Benjamin Moore | Max Block™ Water-Based Stain Blocking Primer (SB-5000)

Max Block™ Water-Based Stain Blocking Primer (SB-5000) is a next-generation, high-performance primer engineered to deliver superior stain blocking compared to conventional water-based primers. Formulated as a low-VOC alternative to alkyd stain blockers, it seals and locks in tannin bleed, tough household stains, and odor-causing contaminants while providing excellent adhesion, hiding, and uniform topcoat holdout.

• Advanced water-based stain blocking technology.
• Specifically formulated to seal tannins and prevent bleed-through.
• Blocks common stains and odors from smoke, water, crayon, markers, grease, and lipstick.
• Fast drying — ready to topcoat in about 1 hour.
• Mildew-resistant coating for long-term durability.
• Excellent adhesion, including to glossy surfaces.

• Surfaces must be clean, dry, and sound.
• Remove dirt, grease, wax, soap residue, mildew, and loose paint.
• Dull glossy surfaces for best adhesion.
• New plaster or masonry must cure for 30 days before priming.
• Spot prime repaired areas before and after patching.

• Stir thoroughly before use.
• Apply by brush, roller, or airless spray.
• Apply at full strength — do not thin or tint.
• Two coats may be required for severe stains.
• Topcoat with latex or oil-alkyd finishes, preferably the same day.

• Is Max Block oil-based?
  No. It is a water-based acrylic primer with advanced stain-blocking performance.
• Can it replace an alkyd stain-blocking primer?
  Yes. It provides a lower-VOC alternative to traditional alkyd stain blockers.
• Does it block tannin bleed?
  Yes. It is specifically formulated to lock in tannins and prevent bleed-through.
• How soon can I paint over it?
  You can apply a finish coat in approximately 1 hour under normal conditions.