CA1062969A - Coating glass - Google Patents
Coating glassInfo
- Publication number
- CA1062969A CA1062969A CA 240560 CA240560A CA1062969A CA 1062969 A CA1062969 A CA 1062969A CA 240560 CA240560 CA 240560 CA 240560 A CA240560 A CA 240560A CA 1062969 A CA1062969 A CA 1062969A
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- CA
- Canada
- Prior art keywords
- metal
- glass
- alloy
- group
- substrate
- 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.)
- Expired
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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
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/22—Surface treatment of glass, not in the form of fibres or filaments, by coating with other inorganic material
- C03C17/23—Oxides
- C03C17/245—Oxides by deposition from the vapour phase
-
- 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
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/22—Surface treatment of glass, not in the form of fibres or filaments, by coating with other inorganic material
- C03C17/23—Oxides
-
- 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
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/22—Surface treatment of glass, not in the form of fibres or filaments, by coating with other inorganic material
- C03C17/23—Oxides
- C03C17/25—Oxides by deposition from the liquid phase
-
- 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
- C03C21/00—Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface
-
- 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
- C03C2217/00—Coatings on glass
- C03C2217/20—Materials for coating a single layer on glass
- C03C2217/21—Oxides
-
- 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
- C03C2217/00—Coatings on glass
- C03C2217/20—Materials for coating a single layer on glass
- C03C2217/21—Oxides
- C03C2217/229—Non-specific enumeration
-
- 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
- C03C2218/00—Methods for coating glass
- C03C2218/10—Deposition methods
- C03C2218/11—Deposition methods from solutions or suspensions
-
- 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
- C03C2218/00—Methods for coating glass
- C03C2218/10—Deposition methods
- C03C2218/15—Deposition methods from the vapour phase
- C03C2218/152—Deposition methods from the vapour phase by cvd
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)
- Surface Treatment Of Glass (AREA)
- Chemically Coating (AREA)
Abstract
COATING GLASS
Harold E. Donley Abstract of the Disclosure Glass having a color-imparting pure metal or metal alloy concentrated in the glass matrix near its surface is coated with a metal oxide film to produce durable articles in a variety of colors suitable for architectural use to control incident solar energy.
Harold E. Donley Abstract of the Disclosure Glass having a color-imparting pure metal or metal alloy concentrated in the glass matrix near its surface is coated with a metal oxide film to produce durable articles in a variety of colors suitable for architectural use to control incident solar energy.
Description
_a_ ground of the Inve t:ion 1. Field of the Invention '' ' ' This invention relates to coated glass and particuîarly,relates . ., to the production of metal oxide coated glass articles.
2. Description of the Prior ~rt - , '` ' , .
In the preparation of metal or metal oxide films on large sub-strates there has'been a significant body of teaching relating to the preparation of such coatings by pyrolytic techniques. The art of pyrolytic coating of glass is characterized by the following patents:
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U. S. Patent No. 3,081,200 to Tompkins and U.S. Patent No.
In the preparation of metal or metal oxide films on large sub-strates there has'been a significant body of teaching relating to the preparation of such coatings by pyrolytic techniques. The art of pyrolytic coating of glass is characterized by the following patents:
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U. S. Patent No. 3,081,200 to Tompkins and U.S. Patent No.
3,410,710 to Mochel teach that metal oxide coatings~may be applied to , , ;.
,~; refractory materials by contacting the refractory, ~/hile hot, ~ith compo-"
~ sitions containing metal diketonates.
;-~ U. S. Patent No. 3,652,246 to Michelotti and lienry an(l U. S.
i Patent No. 3,660,061 to Donley, Rieser and Wa~ner teach the application ;. .
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of metal oxide coating on a continuous ribbon of float glass having dis-solved tin in its surface régions.
These described patents provide a recent history of the develop-; ment of the art of coating glass with metal oxides by pyrolysis. As each improvement in turn has been implemented, coatings of improved quality both as to appearance and durability have been obtained. Metal oxides of a variety of metals may be deposited on glass by techniques known in the art. Metal oxides deposited in the manner taught by Donley, Rieser and Wagner are found to adhere to glass with sufficient tenacity to provide coatings capable of withstanding prolonged atmospheric attack in exposed -architectural applications. However, accelerated weathering tests have shown that, depending upon the partlcular metal oxide or combinations of metsl oxides present in the coating compositions, some of the metal oxide coatings will fail after prolonged exposure to corrosive atmospheres, such as those containing acldic pollutants or salt water. Improved durability of all useful metal oxide coatings on glass has been considered a desirable objective. Also, since the composition changes necessary to produce differ-ing color effects yield films of differing durability, it has been an objectlve to increase the range of colors that may be achieved with a given composition so that a variety of colors are available for use without the ~ !
necessity of prolonged durability testing for each new colored coating prior to its use. I
In U. S. Patent No. 3,467,508 Loukes st al teach a method of making colored glass articles. By modifying the surface of the glass substrate with selected metals, other than the tin which is normally present at the surface of float formed soda-lime-silica glass, it is possible to provide the glass with stained surface layers of various desired colors. Unfortu-nately, such ~etal modified glass surfaces, characterized in the art as ~L~6Z~69 "ion-exchanged" surfaces, are relatively soft and are easily damaged by mild abrasion. Therefore, it is practical to limit ; the use of such articles to interior appiications or use in double glazed windows where durability is not as critical as for exposed exterior surfaces.
Coatings made by the described pyrolytic techniques ! and stains made by the described "ion-exchange" technique yield colored articles wherein the colors depend on the composition of the coloring medium. In order to obtain different colors it is necessary to modify the components of the coloring medium.
i A preferable result would follow from the ability to utilize ~-the same basic composition to provide a variety of colors.
It is known that selectively reflecting and transmitting interference filters can be produced by using materials of widely different indices of refraction in multiple-layer films `~
of controlled thicknesses. Such multiple-layer films have been -designed to effectively filter out all but narrow bands of light having the desired dominant wavelengths. These prior art i multiple-layer films have usually been made by vaccum evaporation ;1 20 deposition techniques. Such evaporation deposition methods are not readily adaptable to continuously coating large sheets of glass for use as viewing enclosures in architectural applications.
On the other hand, pyrolytic techniques normally used to f.':~ .
continuously coat large sheets of glass are not particularly `~ suited to making multiple-layer films. Reheating would generally `~
be required between coating steps and this can easily cause -s distortion in both the glass and the previously applied layers of the final film. ~`
SUMMARY OP THE INVENTION
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In accordance with one aspect of the invention there is ' provided an article of manufacture for the selective transmittance of solar radiation over an extended spectral ~6zg6~
range comprising a glass substrate having a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth concentrated in a surface region of the glass substrate which concentration is greater at the surface than at the interior of the substrate and having a metal oxide overcoat of a metal selected from the group consisting of cobalt, iron, chromium, copper, manganese, nickel, vanadium, titanium and mixtures thereof applied to the surface. Y
In a further aspect of the invention there is provided a method of coating a glass subs~rate comprising the steps of: a) contacting a surface of the substrate with a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth at a sufficiently high temperature to provide for migration of the metal into the contacted surface and b) contacting the modified surface of the substrate with a coating composition containing a metal compound at a } ;~
sufficiently high temperature to convert the metal compound to a metal oxide by thermal reaction on contact with the glass substrate.
It will therefore be seen that the surface of a glass substrate is modified by dissolving at least one metal, other than or in addition to tin, into a surface of the glass `substrate. This modification is preferably accomplished by con~acting :
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~i2969 the glass surface with a pure metal or metal alloy under reducing conditions and at a temperature sufficient to permlt migration of the metal into the glass surface where it may be present in metallic form or incorporated into the oxide matrix of the glass. The modified surface, preferably while still at an elevated temperature and preferably after brief exposure to an oxidiz- -ing atmosphere, is contacted with a metal-containing coating composition under such conditions as to cause pyrolyzation of the coating composition and deposition of a metal oxide coating on the surface of the substrate.
The resultant articles exhibit increased solar energy control capabilities, improved durability, and flexibility in the selection of reflected and transmitted colors when compared with articles made by the techniques of the previously described references.
The present invention provides a method for producing metal oxide -- .
coated glass of surprisingly superior durability and, in addition, is capable , of providing a wide range of uniform colors heretofore unattainable by pyrolytic techniques.
Applying the method of the present invention allows one to produce certain uniform colors, previously obtainable only by interference techniques employing multiple-layer films, by using pyrolytic techniques. A single j coating may be employed to obtain a variety of color effects heretofore :
obtainable only with multiple-layer coatings, thereby eliminating significant ~ reheating costs. This single coating can be applied at the glass surface in ,, .
a continuous run procedure using pyrolysis for application of a metal oxide i film after dissolving a color imparting metal into the immediate surface of the glass substrate. In order to obtain articles having particular reflec-tance and transmittance characteristics and exhibiting desired color character-~-~ istics when viewed either in reflectance or transmittance, metals or combina-`i tions thereof having a particular index of refraction are selected and the ` , . ' .
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31L~62~69 thicknesses of the modified glass-metal layer and of the metal oxide film are controlled.
