Guangzhou Feisi Launches FS7380 Water-Based Epoxy Composite Adhesive, Solving Mass Production Challenges for Interlayer Bonding of Amorphous Ribbons
Single-component, water-based eco-friendly system that streamlines the entire process from coating to drying to thermal curing, providing non-crystalline core manufacturers with a low-loss, high-strength, and green-compliant interlayer insulation solution.
1. Industry Pain Points: Three Major Hurdles Limiting Mass Production of Amorphous Iron Cores
Against the backdrop of surging demand for new energy PV inverters, energy storage inductors, high-frequency amorphous motors, and energy-efficient distribution transformers, amorphous cores have become the industry's mainstream solution thanks to their ultra-low core loss. However, most manufacturers remain constrained by forming and processing challenges, facing severe difficulties in mass production yield rates and cost control:
Challenge 1: Difficult Material Processing Amorphous ribbons are only 20~30μm thick, with high hardness, poor plasticity, and extreme brittleness. Cutting, stamping, and winding processes frequently cause edge chipping, delamination, fragmentation, and strand breakage, resulting in low yield rates. High wear on stamping dies drives up processing costs.
Challenge 2: Poor structural stability of finished products. Simple laminated sheet structures are loose, causing the strips to easily shift and disintegrate during assembly or long-term vibration operation. This leads to core performance failure or total scrap, resulting in significant production cost losses.
Challenge 3: Escalating Environmental Compliance Pressure. Traditional solvent-based adhesives emit high VOCs and cause strong odors in the workshop, requiring expensive exhaust gas treatment equipment. Export orders face barriers from RoHS/REACH environmental testing, hindering market expansion for internal and external sales of iron cores.
Key Takeaway: High-efficiency composite molding technology for amorphous strips—simultaneously addressing reduced brittleness, improved lamination efficiency, and reliable interlayer insulation—is a critical need for amorphous core manufacturers. Guangzhou Feisi has developed FS7380 water-based epoxy composite adhesive specifically for amorphous strip applications. Based on a single-component waterborne epoxy emulsion system, it streamlines the entire process from coating to drying to thermal curing, solving both electromagnetic performance and environmental compliance challenges in one solution.
2. FS7380 Core Positioning: An eco-friendly insulating adhesive specifically designed for interlayer lamination of amorphous alloy strips
FS7380 is a single-component, ready-to-use coating formulated with specialty waterborne epoxy resin, dedicated hardener, functional additives, and deionized water. It requires no on-site mixing, features simple operation, and is fully compatible with automated roller coating production lines.
Pure formulation: Free of inorganic salts and fillers. Thin, lightweight coating that does not interfere with magnetic permeability or performance.
Eco-Compliance: Low odor, low VOC. Fully cured coating meets EU RoHS and REACH regulations; suitable for both domestic and international cores.
Process-friendly: Features a self-adhesive layer after drying for stable multi-layer alignment. High-temperature hot pressing significantly enhances core strength and isolates interlayer corrosion.
3. Four Core Advantages: Balancing Low Loss with Eco-Friendly Mass Production
High insulation with low eddy current losses reduces noise and improves energy efficiency. After curing, the coating surface resistivity is ≥2000 Ω·mm²/lam., forming a uniform insulating barrier that effectively blocks interlaminar eddy currents. This significantly lowers no-load losses in iron cores and reduces operating noise in motors and transformers, ensuring stable long-term performance for high-frequency new energy equipment.
Full water-based eco-friendly system significantly reduces environmental compliance costs. Using water as the dilution medium, VOC content is minimal—no irritating odors in the workshop. Equipment cleans with tap water alone; no specialized solvents needed. No expensive exhaust treatment required—pass environmental reviews easily and export without any compliance hurdles.
Initial tack stability + high peel strength reduces delamination. Self-adhesive after coating and curing, minimizing slippage during stacking; post-thermal lamination peel force ≥ 0.15 N/mm ensures robust core bonding, preventing cracks or delamination during handling, assembly, and long-term operation, effectively boosting mass production yield.
