WO2026068942A1 - Coated glass articles - Google Patents

Abstract

A coated glass article includes a glass substrate, a color suppression interlayer deposited over the glass substrate, and a fluorine doped tin oxide coating deposited over the color suppression interlayer. The fluorine doped tin oxide coating is comprised of two or more fluorine doped tin oxide layers, with the outermost fluorine doped tin oxide layer of the fluorine doped tin oxide coating having an electron concentration of from 4.0 x 10²⁰ to 6.0 x 10²¹ and a thickness of from 100 nm to 170 nm, while the fluorine doped tin oxide layer directly beneath the outermost fluorine doped tin oxide layer has an electron concentration of from 2.0 x 10¹⁸ to 5.5 x 10¹⁹ and a thickness of from 40 nm to 100 nm. The coated glass article has a sheet resistance of from 15 Ω/square to 40 Ω/square, transmits greater than or equal to 82% of the radiation having wavelengths of from 400 nm to 780 nm, and transmits greater than 78% of the radiation having wavelengths of from 900 nm to 1300 nm.

Description

1-29865

TITLE

COATED GLASS ARTICLES

BACKGROUND OF THE INVENTION

The invention relates to coated glass articles and, in particular, to coated glass articles for use as substrates for electronic devices.

Coatings on glass are commonly utilized to provide specific electrical and light transmittance properties. The attributes of the resulting coated glass substrate are dependent upon the specific coatings applied during the float glass process or an offline sputtering process. The coating compositions and thicknesses impart light transmittance properties within the coated article while also affecting the spectral properties. Desired attributes may be obtainable by adjusting the compositions or thicknesses of the coating layer or layers. However, adjustments to enhance a specific property can adversely impact other transmittance or spectral properties of the coated glass article. Obtaining desired spectral properties is often difficult when trying to combine specific light transmittance properties in a coated glass article.

It is known to provide a coated glass substrate for electronic devices that includes a color-suppression interlayer over the glass substrate with two layers of fluorine-doped tin oxide over the color-suppression interlayer. The two layers of fluorinedoped tin oxide are of about the same thickness, but the first fluorine-doped tin oxide layer is more heavily doped with fluorine than the second fluorine-doped tin oxide layer. It would be advantageous to provide a coated glass substrate for electronic devices with 1-29865 improved transmission of radiation in the near infrared while maintaining the desired sheet resistance.

SUMMARY OF THE INVENTION

According to an aspect of the invention, there is provided a coated glass article comprising a glass substrate, a color suppression interlayer deposited over the glass substrate, and a fluorine doped tin oxide coating deposited over the color suppression interlayer, wherein the fluorine doped tin oxide coating is comprised of two or more fluorine doped tin oxide layers. The outermost fluorine doped tin oxide layer of the fluorine doped tin oxide coating has an electron concentration of from 4.0 x 10²⁰ to 6.0 x 10²¹ and a thickness of from 100 nm to 170 nm, while the fluorine doped tin oxide layer directly beneath the outermost fluorine doped tin oxide layer has an electron concentration of from 2.0 x 10¹⁸ to 5.5 x 10¹⁹ and a thickness of from 40 nm to 100 nm. The coated glass article has a sheet resistance of from 15 Q/square to 40 Q/square, transmits greater than or equal to 82% of the radiation having wavelengths of from 400 nm to 780 nm, and transmits greater than 78% of the radiation having wavelengths of from 900 nm to 1300 nm.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as other advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description when considered in the light of the accompanying drawings in which: 1-29865

FIG. 1 is a schematic view, in cross-section, of a coated glass article in accordance with certain embodiments of the present invention; and

FIG. 2 is a schematic view, in vertical section, of an installation for practicing the float glass manufacturing process in accordance with an embodiment of the invention.

DESCRIPTION OF THE INVENTION

It is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific layers, articles, methods and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts. Hence, specific dimensions, directions, or other physical characteristics relating to the embodiments disclosed are not to be considered as limiting, unless expressly stated otherwise.

