Mica Tapes
Insulation for fire-resistant cables with circuit integrity up to 1000°C
Mica Tapes
Mica tapes are composite materials made of high-purity mica paper bonded to an alkali-free glass-fibre fabric backing and impregnated with a high thermal-resistance silicone resin. This construction provides a protective barrier that preserves electrical insulation integrity during fire exposure, keeping the cable functional at temperatures up to 1000°C depending on the mica grade selected.
In fire-resistant cable construction, the mica tape is applied directly over the conductor with the mica side in contact with the copper. During a fire, while the organic cable materials degrade, the mica layer maintains electrical insulation between conductors, allowing safety circuits — alarms, emergency lighting, fire-suppression and smoke-extraction systems — to remain operational throughout the time needed for evacuation.
Two mica types are available depending on the source mineral: calcined muscovite (750–950°C) and phlogopite (up to 1000°C). Muscovite delivers higher dielectric strength at an optimised cost, while phlogopite provides greater thermal resistance and flexibility for standards that demand higher test temperatures or longer exposure times.
All our mica tapes are halogen-free and produce no toxic gases, complying with the low-smoke requirements demanded in installations where personal safety is paramount. Tensile strength ≥100 N/10 mm guarantees breakage-free taping even at high speed, supporting elevated productivity in automated cable lines.
We manufacture in two grades depending on the taping process: standard grade for general applications, and high-quality grade for high-speed taping and small conductor sections where material handling is more demanding.
How to choose the right one?
The choice between muscovite and phlogopite depends primarily on the test temperature specified in the applicable standard and on the characteristics of the taping process. Phlogopite delivers superior performance at a higher cost, while muscovite is more economical for tests up to 950°C.
Muscovite vs. Phlogopite
| Factor | Muscovite Mica | Phlogopite Mica |
|---|---|---|
| Maximum temperature | 750–950°C | Up to 1000°C |
| Dielectric strength | Higher (≥1.3 kV/layer) | Standard (≥1.0–1.5 kV/layer depending on ref.) |
| Flexibility | Standard | Higher |
| Relative cost | Lower | Higher |
| When to choose | Tests up to 950°C, good cost/performance ratio | Standards with tests at 1000°C, long exposure times |
Selection by standard
| Standard | Test temperature | Recommended mica |
|---|---|---|
| IEC 60331 | 750°C–950°C | Muscovite or Phlogopite |
| EN 50200 | 830°C–950°C | Muscovite or Phlogopite |
| BS 6387 Cat. C | 950°C | Muscovite or Phlogopite |
| BS 6387 Cat. W | 650°C + water | Phlogopite (greater resistance) |
| EN 45545 (railway) | Variable by HL | Per specific requirement |
Technical specifications
The values shown below come from in-house tests and characterise the material's behaviour both during processing and in service.
Muscovite Mica — FR80M28
| Property | Value | Unit |
|---|---|---|
| Thickness | 0.110 ±0.02 | mm |
| Tape weight | 128 ±15 | g/m² |
| Mica content | 80 ±5 | g/m² |
| Glass content | 28 ±2 | g/m² |
| Binder content | 20 ±3 | g/m² |
| Dielectric strength | ≥1.3 | kV/layer |
| Tensile strength | ≥100 | N/10mm |
| Service temperature | 750 – 950 | °C |
Phlogopite Mica — 28GS series
| Property | FR90P28 | FR120P28 | FR160P28 |
|---|---|---|---|
| Thickness (mm) | 0.100 ±0.02 | 0.120 ±0.02 | 0.150 ±0.02 |
| Tape weight (g/m²) | 135 ±10 | 171 ±11 | 206 ±11 |
| Mica content (g/m²) | 90 ±5 | 125 ±5 | 160 ±5 |
| Glass content (g/m²) | 28 ±2 | 28 ±2 | 28 ±2 |
| Binder content (g/m²) | 17 ±3 | 18 ±4 | 18 ±4 |
| Dielectric strength (kV/layer) | ≥1.0 | ≥1.2 | ≥1.5 |
| Tensile strength (N/10mm) | ≥100 | ≥100 | ≥100 |
| Service temperature (°C) | Up to 1000 | Up to 1000 | Up to 1000 |
Construction
| Component | Material |
|---|---|
| Mica paper | Calcined muscovite or Phlogopite |
| Backing | Alkali-free glass-fibre fabric |
| Binder | High-resistance silicone resin |
| Halogens | Halogen-free |
| Toxic gases | Free of toxic gases |
Storage
Minimum 12 months under standard storage conditions, original packaging (20°C).
Values shown are typical and do not constitute binding specifications.
Available variants
Mica type
- Calcined muscovite — 750-950°C, higher dielectric strength
- Phlogopite — up to 1000°C, greater flexibility
Manufacturing grades
- Standard grade — general taping
- High-quality grade — high-speed taping, small conductor sections
Mica content
- 80 g/m² (FR80M28) — standard muscovite
- 90 g/m² (FR90P28) — basic phlogopite
- 125 g/m² (FR120P28) — reinforced phlogopite
- 160 g/m² (FR160P28) — phlogopite max. protection
Delivery formats
The supply format directly influences process continuity and taping efficiency. Material can be supplied in different formats and dimensions adapted to each machine type and production speed.
Pad / Roll (pancake)
Pancake format for taping lines
Spool (TWS / STS reel)
Reel for automatic taping lines
Other formats and dimensions available on request. Custom slitting service available.
Application sectors
Need technical advice?
Our technical team is available to help you select the optimum material for your application. With over 25 years of experience in mica materials for the cable industry, we offer technical assistance for new and existing projects.
Custom slitting
Up to 1200 mm width, ±0.50 mm tolerance
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Spooling
Pad to TWS/STS spool conversion
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Mica taping
5 vertical double-column lines, 80 km/day capacity
View serviceWe process material from our stock or material supplied by the customer. We also offer mica taping of conductors for manufacturers of fire-resistant cables.
Need technical advice?
Our technical team is available to help you select the optimal material for your application.
Local stock in Barcelona · Immediate delivery in Spain and Portugal