CN116648438A - Method for manufacturing alkali-free glass substrate - Google Patents
Method for manufacturing alkali-free glass substrate Download PDFInfo
- Publication number
- CN116648438A CN116648438A CN202180084882.2A CN202180084882A CN116648438A CN 116648438 A CN116648438 A CN 116648438A CN 202180084882 A CN202180084882 A CN 202180084882A CN 116648438 A CN116648438 A CN 116648438A
- Authority
- CN
- China
- Prior art keywords
- glass
- alkali
- glass substrate
- producing
- free glass
- Prior art date
- Legal status (The legal status 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 status listed.)
- Pending
Links
- 239000011521 glass Substances 0.000 title claims abstract description 199
- 239000000758 substrate Substances 0.000 title claims abstract description 48
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 46
- 238000000034 method Methods 0.000 title claims abstract description 38
- 239000002994 raw material Substances 0.000 claims abstract description 43
- 229910052751 metal Inorganic materials 0.000 claims abstract description 34
- 239000002184 metal Substances 0.000 claims abstract description 34
- 238000002844 melting Methods 0.000 claims abstract description 32
- 230000008018 melting Effects 0.000 claims abstract description 32
- 239000006060 molten glass Substances 0.000 claims abstract description 16
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims abstract description 11
- 229910004298 SiO 2 Inorganic materials 0.000 claims abstract description 10
- 238000003280 down draw process Methods 0.000 claims abstract description 10
- 150000003606 tin compounds Chemical class 0.000 claims abstract description 5
- 150000001463 antimony compounds Chemical class 0.000 claims abstract description 4
- 150000001495 arsenic compounds Chemical class 0.000 claims abstract description 4
- 239000006063 cullet Substances 0.000 claims description 25
- 239000000203 mixture Substances 0.000 claims description 11
- 230000005855 radiation Effects 0.000 claims description 7
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims description 6
- 229960002645 boric acid Drugs 0.000 claims description 6
- 235000010338 boric acid Nutrition 0.000 claims description 6
- 229910052796 boron Inorganic materials 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 claims description 5
- 239000006148 magnetic separator Substances 0.000 claims description 5
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 4
- 238000002485 combustion reaction Methods 0.000 claims description 4
- 230000001105 regulatory effect Effects 0.000 claims description 3
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 17
- 238000004031 devitrification Methods 0.000 description 16
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 12
- 239000007791 liquid phase Substances 0.000 description 11
- 239000000395 magnesium oxide Substances 0.000 description 11
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 11
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 11
- 238000007500 overflow downdraw method Methods 0.000 description 11
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 10
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 10
- 238000010438 heat treatment Methods 0.000 description 9
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 9
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 description 8
- 229910052742 iron Inorganic materials 0.000 description 8
- 239000011787 zinc oxide Substances 0.000 description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 229910001887 tin oxide Inorganic materials 0.000 description 7
- 238000002834 transmittance Methods 0.000 description 7
- 239000013078 crystal Substances 0.000 description 6
- 239000000156 glass melt Substances 0.000 description 6
- 229910052697 platinum Inorganic materials 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- DHEQXMRUPNDRPG-UHFFFAOYSA-N strontium nitrate Chemical compound [Sr+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O DHEQXMRUPNDRPG-UHFFFAOYSA-N 0.000 description 6
- 229910006404 SnO 2 Inorganic materials 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 5
- 229910000019 calcium carbonate Inorganic materials 0.000 description 5
- 150000002739 metals Chemical class 0.000 description 5
- 238000000465 moulding Methods 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 4
- 229910052787 antimony Inorganic materials 0.000 description 4
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 4
- 229910052785 arsenic Inorganic materials 0.000 description 4
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 238000005485 electric heating Methods 0.000 description 4
- BDAGIHXWWSANSR-NJFSPNSNSA-N hydroxyformaldehyde Chemical compound O[14CH]=O BDAGIHXWWSANSR-NJFSPNSNSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229910052750 molybdenum Inorganic materials 0.000 description 4
- 239000011733 molybdenum Substances 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910000018 strontium carbonate Inorganic materials 0.000 description 4
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 3
- 229910002651 NO3 Inorganic materials 0.000 description 3
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 3
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 description 3
- IWOUKMZUPDVPGQ-UHFFFAOYSA-N barium nitrate Chemical compound [Ba+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O IWOUKMZUPDVPGQ-UHFFFAOYSA-N 0.000 description 3
- JKWMSGQKBLHBQQ-UHFFFAOYSA-N diboron trioxide Chemical compound O=BOB=O JKWMSGQKBLHBQQ-UHFFFAOYSA-N 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 239000006025 fining agent Substances 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 2
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 description 2
- 229910001260 Pt alloy Inorganic materials 0.000 description 2
- 229910010413 TiO 2 Inorganic materials 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 229910000272 alkali metal oxide Inorganic materials 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910052661 anorthite Inorganic materials 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- GWWPLLOVYSCJIO-UHFFFAOYSA-N dialuminum;calcium;disilicate Chemical compound [Al+3].[Al+3].[Ca+2].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-] GWWPLLOVYSCJIO-UHFFFAOYSA-N 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 229910052733 gallium Inorganic materials 0.000 description 2
- 239000006066 glass batch Substances 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 229910052738 indium Inorganic materials 0.000 description 2
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 2
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 description 2
- 239000000347 magnesium hydroxide Substances 0.000 description 2
- 229910001862 magnesium hydroxide Inorganic materials 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000005191 phase separation Methods 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 239000004408 titanium dioxide Substances 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- 229910052845 zircon Inorganic materials 0.000 description 2
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 2
- 229910018068 Li 2 O Inorganic materials 0.000 description 1
- MXRIRQGCELJRSN-UHFFFAOYSA-N O.O.O.[Al] Chemical compound O.O.O.[Al] MXRIRQGCELJRSN-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 229910006501 ZrSiO Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- DHAHRLDIUIPTCJ-UHFFFAOYSA-K aluminium metaphosphate Chemical compound [Al+3].[O-]P(=O)=O.[O-]P(=O)=O.[O-]P(=O)=O DHAHRLDIUIPTCJ-UHFFFAOYSA-K 0.000 description 1
