PPG SigmaCover 1500 is a two-component, surface-tolerant, solvent-free, polyamine-cured epoxy primer/buildcoat for long-term protection of steel structures, with excellent corrosion resistance. Compatible with various aged coatings, like aged alkyd, epoxy and polyurethane, SigmaCover 1500 can be used at temperatures above 5°C (41°F) and reduces explosion risk and fire hazard in confined spaces.

Features & Benefits

• General-purpose primer/buildcoat for long-term protection of steel structures
• Two component
• Solvent-free
• Polyamine-cured epoxy
• Excellent corrosion resistance
• Compatible with various aged coatings, like aged alkyd, epoxy and polyurethane
• Reduces explosion risk and fire hazard in confined spaces
• Good flow and wetting properties
• Can be used at temperatures above 5°C (41°F)
• Can be applied by spray or roller
• Touch dry after 12 hours
• Can be overcoated after 24 hours
• See below for more information on surface preparation, application details and curing times

Product Data

Two-component, surface-tolerant, solvent-free, polyamine-cured epoxy primer/coating.

Notes:

• Refer below for more details on spreading rate and film thickness, overcoating intervals and curing times

Surface Preparation

Recommended Substrate Conditions and Temperatures

Substrate conditions

• Steel; blast cleaned to ISO-Sa2½ for excellent corrosion protection
• Steel; blast cleaned to ISO-Sa2 or power tool cleaned to ISO-St2 for good corrosion protection
• Steel with approved zinc silicate shop primer; sweep blasted to SPSS-Ss or power tool cleaned to SPSS-Pt3
• Stainless steel; degreased and blast cleaned to roughness of 40 – 70 µm (1.5 – 2.8 mils)
• Existing sound epoxy coating, polyurethane and most sound alkyd coating systems; sufficiently roughened dry and cleaned

Substrate Temperature & Application Conditions

• Substrate temperature during application and curing should be above 5°C (41°F)
• Substrate temperature during application and curing should be at least 3°C (5°F) above dew point
• Relative humidity during application and curing should not exceed 80%

Application

Instructions for Use

Mixing ratio by volume: base to hardener 80:20 (4:1)

• For airless application, the temperature of base and hardener should be at least 20°C (68°F)
• Lower temperatures possible for roller application
• No thinner should be added

Induction Time

None.

Airless Spray

• Heavy-duty, single-feed airless spray equipment preferably 60:1 pump ratio and suitable high-pressure hoses
• In-line heating or insulated hoses may be necessary to avoid cooling down of paint in hoses at low air temperature

Recommended thinner

• No thinner should be added

Nozzle orifice

• Approx. 0.43 mm (0.017 in)

Nozzle pressure

• 15.0 MPa (approx. 150 bar; 2176 p.s.i.)

Brush/roller

• Roller: nylon suitable for two-component epoxy with hair length 8 mm (0.315 in)
• Brush: for stripe coating and spot repair only

Recommended thinner

• No thinner should be added

Cleaning Solvent

• Thinner 90-53 or 90-83.

Notes:

• Paint inside the spraying equipment must be removed before the pot life has been expired
• All application equipment must be cleaned immediately after use

Spreading Rate and Film Thickness

Note:

• Maximum DFT when brushing: 100 µm (4.0 mils)

Measuring wet film thickness

• A difference is often obtained between the measured apparent WFT and the real applied WFT. This is due to the thixotropy and the surface tension of the paint, which retards the release of air, trapped in the paint film for some time

Measuring dry film thickness

• Because of low initial hardness the DFT cannot be measured for some days (depending on ambient temperature) after application, due to the penetration of the measuring device into the paint film
• The DFT should be measured using a calibration foil of known thickness placed in between the coating and the measuring device

Overcoating interval for DFT up to 125 µm (5.0 mils)

Notes:

• Surface should be dry and free from any contamination
• Best intercoat adhesion occurs when the subsequent coat is applied before the fully cured stage is reached
• If this time is exceeded the surface has to be roughened

Curing time for DFT up to 125 µm (5.0 mils)

Notes:

• Adequate ventilation must be maintained during application and curing (please refer to information sheets information sheet 1433 and
• Directives for Ventilation Practice (information sheet 1434)

Pot Life (at application viscosity)

Note:

• Due to exothermic reaction, temperature during and after mixing may increase

Safety Precautions

• For paint and recommended thinners, see information sheets information sheet 1430, information sheet 1431 and the relevant Material Safety Data Sheets in the attachments section above
• Although this is a solvent-free paint, care should be taken to avoid inhalation of spray mist, as well as contact between the wet paint and exposed skin or eyes
• Spray mist is not harmless, a fresh air mask and gloves should be used during spraying
• Ventilation should be provided in confined spaces to maintain good visibility

References

• Explanation to product data sheets (information sheet 1411)
• Safety Indicators (information sheet 1430)
• Safety in Confined Space and Health Safety, Explosion Hazard - Toxic Hazard (information sheet 1431)
• Safe Working in Confined Spaces (information sheet 1433)
• Directives for Ventilation Practice (information sheet 1434)