Mica Mfg Co.p. Ltd. Camac Street Area, Kolkata, West Bengal

Muscovite mica crystals have alternating layers of aluminosilicate and potassium ions.The one-atom thick layersd of potassium ions are very easy to split apart into thinnest film,while aluminosilicate layers are tightly bonded together.As a result, extremely thin sheets of muscovite mica can easily separated,yet these thin sheets are flexible and though.Besides,muscovite mica have excellent dielectric,thermal,mechanical and chemical properties and can withstand rigorous shock and vibration testing.

It is produced in mills of the chaser types. It consists of a cylinderical steel tank with a diameter of 6 to 10 feet and height of 3 to 5 feet. The bottom is lined with wooden blocks laid with the end grain up. Four wooden rollers of 2 to 3 feet in diameter and 1 to 3 feet across the faces revolve round a central shaft, at 13 to 30 r.p.m. These rollers are so fitted that they can be raised or lowered according to the height of the charge in the wall. Cleaned and washed mica scrap is fed into the mills, water is added and the rollers revolve at low speed and churn tha mass until the grinding is complete. After about 36 hours the water is siphoned from the settling tanks, the sludge is dewatered and dried either in steam-jacketed kettles or in a steam-heated drier. The dried product is sieved on multiple-deck vibrating screens, usually in 160 and 325 mesh, and finally bagged for marketing. Wet ground mica have a high metallic lustre or silvery sheen and is free from grit. However, it is a slow and costly process, and therefore, the product is relatively expensive. It is especially used as a pigment extender in paints, particularly in zinc-oxide paint and as a mould lubricant and dusting agent in pneumatic tyres as well as wall paper.

Flexible Mica Sheets are produced from natural Muscovite mica splittings bonded with polyester or silicone resins. The controlled low binder content assures a throughly cured product in which the binder will not ooze or flow from the mica structure. They possess excellent flexibility and adhesiveness to permit winding or wrapping of the sheets at room temperature without heating. They can be formed or bent readily to any shape and will not become brittle and stiff. They can be applied to unusual configuration without tear.

Mica Powder in various forms is obtained by grindingbreaking mica scrap, which is a slow, costly and extremely complicated process, because of the scrap being tough and having a plate like structure. Meticulous care and precaution has to be taken so that there is no deterioration of its natural brilliance, colour and properties.

Micronised Muscovite Mica is extensively used as a pigment extender in various paints and coatings. It is a tough, flexible and transparent mineral that can be ground to less than a micron sieve mesh. Mica particles brighten the tone of the coloured pigments, at the same time, transmit and reflect light resulting in proven decorative effects and design. It increases the gloss of a paint more effectively than spherical or irregularly shaped filler particles of an equivalent size product. Mica also optimize the effect of other pigments by ensuring that the pigment particles are evently spaced in the dried paint film.As mica has good suspension properties, its inclusion reduces running, sagging and settling of paints, as well as, improves weatherability and brushability. The addition of mica makes it possible to redisperse the settled pigment easily at any stage of production by simple stirring.

Laminated Mica or Mica products are employed in electrical engineering already since the turn of the century. Micanite is the name given to sheet material which is made up of fine mica lamellae, called "splittings", bonded together by a variety of bonding agents such as Shellac, epoxy, alkyd or silicone, in order to obtain particular characteristics for specific uses. Variations can be made in the method of manufacture, the types of Mica, and the type of quantity of bonding material used to form thick or thin, stiff or flexible products in the form of sheets, webs or ribbons and also moulded articles.  

Mica has nearly perfect basal cleavage which permits it to be split into thinnest sheets, as low as, .0002 to .0003 inches without any crack or breakage, which in turn helped it to maintain a position of paramount importance as an insulating material.

MICA SHIELDS provide the best protection possible, to flat transparent, sight glasses in water and liquid level gauges and columns in high pressure steam boilers. The SHIELDS retain basic strength and increase the service life of sight glasses when used at increased steam pressures and high working temperatures. MICA SHIELDS also provide perfect visibility for monitoring the natture or degree of combustion in blast furnaces of steam boilers.

Scrap mica basically, is a mica that is below specifications and not suitable for use as sheet mica, because of size, or quality. It is a by-product of mining, trimming, and fabricating sheet mica. Scrap mica is Classified and marketed in the following grades.

The excellent mechanical and electrical properties of natural mica makes it a most reliable and dependable insulators for use as mounting washers for POWER TRANSISTORS, DIODES, RECTIFIERS, IC's and other Semiconductor Devices. Precision punched natural mica insulators and supports help the semiconductors devices fully insulated from the chassis. They play a dual function. To dissipate the heat away from the semiconductors devices and at the same time keeping them cool. Their added advantages are low moisture absorption, high breakdown voltage and high surface leakage resistance.

Band Heaters made of high resistance Nichrome Wire insulated in MicaMicanite. Sheathed in BrassTine Stainless Steel Diametre from 2" to 12". Connection available in screw type, wire leads or pine type.

Cut mica plates are specially made of superior quality muscovite ruby clear mica films, split and gauged to a specified range of thickness varying between 20 to 100 microns into a close controllable tolerance within a micron, suitable for use in the manufacture of silverd mica plates and mica capacitors. Plain smooth surface, clean punched sharp edges, uniform thickness, free from metallic stains, spots, finger prints, scratches, cracks, tears, pin-holes, stones, buckles, ridges, etc., are some of the important points observed while manufacturing cut mica plates. They are manufactured as per ASTM Specifications: D748-71,possessing electrical, physical and visual quality requirements as specified in the following table.

Corrugated Mica made from Muscovite & Phlosovite mica. It is used in manufacturing of Soldering Iron Heating Insulations. Corrugated Mica is supplied as per buyers specification. It stands at a high temperature of upto 1000oC.