- 229910000323 aluminium silicate Inorganic materials 0.000 description 1
- MHCAFGMQMCSRGH-UHFFFAOYSA-N aluminum;hydrate Chemical compound O.[Al] MHCAFGMQMCSRGH-UHFFFAOYSA-N 0.000 description 1
- AYJRCSIUFZENHW-DEQYMQKBSA-L barium(2+);oxomethanediolate Chemical compound [Ba+2].[O-][14C]([O-])=O AYJRCSIUFZENHW-DEQYMQKBSA-L 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- XZTWHWHGBBCSMX-UHFFFAOYSA-J dimagnesium;phosphonato phosphate Chemical compound [Mg+2].[Mg+2].[O-]P([O-])(=O)OP([O-])([O-])=O XZTWHWHGBBCSMX-UHFFFAOYSA-J 0.000 description 1
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
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
- C03C3/083—Glass compositions containing silica with 40% to 90% silica, by weight containing aluminium oxide or an iron compound
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B1/00—Preparing the batches
- C03B1/02—Compacting the glass batches, e.g. pelletising
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B17/00—Forming molten glass by flowing-out, pushing-out, extruding or drawing downwardly or laterally from forming slits or by overflowing over lips
- C03B17/06—Forming glass sheets
- C03B17/064—Forming glass sheets by the overflow downdraw fusion process; Isopipes therefor
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B3/00—Charging the melting furnaces
- C03B3/02—Charging the melting furnaces combined with preheating, premelting or pretreating the glass-making ingredients, pellets or cullet
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/02—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating
- C03B5/027—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating by passing an electric current between electrodes immersed in the glass bath, i.e. by direct resistance heating
-
- 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
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
-
- 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
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
- C03C1/02—Pretreated ingredients
- C03C1/024—Chemical treatment of cullet or glass fibres
-
- 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
- C03C3/089—Glass compositions containing silica with 40% to 90% silica, by weight containing boron
- C03C3/091—Glass compositions containing silica with 40% to 90% silica, by weight containing boron containing aluminium
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
- Y02P40/57—Improving the yield, e-g- reduction of reject rates
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Electrochemistry (AREA)
- Glass Compositions (AREA)
- Glass Melting And Manufacturing (AREA)
Abstract
The invention provides a method for manufacturing an alkali-free glass substrate, which can manufacture an alkali-free glass substrate with few pits. Is continuously producing SiO 2 ‑Al 2 O 3 -a method of RO (RO is one or more of MgO, caO, baO, srO and ZnO) based alkali-free glass substrate, wherein the method comprises: a step of preparing a raw material batch so as to contain a tin compound and substantially contain no arsenic compound and no antimony compound; a step of electrically melting the prepared raw material batch in a melting furnace capable of being electrically heated by means of electrodes; and forming the molten glass into a plate shape by a down-draw method, wherein the glass has a beta-OH value of 0.05/mm or more and a metal pit number of 20/ton or less.
Description
Technical Field
The present invention relates to a method for producing an alkali-free glass substrate, and more particularly, to a method for producing an alkali-free glass substrate suitable for a display or the like including a thin film transistor (TFT: thin Film Transistor) having an oxide film such as indium gallium zinc oxide (Indium Gallium Zinc Oxide, IGZO).
Background
In flat panel displays, a glass substrate is generally used as a support substrate. A circuit pattern such as a TFT is formed on the surface of the glass substrate. Therefore, in order to prevent adverse effects on TFTs and the like, an alkali-free glass substrate containing substantially no alkali metal component is used as such a glass substrate.
As a method for forming an alkali-free glass substrate, a downdraw method typified by an overflow downdraw method and the like are known.
The downdraw method is a method of drawing molten glass downward to form a plate shape. An overflow downdraw method, which is one of the downdraw methods, is a method of forming a glass ribbon by downwardly stretching molten glass that overflows from both sides of a forming body (forming body) having a substantially wedge-shaped cross section. Molten glass overflowed from both sides of the forming body flows down both side surfaces of the forming body and merges under the forming body. Therefore, in the overflow downdraw method, the surface of the glass ribbon is formed by the surface tension without being in contact with the air, and therefore, even if the surface is not polished after molding, a glass substrate having a flat surface without foreign matter adhering to the surface can be obtained. In addition, there is an advantage that a thin glass substrate can be easily formed by the overflow down-draw method.
Further, as a melting method of the alkali-free glass substrate, there is an electric melting method described in patent document 1.
Prior art literature
Patent literature
Patent document 1: japanese patent application laid-open No. 2014-88306
Disclosure of Invention
Technical problem to be solved by the invention
However, the glass described in patent document 1 has a problem that pitting is likely to occur.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for producing an alkali-free glass substrate having a small number of pits.
Means for solving the problems
The method for producing alkali-free glass of the present invention is continuous production of SiO 2 -Al 2 O 3 A method for producing an alkali-free glass substrate of RO (RO is one or more of MgO, caO, baO, srO and ZnO) system, comprising: a step of preparing a raw material batch so as to contain a tin compound and substantially contain no arsenic compound and no antimony compound; a step of electrically melting the prepared raw material batch in a melting furnace capable of being electrically heated by means of electrodes; and forming the molten glass into a plate shape by a down-draw method, wherein the glass has a beta-OH value of 0.05/mm or more and a metal pit number of 20/ton or less. The term "metal pits" as used herein means the number of metal pits per 1 ton of glass calculated from the size of glass used for measurement when the metal pits are observed by a solid microscope and counted when the metal pits of 1 μm or more are observed in an observation field.
As a result of various studies, the present inventors have found that when glass is electrically melted, snO in the glass is represented by formula 1 (x and y are coefficients, M represents Fe, cr and/or Ni) 2 The Sn-containing metal pits are precipitated in the glass by reduction of Fe, cr, ni, etc. contained in the raw material batch. It has further been found that by increasing the beta-OH value of the glass, the glass is obtained by the method of the formula 2 (wherein z is a coefficient, and M represents Fe, cr and/or Ni), fe, cr, ni, etc., andOH groups in the glass combine and thus it becomes difficult to combine SnO 2 Reduction, the metal pits are not easy to be precipitated in the glass.
