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SUBMITTED BY

AMAN SADANA 2008JDS6011,

AMOL JUNGARI 2008JDS6012,

RAHUL BHASKER 2008JDS6015,

MADHIRA VISHAL RAJ 2008JDS6024

1st Sem. M.Des. IDDC, IIT Delhi.

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INTRODUCTION TO GLASSINTRODUCTION TO GLASS

HISTORY OF GLASSHISTORY OF GLASS

INGREDIENTS OF GLASSINGREDIENTS OF GLASS

MANUFACTURING OF GLASSMANUFACTURING OF GLASS

PROPERTIES OF GLASSPROPERTIES OF GLASS

APPLICATIONS OF VARIOUS TYPES OF GLASSAPPLICATIONS OF VARIOUS TYPES OF GLASS

TYPES OF GLASSTYPES OF GLASS

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In common sense:

- Glass in the common sense refers to a hard, brittle, transparent, solid, such as that used forwindows, many bottles, or eyewear, including, but not limited to, soda-lime glass,borosilicate glass, acrylic glass, sugar glass, isinglass (Muscovy-glass), or aluminiumoxynitride.

In technical sense:

- Glass is an inorganic product of fusion which has been cooled to a rigid condition withoutcrystallizing.

In scientific sense:

- the term glass is often extended to all amorphous solids (and melts that easily formamorphous solids), including plastics, resins, or other silica-free amorphous solids.

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4500 B.C. to 3000 B.C. Glass first used in Egypt and Mesopotamia4500 B.C. to 3000 B.C. Glass first used in Egypt and Mesopotamia1500 B.C. First glass vessels made in Egypt1500 B.C. First glass vessels made in Egypt200 B.C. Glass blowing invented in the near East200 B.C. Glass blowing invented in the near East600 A.D. Stained glass windows introduced in Constantinople600 A.D. Stained glass windows introduced in Constantinople1674 A.D. Lead crystal invented by George Ravenscroft in England1674 A.D. Lead crystal invented by George Ravenscroft in England1688 A.D. Cast plate glass1688 A.D. Cast plate glass--FranceFrance1690 A.D. First glassworks in Ireland1690 A.D. First glassworks in Ireland1827 A.D. Glass pressed into moulds1827 A.D. Glass pressed into moulds--U.S.A.U.S.A.1851 A.D. Crystal Palace built in London1851 A.D. Crystal Palace built in London--first prefabricated building of iron and glassfirst prefabricated building of iron and glass1874 A.D. Glass toughened by oil quenching1874 A.D. Glass toughened by oil quenching --FranceFrance1886 A.D. First semi1886 A.D. First semi--automated bottle makerautomated bottle maker --EnglandEngland1903 A.D. First automatic bottle making machine invented by Michael Owens, an1903 A.D. First automatic bottle making machine invented by Michael Owens, an

Irishman, in the U.S.A.Irishman, in the U.S.A.

1903 A.D. Chance discovery of laminated glass by Benedictus in France1903 A.D. Chance discovery of laminated glass by Benedictus in France1915 A.D. Invention of borosilicate glass in the U.S.A.1915 A.D. Invention of borosilicate glass in the U.S.A.

1937 A.D. Photosensitive glass invented by Dalton in the U.S.A.1937 A.D. Photosensitive glass invented by Dalton in the U.S.A.1957 A.D. Glass ceramic made by accident by1957 A.D. Glass ceramic made by accident by StookeyStookey in the U.S.A.in the U.S.A.1959 A.D. Float glass process for plate glass introduced by1959 A.D. Float glass process for plate glass introduced by PilkingtonsPilkingtons in the U.K.in the U.K.

