WO2001028943A1 - Transparent glass-ceramics based on alpha- and beta-willemite - Google Patents
Transparent glass-ceramics based on alpha- and beta-willemite Download PDFInfo
- Publication number
- WO2001028943A1 WO2001028943A1 PCT/US2000/028233 US0028233W WO0128943A1 WO 2001028943 A1 WO2001028943 A1 WO 2001028943A1 US 0028233 W US0028233 W US 0028233W WO 0128943 A1 WO0128943 A1 WO 0128943A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- glass
- ceramic
- willemite
- crystal phase
- ceramics
- Prior art date
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Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/0229—Optical fibres with cladding with or without a coating characterised by nanostructures, i.e. structures of size less than 100 nm, e.g. quantum dots
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B32/00—Thermal after-treatment of glass products not provided for in groups C03B19/00, C03B25/00 - C03B31/00 or C03B37/00, e.g. crystallisation, eliminating gas inclusions or other impurities; Hot-pressing vitrified, non-porous, shaped glass products
- C03B32/02—Thermal crystallisation, e.g. for crystallising glass bodies into glass-ceramic articles
-
- 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
- C03C10/00—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition
- C03C10/0036—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition containing SiO2, Al2O3 and a divalent metal oxide as main constituents
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/64—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing aluminium
- C09K11/646—Silicates
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/67—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing refractory metals
- C09K11/68—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing refractory metals containing chromium, molybdenum or tungsten
- C09K11/685—Aluminates; Silicates
Definitions
- TRANSPARENT LITHIUM, ZINC, MAGNESIUM
- TRANSPARENT LITHIUM, ZINC, MAGNESIUM
- GLASS-CERAMICS An application entitled TRANSPARENT (LITHIUM, ZINC, MAGNESIUM) ORTHOSILICATE GLASS-CERAMICS, filed as a United States Provisional Application Serial Number 60/159,967, on October 18, 1999, in the names of George H. Beall and Linda R. Pinckney, and assigned to the same assignee as this application, is directed to transition-metal-doped, glass-ceramic materials that exhibit properties that make them suitable as gain media in optical amplifiers and/or laser pumps.
- the present invention relates to transparent glass ceramics, and in particular to substantially transparent glass-ceramics based on crystals of alpha- and beta-willemite.
- Glass-ceramics are polycrystalline materials formed by a controlled crystallization of a precursor glass.
- the method for producing such glass- ceramics customarily involves three fundamental steps: first, a glass-forming batch is melted; second, the melt is simultaneously cooled to a temperature at least below the transformation range thereof and a glass body of a desired geometry shaped therefrom; and third, the glass body is heated to a temperature above the transformation range of the glass in a controlled manner to generate crystals in situ. Frequently, the glass body is exposed to a two-stage treatment. Hence, the glass will be heated initially to a temperature within, or somewhat above, the transformation range for a period of time sufficient to cause the development of nuclei in the glass.
- the temperature will be raised to levels approaching, or even exceeding, the softening point of the glass to cause the growth of crystals on the previously-formed nuclei.
- the resultant crystals are commonly more uniformly fine-grained, and the articles are typically more highly crystalline.
- Internal nucleation allows glass-ceramics to possess such favorable qualities as a very narrow particle size distribution and highly uniform dispersion throughout the glass host.
- Transparent glass-ceramics are well known to the art; the classic study thereof being authored by G. H. Beall and D.A. Duke in "Transparent Glass- Ceramics", Journal of Materials Science, 4, pp. 340-352 (1969). Glass-ceramic bodies will display transparency to the human eye when the crystals present therein are considerably smaller than the wavelength of visible light. More specifically, transparency generally results from crystals less than 50 nm, and preferably as low as 10 nm in size. Recently, much effort has been concentrated in the area of using transparent glass-ceramics as hosts for transition metals which act as optically active dopants. Suitable glass-ceramic hosts must be tailored such that transition elements will preferentially partition into the crystals. Co-pending application Serial No.