- ~ pure metal or metal alloy is dissolved into the surface of the glass matrix by maintaining molten, solid, or vaporized metal in contact with the glass surface at an elevated temperature, preferably -above the softening point of the glass and under reducing conditions. The dissolution of pure metal or metal alloy may be permitted to proceed by diffusion with thermal energy alone to enhance the rate of metal dissolution or the rate may be accelerated by electrochemical techniques such as by providing an electric potential across the contacting metal and the glass. -When an electric potential is used as the driving force, the metal or alloy is maintained on the surface of a glass substrate, which is to be modified, and another surface of the substrate is contacted with an electro-conductive material in an area opposite the metal or alloy.
The metal confined on the surface of the glass may be an alloy of tin, lead or bismuth. For example, the metal may be an alloy of tin with an .~ .
i element selected from the group of elements consisting of lithium, sodium, potassium, zinc, magnesium, vanadium, cobalt, nickel, copper, aluminum, ~ silicon, titanium, manganese, chromium and iron. The alloy may be an alloy `` ~ of tin with one of the rare earth metaIs. When employing a tin alloy, the ; relative concentration of the tin and the other metal and their relative i- chemical properties determines whether only the metal alloyed with the tin ~; enters the surface of the glass.
`-1 In other applications of the invention, the metal employed may be an alloy of bismuth or lead with an element selected from the group consisting of lithium, sodium, zinc, magnesium, vanadium, aluminum, silicon, ,~ titanium, manganese, chromium, iron, cobalt, nickel, copper, silver, gold, antimony, arsenic, and indium. Further, the metal may be an alloy of bismuth ., or lead with an element selected from the group consisting of the platinum .. ~ . ; .
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~CI 62969 group metals and the rare earth metals. The metal or metal alloy migrates into the glass matrix establishing a metal content in the glass which is greatest near th~ contacted surface and decreases toward the interior of the glass.
In preferred applications of the invention, the desired metal is confined on the surface of the substrate as a molten pool.
The surface of the glass which has been contacted with the metal is then contacted, while still at an elevated temperature, with a coating composition which pyrolyzes or otherwise reacts to form a metal oxide coating. This ~urther contacting may occur after a brief or a long exposure of the metal-containing glass to oxidizing conditions or may occur without interim oxidation.
The coating composition comprises a metal coating reactant which will pyrolyze or otherwise react to form a metal oxide coating upon contact with the glass and a solvent andlor a carrier gas for the coating reactants employed. The coating composition may be dispensed toward the glass as a liquid or vapor. ~ -Typical of the coating reactants which may be employed are organo-metallic salts lcnown in the coating art. Compounds such as acetatés, hexoates, and the like may be employed.
` While many organometallic salts, such as the acetates and 2-ethyl hexoates, are suitable to pyrolyze on contact with hot glass to form metal oxide films on the hot glass surface, superior films result from applying acetylacetonates of various metals in various relative concentrations in an organic vehicle to produce the desired colored appearance.
Various metal salts have well known film-forming properties. U. S.
Patent No. 3,244,547 to L. E. Orr et al., U. S. Patent No. 3j658,568 to Donley and U. S. Patent No. 2,564,708 show compositlons capable of forming ~.. ~''.
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~6Z~69 .
colored metal oxide films. However, to simplify storage and mixture problems, and to produce films having superlor durability, it is convenient to use a family of compositions containing one or more of the acetylacetonates of cobalt, iron and chromium.
Other pleaslngly colored coating compositions are produced by -using another family of compositions containing salts of one or more metals of the class consisting of copper, manganese and nickel. Still other suitable coloring compositions contain salts of one or more of any of the six metals enumerated above, as well as vanadium and titanium salts that form metal oxides by pyrolysis on contact with a glass surface. Other coatings, such as coatings comprising chromium oxide alone or in combination with iron oxide may , be effectively employed in this invention. For example, coatings comprising about 25 percent iron oxide and 75 percent chromium oxide deposited over clear or tinted glass containing copper in its surface region provide particularly ' desirable articles. ~ -¦ If a solvent is employed, as in the preferred embodiments, the solvent~should be relatively stable, non-explosive, have a high boiling polnt and not break down into corrosive products. Solvents which may be used to advantage include aliphatic and cyclic hydrocarbons, halocarbons and halo-genated hydrocarbons. Solvents, such as benzene and toluene, may be employed for economy although certain performance advantages accrue from the use of halogen-contalning materials as pointed out below.
Methylene chloride (CH2C12) is an excellent solvent for many organometallic salts used, has a sufficiently high boiling point to remain a liquid until it contacts the hot glass ribbon, and is sufficiently non-explosive and non-flammable to be safe for handling. Furthermore, this solvent appears to be chemically stable and does not break down into corrosive ! compounds such as HCl and methane.
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~6Z969 `
Seyeral other aliphatic and olefinic halocarbons and halogenated hydrocarbons meet these requirements. These include:
methylene bromide (CH2Br2) carbon tetrachloride (CC14) carbon tetrabromide (CBr4) chloroform (CHC13) bromoform (CHBr3) l,l,l-trichloroethane (C13C-CH3) perchloroethylene (C12C=CC12) Cl Cl l l 1,1,2~trichloroethane (H-C,~CI-H) Cl ~l dichloroiodomethane (CHC12I) Br Br 1,1,2-tribromoethane (H-C-C~H) Br H
trichloroethylene (C12C=CClH) tribromoethylene (Br2C=CBr.H) Cl trichloromonofluoromethane (F-C-Cl) ~ -: Cl . hexachloroethane (CI3C-CC13) : :
ljl,l,2-tetrachloro-2-fluoroethane (C13C-CHClF) ; 1,1,2-trichloro~1,2~difluoroethane (FC12C~CHClF) tetrafluorobromoethane (F3C-CFBrH) or (F2BrC-CF2H) hexachlorobutadiene (CC12=CCI-CCl=CC12) and tetrachloroethane (C12HC-CHC123 - :: :
: ' In addition, mlxtures of two or more of the aforesaid organic solvents ,....
. which are compatible may be used.
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~Çi2969 Other solvents having superior dissolving power for the metal salts used, such as various mixtures of one or more organic polar compounds, such as an alcohol containing one to four carbon atoms and one hydroxyl group, or one or more aromatic non-polar compounds taken from the class consisting of benzene, toluene and xylene may be used with caution. However, their volatility makes them more difficult to handle than the solvents listed above.
This invention may be advantageously carried out in conjunction with a process for forming flat glass by floating it on molten tin. After the glass being formed has assumed a dimensionally stable configuration on a pool of molten tin, it is contacted on its top~surface with a pure metal or a metal alloy which migrates into the surface of the glass. The rate of migration may be accelerated by externally applied electrochemical forces. After leaving the float chamber, the surface of the glass which has been contacted by the metal is then contacted with a metal-containing coating composition while the glass temperature is maintained sufficiently high to cause pyrolysis of the coatlng composition. The glass may be subjected to an oxidi~ing atmosphere between the steps of metal migration and metal oxide~coating and this is preferred to further enhance the dura-bility of the resulting film. Apparatus for applying a metal oxide coating to the glass emerging from a float chamber is illustrated and described in U. S. Patents Nos. 3,660,061 and 3,689,304. If an annealed final product is desired, coating is accomplished by immediately spraying the glass ribbon with the metal oxide forming solution within seconds after it leaves the float forming chamber. The coated, annealed ribbon is then cut to the desired dimensions. If a tempered or heat strengthened product is desired, the heating and coating steps may be performed subsequent to the forming of glass or in a separate operation.
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; ~62~69 '~ .This method resul~s in an article which exhibits exceptional durability an~ also provides a wide variety of colors by reflectance and transmittance. The metal that is dispersed into the immediate surface layer of the glass substrate is relatively concentrated in the first micron or two beneath the surface. In general, this concentration gradually decreases until at a depth of about 12 to 14 microns there is only a trace of metal. The result is an alteration of the index of refraction at the ., .
glass surface while not affecting that of the remainder of the substrate.
The standard glass composition and the comparatively very thin comixture of glass and metal have distinctively different indices of refraction.
Coating such a modified surface of a glass substrate with a metal oxide ~, film produces ~wo unexpected results.
First is an unexpected increase in durability. The glass surface .~ .
as modified by the addition of metal is relatively soft and can be easily removed by mild abrasion. The described metal oxide films, when applied directly to an unmodified surface of a glass substrate, are durable and may be used in single gla~ed architectural applications. However, the combination of a durable metal oxide film and a soft, non-durable surface-modified substrate yields a product having significantly increased durability over one produced by applying the same metal oxide to a non-modified glass - ;
substrate, even one containing tin in its surface regions by virtue of its manufacture by floating on tin prior to coating.
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Second, the present invention allows the production of a variety of uniform colors with each coating composition employed. Such a variety of colors from a~ single composition had previously been unattainable by conventional pyrolytic techniques. In order to obtain a variety of colors by interference techniques, it is necessary to use two or more coatings, each of fixed composition having widely different indices of refraction in , -- 10 --, . ...
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~CI 62~169 alternate layers to provide multiple-layer films having optical thickness of approximately one-quarter of the wavelength of the visible light to be selectively reflected. The optical thickness of a film is defined as the actual thickness times the index of refraction. The median wavelength of the visible range is approximately 5,800 angstroms (580 nm). Therefore, in order to obtain interference colors having approximately this dominant wavelength, the optical thickness of the film should be approximately 1,450 angstroms (145 nm).