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Silica SandSilica Sand -- 60%60%

Soda AshSoda Ash -- 20%20%

LimestoneLimestone -- 15%15%

AluminaAlumina--SilicateSilicate -- 4%4%

Salt CakeSalt Cake -- 0.9%0.9%

Minor IngredientsMinor Ingredients -- 0.1%0.1%

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Hand glass manufacture Hand glass manufacture

Sheet glass manufacture Sheet glass manufacture

Pilkington float glass process Pilkington float glass process

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BroadBroad sheetsheet..

MoltenMolten glassglass isis gatheredgathered onon aa blowpipe,blowpipe, andandblownblown toto anan elongatedelongated balloonballoon shapeshape .. TheThe endsendsareare cutcut offoff andand thethe resultingresulting cylindercylinder isis splitsplit withwithshearsshears whilewhile stillstill hot,hot, thenthen flattenedflattened onon anan ironironplateplate..

CrownCrown glassglass..

MoltenMolten glassglass isis gatheredgathered onon aa blowpipe,blowpipe, andand aaballoonballoon shapeshape isis blownblown.. TheThe blowpipeblowpipe isisremoved,removed, aa solidsolid ""puntypunty"" rodrod isis attachedattached andand thetheglassglass isis spunspun rapidlyrapidly untiluntil aa discdisc isis formedformed.. TheTheouterouter portionportion beyondbeyond thethe centralcentral knobknob isis thenthen cutcut

intointo panespanes..

BlownBlown plateplate..

ProducedProduced fromfrom BroadBroad Sheet,Sheet, eacheach sheetsheet ofof glassglasswaswas laboriouslylaboriously handhand groundground andand polishedpolished ononbothboth surfacessurfaces.. TheThe plateplate waswas ofof aa sufficientsufficient

qualityquality andand sizesize forfor mirrorsmirrors oror coachcoach glassesglasses..

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Polish plate

Produced by casting glass onto a table andthen subsequently grinding and polishing theglass, originally by hand, later by machine. Anexpensive process requiring a large capitalinvestment.

Cylinder blown sheet.

A similar process to Broad Sheet, except thatlarger cylinders are produced by swinging thecylinder in a trench. The glass is allowed to coolbefore cutting the cylinder, which is then re-heated and flattened. Larger panes and a muchimproved surface quality result.

The above methods of manufacture lasted atleast until the end of the 19th Century. Theearly 20th Century marks the move away fromhand blown to machine manufactured glass.

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Colburn ProcessNihon Sheet Glass Co. used to produce sheetglasses by means of Colburn process since sheetglass can be pulled out horizontally whichallows to have a longer gradual cooling span forproducing soft and sticky glass sheets.

Floating Process

Utilizing the specific gravity difference betweenglass and molten tin as glass is lighter thanmolten tin, glass flows over the molten tin andglass itself is molten by a burner and the finishedglass can be pulled out without any strain which

can be used for mirror .

The Fusion Process

The fusion is the process enables to producesheet glass by not touching impurities containedin the material of a melting chamber. This

process is good for volume production of thinglass.

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The Float Line:

1. Raw material feed

Sand, soda ash, dolomite, limestone and aproportionate amount of cullet are combined toform a batch.

2. FurnaceBatch materials are fed into the furnace. Fullmelting is achieved at around 1 600C.

3. Float bath

A continuous ribbon of molten glass floats alongthe surface of molten tin. Irregularities are meltedout, ensuring flat, parallel surfaces in the glass.

4. Annealing lehrThe glass is annealed and graduallycooled to 200C, to relieve stresses andprevent splitting and breaking in thecutting phase.5. Cutting

The glass ribbon is cut automatically asit moves along the rollers.6. Stacking and offloadingA series of automatic stackers offloadthe glass. The glass is then warehousedfor distribution, using overhead cranesand mobile lifting vehicles.

7. Distribution

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These are the main characteristics of glass:

Solid and hard material

Disordered and amorphous structure

Fragile and easily breakable into sharp pieces

Transparent to visible light

Inert and biologically inactive material.

Glass is 100% recyclable and one of the safest

packaging materials due to its composition

and properties.

