RU2481364C2 - Intermediate layers providing improved top layer functionality - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to production of articles with a multilayer light-sensitive coating and can be used to make thin-film solar cells and photocatalytic articles. The article has a substrate, e.g. a glass substrate, and a first coating formed on at least part of the substrate. The first coating is multilayered and contains a mixture of oxides including oxides of at least two elements selected from P, Si, Ti, Al and Zr. A functional coating is formed on at least part of the first coating. The functional coating is selected from an electroconductive coating and a light-sensitive coating. In one embodiment of the invention, the functional coating contains tin oxide doped with fluorine. In another embodiment, the functional coating contains titanium dioxide. A glass substrate, for example, is made in order to make a coated article. The first multilayer coating is formed on at least part of the substrate by chemical vapour deposition. The functional coating is formed on at least part of the first coating.

EFFECT: high functionality of the first layer of the article.

14 cl, 5 dwg, 12 tbl, 6 ex

Description

Cross reference to related applications

This application claims priority under US 12 / 273,617; 12 / 273,623 and 12 / 273,641, all filed November 19, 2008, and all three of which are fully incorporated by reference.

FIELD OF THE INVENTION

This invention relates generally to coated products and, in particular, to products with a multilayer coating having a functional top layer and at least one intermediate layer.

State of the art

Products with multilayer coatings are widely used in various applications. One example is in the field of thin-film solar cells. A typical solar cell includes a substrate, such as a glass plate, with a transparent conductive film (first electrode). A semiconductor film with a photoelectric converter material is applied to a transparent conductive film. The element includes another substrate with a transparent conductive film (second electrode). An electrolyte can be placed between the two electrodes. When the photoelectric converter material adsorbed on the semiconductor film is illuminated, the electrons generated by the illumination move through the semiconductor film into one of the transparent conductive films. For example, electrons can move through the first electrode, through the electrical lead, and onto another electrode. In solar cells, for photoelectric conversion efficiency it is important that the electrons move as fast as possible through the first conductive film to another electrode. Thus, it is desirable that the surface resistivity of the transparent conductive film is low. If the electrons do not move quickly, recombination of the electrons with the material of the photovoltaic converter (commonly called "reverse voltage current" or "reverse current") can occur. It is also desirable that the conductive film be very transparent to allow the maximum amount of solar radiation to pass to the material of the photovoltaic converter. Therefore, it would be desirable to create a product with a coating for a solar cell that increases the flow of electrons through a transparent conductive film. That is, a transparent conductive film with a low surface resistivity.

Another example of the use of coated products is the field of photocatalytic products. It is known to deposit a photocatalytic coating, such as titanium dioxide, on a substrate to create a coated article with self-cleaning properties. Under the influence of certain electromagnetic radiation, such as ultraviolet radiation, the photocatalytic coating interacts with organic pollutants on the surface of the coating, decomposing or destroying organic pollutants. However, conventional photocatalytic products have a relatively high reflectance of visible light and, therefore, may not be suitable for use in some architectural applications. In addition, conventional photocatalytic coatings can be susceptible to degradation by the traditionally called “sodium ion poisoning” caused by the diffusion of sodium ions from the underlying glass substrate into the photocatalytic coating. In addition, conventional photocatalytic coatings tend to exhibit rainbow effects that reduce the aesthetic appearance of coated products.

Therefore, it would be desirable to create a coated article with an intermediate layer between the substrate and a functional top layer (such as, but not limited to a conductive photovoltaic transparent coating or photocatalytic coating), which acts not only as a barrier to the diffusion of sodium ions, but also improves the performance coated products. For example, performance can be improved by reducing the reflectance of the coated article and / or by suppressing the color of the article and / or by increasing the functionality of the top layer. For example, in photovoltaic applications, the intermediate layer can reduce the specific surface resistance of the upper layer (for example, a transparent conductive layer) to increase the flow of electrons. In photocatalytic applications, the intermediate layer can increase the photocatalytic activity of the photocatalytic coating.

Disclosure of invention

The coated article includes a substrate and a first coating formed on at least a portion of the substrate. The first coating includes oxides of at least two elements of P, Si, Ti, Al and Zr. A functional coating is formed on at least a portion of the first coating. In one non-limiting embodiment, the first coating comprises at least Ti and Si oxides. In another non-limiting embodiment, the first coating comprises at least oxides of Ti, Si, and P. In yet another non-limiting embodiment, the first coating includes at least oxides of Ti, Si, and Al. Other embodiments may include any combination of two or more of these materials. Examples of functional coatings include, but are not limited to, photosensitive coatings (such as photocatalytic coatings and / or photohydrophilic coatings) and electrically conductive coatings. The functional coating may be applied to the first coating with any combination of the above components.