(1)
(2)
"alkali-free glass" means glass to which an alkali metal oxide component is not intentionally added, specifically, alkali metal oxide (Li 2 O、Na 2 O, K 2 And the content of O) is 2000ppm (mass) or less. "continuously producing" means continuously producing glass in a continuous melting furnace such as a tank furnace for a fixed period of time. So-called "SiO 2 -Al 2 O 3 By RO-system is meant that the reaction of SiO 2 、Al 2 O 3 And RO' as an essential component. "electric melting" refers to a melting method in which electric current is applied to glass, and the glass is melted by using joule heat generated by the electric current. Here, a melting method using radiation heating by a heater or a burner is not excluded. By "substantially free of arsenic and antimony" is meant that the glass raw materials, glass cullet, comprising these components are not intentionally added to the glass batch. More specifically, it means that arsenic is expressed As in terms of mole in the obtained glass 2 O 3 Less than 50ppm of antimony as Sb 2 O 3 Is 50ppm or less. The "downdraw method" is a generic term for a forming method in which molten glass is continuously drawn downward and formed.
The present invention is also characterized in that the glass is melted by electric heating. When the electric heating is used, the energy per unit mass for obtaining the molten glass is reduced, and thus the environmental load can be reduced.
In the present invention, the β -OH value and the number of metal pits of the obtained glass are preferably adjusted by using the glass raw material and/or the melting conditions.
In the present invention, the effect becomes more remarkable without using radiation heating by combustion of a burner. "without using the radiation heating by the burner combustion" means that the radiation heating by the burner combustion is not performed at all at the time of ordinary production, and the use of the burner at the time of production start-up (at the time of temperature rise) is not excluded. In addition, it is not excluded to use radiation heating by a heater at the start-up of production, at the time of normal production. The term "production start-up" refers to a period of time until the raw material batch is dissolved and becomes a glass melt, and electric heating is possible.
In the present invention, B is also contained in the production 2 O 3 In the case of an alkali-free glass substrate having a glass composition, orthoboric acid is preferably used as at least a part of a glass raw material serving as a boron source.
With the above configuration, the moisture content of the obtained glass can be easily adjusted. In addition, boron component (B) 2 O 3 ) Since the glass is a component that improves the meltability of the glass, the use of the above-described structure makes it easy to obtain glass with excellent productivity.
In the present invention, it is preferable to include a hydroxide raw material in the raw material batch.
In the present invention, when glass cullet is added to a raw material batch to produce an alkali-free glass substrate, it is preferable to use glass cullet containing glass having a β -OH value of 0.05/mm or more as at least a part of the glass cullet. The term "glass cullet" as used herein refers to defective glass produced during glass production, recycled glass recovered from the market, or the like. The "β -OH value" is a value obtained by measuring the transmittance of glass by FT-IR and using the following formula.
beta-OH value= (1/X) log (T 1 /T 2 )
X: glass wall thickness (mm)
T 1 : reference wavelength 3846cm -1 Transmittance at (percent)
T 2 : hydroxyl absorption wavelength 3600cm -1 Minimum transmittance in the vicinity (%)
In the present invention, the step of removing metal by passing the glass cullet through the magnetic separator is preferably performed 2 or more times.
Metals including Fe, cr, ni, and the like used in blending facilities and the like are mixed into the recycled glass cullet. By passing the glass cullet through the magnetic separator twice or more, metals including Fe, cr, ni, and the like can be sufficiently removed, and it is difficult to mix metals including Fe, cr, ni, and the like into the raw material batch. As a result, sn-containing metal pits are difficult to deposit in the glass.
In the present invention, the strain point of the obtained glass is preferably 690℃or higher. Here, the "strain point" is a value measured based on the method of ASTM C336-71.
In the present invention, the heat shrinkage of the obtained glass is preferably 25ppm or less. The term "heat shrinkage" as used herein refers to a value obtained when glass is heated from normal temperature to 500 ℃ at a rate of 5 ℃/min, kept at 500 ℃ for 1 hour, and then measured while being cooled at a rate of 5 ℃/min.
The heat shrinkage was measured by the following method. First, as shown in FIG. 1 (a), a 160mm X30 mm bar-shaped sample G was prepared as a sample of the glass plate 1. The water-resistant abrasive paper #1000 was used at each of the two longitudinal ends of the bar-shaped sample G, and the mark M was formed at a position 20 to 40mm from the edge. Thereafter, as shown in fig. 1 (b), the bar-shaped sample G on which the mark M is formed is folded into 2 pieces in a direction orthogonal to the mark M, and sample pieces Ga and Gb are produced. Then, only one sample piece Gb was subjected to heat treatment in which the temperature was raised from room temperature (25 ℃) to 500 ℃ at 5 ℃/min, and the temperature was lowered to room temperature at 5 ℃/min after holding at 500 ℃ for 1 hour. After the heat treatment, as shown in fig. 1 (c), the sample pieces Ga and Gb which have not been heat-treated were arranged in parallel, and the positional shift amounts (Δl) of the marks M of the 2 sample pieces Ga and Gb were read by a laser microscope 1 、ΔL 2 ) The heat shrinkage was calculated by the following formula. Wherein l in the formula 0 Is the initial distance between the marks M.
Heat shrinkage = [ { Δl 1 (μm)+ΔL 2 (μm)}×10 3 ]/l 0 (mm)(ppm)
With the above structure, a glass substrate suitable for forming an oxide TFT can be obtained.
In the present invention, it is preferable to use the oxide TFT-forming glass substrate in the production of the glass substrate.
Drawings
Fig. 1 is a plan view for explaining a measurement step of the heat shrinkage of a glass substrate.
Fig. 2 is a graph showing the relationship of β -OH value to metal pitting.
Detailed Description
The method for producing alkali-free glass of the present invention will be described in detail below.
The method of the invention comprises the following steps: a step of preparing a raw material batch; a step of electrically melting the prepared batch; and forming the molten glass into a plate shape.
(1) Procedure for preparing raw batch materials
First, to become SiO 2 -Al 2 O 3 The glass raw material was prepared in such a manner that the composition of RO (RO is one or more of MgO, caO, baO, srO and ZnO) system was used. The preferred glass composition will be described later.
As the silicon source, silica sand, stone powder (SiO 2 ) Etc.
As the aluminum source, alumina (Al 2 O 3 ) Aluminum hydroxide (Al (OH) 3 ) Etc.