- 60/160,053 entitled “Transition Metal Glass-Ceramics” by Beall et al. is co-assigned to the present assignee, and is herein incorporated by reference in its entirety It is directed to transition-metal doped glass-ceramics suitable for formation of a telecommunications gain or pump laser fiber.
- Transparent glass-ceramics which contain relatively small numbers of crystals can be of great use in cases where the parent glass provides an easy- to-melt or an-easy-to-form vehicle for a crystal.
- the crystal in itself, may be difficult or expensive to synthesize, but may provide highly desirable features, such as optical activity.
- the crystals in the glass-ceramic are generally oriented randomly throughout the bulk of the glass, unlike a single crystal which has a specific orientation. Random orientation, and consequent anisotropy, are advantageous for many applications, one example being that of optical amplifiers, where polarization-independent gain is imperative.
- Transparent glass-ceramics doped with transition elements can combine the optical efficiency of crystals with the forming flexibility of glass.
- both bulk (planar) and fiber forms can be fabricated from these glass- ceramics. Therefore, there exists a need for transparent glass-ceramic materials which contain small tetrahedral and interstitial sites, and hence are suitable as potentially valuable hosts for small, optically active transition elements.
- Such elements include, but are not limited to, Cr 4+ , Cr 3+ , Co 3+ , Co 2+ , Cu 2+ , Mn 2+ , Cu 2+ , and Ni 2+ . These elements impart luminescence and fluorescence to such doped, glass-ceramic materials, thereby rendering them suitable for application in the optical field industry.
- the crystal structures of both alpha- and beta-willemite consist of frameworks of SiO 4 and Zn0 4 tetrahedra.
- the alpha-willemite structure was determined in 1930. It is isostructural with phenacite (Be 2 SiO ), with rhombohedral space group R 3, and consists of linked SiO 4 and ZnO 4 tetrahedra. All Zn 2+ ions occur in tetrahedral coordination. Each oxygen atom is linked to one silicon and two zinc atoms.
- the beta-willemite phase has a crystal structure related to those of the silica polymorphs tridymite and cristobalite. Half of the zinc ions are in tetrahedral coordination while the remaining half lie in interstitial positions.
- beta-willemite phase offers several potentially useful properties. Unlike alpha-willemite, beta-willemite can have a widely variable composition, ranging from 33 to 67 mole % ZnO. This wide range of solid solution allows the phase to be obtained in glass-ceramics of widely varying composition. Glass-ceramics containing the alpha-willemite form of Zn 2 SiO are known, particularly as materials for electronic applications. United States Patent No. 4,714,687 is directed to glass-ceramic materials containing wiUemite as a predominant crystal phase and especially designed for substrates in integrated circuit packaging.
- the glass-ceramic consists essentially, in terms of weight percent, of 30-55 Si0 2 , 10-30 AI 2 O 3 , 15-45 ZnO, and 3-15 MgO.
- a willemite glass-ceramic material that is transparent and is suitable for employment in the fiber optic industry.
- the primary object of the present invention is to provide glass-ceramic materials which are substantially and desirably totally transparent, and which contain a predominant willemite crystal phase.
- Another object of the present invention is to provide such willemite glass-ceramics which are capable of being doped with ingredients that confer luminescence and/or fluorescence thereto.
- An important advantage of the present glass-ceramic family is that it provides a material containing a willemite crystalline phase which can be tetrahedrally-coordinated with transition metal ions including, but not limited to,
- the material is glass-based thus providing the important flexibility of allowing for fabrication of both bulk (such as planar substrates) and fiber (such as optical fiber) forms.
- bulk such as planar substrates
- fiber such as optical fiber
- a transparent glass-ceramic containing a predominant crystal phase of alpha- and/or beta- willemite and having a composition consisting essentially, in weight percent on an oxide basis, of 25-60 SiO 2 , 4-20 AI 2 O 3 , 20-55 ZnO, 0-12 MgO, 0-18 K 2 O, 0- 12 Na 2 O, 0-30 GeO 2 , with the condition that ⁇ K 2 0+ Na 2 O > 5.
