Plate glass, flat glass or sheet glass is a type of
glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of ...
, initially produced in plane form, commonly used for
window
A window is an opening in a wall, door, roof, or vehicle that allows the exchange of light and may also allow the passage of sound and sometimes air. Modern windows are usually glazed or covered in some other transparent or translucent materia ...
s, glass doors, transparent walls, and
windscreen
The windshield (North American English) or windscreen (Commonwealth English) of an aircraft, car, bus, motorbike, truck, train, boat or streetcar is the front window, which provides visibility while protecting occupants from the elements. Mo ...
s. For modern architectural and automotive applications, the flat glass is sometimes bent after production of the plane sheet. Flat glass stands in contrast to ''
container glass
Container glass is a type of glass for the production of glass containers, such as bottles, jars, drinkware, and bowls. Container glass stands in contrast to ''flat glass'' (used for windows, glass doors, transparent walls, windshields) and ''gl ...
'' (used for bottles, jars, cups) and ''
glass fibre'' (used for thermal insulation, in
fibreglass
Fiberglass (American English) or fibreglass (Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass clo ...
composites, and for
optical communication).
Flat glass has a higher
magnesium oxide
Magnesium oxide ( Mg O), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2− ions ...
and
sodium oxide
Sodium oxide is a chemical compound with the formula Na2 O. It is used in ceramics and glasses. It is a white solid but the compound is rarely encountered. Instead "sodium oxide" is used to describe components of various materials such as glass ...
content than container glass, and a lower silica,
calcium oxide
Calcium oxide (CaO), commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. The broadly used term "''lime''" connotes calcium-containing inorganic ...
, and
aluminium oxide content.
["High temperature glass melt property database for process modeling"; Eds.: Thomas P. Seward III and Terese Vascott; The American Ceramic Society, Westerville, Ohio, 2005, ] From the lower soluble oxide content comes the better
chemical durability
Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engine ...
of container glass against water, which is required especially for storage of beverages and food.
Most flat glass is
soda–lime glass
Soda–lime glass, also called soda–lime–silica glass, is the most prevalent type of glass, used for windowpanes and glass containers (bottles and jars) for beverages, food, and some commodity items. Some glass bakeware is made of soda-lime ...
, produced by the
float glass process (1950s). Other processes for making flat glass include:
*
Broad sheet method (13th century)
*
Window crown glass technique (14th century)
*
Blown plate method (17th century)
*
Plate polishing (17th century)
*
Cylinder blown sheet method
*
Machine drawn cylinder sheet method (early 20th century)
* Rolling (
rolled plate glass,
figure rolled glass) (19th century)
*
Fourcault process (1900s)
*
Float glass (1950s)
*
Overflow downdraw method
The overflow downdraw method or fusion method is a technique for producing ''flat glass''. The key advantage of this technique as compared to the float glass process is that the pristine surfaces are not touched by molten tin. The technique is use ...
(1960s)
The term
plate glass universities
The term plate glass university or plateglass university refers to a group of universities in the United Kingdom established or promoted to university status in the 1960s. The original plate glass universities were established following decisi ...
is used in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
to describe a group – or generation – of universities (in an acknowledgement of the term
red brick universities
A red brick university (or redbrick university) was originally one of the nine civic universities founded in the major industrial cities of England in the 19th century.
However, with the 1960s proliferation of plate glass universities and t ...
, used for an older generation of establishments).
Quality and damage
Scratches can occur on sheet of glass from accidental causes. In glass trade terminology these include "block reek" produced in polishing, "runner-cut" or “over/under grind” caused by edge grinding, or a "sleek" or hairline scratch, as well as "crush" or "rub" on the surface.
[Ron Hanifan Concise Dictionary of Engineering: A Guide to the Language 2014 3319078399 "Scratches occur on sheet glass in all degrees from various accidental causes. Block reek is a chain-line scratch produced in polishing. A runner-cut is a curved scratch caused by grinding. An over/under grind is an imperfection on the edge. A sleek is a hairline scratch. A crush or rub is a surface ..."]
See also
*
Architectural glass
Architectural glass is glass that is used as a building material. It is most typically used as transparent glazing material in the building envelope, including windows in the external walls. Glass is also used for internal partitions and as an ...
References
{{Authority control
Glass types
English inventions