Another coated article includes a glass substrate and a first coating formed on at least a portion of the substrate. The first coating includes oxides of at least two elements of P, Si, Ti, Al and Zr. A functional coating is formed at least on a portion of the first coating. The functional coating is selected from titanium dioxide and tin oxide doped with fluorine.

A method of manufacturing a coated product includes obtaining a glass substrate; forming a first coating on at least a portion of the CVD glass substrate (chemical vapor deposition) by directing the first coating composition onto the glass substrate, the first coating composition comprises a silicon dioxide precursor, a titanium dioxide precursor and a silicon dioxide catalyst containing at least one catalyst material with at least one element of P, Al and Zr; and forming a functional coating on at least a portion of the first CVD coating by directing the second coating composition onto a glass substrate, the second coating composition includes a fluorine doped tin oxide precursor composition or a titanium dioxide composition precursor.

Another coated article includes a substrate and a first coating formed on at least a portion of the substrate. The first coating comprises a mixture of oxides containing oxides of at least two elements of P, Si, Ti, Al and Zr. A conductive coating is formed at least on a portion of the first coating. The conductive coating includes one or more oxides of Zn, Fe, Mn, Al, Ce, Sn, Sb, Hf, Zr, Ni, Zn, Bi, Ti, Co, Cr, Si or In, or alloys of two or more of these materials .

A method of reducing the surface resistivity of a conductive coating includes obtaining a substrate; forming a first coating on at least a portion of the substrate, the first coating comprising oxides of at least two elements of P, Si, Ti, Al and Zr; and forming a conductive coating on at least a portion of the first coating.

A method of increasing dullness and / or increasing the transmittance of visible light of a coated article includes obtaining a substrate; forming a first coating on at least a portion of the substrate, the first coating comprising oxides of at least two elements of P, Si, Ti, Al and Zr; and the formation of a functional coating, at least in part of the first coating.

Another coated article includes a substrate and a first coating formed on at least a portion of the substrate. The first coating comprises a mixture of oxides comprising oxides of at least two elements of P, Si, Ti, Al and Zr. The photosensitive coating is formed at least in part of the first coating.

The photosensitive article includes a glass substrate and a first coating formed on at least a portion of the substrate. The first coating comprises a mixture of silica, titanium dioxide and alumina. A photosensitive functional coating comprising titanium dioxide is formed on at least a portion of the first coating.

A method of increasing the photocatalytic activity of a photosensitive coating includes preparing a substrate; forming a first coating on at least a portion of the substrate, the first coating comprising oxides of at least two elements of P, Si, Ti, Al and Zr; and forming a photosensitive coating on at least a portion of the first coating.

A method of manufacturing a photosensitive product includes obtaining a glass substrate; forming a first coating on at least a portion of the CVD glass substrate by directing the first coating composition onto the glass substrate, the first coating composition comprising tetraethylorthosilicate, titanium isopropoxide and dimethylaluminium isopropoxide; and forming a photosensitive coating on at least a portion of the first CVD coating by directing the second coating composition onto a glass substrate, the photosensitive coating comprising titanium dioxide.

Brief Description of the Drawings

A full understanding of the invention will be achieved from the following description when considered in conjunction with the accompanying figures.

Figure 1 is a side projection (not to scale) of a coated article incorporating features of the invention;

Figure 2 is a graph of the specific surface resistance versus [Sn] in fluorine doped tin oxide coatings formed directly on glass or on an intermediate layer of the invention;

Figure 3 is a graph of the percentage of transmission on wavelength for coatings of tin oxide doped with fluorine formed directly on glass or on an intermediate layer of the invention;

Figure 4 is a graph of reflection versus titanium dioxide coating thickness for coated articles of Example 5; and

Figure 5 is a graph of the color change of the coated products of example 6.