- the most preferred composition will consist essentially, expressed in terms of weight percent on the oxide basis, of 35-50 Si0 2 , 8-15 AI 2 O 3 , 30-42 ZnO, 0-5 MgO, 3-10 K 2 O, 0-6 Na 2 O, 0-5 GeO 2 .
- optical activity in the present inventive willemite glass-ceramic materials, i.e., fluorescence, over the communications transmission wavelength range of 1100 to 1700 nm, up to 1 wt. % Cr 2 O 3 may be added to the parent glass.
- a method of making comprising the steps of: a.) melting a batch for a glass having a composition consisting essentially, in weight percent on an oxide basis, of 25-60 SiO 2 , 4-20 Al 2 0 3 , 20- 55 ZnO, 0-12 MgO, 0-18 K 2 O, 0-12 Na 2 O, 0-30 GeO 2 , with the condition that ⁇ K 2 O+ Na 2 O > 5; b.) cooling the glass to a temperature at least below the transformation range of the glass; c.) exposing the glass to a temperature between about 550-950°C for a period of time sufficient to cause the generation of a glass-ceramic which is substantially transparent and which contains a predominant willemite crystal phase; and, d.) cooling the glass-ceramic to room temperature.
- FIG. 1 is a powder X-ray diffraction spectra of a glass-ceramic that has the composition of Example 2, that has been produced by heat treating at 975°C for 2 hours and that shows a predominant crystal phase of ⁇ -willemite.
- FIG. 2 is a powder X-ray diffraction spectra of a glass-ceramic that has the composition of Example 2, that has been produced by heat treating at 850°C for 2 hours and that shows a predominant crystal phase of ⁇ -willemite.
- FIG. 3 shows the fluorescence spectra for the glass-ceramics of Examples 2 and 13 when doped with 0.08 wt. % Cr 2 O 3 .
- the present inventive, substantially transparent, willemite glass- ceramics have compositions consisting essentially, in weight percent on an oxide basis, of
- the most preferred composition range consists essentially, in weight percent on an oxide basis, of
- the following Table sets forth a number of glass compositions, expressed in terms of parts by weight on the oxide basis, illustrating the parameters of the present invention.
- the Table also presents the ceramming schedule in °C and hours, as well as the crystal phases observed in the final glass-ceramics.
- the batch ingredients for preparing glasses falling within the inventive composition ranges may comprise any materials, either the oxides or other compounds, which, upon being melted together, will be converted into the desired oxide in the proper proportions.
- the exemplary glasses were produced in the following manner.
- the batch materials were compounded, mixed together to assist in securing a homogeneous melt, and then placed into platinum crucibles.
- the crucibles were introduced into a furnace operating at temperatures of 1400-1600°C, and the batches were melted for 4-16 hours.
- the melts were poured as free
- the glass patties were subjected to the ceramming cycle by placing them into a furnace and heat treating according to the following schedule: 300°C/hour to a crystallization temperature T°C, hold at T°C for 1-2 hours, and cool at furnace rate.
- the crystallization temperature T varied from 650-900°C, such that a substantially transparent, willemite glass-ceramic was obtained.
- inventive compositions are self-nucleating due to liquid-liquid phase separation and therefore require no added nucleating agents. More specifically, nucleation is promoted by amorphous phase separation. Even though nucleating agents are not required, in many cases the addition of nucleating agents, such as TiO 2 (4 wt. %), results in a finer crystal size and improved transparency: Care must be taken to avoid spontaneous crystallization in the annealer, however.
- the addition of germania tends to stabilize the alpha-willemite polymorph over the beta-willemite polymorph.
- the crystalline phases of the resulting glass-ceramic materials were identified using X-ray powder diffraction. Representative diffraction patterns are shown in FIG. 1 for a glass having the composition of Example 2 that has been heat treated at 975°C for 2 hours, and in FIG. 2 for a glass having the composition of Example 2 that has been heat treated at 850°C for 2 hours.
