PREMIUM TOPCOAT 501

What is ALEXSEAL PREMIUM TOPCOAT 501 and why choose it?

ALEXSEAL PREMIUM TOPCOAT 501 is a professional two-component, polyurethane-based coating developed specifically for the yacht industry. It is designed for both exterior and interior applications on areas not subjected to permanent water immersion. Once cured, it delivers a high-gloss wet look with superior distinction of image, helping to preserve the yacht’s appearance and value while reducing cleaning and maintenance effort.

The system offers excellent gloss and colour stability even under extreme climatic conditions and shows high resistance to UV radiation, salt water, abrasion and fuel.

Main features

• Two-component polyurethane topcoat for professional use.
• High-gloss, wet-look finish with superior distinction of image.
• Developed for the yacht industry; suitable for exterior and interior areas not under permanent water immersion.
• Excellent gloss and colour stability under extreme weather conditions.
• High resistance to UV rays, salt water, abrasion and fuel.
• Usable by spray, brush or roller, including roll-only application with dedicated additives.
• Available in standard factory-packaged colours and, on request, in custom colours.
• Formulated as an industrial coating; classified as a flammable liquid (Category 3).

Technical specifications

Chemical nature

• Type: Two-component polyurethane topcoat.
• Chemical nature (mixture): Synthetic resins, organic solvents and pigments.

Physical properties (mixed product)

• Appearance: Liquid.
• Colour: According to product name / colour selection.
• Odour: Characteristic.
• Boiling point: Approx. 120 °C.
• Flash point: 46.5 °C (ISO 13736).
• Upper explosion limit: 10 % (v/v).
• Lower explosion limit: 1 % (v/v).
• Vapour pressure: Approx. 100 hPa at 50 °C.
• Density: 1.2 g/cm³ (20 °C).
• Water solubility: Insoluble.
• Auto-ignition temperature: > 400 °C.
• Viscosity (flow time): > 90 s, DIN 53211, 4 mm cup.

Solid content and coverage

• Volume solids (catalysed, without reduction):
  • Whites: 42 %.
  • Colours: 38 %.
• Coverage values (base + converter, without reducer) at 75 µm (3 mils) DFT:
  • Theoretical, brushing and rolling: 6 m²/l (22.7 m²/gal; 244 sq. ft./gal).
  • Practical, conventional air spray: 3.6 m²/l (13.6 m²/gal; 146 sq. ft./gal).
  • Practical, HVLP air spray: 4.5 m²/l (17 m²/gal; 183 sq. ft./gal).

Recommended substrate preparation

• Substrate must be clean, dry and free from dust, grease, oil and other contamination.
• Recommended primer: ALEXSEAL Finish Primer 442.
• Final sanding of Finish Primer 442: 280–400 grit sand paper.
• Apply ALEXSEAL Premium Topcoat 501 within:
  • 4 days after sanding (inside applications).
  • 2 days after sanding for outside use, to ensure adhesion.

Trade names and packaging

• T…. ALEXSEAL Premium Topcoat 501 (Base Color) – 1 QT & 1 Gal.
• C5051 ALEXSEAL Topcoat Converter Spray – 1 QT & 1 Gal.
• C5012 ALEXSEAL Topcoat Converter Brush – 1 Pt & ½ Gal.
• R5070 ALEXSEAL Topcoat Reducer Fast (spray) – 1 QT & 1 Gal.
• R5050 ALEXSEAL Topcoat Reducer Medium (spray) – 1 QT & 1 Gal.
• R5030 ALEXSEAL Topcoat Reducer Slow (spray) – 1 QT & 1 Gal.
• R5015 ALEXSEAL Topcoat Reducer Brush – 1 QT & 1 Gal.
• A5018 ALEXSEAL 501 Topcoat Roll Additive – 4 ounces.
• A5035 ALEXSEAL Topcoat 501 Accelerator – 4 ounces.

Mix ratios

Spray application

• 1 part by volume T…. ALEXSEAL Premium Topcoat 501 (Base Color).
• 1 part by volume C5051 ALEXSEAL Topcoat Converter Spray.
• 30–37.5 % by volume R… ALEXSEAL Topcoat Reducer (R5070, R5050 or R5030).
• Example: 1 : 1 : 3/4 = 37.5 % reduction.
• Material must be filtered with an appropriate paint filter before application.

Brush/Roll application

• 2 parts by volume T…. ALEXSEAL Premium Topcoat 501 (Base Color).
• 1 part by volume C5012 ALEXSEAL Topcoat Converter Brush.
• 16–33 % by volume R5015 ALEXSEAL Topcoat Reducer Brush.
• Example: 2 : 1 : 1 = 33 % reduction.
• Additional reducer may be added to the pre-mixed paint pot during application to improve flow-out.
• Mixed material must be filtered before application.

Roll-only additive

• A5018 Roll Additive is used to reduce the need to tip off with a brush when applying by roller only.
• Per mixed (catalysed and reduced) 1 quart (1 litre) of Premium Topcoat 501: maximum 1 cap or 10 ml (1/3 oz) A5018 Roll Additive.
• Wait 15 minutes after adding A5018 before adding reducer; then roll onto the properly prepared surface.

