Micarta

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Micarta is a brand name for composites of linen, canvas, paper, fiberglass, carbon fiber or other fabric in a thermosetting plastic. It was originally used in electrical and decorative applications. Micarta was developed by George Westinghouse at least as early as 1910 using phenolic resins invented by 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 and other resin types were also used. Today Micarta high pressure industrial laminates are produced with a wide variety of resins and fibers. The term has been used generically for most resin impregnated fibre compounds. Common uses of modern high pressure laminates are as electrical insulators, printed circuit board substrates, and knife handles.

The Micarta trademark is a registered trademark of Industrial Laminates / Norplex, Inc. (dba Norplex-Micarta)

History[edit]

The following history was compiled by employees of Micarta Industrial Laminates (at the time, a division of International Paper that was located in Hampton, South Carolina, USA) in 1999 and is based on internal and external documents of the division.

HISTORY OF MICARTA

The history of MICARTA products begins with the perspicacity of George Westinghouse and of employee C. E. Skinner -both of whom could recognize a promising technology when they saw it.

In early Westinghouse electrical devices, insulation was bonded onto materials like wood and amber, glass and slate, each of which was limited in terms of performance or cost. In 1905, the Swiss inventor Emil Haefely brought to the United States a new technique -combining shellac with paper and mica to produce sheets or tubes -which so far lacked any application. George Westinghouse perceived the potential advantages of this new material for insulation and immediately bought the patents. The sheet insulation, which Westinghouse identified under the MICARTA trademark, was first applied in generator stator coils.

Haefely had come to the Unites States from Switzerland for the purpose of disposing of his American patents. His proposition was that he would sell existing patents, furnish a certain number of wrapping machines, and furnish all data or improvements made in Basel and future patents he might take out, for fifty thousand dollars.

Meanwhile, Dr. Leo Baekeland (a private inventor-chemist in New York State) was attempting to tame the unmanageable reaction of phenol with formaldehyde in order to make pipe stems which couldn't be chewed through. After years of failure, he finally announced his discovery of a catalyst for the reaction in 1908. C. E. Skinner, Chief Engineer at the Westinghouse East Pittsburgh plant, read about Baekeland's work and promptly presented himself at the inventor's Yonkers Laboratory. Together they developed phenolic formulations for impregnating paper, and within a year, had delivered the first commercial drum of phenolic resin. Dr. Baekeland called his resin "Bakelite". Originally from Belgium, Dr. Baekeland had invented his "Bakelite" during his "retirement". An earlier invention of his was the gaslight photo printing paper. He organized the Nepera Chemical Co. and sold out to the Eastman Kodak Co.

Westinghouse engineers felt Bakelite would be superior to shellac as a binder. C. E. Skinner consulted along with Dr. Baekeland to improve the material. The mechanical strength greatly improved over shellac but dielectric failures and losses were high. A paper coating machine manufacturer designed a machine especially for the use of coating paper with bakelite. Some of the initial problems was that the building where the machine was located became so full of fumes from the Bakelite that workmen could not stay in it. Dr. Baekeland came to East Pittsburgh to help tame the machine.

At the time of his trip Dr. Baekeland was wearing a full beard. After spending an entire day trying to help tame the machine, Dr. Baekeland returned to his hotel in the evening. He told of having to change his clothes, bathe, wash his hair, and have his beard shaved off before he dared to go to the dining room for dinner, he was so saturated with the fumes of his own product.

Westinghouse tried to work out an exclusive offer with Dr. Baekeland for preference in the application of Bakelite as a binder for laminated material as it was a highly technical and costly development. In spite of the protests of Westinghouse, Bakelite, as a liquid resin, along with the Westinghouse technique, was made available to others and these other concerns profited at the experience of Westinghouse.

The central thought of work with Bakelite was its application to parts which were to be used in the construction of electrical apparatus, and no comprehensive plan was made for selling this laminated material to the trade generally. "Micarta" was the term chosen for laminated material, "Moldarta" was the name for molded products. Westinghouse sold the material outside only when the requirements ofits own factories had been satisfied.

