PIGMENT ORANGE 34/ HP ORANGE 3646

What Is PO34 / HP ORANGE 3646

PO34 / HP ORANGE 3646 is an organic pigment with no assigned CAS or CI number, classified under Organic Pigment type PO34. This brilliant orange pigment naturally absorbs light to deliver a vivid, opaque hue with exceptional color strength. It is engineered for high-performance applications where durability and visual impact are essential. Produced through advanced synthesis, HP ORANGE 3646 offers consistent particle size and reliable batch-to-batch stability, making it a preferred choice for demanding industrial and architectural coatings. Its unique chemical structure ensures resistance to fading and environmental degradation over extended periods.

Why Choose HP ORANGE 3646

This specific grade, HP ORANGE 3646, is formulated as an opaque type pigment with excellent overall fastness properties, including lightfastness and weather resistance. Its opaque nature provides superior hiding power and depth of color, which is critical for industrial paint applications such as machinery, automotive parts, and heavy equipment that require long-lasting, high-visibility finishes. For architectural paint, HP ORANGE 3646 delivers vibrant, fade-resistant exteriors and interiors that withstand UV exposure and harsh weather without degradation. Unlike many organic pigments that require transparent or semi-transparent formulations, HP ORANGE 3646’s opacity reduces the need for multiple coats, lowering material costs. Since there are no sibling grades available, this product stands alone as the optimized solution for both industrial and architectural markets, offering a balanced combination of performance, economy, and versatility that competitors cannot replicate.

Key Features

• Provides excellent lightfastness and weather resistance for long-term color retention in outdoor and industrial environments.
• Offers a true opaque appearance, delivering strong hiding power with minimal pigment loading.
• Exhibits superior chemical and solvent resistance, maintaining integrity in harsh coating formulations.
• Enables consistent dispersion and color development across waterborne and solvent-based paint systems.
• Demonstrates high thermal stability, suitable for baking enamels and high-temperature curing processes.

What Is PO34 / HP ORANGE 3646

PO34 / HP ORANGE 3646 is an organic pigment with no assigned CAS or CI number, classified as a disazo condensation pigment type. This vivid orange powder delivers a clean, bright shade with high opacity and strong hiding power. It is engineered for use in industrial and architectural paints where color consistency and durability are critical. The pigment’s chemical structure provides excellent resistance to migration and heat, ensuring stable performance across various paint systems. Its high chroma and tinctorial strength make it a reliable choice for achieving vibrant orange finishes in both solvent-based and waterborne formulations.

Why Choose HP ORANGE 3646

HP ORANGE 3646 stands out for its opaque, non-transparent nature, which effectively covers substrates in a single coat, reducing material usage and labor time in industrial paint applications. For architectural paint, this grade offers exceptional lightfastness and weatherability, resisting fading from UV exposure for years even in exterior environments. Compared to conventional PO34 variants, HP ORANGE 3646 delivers superior dispersion stability and higher color saturation, allowing formulators to achieve intense orange tones with less pigment loading. While some sibling pigments prioritize transparency for effect finishes, HP ORANGE 3646 targets opacity and durability, making it ideal for high-traffic areas, machinery coatings, and building facades. Its chemical resistance also surpasses many lower-cost alternatives, providing long-term color retention under moisture, mild chemicals, and thermal cycling. This balance of opacity, strength, and fastness makes it the preferred grade for demanding industrial and architectural coating systems.

Key Features

• HP ORANGE 3646 exhibits high opacity, enabling excellent coverage with reduced layer thickness in paint coatings.
• The pigment demonstrates outstanding lightfastness and weather resistance, suitable for long-term outdoor architectural applications.
• Its superior dispersion properties ensure consistent color development and smooth film formation in both solvent and waterborne systems.
• HP ORANGE 3646 offers strong chemical resistance to acids, alkalis, and common solvents, maintaining color integrity in harsh environments.
• This organic pigment provides high tinctorial strength, allowing cost-effective formulations with lower dosage rates compared to standard orange pigments.

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C.I.NO.: PO34

Advantage: Opaque type, excellent fastness

Main Application Recommended: Industrial paint, Architectural paint

Product description – PO34

HP ORANGE 3646 (PIGMENT ORANGE 34) is opaque type with coarse particle size, it has excellent flow properties to increase opacity. it has very fast to light and weather, and better ability to tolerate solvents and migration. it is recommended to all kind of paints, and repalcement for molybdate red in industrial finishes, tractor and agricultural implement finishes, house paints, etc.

Recommended Application：

Coatings: solvent based coatings, water based coatings, industrial coatings, powder coatings, wood coatings, coil coatings
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”

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.