As the boron source, orthoboric acid (H) 3 BO 3 ) Boric anhydride (B) 2 O 3 ). Since orthoboric acid contains crystal water, the water content of the glass can be adjusted to be high when the use ratio is large. Therefore, it is preferable to use both orthoboric acid and boric anhydride, and the use ratio thereof is adjusted according to the targeted β -OH content.
The alkaline earth metal source may be calcium carbonate (CaCO) 3 ) Magnesium oxide (MgO), magnesium hydroxide (Mg (OH) 2 ) Barium carbonate (BaCO) 3 ) Barium nitrate (Ba (NO) 3 ) 2 ) Strontium carbonate (SrCO) 3 ) Strontium nitrate (Sr (NO) 3 ) 2 ) Etc.
As the zinc source, zinc oxide (ZnO) or the like can be used.
As a zirconia source, zircon (ZrSiO 4 ) Etc. When a Zr-containing refractory such as zirconia electroformed refractory or dense zircon (dense zirconia) is used as the refractory constituting the melting furnace, there is a case where the zirconia component from the refractory is eluted. These eluted components can also be used as a zirconia source.
As the titanium source, titanium oxide (TiO 2 ) Etc.
As the phosphorus source, aluminum metaphosphate (Al (PO) 3 ) 3 ) Magnesium pyrophosphate (Mg) 2 P 2 O 7 ) Etc.
As the tin compound, tin oxide (SnO 2 ) Etc. In the case of using tin oxide, it is preferable to use the average particle diameter D 50 Tin oxide in the range of 0.3 to 50. Mu.m, 2 to 50. Mu.m, particularly 5 to 50. Mu.m. If the average particle diameter D of the tin oxide powder 50 If the particles are small, agglomeration between particles is caused, and clogging is likely to occur in the blending equipment. On the other hand, if the average particle diameter D of the tin oxide powder 50 If the amount of the tin oxide powder is large, the dissolution reaction of the tin oxide powder into the glass melt is delayed, and the melt cannot be clarified. As a result, oxygen cannot be sufficiently released at a proper time of glass melting, bubbles tend to remain in the glass product, and it is difficult to obtain a product excellent in bubble quality. In addition, snO is easily caused to occur in glass products 2 Crystalline undissolved pock.
In the present invention, the carbonate raw material may be contained in the raw material batch. The carbonate raw material can make SnO as a fining agent 2 Effectively functions. As the carbonate raw material, for example, calcium carbonate (CaCO) can be used 3 ) Barium carbonate (BaCO) 3 ) Strontium carbonate (SrCO) 3 ) Etc.
In the present invention, the nitrate raw material may be contained in the raw material batch. Nitrate raw material can make SnO as clarifier 2 Effectively functions. As the nitrate raw material, for example, barium nitrate (Ba (NO 3 ) 2 ) Strontium nitrate (Sr (NO) 3 ) 2 ) Etc.
In the present invention, the hydroxide raw material may be contained in the raw material batch. The hydroxide raw material can increase the moisture content in the glass. As the hydroxide raw material, aluminum hydroxide (Al (OH)) can be used 3 ) Magnesium hydroxide (Mg (OH) 2 ) Calcium hydroxide (Ca (OH) 2 ) Etc.
In the present invention, it is preferable that the arsenic compound and the antimony compound are substantially not contained in the batch. If these components are contained, electrodes are corroded, and it is difficult to stably perform electric melting for a long period of time. In addition, these components are not preferable from an environmental point of view.
In the present invention, glass cullet is preferably used in addition to the above glass raw materials. When the glass cullet is used, the ratio of the glass cullet to the total amount of the raw material batch is preferably 1 mass% or more and 5 mass% or more, and particularly preferably 10 mass% or more. The upper limit of the ratio of the glass cullet to be used is not limited, but is preferably 50 mass% or less and 40 mass% or less, particularly preferably 30 mass% or less. It is preferable that at least a part of the glass cullet to be used is glass cullet composed of glass having a β -OH value of 0.05/mm or more, 0.07/mm or more, particularly 0.1/mm or more. If the beta-OH value of the glass cullet is too high, the strain point of the glass may be excessively lowered, and therefore the upper limit value of the beta-OH value of the glass cullet is preferably 0.4/mm or less.
The step of removing the metal by passing the glass cullet through the magnetic separator is performed 2 times or more, preferably 3 times or more, and particularly preferably 5 times or more. Thus, snO in the glass 2 Reduced metals including Fe, cr, ni, etc. are difficult to mix into the raw batch. As a result, sn-containing metal pits are less likely to precipitate. When the number of the steps is increased, the amount of metal including Fe, cr, ni, and the like mixed is reduced, but the number of the steps is preferably 10 or less from the viewpoint of cost.
(2) Process for electrofusion of raw material batch
Next, the prepared raw material batch was charged into a melting furnace, and electric melting was performed.
The melting furnace has a plurality of electrodes, and is energized between the electrodes to energize the glass melt, whereby the glass is continuously melted by the joule heat. The radiation heating by a heater or a burner may be used in combination with assistance.
The degree of freedom in arrangement and shape of the electrodes is high, and even alkali-free glass which is difficult to be energized can be used with an optimal electrode arrangement and shape, and molybdenum electrodes are preferably used as the electrodes in order to facilitate energization and heating. The electrode shape is preferably a rod shape. In the case of the rod shape, a desired electrode pitch can be maintained at any position on the side wall surface and the bottom wall surface of the melting furnace, and a desired number of electrodes can be arranged. The electrodes are preferably arranged in a plurality of pairs by shortening the inter-electrode distance on the wall surface (side wall surface, bottom wall surface, etc.), particularly the bottom wall surface, of the melting furnace. In the case where the glass contains an arsenic component and an antimony component, the molybdenum electrode is corroded, and therefore, it is not possible to use the electrode, and instead, it is necessary to use a tin electrode which is not corroded by these components. However, since the degree of freedom in the arrangement place of the tin electrode and the shape of the electrode is very low, it is difficult to electrically melt the alkali-free glass.
The raw material batch charged into the melting furnace is melted by electric heating to form a glass melt (molten glass). At this time, the tin compound contained in the raw material batch is dissolved in the glass melt and functions as a fining agent. In detail, the tin component releases oxygen bubbles during the temperature rising process. The released oxygen bubbles expand and float bubbles contained in the glass melt, and are removed from the glass. In addition, the tin component absorbs oxygen bubbles during the cooling process, thereby eliminating bubbles remaining in the glass.