In the context of the present invention, where a layer is said to be “based on” a particular material or materials, this means that the layer predominantly consists of the corresponding said material or materials, which means that it comprises at least about 50 at.% of said material or materials.

When a layer is said to deposited or formed directly on another layer, it means that there are no intervening layers coatings therebetween.

A side of a glass substrate where a coating is formed may be referred to herein as the coated side. A second major surface of the glass substrate and an opposite side of the coated glass article may be uncoated. 1-29865

Unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

Throughout this specification, the term “comprising” or “comprises” means including the component(s) specified but not to the exclusion of the presence of other components. The term “consisting essentially of” or “consists essentially of’ means including the components specified but excluding other components except for materials present as impurities, unavoidable materials present as a result of processes used to provide the components, and components added for a purpose other than achieving the technical effect of the invention. Typically, when referring to compositions, a composition consisting essentially of a set of components will comprise less than 5% by weight, typically less than 3% by weight, more typically less than 1 % by weight of non-specified components.

The term “consisting of’ or “consists of’ means including the components specified but excluding other components.

Whenever appropriate, depending upon the context, the use of the term “comprises” or “comprising” may also be taken to include the meaning “consists essentially of’ or “consisting essentially of”, and also may also be taken to include the meaning “consists of’ or “consisting of”. 1-29865

References herein such as “in the range x to y” are meant to include the interpretation “from x to y” and so include the values x and y.

Certain ranges are presented herein with numerical values being preceded by the term “about.” The term “about” is used herein to provide literal support for the exact number that it precedes, as well as a number that is near to or approximately the number that the term precedes. In determining whether a number is near to or approximately a specifically recited number, the near or approximating unrecited number may be a number which, in the context in which it is presented, provides the substantial equivalent of the specifically recited number.

Further, any feature set out above in relation to the first aspect of the present invention may also be utilised in relation to any other aspects of the present invention, and any invention described herein may be combined with any feature of any other invention described herein mutatis mutandis. It will also be appreciated that optional features applicable to one aspect of the invention can be used in any combination, and in any number. Moreover, they can also be used with any of the other aspects of the invention in any combination and in any number. This includes, but is not limited to, the dependent claims from any claim being used as dependent claims for any other claim in the claims of this application.

A coated glass article according to certain embodiments of the invention comprises a glass substrate, a color suppression interlayer deposited over the glass substrate, and a fluorine doped tin oxide coating deposited over the color suppression interlayer, the fluorine doped tin oxide coating being comprised of two or more fluorine 1-29865 doped tin oxide layers. An optional buffer may be deposited over the outermost fluorine doped tin oxide coating.

Fig. 1 schematically illustrates a cross-section of a coated glass article 1 according to certain preferred embodiments of the invention. In such embodiments, the coated glass article 1 comprises a transparent glass substrate 2 that has been sequentially coated with a color suppression interlayer comprising a layer based on tin dioxide 3 and a layer based on silicon dioxide 4. A fluorine doped tin oxide coating is deposited over the color suppression interlayer, the fluorine doped tin oxide coating comprising a first layer based on fluorine doped tin oxide 5 (the first fluorine doped tin oxide layer) and a second layer based on fluorine doped tin oxide 6 (the second fluorine doped tin oxide layer). An optional buffer layer 7 may be deposited over the second fluorine doped tin oxide layer 6 to provide an optimized interface to an electronic device. The optional buffer layer 7 may be the outermost layer of the coated glass article 1.

In certain embodiments, the coated glass article consists of the glass substrate, the color suppression interlayer, and the fluorine doped tin oxide coating. In some of these embodiments, the coated glass article consists of the glass substrate, the first color suppression layer, the second color suppression layer, the first fluorine doped tin oxide coating, and the second fluorine doped tin oxide layer.