These properties can be modified and changed by adding other compoundsor heat treatment.

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Synthetic amorphous silica,is used as the raw materialfor the most expensivespecialty glasses, such asoptical fiber core.

Amorphous SiO2 isused as a dielectricmaterial in integratedcircuits due to thesmooth and electricallyneutral interface itforms with silicon.

Optical instrumentssuch as glasses,cameras, microscopes,telescopes, andplanetarium arebased on glass lenses,mirrors, and prisms.

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BottlesWindow panes

Artifacts

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Laboratory wareReflective glass

Displays

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LensesLighting Equipments

Automobile Glass

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BuildingsGlass Cookware

Mirrors

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- These are the major types of glass with respect to chemical composition.

1) Commercial glass or Soda-lime glass:This is the most common commercial glass and less expensive. The composition ofsoda-lime glass is normally 60-75% silica, 12-18% soda, and 5-12% lime. A lowpercentage of other materials can be added for specific properties such as coloring.

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2) Lead glass:

lead glass is composed of 54-65% SiO2, 18-38% lead oxide (PbO), 13-15% soda(Na2O) or

potash (K2), and various other oxides. When the content of PbO is less than 18% is

known as crystal glass.

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3) Borosilicate glass

Borosilicate glass is mainly composed of silica

(70- 80%), boric oxide B2O3 (7-13%) and

smaller amounts of the alkalis (sodium and

potassium oxides) such as 4-8% of Na2O and

K2O, and 2-7% aluminum oxide (Al2O3).

Borosilicate glass is used for laboratoryglassware

some applications because it is relatively inert,

transparent, more heat-resistant than someplastic

up to a point, and relatively easy to customize

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3) Toughened glass (tempered glass)

Toughened glass (also known as tempered glass)is a type of safety glass that has increased strengthand will usually shatter in small, square pieceswhen broken. It is used when strength, thermal

resistance and safety are important considerations.Using toughened glass on windshields would be aproblem when a small stone hits the windshield atspeed, as it would shatter into the small squaresmaking visibility difficult and it would also belikely that the wind would blow the small squaresinto the driver and passengers. In commercial

structures it is used in unframed assemblies such asframeless doors, structurally loaded applicationsand door lites and vision lites adjacent to doors.Toughened glass is typically four to six times thestrength of annealed glass.

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Sheet glass (sometimes called window glass ordrawn glass) was made by dipping a leaderinto a vat of molten glass then pulling thatleader straight up while a film of glasshardened just out of the vat. This film orribbon was pulled up continuously held bytractors on both edges while it cooled. After 12meters or so it was cut off the vertical ribbonand tipped down to be further cut.

This glass is clear but has thickness variationsdue to small temperature changes just out of

the vat as it was hardening. These variationscause lines of slight distortions. You may stillsee this glass in older houses. The uneven surface of old glass is visible in

the reflection on this window pane.

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The elaborate patterns found on figure rolled glassare produced in a similar fashion to the rolled plateglass process except that the plate is cast betweentwo rollers, one of which carries a pattern. Thepattern is impressed upon the sheet by a printingroller which is brought down upon the glass as itleaves the main rolls while still soft. This glass showsa pattern in high relief. The glass is then annealed ina lehr.

The glass used for this purpose is typically whiter incolour than the clear glasses used for otherapplications.

This glass can be laminated or toughened dependingon the depth of the pattern to produce a safety glass.

Figure rolled glass

The plate glass process starts with sheet or rolled plate glass. This glass is dimensionallyinaccurate and often created visual distortions. These rough panes were ground flat andthen polished clear. This was a fairly expensive process.Before the float process, mirrors were plate glass as sheet glass had visual distortions thatwere akin to those seen in amusement park or fun-fair mirrors.

Polished plate glass

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Glass brick

Glass brick, also known as glass block, is anarchitectural element used in areas where privacy orvisual obscuration is desired while admitting light, suchas underground parking garages, washrooms, andmunicipal swimming baths. Glass block was originally

developed in the early 1900s to provide natural light inindustrial factories.