The glass melted in the melting furnace is supplied to the forming apparatus, but a clearing tank, a stirring tank, a state adjusting tank, and the like may be disposed between the melting furnace and the forming apparatus, and supplied to the forming apparatus after passing through them. In order to prevent glass contamination, it is preferable that a communication flow path connecting the melting furnace and the forming device (or each of the grooves provided therebetween) is made of platinum or a platinum alloy at least on a contact surface with the glass.
(3) A step of shaping the molten glass into a plate shape
Next, the glass melted in the melting furnace is supplied to a forming apparatus, and formed into a plate shape by a downdraw method.
As the downdraw method, an overflow downdraw method is preferably employed. The overflow downdraw method is a method of forming glass into a plate shape by overflowing molten glass from both sides of a trough-shaped refractory having a wedge-shaped cross section, joining the overflowed molten glass at the lower end of the trough-shaped refractory, and simultaneously extending the glass downward. In the overflow downdraw method, a surface to be a surface of a glass substrate is formed in a free surface state without being in contact with a groove-like refractory. Therefore, a glass substrate having excellent surface quality without polishing can be manufactured at low cost, and the size and thickness of glass can be easily increased. The structure and material of the trough-like refractory used in the overflow downdraw method are not particularly limited as long as the desired size and surface accuracy can be achieved. In addition, the method of applying the force in the downward extension molding is not particularly limited. For example, a method of stretching a glass by rotating a heat-resistant roller having a sufficiently large width in contact with the glass may be employed, or a method of stretching a glass by bringing a plurality of pairs of heat-resistant rollers into contact with only the vicinity of the end face of the glass may be employed. In addition to the overflow downdraw method, for example, a slit downdraw method or the like may be used.
The glass thus formed into a plate shape is cut into a predetermined size, and various kinds of chemical or mechanical processing are performed as needed, thereby forming a glass substrate.
(4) Composition of alkali-free glass
As a composition of alkali-free glass to which the production method of the present invention is suitably applicable, there can be exemplified a glass in which: the composition comprises the following components in percentage by mass: siO (SiO) 2 50～70％、Al 2 O 3 15～25％、B 2 O 3 2～7.5％、MgO 0～10％、CaO 0～10％、SrO 0～10％、BaO 0～15％、ZnO 0～5％、ZrO 2 0～1％、TiO 2 0～5％、P 2 O 5 0～10％、SnO 2 0.1 to 0.5% and substantially free of As 2 O 3 And Sb (Sb) 2 O 3 . The reason why the content of each component is limited as described above is shown below. In the explanation of the content of each component, the expression of% represents% by mass unless otherwise specified.
SiO 2 Is a component forming the skeleton of glass. SiO (SiO) 2 The lower limit of the content of (2) is preferably 50%, 51%, 51.5%, 52%, 55%, 56%, 57%, particularly preferably 58%. In addition, siO 2 The upper limit of the content of (c) is preferably 70%, 69%, 68%, 67%, 66%, 65%, 64%, 63%, particularly preferably 62%. If SiO is 2 If the content of (2) is too small, the density becomes too high and the acid resistance tends to be lowered. On the other hand, if SiO 2 If the content of (2) is too large, the high-temperature viscosity becomes high and the meltability tends to be low. In addition, devitrified crystals such as cristobalite are likely to precipitate, and the liquid phase temperature tends to rise.
Al 2 O 3 The component forming the skeleton of the glass, the component increasing the strain point and Young's modulus, and the component suppressing the phase separation. Al (Al) 2 O 3 The lower limit of the content of (2) is preferably 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, particularly preferably 18%. In addition, al 2 O 3 The upper limit of the content of (2) is preferably 25%, 24%, 23%, 22%, 21.5%, and particularly preferably 21%. If Al is 2 O 3 If the content of (C) is too small, the strain point and Young's modulus tend to be lowered, and the glass tends to be separated. On the other hand, if Al 2 O 3 If the content of (a) is too large, devitrified crystals such as mullite and anorthite are likely to be precipitated, and the liquid phase temperature tends to be increased.
B 2 O 3 Is a component that improves the meltability and improves the devitrification resistance. B (B) 2 O 3 The lower limit of the content of (2%) is preferably 2%, 2.2%, particularly preferably 2.5%. In addition, B 2 O 3 The upper limit of the content of (2) is preferably 7.5%, particularly preferably 7%. If B 2 O 3 If the content of (C) is too small, the melting property and resistance to devitrification are liable to be lowered, and the resistance to a hydrofluoric acid-based chemical such as buffered hydrofluoric acid is liable to be lowered. In addition, the amount of moisture carried in from the batch material may become too small. On the other hand, if B 2 O 3 If the content of (B) is too large, the strain point and Young's modulus tend to be lowered.
MgO is a component that reduces high-temperature tackiness and improves meltability, and among alkaline earth oxides, mgO is a component that significantly improves Young's modulus. The lower limit of the MgO content is preferably 0%, 0.1%, 0.5%, 1%, 1.5%, and particularly preferably 2%. The upper limit of the MgO content is preferably 10%, 9%, 8%, 7.5%, 7%, 6%, and particularly preferably 5%. If the MgO content is too small, the melting property and Young's modulus tend to be lowered. On the other hand, if the MgO content is too large, the devitrification resistance tends to be low, and the strain point tends to be low.
CaO is a component that does not lower the strain point, reduces the high-temperature viscosity, and significantly improves the meltability. In addition, since the raw materials are introduced into the alkaline earth metal oxide at relatively low cost, the alkaline earth metal oxide is a component that reduces the cost of the raw materials. The lower limit of the CaO content is preferably 0%, 0.1%, 1%, 2%, 3%, and particularly preferably 3.5%. The upper limit of the CaO content is preferably 10%, 9%, 8%, and particularly preferably 7%. If the CaO content is too small, the above-mentioned effects are hardly obtained. On the other hand, if the CaO content is too large, the glass tends to devitrify, and the coefficient of thermal expansion tends to increase.