The bulk index of refraction of common glass is about 1.52. This value will vary slightly with composition, but remains essentially in the range of from 1.50 to 1.56 for such common glasses as soda-lime glasses.
The bulk index of refraction of the metal oxides used for the coatings in the present invention vary from about 2.0 to 3Ø The measured index of refraction of thin pyrolytic films is lower than the bulk index of refraction, but as the thickness of~a film is increased, void spaces in the film become filled and the index of refraction of the film approaches the bulk value for the metal oxide comprising the film. Metal oxide films at least 600-800 angstroms (60-80 nm) thick deposited on ordinary glass are observed to dis-play interference colors. However, it is difficult to produce pyrolytic films of this threshold thickness and maintain uniformity. Furthermore, .
the presence of interference colors accentuates the non-unlformity of the film.
By modifying the surface of the glass substrate to increase the index of refraction of the substrate, it is possible to produce-uniform colors, such as those produced by interference, using metal oxide films of less than one-quarter wavelength optical thickness. This result is unique in that such colors cannot be produced by applying thin films to normal tinted glasses or to the tin-enriched surface of float glass. Thls may be . ` .
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~a362~69 due to the fact that in neither process is there a significant increase in index of refraction over that of clear glass produced by conventional methods. The glass composition remains essentially unchanged with the tint being derived from the addition of a small concentration of colorant which is uniformly distributed throughout the entire thickness of the glass.
Concentrations of colorant as high as one percent are not uncommon in -commercially available tinted glasses. However, the concentratio`n is rela-tively constant throughout the glass, and metal oxide coatings on such glasses reflect a color that is essentially the same as that of the same coating on clear glass.
The invention will be more fully understood from the detailed descriptions of the preEerred embodiments which follow.
i! .. ' Description of the Preferred Embodiments .
Soda~lime-silica glass is prepared by compounding raw materials, melting them to form molten glass and refining the molten glass according to known techniques. Soda-lime-silica glasses normally contain by weight about 60 to 75 percent SiO2; 10 to 15 percent Na20; 0 to 5 percent K20, the sum of Na20 plus K20 being 10 to 15 percent; 5 to 15 percent CaO; O to 10 percent MgO, the sum of CaO and MgO being 5 to 15 percent; O to 1 percent A1203 and minor amounts of other ingredients for fining and coloring the glass. Examples of colored lime-soda-silica glasses are described in U. S.
, Patent Nos. Re. 25,31Z and 3,296,004.
; The process can be carried out by treating glass made by any - of the standard known flat glass processes such as float, sheet or plate ; glass. However, the float process is preferred.
; This invention may be further appreciated by reference to the following examples.
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j - 12 -~6Z~69 EXAMPLE I
Flat glass having the following approximate composition is produced - by floating the glass on molten tin in a reducing atmosphere containing tin vapors.
Percent by Weight SiO2 72.0 Na2O 13.3 K2O 0.6 CaO 8.9 MgO 3.8 12O3 1.0 3 0.3 Fe203 0 .10 ¦ The glass produced in accordance with this method has an equilib-j rium thickness of approximately one-quarter inch or seven millimeters.
Thls equilibrium thickness glass was used for all of the experiments described in the present examples.
! ~ During formation~ tin enters both the top surface and the bottom surface of the glass. The top surface of the glass is exposed during forming ~ to a gaseous atmosphere containing tin vapor in addition to nitrogen and -J~ hydrogen which fills the space in a forming chamber above the pool of molten tin on which the glass is floated to form it into flat glass. Ihe bottom surface of the glass rests directly on the pool of molten tin. The average temperature of the molten tin is from about 1400F. to about 1600F. The ~`~ glass is present in the tin-containing forming chamber for a period of from about 5 minutes to about 15 minutes.
In the forming chamber the top surface of the glass lS contacted ~ with a pool of molten copper and lead comprising about 2 percent by weight .,~
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1C36Z~;9 copper and about 98 percent by weight lead. An electric current is passed through the glass between the pool of the copper-lead alloy and the underlying pool of tin. Copper and lead are driven into the glass through its top surface. ' Presumably, some of the tin which has been dissolved into the surface during the float process and the alkali metals present at the surface in the glass matrix are driven from the glass. The lead ions, probably due to their size, re~
main essentially at the surface. The depth of copper ,~
penetration can be increased with an increase in voltage i~
across the system, but it too remains concentrated near the i' -surface. Variation of color by reflectance and transmittance can be attained by controlling the voltage in order to ~, produce a desired concentration and depth of penetration of the exchange metal or metal alloy. This is essentially the ' process described in U.S. Patent No. 3,467,508 to Loukes et al.
The resulting glass is removed and cooled without further treatment and analyzed by conventional electron probe techniques and exhibits copper and lead concentrations as shown here in percents by weight. Table I summarizes ;.'~
the properties of a colored glass substrate stained by the described surface modification method.
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6Z96~
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TABLE I
Depth Beneath Top Surface (Microns) Percent Cu Percent Pb 1.5 1.3 2.0 2.5 1.2 0.17 3.5 0.73 0.04
,~; refractory materials by contacting the refractory, ~/hile hot, ~ith compo-"
~ sitions containing metal diketonates.
;-~ U. S. Patent No. 3,652,246 to Michelotti and lienry an(l U. S.
i Patent No. 3,660,061 to Donley, Rieser and Wa~ner teach the application ;. .
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~f6~969 , . .
of metal oxide coating on a continuous ribbon of float glass having dis-solved tin in its surface régions.
These described patents provide a recent history of the develop-; ment of the art of coating glass with metal oxides by pyrolysis. As each improvement in turn has been implemented, coatings of improved quality both as to appearance and durability have been obtained. Metal oxides of a variety of metals may be deposited on glass by techniques known in the art. Metal oxides deposited in the manner taught by Donley, Rieser and Wagner are found to adhere to glass with sufficient tenacity to provide coatings capable of withstanding prolonged atmospheric attack in exposed -architectural applications. However, accelerated weathering tests have shown that, depending upon the partlcular metal oxide or combinations of metsl oxides present in the coating compositions, some of the metal oxide coatings will fail after prolonged exposure to corrosive atmospheres, such as those containing acldic pollutants or salt water. Improved durability of all useful metal oxide coatings on glass has been considered a desirable objective. Also, since the composition changes necessary to produce differ-ing color effects yield films of differing durability, it has been an objectlve to increase the range of colors that may be achieved with a given composition so that a variety of colors are available for use without the ~ !
necessity of prolonged durability testing for each new colored coating prior to its use. I
In U. S. Patent No. 3,467,508 Loukes st al teach a method of making colored glass articles. By modifying the surface of the glass substrate with selected metals, other than the tin which is normally present at the surface of float formed soda-lime-silica glass, it is possible to provide the glass with stained surface layers of various desired colors. Unfortu-nately, such ~etal modified glass surfaces, characterized in the art as ~L~6Z~69 "ion-exchanged" surfaces, are relatively soft and are easily damaged by mild abrasion. Therefore, it is practical to limit ; the use of such articles to interior appiications or use in double glazed windows where durability is not as critical as for exposed exterior surfaces.
Coatings made by the described pyrolytic techniques ! and stains made by the described "ion-exchange" technique yield colored articles wherein the colors depend on the composition of the coloring medium. In order to obtain different colors it is necessary to modify the components of the coloring medium.
i A preferable result would follow from the ability to utilize ~-the same basic composition to provide a variety of colors.
It is known that selectively reflecting and transmitting interference filters can be produced by using materials of widely different indices of refraction in multiple-layer films `~
of controlled thicknesses. Such multiple-layer films have been -designed to effectively filter out all but narrow bands of light having the desired dominant wavelengths. These prior art i multiple-layer films have usually been made by vaccum evaporation ;1 20 deposition techniques. Such evaporation deposition methods are not readily adaptable to continuously coating large sheets of glass for use as viewing enclosures in architectural applications.
On the other hand, pyrolytic techniques normally used to f.':~ .
continuously coat large sheets of glass are not particularly `~ suited to making multiple-layer films. Reheating would generally `~
be required between coating steps and this can easily cause -s distortion in both the glass and the previously applied layers of the final film. ~`
SUMMARY OP THE INVENTION
: .
In accordance with one aspect of the invention there is ' provided an article of manufacture for the selective transmittance of solar radiation over an extended spectral ~6zg6~
range comprising a glass substrate having a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth concentrated in a surface region of the glass substrate which concentration is greater at the surface than at the interior of the substrate and having a metal oxide overcoat of a metal selected from the group consisting of cobalt, iron, chromium, copper, manganese, nickel, vanadium, titanium and mixtures thereof applied to the surface. Y
In a further aspect of the invention there is provided a method of coating a glass subs~rate comprising the steps of: a) contacting a surface of the substrate with a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth at a sufficiently high temperature to provide for migration of the metal into the contacted surface and b) contacting the modified surface of the substrate with a coating composition containing a metal compound at a } ;~
sufficiently high temperature to convert the metal compound to a metal oxide by thermal reaction on contact with the glass substrate.