The implementation of the invention

As used in the description, spatial or directional terms, such as “left,” “right,” “inside,” “outside,” “above,” “below,” and the like, are used in the invention as as they are presented in the figures. However, it should be understood that the invention may allow various alternative orientations and, accordingly, such terms cannot be construed as limiting. In addition, in accordance with the use in the description, all numbers representing dimensions, physical characteristics, technological parameters, amounts of components, reaction conditions, etc. used in the description and claims should be presented in all cases, as preceded by the term "about". Accordingly, unless otherwise specified, the numerical values set forth in the subsequent application and claims may vary depending on the desired properties, which are expected to be obtained in accordance with the present invention. At the very least, and not as an attempt to limit the application of the theory of equivalents to the scope of the claims of the claims, each numerical value should be considered, at least taking into account the significant figures presented and using conventional rounding methods. In addition, it should be understood that all ranges disclosed in the description include the start and end values of the range and all subranges included therein. For example, the indicated range of “1-10” should be considered as including all subranges between (and inclusive) a minimum value of 1 and a maximum value of 10; that is, all subranges starting with a minimum value of 1 or more and ending with a maximum value of 10 or less, for example, 1-3.3, 4.7-7.5, 5.5-10, etc. Furthermore, as used in the description, the terms “formed on”, “deposited on” or “obtained on” mean formed, deposited on or obtained on, but not necessarily in direct contact with the surface. For example, a coating layer “formed on” a substrate does not exclude the presence of one or more other coating layers or films of the same or different composition located between the formed coating layer and the substrate. As used herein, “polymer” or “polymer” includes oligomers, homopolymers, copolymers and terpolymers, for example, polymers formed from two or more types of monomers or polymers. The terms "visible region" or "visible light" refer to electromagnetic radiation with a wavelength of 380-760 nm. The terms "infrared region" or "infrared cure" refer to electromagnetic radiation with a wavelength in the range from more than 760 nm to 100,000 nm. The terms "ultraviolet region" or "ultraviolet radiation" mean electromagnetic energy with a wavelength in the range from 300 nm to less than 380 nm. The terms "microwave region" or "microwave radiation" refer to electromagnetic radiation with a frequency in the range from 300 MHz to 300 GHz. In addition, all documents, such as, but not limited to, issued patents and patent applications referred to in the application should be considered as fully “incorporated by reference”. In a subsequent discussion, refractive index values are values for a reference wavelength of 550 nanometers (nm). The term "film" refers to the field of coatings of the desired or selected composition. A “layer” includes one or more “films”. A “coating” or “coating package” consists of one or more “layers”.

The coated product 10, with the features of the invention, is shown in FIG. Product 10 includes a substrate 12 with at least one main surface. The first coating (intermediate layer) 14 of the invention is formed on at least a portion of the main surface. A second coating (functional coating) 16 is formed on at least a portion of the first coating 14. While certain typical embodiments will now be described, it should be understood that one or more features of the invention included in these embodiments can be combined with one or a large number of features of other implementations and that the invention is not limited to certain typical implementations described below.

In a General plan of implementation of the invention, the substrate 12 may include any desired material with any desired characteristics. For example, the substrate 12 may be transparent, translucent, or opaque in visible light. "Transparent" means having a visible light transmission of more than 0% to 100%. Alternatively, the substrate 12 may be translucent or opaque. “Translucent” means that allows the transmission of electromagnetic energy (for example, visible light), but scatters this energy in such a way that objects from the observer’s side are not clearly visible. “Opaque” means having a transmittance of visible light of 0%. Examples of suitable materials include, but are not limited to, plastic substrates (e.g., acrylic polymers such as polyacrylates; polyalkyl methacrylates such as polymethyl methacrylates, polymethacrylates, polypropyl methacrylates and the like; polyurethanes; polycarbonates; polyalkyl terephthalates such as polyethylene terephthalate (PET), polypropyl polybutylene terephthalates and the like; polysiloxane-containing polymers; or copolymers of any monomers to produce them, or any mixtures thereof); metal substrates, such as but not limited to galvanized steel, stainless steel and aluminum; ceramic substrates; tile substrates;

glass substrates; or mixtures or combinations of any of the above. For example, the substrate may include ordinary soda lime silicate glass, borosilicate glass, or lead glass. Glass may be colorless glass. "Colorless glass" means untouched or unpainted glass. Alternatively, the glass may be tinted or otherwise colored glass. The glass may be annealed or heat-treated glass. As used herein, the term “heat treated” means hardened or at least partially hardened. The glass can be of any type, for example, ordinary float glass and can be of any composition, with any optical properties, for example, with any amount of transmittance in the visible, ultraviolet, infrared regions and / or total transmission of solar energy. "Float glass" means glass made by a conventional float process in which molten glass is supplied to molten metal in a bath and cooled under controlled conditions to form a strip of float glass. Non-limiting examples of glass suitable for a substrate are described in US 4,746,347; 4,792,536; 5,030,593; 5,030,594; 5,240,886; 5,385,872; and 5,393,593. Non-limiting examples of glass that may be used in the practice of the invention include Solargreen®, Solextra®, GL-20®, GL-35 ™, Solarbronze®, Starphire®, Solarphire®, Solarphire PV® and Solargray® glasses, all commercially available PPG Industries Inc. of Pittsburgh, Pennsylvania. The glass may have a smooth surface or, alternatively, may have a rough or textured surface. In one non-limiting embodiment, the glass surface may have a surface roughness (RMS) in the range of 100 nm to 5 mm.

The substrate 12 may have any desired dimensions, for example, length, width, shape or thickness. For example, the substrate 12 may be flat, curved, or have both flat and curved parts. In one non-limiting embodiment, the thickness of the substrate 12 may be 1-10 mm, for example 1-5 mm, for example 2-4 mm, for example 3-4 mm.

