WO2012156991A2 - Composition de verre et substrat de verre pour dispositifs d'affichage - Google Patents

Composition de verre et substrat de verre pour dispositifs d'affichage Download PDF

Info

Publication number
WO2012156991A2
WO2012156991A2 PCT/IN2012/000343 IN2012000343W WO2012156991A2 WO 2012156991 A2 WO2012156991 A2 WO 2012156991A2 IN 2012000343 W IN2012000343 W IN 2012000343W WO 2012156991 A2 WO2012156991 A2 WO 2012156991A2
Authority
WO
WIPO (PCT)
Prior art keywords
glass
mole
substrate
glass composition
composition
Prior art date
Application number
PCT/IN2012/000343
Other languages
English (en)
Other versions
WO2012156991A3 (fr
WO2012156991A4 (fr
Inventor
Jeetendra SHEGAL
Original Assignee
Sterlite Technologies Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sterlite Technologies Ltd filed Critical Sterlite Technologies Ltd
Publication of WO2012156991A2 publication Critical patent/WO2012156991A2/fr
Publication of WO2012156991A3 publication Critical patent/WO2012156991A3/fr
Publication of WO2012156991A4 publication Critical patent/WO2012156991A4/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C3/00—Glass compositions
    • C03C3/04—Glass compositions containing silica
    • C03C3/076—Glass compositions containing silica with 40% to 90% silica, by weight
    • C03C3/11—Glass compositions containing silica with 40% to 90% silica, by weight containing halogen or nitrogen
    • C03C3/112—Glass compositions containing silica with 40% to 90% silica, by weight containing halogen or nitrogen containing fluorine
    • C03C3/115—Glass compositions containing silica with 40% to 90% silica, by weight containing halogen or nitrogen containing fluorine containing boron
    • C03C3/118—Glass compositions containing silica with 40% to 90% silica, by weight containing halogen or nitrogen containing fluorine containing boron containing aluminium

