Mica has a wide range of applications in many different industries due to its diverse optical, functional and both electrical and thermal insulation properties.
Ground mica is used in joint compound and in gypsum wallboard functioning as both filler and extender. [US Geological Survey]
The reflective properties of ground mica make it a valued ingredient in cosmetic products. Mica is added to eye shadow, lipsticks, blushes, body glitter, nail polish, shampoo, toothpaste and other products to create pearlescent effects.
In the plastics industry ground mica serves as extender in the production of lightweight plastic insulation used to reduce sound and vibration in vehicles. [USGS] It is also used in vehicle fascia and fenders as a filler and to add strength. Mica is also used in plastic as a pearlescent effect pigment.
Coatings and paint for vehicles, ranging from cars and trucks to boats and aircraft, and industrial applications use mica in pigments to create pearlescent effects created when the light is reflected off of mica particles. Mica plays a variety of functional roles in paints and coatings as well.
It serves as an anti-friction, anti-fouling, anti-settling, anti-corrosive, anti-tarnish and anti-seizing agent. Overlapping layers of mica platelets form a tough shield that improves paint integrity and durability. Mica can act as a reinforcing agent to reduce cracking, peeling and checking in the dry film and prevent shrinkage and sheering of the paint. Muscovite mica is an important technical additive in specialty paints and coatings, increasing resistance to weathering and promoting durability by reducing chalking, cracking and corrosion.
Ground mica is used as an additive in drilling muds. It serves both as a lubricant and a sealer to fill in porous areas of the drill hole wall.
Mica is used in a number of applications in the automotive supply chain. In automotive paints and coatings mica creates a pearlescent visual effect. Plastics for vehicle bumpers, mirror casings, fascia and insulation materials use mica as a filler.
Ground phlogopite mica, known for its heat resistant properties, is found in automotive brake linings. The rubber industry adds mica to selected products where it functions as an inert filler. Electrical components in vehicles rely on mica’s electrical insulation properties. Mica is used in other vehicle components as well in as diverse applications as screws, insulations, seatbelts, switches, valves, brake shoes, clutch pads and sensors.
Mica is an excellent insulator valued for its dielectric strength, an ability to withstand electric current. Sheet and fabricated muscovite mica are used in capacitors and medical electronics among others, such as in electric components found in many industrial and household products ranging from transformers and commutators to hair dryers, space heaters and dimmer switches.
It is found in semi-conductors, circuit boards, and lithium ion batteries. Ground mica can be used in electrical cables and to make mica paper (reconstituted mica) which also is used for electrical insulation.