SrO is a component that suppresses phase separation and improves resistance to devitrification. Further, the composition is a component which reduces the high-temperature viscosity and improves the meltability without lowering the strain point. Or a component that suppresses an increase in the liquid phase temperature. The lower limit of the content of SrO is preferably 0%, 0.1%, particularly preferably 0.3%. The upper limit of the content of SrO is preferably 10%, 9%, 8%, 7%, 6%, and particularly preferably 5%. When the SrO content is too small, the above effect is hardly obtained. On the other hand, when the content of SrO is too large, the density becomes too high, and devitrification crystals containing SrO are likely to precipitate, and the devitrification resistance is likely to decrease.
BaO is a component that significantly improves the devitrification resistance. The lower limit of the content of BaO is preferably 0%, 0.1% and 0.5%, particularly preferably 1%. The upper limit of the content of BaO is preferably 15%, 14%, 13%, 12%, 11%, and particularly preferably 10.5%. Too small a content of BaO makes it difficult to obtain the above-mentioned effects. On the other hand, when the content of BaO is too large, the density becomes too high and the meltability tends to be lowered. In addition, the devitrification crystal containing BaO is likely to precipitate, and the liquid phase temperature is likely to rise.
ZnO is a component for improving the meltability. The content of ZnO is preferably 0 to 5%, 0 to 4%, 0 to 3%, particularly preferably 0 to 2%. If the ZnO content is too high, the glass tends to devitrify, and the strain point tends to decrease.
ZrO 2 Is a component for improving chemical durability. ZrO (ZrO) 2 The lower limit of the content of (2) is preferably 0%, particularly preferably 0.01%. In addition, zrO 2 The upper limit of the content of (2) is preferably 1%, 0.5%, 0.2%, 0.1%, particularly preferably 0.05%. If ZrO 2 If the content of (B) is too large, zrSiO is liable to be produced 4 Is not in contact with the glass.
TiO 2 Is a component for reducing high-temperature viscosity and improving meltability. In addition, it is an ingredient for suppressing solarization. TiO (titanium dioxide) 2 The content of (2) is preferably 0 to 5%, 0 to 4%, 0 to 3%, 0 to 2%, 0 to 1%, particularly preferably 0 to 0.1%. TiO (titanium dioxide) 2 When the content of (b) is too large, the glass is colored, and the transmittance tends to be low.
P 2 O 5 The component for increasing the strain point is a component capable of suppressing devitrification and crystallization of an alkaline earth aluminosilicate such as anorthite. P (P) 2 O 5 The content is preferably 0 to 10%, 0 to 9%, 0 to 8%, 0 to 7%, 0 to 6%, 0 to 5%, 0 to 4%, particularly preferably 0 to 3%. If P 2 O 5 If the content of (2) is too large, the glass tends to separate phases.
SnO 2 Is a component having a good clarifying effect in a high temperature region, is a component for increasing a strain point, and is a component for reducing high temperature tackiness. In addition, there is an advantage in that the molybdenum electrode is not eroded. SnO (SnO) 2 The lower limit of the content of (2) is preferably 0.1%, particularly preferably 0.15%. In addition, snO 2 The upper limit of the content of (c) is preferably 0.5%, 0.45%, 0.4%, 0.35%, particularly preferably 0.3%. SnO (SnO) 2 When the content of (b) is too small, it is difficult to enjoy the above effects.On the other hand, snO 2 When the content of (C) is too large, snO 2 Is liable to precipitate and to promote ZrO 2 Is devitrified and crystallized.
From the viewpoint of environmental aspects and prevention of electrode erosion, it is preferable that As is substantially not contained 2 O 3 、Sb 2 O 3 . As used herein, "substantially free" means that no glass raw materials or glass cullet containing these components are intentionally added to the glass batch material. More specifically, in the obtained glass, arsenic is contained As 2 O 3 Less than 50ppm of antimony as Sb 2 O 3 Is 50ppm or less. These components are useful as fining agents, but should not be used because they attack the molybdenum electrode and make electrofusion difficult on an industrial scale. In addition, it is also preferable not to use it from the viewpoint of environment.
In addition to the above components, other components may be contained in an amount of 5% or less by total amount.
The glass may contain Cl and F, but the Cl content is preferably less than 0.1%, particularly preferably less than 0.05%, and the F content is preferably less than 0.1%, particularly preferably less than 0.05%. In addition, cl+F (total of Cl and F) is preferably less than 0.1%.
(5) Characteristics of alkali-free glass substrate, etc
Next, an alkali-free glass substrate obtained by the method of the present invention will be described.
The alkali-free glass substrate obtained by the method of the present invention comprises a glass having a beta-OH value of 0.05/mm or more, 0.07/mm or more, 0.1/mm or more, 0.12/mm or more, 0.15/mm or more, 0.18/mm or more, particularly 0.2/mm or more. Thus, the number of metal pits can be sufficiently reduced. When the β -OH value is too large, the strain point of the glass does not become sufficiently high, and it is difficult to reduce the heat shrinkage, so that the upper limit of the β -OH value is preferably 0.4/mm or less, particularly preferably 0.35/mm or less.
The alkali-free glass substrate obtained by the method of the present invention contains glass having a metal pit count of 20 or less per ton, 10 or less per ton, 5 or less per ton, and particularly 3 or less per ton. The lower limit of the metal pit is not particularly limited, but is practically 0.1/ton or more.
The alkali-free glass sheet obtained by the method of the present invention preferably has a heat shrinkage of 25ppm or less, 20ppm or less, 19ppm or less, 18ppm or less, 17ppm or less, 16ppm or less, 15ppm or less, and 14ppm or less, and particularly preferably 13ppm or less when the glass is heated from normal temperature to 500 ℃ at a rate of 5 ℃/minute and then kept at 500 ℃ for 1 hour and then cooled at a rate of 5 ℃/minute. If the heat shrinkage is large, it is difficult to use the film as a substrate for forming an oxide TFT. The lower limit of the heat shrinkage is not limited, but is preferably 2ppm or more, and particularly preferably 3ppm or more.
The alkali-free glass sheet obtained by the method of the present invention preferably contains a glass having a strain point of 690℃or higher, 700℃or higher, 705℃or higher, particularly 710℃or higher. In this way, in the manufacturing process of the oxide TFT, the thermal shrinkage of the glass plate is easily suppressed. When the strain point is too high, the temperature at the time of molding and dissolution becomes too high, and the production cost of the glass sheet tends to increase, so that the upper limit of the strain point is preferably 750 ℃ or less and 740 ℃ or less, particularly preferably 730 ℃ or less.