In one non-limiting embodiment, the substrate 12 may have a high transmittance of visible light at a reference wavelength of 550 nanometers (nm). "High transmittance of visible light" means the transmission of visible light at 550 nm, greater than or equal to 85%, for example, greater than or equal to 87%, for example, greater than or equal to 90%, for example, greater than or equal to 91%, for example, greater than or equal to 92 %

The first coating (intermediate layer) 14 provides the coated product 10 with various operational advantages, as will be described in detail below. In one non-limiting embodiment of the invention, the first coating 14 may be a homogeneous coating. “Homogeneous coating” means a coating in which materials are randomly distributed over the coating. Alternatively, the first coating 14 may include a large number of coating layers or films (for example, two or more separate coating films). Alternatively, the first coating 14 may be a gradient layer. “Gradient layer” means a layer with two or more components with a continuously (or stepwise) varying concentration of the components as the distance from the substrate changes.

In one non-limiting embodiment, the first coating 14 comprises a mixture of two or more oxides selected from oxides of silicon, titanium, aluminum, zirconium and / or phosphorus. Oxides may be present in any desired proportions. In one non-limiting embodiment, the first coating 14 comprises a mixture of silicon dioxide and titanium dioxide, with a silica content in the range of 0.1-99.9% by weight. and the content of titanium dioxide in the range of 99.9-0.1% of the mass. The first coating 14 may be a homogeneous coating. Alternatively, the first coating 14 may be a gradient coating with varying proportions of silicon dioxide and titanium dioxide in the coating. For example, the first coating 14 can be mainly silicon dioxide in the region adjacent to the surface of the substrate, and mainly titanium dioxide in the outer part of the first coating 14.

As discussed above, the first coating 14 may include mixtures of at least two oxides of elements selected from silicon, titanium, aluminum, zirconium and / or phosphorus. Such mixtures include, but are not limited to, titanium dioxide and phosphorus oxide; silica and alumina; titanium dioxide and alumina; silica and phosphorus oxide; titanium dioxide and phosphorus oxide; silica and zirconia; titanium dioxide and zirconia; alumina and zirconia; alumina and phosphorus oxide; zirconia and phosphorus oxide; or any combination of the above materials. The relative proportions of the oxides can be any desired amount, for example, 0.1-99.9% of the mass. one material and 99.9-0.1% of the mass. other material.

In addition, the first coating 14 may include mixtures of at least three oxides, such as but not limited to three or more oxides of elements selected from silicon, titanium, aluminum, zirconium and / or phosphorus. Examples include, but are not limited to, mixtures containing silica, titanium dioxide and phosphorus oxide; silica, titanium dioxide and alumina; and silicon dioxide, titanium dioxide and zirconia. In one non-limiting embodiment, the first coating 14 comprises a mixture of silicon dioxide and titanium dioxide with at least one other oxide selected from alumina, zirconia and phosphorus oxide. Relative proportions of oxides may be present in any desired amount, such as 0.1-99.9% of the mass. one material, 99.9-0.1% of the mass. the second material and 0.1-99.9% of the mass. third material.

One particular first coating 14 of the invention includes a mixture of silica, titanium dioxide and phosphorus oxide. Silicon dioxide may be present in the range of 30-80% vol. Titanium dioxide may be present in the range of 5-69% vol. Phosphorus oxide may be present in the range of 1-15% vol.

The first coating 14 may be of any desired thickness, such as, but not limited to 10-120 nm, for example, 30-80 nm, for example, 40-80 nm, for example, 30-70 nm.

The second coating (top layer) 16 includes a functional coating. Examples of functional coatings suitable for the invention include, but are not limited to conductive coatings, sunscreens, low emissivity coatings, and photosensitive coatings.

In one non-limiting embodiment, the second coating 16 includes at least one electrically conductive oxide layer, such as a doped oxide layer. For example, the second coating 16 may include one or more oxide materials, such as but not limited to one or more oxides of one or more elements of Zn, Fe, Mn, Al, Ce, Sn, Sb, Hf, Zr, Ni , Zn, Bi, Ti, Co, Cr, Si or In, or an alloy of two or more of these materials, such as zinc stannate. The second coating 16 may also include one or more alloying materials, such as, but not limited to F, In, Al and / or Sb. In one non-limiting embodiment, the second coating 16 is a fluorine doped tin oxide coating with a fluorine content of less than 20% by weight of the coating precursor material. in relation to the total weight of the materials of the precursor, for example, less than 15 wt.%, for example, less than 13 wt.%, for example, less than 10 wt. The second coating 16 may be amorphous, crystalline, or at least partially crystalline.

