Henkel LOCTITE SF 7400 (20-Gram-Btl)

LOCTITE® SF 7400™ Marking Ink

Overview

LOCTITE® SF 7400™ is a solvent-based red marking ink designed for tamper-proofing, inspection marking, and adjustment-point verification on electronic and industrial equipment. The fast-drying formulation creates a highly visible pigmented film that adheres strongly to a wide variety of metals and polymers. It is commonly used to indicate that components have been calibrated, adjusted, inspected, tested, or approved, while also providing visual evidence of unauthorized movement or tampering.

Key Technical Characteristics

• Product Type: Tamper-proofing and inspection marking ink
• Technology: Solvent-based
• Chemical Type: Pigmented organic polymer
• Appearance: Dark red liquid
• Cure Mechanism: Solvent evaporation
• Viscosity: 1,030 mPa�s (cP)
• Solids Content: 22.5%
• Tack-Free Time (100 ?m film): Approximately 5 minutes
• Dry Time (100 ?m film): 5-7 hours
• Color After Drying: Highly visible red film

Core Performance Benefits

• Provides clear visual indication of inspection or calibration status
• Offers tamper-evidence for adjustment points and assemblies
• Fast tack-free drying improves production efficiency
• Excellent adhesion to metals and polymer surfaces
• Highly visible red color improves inspection reliability
• Simple application without specialized equipment
• Suitable for quality control and manufacturing processes
• Can be removed using appropriate solvents when required

Typical Applications

• Electronic equipment inspection marking
• Calibration verification markings
• Tamper-proofing adjustment screws and controls
• Quality assurance inspection programs
• Manufacturing process verification
• Assembly completion identification
• Maintenance inspection tracking
• Component testing and certification marking

Material Engineering & Design Features

LOCTITE® SF 7400™ is formulated as a pigmented organic polymer coating that dries through solvent evaporation. Once dried, the material forms a durable, highly visible film that bonds effectively to a wide range of engineering materials.

The coating provides:

• Strong adhesion to metals
• Good adhesion to polymer materials
• High visibility for inspection personnel
• Fast surface drying characteristics
• Durable tamper-evident markings

Unlike permanent coatings, the dried film can be removed when necessary using appropriate solvents and mechanical cleaning methods.

Installation & Handling

• Shake container thoroughly before use to redisperse pigments
• Allow trapped air bubbles to dissipate before application
• Apply directly to the desired surface or adjustment point
• Thin films (~100 ?m) become tack-free in approximately 5 minutes
• Allow approximately 6 hours for complete drying
• Remove uncured material using solvents such as:
  • MEK (Methyl Ethyl Ketone)
  • Butyl Acetate
• Fully cured films may require mechanical removal followed by solvent cleaning

Environmental & Compliance Notes

• Flammable solvent-based product
• Store in original unopened containers
• Recommended storage temperature: 8°C to 21°C
• Avoid storage below 8°C or above 28°C
• Keep away from oxidizing agents and combustible materials
• Not recommended for pure oxygen or oxygen-enriched systems
• Consult the Safety Data Sheet (SDS) before use

Key Advantages

• Provides clear visual confirmation of adjustment, calibration, or inspection status
• Fast-drying formulation supports production efficiency
• Excellent adhesion to a wide range of materials
• Creates highly visible tamper-evident markings
• Simple application and removal procedures
• Suitable for electronics, industrial equipment, and quality control programs
• Reliable long-term marking performance
• Widely used for inspection verification and tamper-proofing applications