In certain other embodiments, the coated glass article consists of the glass substrate, the color suppression interlayer, the fluorine doped tin oxide coating, and the buffer layer. In some of these embodiments, the coated glass article consists of the glass substrate, the first color suppression layer, the second color suppression layer, the 1-29865 first fluorine doped tin oxide coating, the second fluorine doped tin oxide layer, and the buffer layer.

The glass substrate 2 may be of a conventional glass composition known in the art. Preferably, the glass substrate 2 is a soda-lime-silica glass. However, the glass substrate 2 may be of another composition such as, for example, a borosilicate or an aluminosilicate composition. Additionally, the glass substrate thickness may vary between embodiments. It is preferred that the glass substrate 2 is clear and transparent to light.

The color suppression interlayer is deposited over and preferably directly on the glass substrate 2 reduces a reflected color or iridescence of the coated glass article 1 . In certain embodiments, the color suppression interlayer is of a two-layer system such as that illustrated in Fig. 1 . In other embodiments (not depicted), the color suppression interlayer may be provided as a single coating layer. Suitable color suppression interlayers are described in U.S. Pat. Nos. 4308316, 4612217, and 4419386, the disclosures of which are hereby incorporated by reference in their entirety.

In the embodiment where the color suppression interlayer is the two-layer system illustrated in Fig. 1 , the coated glass article comprises a first color suppression layer 3 that is deposited over and preferably directly on the glass substrate 2 and a second color suppression layer 4 deposited over and preferably directly on the first color suppression layer 3.

In some embodiments, the first color suppression layer 3 is formed of an inorganic metal oxide or inorganic metalloid oxide, preferably an inorganic metal oxide. Preferably, in these embodiments, the first color suppression layer 3 comprises 1-29865 undoped tin oxide (SnC>2) deposited at a thickness of about 10 nm to about 40 nm. Preferably, the thickness of the first color suppression layer 3 is about 15 nm to about 35 nm. More preferably, the thickness of the first color suppression layer 3 is about 20 nm to about 30 nm, and most preferably is about 25 nm.

The second color suppression layer 4 may be formed of an inorganic metal oxide or inorganic metalloid oxide, preferably an inorganic metalloid oxide. Preferably, in these embodiments, the second color suppression layer 4 comprises silicon dioxide (SiC>2) deposited at a thickness of about 10 nm to about 40 nm. In certain preferred embodiments, the thickness of the second color suppression layer 4 is about 15 nm to about 35 nm. More preferably, the thickness of the second color suppression layer 4 is about 20 nm to about 30 nm, and is most preferably about 25 nm.

A fluorine doped tin oxide coating is deposited over and preferably directly on the color suppression interlayer, the fluorine doped tin oxide coating comprising at least a first fluorine doped tin oxide layer 5 and a second fluorine doped tin oxide layer 6 deposited directly on the first fluorine doped tin oxide layer 5. The second fluorine doped tin oxide layer 6 is doped so as to have an electron concentration of from 4.0 x 1O²⁰ to 6.0 x 10²¹ , and the fluorine doped tin oxide layer directly beneath the outermost fluorine doped tin oxide layer (the first fluorine doped tin oxide layer 5) has an electron concentration of from 2.0 x 10¹⁸ to 5.5 x 10¹⁹. Thus, the second layer 6 is doped to a level such that it has an electron concentration that is much greater than the electron concentration of the first layer 5.

In embodiments where the fluorine doped tin oxide coating includes one or more layers based on fluorine doped tin oxide in addition to the first and second fluorine 1-29865 doped tin oxide layers 5 and 6, the one or more additional fluorine doped tin oxide layers are deposited between the color suppression interlayer and the first fluorine doped tin oxide layer.

The fluorine doped tin oxide coating preferably has a thickness of from 200 nm to 300 nm, and more preferably of from 240 nm to 280 nm. The second fluorine doped tin oxide layer 6 has a thickness of from 100 nm to 170 nm, and the fluorine doped tin oxide layer directly beneath the outermost fluorine doped tin oxide layer has a thickness of from 40 nm to 100 nm.