Definitions

  • Embodiments in general relate to a glass composition and a glass substrate for use in display and in particular to a glass composition and a glass substrate for use in liquid crystal display [LCD], an electroluminescence display [ELD], a field emission display [FED], plasma display [PD] organic light emitting diode [OLED] etc.
  • LCD liquid crystal display
  • ELD electroluminescence display
  • FED field emission display
  • PD plasma display
  • OLED organic light emitting diode
  • AMLCDs active matrix liquid crystal displays
  • a typical AMLCD comprises, inter alia, two sheets of glass, the first one is vapor-deposited with silicon that forms the basis for the thin-film transistor (TFT) array and whereas the second for the color filter (CF) materials that enables RGB displays.
  • TFT thin-film transistor
  • CF color filter
  • a gap between the two sheets of glass holds a very thin layer of liquid crystal, wherein the gap between the two sheets has to be maintained within tight specifications.
  • the glass also referred to as "glass substrate" used for depositing the silicon for the thin-film transistor array has a unique material composition, which is specifically designed for the application.
  • One method of producing these substrate glasses is the down draw-fusion process [also known as the down-draw process] and is capable of producing a precision fire-polished surface that requires no additional modification such as grinding or polishing prior to use.
  • the US patent numbers 3,338,696 and 3,682,609 disclose fusion downdraw processes which include allowing flow of molten glass over the edges or weirs of a forming wedge, referred to as isopipe. The molten glass flows over converging forming surfaces of the isopipe and the separate flows reunite at the apex or root where the two converging forming surfaces meet to form a glass sheet.
  • the glass which has been in contact with the forming surfaces is located in the inner portion of the glass sheet and the exterior surfaces of the glass sheet are contact free.
  • Pulling rolls positioned downstream of isopipe root capture edge portions of the glass sheet so formed to control the rate at which the glass sheet leaves the isopipe and thus aids in controlling the thickness of the finished sheet.
  • the glass sheet descends from the root of the isopipe past the pulling rolls, it cools to form a solid elastic glass sheet, which may be processed further.
  • various material properties of the glass in the molten stage must be controlled within specified limits during the downdraw process.
  • the molten glass that is supplied to the isopipe has to be free of any inclusion and/or gas bubbles. If the bubbles remain in the final glass sheet that is drawn, the bubbles may cause undesired distortion in the final LCD panel made from the glass sheet. It is thereby desired that the glass sheets drawn are bubble free.
  • the apparatus are to be made up of noble metals such as platinum and titanium which are exorbitantly expensive and hence increase the cost of making apparatus. Any increase in the dimensions will obviously lead to increase in the apparatus cost.
  • refining agents In addition to physical refining, it is known in the prior art that use of some chemical compounds enhances or improves the refining of molten glass. These compounds are known as the refining agents. Notable among them are arsenic oxide and antimony oxides. These refining agents are added with the raw materials and then melted along with the other glass component. These refining agents aids in removal of bubbles or gas entrapped in the molten glass by releasing oxygen that combines with the gas bubbles and increase their buoyancy thereby enhancing the chances of the bubbles to rise in short time span.
  • ⁇ - ⁇ content in the glass Another significant aspect in the glass is the ⁇ - ⁇ content in the glass.
  • ⁇ - ⁇ which is a part of glass structure, causes generation of oxygen bubbles at the platinum-glass interface due to the catalytic conversion of ⁇ - ⁇ into 0 2 and H 2 .
  • H 2 diffuses out of the platinum wall and 0 2 remains in the glass as bubbles. It is thereby desired to have minimum ⁇ - ⁇ content in the glass.
  • An object is to provide a glass composition and a substrate glass.
  • Another object is to provide a glass composition and a substrate glass for display devices.
  • Still another object is to provide a glass composition and a substrate glass compatible with the down draw process.
  • Another object is to provide a glass composition with a refining agent that are efficient in removal of bubbles or glass in molten stage.
  • Another object is to have a glass composition with minimum ⁇ - ⁇ content, and in particular below 300 ppm.
  • Another object is to have a glass composition for use in liquid crystal display [LCD], an electroluminescence display [ELD], a field emission display [FED], plasma display [PD], organic light emitting diode [OLED] etc.
  • LCD liquid crystal display
  • ELD electroluminescence display
  • FED field emission display
  • PD plasma display
  • OLED organic light emitting diode
  • a substrate glass and a glass composition with reduced ⁇ - ⁇ , reduced bubbles or inclusion, wherein said glass composition comprises Si0 2 from about 63.3 to about 71.3 mole %; Al 2 ( 3 ⁇ 4 from about 8.1 to about 12.1 mole %; B2O3 from about 6.7 to about 12.7 mole %; CaO from about 5 to 12 mole %; BaO from about 0.2 to about 3.0 mole %; SrO from about 0.2 to about 4.5 mole %; wherein inclusion of the alkali metal Na 2 0 from about 0.001 to 0.1 mole % decreases the melting point of the substrate glass composition; fluorine from about 0.001 to about 0.1 mole % and chlorine from about 0.001 to about 0.5 mole %.
  • the inclusion of chlorine and fluorine helps to dry the glass melt by reducing ⁇ - ⁇ . Additionally, the fluorine also acts as a refining agent.
  • the glass composition further comprises of at least one of the refining agents chosen from the group consisting of As 2 0 3 in the range from 0 to 0.7 mole % and Sb 2 0 3 in the range from 0 to 0.8 mole % along with N 2 0 5 in the range from about 0.1 to 0.4 mole%. It is observed that use of N2O5 in conjunction with AS2O3 and Sb 2 0 3 increases the refining efficiency of the refining agents.
  • the glass has a density of less than about 2.5 g/cm 3 , a coefficient of thermal expansion less than 45 x 10 "7 /°C, a logarithm of liquidus viscosity of greater than 5, a strain point of greater than 620 °C, an annealing temperature of about 650°C or greater, and a liquidus temperature of less than 1230 °C.
  • the glass is down- drawable or slot drawn or press-formable in a mold or drawable through roller press or drawable through float process.
  • the present invention is concerned with enhanced glasses for use as substrates in displays.
  • the glasses meet the various property requirements of such substrates.
  • the glass substrate composition comprises of the major components of the glass, for use in glass substrates, namely, Silica (Si0 2 ), Alumina (AI2O3), Boron Oxide (B2O3), trace amount of alkali oxides (AO) such as Na20 and alkaline earth oxides (AEO) such as CaO, SrO and BaO.