Dual-Temperature Resistance: Engineered for High-Temp Curing and Harsh Conditions Coating achieves dual certification: Bond strength meets Class F (155°C); Surface resistance meets Class H (180°C). Perfectly compatible with industry-standard 200~250°C curing processes, maintaining stable insulation performance under prolonged high-temperature operation.
4. Full Set of Standardized Performance Parameters (Internationally Certified Testing)
Base Specifications for Paint Base Liquid (at 25°C Standard Environment)
Appearance: Uniform milky-white liquid (no separation, no sediment)
Solid content: 30% ± 2% (water-based single-component system)
Viscosity (25°C): Adjustable range (tailored for roller coating process requirements)
pH: 7.0 ~ 9.0 (slightly alkaline, non-corrosive to substrate)
Coating performance after drying (wet film 2.0μm, double-sided application)
Appearance: Colorless and transparent
Dry film thickness: 1.0 μm
Coating density: 1.2 g/cm³
Surface resistance: >2000 Ω·mm²/lam.
Peel Strength: ≥0.15 N/mm
Key Coating Performance Metrics After High-Temperature Curing
Appearance: Colorless transparent thin layer
Interlayer insulation resistance: ≥2000 Ω·mm²/lam.
Temperature Rating (Bond Strength): Class F (155°C)
Temperature Rating (Surface Resistance): H (180°C)
5. Standardize implementation processes to support roller coating across the entire range of light rollers and grooved rollers.
FS7380 Complete Production Process: Four Stages, Standardized Parameters Ready for Automated Manufacturing Lines
Step 1: Coating. Apply a wet film thickness of 3.06 μm for single-sided roller coating, or a total wet film thickness of 2.03 μm for double-sided roller coating. Slot-die roller processing uses deionized water for on-site dilution; the dilution ratio is determined through on-site trials based on roller groove dimensions.
Step 2: Dry and Dehydrate – Online drying removes moisture to form a tacky adhesive layer.
Step 3: Multi-layer Lamination – Stack and align the strips, then pre-form.
Step 4: High-temperature curing at 200~250°C under heat pressing, significantly increasing core strength.
[Important Notice] FS7380 contains no inorganic fillers and is not suitable for bluing or annealing heat treatment processes. Before selection, contact the Guangzhou Feisi technical team to verify application suitability and prevent misuse.
6. Production Line Usage and Storage & Transportation Best Practices
Device and Operation Guidelines:
Equipment Materials: The storage tank, circulation pipes, and coating rollers are all made of stainless steel to prevent rust contamination of the paint and water stain defects.
Substrate Pre-treatment: Keep the amorphous ribbon clean and dry before coating, and control the surface temperature to <40°C.
Paint Application: Apply at ambient temperatures between 15 and 25°C. Stir thoroughly before use. When switching to a different paint, thoroughly clean the entire coating unit with demineralized water.
Equipment Cleaning: If the coating is not fully cured, flush the lines with water. After opening the cover, seal the circulation tank and clean the equipment immediately after shutdown. Note: Once the coating hardens completely, it no longer dissolves in water and can easily clog the lines!
Packaging and Storage & Transportation:
Packaging: 200kg stainless steel drums, 1000kg IBC tanks; custom options available
Storage Conditions: 0~30°C in a dry, ventilated indoor area. Keep away from light, heat sources, and open flames.
After opening: Use within 1 months. Seal the lid tightly after each use.
Shelf life: 4-6 months when stored sealed at 25°C
7. Guangzhou Feisi: One-stop material and process technology support services
Guangzhou Feisi Materials Technology Co., Ltd. specializes in the R&D and production of water-based epoxy insulating coatings for magnetic materials. With its own standardized material laboratory and automated production lines, we provide customized bonding and insulation coating solutions for amorphous and nanocrystalline core manufacturers.
End-to-end support:
Free sample testing — matches amorphous ribbons of different grades with various roller coating equipment to validate process compatibility
On-site engineer commissioning — Optimize coating and curing process parameters, reduce trial production losses, and shorten mass production ramp-up cycles.
Complete technical documentation—including the technical specification and third-party test reports—provided together to meet diverse customer needs.
Bulk supply with stable inventory — ample stock, short lead times to ensure uninterrupted production lines