PPG SigmaCover 435 – High-Build MIO Epoxy Buildcoat for Steel & Concrete

PPG SigmaCover 435 is a two-component, high-build, micaceous iron oxide (MIO) pigmented epoxy coating designed for long-lasting protection of steel and concrete structures in both atmospheric land and marine environments. Delivering excellent durability, flexibility and water resistance, it performs reliably even in demanding conditions-including cold temperatures down to -10°C and high humidity up to 95% during application and curing.

Formulated for both new construction and maintenance, SigmaCover 435 offers strong adhesion to a wide range of aged coatings and can be easily recoated with most two-component or conventional systems, even after long weathering periods. Its eggshell finish and ease of application via airless spray or brush make it a versatile and dependable choice.

Key Features:

• Two-component, high-build epoxy with MIO pigmentation

• Suitable for steel & concrete in land and marine environments

• Cures at low temperatures: down to -10°C (14°F)

• Tolerates up to 95% relative humidity during application

• Excellent adhesion to aged alkyd, chlorinated rubber and epoxy coatings

• Recoatable with most two-component and conventional systems

• Tough, flexible and resistant to water and mild chemical splash

• Eggshell finish with easy airless spray or brush application

• No induction time – 5-hour pot life

• Fast curing: Fully cured in 4 days at 20°C

Surface Preparation

Substrate conditions
• Steel; blast cleaned to ISO-Sa2½, blasting profile 40 – 70 µm (1.6 – 2.8 mils)
• Steel with zinc silicate shop primer; pretreated according to ISO Sa1 (SSPC SP7) or hand/power tool cleaned to minimum ISO St2 (SSPC SP2)
• Previous coat must be sound, dry and free from any contamination
Substrate temperature
• Substrate temperature during application and curing down to -10°C (14°F) is acceptable; provided the substrate is free from ice and dry
• Substrate temperature during application and curing should be at least 3°C (5°F) above dew point

Technical Data

Pot life
5 hours at 20°C (68°F)

Spreading rate and film thickness
DFT Theoretical spreading rate
75 µm (3.0 mils) 8.4 m²/l (337 ft²/US gal)
100 µm (4.0 mils) 6.3 m²/l (253 ft²/US gal)
150 µm (6.0 mils) 4.2 m²/l (168 ft²/US gal)

Directions for Use

Mixing ratio by volume: base to hardener 82:18 (4.56:1)
• The temperature of the mixed base and hardener should be above 10°C (50°F), otherwise extra thinner may be required to obtain application viscosity
• Thinner should be added after mixing the components
• Adding too much thinner results in reduced sag resistance

Air spray
Recommended thinner
THINNER 91-92
Volume of thinner
10 - 15%, depending on required thickness and application conditions
Nozzle orifice
2.0 – 3.0 mm (approx. 0.079 – 0.110 in)
Nozzle pressure
0.3 - 0.4 MPa (approx. 3 - 4 bar; 44 - 58 p.s.i.)
Airless spray
Recommended thinner
THINNER 91-92
Volume of thinner
5 - 10%, depending on required thickness and application conditions
Nozzle orifice
Approx. 0.48 – 0.58 mm (0.019 – 0.023 in)
Nozzle pressure
15.0 MPa (approx. 150 bar; 2176 p.s.i.)
Brush/roller
Recommended thinner
THINNER 91-92
Volume of thinner
0 – 5%
Cleaning solvent
• THINNER 90-53

Data Sheets

SigmaCover 435 TDS

SigmaCover 435 Base MSDS

SigmaCover 435 Hardener MSDS