As noted above, in some embodiments an optional buffer layer 7 is deposited over the second fluorine doped tin oxide layer 6 to provide an optimized interface to an electronic device. The optional buffer layer may be a dielectric layer, preferably one or more of an oxide of tin, an oxide of titanium, an oxide of nickel, and an oxide of silicon. In some preferred embodiments, a buffer layer based on undoped tin oxide is provided over the fluorine-doped tin oxide coating.

In certain preferred embodiments, the optional buffer is the outermost layer of the coated glass article 1 . In other embodiments, where a buffer layer is not provided, the second fluorine-doped tin oxide layer is preferably the outermost layer of the coated glass article 1.

The combined thickness of the fluorine doped tin oxide coating and the buffer layer, if one is provided, is preferably from 200 nm to 400 nm, and is more preferably from 250 nm to 350 nm.

The coated glass article has a sheet resistance of from 15 Q/square to 36 Q/square, preferably of from 15 Q/square to 22 Q/square. Further, the coated glass 1-29865 article transmits more than 78.0% of the near infrared radiation (TNIR), that is, radiation having wavelengths from 900 to 1300 nm, and in certain preferred embodiments has a TNIR greater than 80%. In addition, the coated glass article transmits more than 82.0% of the visible light (Tvis), that is, radiation having wavelengths from 400 to 780 nm, and in certain preferred embodiments has a Tvis of greater than 83.0%. The coated glass article preferably has a Tsoi of from 75% to 80%.

The various layers of the coated glass article may be deposited by any suitable method, preferably online during the float glass manufacturing process, and most preferably by atmospheric chemical vapor deposition during such process. Thus, in certain embodiments, each of the layers deposited over the glass substrate is pyrolytic, which term, as used herein, refers to a coating or a layer that is chemically bonded to a glass substrate. In preferred embodiments, the layers are formed by chemical vapor deposition (CVD) processes.

In some preferred embodiments, the coating layers may be applied to the glass substrate 2 in conjunction with its manufacture. In an embodiment, the glass substrate 2 may be formed utilizing the well-known float glass manufacturing process. The float glass manufacturing process is typically carried out utilizing a float glass installation such as the installation 30 depicted in the Fig. 2. However, it should be understood that the float glass installation 30 described herein is only illustrative of such installations. In these embodiments, the glass substrate 2 may also be referred to as a glass ribbon 38. However, it should be appreciated that the method can be utilized apart from the float glass manufacturing process or well after formation and cutting of the glass ribbon. 1-29865

As illustrated in Fig. 2, the float glass installation 30 may comprise a canal section 32 along which molten glass 34 may be delivered from a melting furnace to a float bath section 36 where the glass substrate may be formed. In this embodiment, the glass substrate will be referred to as a glass ribbon 38. The glass ribbon 38 may be a preferable substrate on which the multi-layer coating 14 may be formed. However, it should be appreciated that the glass substrate may not be limited to being a glass ribbon.

The glass ribbon 38 advances from the bath section 36 through an adjacent annealing lehr 40 and a cooling section 42. The float bath section 36 includes: a bottom section 44 within which a bath of molten tin 46 may be contained, a roof 48, opposite side walls (not depicted) and end walls 50, 52. The roof 48, side walls and end walls 50, 52 together define an enclosure 54 in which a non-oxidizing atmosphere may be maintained to prevent oxidation of the molten tin 46.

In operation, the molten glass 34 flows along the canal 32 beneath a regulating tweel 56 and downwardly onto the surface of the tin bath 46 in controlled amounts. On the molten tin surface, the molten glass 34 spreads laterally under the influence of gravity and surface tension, as well as certain mechanical influences, and it may be advanced across the tin bath 46 to form the glass ribbon 38. The glass ribbon 38 may be removed from the bath section 36 over lift out rolls 58 and may be thereafter conveyed through the annealing lehr 40 and the cooling section 42 on aligned rolls. The deposition of the coating layers preferably takes place in the float bath section 36, although it may be possible for deposition to take place further along the glass production line, for example, in the gap 60 between the float bath 36 and the annealing lehr 40, or in the annealing lehr 40.

