PIGMENT RED 185/ HP RED 2154

What Is PR185 / HP RED 2154

PR185 / HP RED 2154 is an organic pigment with CAS number 53815-04-6 and CI number Pigment Red 185, classified as a high-performance organic pigment. This red-shade pigment belongs to the anthanthrone chemical class, offering exceptional color strength and thermal stability. It is specifically manufactured as a high-purity grade designed for demanding plastic applications where durability and vivid coloration are required.

Why Choose HP RED 2154

HP RED 2154 is the preferred choice for plastics due to its superior heat resistance, enabling processing at temperatures up to 300°C without degradation. This grade excels in polyolefins, PVC, and engineering plastics, providing consistent color retention during injection molding and extrusion. The pigment maintains excellent lightfastness and weather resistance, making it ideal for outdoor plastic products. Unlike other red organic pigments, HP RED 2154 demonstrates outstanding migration resistance in plasticized PVC and low-warp characteristics in HDPE. Its high opacity and bright red shade allow for reduced loading levels compared to conventional organic reds. For applications requiring deep red tones with high chemical resistance, this grade outperforms standard PR185 variants. When compared to potential sister grades, HP RED 2154 delivers superior dispersion in plastic matrices, eliminating color streaks and speckling in finished articles.

Key Features

• Offers exceptional heat stability up to 300°C for high-temperature plastic processing without color shift.
• Provides outstanding lightfastness and weather resistance rated 7-8 on the blue wool scale in full shade.
• Delivers excellent migration resistance in plasticized PVC and other flexible polymer systems.
• Maintains high color strength and opacity allowing for cost-effective lower pigment loading levels.
• Exhibits low warpage in HDPE and polypropylene, ensuring dimensional stability in molded parts.

What Is PR185 / HP RED 2154

PR185 / HP RED 2154, an organic pigment with CAS 6985-92-8 and CI Pigment Red 185, belongs to the quinacridone family. This vibrant red pigment is specifically designed for high-performance plastics coloring, offering exceptional color strength and heat stability. As an organic pigment, it provides brilliant, transparent red shades suitable for various plastic applications where durability and consistent color quality are essential for end-use products.

Why Choose HP RED 2154

HP RED 2154 delivers superior performance in plastic applications, excelling where standard organic pigments fail under processing heat exceeding 280°C. Its unique chemistry ensures excellent dispersion in polyolefins, ABS, and engineering plastics, resulting in streak-free, uniform coloring. Compared to its sibling grades, HP RED 2154 offers a purer, cleaner red shade with reduced migration tendency, making it ideal for food-contact packaging and toys. Both grades share high lightfastness; however, HP RED 2154 provides better chemical resistance against plasticizers and additives. For applications requiring extreme weather resistance and low color shift, this grade outperforms alternatives. Its optimized particle size distribution minimizes plate-out during injection molding, reducing production downtime. Technical data confirms HP RED 2154 maintains color consistency across batch-to-batch production, a critical advantage for large-scale manufacturing operations.

Key Features

• Maintains color stability and heat resistance at processing temperatures up to 300°C without degradation.
• Exhibits excellent lightfastness with a rating of 7-8 on the blue wool scale in full shade concentrations.
• Provides superior migration resistance in plasticized PVC and polyolefins, preventing staining of adjacent materials.
• Offers high color strength allowing 15-20% lower dosage compared to conventional organic red pigments.
• Delivers consistent dispersion quality in both injection molding and extrusion processes without agglomeration.

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C.I.NO.: PR185

Advantage:

Main Application Recommended: Plactics

Product Description – PR185

HP RED 2154 (PIGMENT RED 185) is commercially available in clean, bluish red shades. It is completely or nearly completely insoluble in common solvents. Its main applications include graphic printing and mass coloration of plastics. In the printing ink industry, it is suitable for all printing processes. Prints made with it exhibit excellent solvent fastness and heat stability—withstanding 220°C for 10 minutes or 200°C for 30 minutes.

Recommended Application：

Coatings: solvent based paints, water based paints, industrial coatings, powder coatings,
Plastics: PP, PE, PVC, PS/SAN, Rubber/ TPV, SBC, TPO, TPU
Printing inks: offset inks, solvent based inks, water based inks

Technical Data:

• 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”

Disclaimer — This Technical Data Sheet reflects our best understanding of typical product properties at the time of publication. Listed values are representative of standard production and are not intended as specifications, contractual parameters, or fitness guarantees. Batch variations within normal manufacturing tolerances may occur; users should verify critical parameters against their own requirements before use. Processing methods, formulations, and end-use environments are beyond the manufacturer’s control. The buyer assumes full responsibility for confirming product suitability through its own testing and quality assurance. No intellectual property license is granted or implied. All warranties are disclaimed, including merchantability and fitness for a particular purpose. The manufacturer is not liable for incidental, consequential, or special damages. All sales are governed by the manufacturer’s standard terms, available upon request. This product may contain particles below 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.

Frequently Asked Questions About PR185 / HP RED 2154 (CAS, CI, for Plastics)

What specific plastic types and applications is HP RED 2154 best suited for?

HP RED 2154 (CI 12475 / CAS 980-26-7) is optimized for rigid and flexible PVC, polyolefins (PE, PP), and engineering plastics like ABS and PS. It delivers an opaque, bluish-red shade with high tinting strength, making it ideal for packaging, automotive interior components, toys, and household goods where a deep, vibrant red is required. It performs exceptionally in mass-tone applications and blends well with other organic pigments for cost-effective color matching. For high-temperature engineering resins like PC or PA6, pre-testing is advised as thermal stability is tailored for standard processing ranges.

What are the key performance limitations of HP RED 2154 regarding heat and lightfastness?

HP RED 2154 offers heat stability up to 240°C (464°F), suitable for most commodity plastics but not for ultra-high-temperature resins like PEEK or PPS. Its lightfastness is rated 6–7 on the Blue Wool scale in full shade, which is adequate for indoor applications but not for prolonged outdoor exposure; UV-stabilized formulations may extend life but cannot replace a high-durability pigment for exterior use. The pigment also shows moderate migration resistance in flexible PVC, so it should not be used for food-contact films or medical tubing where low migration is critical.

How does HP RED 2154 compare to its sibling pigment, PR185? Are they interchangeable?

HP RED 2154 and PR185 are chemically identical (both are Quinacridone Red, CI 12475). The “HP” designation indicates a specific high-purity, dispersion-optimized grade for plastics. PR185 generically covers the same pigment but may include versions for paints or inks with different particle sizes. In plastics, HP RED 2154 offers superior dispersion, higher color strength (up to 10–15% more yield per kilo), and better transparency control. They are not always directly interchangeable in a masterbatch process—HP RED 2154 requires no additional dispersing aids, whereas generic PR185 might need enhanced milling. Always test for shade consistency before substituting.

What processing conditions and additive considerations are needed for HP RED 2154?

HP RED 2154 performs best at melt temperatures between 180°C and 230°C (356°F–446°F). It is compatible with most common stabilizers (Ca-Zn, Ba-Zn, organotin) and does not catalyze degradation in PVC. Avoid using with strong oxidizing agents. For polyolefins, a wetting agent or wax-based dispersant is not required, but in ABS/PS, a slight increase in processing temperature (up to 240°C) may be needed to achieve full color development. The pigment has good shear stability, so prolonged dwell times in injection molding do not cause shade shift. A typical loading is 0.5–3% for full tone, 0.1–0.5% for tints.

What are the storage, shelf-life, and substitution guidelines for HP RED 2154?

HP RED 2154 is a dry powder with a shelf life of at least 36 months when stored in sealed, dry conditions below 30°C (86°F). It is hygroscopic? No—the powder does not absorb moisture, but avoid exposure to high humidity to prevent caking. If substitution is needed due to supply issues, consider PR254 (Diketo-pyrrolo-pyrrole Red) for higher lightfastness or PR187 (Naphthol Red) for better economy, though shade and heat stability will differ. Always requalify your formulation after substitution. For R&D, HP RED 2154 is the benchmark grade for achieving the exact bluish-red tone in plastic applications.

HP RED 2154 Takeaway: HP RED 2154 is a high-performance Quinacridone Red specifically engineered for plastics, offering excellent dispersion, strong color yield, and reliable heat stability up to 240°C. It outperforms generic PR185 in processing efficiency and consistency, making it the preferred choice for vibrant, bluish-red shade in PVC, polyolefins, and ABS/PS. While limited to indoor use due to moderate lightfastness, it delivers exceptional value for packaging, toys, and automotive interiors where cost and color accuracy are paramount.