- the structure of the inventive glass-ceramics contains microcrystals (10- 50 nm in size) of alpha- and/or beta-willemite in a stable alkali aluminosilicate glass, with total crystallinity ranging from about 10% to 50% by volume depending on the individual composition.
- the microcrystals are internally grown in the base glass during the ceramming cycle. Transparency in the inventive glass ceramics is a function of microstructure which in turn is a function of the composition.
- the crystal structure in the present inventive glass-ceramic material provides only small tetrahedral and interstitial sites. This feature renders the crystals potentially valuable hosts for small, optically active transition elements including, but not limited to, Cr 4+ , Cr 3+ , Co 3+ , Co 2+ , Cu 2+ , Mn 2+ , Cu 2+ , and Ni 2+ . These transition elements will fluoresce and luminesce at various wavelengths. While larger amounts of some of these elements may be incorporated in the precursor glasses, the amount employed in the present glasses will normally not exceed about 1% by weight.
- crystals with tetrahed rally- coordinated Cr 4+ ions provide unique optical characteristics. Therefore, in one possible application, the present inventive, transparent, willemite glass- ceramics, doped with transition metal ions, are suitable for employment in the optics and laser industries. Specific applications include, but are not limited to, optical amplifiers and pump lasers.
- Examples 2 and 3 were doped with 0.08 wt. % chromium oxide and fluorescence measurements were taken. As shown in FIG. 2, strong Cr 4+ emission was observed, over the communications transmission wavelength range between 1100-1700 nm, in both glass- ceramics.
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- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Physics & Mathematics (AREA)
- Inorganic Chemistry (AREA)
- Ceramic Engineering (AREA)
- Thermal Sciences (AREA)
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- Chemical Kinetics & Catalysis (AREA)
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Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU80161/00A AU8016100A (en) | 1999-10-18 | 2000-10-12 | Transparent glass-ceramics based on alpha- and beta-willemite |
JP2001531736A JP2003512281A (en) | 1999-10-18 | 2000-10-12 | α- and β-willemite based transparent glass ceramic |
EP00970840A EP1254080A1 (en) | 1999-10-18 | 2000-10-12 | Transparent glass-ceramics based on alpha- and beta-willemite |
CA002387951A CA2387951A1 (en) | 1999-10-18 | 2000-10-12 | Transparent glass-ceramics based on alpha- and beta-willemite |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US16013899P | 1999-10-18 | 1999-10-18 | |
US60/160,138 | 1999-10-18 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2001028943A1 true WO2001028943A1 (en) | 2001-04-26 |
Family
ID=22575686
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2000/028233 WO2001028943A1 (en) | 1999-10-18 | 2000-10-12 | Transparent glass-ceramics based on alpha- and beta-willemite |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP1254080A1 (en) |
JP (1) | JP2003512281A (en) |
CN (1) | CN1184157C (en) |
AU (1) | AU8016100A (en) |
CA (1) | CA2387951A1 (en) |
TW (1) | TW503225B (en) |
WO (1) | WO2001028943A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004060825A1 (en) * | 2002-12-31 | 2004-07-22 | Corning Incorporated | GLASS CERAMICS BASED ON ZnO |
EP1457544A1 (en) * | 2001-12-21 | 2004-09-15 | GE Betz, Inc. | Phosphor and method for production thereof and plasma display device |
EP1405834A3 (en) * | 2002-10-02 | 2006-01-04 | Schott Ag | Multicomponent glass optical fibres |
US8871664B2 (en) | 2010-05-10 | 2014-10-28 | Nippon Electric Glass Co., Ltd. | Refractory filler, sealing material using same, and manufacturing method for refractory filler |