In one non-limiting embodiment, the second coating 16 includes fluorine doped tin oxide with a thickness of more than 200 nm, for example, more than 250 nm, for example, more than 350 nm, for example, more than 380 nm, for example, more than 400 nm, for example, more than 420 nm. In one non-limiting embodiment, the thickness is in the range of 350-420 nm.

The intermediate layer 14 of the invention provides a topcoat 16 (e.g., tin oxide doped with fluorine) with a specific surface resistance of less than 15 Ohms per square (Ω / □), for example, less than 14 Ω / □, for example, less than 13.5 Ω / □, for example, less than 13 Ω / □, for example, less than 12 Ω / □, for example, less than 11 Ω / □, for example, less than 10 Ω / □.

In another non-limiting embodiment, the second coating 16 may be a photosensitive coating. The terms “photosensitive” or “photoactive” refer to the photo-generation of an electron-hole pair when illuminated by radiation of a certain frequency, such as ultraviolet (“UV”) light. The photosensitive coating may be photocatalytic, photoactive hydrophilic, or both. "Photocatalytic" means a coating with self-cleaning properties, that is, a coating that, when exposed to a certain electromagnetic radiation, such as UV, interacts with organic pollutants on the surface of the coating to destroy or decompose organic pollutants. Photoactive “hydrophilic” means a coating for which the wetting angle of a drop of water on the coating decreases over time as a result of exposure to electromagnetic radiation in the photoabsorption band of the material. For example, the contact angle can decrease to less than 15 °, for example, less than 10 °, and can become superhydrophilic, for example, decrease to less than 5 °, after sixty minutes of exposure to radiation in the photoabsorption band of the material, with an intensity of 24 W / m ² on the surface coverings. Although the photosensitive coating may not necessarily be photocatalytic to such an extent that it will be self-cleaning, that is, it may not be photocatalytic enough to decompose organic material like dirt on the surface of the coating within an acceptable or economically acceptable period of time. For example, photocatalytic activity may be less than 4 × 10 ^-3 per centimeter per minute (cm ^-1 min ^-1 ), for example, less than 3 × 10 ^-3 cm ^-1 min ^-1 , for example, less than 2 × 10 ^-3 cm ^{- 1} min ^-1 , for example, less than 1 × 10 ^-3 cm ^-1 min ^-1 .

The photosensitive coating may include at least one photosensitive coating material and, if necessary, at least one additive or dopant made with the possibility of influencing the photoactivity of the coating compared to a coating without a dopant material. The photosensitive coating material may include at least one oxide, such as, but not limited to, one or more semiconductor oxides or oxides, for example, titanium oxides, silicon oxides, aluminum oxides, iron oxides, silver oxides, cobalt oxides, oxides chromium, copper oxides, tungsten oxides, zinc oxides, zinc / tin oxides, strontium titanate and mixtures thereof. The oxide may include oxides, superoxides or sub-oxides of the element. The oxide may be crystalline or at least partially crystalline. In one typical coating of the invention, the photosensitive coating material is titanium dioxide. Titanium dioxide exists in amorphous form and three crystalline forms, that is, in crystalline forms of anatase, rutile and brookite. The anatase titanium dioxide phase is especially useful because it has high photoactivity, also excellent chemical resistance and excellent physical durability. However, the rutile phase or combinations of anatase and / or the rutile phase with brookite and / or amorphous phases are also acceptable for the present invention.

Examples of dopants for a photosensitive coating useful for the invention include, but are not limited to, one or more of chromium (Cr), vanadium (V), manganese (Mn), copper (Cu), iron (Fe), magnesium (Mg) , scandium (Sc), yttrium (Y), niobium (Nb), molybdenum (Mo), ruthenium (Ru), tungsten (W), silver (Ag), lead (Pb), nickel (Ni), rhenium (Re) , tin (Sn) and / or any mixtures or combinations thereof in an elemental or ionic state.

In one non-limiting embodiment, the second coating 16 includes titanium dioxide with a thickness of more than 10 nm, for example, more than 20 nm, for example, more than 30 nm, for example, more than 40 nm, for example, more than 50 nm, for example, more than 60 nm, for example, more than 70 nm for example, more than 80 nm, for example, more than 90 nm, for example, more than 100 nm, for example, in the range of 10-150 nm.

In one non-limiting embodiment, the first coating 14 of the invention can provide an article 10 with a second titanium dioxide coating 16 with a visible reflectance of less than 23%, for example, less than 20%, for example, less than 19%, for example, less than 18%, for example, less than 17 %, for example, less than 16%, for example, less than 15%, for example, less than 14%, for example, less than 12%, for example, less than 11%, for example, less than 10%.