Accelerator

• A5035 ALEXSEAL Topcoat 501 Accelerator is used to reduce drying time.
• Per mixed (catalysed and reduced) 2 quarts (2 litres) of Premium Topcoat 501: maximum 1 cap or 10 ml (1/3 oz) A5035 Accelerator.
• Additional accelerator shortens pot life and is not recommended.

Application parameters

• Recommended application viscosities:
  • Zahn #2 Signature cup: approx. 15–17 s.
  • DIN 4 mm cup: approx. 12–16 s.
  • ISO 3 mm cup: approx. 45–55 s.
• Nozzle sizes:
  • Gravity gun: 1.0–1.4 mm (0.039–0.055) – conventional and HVLP.
  • Siphon cup: 1.6 mm (0.063) – conventional and HVLP.
  • Pressure pot fluid nozzle: 1.0–1.3 mm (0.039–0.051) – conventional and HVLP.
  • Airmix equipment: 0.18–0.28 mm (0.007–0.011); inlet pressure 3.0–5.0 bar (42–70 PSI).
• Atomizing pressure: 3.0–5.0 bar (42–60 PSI) – conventional and HVLP.
• Pot pressure: 0.7–1.5 bar (10–20 PSI) – conventional and HVLP.

Film thickness and number of coats

• Application by spraying:
  • Per coat WFT: 50–75 µm (2–3 mils).
  • Tack time between coats: 20–60 minutes.
  • 2-coat system: 30–50 µm (1.5–2 mils) DFT.
  • 3-coat system: 50–70 µm (2–3 mils) DFT.
  • Maximum recommended spray build: 3 coats, total 225 µm (9 mils) WFT or 75 µm (3 mils) DFT.
• Application by brush/rolling:
  • 2–3 coats, 50–75 µm (2–3 mils) WFT per coat.
  • Each coat to dry to tape-dry stage: 12–24 hours.
  • Sand between coats with 320–400 grit.
  • 2-coat system: 30–50 µm (1.5–2 mils) DFT.
  • 3-coat system: 50–70 µm (2–3 mils) DFT.

Pot life and drying (environment 15–30 °C, 40–80 % RH)

• Pot life (approx., without accelerator):
  • 15 °C: 6 h.
  • 20 °C: 6 h.
  • 25 °C: 4 h.
  • 30 °C: 4 h.
• Pot life with A5035 Accelerator:
  • 15 °C: 3 h.
  • 20 °C: 3 h.
  • 25 °C: 2 h.
  • 30 °C: 2 h.
• Dust-free:
  • 15 °C: 90 min.
  • 20 °C: 60 min.
  • 25 °C: 45 min.
  • 30 °C: 30 min.
• Tape dry without accelerator:
  • 15 °C: 36 h.
  • 20 °C: 30 h.
  • 25 °C: 24 h.
  • 30 °C: 18 h.
• Tape dry with A5035 Accelerator:
  • 15 °C: 30 h.
  • 20 °C: 24 h.
  • 25 °C: 18 h.
  • 30 °C: 12 h.
• Fully cured (without accelerator):
  • 15 °C: 21 days.
  • 20 °C: 18 days.
  • 25 °C: 14 days.
  • 30 °C: 10 days.
• Spray recoat with additional Premium Topcoat 501 (after tack up):
  • 15 °C: 90 min (max. 16 h).
  • 20 °C: 60 min (max. 16 h).
  • 25 °C: 45 min (max. 16 h).
  • 30 °C: 30 min (max. 16 h).
• Brush/Roll recoat with additional Premium Topcoat 501 (after tack up):
  • 15 °C: 12 h (max. 24 h).
  • 20 °C: 8 h (max. 24 h).
  • 25 °C: 6 h (max. 24 h).
  • 30 °C: 6 h (max. 24 h).
• Overcoat with another product (sanding required after maximum time): 24 h at 15–30 °C.
• Recommended drying conditions:
  • Minimum temperature during drying: 15 °C (60 °F).
  • Ideal temperature: 25 °C (77 °F).
  • Minimum application conditions: 3 °C (5.4 °F) above dew point.

Classification and hazards (summary)

• Classification (Regulation (EC) No. 1272/2008):
  • Flammable liquids, Category 3 – H226: Flammable liquid and vapour.
  • Long-term (chronic) aquatic hazard, Category 3 – H412: Harmful to aquatic life with long lasting effects.
• Signal word: Warning.
• VOC content (Directive 2010/75/EU, excluding water): 50 %; 604 g/l.

Applications and use cases

• Yacht exteriors: hulls, superstructures and topsides above the waterline where a durable, high-gloss, UV- and salt-resistant finish is required.
• Yacht interiors: decorative high-gloss surfaces in cabins and interior structures, provided they are not in permanently immersed areas.
• Industrial serial painting where a polyurethane, high-gloss, solventborne topcoat with good durability is specified.
• Spray booths and professional workshops using conventional or HVLP spray equipment, or brush/roller application methods.

