HUMISEAL HumiSeal 1B31S (5-LTR-CAN)

HumiSeal® 1B31S Acrylic Conformal Coating

Overview

HumiSeal® 1B31S is a fast-drying, single-component acrylic conformal coating designed to provide printed circuit assemblies with excellent moisture protection, environmental resistance, and improved adhesion. The coating offers outstanding flexibility, UV fluorescence for inspection visibility, and easy repairability, making it suitable for aerospace, electronics, and high-reliability applications.

Key Technical Specs

• Product Type: Single-component acrylic conformal coating
• Appearance: Clear coating with UV fluorescent properties
• Density: 0.91 ± 0.02 g/cm³
• Solids Content: 35 ± 3% by weight
• Viscosity: 200 ± 15 centipoise
• VOC Content: 592 g/L
• Recommended Coating Thickness: 25-75 microns
• Drying Time to Handle: Approximately 10 minutes
• Full Property Development: 7 days
• Shelf Life: 24 months at room temperature

Approvals & Specifications

• MIL-I-46058C qualified
• IPC-CC-830 compliant
• RoHS Directive 2002/95/EC compliant
• Thermal shock tested to MIL-I-46058C
• Fungus resistance tested to ASTM G21

Typical Applications

• Protection of printed circuit assemblies (PCAs)
• Aerospace electronic equipment
• High-reliability electronic systems
• Electronic assemblies requiring moisture and environmental protection
• Applications requiring easy inspection and repair

Performance Features & Benefits

• Excellent moisture and environmental protection
• Improved adhesion to electronic substrates
• Highly flexible coating suitable for thermal cycling
• UV fluorescent for fast inspection and quality control
• Easy repairability during maintenance operations
• Self-extinguishing flammability performance
• High dielectric strength and insulation resistance

Thermal & Mechanical Properties

• Thermal Shock: 50 cycles from -65°C to 125°C
• Glass Transition Temperature (Tg): 14°C
• Coefficient of Thermal Expansion:
• 170 ppm/°C below Tg
• 340 ppm/°C above Tg
• DMA Modulus:
• 2000 MPa at -40°C
• 1050 MPa at 20°C
• 8.5 MPa at 60°C

Application Methods

• Dipping: Use HumiSeal® Thinner 503 where viscosity adjustment is required. Recommended withdrawal rate: 5-15 cm/min.
• Spraying: Use HumiSeal® Thinner 521 to achieve a uniform, pinhole-free coating. Typical mixing ratio: 1:1 by volume.
• Brushing: Can be applied with small additions of HumiSeal® Thinner 503.

Surface Preparation Requirements

• Substrate must be completely clean and dry before application
• Remove moisture, dirt, grease, wax, flux residues, and contaminants
• Contamination beneath the coating may result in assembly failures

Curing & Drying

• Dry to handle: Approximately 10 minutes
• Recommended cure: 24 hours at room temperature
• Accelerated cure: 30 minutes at 76°C
• Optimum properties achieved after 7 days

Compatibility & Safety Notes

• Store in tightly closed containers away from excessive heat or cold
• Recommended storage temperature: 0-35°C
• Allow product to equilibrate for 24 hours at 18-32°C before use
• Solvents are flammable-keep away from flames and sparks
• Use only in well-ventilated areas
• Avoid skin and eye contact
• Consult SDS before use

Packaging & Procurement

• Available through HumiSeal distribution channels
• Recommended thinners:
• HumiSeal® Thinner 503 (dipping and brushing)
• HumiSeal® Thinner 521 (spraying)
• Recommended stripper: HumiSeal® Stripper 1080

Why This Product is Chosen for Aerospace / Electronics MRO

• Provides reliable environmental protection for sensitive electronics
• Qualified to recognised military and industry standards
• UV traceability improves inspection efficiency
• Flexible coating withstands thermal cycling and vibration environments
• Repairable formulation supports maintenance operations

Practical Suggestions for Your Team (MRO Mindset)

• Ensure complete PCB cleanliness before coating application
• Control viscosity during dipping and spraying operations
• Apply within recommended thickness range to avoid defects
• Use UV inspection after curing to confirm coating coverage
• Allow full cure time before electrical service or environmental exposure

Manufacturer / Aviation Spec Codes

• Product Name: HumiSeal® 1B31S
• Product Type: Acrylic conformal coating
• Specification: MIL-I-46058C / IPC-CC-830
• Application: Electronic assembly protection coating