It will therefore be seen that the surface of a glass substrate is modified by dissolving at least one metal, other than or in addition to tin, into a surface of the glass `substrate. This modification is preferably accomplished by con~acting :
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~i2969 the glass surface with a pure metal or metal alloy under reducing conditions and at a temperature sufficient to permlt migration of the metal into the glass surface where it may be present in metallic form or incorporated into the oxide matrix of the glass. The modified surface, preferably while still at an elevated temperature and preferably after brief exposure to an oxidiz- -ing atmosphere, is contacted with a metal-containing coating composition under such conditions as to cause pyrolyzation of the coating composition and deposition of a metal oxide coating on the surface of the substrate.
The resultant articles exhibit increased solar energy control capabilities, improved durability, and flexibility in the selection of reflected and transmitted colors when compared with articles made by the techniques of the previously described references.
The present invention provides a method for producing metal oxide -- .
coated glass of surprisingly superior durability and, in addition, is capable , of providing a wide range of uniform colors heretofore unattainable by pyrolytic techniques.
Applying the method of the present invention allows one to produce certain uniform colors, previously obtainable only by interference techniques employing multiple-layer films, by using pyrolytic techniques. A single j coating may be employed to obtain a variety of color effects heretofore :
obtainable only with multiple-layer coatings, thereby eliminating significant ~ reheating costs. This single coating can be applied at the glass surface in ,, .
a continuous run procedure using pyrolysis for application of a metal oxide i film after dissolving a color imparting metal into the immediate surface of the glass substrate. In order to obtain articles having particular reflec-tance and transmittance characteristics and exhibiting desired color character-~-~ istics when viewed either in reflectance or transmittance, metals or combina-`i tions thereof having a particular index of refraction are selected and the ` , . ' .
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31L~62~69 thicknesses of the modified glass-metal layer and of the metal oxide film are controlled.
- ~ pure metal or metal alloy is dissolved into the surface of the glass matrix by maintaining molten, solid, or vaporized metal in contact with the glass surface at an elevated temperature, preferably -above the softening point of the glass and under reducing conditions. The dissolution of pure metal or metal alloy may be permitted to proceed by diffusion with thermal energy alone to enhance the rate of metal dissolution or the rate may be accelerated by electrochemical techniques such as by providing an electric potential across the contacting metal and the glass. -When an electric potential is used as the driving force, the metal or alloy is maintained on the surface of a glass substrate, which is to be modified, and another surface of the substrate is contacted with an electro-conductive material in an area opposite the metal or alloy.
The metal confined on the surface of the glass may be an alloy of tin, lead or bismuth. For example, the metal may be an alloy of tin with an .~ .
i element selected from the group of elements consisting of lithium, sodium, potassium, zinc, magnesium, vanadium, cobalt, nickel, copper, aluminum, ~ silicon, titanium, manganese, chromium and iron. The alloy may be an alloy `` ~ of tin with one of the rare earth metaIs. When employing a tin alloy, the ; relative concentration of the tin and the other metal and their relative i- chemical properties determines whether only the metal alloyed with the tin ~; enters the surface of the glass.
`-1 In other applications of the invention, the metal employed may be an alloy of bismuth or lead with an element selected from the group consisting of lithium, sodium, zinc, magnesium, vanadium, aluminum, silicon, ,~ titanium, manganese, chromium, iron, cobalt, nickel, copper, silver, gold, antimony, arsenic, and indium. Further, the metal may be an alloy of bismuth ., or lead with an element selected from the group consisting of the platinum .. ~ . ; .
~ ' ~
~CI 62969 group metals and the rare earth metals. The metal or metal alloy migrates into the glass matrix establishing a metal content in the glass which is greatest near th~ contacted surface and decreases toward the interior of the glass.
In preferred applications of the invention, the desired metal is confined on the surface of the substrate as a molten pool.
The surface of the glass which has been contacted with the metal is then contacted, while still at an elevated temperature, with a coating composition which pyrolyzes or otherwise reacts to form a metal oxide coating. This ~urther contacting may occur after a brief or a long exposure of the metal-containing glass to oxidizing conditions or may occur without interim oxidation.
The coating composition comprises a metal coating reactant which will pyrolyze or otherwise react to form a metal oxide coating upon contact with the glass and a solvent andlor a carrier gas for the coating reactants employed. The coating composition may be dispensed toward the glass as a liquid or vapor. ~ -Typical of the coating reactants which may be employed are organo-metallic salts lcnown in the coating art. Compounds such as acetatés, hexoates, and the like may be employed.
` While many organometallic salts, such as the acetates and 2-ethyl hexoates, are suitable to pyrolyze on contact with hot glass to form metal oxide films on the hot glass surface, superior films result from applying acetylacetonates of various metals in various relative concentrations in an organic vehicle to produce the desired colored appearance.
Various metal salts have well known film-forming properties. U. S.
Patent No. 3,244,547 to L. E. Orr et al., U. S. Patent No. 3j658,568 to Donley and U. S. Patent No. 2,564,708 show compositlons capable of forming ~.. ~''.
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~6Z~69 .
colored metal oxide films. However, to simplify storage and mixture problems, and to produce films having superlor durability, it is convenient to use a family of compositions containing one or more of the acetylacetonates of cobalt, iron and chromium.
Other pleaslngly colored coating compositions are produced by -using another family of compositions containing salts of one or more metals of the class consisting of copper, manganese and nickel. Still other suitable coloring compositions contain salts of one or more of any of the six metals enumerated above, as well as vanadium and titanium salts that form metal oxides by pyrolysis on contact with a glass surface. Other coatings, such as coatings comprising chromium oxide alone or in combination with iron oxide may , be effectively employed in this invention. For example, coatings comprising about 25 percent iron oxide and 75 percent chromium oxide deposited over clear or tinted glass containing copper in its surface region provide particularly ' desirable articles. ~ -¦ If a solvent is employed, as in the preferred embodiments, the solvent~should be relatively stable, non-explosive, have a high boiling polnt and not break down into corrosive products. Solvents which may be used to advantage include aliphatic and cyclic hydrocarbons, halocarbons and halo-genated hydrocarbons. Solvents, such as benzene and toluene, may be employed for economy although certain performance advantages accrue from the use of halogen-contalning materials as pointed out below.
Methylene chloride (CH2C12) is an excellent solvent for many organometallic salts used, has a sufficiently high boiling point to remain a liquid until it contacts the hot glass ribbon, and is sufficiently non-explosive and non-flammable to be safe for handling. Furthermore, this solvent appears to be chemically stable and does not break down into corrosive ! compounds such as HCl and methane.
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~6Z969 `
Seyeral other aliphatic and olefinic halocarbons and halogenated hydrocarbons meet these requirements. These include:
methylene bromide (CH2Br2) carbon tetrachloride (CC14) carbon tetrabromide (CBr4) chloroform (CHC13) bromoform (CHBr3) l,l,l-trichloroethane (C13C-CH3) perchloroethylene (C12C=CC12) Cl Cl l l 1,1,2~trichloroethane (H-C,~CI-H) Cl ~l dichloroiodomethane (CHC12I) Br Br 1,1,2-tribromoethane (H-C-C~H) Br H
trichloroethylene (C12C=CClH) tribromoethylene (Br2C=CBr.H) Cl trichloromonofluoromethane (F-C-Cl) ~ -: Cl . hexachloroethane (CI3C-CC13) : :
ljl,l,2-tetrachloro-2-fluoroethane (C13C-CHClF) ; 1,1,2-trichloro~1,2~difluoroethane (FC12C~CHClF) tetrafluorobromoethane (F3C-CFBrH) or (F2BrC-CF2H) hexachlorobutadiene (CC12=CCI-CCl=CC12) and tetrachloroethane (C12HC-CHC123 - :: :
: ' In addition, mlxtures of two or more of the aforesaid organic solvents ,....
. which are compatible may be used.
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~Çi2969 Other solvents having superior dissolving power for the metal salts used, such as various mixtures of one or more organic polar compounds, such as an alcohol containing one to four carbon atoms and one hydroxyl group, or one or more aromatic non-polar compounds taken from the class consisting of benzene, toluene and xylene may be used with caution. However, their volatility makes them more difficult to handle than the solvents listed above.
This invention may be advantageously carried out in conjunction with a process for forming flat glass by floating it on molten tin. After the glass being formed has assumed a dimensionally stable configuration on a pool of molten tin, it is contacted on its top~surface with a pure metal or a metal alloy which migrates into the surface of the glass. The rate of migration may be accelerated by externally applied electrochemical forces. After leaving the float chamber, the surface of the glass which has been contacted by the metal is then contacted with a metal-containing coating composition while the glass temperature is maintained sufficiently high to cause pyrolysis of the coatlng composition. The glass may be subjected to an oxidi~ing atmosphere between the steps of metal migration and metal oxide~coating and this is preferred to further enhance the dura-bility of the resulting film. Apparatus for applying a metal oxide coating to the glass emerging from a float chamber is illustrated and described in U. S. Patents Nos. 3,660,061 and 3,689,304. If an annealed final product is desired, coating is accomplished by immediately spraying the glass ribbon with the metal oxide forming solution within seconds after it leaves the float forming chamber. The coated, annealed ribbon is then cut to the desired dimensions. If a tempered or heat strengthened product is desired, the heating and coating steps may be performed subsequent to the forming of glass or in a separate operation.