US9593039B2 (en) | 2013-02-28 | 2017-03-14 | Centre National De La Recherche Scientifique (Cnrs) | Nanostructured glasses and vitroceramics that are transparent in visible and infra-red ranges |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5605748B2 (en) * | 2010-04-22 | 2014-10-15 | 日本電気硝子株式会社 | Refractory filler powder, sealing material and method for producing refractory filler powder |
JP5773128B2 (en) * | 2010-05-10 | 2015-09-02 | 日本電気硝子株式会社 | Method for producing refractory filler |
CN103194229A (en) * | 2013-03-29 | 2013-07-10 | 华南理工大学 | Near-infrared long-afterglow florescent powder and preparation method thereof |
CN103466949B (en) * | 2013-08-21 | 2015-10-28 | 中国计量学院 | A kind of precipitation Zn 1.7siO 4nanocrystalline devitrified glass and preparation method thereof |
CN103539358B (en) * | 2013-09-26 | 2016-03-02 | 中国计量学院 | The method of the controlled precipitation of a kind of super-broadband fiber amplifier transparent glass-ceramics crystalline phase |
CN103833228B (en) * | 2014-01-23 | 2015-10-28 | 中国计量学院 | Chromium ion-doped devitrified glass of a kind of tetravalence and preparation method thereof |
CN114634353B (en) * | 2020-12-16 | 2023-04-18 | 山东国瓷功能材料股份有限公司 | Low-dielectric low-loss near-zero temperature drift low-temperature co-fired ceramic material and preparation method thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4714687A (en) * | 1986-10-27 | 1987-12-22 | Corning Glass Works | Glass-ceramics suitable for dielectric substrates |
US6120906A (en) * | 1997-03-31 | 2000-09-19 | Kyocera Corporation | Insulated board for a wiring board |
-
2000
- 2000-10-12 AU AU80161/00A patent/AU8016100A/en not_active Abandoned
- 2000-10-12 CN CNB008143374A patent/CN1184157C/en not_active Expired - Fee Related
- 2000-10-12 WO PCT/US2000/028233 patent/WO2001028943A1/en active Application Filing
- 2000-10-12 EP EP00970840A patent/EP1254080A1/en active Pending
- 2000-10-12 JP JP2001531736A patent/JP2003512281A/en active Pending
- 2000-10-12 CA CA002387951A patent/CA2387951A1/en not_active Abandoned
- 2000-10-17 TW TW89122007A patent/TW503225B/en not_active IP Right Cessation
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4714687A (en) * | 1986-10-27 | 1987-12-22 | Corning Glass Works | Glass-ceramics suitable for dielectric substrates |
US6120906A (en) * | 1997-03-31 | 2000-09-19 | Kyocera Corporation | Insulated board for a wiring board |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1457544A1 (en) * | 2001-12-21 | 2004-09-15 | GE Betz, Inc. | Phosphor and method for production thereof and plasma display device |
EP1457544A4 (en) * | 2001-12-21 | 2008-04-02 | Matsushita Electric Ind Co Ltd | Phosphor and method for production thereof and plasma display device |
EP1405834A3 (en) * | 2002-10-02 | 2006-01-04 | Schott Ag | Multicomponent glass optical fibres |
WO2004060825A1 (en) * | 2002-12-31 | 2004-07-22 | Corning Incorporated | GLASS CERAMICS BASED ON ZnO |
US6936555B2 (en) | 2002-12-31 | 2005-08-30 | Corning Incorporated | Glass ceramics based on ZnO |
US8871664B2 (en) | 2010-05-10 | 2014-10-28 | Nippon Electric Glass Co., Ltd. | Refractory filler, sealing material using same, and manufacturing method for refractory filler |
US9593039B2 (en) | 2013-02-28 | 2017-03-14 | Centre National De La Recherche Scientifique (Cnrs) | Nanostructured glasses and vitroceramics that are transparent in visible and infra-red ranges |
Also Published As
Publication number | Publication date |
---|---|
AU8016100A (en) | 2001-04-30 |
CN1379742A (en) | 2002-11-13 |
CA2387951A1 (en) | 2001-04-26 |
EP1254080A1 (en) | 2002-11-06 |
JP2003512281A (en) | 2003-04-02 |
TW503225B (en) | 2002-09-21 |
CN1184157C (en) | 2005-01-12 |
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