The first coating 14 and / or the second coating 16 can be formed at least on a portion of the substrate 12 by any conventional method, such as, but not limited to, pyrolysis of a pulverized substance, chemical vapor deposition (CVD), or vacuum deposition by magnetron sputtering ( MSVD). In the pyrolysis method of a pulverized substance, an organic or metal-containing precursor composition with one or more oxide precursors, for example, titanium dioxide and / or silicon dioxide and / or alumina and / or phosphorus and / or zirconia precursor materials, is introduced into the suspension for example, an aqueous or non-aqueous solution, and directed to the surface of the substrate, while the temperature of the substrate is high enough to cause decomposition of the precursor composition and the formation of coatings ytiya on the substrate. The composition may include one or more dopant materials. In the CVD method, the precursor composition is introduced into a carrier gas, for example nitrogen gas, and sent to a heated substrate. In the MSVD method, one or more metal-containing target cathodes is sprayed under reduced pressure in an inert or oxygen-containing atmosphere to spray the coating onto the substrate. The substrate may be heated during or after application to cause crystallization of the sprayed coating to form a coating.

In one non-limiting embodiment of the invention, one or more CVD coating devices may be used in one or more positions in a conventional float glass strip manufacturing process. For example, a CVD coating device can be used when a strip of float glass passes through a tin bath, after it leaves the tin bath, before it enters the lehr, when it passes the lehr, or after it leaves the lehr. Since the CVD method can be applied to a moving strip of float glass while resisting the harsh conditions associated with the production of a strip of float glass, the CVD method is particularly suitable for coating a strip of float glass in a bath with molten tin. US 4,853,257; 4,971,843; 5,536,718; 5,464,657; 5,714,199; and 5,599,387 describe a CVD coating device and methods that can be used in the practice of the invention for coating a strip of float glass in a molten tin bath.

In one non-limiting embodiment, one or more CVD coating devices may be located in a tin bath above the molten tin bath. When a strip of float glass moves through a tin bath, the vaporized precursor composition can be added to the carrier gas and directed to the upper surface of the tape. The precursor composition decomposes to form a coating (e.g., first coating 14 and / or second coating 16) on a strip. In one non-limiting embodiment, the coating composition is applied to the strip at a position where the strip temperature is less than 1300 ° F (704 ° C), for example, less than 1250 ° F (677 ° C), for example, less than 1200 ° F (649 ° C) for example, less than 1190 ° F (643 ° C), for example, less than 1150 ° F (621 ° C), for example, less than 1130 ° F (610 ° C), for example, in the range of 1190-1200 ° F (643-649 ° C). This is especially useful when applying a second coating 16 (for example, tin oxide doped with fluorine) with a lower specific surface resistance, since the lower the temperature of application, the lower the specific surface resistance obtained.

For example, to form a first coating 14 containing silicon dioxide and titanium dioxide, the composition includes both a silicon dioxide precursor and a titanium dioxide precursor. One non-limiting example of a silica precursor is tetraethylorthosilicate (TEOS).

Examples of titanium dioxide precursors include, but are not limited to, titanium oxides, sub-oxides, or superoxides. In one embodiment, the titanium dioxide precursor material may include one or more titanium alkoxides, such as, but not limited to methoxide, ethoxide, propoxide, titanium butoxide, and the like; or isomers thereof, for example titanium isopropoxide, tetraethoxide, and the like. Typical precursor materials suitable for carrying out the invention include, but are not limited to, tetraisopropyl titanate (TPT). Alternatively, the titanium dioxide precursor material may be titanium tetrachloride. Examples of alumina precursors include, but are not limited to, dimethylaluminum isopropoxide (DMAP) and tri-sec-butoxide aluminum (ATSB). In one non-limiting embodiment, dimethylaluminum isopropoxide can be prepared by mixing trimethylaluminum and aluminum isopropoxide in a 2: 1 molar ratio in an inert atmosphere at room temperature. Examples of phosphorus oxide precursors include, but are not limited to, terethylphosphite. Examples of zirconia precursors include, but are not limited to zirconium alkoxides.

The first coating 14 with a combination of silicon dioxide and titanium dioxide provides advantages over previous combinations. For example, a combination of a low refractive index material such as silicon dioxide (refractive index 1.5 at 550 nm) with a high refractive index material such as titanium dioxide (refractive index 2.4 at 550 nm) allows the refractive index of the first coating 14 vary between these two extremes, the change in the amount of silicon dioxide and titanium dioxide. This is especially useful for giving the first coating 14 properties of suppressing color background and rainbow.

However, usually the titanium dioxide deposition rate is much faster than silicon dioxide. Under normal deposition conditions, this limits the amount of silicon dioxide to no more than about 50 wt.%, Which in turn limits the lower refractive index range of the resulting silica / titanium dioxide coating. Therefore, the dopant material can be added to the composition of the silicon dioxide precursor and titanium dioxide to accelerate the deposition rate of silicon dioxide. The dopant is part of the resulting oxide mixture and, therefore, can be selected to provide improved performance characteristics of the resulting coating. Examples of dopants useful for carrying out the invention include, but are not limited to, materials containing one or more elements of phosphorus, aluminum and zirconium to form oxides of these materials in the resulting coating. Examples of phosphorus oxide precursor materials include triethyl phosphite. Examples of alumina precursor materials include tri-sec-butoxide aluminum (ATSB) and dimethylaluminium isopropoxide (DMAP). Examples of the zirconia precursor include zirconium alkoxide.