Developments utilizing the world's first synthetic thermosetting polymer followed quickly. In 1910, J. Dow invented a condenser bushing for transformers with conducting ink on phenolic¬impregnated paper. In 1912, H. Conrad found that gears cut from thick sheets of Micarta would serve as a noiseless and resilient gear, especially when the sheets were made of cloth instead of paper. No great development was made in this line for a number of years for the reason that Westinghouse was not equipped to market this non-electrical product. It is true that the Westinghouse Company controlled the Nuttall Company, which was in the gear business, but the gear jobbing business was a local business and could not be handled nationally or from a single point.

In 1913, D. J. O'Connor molded a printed top sheet to regular paper, producing a colorful, decorative laminate. Recognizing the potential of his new product, O'Connor left Westinghouse to fund the Formica Corporation which quickly became its chief competitor.

In 1917 it was realized that the silent gear business had great possibilities, and, in order to market it properly, a license plan, under the Conrad patents relating to the use of Micarta as a gear, was evolved. This plan virtually made the local gear jobber Westinghouse's agent for the making and selling of these silent gears. Micarta was furnished by Westinghouse to them in standard plate form. In order to properly launch this plan Westinghouse called together the leading gear jobbers ofthe country and helped them form the American Gear Manufacturers Association. This organization started with eleven member companies. As licensees, the gear companies purchased the Micarta sheets from Westinghouse and supplied the local demand by cutting the teeth in these blanks. The plan worked well and the sales of Micarta for gear purposes multiplied many times in one year. It also developed that Micarta could be used in the making up of timing gears for automobiles, and this market for Micarta became very large.

While it has been evident for some time that there were a large number of non-electric applications for Micarta, the extent of these were dependent upon the price of Bakelite, and the Bakelite Company, believing that its position was secure on account of its patents, made no effort to reduce this price. Moreover, Westinghouse was too dependent upon the Bakelite Company for its supply of this important material. It became the duty of Westinghouse to devise a plan to avoid those patents and also to improve the quality of the resin which would be used as the Bakelite Company had not materially improved its quality for a number of years.

One plan resulted in the production at East Pittsburgh of a resin named "Alurite", which had all of the good qualities of Bakelite and other qualities which Bakelite did not have. There were, however, some patent risks involved in the use of this resin, and Westinghouse did not have the experience or technique for its commercial manufacture. Seeing that the situation was critical and important, in 1927, the decision was made that Alurite should be made in quantities sufficient to supply all of the Company's special needs, although purchases of Bakelite from the Bakelite Company were to continue for the greater portion of its needs. The making of Alurite gave Westinghouse experience, technique and cheaper material, which made it independent of the Bakelite Company and widened the use of Micarta.

About the same time that the manufacture of"Alurite" was decided upon, the Stokes and Smith Company of Philadelphia, discovered a resin made from phenol and furfural, the latter a crop byproduct made from corn cobs, oat hulls, etc. This "Durite" appealed to Westinghouse because of its cheapness. A contract was entered into with Stokes and Smith whereby Westinghouse was to assist in the developing this resin and obtain a price differential. This connection worked out very nicely. The use of Durite lowered the cost of Micarta not only when it is made of Durite but when made of Bakelite as well. The competition of Durite lowered the price of Bakelite to the point where the price of resin was one-half of the price it was in the beginning. As the price of resin was reduced, the file of non-electric application of Micarta was extended.

After its application to gears, Micarta was applied to airplane propellers, where it was very successful. Lightweight Micarta airplane propellers were produced in 1915. 1917 saw the first airplane pulley for control cables. Then came restaurant and other trays, furniture and building material, such as wall coverings and panels. Unfortunately, however, Westinghouse was not in position to take advantage of the opening of this market or potential market, as it had not expanded its Micarta manufacturing facilities ..

The uses for Micarta laminates increased almost exponentially from 1915 to the 1930's, giving a boost to an assortment of emerging technologies. In many of these applications, Micarta laminates are still employed today.

In energy, coal was still king, and coal mining a booming industry. In Pittsburgh, the Mine Safety Appliance Company had been founded to produce mining equipment; this small local outfit approached Westinghouse with a request for a molded plastic hat which would be light in weight, impact resistant, and comfortable to wear. In 1921 Westinghouse engineers came up with a phenolic-cotton helmet which met the requirements. These safety helmets would be molded by the millions through the next thirty years.

