Pigment Yellow 151 (PY151) Buyer Checklist: Specs, Fastness, and Qualification
Specs and buyer checklist for Pigment Yellow 151 (HP Yellow 1618): fastness, heat stability, applications, and what to request before approval.
Pigment Yellow 151 (PY151) Buyer Checklist: Specs, Fastness, and Supplier Qualification

When a formulation is close to final approval, the question isn’t “Is Pigment Yellow 151 a good pigment?” It’s: Is this specific PY151 grade consistent, documented, and stable in our system—at the heat, resin chemistry, and service conditions we ship? This short checklist is written for procurement and technical stakeholders qualifying PY151—specifically HP Yellow 1618—for coatings, plastics, and solvent/water-based inks. Whether you’re formulating for German automotive OEM coatings, blending in Brazil for architectural paints, or qualifying in Japan for engineering plastics, the qualification rigor must be consistent.
HP Yellow 1618 (PY151) Quick Reference Specifications
| Property | Value |
|---|---|
| Chemical type | Benzimidazolone |
| CAS | 31837-42-0 |
| C.I. Name / Constitution No. | Pigment Yellow 151 / 13980 |
| Physical form | Powder |
| Heat stability | 260°C (ISO 787-24) |
| Light fastness (full shade / tint) | 8 / 7 (Blue Wool Scale, ISO 105-B02) |
| Weather resistance (full shade / tint) | 5 / 5 |
| Acid / alkali resistance | 5 / 5 |
| Migration resistance (PVC) | 5 |
| Oil absorption | 55 g linseed oil / 100 g pigment |
| pH | 5.0–8.0 |
| Volatile matter | 1% max |
| Packaging | 10 kg/bag; 300 kg/pallet |
| Shelf life | 5 years (cool, dry, ventilated storage) |
Five Qualification Buckets for PY151 Approval
Decision-stage qualification typically comes down to five buckets. If any one fails, you lose time in rework, re-approval, or customer color disputes—especially in Southeast Asian high-volume manufacturing where production downtime is measured in minutes.
1) Fastness Targets for Your End-Use
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Lightfastness and weathering: critical for outdoor coatings and exposed plastics—a key parameter for Korean coil coating exporters shipping to sun-intensive markets
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Heat stability: 260°C peak; validate at your actual processing temperature per ISO 787-24
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Acid/alkali resistance: rated 5/5; note that strong alkaline environments can be a risk factor per PCI Magazine’s evaluation
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Migration/bleed behavior: rated 5 in PVC; validate in multi-layer systems
2) Dispersion Behavior and Color Development
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Confirm dispersibility in your typical mill/base resin; validate time to reach target fineness (Hegman per ASTM D1210)
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HP Yellow 1618 lists good dispersibility—still validate in your own process window
3) Batch-to-Batch Consistency and Traceability
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Batch-specific COA (not generic sheet); consistent lot numbers and test methods; clear change-control approach
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Critical for German and Japanese manufacturers with rigorous supplier audit processes
4) Documentation Pack Readiness
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SDS, TDS, COA per batch—non-negotiable for global shipments and audits
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For REACH/RoHS compliance in the EU market, request the latest SVHC statement
5) Supply Reliability and Total Landed Cost
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Confirm packaging (10 kg/bag), lead time, MOQ, and transit times to Brazil, Southeast Asia, and Korea
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Unit price is rarely the full story—include shipping lane performance and documentation speed
PY151 Application Fit: Where It Excels
HP Yellow 1618 is positioned for:
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Coatings: solvent-based and water-based paints, industrial coatings, coil coatings, automotive paints, wood coatings—browse our pigments for coatings
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Plastics: PP, PE, PVC, PS/SAN, ABS, PET, PBT, TPU—compare with Pigment Yellow 191 in Plastics for heat-resistance benchmarks
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Printing inks: solvent-based and water-based inks—see Pigment Yellow 14 for solvent-based inks
PY151 is often selected when you need a clean greenish-yellow with durability—a profile demanded across Southeast Asian industrial coating operations, Brazilian automotive paint formulators, and German high-performance plastics manufacturers.
⚠️ Warning: Strong alkaline conditions can increase shade shift risk for some organic pigment systems. If considering powder coatings or alkaline-curing environments, verify early.
PY151 Frequently Asked Questions
What is Pigment Yellow 151 used for?
Pigment Yellow 151 (PY151) is a benzimidazolone yellow pigment used in solvent-based and water-based coatings (industrial, automotive, coil, wood), plastics (PP, PE, PVC, ABS, PET), and printing inks. It provides a clean greenish-yellow shade with strong durability. See the HP Yellow 1618 product page for grade-specific data.
What is the heat resistance of PY151?
HP Yellow 1618 (PY151) has a published heat stability of 260°C, tested per ISO 787-24. This makes PY151 suitable for most coatings bake cycles and commodity plastics processing (HDPE/PP). For higher-temperature engineering plastics (PC at 300°C+), consider Pigment Yellow 191 or Pigment Yellow 110.
What is the lightfastness of PY151?
PY151 achieves Blue Wool Scale 8 in full shade and 7 in tint, tested per ISO 105-B02 xenon arc lamp exposure. This places PY151 among the most lightfast benzimidazolone yellows, suitable for exterior automotive and coil coating applications requiring multi-year color retention.
What documents do I need to qualify a PY151 supplier?
Minimum documentation package: SDS, TDS, and batch-specific COA for the exact grade (HP Yellow 1618). For EU buyers, also request the latest REACH/SVHC compliance statement. Batch traceability (lot numbers matching across COA, label, and shipping docs) is non-negotiable for ISO 9001 / IATF 16949 supply chains.
How does PY151 compare to PY110 and PY138?
PY151 (benzimidazolone, greenish-yellow, 260°C) offers a different shade direction from PY110 (isoindolinone, reddish-yellow, 290°C) and PY138 (quinophthalone, greenish-yellow, 280°C). PY151 provides the best balance of lightfastness (Grade 8) and tinting strength among greenish-yellow options. Compare all three: PY110 Guide and PY138 Buyer Guide.
Next Step: Request PY151 Documentation and Samples
If you’re qualifying HP Yellow 1618 (PY151), request the full documentation pack (SDS/TDS/COA), packaging details, pricing, and lead time. You can contact Honor Pigments or email info@honorpigment.com.
📦 Ready to qualify PY151? Request your free sample kit and full documentation pack today. Fast turnaround for German, Brazilian, Japanese, Korean, and Southeast Asian buyers—samples shipped within 48 hours. Contact Honor Pigment →
Disclaimer: This article is for general reference only. Always verify specifications with our team and review the current full legal disclaimer, TDS and SDS before product use.
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