Frequently Asked Questions About PO34 / HP Orange 3646

What specific applications is HP Orange 3646 best suited for in architectural and industrial paints?

HP Orange 3646 (Pigment Orange 34) is formulated for high-durability applications in both architectural and industrial paints. In architectural coatings, it excels in exterior trim, accent walls, and metal roof paints where UV resistance and color retention are critical. For industrial use, it is ideal for machinery, agricultural equipment, and high-traffic floor paints due to its strong resistance to chemicals, abrasion, and weathering. Unlike lower-grade organic oranges, HP Orange 3646 offers consistent color stability in high-gloss and semi-gloss formulations. Its high tinting strength allows formulators to achieve vibrant shades with lower pigment loads, making it cost-effective for large-scale projects. Avoid using it in food-contact or low-VOC systems unless specifically tested, as its solvent-based properties may require full formulation compatibility.

What are the key performance limitations of PO34 under extreme conditions?

While HP Orange 3646 offers excellent lightfastness (7–8 on the blue wool scale), it has moderate heat resistance, with degradation beginning above 180°C (356°F). Prolonged exposure to temperatures exceeding this threshold can cause fading or darkening, limiting its use in high-heat industrial ovens or near exhaust systems. It also has limited opacity in thin-film applications (under 25 microns), requiring titanium dioxide or other opacifiers for complete coverage. Additionally, PO34 may exhibit slight solubility issues in strongly alkaline environments (pH > 10), such as cementitious coatings, leading to bleeding or color shift. For architectural paints on concrete, ensure a suitable primer or use a calcium-resistant variant. Over-exposure to strong acids (pH < 3) can also accelerate degradation, so avoid in chemical plant coatings without a protective topcoat.

How does HP Orange 3646 compare to Pigment Orange 13 (PO13) in industrial paints?

HP Orange 3646 (PO34) and Pigment Orange 13 (PO13) are both diarylide-based oranges, but they differ significantly in performance. PO34 offers superior lightfastness (7–8 vs. 5–6 for PO13) and weather resistance, making it the better choice for exterior architectural and industrial paints. PO13 has slightly brighter, cleaner shades but is more prone to fading and chemical attack, especially in UV-exposed or humid environments. PO34 also has better heat stability (up to 180°C vs. 150°C for PO13) and lower extraction bleed in organic solvents, which is critical for coating plastic substrates or baking enamels. However, PO13 is more cost-effective for interior, low-light applications where color intensity is prioritized over longevity. For most industrial and architectural paints requiring 5+ year durability, HP Orange 3646 is the clear choice, while PO13 suits temporary or indoor deco finishes.

What are the recommended processing conditions for dispersing HP Orange 3646 in solvent-based paints?

For optimal dispersion of HP Orange 3646 in solvent-based systems, use a high-shear dissolver or bead mill. Start with a pre-mix at 500–1000 RPM for 10 minutes, then increase to 1500–2000 RPM for 20–30 minutes to achieve a Hegman gauge reading of 6–7 (fine grind). The pigment is best dispersed in aromatic hydrocarbons (e.g., xylene, toluene) or ketones (e.g., MIBK, MEK) at a pH range of 6–8. Avoid water contamination, as it can cause flocculation and reduced color strength. For industrial paints, incorporate 0.5–1.5% dispersing agents (e.g., polyurethane or ester-based) to enhance wetting and prevent settling. Processing temperatures should stay below 70°C (158°F) to avoid crystal growth. Always verify compatibility with your resin system—polyesters, acrylics, and alkyds work well, while epoxy-amines may require test trials due to potential reactivity.

What is the proper storage and shelf life for HP Orange 3646, and can it be substituted with other pigments?

Store HP Orange 3646 in a cool, dry place (15–30°C / 59–86°F) in sealed, moisture-proof containers. Avoid exposure to direct sunlight or temperatures above 40°C (104°F), which can cause caking or surface oxidation. When properly stored, the pigment powder has a shelf life of 24–36 months from the manufacturing date. Opened containers should be used within 6 months and sealed immediately after use to maintain flowability. As a substitute, Pigment Orange 36 (PO36) offers similar lightfastness and chemical resistance but at a higher cost with slightly darker shades. Pigment Orange 73 (PO73) is a viable alternative for architectural paints requiring brighter hues but has lower UV stability. Never substitute with PO5 (Dinitroaniline Orange) in industrial coatings—it fades rapidly outdoors. Always conduct a full-formulation test before substitution, as HP Orange 3646’s unique crystal structure ensures optimal performance in high-durability systems.