Security and safety usesGlass brick can admit light without compromisingsecurity, since a typical size of glass brick is 8 by 8

inches, fitting within the lattice of standard 8 by 16 inchcinderblock walls.Electrical circuits such as lights can be isolated byplacing them in a very small room or passagewayoutside the area being illuminated, such that noelectrical leakage is possible. This also helps preventvandalism and theft of bulbs, or removal of bulbs

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Architectural glass is glass that is used as a buildingmaterial. It is most typically used as transparentglazing material in the building envelope, includingwindows in the external walls. Glass is also used forinternal partitions and as an architectural feature.When used in buildings, glass is often of a safety type,which include reinforced, toughened and laminatedglasses.

1 Crown glass: The earliest style of glasswindow2 Glass block3 Cylinder glass4 Sheet glass5 Rolled plate glass6 Figure rolled glass7 Polished plate glass8 Float glass9 Annealed glass10 Laminated glass11 Toughened glass (tempered glass)12 Heat-strengthened glass13 Chemically strengthened glass14 Low-emissivity glass15 Self-cleaning glass16 Insulated glazing17 Evacuated glazing

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- These are some other types of glass with respect to there physical nature andapplications.

1) Float glass1) Float glass

Float glass gets its name from the method of production used to manufacture it. Themolten glass is 'floated' onto a bed of molten tin - this produces a glass which is flat anddistortion free.

Float glass can be cut using a glass cutter and no special equipment is necessary. Floatglass is suitable for fixed and opening windows above waist height.

2) Energy efficient glass2) Energy efficient glass

float glass with a special thin coating on one side which, allows the suns energy to passthrough in one direction while reducing the thermal transfer the other way. The principle

behind this is the difference in thermal wavelength of energy transmitted from the sunand that transmitted from the heat within a room.

3) Self cleaning glass

Some manufacturers produce float glass with a special thin 'photocatalytic' coating onone side. This coating uses the ultraviolet rays from the sun to steadily break down any

organic dirt on the surface using the photocatalytic effect and thus loosen the dirt fromthe glass.

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44)) Patterned (obscured glass)

Made from flat glass, this type has a design rolled onto one side during manufacture. Itcan be used for decorative effect and/or to provide privacy. Patterned glass is availablein a range of coloured tints as well as plain.

5) Toughened (Safety glass)

Toughened glass is produced by applying a special treatment to ordinary float glass afterit has been cut to size and finished. The treatment involves heating the glass so that itbegins to soften (about 620 degrees C) and then rapidly cooling it. This produces a glasswhich, if broken, breaks into small pieces without sharp edges.

6) Laminated glass

As the name suggests, laminated glass is made up of a sandwich of two or more sheets ofglass (or plastic), bonded together by a flexible, normally transparent material.

If the glass is cracked or broken, the flexible material is designed to hold the glassfragments in place.

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7)7) Wired glass

Wired glass incorporates a wire mesh (usually about 10mm spacing) in the middle of theglass. Should be glass crack or break, the wire tends to hold the glass together. It is idealfor roofing in such areas as a garage or conservatory where its 'industrial' look is not toounattractive. Wired glass is generally not considered a Safety glass as the glass stillbreaks with sharp edges.

8) Mirrors

Mirrors are usually made from float glass 4-6mm thick, and silvered on one side. Mirrorsare available for use without a surrounding frame, these usually are made from a type ofsafety glass. Old mirrors, and modern mirrors supplied within a frame, should not beused unframed as any damage to them might cause the glass to shatter dangerously.

9) Picture frame glass

Glass (and plastics) are available specifically for picture framing, these tend to be referredto as 'diffused reflection' glass or plastic. They have high transparency but low reflectiveproperties to reduce reflections when the picture or photograph is viewed.