Editing Glass fiber (section)

==Fiber formation==
Glass fiber is formed when thin strands of [[silica]]-based or other formulation glass are [[extrusion|extruded]] into many fibers with small diameters suitable for [[textile]] processing. The technique of heating and drawing glass into fine fibers has been known for millennia, and was practiced in Egypt and Venice.<ref>{{cite book |doi=10.1016/C2016-0-04634-X |title=Inorganic and Composite Fibers |date=2018 |publisher=Elsevier |isbn=978-0-08-102228-3 }}{{page needed|date=August 2024}}</ref> Before the recent use of these fibers for textile applications, all glass fiber had been manufactured as [[Staple (textiles)|staple]] (that is, clusters of short lengths of fiber).

The modern method for producing glass wool is the invention of [[Games Slayter]] working at the [[Owens-Illinois Glass Company]] ([[Toledo, Ohio]]). He first applied for a patent for a new process to make [[glass wool]] in 1933. The first commercial production of glass fiber was in 1936. In 1938 [[Owens-Illinois Glass Company]] and [[Corning Glass Works]] joined to form the [[Owens-Corning Fiberglas Corporation]]. When the two companies joined to produce and promote glass fiber, they introduced continuous [[Filament fiber|filament]] glass fibers.<ref name = "Lowenstein">{{cite book|last = Loewenstein|first = K.L.|year = 1973|title = The Manufacturing Technology of Continuous Glass Fibers|publisher = Elsevier Scientific|location = New York|pages = 2–94|isbn =978-0-444-41109-9}}</ref> Owens-Corning is still the major glass-fiber producer in the market today.<ref>{{cite web |url= http://www.researchandmarkets.com/reports/592029 |title= A Market Assessment and Impact Analysis of the Owens Corning Acquisition of Saint-Gobain's Reinforcement and Composites Business |date= August 2007 |access-date= 2009-07-16 |url-status= dead |archive-url= https://web.archive.org/web/20090815131929/http://www.researchandmarkets.com/reports/592029 |archive-date= 2009-08-15 }}</ref>

The most common type of glass fiber used in fiberglass is ''E-glass'', which is [[Borosilicate glass|alumino-borosilicate glass]] with less than 1% [[w/w]] alkali oxides, mainly used for glass-reinforced plastics. Other types of glass used are ''[[A-glass]]'' (Alkali-lime glass with little or no boron oxide), ''[[E-CR-glass]]'' (Electrical/Chemical Resistance; alumino-lime silicate with less than 1% w/w alkali oxides, with high acid resistance), ''[[C-glass]]'' (alkali-lime glass with high boron oxide content, used for glass staple fibers and insulation), ''[[D-glass]]'' (borosilicate glass, named for its low dielectric constant), ''[[R-glass]]'' (alumino silicate glass without MgO and CaO with high mechanical requirements as ''r''einforcement), and ''[[S-glass]]'' (alumino silicate glass without CaO but with high MgO content with high tensile strength).<ref name=ullmann1>
{{Cite book
|last = E. Fitzer|chapter = Fibers, 5. Synthetic Inorganic
|title = Ullmann's Encyclopedia of Industrial Chemistry
|publisher = Wiley-VCH Verlag GmbH & Co. KGaA
|location = Weinheim, Germany
|doi=10.1002/14356007.a11_001 |display-authors=etal|year = 2000
|isbn = 978-3527306732
}}</ref>

Pure [[silica]] (silicon dioxide), when cooled as [[fused quartz]] into a [[glass]] with no true melting point, can be used as a glass fiber for fiberglass, but has the drawback that it must be worked at very high temperatures. In order to lower the necessary work temperature, other materials are introduced as "fluxing agents" (i.e., components to lower the melting point). Ordinary A-glass ("A" for "alkali-lime") or soda lime glass, crushed and ready to be remelted, as so-called [[cullet]] glass, was the first type of glass used for fiberglass. E-glass ("E" because of initial electrical application), is alkali free, and was the first glass formulation used for continuous filament formation. It now makes up most of the fiberglass production in the world, and also is the single largest consumer of [[boron]] minerals globally. It is susceptible to chloride ion attack and is a poor choice for marine applications. S-glass ("S" for "Strength") is used when high tensile strength (modulus) is important, and is thus important in composites for building and aircraft construction. The same substance is known as R-glass ("R" for "reinforcement") in Europe. C-glass ("C" for "chemical resistance") and ''[[T-glass]]'' ("T" is for "thermal insulator" – a North American variant of C-glass) are resistant to chemical attack; both are often found in insulation-grades of blown fiberglass.<ref name=redorbit>[http://www.redorbit.com/education/reference_library/general-2/inventions/2583670/fiberglass Fiberglass]. Redorbit.com (2014-06-20). Retrieved on 2016-06-02.</ref>
{| class="wikitable"
|+Common Fiber Categories and Associated Characteristic<ref>{{Cite book|url=https://www.worldcat.org/oclc/712545628|title=ASM handbook|date=2001|publisher=ASM International|others=ASM International. Handbook Committee.|isbn=978-1-62708-011-8|edition=10th|location=Materials Park, OH|pages=27–29|oclc=712545628}}</ref>
! Category
! Characteristic
|-
|A, alkali
|Soda lime glass/ high alkali
|-
|C, chemical
|High chemical resistance
|-
|D, dielectric
|Low dielectric constant
|-
|E, electrical
|Low electrical conductivity
|-
|M, modulus
|High tensile modulus
|-
|S, strength
|High tensile strength
|-
| colspan="2" |''Special Purpose''
|-
|ECR
|Long term acid resistance and short term alkali resistance
|-
|R and Te
|High tensile strength and properties at high temperatures
|}