High-Performance One-Component Polyurethane Adhesive for Fire-Rated Hollow Metal Doors
Product Overview
This One-Component (1K) Moisture-Curing Polyurethane Adhesive is an industrial-grade bonding solution engineered specifically for the door manufacturing industry. It reacts and cures by absorbing ambient moisture from the air and the bonding substrate surface. For faster processing cycles, a fine water-mist spray can be applied directly to the glue line to accelerate curing.
Once fully cured, the adhesive forms an infusible, insoluble thermosetting bond line that delivers superior mechanical strength, thermal stability, and long-term durability. It is ideal for cross-bonding galvanized/cold-rolled steel, stainless steel, wood, and various fire-rated thermal insulation cores.
Key Technical Specifications
| Parameter | Specification |
| Appearance | Brown viscous liquid |
| Specific Gravity | 1.15 ± 0.05 g/cm³ |
| Viscosity | 0.2 – 0.3 Pa·s (Customizable upon request) |
| Solid Content | ≥ 90% |
| Coating Spread Rate | 140 – 180 g/m² |
| Tack-Free Time (Surface Dry) | ≤ 1 hour |
| Full Curing Time | 4 – 8 hours (Adjustable to production line speed) |
| Thinner / Diluent | Ethyl Acetate |
| Bonding Strength (Metal to Metal) | ≥ 10 MPa |
| Bonding Strength (Metal to Non-Metal) | Substrate failure (Non-metal destruction) |
Core Performance & Engineering Advantages
- High Cohesive & Shear Strength: Achieves ≥ 10 MPa shear strength on metal-to-metal joints. On porous fireproof cores, the bond exceeds the material's internal cohesive strength, resulting in substrate failure before bond delamination.
- Thermosetting Durability: The cured polymer matrix is non-melting and insoluble, ensuring the door leaf maintains structural integrity under extreme heat, vibration, and thermal expansion.
- Efficient Application: High solids formulation (≥ 90%) with low solvent emissions. The low-to-medium viscosity (0.2–0.3 Pa·s) allows for effortless roll-coating, notched trowel spreading, or automated line application.
- Controlled Curing Adaptability: Standard curing cycle runs between 4 to 8 hours, with tack-free time under 1 hour. Curing speed can be tailored to match hot-press or cold-press production workflows.
Suitable Substrates & Applications
- Metal Skins: Cold-rolled steel, galvanized steel sheets, stainless steel, and aluminum plates.
- Fire-Rated Cores: Rockwool / mineral wool slabs, ceramic fiber boards, perlite fire door cores, and magnesium oxide (MGO) boards.
- Structural & Insulation Panels: Fire-retardant paper honeycomb, expanded polystyrene (EPS), extruded polystyrene (XPS), polyurethane (PU/PIR) foam, and solid wood / MDF.
Processing & Operation Guidelines
- Surface Preparation: Ensure metal sheets are clean, dry, and degreased of anti-rust oils, mill scale, and dust.
- Glue Spreading: Apply uniformly at a rate of 140–180 g/m² using a roller coater, scraper, or automated glue applicator.
- Moisture Acceleration (Optional): In dry climates or low-humidity workshops (< 50% RH), atomize a light water mist (approx. 5–10% of glue weight) over the glue film to speed up curing.
- Assembly & Pressing: Assemble the sandwich structure within the open time and apply uniform pressure (0.2–0.4 MPa) in a cold or heated press until the core achieves handling strength.
