To choose the right pigment for coatings and paints, start by matching the pigment’s chemical family and surface treatment to your resin system, application method, and exposure conditions. Water-based formulations demand pigments with robust pH stability (pH 5–9) and good wetting characteristics. Solvent-based systems require pigments with solvent resistance grade 4–5 to prevent bleed and bloom. Powder coatings need pigments that withstand curing temperatures above 200°C without discoloration. Automotive topcoats impose the strictest requirements: weather resistance grade 4–5 and lightfastness rating 7–8 on the Blue Wool scale. The table below maps each coating type to the optimal pigment families and specific CI codes.

Coating-Type Selection Table

Key Pigment Families by Application

High-Performance Automotive Pigments

For automotive OEM and premium refinish applications, pigment selection directly determines long-term appearance. PR254 (DPP Red) from our HP RED 2135 series delivers exceptional weather resistance and color saturation — making it the industry-standard red for automotive topcoats. PR254 exhibits lightfastness 8 on the Blue Wool scale and weather resistance grade 5 after 2000+ hours of Florida exposure. For violet and magenta effects, PV19 (Quinacridone Violet) and PR122 (Quinacridone Magenta) provide outstanding durability in tri-coat systems.

Cost-Effective Industrial Pigments

For industrial OEM coatings where cost-per-liter governs formulation decisions, PR101 (Iron Oxide Red) offers the best price-performance ratio with lightfastness 8, weather resistance 5, and heat stability exceeding 500°C. PB15:3 (Phthalocyanine Blue, beta crystal) is the workhorse blue pigment across all industrial coating types — compatible with alkyd, acrylic, epoxy, and PU resin systems at loadings from 2–15%. Both PR101 and PB15:3 are REACH-registered and available in our economy (HP ECO) and standard (HP STD) grades.

Water-Based Coatings — pH Stability and Dispersion

Water-based formulations present two unique challenges for pigment selection. First, the aqueous medium has a pH that can drift from 5 to 9 during processing and shelf life, and pigments must remain chemically stable throughout this range. Phthalocyanines (PB15:3, PG7) are inherently pH-stable; iron oxides (PR101, PY42, PBk11) are excellent; DPP pigments (PR254) require surface-treated grades for long-term stability. Second, pigment wetting and dispersion are more difficult in water than in organic solvents — choose pigments with dedicated aqueous surface treatments (sulfonated or acrylic-modified grades).

Coil Coating Selection — The 300°C Challenge

Coil coating applications subject pigments to peak metal temperatures (PMT) of 230–300°C for 30–60 seconds. Only specific pigment chemistries survive this thermal shock without shade drift or degradation:

• Complex Inorganic Color Pigments (CICP) — PBr24 (chrome antimony titanate), PBk28 (copper chromite black), PBr101 — these mixed-metal oxides withstand >500°C and are the most reliable choice for coil.
• Solvent-Stable Phthalocyanines — PB15:3 and PG7 in coil-grade variants that resist recrystallization in PVDF and high-solids polyester systems.
• Bismuth Vanadate Yellow (PY184) — An inorganic yellow that combines high chroma with coil-grade heat stability; does not release heavy metals during cure.
• DPP Red (PR254) High-Temp Grade — Our HP RED 2135-HT variant maintains ΔE < 1.0 after 300°C/60 s exposure.

Frequently Asked Questions

Q: What is the best pigment for exterior house paint?

For exterior architectural paints, PR101 (Iron Oxide Red) and PY42 (Iron Oxide Yellow) offer the best weather resistance and cost value. For deep shades, PB15:3 (phthalocyanine blue) and PG7 (phthalocyanine green) deliver excellent durability. Avoid monoazo pigments (PR112, PY1, PY74) in exterior formulations — they show unacceptable fading within 12–18 months of exposure. For premium exterior lines, PR254 (DPP red) and PY150 (benzimidazolone yellow) extend color retention to 10+ years.

Q: How do I avoid pigment settling in water-based coatings?

Settling in water-based coatings is controlled through a combination of pigment selection and formulation strategy. First, select pigments with surface treatments designed for aqueous media (look for grades with “W” or “AQ” suffix). Second, use a high-shear disperser to achieve Hegman grind ≥7 for organic pigments and ≥6 for inorganic pigments. Third, incorporate anti-settling rheology modifiers: bentonite organoclays for solvent-free systems, or fumed silica + associative thickener combinations for latex paints. Fourth, maintain zeta potential >|25 mV| at the target pH through dispersant optimization. Our technical team can recommend the optimal dispersant package for each pigment grade in our portfolio.

Q: What pigments survive 300°C coil coating cure?

The following pigment chemistries reliably survive 300°C coil coating cure without shade drift: CICPs including PBr24 (chrome antimony titanate buff), PBk28 (copper chromite black), and PBr101 (mixed metal oxide brown); PB15:3 and PG7 in solvent-stable coil grades (crystal-stabilized against recrystallization in PVDF resin); PY184 (bismuth vanadate yellow) with high-temp surface encapsulation; and our HP RED 2135-HT (PR254 high-temp grade) which achieves ΔE < 1.0 after 300°C/60-second exposure. Avoid entirely: monoazo yellows (PY1, PY3, PY74), diarylide yellows (PY12, PY13, PY83), and any pigment with a sublimation temperature below 300°C (check our TDS for sublimation data).