Celotex (Phenolic Resin)

Rigidity, electrical insulation and mechanical strength in a technical laminate. The reference material for high-demand electrical, electronic and mechanical applications.

The material

What is Celotex?

Celotex, also known as Pertinax or laminated phenolic resin, is a composite material formed by layers of kraft paper impregnated with phenolic resin and pressed at high pressure and temperature. The result is a rigid material, mechanically resistant, with excellent electrical insulation properties and great dimensional stability. At Plásticos Ferplast we supply Celotex sheets in different thicknesses and formats, and we also manufacture custom machined parts. It is the standard material in the manufacture of electrical panels, printed circuit boards, templates, machining fixtures and structural elements in environments where electrical insulation is a priority.

Technical properties of the material

Excellent electrical insulation

Ideal for panels, bases and component supports.

High mechanical rigidity

With low weight compared to other engineering materials.

Moderate chemical resistance

To oils, greases and most weak chemical agents.

Easy to machine

It can be milled, drilled, sawed and cut with standard tools.

Dimensional stability

Under normal conditions of use and temperature.

Thermal resistance

Up to 120°C in continuous use.

Competitive cost

Economical compared to other engineering materials.

Homogeneous surface

Characteristic brown color, uniform appearance.

Main technical data

Main material properties according to international standards:

Density (g/cm³) 1.35–1.45 ISO 1183
Flexural strength (MPa) 90–120 ISO 178
Flexural modulus (GPa) 6–8 ISO 178
Tensile strength (MPa) 60–80 ISO 527
Dielectric strength (kV/mm) 10–20 IEC 60243
Continuous use temperature (°C) 120
Water absorption 24h (%) 1.0 ISO 62
Rockwell hardness M80–M100 ISO 2039

Sectors where it is most used

  • Electrical and electronic industry.
  • Machinery and tooling manufacturing.
  • Laboratories and measuring equipment.
  • Aerospace and defense industry.
  • Renewable energy and industrial electrical installations.

Formats and supply

We supply Celotex in the following standard formats, with the possibility of custom cutting and machining:

Celotex sheets

Thicknesses from 1 to 50 mm. Standard formats 1000×2000 mm. Color: characteristic brown.

Cut to size

We cut Celotex sheets to the exact dimensions you need.

CNC machined parts

We manufacture parts, templates and machining fixtures from technical drawings.

Applications

Common applications of Celotex

Due to its electrical insulation and rigidity properties, Celotex is used in multiple industrial sectors.

Electrical panel bases and supports

Control panels and industrial electrical installations.

Machining templates and fixtures

For precision assembly workshops and processes.

Insulation for transformers and motors

Electrical insulation components in machinery.

Separators in industrial electronics

Spacers and insulation elements.

Work surfaces and guides

In precision machinery and instrumentation.

Laboratory equipment supports

Structural components in instrumentation and measurement.

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Frequently asked questions

Celotex is a kraft paper laminate impregnated with phenolic resin, also known as Pertinax or FR-2. It is used primarily for its electrical insulation and mechanical rigidity.

Yes. Celotex machines well with standard tools: milling, drilling, sawing and cutting. It produces dust during machining, so adequate ventilation is recommended.

Celotex has some moisture absorption, which may slightly affect its electrical properties in very humid environments. For applications in humid environments, improved versions such as FR-4 (fiberglass) are recommended.

Celotex (Pertinax / FR-2) uses paper as substrate, while FR-4 uses fiberglass. FR-4 has better mechanical and dielectric properties, especially in humid conditions, and is the standard in consumer electronics.

Yes. We cut Celotex sheets to the dimensions you need, and we also manufacture CNC machined parts according to technical drawings.

What those who already trust Ferplast say

We have been using Celotex from Ferplast for our machining templates for years. Consistent material, easy to work with and fair price.

Workshop Manager Precision machining company

For the base of our industrial electrical panels, Celotex is the standard. Ferplast always has stock and delivery times are very good.

Purchasing Manager Electrical panel manufacturer

Why choose Plásticos Ferplast?

Personalized service

We handle each project uniquely, adapting to the exact needs of each client.

Specialized advice

Over 70 years of experience enable us to recommend the optimal material and process for each application.

Minimum delivery times

We manufacture and supply in the shortest time possible, with express service available in 24h.

Maximum precision

State-of-the-art CNC technology for precise parts and impeccable finishes.

Do you need custom Celotex?

Tell us the dimensions and we will prepare a quote the same day.

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