EXAMPLES

Example 1

This example illustrates the use of an intermediate layer of the invention as a background color suppression layer for an upper titanium dioxide layer. The intermediate layer is a combination of silicon dioxide, titanium dioxide and phosphorus oxide.

The intermediate layer is applied to the glass substrate by chemical vapor deposition using a laboratory coating device. Then, titanium dioxide is coated on the intermediate layer. Table 1 presents the coating configurations (composition and thickness) of samples 1-4. The intermediate layer is applied in the form of a multilayer film with three intermediate films; a first intermediate film on a glass substrate, a second intermediate film on a first intermediate film, and a third intermediate film on a second intermediate film. The multilayer configuration models an intermediate layer with a gradient.

Table 1 Sample 1 Sample 2 Sample 3 Sample 4 The thickness of the first intermediate layer [nm] 13 eleven 29th 13 Vol.% Phosphorus oxide in the first intermediate layer 5 10 5 5 Vol.% Silicon dioxide in the first intermediate layer 75 80 70 75 Vol.% Titanium dioxide in the first intermediate layer twenty 10 25 twenty The thickness of the second intermediate layer [nm] 23 33 21 27 Vol.% Phosphorus oxide in the second intermediate layer 2 2 2 2 Vol.% Silicon dioxide in the second intermediate layer 49 58 48 62 Vol.% Titanium dioxide in the second intermediate layer 49 40 fifty 36 The thickness of the third intermediate layer [nm] 21 eighteen fifteen 23 Vol.% Phosphorus oxide in the third intermediate layer 5 eleven 5 5 Vol.% Silicon dioxide in the third intermediate layer 75 80 70 70 Vol.% Titanium dioxide in the third intermediate layer twenty 9 25 25 The thickness of the upper coating of titanium dioxide [nm] 115 121 113 118

Table 2 presents the characteristics of color reflection for samples 1-4 and comparative samples (glass sheets coated with titanium dioxide without an intermediate layer). Color reflection data is simulated using conventional TFCalc® software for the coated side of the substrate at D65, observation at 10 °.

table 2 Sample 1 115 nm TiO ₂ Sample 2 121 nm TiO ₂ Sample 3 113 nm TiO ₂ Sample 4 118 nm TiO ₂ but* -6.6 17.17 -4.1 -3.5 -6.6 21.3 -4.2 10,4 b * -9.2 -41.4 -12.5 -38.7 -7.7 -40.9 -12.8 -40.7 L * 50.8 42,4 50.8 46.2 51.3 41.5 50.6 44.1

For this sample, the presence of an intermediate layer provides a generally lower (more negative) a * and higher (more positive) b * compared to a product without an intermediate layer.

Example 2

This example illustrates the use of an intermediate layer of the invention to provide enhanced photoactivity to the top layer of titanium dioxide. The intermediate layer includes silicon dioxide, titanium dioxide and phosphorus oxide.

Both the intermediate layer and the upper layer (titanium dioxide) are formed by chemical vapor deposition. Phosphorus oxide precursor is triethyl phosphite (TEP). Silicon dioxide precursor is tetraethylorthosilicate (TEOS). Titanium dioxide precursor in the intermediate layer and in the upper layer is tetraisopropyl titanate (TPT). Table 3 presents the deposition parameters for samples 5-9.

Table 3

Sample 5 Sample 6 Sample 7 Sample 8 Sample 9 TEP / TEOS molar ratio 1.25 1.25 0.5 0.5 N / a TPT / TEOS molar ratio 0.25 0.5 0.25 0.5 N / a Vol.% TEOS of the total flow rate for the intermediate layer 0.11 0.12 0.18 0.12 N / a Vol.% TEP of the total flow rate for the intermediate layer 0.14 0.15 0.09 0.06 N / a Vol.% TPT of the total flow rate for the intermediate layer 0,03 0.06 0.05 0.06 N / a Vol.% TPT of total consumption for functional coating 0.257 0.257 0.257 0.257 0.257

Table 4 presents the layer thickness for samples 5-9.