FAQ

1. Is PREMIUM TOPCOAT 501 suitable for permanent water immersion?

   No. The product is specified for areas not subject to permanent water immersion.

2. What primer is recommended before applying this topcoat?

   ALEXSEAL Finish Primer 442 is recommended for optimum performance and adhesion. Final sanding should be with 280–400 grit sand paper.

3. Can I apply the product by brush or roller?

   Yes. It can be applied by brush and roller using the specified brush mix ratio and R5015 reducer. A5018 Roll Additive can be used, including for roll-only application.

4. How long is the pot life after mixing?

   Approximate pot life is 6 hours at 15–20 °C and 4 hours at 25–30 °C. With A5035 Accelerator, pot life is reduced to 3 hours at 15–20 °C and 2 hours at 25–30 °C.

5. When can I recoat with additional PREMIUM TOPCOAT 501 by spray?

   After tack up, typical minimum recoat times are 90 minutes at 15 °C, 60 minutes at 20 °C, 45 minutes at 25 °C and 30 minutes at 30 °C, with a maximum of 16 hours.

6. What level of gloss does this product provide?

   The product is described as a high-gloss wet-look topcoat with excellent gloss and colour stability. Consultar ficha técnica del fabricante.

7. Which colours are available?

   It is available in standard factory-packaged colours and, on request, custom colours. Specific colour codes are referenced in the colour card and product overview.

8. Is this product flammable?

   Yes. It is classified as a flammable liquid, Category 3 (H226: Flammable liquid and vapour). Keep away from heat, sparks, open flames and hot surfaces.

9. Is PREMIUM TOPCOAT 501 harmful to the environment?

   It is classified as harmful to aquatic life with long lasting effects (H412). Avoid release to the environment and prevent product from entering drains, lakes or rivers.

10. Can I find detailed information about compatibility with other systems?

    Consultar ficha técnica del fabricante.

Section 14 – Transport information

• UN number: UN 1263.
• UN proper shipping name (ADR / IMDG / IATA): PAINT.
• Transport hazard class:
  • ADR: Class 3.
  • IMDG: Class 3.
  • IATA: Class 3.
• Packing group: III (ADR / IMDG / IATA).
• ADR details:
  • Classification code: F1.
  • Hazard identification number: 30.
  • Labels: 3.
  • Tunnel restriction code: (D/E).
  • Special provision: 640E.
• IMDG details:
  • Labels: 3.
  • EmS code: F-E, S-E.
  • Marine pollutant: No.
• IATA details:
  • Packing instruction (cargo aircraft): 366.
  • Packing instruction (passenger aircraft): 355.
  • Labels: Flammable Liquids.
• Environmental hazards during transport:
  • ADR: Not classified as environmentally hazardous.
  • IMDG: Not a marine pollutant.
• Special precautions for users:
  • Within the user’s premises, always transport in closed, upright and secure containers.
  • Ensure that personnel transporting the product are aware of procedures in case of incident or spillage.
  • Receptacles with less than 450 litres capacity are not subject to ADR (ADR 2.2.3.1.5).
  • Receptacles with less than 30 litres capacity are not subject to IMDG chapters 4.1, 5.2 and 6.1 (IMDG 2.3.2.5).
• Transport in bulk according to MARPOL Annex II and the IBC Code: Not applicable for product as supplied.

Section 8 – Individual protection measures

Engineering controls

• Ensure adequate ventilation, preferably by local exhaust ventilation and good general extraction.
• If ventilation does not keep aerosol and solvent vapour concentrations below occupational exposure limits, use suitable respiratory protection.

Personal protective equipment

• Eye protection: Wear safety goggles to protect against solvent splashes.
• Hand protection:
  • Use chemical-resistant protective gloves tested to EN 374.
  • Recommended materials for short-term contact (splash protection): nitrile rubber or neoprene.
  • Minimum material thickness: > 0.4 mm.
  • Breakthrough time: > 480 minutes.
  • Check suitability for the specific workplace (mechanical resistance, product compatibility, antistatic properties).
  • Replace gloves immediately if damaged or showing signs of wear.
  • Preventive skin protection (skin protection cream) is recommended; wash contaminated skin immediately.
• Skin and body protection:
  • Wear antistatic clothing made of natural fibres (e.g. cotton) or high-temperature-resistant synthetic fibres.
  • Wash all body parts after contact with the product.
• Respiratory protection:
  • If exposure levels exceed occupational limits, use appropriate certified respirators.
  • Use at least a half-mask with cartridge or air-fed system.
  • Dry grinding, torch cutting or welding of coated surfaces can produce hazardous dust and vapours; use wet methods where possible and/or effective local exhaust and suitable respiratory equipment.

General protective measures and handling advice

• Do not eat, drink or smoke during use.
• Avoid contact with skin, eyes and clothing.
• Avoid inhalation of sanding dust, particulates and spray mist.
• When working inside a spray booth, operators should wear air-fed respiratory protection until solvent vapour and particulate levels are below exposure limits.
• Keep away from heat, sparks, open flames and hot surfaces; observe all regulations for handling flammable liquids.