As illustrated in Fig. 2, a coating apparatus or coater 62 may be shown within the float bath section 36. The various coating layers of the coated glass article of the invention may be formed utilizing various ones of the coaters 62, 64, 66, 68 and, if needed, additional coaters (not shown).

A suitable non-oxidizing atmosphere, generally nitrogen or a mixture of nitrogen and hydrogen in which nitrogen predominates, may be maintained in the float bath section 36 to prevent oxidation of the molten tin 46 comprising the float bath. The atmosphere gas may be admitted through conduits 70 operably coupled to a distribution manifold 72. The non-oxidizing gas may be introduced at a rate sufficient to compensate for normal losses and maintain a slight positive pressure, on the order of between about 0.001 and about 0.01 atmosphere above ambient atmospheric pressure, so as to prevent infiltration of outside atmosphere. For purposes of the describing the presently disclosed subject matter, the above-noted pressure range may be considered to constitute normal atmospheric pressure. Preferably, the coating layers may be formed at essentially atmospheric pressure. Thus, the pressure of the float bath section 36, annealing lehr 40, and/or in the gap 60 between the float bath section 36 and the annealing lehr 40 may be essentially atmospheric pressure.

Heat for maintaining the desired temperature regime in the float bath section 36 and the enclosure 54 may be provided by radiant heaters 74 within the enclosure 54. The atmosphere within the lehr 40 may be typically atmospheric air, as the cooling section 42 may not enclosed and the glass ribbon 38 may be therefore open to the ambient atmosphere. The glass ribbon 38 may be subsequently allowed to cool to ambient temperature. To cool the glass ribbon 38, ambient air may be directed against the glass ribbon 38 as by fans 76 in the cooling section 42. Heaters (not depicted) may also be provided within the annealing lehr 40 for causing the temperature of the glass ribbon 38 to be gradually reduced in accordance with a predetermined regime as it may be conveyed therethrough.

The various layers of the coated glass article may be formed using well known chemistries for the chemical vapor deposition of such coating layers. For example, the layer based on silicon dioxide can be formed by processes described in US Patent Nos. 5798142, 6106892, or 9404179, each of which is incorporated herein by reference. The layers based on fluorine doped tin oxide can be formed, for example, by the methods described in US Patent No. 5698262, which is incorporated herein by reference. As is well understood, layers of undoped tin oxide can be formed by similar methods where the fluorine precursor is omitted.

EXAMPLES

The invention is illustrated but not limited by the following Examples. In the Examples, as in the remainder of the description and claims, T_soi represents the direct solar energy transmittance integrated over the wavelength range 300 to 2500 nm according to the relative solar spectral distribution for air mass 1 .5, TNIR represents the near-infrared radiation (900 nm to 1300 nm) transmitted through the coated glass article, Tvis represents the visible light (400 nm to 780 nm) transmitted through the coated glass article, Rs represents the sheet resistance in ohms/square, and Ne 1-29865 represents the electron concentration of a layer at 300 °K in 1/cm³, the Ne corresponding to the fluorine dopant level in the various fluorine doped tin oxide layers.

The Table provides the Rs, TNIR, T_SOI, TVIS, and the thicknesses (in nm) and Ne for each of the first and second fluorine doped tin oxide layers for Comparative Example C1 and Examples 2-11 , with the layer thicknesses shown in nanometers. Comparative Example C1 and Examples 2-11 are modelled by computer using software calibrated on the basis of laboratory and production coated glass articles, and the properties exhibited by each are predictive. Each example and comparative example is modelled on a 2.5 mm thick clear glass substrate with a color suppression interlayer thereon of a first layer of 23 nm of undoped tin oxide and a second layer of 29 nm of silicon dioxide, with the fluorine doped tin oxide layers directly on the silicon dioxide layer. Comparative Example C1 corresponds to a known coated glass article.