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; ~62~69 '~ .This method resul~s in an article which exhibits exceptional durability an~ also provides a wide variety of colors by reflectance and transmittance. The metal that is dispersed into the immediate surface layer of the glass substrate is relatively concentrated in the first micron or two beneath the surface. In general, this concentration gradually decreases until at a depth of about 12 to 14 microns there is only a trace of metal. The result is an alteration of the index of refraction at the ., .
glass surface while not affecting that of the remainder of the substrate.
The standard glass composition and the comparatively very thin comixture of glass and metal have distinctively different indices of refraction.
Coating such a modified surface of a glass substrate with a metal oxide ~, film produces ~wo unexpected results.
First is an unexpected increase in durability. The glass surface .~ .
as modified by the addition of metal is relatively soft and can be easily removed by mild abrasion. The described metal oxide films, when applied directly to an unmodified surface of a glass substrate, are durable and may be used in single gla~ed architectural applications. However, the combination of a durable metal oxide film and a soft, non-durable surface-modified substrate yields a product having significantly increased durability over one produced by applying the same metal oxide to a non-modified glass - ;
substrate, even one containing tin in its surface regions by virtue of its manufacture by floating on tin prior to coating.
, . .
Second, the present invention allows the production of a variety of uniform colors with each coating composition employed. Such a variety of colors from a~ single composition had previously been unattainable by conventional pyrolytic techniques. In order to obtain a variety of colors by interference techniques, it is necessary to use two or more coatings, each of fixed composition having widely different indices of refraction in , -- 10 --, . ...
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~CI 62~169 alternate layers to provide multiple-layer films having optical thickness of approximately one-quarter of the wavelength of the visible light to be selectively reflected. The optical thickness of a film is defined as the actual thickness times the index of refraction. The median wavelength of the visible range is approximately 5,800 angstroms (580 nm). Therefore, in order to obtain interference colors having approximately this dominant wavelength, the optical thickness of the film should be approximately 1,450 angstroms (145 nm).
The bulk index of refraction of common glass is about 1.52. This value will vary slightly with composition, but remains essentially in the range of from 1.50 to 1.56 for such common glasses as soda-lime glasses.
The bulk index of refraction of the metal oxides used for the coatings in the present invention vary from about 2.0 to 3Ø The measured index of refraction of thin pyrolytic films is lower than the bulk index of refraction, but as the thickness of~a film is increased, void spaces in the film become filled and the index of refraction of the film approaches the bulk value for the metal oxide comprising the film. Metal oxide films at least 600-800 angstroms (60-80 nm) thick deposited on ordinary glass are observed to dis-play interference colors. However, it is difficult to produce pyrolytic films of this threshold thickness and maintain uniformity. Furthermore, .
the presence of interference colors accentuates the non-unlformity of the film.
By modifying the surface of the glass substrate to increase the index of refraction of the substrate, it is possible to produce-uniform colors, such as those produced by interference, using metal oxide films of less than one-quarter wavelength optical thickness. This result is unique in that such colors cannot be produced by applying thin films to normal tinted glasses or to the tin-enriched surface of float glass. Thls may be . ` .
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~a362~69 due to the fact that in neither process is there a significant increase in index of refraction over that of clear glass produced by conventional methods. The glass composition remains essentially unchanged with the tint being derived from the addition of a small concentration of colorant which is uniformly distributed throughout the entire thickness of the glass.
Concentrations of colorant as high as one percent are not uncommon in -commercially available tinted glasses. However, the concentratio`n is rela-tively constant throughout the glass, and metal oxide coatings on such glasses reflect a color that is essentially the same as that of the same coating on clear glass.
The invention will be more fully understood from the detailed descriptions of the preEerred embodiments which follow.
i! .. ' Description of the Preferred Embodiments .
Soda~lime-silica glass is prepared by compounding raw materials, melting them to form molten glass and refining the molten glass according to known techniques. Soda-lime-silica glasses normally contain by weight about 60 to 75 percent SiO2; 10 to 15 percent Na20; 0 to 5 percent K20, the sum of Na20 plus K20 being 10 to 15 percent; 5 to 15 percent CaO; O to 10 percent MgO, the sum of CaO and MgO being 5 to 15 percent; O to 1 percent A1203 and minor amounts of other ingredients for fining and coloring the glass. Examples of colored lime-soda-silica glasses are described in U. S.
, Patent Nos. Re. 25,31Z and 3,296,004.
; The process can be carried out by treating glass made by any - of the standard known flat glass processes such as float, sheet or plate ; glass. However, the float process is preferred.
; This invention may be further appreciated by reference to the following examples.
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j - 12 -~6Z~69 EXAMPLE I
Flat glass having the following approximate composition is produced - by floating the glass on molten tin in a reducing atmosphere containing tin vapors.
Percent by Weight SiO2 72.0 Na2O 13.3 K2O 0.6 CaO 8.9 MgO 3.8 12O3 1.0 3 0.3 Fe203 0 .10 ¦ The glass produced in accordance with this method has an equilib-j rium thickness of approximately one-quarter inch or seven millimeters.
Thls equilibrium thickness glass was used for all of the experiments described in the present examples.
! ~ During formation~ tin enters both the top surface and the bottom surface of the glass. The top surface of the glass is exposed during forming ~ to a gaseous atmosphere containing tin vapor in addition to nitrogen and -J~ hydrogen which fills the space in a forming chamber above the pool of molten tin on which the glass is floated to form it into flat glass. Ihe bottom surface of the glass rests directly on the pool of molten tin. The average temperature of the molten tin is from about 1400F. to about 1600F. The ~`~ glass is present in the tin-containing forming chamber for a period of from about 5 minutes to about 15 minutes.
In the forming chamber the top surface of the glass lS contacted ~ with a pool of molten copper and lead comprising about 2 percent by weight .,~
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1C36Z~;9 copper and about 98 percent by weight lead. An electric current is passed through the glass between the pool of the copper-lead alloy and the underlying pool of tin. Copper and lead are driven into the glass through its top surface. ' Presumably, some of the tin which has been dissolved into the surface during the float process and the alkali metals present at the surface in the glass matrix are driven from the glass. The lead ions, probably due to their size, re~
main essentially at the surface. The depth of copper ,~
penetration can be increased with an increase in voltage i~
across the system, but it too remains concentrated near the i' -surface. Variation of color by reflectance and transmittance can be attained by controlling the voltage in order to ~, produce a desired concentration and depth of penetration of the exchange metal or metal alloy. This is essentially the ' process described in U.S. Patent No. 3,467,508 to Loukes et al.
The resulting glass is removed and cooled without further treatment and analyzed by conventional electron probe techniques and exhibits copper and lead concentrations as shown here in percents by weight. Table I summarizes ;.'~
the properties of a colored glass substrate stained by the described surface modification method.
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TABLE I
Depth Beneath Top Surface (Microns) Percent Cu Percent Pb 1.5 1.3 2.0 2.5 1.2 0.17 3.5 0.73 0.04
4.5 0.35 0
5.5 0.33 e 6.5 7.5 . 0.36 8.5 0.37 9 5 0.36 10.5 0.37 'l 11.5 0.29 12.5 0.21 13.5 0.10 14.5 0.06 , The table clearly indicates that essentially all of the dissolved , lead remains at the immediate glass surface, penetrating to a depth of about 1.5 to 2.0 microns, while the dissolved copper penetrates into the glass sub- -strate to a depth of about 10 to 12 microns, ~eyond which only trace amounts ~, of the metal are found. Although so~e tin may be driven out by dissolving lead and copper, the surface region of the glass substrate remains tin-enriched in comparison with the interior region. Approximately 0.01 to 0.1 percent tin remains in the surface region of the glass substrate.
The metal alloy is highly concentrated at the contacted surface and does not diffuse through the entire thickness of the glass. It is this high concentration of metal acting as a stain that imparts the color and spectral characteristics to the modified substrate. The glass thus modified differs from commonly known-tinted or colored glasses in that it . ~1 .
~ obtains its color because of this high concentration of metal at the glass ., .
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1~6Z969 :;
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surface rather than a relatively uniform concentration of colorant through-out the thickness of the glass substrate. :
The surface modified glass has the following spectral properties ;: :
with light incident to the modified surface: :
TABLE II
TRANSMITTANCE PROPEP~TIES
Luminous transmittance (percent) 49.2 :
:' Ultraviolet transmittance (percent) 16.2 Infrared transmittance (percent) , 64.7 :
Total solar energy transmittance (percent) 55.8 Dominant transmitted wavelength (nanometers) 577.7 Excitation purity (percent) 17.65 Index of Refraction (apparent)* 1.33 .
~ Extinction Coefficient (apparent)* 0.64 $ , .
$: * Although chese values are based upon elipsometer measure-ments at the mercury vapor greenline of 546.1 nm, they 1 : are apparent values since the surface modified Layer is 7 not of infinite thickness compared to the penetration of . the light and is not of uniform composition as evidenced : :
in Table I. - ~ ~.