  • Silica Si0 2
  • Alumina AI2O3
  • Boron Oxide B2O3
  • trace amount of alkali oxides (AO) such as Na20
  • alkaline earth oxides (AEO) such as CaO, SrO and BaO.
  • silica behaves as the basic glass former, wherein the former (silica in this case) forms the basic skeleton or network.
  • Formers alone may form glass however the melting point in some cases (particularly when the former is silica) will be so high so as to make it impractical to commercially melt the glasses.
  • B2O3 or P2O5 is utilized as former the chemical durability will be so poor that it is impractical to use it in any application in its hundred percent forms.
  • modifiers such as alkali oxides (AO) and Alkaline earth oxides (AEO) are utilized to modify the network structure formed by the glass formers so as to reduce the melting temperature and thereby improve other glass forming processes e.g., refining.
  • alkali oxides such as Na 2 0 is utilized as the modifier for reasons discussed herein below.
  • alkaline earth oxides such as CaO, BaO and SrO are added as modifiers.
  • intermediates such as alumina is added to the glass composition.
  • the substrate glass composition comprises Si0 2 from about 63.3 to about 71.3 mole %; AI2O3 from about 8.1 to about 12.1 mole %; B 2 0 3 from about 6.7 to about 12.7 mole %; CaO from about 5 to 12 mole %; BaO from about 0.2 to about 3.0 mole %; SrO from about 0.2 to about 4.5 mole %; and Na 2 0 from about 0.001 to about 0.1 mole %; wherein inclusion of the trace amount of the alkali metal Na 2 0 decreases the melting point of the substrate glass composition; fluorine from about 0.001 to about 0.1 mole % and chlorine from about 0.001 to about 0.5 mole % resulting in drying the glass, hence reducing ⁇ - ⁇ , which thereby reduces foaming behavior of the glass.
  • the trace mole % of Na 2 0 is limited to a cap value of 0.1 mole % as a greater amount than this may lead to diffusion of sodium into the TFT which may interfere with the electrical working of the TFT. Presence of trace amount of Na 2 0 reduces the viscosity of glass melt, resulting in easier refining and reduced foaming.
  • the substrate glass composition may contain AS2O3 in the range from about 0 to about 0.7 mole %, wherein AS2O3 is acts as a fining agent and aids in removal of bubbles or gaseous inclusions from the molten glass.
  • the substrate glass composition may contain Sb 2 0 3 in the range from about 0 to about 0.8 mole %, wherein Sb 2 0 3 also acts as a fining agent and aids in removal of bubbles or gaseous inclusions from the molten glass.
  • the substrate glass composition may contain N2O5 in the range from about 0.1 to 0.4 mole % in conjunction with AS2O3 and Sb 2 03, wherein addition of N 2 0 5 enhances the refining efficiency of As 2 0 3 and Sb 2 0 3 .
  • the amount of As 2 0 3 and Sb 2 03 is maintained to a minimum level in the glass composition.
  • the alkaline earth oxides SrO and BaO both contribute to low liquidus temperatures (high liquidus viscosities) and hence the glasses of the invention include at least one of these oxides.
  • both oxides are known to raise the coefficient of thermal expansion (CTE) and density of the glass. It is desired to have both the CTE and density of the glasses to be low.
  • both SrO and BaO lowers the modulus and strain point of the glass in comparison with CaO.
  • the mole percentage of non-green components such as BaO and SrO is kept to a minimum so as to produce an environmentally friendly "green" product, and in particular lessening or getting rid of barium is preferred since barium is one of the listed metals in the Resources Conservation and Recovery Act (RCRA) and is therefore classified by the US EPA as hazardous.
  • RCRA Resources Conservation and Recovery Act
  • ⁇ - ⁇ value is used to indicate the hydroxyl concentration of a glass as measured in the conventional manner by infrared spectroscopy according to U.S. Pat. No. 4,072,489 (i.e., at an appropriate wave length of a few microns).
  • ⁇ - ⁇ value of 0.04 indicates a hydroxyl concentration of about 40 ppm.
  • hydroxyl ions are a part of the network structure. Chlorides react with hydroxyl ions to form Hydrogen Chloride gas, which escapes from the glass melt. This reaction of Chlorides helps to reduce the ⁇ - OH in glass, thereby resulting in an improved refining and reduced foaming of the glass melt.
  • the three components i.e., Na 2 0, F and CI individually assist in directly or indirectly assist in refining. But, their combination is more effective because of the combined multiplying effects of the individual components towards a common final process improvement, i.e., refining. If the same amount of effect (as it is obtained by the combined effect of the 3 components) is desired from any one component then the quantity of one single component will have to be very high and this will lead to other side effects, e.g., if Na 2 0 alone is added then the Na 2 0 contamination of TFT will happen. If F and CI alone are added then environmental hazard will be a problem. In accordance with the present invention an advantage of the glass from the glass composition is that it exhibit higher viscosity, typically of the order of 10 6 poise.
  • the glass from the glass composition exhibit a high-strain point greater than about 620 °C.
  • the glass from the glass composition has lower liquidus temperature of less than about 1230 °C.
  • the glass from the glass composition exhibits a high liquidus viscosity of about 10 5 or greater.
  • the glass from the glass composition exhibits an annealing temperature of greater than about 650 °C
  • the trace amount of Na 2 0 does not chemically interact with the TFTs due to very low percentages and but still reduce the melting point of the glass.
  • the substrate glass has light-weight owing to the low density of less than about 2.5 g/cm 3 . In accordance with the present invention, the substrate glass has lower coefficient of thermal expansion of less than about 40 x 10 "7 /°C
  • the present invention provides a glass composition for display devices compatible with the down draw fusion process.
  • the substrate glass composition may be used in liquid crystal display [LCD], an electroluminescence display [ELD], a field emission display [FED], plasma display [PD], organic light emitting diode display [OLED] etc.
  • LCD liquid crystal display
  • ELD electroluminescence display
  • FED field emission display
  • PD plasma display
  • OLED organic light emitting diode display
  • examples 1 to XXVIII are glass compositions in accordance with the embodiments of the present invention
  • C-I is a comparative example of glass composition in accordance with known prior art. It is observed that owing to presence of ⁇ - ⁇ in . C-I, there is foam formation at about 1420 °C, whereas due to drying effect of chlorine and fluorine, the value of ⁇ - ⁇ is expected to be reduced, whereas no foam formation was observed in examples I to XXVIII due to the drying and refining effect of chlorine and fluorine.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Glass Compositions (AREA)