In 1927, E. R. Perry was issued a patent for ship propeller bearings made with laminates up to four inches thick. When lubricated with water, these bearings demonstrated silent, low friction operation. Perry went on to become the Micarta Division manager, and the Micarta technology was applied with great success to paper mills and to steel rolling mills. Micarta ball bearings were sold and still are being sold through the J. T. Ryerson Steel Company.

As the price of the resin decreased, molding products began to displace porcelain in the wiring device industry in the late 1920's and early 1930's.

Micarta laminates had first been enlisted for decorative applications in 1913, but because phenolic resins came only in a color range of dark brown to black, the earliest laminates were rather somber in appearance. For years Westinghouse sought a colorless polymer that would be stain resistant and compatible with phenolics. The search for an alternative resin led to three joint ventures. Negotiations began with American Cynamid Company to develop a urea resin which had solid colors and promised more permanency of color. These developments and others led to the use of melamine formaldehyde resins for the surface sheets of decorative Micarta. This resin was transparent and had an index of refraction matching that of alpha cellulose paper. Hence a clear top sheet could be bonded to the underlying printed sheet; suddenly, Micarta laminates would be made in an array of colors.

In 1931, L. O. Marsteller produced a lightweight building panel by adding a top plate of aluminum to a phenolic laminate. With one stroke, he had sponsored two future businesses for Westinghouse: the Architectural Systems Division, and the fabrication of metal clad laminates for printed circuit boards.

The 1930's saw the development of several new synthetic polymers; one of these--rayon--was made by pulling fibers from a solution through tiny dies. The fibers were wrapped around a spinning bucket (at speeds of more than 10,000 rpm) and subjected to a sudden tension which oriented the fiber and greatly increased its tensile strength. Buckets of wood, aluminum, steel, and other materials had been tried. But because the rayon fibers gashed the surface of the buckets -which often spun apart with disastrous results -their usefulness was short-lived. In response to an urgent appeal from the fiber industry, H. R. Moyer of Westinghouse came up with a phenolic liner fabric bucket with a smooth surface. These buckets proved virtually indestructible, and soon were found in every rayon mill. Thus began a love affair between Westinghouse and the textile industry, which found further uses for Micarta products in quill bobbins, shuttle, and other loom parts.

In 1928, the Micarta Division had moved to a new site in Trafford, adjacent to the Trafford Foundry which guaranteed a good supply of steam for the hydraulic presses. Through the 1930's, the production consisted of industrial laminates and moldings for the electrical industry, and of decorative laminates for the construction industry. By 1930, however, the rumblings of war in Europe foretold the imminent shelving of peace-time applications. The Micarta Division was asked to look into the potential of their laminates for some new applications in the military.

In 1940, F. Nagel responded to one such request for a laminate for curved aircraft parts. He developed a Micarta material which would be press molded into sheet form but only partially cured. Later, it could be bent -with only minor heat and pressure -in inexpensive wooden molds. (This "post-forming" Micarta was diverted after the war to make countertops with rolled edges.)

Micarta aircraft pulleys, first produced in 1917, had been used on many well-known airplanes (notably the Pan Am Clippers) to guide the control cables from the cockpit to the rudder, ailerons, throttles, and other movable parts. In 1939, the Army asked the Micarta Division to increase its production from 1000 per month to 50,000. The Division did even better than that: during the next few years, production increased constantly, reaching a record 1.3 million pulleys a month. By 1944, almost every American warplane had its Micarta pulleys (for example, there were 41 on the P-39, and 768 on the B-29).

Shortly after America's entry into the war, the Army came to Trafford, bringing a challenge for Ivan 1. Morris. Could a Micarta helmet liner be produced to fit inside the steel outer helmet used by infantrymen? Drawing on the old mine safety hat technology, Mr. Morris quickly produced designs and constructions of phenolic cotton cloth; the first liner was molded in May 1942. However, the curing schedule was far too long for the great number of parts needed. Trafford and R&D chemists solved this problem by changing the base resin and the catalyst, reducing the curing time by a factor of seven. Production at Trafford, and subsequently at the Bryant Electrical Corporation plant (Bridgeport, CT) ultimately resulted in 26 million Micarta helmet liners by 1945.