TABLE 1-29865

In accordance with the provisions of the patent statutes, the invention has been described in what is considered to represent its preferred embodiments. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.

Claims

1-29865 WHAT IS CLAIMED IS:

1 . A coated glass article comprising: a glass substrate; a color suppression interlayer deposited over the glass substrate; and a fluorine doped tin oxide coating deposited over the color suppression interlayer, wherein the fluorine doped tin oxide coating is comprised of two or more fluorine doped tin oxide layers; wherein the outermost fluorine doped tin oxide layer of the fluorine doped tin oxide coating has an electron concentration of from 4.0 x 10²⁰ to 6.0 x 10²¹ and a thickness of from 100 nm to 170 nm, and the fluorine doped tin oxide layer directly beneath the outermost fluorine doped tin oxide layer has an electron concentration of from 2.0 x 10¹⁸ to 5.5 x 10¹⁹ and a thickness of from 40 nm to 100 nm; and wherein the coated glass article has a sheet resistance of from 15 Q/square to 40 Q/square, transmits greater than or equal to 82% of the radiation having wavelengths of from 400 nm to 780 nm, and transmits greater than 78% of the radiation having wavelengths of from 900 nm to 1300 nm.

2. The coated glass article of claim 1 , wherein the sheet resistance is from 15 Q/square to 22 Q/square.

3. The coated glass article of any preceding claim, wherein the sheet resistance is about 18.5 Q/square. 1-29865

4. The coated glass article of any preceding claim, wherein the fluorine doped tin oxide coating has a thickness of from 200 nm to 280 nm.

5. The coated glass article of any preceding claim, further comprising a buffer layer deposited over the outermost fluorine doped tin oxide layer.

6. The coated glass article of claim 5, wherein the buffer layer is based on an oxide of titanium, silicon, tin, or nickel.

7. The coated glass article of claim 5 or claim 6, wherein the buffer layer is based on undoped tin oxide.

8. The coated glass article of claim 7, wherein the combined thickness of the fluorine doped tin oxide coating and the buffer layer is from 200 nm to 400 nm.

9. The coated glass article of claim 7, wherein the combined thickness of the fluorine doped tin oxide coating and the buffer layer is from 250 nm to 350 nm.

10. The coated glass article of any preceding claim, wherein the color suppression interlayer comprises one chosen from the group consisting of: a single metal oxide layer, a metal oxide layer and a silica layer, and a gradient layer. 1-29865

11 . The coated glass article of any preceding claim, wherein the coated glass article has Tsoi of from 75% to 80%.

12. The coated glass article of any preceding claim, wherein the coated glass article transmits greater than 83% of the radiation having wavelengths of from 400 nm to 780 nm.

13. The coated glass article of any preceding claim, wherein the coated glass article transmits greater than 80% of the radiation having wavelengths of from 900 nm to 1300 nm.

14. The coated glass article of any preceding claim, wherein the color suppression interlayer comprises a tin oxide layer having a thickness of about 10 nm to about 40 nm deposited over the glass substrate and a silica layer having a thickness of about 10 nm to about 40 nm deposited over the tin oxide layer.

15. The coated glass article of any preceding claim, wherein the color suppression interlayer comprises a tin oxide layer having a thickness of about 15 nm to about 35 nm deposited over the glass substrate and a silica layer having a thickness of about 15 nm to about 35 nm deposited over the tin oxide layer.

16. The coated glass article of any preceding claim, wherein the color suppression interlayer comprises a tin oxide layer having a thickness of about 20 nm to 1-29865 about 30 nm deposited over the glass substrate and a silica layer having a thickness of about 20 nm to about 30 nm deposited over the tin oxide layer.

17. The coated glass article of any preceding claim, wherein the color suppression interlayer comprises a tin oxide layer having a thickness of about 25 nm deposited over the glass substrate and a silica layer having a thickness of about 25 nm deposited over the tin oxide layer.