REFLECTANCE PROPERTIES
., , Luminous~reflectance (percentj . 11.10 . ~ .
i~ : Ultraviolet reflectance (percent) 4.22 ;l Infrared reflectance (percent) 10.14 ~j Total solar energy reflectance (percent) 10.20 - :
,J Dominant reflected wavelength (nanometers) 576.08 . ~ Bxcitation purity (percent) L5.75 . . ~
-.
1CI362~69 Several sheets of the surface modified glass are heated to about 1100F.
in air and sprayed with solutions consisting of approximately 2 percent by weight metal in a methylene chloride solvent. Stock solutions of the metal containing composition are prepared by dissolving approximately one pound (4$4 grams) of metal acetylacetonate in one gallon (3.78 liters) of methylene chloride resulting in the 2 percent by weight metal solution.
These solutions were then sprayed against selected hot glass sheets either separately or as mixtures proportioned as follows:
METAL COMPONENTS ~2% by SPRAY SOLUTIONWeight in Solutlon) ~~
Al00 percent cobalt acetylacetonate ~100 percent iron acetylacetonate C100 percent chromium acetylacetonate D70 percent iron acetylacetonate and 30 percent nickel acetylacetonate E100 percent tltanium acetylacetonate , The resulting coated sheets of glass have the following spectral l~ properties with light incident to their coated surfaces. -i f :' , . . .
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TABLE III
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TRANSMITTANC~ PROPERTIES
I.uminous transmittance (%)29 28 43 39 52 Ultraviolet transmittance (%) 6 2 5 5 17 ~, Infrared transmittance (%) 50 54 55 63 65 TSE transmittance (%) 38 41 48 50 57 Dominant wavelength (nanometers) 581 581 578 579 577.3 Excitation purity (%) 39 50 32 40.7 15.7 , REFLECTANCE PROPERTIES
i Luminous reflectance ~%) 24 44 21 23 8 `l Ultraviolet reflectance (%)22 40 55 33 11 1 Infrared reflectance (%) 17 18 12 12 10 ~ .
TSE reflectance (%) 21 21 19 18 9 ~' Domlnant wavelength (nanometers) 492 483 472 480 577.4 Excitation purity (%) 3.313 25 12.6 41.1 :j . ,.
~ These characteristics can be easily modified by changing the film ;~ compositions and thicknesses to yield a broad range of desirable colors. -~` All of the samples perform satisfactorily in standard Federal Testing Nethod cyclic humidity (FTM 810B) and 5% salt spray (FTM 151A) tests. They show little or no deterioration after over 1400 hours of each test. This ,l is especially significant in the case of cobalt oxide films (Sample A) ' which fail within 24 hours of exposure to salt spray testing when applied ! to standard plate, sheet, or float glasses.
The uncoated surface modified glasses also perform equally well in these two tests. However, when tested for abFasion resistaDce, the .
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~L~6~969 colored modified surfaces are easily removed from rhese uncoated samples with only light abrasion of the surface with pumice or cerium dioxide.
The samples with an overcoat of metal oxide on the modified surface, Samples A through E, withstand vigorous abrading with the above two agents and show no sign of deterioration following prolonged rubbing with pumice.
The metal oxide overcoat provides significantly increased abrasion resistance compared with the metal-modi~ied surface and provides colors not available using solely the surface modification process or known pyrolytic techniques. The combination of the modified surface and the pyrolytic metal oxide coating provides a means for obtaining a variety of uniform colors which have not heretofore been attainable with fixed coatlng composi~ions except by the interference technique employing multiple-layer films.
In addition to improved durability and increased color flexibility, the metal oxide coated glass demonstrates improved solar energy control capabilities over that Df the uncoated surface-modifled glass as can be `
seen by a comparison of Tables II and III. Except for Sample E, a titanium oxide overcoat, total solar enerey transmiteance is decreased and total solar energy reflectance is increased at least twofold. This means that ~ ;
less heat is transmitted directly to an enclosed space within a building glazed with the articles of this invention and significantly less solar energy is absorbed by such glass articles. This heIps to alleviate the problem of thermal breakage encountered when using high solar energy absorb-ing glasses in architectural applications.
.. . .
EXAMPLE II
An additional sample of the surface-modified glass is prepared according to the procedure of Example 1. The resultant modified glass sheets have the following spectral properties with light incident to their . :
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modified surfaces. The transmittance properties were approximately the same as the glass of Example I although the reflectance properties differ for this sample of gla~s. It is believed that the copper may be more concentrated in the extreme surface region of this glass.
TABLE IV
TR~NSMITTANCE PROPERTIES
Luminous transmittance (percent) 44.88 Ultraviolet transmittance (percent~ 17.34 Infrared transmittance (percent) 65.27 Total solar energy transmittance (percent) 54.13 Dominant transmitted wavelength (nanometers) 580.88 Excitation puri~y (percent) 11.99 Index of refraction (apparent)* ~1.4 , ~' : REFLECTANCE PROPERTIES
~, ~ Luminous reflectance (percent) 23.35 . ~ ~ :
Ultraviolet reflectance (percent) 11.58 Infrared reflectance (percent) 6.84 Total solar energy reflectance (percent)~ 14.28 I: ~ :
`~ Dominant reflected wavelength ~nanometers) 562.86 :
Excitation purity (percent) 8.19 ~ * Estimated from luminous transmittance value.
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The metal-modified surface is removed by light abrasion with ~'; pumice and ceri~m dioxide from 4 inch by 6 inch sections oE several ~ 12 inch by 12 inch sheets of the above modified glass. The partially -~ abraded sheets are then heated to about 1100F. and sprayed with similarly , produced metal oxide film-forming solutions according to the procedure . I .
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\
~96Z~69 described in Example I. A metal oxide coating was Eormed on both the abraded and unabraded glass surfaces. The coating solutions utilized `
had the following metal composition: .
.
METAL COMPONENTS (2% by SPRAY SOLUTION . Weight in Solution) A 70 percent iron acetylacetonate and 30 percent nickel acetylacetonate B 30 percent cobalt acetylacetonate, 30 percent iron acetylacetonate and ~:~ 40 p'ercent chromium acetylacetonate The coated sheets were tested to determine the spectral properties . .
of the coatings on the unabraded modified surfaces.
: TABLE V
: ~ TRANSMITTANCE COATED MODIFIED SURFACE
,, A_ B - ~ :
Luminous transmittance (percent) : 39.01 40.31 Ultraviolet transmittance (percent) 6.. 16 11.82 st~ Infrared transmittance ~percent) 59.26 61.20 , Total Solar energ~y transmittance (percent) 46.40 48.92 Dominant wavelength (nanometers) 575.93 576.90 Excitation purity (percent) 32.28 .14.11 : REFLECTANCE
:j: , : Luminous reflectance (percent) 21.81 20.95 , Ultraviolet reflectance (percent) 24.94 12.16 ' Infrared reflectance (percent) 14.41 10.63 Total solar energy reflectance (percent) 19.90 15.83 : Dominant wavelength (nanometers) -605.24 577.96 Excitation purity (percent) . 9.67 43.89 :i . ,~ , . . : , . , : .:
~ Z969 The glass coated with spray solution A is substantially the same as the glass of Example I coated with spray solution D of that examp].e except that its coating is on the order of 500 angstroms (50 nanometers) thick which is about 200 angstroms (20 nanometers) thicker than the coating of Example I-A. It may be noted that, except for the hue or dominant wavelength of the reflected color, the properties of the coated glass of this Example (A~ are substantially the same as those of the coated glass of Example I(D). The apparent color or hue Oe a coated glass article may thus be altered by merely altering the thickness of the coating on the glass while maintaining the CompOSitiOn of the coating unchanged.
For all coated sheets of glass, the metal oxide coating on the 4 inch by 6 inch area where the modified surface has been removed by abrasion --, is 95 percent removed in a period from about 4 hours to 4 days when subjected to the 5 percent salt spray test. The metal oxide coatings applied to the unabraded surface show little degradation after over 1400 hours of the salt spray test.
, EXAMPLE III
I An additional sample is prepared in accordance with the procedure ! ~ . . ..
of Example I escept that silver was alloyed with the lead in lieu of copper and dissolved into the glass surface as described. This sample and samples of clear float glass and the copper-lead surface-modified glass are then coated with a 2 percent solution of cobalt acetylacetonate as described in Example I. The cobalt oxide fi:Lm on the clear float glass begins to fail within four hours and is severely degraded in just a few days of accelerated testing using the standard 5 percent salt spray test. Both the copper and silver modified surfaces coated with the cobalt oxide perform well and show no attack after over 1600 hours of accelerated testing. These results clearly indicate the increased durability of the metal oxide coating when combined ., .
. :
, 1¢~6Z~6~
with a metal-modified surface of glass to produce the-articles of the present invention.
The form of the invention shown and described in this disclosure represents certain illustrative embodiments. It is llnderstood that various useful embodiments may be made without departing from the spirit oE 'his inyentlon ': , ,: .
' ~ , . . .
, . ' ' ' ~
. ~ ' ' ' , .
:1 i , . :: ; ; : :
The metal alloy is highly concentrated at the contacted surface and does not diffuse through the entire thickness of the glass. It is this high concentration of metal acting as a stain that imparts the color and spectral characteristics to the modified substrate. The glass thus modified differs from commonly known-tinted or colored glasses in that it . ~1 .