Westinghouse had observed the founding of Owens-Coming Fiberglass in the 1930's, and had recognized the virtues of fiberglass as a reinforcing fiber. Moreover, the excellent thermal and dimensional stability of the material was vital in transformer components. J. G. Ford of Sharon and R. W. Auzier at R&D worked with the Micarta formulations to develop a laminate made of glass cloth and phenolic resin. The success of this program in 1941 suggested the swift implementation of glass-reinforced products.

Sure enough, an application turned up at the Naval laboratories in Annapolis, where it was suggested that the melamine resins would offer certain advantages for shipboard insulators. In response, C. J. Straka developed a glass-cloth melamine laminate which was used in all panels, switch gear, transformers, and motors in submarines and other Navy ships.

During his work on a variety of laminates, Straka had experienced the difficulty of obtaining a good bond between most organic resin and glass fibers; normally, this was a disadvantage. In 1944, Westinghouse was approached by the Army for a lightweight body armor for use in flak jackets and by infantrymen. Straka quickly realized that the weak bonding of glass-containing laminates could be turned to good account: if a fabric could be caused to delaminate upon impact, large amounts of energy would be absorbed. The product which resulted -"Doron" ¬was based on styrenated phenolic and glass cloth. Developed too late to be widely used in World War II, it was produced in considerable quantities for the Air Force during the Korean conflict.

As World War II ended and the American soldiers came home, the demand for military products gave way to an expanding civilian market. And so the attention of the Micarta Division reverted to its traditional market areas: decorative laminates and insulating materials. Some novel opportunities quickly emerged in both areas. The return of the servicemen brought a little boom to the construction industry; housing and furniture were in great demand. Furniture had traditionally been made of wood or wood veneer. Micarta laminates offered a natural replacement of the increasingly scarce wood veneers, and soon were found on tables, dressers, cabinets, kitchen cupboards, counters, and in bathrooms. Many new "wood grains" were designed (and complicated printing patterns up to four colors at a time) ultimately led the Division to employ its own printing presses and to experiment in the art of ink formulation.

To accommodate this proliferation of new presses, Westinghouse purchased all the stock of the Plywood Plastics Corporation in Hampton, South Carolina, on July 9, 1951. PPC was originally built in the late 1930's to manufacture plywood for use in World War II. One of the uses was for plywood for PT boats. In the beginning, Plywood Plastics Corporation was operated as a subsidiary of Westinghouse Electric Corporation. Westinghouse moved the headquarters of the Micarta Division to Hampton in 1955.

On January 1, 1956, the official plant name was changed to the Hampton Plant of the Micarta Division of Westinghouse Electric Corporation. This was confirmed by the addition of a 45-foot sign with blue metal lettering.

In 1957, a million man hours of safe operation without a lost-time accident was completed in the Hampton Micarta plant. The National Safety Council presented the "Award of Honor" to the Micarta Division.

New applications for insulating materials also surfaced after World War II. Polyester resins providing excellent chemical resistance and good electrical properties had been born of necessity during the war. The lack of solvents and the ability to cure quickly at low pressures soon resulted in laminates and products with the romantic names of gunk molding, premix molding, SMC, and BMC. The Micarta Division developed many applications for all of these new products, but the most important, for the electrical industry, were the arc and track resistant laminates and moldings containing an aluminum-oxide trihydrate filler. First employed by scientists at Rostone and General Electric, the filler was quickly adapted for use in Westinghouse products; it is used widely for protection from electric arcs.

In the early stages of work on the Naval reactors program, the need for a lightweight secondary neutron shield was recognized. Work at R&D had suggested that polyethylene filled with boron salts would provide a successful shield, and the Micarta Division began to produce this material. At first, it was molded in large hydraulic presses which produced sheets 4' x 5' x 2" thick; feeling, however, that the long press cycle of heating and cooling was excessive, Micarta engineers developed an extrusion system which could make sheets up to four inches thick and eight feet wide in continuous lengths.

Finally, Micarta laminates offered strong but lightweight material for the aerospace industry. In 1954, President Eisenhower displayed beside his desk the first rocket nose cone to successfully re-enter the earth's atmosphere; this nose cone was made of glass melamine laminate made by the Micarta Division. The first Titan ICBM heat shield to survive re-entry was built in Hampton in 1958. A woven spiral tape ofpure quartz yarn and a high-temperature phenolic resin were the materials employed.

