The KF-MIO500 epoxy MIO intermediate coat is a classic mid-coat for heavy-duty anticorrosive coating systems. Mica iron oxide (Micaceous Iron Oxide, MIO) is the principal anti-corrosive pigment: its platelet crystal structure aligns in parallel within the film, creating a "tortuous-path" effect that greatly lengthens the permeation path of corrosive media such as water, oxygen and chloride ions. Combined with the excellent adhesion and mechanical strength of the epoxy resin, it multiplies the anticorrosive service life of the whole system. It is the standard intermediate coat between an epoxy zinc-rich primer and a polyurethane/fluorocarbon topcoat.
TDS Technical Data Sheet – Epoxy Micaceous Iron Oxide Intermediate Coating KF-MIO500
Technical Data Sheet · Epoxy MIO intermediate coat · KF-MIO500
1. Product Description
2. Typical Applications
Tie-coat compatible with the epoxy zinc-rich primer KF-ZR800 and polyurethane or fluoropolymer topcoats in C4/C5 corrosivity environments. Standard midcoat for heavy-duty systems on bridge steelwork, petrochemical plant, offshore platforms, storage tanks and ship superstructures.
3. Technical Parameters
| Product type | Two-component solvent-borne epoxy intermediate coat |
|---|---|
| Color | Iron-red / gray |
| Gloss | Matt (<20 GU) |
| Volume solids | 55±3% |
| Recommended DFT | 80-150 μm/coat |
| Theoretical spreading rate | 3.7-6.9 m²/L |
| Mixing ratio | A:B = 5:1 (by weight) |
| Pot life | 6h(20°C) |
| Surface dry time (23°C) | ≤2h(23°C) |
| Hard dry time (23°C) | ≤24h(23°C) |
| Min. overcoat interval | 6 h (23°C); up to 7 days at most |
| Full cure | 7 days (23°C) |
| Application temperature | 5-40°C |
| Relative humidity | <85% |
| Flash point (closed cup) | Approx. 28°C |
| Density (mixed) | Approx. 1.8 kg/L |
| VOC content | <400 g/L |
| Adhesion | Grade 0–1 |
| Packaging Specs | 20 L drum |
| Shelf Life | 12 months |
| Salt spray resistance | ≥300 h (with primer) |
| Water vapour transmission rate | ≤50 g/m²·d |
| Standard | ISO 12944-5 / GB/T 25263 |
| Product type | Two-component epoxy micaceous iron oxide (MIO) midcoat |
| Color | Grey / iron grey (natural MIO tone) |
4. Application Guide
Surface preparation
Thoroughly clean the substrate surface to remove oil and rust. Abrasive-blast steel to Sa2.5 (ISO 8501-1) with 40-75μm surface profile. Concrete substrate moisture content must be below 6%, grind to remove laitance. For old coatings, remove loose areas and roughen the surface.
Mixing / compounding
According to the mix ratio indicated on the product label, add the hardener (component B) slowly to the base (component A) and mechanically stir for 3-5 minutes until uniform. Let stand to mature for 10-15 minutes before use. Use up within the specified pot life after mixing.
Application method
Recommended air spray (gun orifice 1.5-2.0 mm, pressure 0.4-0.6 MPa) or airless spray (nozzle 0.38-0.53 mm, pressure 15-25 MPa). Small areas may be brushed or rolled. Keep each coat dry film thickness within the specified range.
Curing conditions
Self-cures at ambient temperature (23°C) provided relative humidity meets requirements. Do not apply under low temperature (<5°C) or high humidity (>85%). Conduct performance testing only after full cure.
5. Packaging & Storage
| Packaging Specs | 20 L drum |
|---|---|
| Storage Conditions | Store at 5–35°C in a cool, dry, ventilated place away from ignition and heat sources; keep container sealed. |
| Shelf Life | 12 months |
| Transport | Transport as non-hazardous goods. In summer, ship in early morning or evening; avoid sun exposure. |
6. Health & Safety Notes
⚠️ Important safety notice
Read and understand the product's MSDS (Material Safety Data Sheet) carefully before using this product.
- Proper personal protective equipment (gloves, goggles, protective suit) must be worn during application
- Ensure the work area is well ventilated
- Keep away from fire and heat sources
- Avoid inhaling vapours and mist
- Avoid contact with skin and eyes
- If you feel unwell, stop work immediately and seek medical advice
Disclaimer
The data in this TDS are typical values and do not constitute product specifications. Actual product performance may vary depending on application conditions, substrate condition and environmental factors. Users are advised to conduct small-scale sample tests before bulk use to confirm product suitability.
Kexin New Materials continuously improves its products and reserves the right to modify technical parameters without prior notice. For the latest version please visit www.psste.com/epoxy-mio-intermediate-tds/ page.
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