~ obtains its color because of this high concentration of metal at the glass ., .
~ - 15 -.~. . . . . . . ..
1~6Z969 :;
. ..
.
surface rather than a relatively uniform concentration of colorant through-out the thickness of the glass substrate. :
The surface modified glass has the following spectral properties ;: :
with light incident to the modified surface: :
TABLE II
TRANSMITTANCE PROPEP~TIES
Luminous transmittance (percent) 49.2 :
:' Ultraviolet transmittance (percent) 16.2 Infrared transmittance (percent) , 64.7 :
Total solar energy transmittance (percent) 55.8 Dominant transmitted wavelength (nanometers) 577.7 Excitation purity (percent) 17.65 Index of Refraction (apparent)* 1.33 .
~ Extinction Coefficient (apparent)* 0.64 $ , .
$: * Although chese values are based upon elipsometer measure-ments at the mercury vapor greenline of 546.1 nm, they 1 : are apparent values since the surface modified Layer is 7 not of infinite thickness compared to the penetration of . the light and is not of uniform composition as evidenced : :
in Table I. - ~ ~.
REFLECTANCE PROPERTIES
., , Luminous~reflectance (percentj . 11.10 . ~ .
i~ : Ultraviolet reflectance (percent) 4.22 ;l Infrared reflectance (percent) 10.14 ~j Total solar energy reflectance (percent) 10.20 - :
,J Dominant reflected wavelength (nanometers) 576.08 . ~ Bxcitation purity (percent) L5.75 . . ~
-.
1CI362~69 Several sheets of the surface modified glass are heated to about 1100F.
in air and sprayed with solutions consisting of approximately 2 percent by weight metal in a methylene chloride solvent. Stock solutions of the metal containing composition are prepared by dissolving approximately one pound (4$4 grams) of metal acetylacetonate in one gallon (3.78 liters) of methylene chloride resulting in the 2 percent by weight metal solution.
These solutions were then sprayed against selected hot glass sheets either separately or as mixtures proportioned as follows:
METAL COMPONENTS ~2% by SPRAY SOLUTIONWeight in Solutlon) ~~
Al00 percent cobalt acetylacetonate ~100 percent iron acetylacetonate C100 percent chromium acetylacetonate D70 percent iron acetylacetonate and 30 percent nickel acetylacetonate E100 percent tltanium acetylacetonate , The resulting coated sheets of glass have the following spectral l~ properties with light incident to their coated surfaces. -i f :' , . . .
: : .
~ ~ , ' . .
.
, - . ' .
:, . .. . : . . : i~ .: . .
`':'; ~ , ' "' ' ' , , '~ ' ; " ' : ; `'' '. .' ' ~6Z9~9 . .
. .
TABLE III
. .....
r, Coated Glass with Solution A B C D E
TRANSMITTANC~ PROPERTIES
I.uminous transmittance (%)29 28 43 39 52 Ultraviolet transmittance (%) 6 2 5 5 17 ~, Infrared transmittance (%) 50 54 55 63 65 TSE transmittance (%) 38 41 48 50 57 Dominant wavelength (nanometers) 581 581 578 579 577.3 Excitation purity (%) 39 50 32 40.7 15.7 , REFLECTANCE PROPERTIES
i Luminous reflectance ~%) 24 44 21 23 8 `l Ultraviolet reflectance (%)22 40 55 33 11 1 Infrared reflectance (%) 17 18 12 12 10 ~ .
TSE reflectance (%) 21 21 19 18 9 ~' Domlnant wavelength (nanometers) 492 483 472 480 577.4 Excitation purity (%) 3.313 25 12.6 41.1 :j . ,.
~ These characteristics can be easily modified by changing the film ;~ compositions and thicknesses to yield a broad range of desirable colors. -~` All of the samples perform satisfactorily in standard Federal Testing Nethod cyclic humidity (FTM 810B) and 5% salt spray (FTM 151A) tests. They show little or no deterioration after over 1400 hours of each test. This ,l is especially significant in the case of cobalt oxide films (Sample A) ' which fail within 24 hours of exposure to salt spray testing when applied ! to standard plate, sheet, or float glasses.
The uncoated surface modified glasses also perform equally well in these two tests. However, when tested for abFasion resistaDce, the .
, ... .
: ' "':, . .
.. ; . .
~L~6~969 colored modified surfaces are easily removed from rhese uncoated samples with only light abrasion of the surface with pumice or cerium dioxide.
The samples with an overcoat of metal oxide on the modified surface, Samples A through E, withstand vigorous abrading with the above two agents and show no sign of deterioration following prolonged rubbing with pumice.
The metal oxide overcoat provides significantly increased abrasion resistance compared with the metal-modi~ied surface and provides colors not available using solely the surface modification process or known pyrolytic techniques. The combination of the modified surface and the pyrolytic metal oxide coating provides a means for obtaining a variety of uniform colors which have not heretofore been attainable with fixed coatlng composi~ions except by the interference technique employing multiple-layer films.
In addition to improved durability and increased color flexibility, the metal oxide coated glass demonstrates improved solar energy control capabilities over that Df the uncoated surface-modifled glass as can be `
seen by a comparison of Tables II and III. Except for Sample E, a titanium oxide overcoat, total solar enerey transmiteance is decreased and total solar energy reflectance is increased at least twofold. This means that ~ ;
less heat is transmitted directly to an enclosed space within a building glazed with the articles of this invention and significantly less solar energy is absorbed by such glass articles. This heIps to alleviate the problem of thermal breakage encountered when using high solar energy absorb-ing glasses in architectural applications.
.. . .
EXAMPLE II
An additional sample of the surface-modified glass is prepared according to the procedure of Example 1. The resultant modified glass sheets have the following spectral properties with light incident to their . :
,.: ,, . . f ~ ....................... .. . .~ , ..
, :: . . ~ . , : ,: ~.
1C1~6296~ :
,:
modified surfaces. The transmittance properties were approximately the same as the glass of Example I although the reflectance properties differ for this sample of gla~s. It is believed that the copper may be more concentrated in the extreme surface region of this glass.
TABLE IV
TR~NSMITTANCE PROPERTIES
Luminous transmittance (percent) 44.88 Ultraviolet transmittance (percent~ 17.34 Infrared transmittance (percent) 65.27 Total solar energy transmittance (percent) 54.13 Dominant transmitted wavelength (nanometers) 580.88 Excitation puri~y (percent) 11.99 Index of refraction (apparent)* ~1.4 , ~' : REFLECTANCE PROPERTIES
~, ~ Luminous reflectance (percent) 23.35 . ~ ~ :
Ultraviolet reflectance (percent) 11.58 Infrared reflectance (percent) 6.84 Total solar energy reflectance (percent)~ 14.28 I: ~ :
`~ Dominant reflected wavelength ~nanometers) 562.86 :
Excitation purity (percent) 8.19 ~ * Estimated from luminous transmittance value.
,, ~ .
The metal-modified surface is removed by light abrasion with ~'; pumice and ceri~m dioxide from 4 inch by 6 inch sections oE several ~ 12 inch by 12 inch sheets of the above modified glass. The partially -~ abraded sheets are then heated to about 1100F. and sprayed with similarly , produced metal oxide film-forming solutions according to the procedure . I .
: "
\
~96Z~69 described in Example I. A metal oxide coating was Eormed on both the abraded and unabraded glass surfaces. The coating solutions utilized `
had the following metal composition: .
.
METAL COMPONENTS (2% by SPRAY SOLUTION . Weight in Solution) A 70 percent iron acetylacetonate and 30 percent nickel acetylacetonate B 30 percent cobalt acetylacetonate, 30 percent iron acetylacetonate and ~:~ 40 p'ercent chromium acetylacetonate The coated sheets were tested to determine the spectral properties . .
of the coatings on the unabraded modified surfaces.
: TABLE V
: ~ TRANSMITTANCE COATED MODIFIED SURFACE
,, A_ B - ~ :
Luminous transmittance (percent) : 39.01 40.31 Ultraviolet transmittance (percent) 6.. 16 11.82 st~ Infrared transmittance ~percent) 59.26 61.20 , Total Solar energ~y transmittance (percent) 46.40 48.92 Dominant wavelength (nanometers) 575.93 576.90 Excitation purity (percent) 32.28 .14.11 : REFLECTANCE
:j: , : Luminous reflectance (percent) 21.81 20.95 , Ultraviolet reflectance (percent) 24.94 12.16 ' Infrared reflectance (percent) 14.41 10.63 Total solar energy reflectance (percent) 19.90 15.83 : Dominant wavelength (nanometers) -605.24 577.96 Excitation purity (percent) . 9.67 43.89 :i . ,~ , . . : , . , : .:
~ Z969 The glass coated with spray solution A is substantially the same as the glass of Example I coated with spray solution D of that examp].e except that its coating is on the order of 500 angstroms (50 nanometers) thick which is about 200 angstroms (20 nanometers) thicker than the coating of Example I-A. It may be noted that, except for the hue or dominant wavelength of the reflected color, the properties of the coated glass of this Example (A~ are substantially the same as those of the coated glass of Example I(D). The apparent color or hue Oe a coated glass article may thus be altered by merely altering the thickness of the coating on the glass while maintaining the CompOSitiOn of the coating unchanged.