Drawing upon the technologies of decorative laminates, the Micarta Division now began to produce copper-clad laminates (by molding phenolic paper to a thin layer of copper foil) for the burgeoning electronics industry. At first these laminates were sold only to the Radio-TV Division in Metuchen, NJ; however the capacity of the new facility permitted outside sales and these soon gave the Division a dominant position in copper-clad laminates for electronics. The subsequent development of epoxy resins (which had excellent adhesion to glass fibers) permitted expansion into new types of copper-clad. The problem of measling (an incompatibility at fiber crossover points) plagued the industry for a while but was finally solved by J. A. Harrington.

The copper-clad laminates were made from impregnated materials (paper and glass cloth) treated with an epoxy resin. They were molded in various sheet sizes and thicknesses. These sheets were cut into panels for individual customers around the world who manufactured electronic circuitry. These circuit boards were used in computers, television, cameras, telephones, radios, calculators, smoke detectors, automobiles, industrial machinery, and other electronic equipment.

Various capacity expansions were made over the years. The Erie press was installed in Hampton in 1961, which at that time was the largest laminate press built in the United States. In 1966, the world's largest laminate press was installed. Weighing 740,000 pounds, the press was manufactured by Siempelkamp & Company of Krefeld, West Germany, and can produce 17,280 square feet per press load. This press addition brought the total expansion expenditures in slightly less than two years to $3,750,000.

In October of 1966, the Hampton plant once again achieved 500,000 man hours with no lost time incidents.

Continued growth in the copper-clad laminates area brought the Micarta Division to its expansion in Pendleton, South Carolina in 1981. The expansion in Pendleton, South Carolina, consisted of a $36 million plant built on a 95 acre tract with 200,000 square feet of manufacturing and office space.

In April, 1983, Westinghouse acquired Fortin Industries, a copper clad laminate manufacturer located in Sylmar, California; Great Britain, and France. In July, 1988, the Business Unit was reorganized with Hampton being divided in half. One half was known as the Specialty Materials Division, one half as the Copper Laminates Division. The Pendleton facility along with the Fortin plants were part of the Copper Laminates Division. In July, 1988, the headquarters of the Copper Laminates Division moved to Sylmar, California, with the Hampton and Pendleton sites reporting to Sylmar.

The Specialty Materials Division segment of Hampton consisted of industrial and decorative laminates. Headquarters were located at Bedford, PA, with plants in Hampton, SC, and Abingdon, VA. As a result of corporate restructuring, in January, 1990, the Hampton facility once again became a stand alone plant as the Specialty Materials Division. In June, 1991, the copper clad product line was moved to Pendleton, SC, and production of that product line in Hampton ceased. In June, 1992, the Copper Clad Laminates Division was sold to Allied-Signal Incorporated. The sale included the plants in Sylmar, CA, Great Britain, France, and Pendleton, SC.

On December 18, 1992, the Hampton plant became the first U. S. laminator to become certified to the ISO 9002 standard. The facility was certified by Lloyd's Register Quality Assurance Limited.

On September 1, 1995, Hampton was purchased by International Paper Company. The Hampton facility became part of the Decorative Products Division. As true throughout it's entire life the facility continues to have two distinct product lines -industrial and decorative. The decision seems to have been made to treat the different product lines as two separate businesses with each reporting to a different business manager. The industrial side maintains the Micarta trademark while the decorative laminates will be marketed under a "sister" plant's trademark of Nevamar. Other plants in the Decorative Products Division (DPD) include Nevamar, Masonite Panels, Pluswood, Gamble Brothers, and Uniwood / Fome-Cor.

On December 20, 1995, the plant passed its triennial ISO 9002 audit, and continued to remain certified. The plant sits on a 75 acre site with a manufacturing and office space of 825,000 square feet. The number of employees currently stands around 600, but at one time boasted of as many as 1100 employees.

PRODUCTS The resins used at the Hampton Facility generally are of the thermosetting variety. Their cross linked or three-dimensional type of molecular structure possesses a good temperature resistance, high strength, chemical and solvent resistance, abrasion resistance, etc. The most common resins are reaction based products based on phenol and formaldehyde Because they are brittle and friable material, it is necessary to reinforce them with such filler materials as paper, cotton, fabric, wood, glass fabric, or synthetics. The type of filler depends on such considerations as cost, complexity of design, and electrical, chemical, and mechanical properties needed. In addition to phenolics, industrial Micarta resins include epoxy, melamine, silicone, and at one time polyester. The most commonly used decorative resins are melamine formaldehyde and phenol formaldehyde reaction products. Our products may be laminated or molded. If laminated, they are subjected to intense pressures on huge laminating presses. If molded, they are subjected to heat and pressure in semiautomatic compression or transfer molds. For a brief period, injection molding was performed.