The alkali-free glass sheet obtained by the process of the present invention preferably comprises 10 2.5 The dPa.s temperature is 1630 ℃ or lower, 1620 ℃ or lower, 1610 ℃ or lower, 1600 ℃ or lower, 1590 ℃ or lower, particularly 1580 ℃ or lower. 10 2.5 When the temperature at dPa.s is too high, the glass becomes difficult to dissolve, the production cost of the glass plate is high, and defects such as bubbles are likely to occur. 10 2.5 When the temperature at dPa.s is too low, it is difficult to design the viscosity at the liquid phase temperature to be high, so that 10 2.5 The lower temperature limit at dPa.s is preferably 1500℃or higher and 1510℃or higher, particularly 1520℃or higher. "AND 10 2.5 The "temperature equivalent to dPa.s" is a value measured by the platinum ball pulling method.
The alkali-free glass sheet obtained by the process of the present invention preferably comprises glass having a liquidus temperature of less than 1250 ℃, less than 1240 ℃, less than 1230 ℃, less than 1220 ℃, less than 1210 ℃, particularly less than 1200 ℃. Thus, devitrification and crystallization are not easily generated during the production of glass, and the reduction of productivity is easily prevented. Further, since the glass sheet is easily formed by the overflow down-draw method, the surface quality of the glass sheet is easily improved, and the manufacturing cost of the glass sheet can be reduced. In addition, from the viewpoint of recent increases in the size of glass sheets and high definition of displays, there is a great interest in improving the devitrification resistance in order to suppress devitrification, which is a possibility of surface defects, as much as possible. The lower the liquid phase temperature is an index of the devitrification resistance, the more excellent the devitrification resistance is. The "liquid phase temperature" means a temperature at which glass powder passing through a standard sieve of 30 mesh (500 μm) and remaining in a sieve of 50 mesh (300 μm) is put into a platinum boat, held for 24 hours in a temperature gradient furnace set to 1100 ℃ to 1350 ℃, and then the platinum boat is taken out, and devitrification (crystal foreign matter) is confirmed in the glass.
The alkali-free glass sheet obtained by the process of the present invention preferably comprises a liquid phase viscosity of 10 4.0 dPa.s or more, 10 4.2 dPa.s or more, 10 4.4 dPa.s or more, 10 4.5 dPa.s or more, 10 4.6 dPa.s or more, 10 4.7 dPa.s or more, 10 4.8 dPa.s or more, 10 4.9 dPa.s or more, especially 10 5.0 dPa.s or more. In this way, devitrification is less likely to occur during forming, and hence, a glass sheet is easily formed by the overflow downdraw method, and as a result, the surface quality of the glass sheet can be improved, and the manufacturing cost of the glass sheet can be reduced. The higher the liquid phase viscosity is an index of formability, the higher the formability is. The "liquid phase viscosity" refers to the viscosity of glass at the liquid phase temperature, and can be measured by, for example, the platinum ball pulling method.
The substrate area of the alkali-free glass sheet obtained by the method of the present invention is preferably 4m 2 The above. If the substrate area is too small, it is difficult to efficiently manufacture a large LCD or OLED display having a TFT including an oxide film such as IGZO.
Examples
Next, the glass manufactured by the method of the present invention will be described. Table 1 shows examples (Nos. 1 to 6) of the present invention.
TABLE 1
| Mass percent of | No.1 | No.2 | No.3 | No.4 | No.5 | No.6 |
| SiO 2 | 61.5 | 62.0 | 60.0 | 60.3 | 59.2 | 59.1 |
| Al 2 O 3 | 19.0 | 20.0 | 19.0 | 20.0 | 19.0 | 18.0 |
| B 2 O 3 | 2.0 | 2.3 | 3.0 | 4.0 | 6.0 | 7.0 |
| MgO | 5.5 | 2.6 | 3.0 | 3.5 | 2.5 | 3.0 |
| CaO | 4.5 | 4.5 | 5.0 | 5.5 | 6.5 | 6.0 |
| SrO | 5.2 | 1.5 | 1.0 | 2.5 | 1.0 | 2.0 |
| BaO | 2.2 | 6.9 | 8.8 | 4.0 | 5.5 | 4.8 |
| SnO 2 | 0.1 | 0.15 | 0.2 | 0.2 | 0.25 | 0.15 |
| beta-OH value [/mm] | 0.12 | 0.15 | 0.25 | 0.28 | 0.30 | 0.33 |
| Metal pock (per ton) | 13.8 | 6 | 1.8 | 1 | 0.3 | 0.3 |
First, silica sand, alumina, orthoboric acid, boric anhydride, calcium carbonate, strontium nitrate, barium carbonate, and tin dioxide were mixed so as to have the compositions shown in table 1, and blended. In addition, glass cullet having the same composition as the target composition (β -OH value of 0.2/mm, 35 mass% relative to the total amount of the raw material batch) was used in combination. The glass cullet was subjected to a step of passing the glass cullet through a magnetic separator twice to remove metals.
Then, the glass raw material is supplied to an electric melting furnace not burning by a burner to be melted, and then the molten glass is clarified and homogenized in a clarifier or a regulating tank to be regulated to a viscosity suitable for molding.
Then, the molten glass was supplied to an overflow downdraw molding apparatus, molded into a plate shape, and then cut to obtain a glass sample having a thickness of 0.5 mm. The molten glass discharged from the melting furnace is supplied to the forming apparatus while being in contact with only platinum or a platinum alloy.
The obtained glass sample was observed with a 50-fold solid microscope, and when metal pits of 1 μm or more were observed in the observation field, the number of metal pits was counted as metal pits, and the number of metal pits per 1 ton (ton) of glass was calculated from the glass size used for measurement. The results are shown in Table 1.
As is clear from Table 1, since the β -OH numbers of sample Nos. 1 to 6 were as large as 0.12/mm or more, the number of metal pits was as small as 13.8/ton or less. Fig. 2 shows a graph in which β -OH values are plotted on the horizontal axis and metal pits are plotted on the vertical axis. As can be seen from FIG. 2, the larger the β -OH value, the smaller the number of metal pits.
