Mica Gaskets

Mica Gaskets

Mica Gaskets

Advanced Seals & Gaskets Ltd are able to stock and convert a number of electrical insulation materials in the form of papers, resins, laminates and plastics - this is thanks to the great network of material suppliers we have built a relationship with over the years.  Just one of the members of this electrical insulation group is a material called Mica.  Mica is just one of many materials which we can offer for electrical uses, which like others has its own unique sets of excellent properties.

Mica is made by bonding layers of mica paper together with a resin, which are cured into a choice of rigid or flexible boards in thicknesses ranging from 0.10mm to 50mm and in sheet and roll form which we can convert into gaskets.  Our in-house sales and production teams work closely with customers following their drawings or samples to create an exact match ensuring the production of the perfectly fitting gasket which is less likely to fail when in use.  Whether it’s a one off simple square or rectangular shape or thousands of a more bespoke gasket with multiple holes- we can offer a solution using one of our many presses and CNC machines.

Product Enquiry

For information on Mica Gaskets please complete the following quick enquiry or call us on +44(0)1384 252555.






    Key Characteristics of Mica

    • Colour: muscovite (white) micaand phlogopite (green) mica.
    • Sheet Size: 1000 x 1200 mm
    • Thicknesses: 01mm - 50mm (depending on grade)
    • Density: 2.6 – 3.2 gm/cm3
    • Temperature Range:  500°C to 1000°C (depending on grade taken)
    • Flame resistance:Flame retardant and non-flammable
    • Chemical resistances: inert to water, most acids (except hydrofluoric and concentrated sulphuric), alkalis, conventional solvents and oil.

    Full technical data can be supplied upon request,
    or downloaded from our online portal.

    What are Mica Gaskets?

    Mica is an Electrical insulation gaskets are available in one of two colours (depending on grade)-  these Mica Gaskets are used as spacers or gap fillers, taking the form of strips, pads, washers or intricate cut shaped pieces of material which are used for electrical insulation applications where they help restrict the flow of electric current, by supporting electrical conductors - without allowing the current to pass through.   Mica is a widely used mineral that belongs to a large group of alumina, iron, calcium, magnesium and alkaline mineral silicates, the material itself is available in two mineral types of mica, Muscovite and Phlogopite, available in a choice of rigid or flexible sheets.

    Why use Mica Electrical Insulation Gaskets?

    Gaskets made from Mica, as with other Electrical insulation materials are used to provide a barrier to restrict the flow of electrical current, protecting electrical conductors from coming into contact with people or tools during installation, repairs or when an electrical appliance or device is being used.

    Mica gaskets provide thermal, electrical and flame resistance as well as rapid heat transfer and mechanical strength which help electric devices, foundries and manufacturing plants deal safely with excess heat.  These excellent properties make Mica perfect for use as fire door fittings and heat shields within vehicles and aeroplanes.

    Benefits of Mica

    • Heat Resistance up to 1200ºC (rigid Phlogopite)
    • Excellent flexural strength and easy to be punched and machined
    • Excellent dielectric strength and low electrical conductivity.
    • Incombustible
    • Asbestos, and halogen free
    • Excellent resistance to acids (excluding sulphuric acid), bases, mineral oils and solvents

    Other Types of Electrical Insulation Materials Available

    Advanced Seals & Gaskets work with a multitude of material manufacturers, giving our customers more choice and ensuring we can offer a solution to just about any application, our most popular alternatives to Mica gaskets include:

    Epoxy Glass - a green coloured material with good mechanical strength, good chemical, electrical and radiation resistance, low moisture absorption and a working temperature range of up to +120℃.

    Kapton - is a polyamide film which offers a combination of mechanical and tear strength along with chemical, electrical and thermal properties that enables the gasket to withstand vibration and extreme temperatures in demanding environments.

    Leatheroid - is a grey/blue coloured paper gasket material, also sometimes called Elephantide.  This material is used within the electrical industry to insulate hot elements.

    MYLAR is an extremely strong, flexible polyester film.  MYLAR is an excellent insulation material with dielectric strength, moisture resistance and is an excellent insulation material.

    Nomex can be manufactured using nomex paper or nomex board, it can withstand high temperatures, has high mechanical and dielectric strength, and is  an excellent insulation material for all kinds of electrical equipment and applications.

    Presspahn is a brown coloured material,  manufactured using kraft wood pulp.  Presspahn sheets have excellent physical and mechanical properties, generally used as electrical insulation.

    SRBF is resin bonded fibre material which is tough and rigid, with an operating temperature of 120℃, low water absorption and is resistant to wear, impact chemicals.

    SRBP (synthetic resin bonded paper) is manufactured using layers of paper and synthetic resins.  This material is suited to high and medium voltage application.  SRBP has good mechanical and excellent electrical insulation properties, with low water absorption.

    Valox is an excellent electrical insulation material which also offers flame retardant properties.

    PTFE is a non- conductive plastic material used to produce electrical insulation sheets.  PTFE sheets are suitable for high temperature applications and have a high melting temperature.  This material has excellent dielectric properties and can be often found used in circuit boards.

    PVC is a tough, lightweight abrasion, chemical and moisture resistant material which has good dielectric strength making it a great material to use for electrical insulation applications.

    Advantages of Using Mica Gaskets

    Mica gaskets have a number of excellent properties which bring advantages to using this material.  Mica gaskets offer resistance to high temperatures, chemical resistance and durability. As Mica materials are available in both rigid and flexible variants, the gaskets cut from them can be used in a wider range of applications including furnace insulations, automotive gaskets, fire protection and electrical barriers.  The two types of Mica available for gasket production are Muscovite and Phlogopite.  Muscovite Mica Gaskets have a higher dielectric strength and greater insulating properties of the two, therefore more widely used in electrical applications and devices.    Phlogopite mica gaskets offer a higher heat resistance than muscovite, it is a poor electrical conductor and can be manufactured in flexible or rigid options.   Phlogopite Mica gaskets can withstand temperatures of up to 1200°C due to its low thermal conductivity, yet high thermal stability, this is essential in industrial applications where temperatures can reach intensely high levels and the correct insulation for machinery and equipment is vital for safety.   Both Mica types are dielectric, meaning gaskets cut from them offer low electrical conductivity, therefore suited for use as electrical insulators in electronic devices for example within circuit boards, industrial machinery, automotive components and medical devices.

    Have a Question About Mica Gaskets?

    Please contact us using the form below or by calling us on +44(0)1384 252555.