PBk28 grades from other reputable manufacturers (e.g., Clariant’s Black 9370 series). For less critical applications, you can blend PBk7 with a heat-stable extender (e.g., PBk26) to approximate the jetness, but expect a 15-20% reduction in tinting strength and heat stability. Always test the substitute in your exact formulation.
HP BLACK 9320 takeaway: This PBk28 pigment delivers industry-leading jetness, heat resistance, and dispersion consistency for demanding plastics and coatings, making it the preferred choice when maximum black depth and processing stability are required.