The β -OH value of the glass was determined by FT-IR to determine the transmittance of the glass, and the value was obtained by the following formula.
beta-OH value= (1/X) log10 (T 1 /T 2 )
X: glass wall thickness (mm)
T 1 : reference wavelength 3846cm -1 Transmittance at time (%)
T 2 : hydroxyl absorption wavelength 3600cm -1 Minimum transmittance in the vicinity (%)
Claims (10)
1. A method for producing an alkali-free glass substrate, characterized by comprising the steps of,
the manufacturing method is to continuously manufacture SiO 2 -Al 2 O 3 A method for producing an alkali-free glass substrate of RO system, wherein RO is one or more of MgO, caO, baO, srO and ZnO,
the manufacturing method comprises the following steps:
a step of preparing a raw material batch so as to contain a tin compound and substantially contain no arsenic compound and no antimony compound;
a step of electrically melting the prepared raw material batch in a melting furnace capable of being electrically heated by means of electrodes; and
a step of forming the molten glass into a plate shape by a down-draw method,
the beta-OH value of the obtained glass is more than 0.05/mm, and the number of metal pits is less than 20/ton.
2. The method for producing an alkali-free glass substrate according to claim 1, wherein,
the beta-OH value and the number of metal pits of the obtained glass are regulated by utilizing glass raw materials and/or melting conditions.
3. The method for producing an alkali-free glass substrate according to claim 1 or 2, wherein,
without being heated by radiation from the burner combustion.
4. The method for producing an alkali-free glass substrate according to any one of claim 1 to 3, wherein,
the manufacturing method comprises the steps of 2 O 3 As a method for producing an alkali-free glass substrate having a glass composition,
orthoboric acid is used as at least a part of the glass raw material serving as a boron source.
5. The method for producing an alkali-free glass substrate according to any one of claim 1 to 4, wherein,
the hydroxide feedstock is contained in a feedstock batch.
6. The method for producing an alkali-free glass substrate according to any one of claim 1 to 5, wherein,
the manufacturing method is a method for manufacturing an alkali-free glass substrate by adding glass cullet to a raw material batch,
glass cullet containing glass having a beta-OH value of 0.05/mm or more is used as at least a part of the glass cullet.
7. The method for producing an alkali-free glass substrate according to claim 6, wherein,
the metal is removed by passing the glass cullet through the magnetic separator twice or more.
8. The method for producing an alkali-free glass substrate according to any one of claim 1 to 7, wherein,
the strain point of the obtained glass is 690 ℃ or higher.
9. The method for producing an alkali-free glass substrate according to any one of claim 1 to 8, wherein,
the heat shrinkage of the obtained glass was 25ppm or less.
10. The method for producing an alkali-free glass substrate according to any one of claim 1 to 9, wherein,
the manufacturing method is used for manufacturing a glass substrate for forming an oxide TFT.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2020-209435 | 2020-12-17 | ||
| JP2020209435A JP2022096375A (en) | 2020-12-17 | 2020-12-17 | Method for producing alkali-free glass substrate |
| PCT/JP2021/041181 WO2022130831A1 (en) | 2020-12-17 | 2021-11-09 | Method for producing alkali-free glass substrate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116648438A true CN116648438A (en) | 2023-08-25 |
Family
ID=82057526
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202180084882.2A Pending CN116648438A (en) | 2020-12-17 | 2021-11-09 | Method for manufacturing alkali-free glass substrate |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JP2022096375A (en) |
| KR (1) | KR20230122005A (en) |
| CN (1) | CN116648438A (en) |
| WO (1) | WO2022130831A1 (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101449491B1 (en) | 2013-01-02 | 2014-10-08 | 경창산업주식회사 | Forming Method for Toothed Component |
| WO2018123505A1 (en) * | 2016-12-26 | 2018-07-05 | 日本電気硝子株式会社 | Alkali-free glass substrate production method |
| CN111051255A (en) * | 2017-09-05 | 2020-04-21 | 日本电气硝子株式会社 | Method for producing alkali-free glass substrate and alkali-free glass substrate |
| JP7220583B2 (en) * | 2019-02-14 | 2023-02-10 | ＡｖａｎＳｔｒａｔｅ株式会社 | Glass substrate manufacturing method |
| CN117164229A (en) * | 2019-04-12 | 2023-12-05 | Ａｇｃ株式会社 | Glass sheet and method for manufacturing same |
-
2020
- 2020-12-17 JP JP2020209435A patent/JP2022096375A/en active Pending
-
2021
- 2021-11-09 CN CN202180084882.2A patent/CN116648438A/en active Pending
- 2021-11-09 WO PCT/JP2021/041181 patent/WO2022130831A1/en active Application Filing
- 2021-11-09 KR KR1020237019314A patent/KR20230122005A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| WO2022130831A1 (en) | 2022-06-23 |
| KR20230122005A (en) | 2023-08-22 |
| JP2022096375A (en) | 2022-06-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111268913B (en) | Microcrystalline glass product for electronic device cover plate and microcrystalline glass | |
| KR102532702B1 (en) | Alkali-free glass substrate manufacturing method and alkali-free glass substrate | |
| KR101790478B1 (en) | High Strain Point Aluminosilicate Glasses | |
| KR101528396B1 (en) | Glass substrate for flat pannel display | |
| CN109133615B (en) | Glass substrate for display and method for manufacturing same | |
| KR20220140021A (en) | Dimensionally stable fast etching glasses | |
| JP2015512849A5 (en) | ||
| JP2018104265A (en) | Manufacturing method of non-alkali glass substrate | |
| KR101178027B1 (en) | Production method of glass substrate for liquid crystal display | |
| WO2018123505A1 (en) | Alkali-free glass substrate production method | |
| JP2024059962A (en) | Dimensionally Stable Glass | |
| US20200325060A1 (en) | Method for producing glass plate | |
| TWI680113B (en) | Glass substrate for display and manufacturing method thereof | |
| JP7421161B2 (en) | Method for manufacturing alkali-free glass substrate and alkali-free glass substrate | |
| WO2021261446A1 (en) | Method for manufacturing low alkali glass plate, and low alkali glass plate | |
| CN116648438A (en) | Method for manufacturing alkali-free glass substrate | |
| CN116075487A (en) | Method for producing low alkali glass plate and low alkali glass plate | |
| KR20160125350A (en) | Silicate glass production method, silicate glass, and silica raw material for silica glass |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |