PIGMENT RED 170F5RK/ HP RED 2131

What Is PR170F5RK / HP RED 2131

PR170F5RK / HP RED 2131 is an organic pigment with no assigned CAS or CI number, classified as an Organic Pigment type. This specific grade of PR170F5RK is a high-performance red organic pigment designed primarily for industrial coating applications. It delivers a bright, vivid red shade with strong color strength and excellent transparency characteristics. As an organic pigment, it offers superior chemical resistance and lightfastness compared to many conventional red pigments, making it suitable for demanding exterior industrial paint systems where color retention is critical.

Why Choose HP RED 2131

HP RED 2131 stands out as a bright red organic pigment specifically engineered for industrial paints, offering exceptional color purity and vibrancy that enhances the visual appeal of machinery, equipment, and structural coatings. Its advantage lies in delivering high chroma red shades that resist fading under UV exposure, making it ideal for outdoor industrial applications requiring long-term aesthetic performance. Unlike many sibling grades that may offer duller shades or lower durability, HP RED 2131 maintains its brilliance while providing excellent weather resistance and chemical stability. This grade is specifically formulated to perform in solvent-based and waterborne industrial paint systems, giving formulators a reliable option for achieving vivid red colors without compromising on durability. When compared to alternative red 170 variants, this grade offers superior brightness and application consistency.

Key Features

• Delivers exceptionally bright red color with high chroma and saturation for industrial paint formulations.
• Exhibits outstanding lightfastness and weather resistance suitable for long-term outdoor applications.
• Provides excellent chemical resistance against solvents, acids, and alkalis in industrial environments.
• Offers good heat stability during paint manufacturing and curing processes up to 200°C.
• Maintains consistent color strength and dispersion properties across different batch productions.

{
“@context”: “https://schema.org”,
“@type”: “FAQPage”,
“mainEntity”: [
{
“@type”: “Question”,
“name”: “What specific applications does PIGMENT RED 170F5RK (HP RED 2131) perform best in?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “PIGMENT RED 170F5RK is specifically recommended for industrial paints, offering high weather fastness and brilliance color. Its technical profile also supports use in solvent-based and water-based coatings, automotive refinish, industrial coatings, powder coatings, and wood coatings, as well as plastics like PP, PE, PVC, and printing inks including offset and solvent-based inks.”
}
},
{
“@type”: “Question”,
“name”: “What are the key technical properties of PIGMENT RED 170F5RK for paint formulation?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “PIGMENT RED 170F5RK is a blue-shade, semi-transparent Naphthol AS pigment with high tinting strength and brilliance. It provides high weather resistance and light fastness; heat stability is recorded up to specific temperature limits (exact °C available in technical datasheet). Physical properties include defined specific density and resistance to acid and alkali, making it suitable for demanding industrial coating systems.”
}
},
{
“@type”: “Question”,
“name”: “How does PIGMENT RED 170F5RK perform in plastic masterbatch applications?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “PIGMENT RED 170F5RK is recommended for plastics including PP, PE, PVC, and rubber/TPV/TPO. Its high tinting strength allows efficient coloration in masterbatch, while its heat stability ensures processing integrity. The pigment’s brilliance and weather fastness contribute to long-lasting color in outdoor plastic products. Each batch is tested for color strength and dispersibility to ensure consistent plastic performance.”
}
},
{
“@type”: “Question”,
“name”: “What color characteristics does PIGMENT RED 170F5RK exhibit compared to other PR170 grades?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “PIGMENT RED 170F5RK provides a very strong, blue shade tone with semi-transparency. This distinguishes it from yellower or more opaque PR170 variants. Its CI Constitution No. is PR170F5RK, and it delivers high brilliance and color purity, ideal for achieving bright red shades in industrial paints and inks where transparency and vividness are required.”
}
},
{
“@type”: “Question”,
“name”: “Is PIGMENT RED 170F5RK suitable for water-based printing inks and coatings?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Yes, PIGMENT RED 170F5RK is recommended for water-based paints and water-based inks. As a Naphthol AS pigment, it can be formulated into water systems with appropriate dispersants and wetting agents. Its acid and alkali resistance supports stability in water-based binder systems. Each batch undergoes dispersibility testing to confirm performance in waterborne formulations.”
}
}
],
“@id”: “https://www.honorpigment.com/pigment/hp-red-2131-pigment-red-170f5rk/”,
“isPartOf”: {
“@type”: “Article”,
“headline”: “PIGMENT RED 170F5RK Technical FAQ & Performance Data for Paints & Plastics”,
“description”: “Technical FAQ on PIGMENT RED 170F5RK (HP RED 2131): blue-shade Naphthol AS pigment for industrial paints, plastics masterbatch, and printing inks. Includes application data and batch consistency testing.”,
“image”: “https://www.honorpigment.com/wp-content/uploads/pigment-red-170f5rk.jpg”,
“datePublished”: “2025-03-24”,
“author”: {
“@type”: “Organization”,
“name”: “HONOR Pigment”
}
},
“breadcrumb”: {
“@type”: “BreadcrumbList”,
“itemListElement”: [
{
“@type”: “ListItem”,
“position”: 1,
“name”: “Home”,
“item”: “https://www.honorpigment.com/”
},
{
“@type”: “ListItem”,
“position”: 2,
“name”: “Pigments”,
“item”: “https://www.honorpigment.com/pigment/”
},
{
“@type”: “ListItem”,
“position”: 3,
“name”: “PIGMENT RED 170F5RK”,
“item”: “https://www.honorpigment.com/pigment/hp-red-2131-pigment-red-170f5rk/”
}
]
}
}

C.I.NO.: PR170F5RK

Advantage: Bright color

Main Application Recommended: Industrial paints

Product Description – PR170F5RK

HP RED 2131 (PIGMENT RED 170F5RK) is a very strong, blue shade and semi transparent Naphthol AS pigment. which has high weather fastness, high tinting strength and brilliance color. it is recommended in the application of industrial paints, plastics and printing inks.

Recommended Application：

Coatings: solvent based paints, water based paints, automotive refinish, industrial coatings, powder coatings, wood coatings
Plastics: PP, PE, PVC, Rubber/ TPV, TPO
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 PR170F5RK

1. What specific industrial paint applications is PR170F5RK (HP Red 2131) best suited for?

PR170F5RK, known commercially as HP Red 2131, is a high-performance Naphthol AS pigment engineered specifically for industrial paints requiring excellent opacity and a vivid mid-shade red. It excels in solvent-based systems, particularly for coil coatings, general industrial enamels, and protective marine coatings. Its high color strength and clear hue make it ideal for high-visibility safety equipment, agricultural machinery, and heavy-duty transportation finishes where durability against fading is critical. It performs exceptionally well in both air-dry and stoving systems, offering a strong, clean red that resists flooding and floating during application.

2. What are the key performance limits regarding lightfastness and weather resistance for this pigment?

While HP Red 2131 offers excellent resistance for an organic red, it has specific limits. It provides very good lightfastness (typically 7-8 on the Blue Wool scale) in full shade, making it suitable for exterior industrial applications. However, its weather resistance is moderate; in extreme, long-term exterior exposure (e.g., 5+ years in high-UV zones), it may show slight fading or shade change. It is not recommended as a sole pigment for high-gloss automotive topcoats requiring 10-year durability. For maximum weatherability, it is often best used in combination with other pigments or in opaque formulations where the substrate is fully hidden.

3. How does PR170F5RK compare to its sibling variant, PR170F3RK?

The primary difference lies in the chemical finishing and particle size distribution. PR170F5RK is optimized for higher color strength and cleaner, brighter transparency in mass tone, making it more suitable for industrial paints needing vivid, high-impact reds. Its sibling, PR170F3RK, typically offers a slightly yellower, more opaque shade and is often preferred for higher-hiding formulations like architectural coatings. For industrial use, the F5RK grade provides better gloss development and lower mill-base viscosity, allowing for easier processing in high-speed dispersers used in paint manufacturing. The choice depends on whether you prioritize opacity (F3RK) or brilliance and strength (F5RK).

4. Are there any critical processing considerations for incorporating PR170F5RK into industrial paint systems?

Yes. PR170F5RK requires careful dispersion to unlock its full color potential. It is a soft, easily broken-down pigment, but over-dispersion (over-grinding) can lead to a loss of opacity and altered shade. We recommend a medium-energy bead mill dispersion (e.g., zirconia beads, 60-90 minutes) in a high-polarity resin system to achieve a fineness of grind below 10 microns. Avoid prolonged high-shear milling without cooling, as heat can cause recrystallization. Additionally, be aware of potential solubility issues in very strong ketone solvents (like MIBK); a balanced solvent blend (e.g., xylene/butanol) is advised for stable color development.

5. What are the recommended storage conditions and viable substitutions if HP Red 2131 is unavailable?

Store PR170F5RK in a cool, dry environment below 30°C (86°F), away from direct sunlight and moisture. The powder should be kept in sealed, unopened containers; its shelf life is typically 5 years from the production date in original packaging. If HP Red 2131 is unavailable, a direct equivalent is CI Pigment Red 170 (CAS 2786-76-7). While exact shade matches vary, alternatives like Pigment Red 254 (DPP Red) offer much higher weather resistance but at a significantly higher cost, while Pigment Red 112 provides an alternative economy-grade option with lower opacity. Always conduct a trial blend before full substitution to verify paint performance.

HP Red 2131 Takeaway: HP Red 2131 is your go-to, cost-effective workhorse for vibrant, opaque industrial reds, delivering high strength and ease of dispersion for solvent-based paints where excellent lightfastness—but not extreme long-term weatherability—is required.

📩 Need more details?

Request TDS, SDS, or a free sample for testing.