APPLICATIONS The Hampton facility manufactures thermosetting plastics in many combinations for worldwide use. Product applications range from ballistic armor to rocket launching tubes; electrical and electronic components; space-age communication devices; knife handles; steel mill bearings; decorative laminates for recreational home and office furnishing; and B-stage prepregs for rigid and flexible composites. Each application requires a product manufactured to precise specifications and delivered to customers within twenty-four hours to four weeks from receipt of order. Our customer base consists of thousands of companies in defense, industrial, residential, construction, an commercial related industries.

Decorative Micarta Laminates The decorative products consists of a broad line ofdecorative surfacing patterns which are laminated to various cores and used as decorative surfacing. Uses vary from counter tops, stove fixtures, furniture (office and residential), interiors ofrail cars, interiors ofships, flooring for computer rooms, bowling alley lanes, engraving stock, wood paneling, special conductive surfaces, working surfaces for commercial sewing machines, and industrial ski surfaces. They are manufactured in various sizes, various finishes, thicknesses, colors, post forming, and non-post forming.

Molded Products Many custom molded items have been made in the Hampton plant over the past forty years. Items such as breaker bases, covers, and insulators are used in the electronics industry. Many are used by the U. S. Navy in ships and submarines. Third rail insulators and switch gear components are used by rapid transit and rail systems. Helmet liners for the U. S. Government, tank helmets, doron for armament vests, and gun sights for large weapons, timing gears for automotive industry, bearings for steel mills, and caster wheels for carts are a few ofthe many items. Using compression, transfer, (and for a time injection) presses with chrome plated, match-metal molds, these items are molded from various molding powders (phenolic, melamine, and diallyphthalate), polyester bulk molding, sheets molding and compound and various impregnated substrates (glass cloth, cotton cloth, and paper).

Industrial Plate Basic raw materials are resin impregnated paper, cloth, or glass fabric. Resins used are phenolic, epoxy, melamine, and silicone. Used in mechanical, chemical, or electrical insulating applications and fabricated parts. Produced in flat sheets 3' x 3',4' x 9' and ranging in thickness from .010" to 17". Also molded in shapes as rods angles, chmmels, and zees.

Tubing Two types: convolute and filament wound. Convolute: resin impregnated paper, cloth, or glass wound on a mandrel under tension, pressure, and heat to the required O.D. Used in mechanical, chemical, or electrical insulating applications, fabricated parts, and as beakers or containers. Produced as cylinders ranging from .250" to 60" LD. and multiple wall thicknesses. Filament wound: resin soaked glass stranding wound in a pattern on a steel mandrel. Used as insulators, beakers, or containers. Produced in sizes ranging from .250" to 60" LD. and multiple wall thicknesses. [1]


Manufacturing process[edit]

Micarta knife handle

Micarta industrial laminates are normally phenolic, epoxy, silicone, or melamine resin based thermoset materials reinforced with fiberglass, cork, cotton cloth, paper, carbon fiber or other substrates. 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.

Micarta industrial laminates are manufactured in dozens of commercial grades.

Applications[edit]

Compressed natural gas 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 handgun grips, guitar fingerboards, nuts[2] and bridges, pool cues, and safety gear such as hard hats. Between 1935 and 1945, Westinghouse's Power-Aire desk fans used blades made of Micarta.[citation needed]

Micarta 259-2 was used as the ablation heat shield material in early ICBM warheads.[3]

See also[edit]

References[edit]

  1. ^ unpublished "History of Micarta" prepared by Debra Harrelson with assistance of the employees of the Micarta Division of International Paper to mark the 100th anniversary of the establishment of International Paper
  2. ^ http://www.stewmac.com/shop/Nuts,_saddles/String_nuts/Micarta_Nuts.html
  3. ^ Heppenheimer, "Facing the Heat Barrier", NASA, 2007

External links[edit]