Abstract

La présente invention concerne un substrat de verre et une composition de verre à β-ΟΗ réduit, à bulles ou inclusion réduites, la composition de verre comprenant Si02 entre environ 63,3 et environ 71,3 mole %; Al2O3 entre environ 8,1 et environ 12,1 mole %; B2O3 entre environ 6,7 et environ 12,7 mole %; CaO entre environ 5 et 12 mole %; BaO entre environ 0,2 et environ 3,0 mole %; SrO entre environ 0,2 et environ 4,5 mole %; et Na2O entre environ 0,001 et environ 0,1 mole %; l'inclusion de métal alcalin Na2 abaissant le point de fusion de la composition de substrat de verre; du fluor entre environ 0,001 et environ 0,1 mole % et du chlore entre environ 0,001 et environ 0,5 mole %, améliore le raffinage et réduit le moussage de verre.
PCT/IN2012/000343 2011-05-11 2012-05-11 Composition de verre et substrat de verre pour dispositifs d'affichage WO2012156991A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN1446MU2011 2011-05-11
IN1446/MUM/2011 2011-05-11

Publications (3)

Publication Number Publication Date
WO2012156991A2 true WO2012156991A2 (fr) 2012-11-22
WO2012156991A3 WO2012156991A3 (fr) 2013-02-21
WO2012156991A4 WO2012156991A4 (fr) 2013-04-11

Family

ID=47177405

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2012/000343 WO2012156991A2 (fr) 2011-05-11 2012-05-11 Composition de verre et substrat de verre pour dispositifs d'affichage

Country Status (1)

