Micarta

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Micarta is a composite of linen or paper fabric in a thermosetting plastic, originally used in electrical and decorative applications. Micarta was developed by George Westinghouse at least as early as 1910 using phenolic resins invented by Dr. Leo Baekeland. These resins were used to impregnate paper and cotton fabric which were cured under pressure and high temperature to produce laminates. In later years this manufacturing method included the use of fiberglass fabric, other resin types were also used. Today micartas are produced with a wide variety of resins and fibers and the term has evolved to generically refer to most resin impregnated fibre compounds. Common uses of modern micartas are as electrical insulators, printed circuit board substrates, and knife handles.

[edit] Manufacturing process

Micarta industrial laminates are normally phenolic, epoxy, silicone, or melamine resin based thermoset materials reinforced with fiberglass, cotton cloth, paper, or carbon fiber. Micarta industrial laminate sheet is a hard, dense material made by applying heat and pressure to layers of prepreg. These layers of laminations are usually of cellulose paper, cotton fabrics, synthetic yarn fabrics, glass fabrics or unwoven fabrics. When heat and pressure are applied to the layers, a chemical reaction (polymerization) transforms the layers into a high-pressure thermosetting industrial laminated plastic.

[edit] Grades

Micarta industrial laminates are manufactured in dozens of commercial grades.

[edit] Applications

Skinner knife with Micarta handle

Compressed natural gas (CNG) storage cylinder in the process of being installed in saddle supports using micarta insulation as an electrical insulator.

The largest use for Micarta industrial laminates is a high strength electrical insulation in power generating and distribution equipment. Laminates are also used in heavy equipment, aerospace, automotive, office equipment, tabletops, countertops, electronic, electrical insulation between pressure vessels or piping and their supports, decorative applications, including knife handles and gun handles, guitar fingerboards and bridges, pool cues and safety gear such as hard hats. Between 1935-1945, Westinghouse's Power-Aire desk fans used blades made of Micarta. Micarta is a trademark of Norplex-Micarta Industrial Composites.