For all coated sheets of glass, the metal oxide coating on the 4 inch by 6 inch area where the modified surface has been removed by abrasion --, is 95 percent removed in a period from about 4 hours to 4 days when subjected to the 5 percent salt spray test. The metal oxide coatings applied to the unabraded surface show little degradation after over 1400 hours of the salt spray test.
, EXAMPLE III
I An additional sample is prepared in accordance with the procedure ! ~ . . ..
of Example I escept that silver was alloyed with the lead in lieu of copper and dissolved into the glass surface as described. This sample and samples of clear float glass and the copper-lead surface-modified glass are then coated with a 2 percent solution of cobalt acetylacetonate as described in Example I. The cobalt oxide fi:Lm on the clear float glass begins to fail within four hours and is severely degraded in just a few days of accelerated testing using the standard 5 percent salt spray test. Both the copper and silver modified surfaces coated with the cobalt oxide perform well and show no attack after over 1600 hours of accelerated testing. These results clearly indicate the increased durability of the metal oxide coating when combined ., .
. :
, 1¢~6Z~6~
with a metal-modified surface of glass to produce the-articles of the present invention.
The form of the invention shown and described in this disclosure represents certain illustrative embodiments. It is llnderstood that various useful embodiments may be made without departing from the spirit oE 'his inyentlon ': , ,: .
' ~ , . . .
, . ' ' ' ~
. ~ ' ' ' , .
:1 i , . :: ; ; : :
Claims (17)
1. A method of coating a glass substrate comprising the steps of:
a. contacting a surface of the substrate with a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth at a sufficiently high temperature to provide for migration of the metal into the contacted surface and b. contacting the modified surface of the sub-strate with a coating composition containing a metal compound at a sufficiently high temperature to convert the metal com-pound to a metal oxide by thermal reaction on contact with the glass substrate.
a. contacting a surface of the substrate with a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth at a sufficiently high temperature to provide for migration of the metal into the contacted surface and b. contacting the modified surface of the sub-strate with a coating composition containing a metal compound at a sufficiently high temperature to convert the metal com-pound to a metal oxide by thermal reaction on contact with the glass substrate.
2. The method according to Claim 1 wherein the glass substrate is formed by floating molten glass on a pool of molten tin-containing metal, the contacting of the surface of the substrate with the pure metal or metal alloy being ac-complished after the glass has achieved a dimensionally stable configuration on the pool of molten tin-containing metal.
3. The method according to Claim 1, wherein the glass substrate is a flat glass substrate.
4. The method according to Claim 1, wherein the color imparting metal is a molten alloy of tin and an element selected from the group consisting of lithium, sodium, potas-sium, zinc, magnesium,aluminum, silicon, titanium, manganese, chromium, iron and the rare earth metals.
5. The method according to Claim 1, wherein the metal is a molten alloy of bismuth with an element selected from the group consist-ing of lithium, sodium, zinc, magnesium, aluminum, silicon, titanium, manganese, chromium, iron, cobalt, nickel, copper, silver, gold, anti-mony, arsenic, indium, the platinum group metals and the rare earth metals.
6. The method according to Claim 1, wherein the metal is a molten alloy of lead with an element selected from the group consisting of lithium, sodium, zinc, magnesium, aluminum, silicon, titanium, man-ganese, chromium, iron, cobalt, silver, nickel, copper, gold, antimony, arsenic, indium, the platinum group metals and the rare earth metals.
7. The method according to Claim 1, wherein the coating com-position contains a metal compound of a metal selected from the group consisting of cobalt, iron, chromium, copper, manganese, nickel, vana-dium, and titanium and mixtures thereof.
8. The method according to Claim 1, wherein the glass is a soda-lime-silica glass.
9. The method according to Claim 1, wherein the substrate is exposed to an oxidizing atmosphere between the steps of surface modifi-cation and metal oxide coating.
10. The method according to Claim 1, wherein an electroconductive material is provided on the surface of the substrate opposite the surface contacted by the metal and an electric current is passed through the sub-strate between the metal and the electroconductive material.
11. An article of manufacture for the selective transmittance of solar radiation over an extended spectral range comprising a glass substrate having a color imparting pure metal or metal alloy selected from the group consisting of tin, lead and bismuth concentrated in a surface region of the glass substrate which concentration is greater at the surface than at the interior of the substrate and having a metal oxide overcoat of a metal selected from the group con-sisting of cobalt, iron, chromium, copper, manganese, nickel, vanadium, titanium and mixtures thereof applied to the surface.
12. The article of manufacture according to Claim 11, wherein said glass substrate is a flat glass substrate.
13. The article according to Claim 11, wherein said alloy is an alloy of tin with an element selected from the group consisting of lithium, sodium, potassium, zinc magnesium, aluminum, silicon, titanium, manganese, chromium, iron and the rare earth metals.
14. The article according to Claim 11, wherein said alloy is an alloy of bismuth with an element selected from the group consisting of lithium, sodium, zinc, magnesium, aluminum, silicon, titanium, manganese, chromium, iron, cobalt, nickel, copper, silver, gold, antimony, arsenic, indium, the platinum group metals and the rare earth metals.
15. The article according to Claim 11, wherein said alloy is an alloy of lead with an element selected from the group consisting of lithium, sodium, zinc, magnesium, aluminum, silicon, titanium, manganese, chromium, iron, cobalt, silver, nickel, copper, gold, antimony, arsenic, indium, the platinum group metals and the rare earth metals.
16. The article according to Claim 11, wherein said alloy con-centrated at the said glass surface is a copper-lead alloy.
17. The article according to Claim 11, wherein said glass sub-strate is a soda-lime-silica glass.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US54408175A | 1975-01-27 | 1975-01-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1062969A true CA1062969A (en) | 1979-09-25 |
Family
ID=24170668
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 240560 Expired CA1062969A (en) | 1975-01-27 | 1975-11-26 | Coating glass |
Country Status (11)
| Country | Link |
|---|---|
| JP (1) | JPS51111818A (en) |
| AU (1) | AU500451B2 (en) |
| BE (1) | BE837894A (en) |
| BR (1) | BR7600062A (en) |
| CA (1) | CA1062969A (en) |
| DE (1) | DE2602256A1 (en) |
| DK (1) | DK159550C (en) |
| FR (1) | FR2298519A1 (en) |
| GB (1) | GB1517845A (en) |
| IT (1) | IT1055764B (en) |
| SE (1) | SE447373B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53141318A (en) * | 1977-05-17 | 1978-12-09 | Nippon Sheet Glass Co Ltd | Heat radiation reflecive glass |
| US4239816A (en) * | 1978-12-01 | 1980-12-16 | Ppg Industries, Inc. | Organic additives for organometallic compositions |
| JPS6018090B2 (en) * | 1979-10-03 | 1985-05-08 | 日本板硝子株式会社 | Method of forming conductive thin film |
| US4786784A (en) * | 1987-02-17 | 1988-11-22 | Libbey-Owens-Ford Co. | Method for producing an electrically heated window assembly and resulting article |
| FI123798B (en) * | 2007-04-23 | 2013-10-31 | Beneq Oy | Energy saving glass and a method of making it |
| CN113480192B (en) * | 2021-06-29 | 2023-04-11 | Oppo广东移动通信有限公司 | Preparation method of glass shell, glass shell and electronic equipment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5227645B2 (en) * | 1972-12-07 | 1977-07-21 |
-
1975
- 1975-11-26 CA CA 240560 patent/CA1062969A/en not_active Expired
- 1975-12-10 AU AU87421/75A patent/AU500451B2/en not_active Expired
-
1976
- 1976-01-08 BR BR7600062A patent/BR7600062A/en unknown
- 1976-01-09 IT IT6703976A patent/IT1055764B/en active
- 1976-01-15 FR FR7600950A patent/FR2298519A1/en active Granted
- 1976-01-22 DE DE19762602256 patent/DE2602256A1/en not_active Ceased
- 1976-01-23 GB GB258376A patent/GB1517845A/en not_active Expired
- 1976-01-23 SE SE7600715A patent/SE447373B/en not_active IP Right Cessation
- 1976-01-26 BE BE163787A patent/BE837894A/en not_active IP Right Cessation
- 1976-01-26 JP JP742876A patent/JPS51111818A/en active Pending
- 1976-01-26 DK DK29776A patent/DK159550C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| DK159550C (en) | 1991-04-02 |
| AU8742175A (en) | 1977-06-16 |
| GB1517845A (en) | 1978-07-12 |
| AU500451B2 (en) | 1979-05-24 |
| IT1055764B (en) | 1982-01-11 |
| BR7600062A (en) | 1976-08-31 |
| JPS51111818A (en) | 1976-10-02 |
| FR2298519B1 (en) | 1978-11-10 |
| SE7600715L (en) | 1976-07-28 |
| FR2298519A1 (en) | 1976-08-20 |
| DK159550B (en) | 1990-10-29 |
| DE2602256A1 (en) | 1976-07-29 |
| DK29776A (en) | 1976-07-28 |
| BE837894A (en) | 1976-07-26 |
| SE447373B (en) | 1986-11-10 |
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