Country Link
WO (1) WO2012156991A2 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019055895A (ja) * 2017-09-21 2019-04-11 Ａｇｃ株式会社 ホウケイ酸ガラスおよびその製造方法
US11114472B2 (en) * 2018-12-20 2021-09-07 Samsung Display Co., Ltd. Thin film transistor panel, display device, and method of manufacturing the thin film transistor panel
WO2024139237A1 (fr) * 2022-12-28 2024-07-04 中建材玻璃新材料研究院集团有限公司 Verre à delo présentant de bonnes performances optiques

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01201043A (ja) * 1988-02-05 1989-08-14 Eta G K:Kk 高強度ガラス
CN1525945A (zh) * 2001-03-24 2004-09-01 Ф�ز������쳧 无碱铝硼硅酸盐玻璃及其用途
JP2007039316A (ja) * 2005-06-27 2007-02-15 Nippon Electric Glass Co Ltd ディスプレイ用ガラス基板
CN101213148A (zh) * 2005-07-06 2008-07-02 旭硝子株式会社 无碱玻璃的制造方法以及无碱玻璃板

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01201043A (ja) * 1988-02-05 1989-08-14 Eta G K:Kk 高強度ガラス
CN1525945A (zh) * 2001-03-24 2004-09-01 Ф�ز������쳧 无碱铝硼硅酸盐玻璃及其用途
JP2007039316A (ja) * 2005-06-27 2007-02-15 Nippon Electric Glass Co Ltd ディスプレイ用ガラス基板
CN101213148A (zh) * 2005-07-06 2008-07-02 旭硝子株式会社 无碱玻璃的制造方法以及无碱玻璃板

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019055895A (ja) * 2017-09-21 2019-04-11 Ａｇｃ株式会社 ホウケイ酸ガラスおよびその製造方法
US11114472B2 (en) * 2018-12-20 2021-09-07 Samsung Display Co., Ltd. Thin film transistor panel, display device, and method of manufacturing the thin film transistor panel
WO2024139237A1 (fr) * 2022-12-28 2024-07-04 中建材玻璃新材料研究院集团有限公司 Verre à delo présentant de bonnes performances optiques

Also Published As

Publication number Publication date
WO2012156991A3 (fr) 2013-02-21
WO2012156991A4 (fr) 2013-04-11

Similar Documents

Publication Publication Date Title
JP6365826B2 (ja) ガラス
TWI619686B (zh) 玻璃及玻璃基板
JP4941872B2 (ja) 液晶ディスプレイ用透明無アルカリガラス基板
WO2016143665A1 (fr) Substrat en verre
JP7421171B2 (ja) ガラス
JP2016528152A (ja) アルカリドープおよび無アルカリホウアルミノケイ酸ガラス
EP2349938A2 (fr) Verre à coefficient d expansion thermique intermédiaire
KR20140057474A (ko) 강화 커버 유리의 유리 조성물
JP6532218B2 (ja) ガラス
TW201305083A (zh) 平面顯示器用玻璃基板及其製造方法
JP7382014B2 (ja) ガラス板及びその製造方法
JP7307407B2 (ja) 無アルカリガラス
TWI838725B (zh) 玻璃
JP2012022200A (ja) ディスプレイ装置
CN109843817B (zh) 玻璃
WO2013154035A1 (fr) Plaque de verre
JP4613635B2 (ja) ガラス及びその製造方法
WO2012156991A2 (fr) Composition de verre et substrat de verre pour dispositifs d'affichage
CN105916821B (zh) 硅酸盐玻璃的制造方法、硅酸盐玻璃及硅酸盐玻璃用二氧化硅原料
TWI518045B (zh) 平板顯示器用玻璃基板
WO2012160572A2 (fr) Composition de verre et substrat en verre pour dispositifs d'affichage
JP6354943B2 (ja) ガラス
JP2015067523A (ja) ガラス基板の製造方法及びガラス基板製造装置
WO2018186143A1 (fr) Substrat en verre
JP6631942B2 (ja) 無アルカリガラス板

Legal Events

Date Code Title Description
NENP Non-entry into the national phase in:

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12785457

Country of ref document: EP

Kind code of ref document: A2