Table 4 Sample 5 Sample 6 Sample 7 Sample 8 Sample 9 Phosphorus Oxide [microgram / cm ² ] 1,5 2.1 1,5 1,2 N / a Titanium dioxide [microgram / cm ² ] 34,4 38,4 36.0 37.0 30,2 The thickness of the intermediate layer [nm] 37,4 98.9 52,5 83.3 0 The thickness of the functional coating of titanium dioxide [nm] 132 132 129 121 129

Table 5 presents the results of a conventional stearic acid test for samples 5-9. The stearic acid test is described in US 6,027,766, incorporated by reference. As you can see, products with an intermediate layer of the invention have a higher photocatalytic activity than products without an intermediate layer (example 9).

Table 5 SAR (× 10 ^-3 cm ^-1 min ^-1 ) Sample 5 121 Sample 6 121 Sample 7 112 Sample 8 92 Sample 9 61

Example 3

This example illustrates the use of an intermediate layer of the invention to reduce the surface resistivity of a fluorine doped tin oxide top layer.

The interlayer is silicon dioxide, titanium dioxide, phosphorus oxide supported by CVD. The precursors used are TEOS (silicon dioxide), TPT (titanium dioxide) and TEP (phosphorus oxide). The upper layers of tin oxide doped with fluorine of various thicknesses are applied to the intermediate layer and also to uncoated glass (as comparative samples). Both coatings are compared by R-Chek + surface resistivity measurement with a 4-point meter commercially available from Electronic Design To Market, Inc. The amount of [Sn], which corresponds to the thickness of the tin oxide coating doped with fluorine, is determined by the X-ray fluorescence method. Figure 2 shows that the specific surface resistance of tin oxide coatings doped with fluorine on the intermediate layer of the invention is on average 1-3 ohm / sq. lower than coatings of the same thickness of tin oxide doped with fluorine on glass. 2, open squares and a dashed line represent fluorine doped tin oxide on glass. Shaded circles and a solid line represent fluorine doped tin oxide on the intermediate layer of the invention. The intermediate layer (composition and thickness) is the same for each sample.

Example 4

A portion of the clear glass (12 inches by 24 inches; 30 cm by 61 cm) is coated using the CVD process with the precursors described above. Half of the glass is coated with fluorine doped tin oxide directly on the glass and the other half of the glass is coated with an intermediate layer of silicon dioxide, titanium dioxide, phosphorus oxide and an upper layer of tin oxide doped with fluorine. Samples are cut from each part of the glass sheet and analyzed as described below.

(1) X-ray fluorescence analysis (XRF) data

The XRF data in Table 6 show a similar amount of [Sn] for both coatings (slightly higher in the case of the FTO / UL multi-layer coating (tin oxide layer, fluorine doped / intermediate layer)).

Table 6 FTO only FTO / UL Idle experience [R] 0.09 0.56 0.09 [Til 0 1.87 0 [Sn] 145.8 147 0.2

(2) Haze and transmission

Samples are also checked for haze and transmittance. The results are presented in table 7. The transmission spectra are presented in figure 4. The haze is higher and the transmittance is also higher for fluorine doped tin oxide (PTO) / interlayer (UL) of the multilayer coating compared to fluorine doped tin oxide (FTO) coating directly on the glass. Thus, the intermediate layer of the invention also provides a method for increasing the haze and transmission of the coated article. This may be useful in the field of solar cells, where an increase in haze increases the length of absorption of electromagnetic energy, which, in turn, provides an increased possibility of absorption of electromagnetic energy.

Table 7 FTO only FTO / UL Dull 0.89% 1.77% Skipping 80.78% 81.37%

(3) Surface resistivity

The surface resistivity data is presented in table 8. The specific surface resistivity of the FTO / UL coating is 1.5 ohm / sq. lower than the FTO coating on glass.

Table 8 FTO only FTO / UL 13.55 ohm / sq 12.05 Ohm / sq.

(4) Coating Thickness

The FTO coating thickness is slightly higher in the case of FTO coating on glass (356 nm) compared to FTO on LJL (top FTO layer 334 nm) as determined by etching.

(5) Coating porosity

Coatings are analyzed using scanning electron microscopy (SEM). Numerous small holes are noted in the FTO coating directly on the glass. No holes are observed in the FTO / UL multi-layer coating.

(6) surface roughness

Surface roughness is analyzed using atomic force microscopy (AFM) over an area of 10 micrometers (μm) per 10 μm; 5 microns per 5 microns; and 1 μm per 1 μm. The results are presented in Table 9. The surface roughness is higher for FTO / UL multi-layer coatings than for FTO directly on glass. The increased surface roughness increases the dullness of the coating and therefore increases the absorption length of any incident electromagnetic energy.

Table 9 Sample RMS Roughness (nm) Ra Roughness (nm) FTO only 10 μm × 10 μm 13.39 10.69 FTO / UL 10 μm × 10 μm 17.45 13.74 FTO only 5 μm × 5 μm 12.53 9.99 FTO / UL 5 μm × 5 μm 18.03 14.09 FTO only 1 μm × 1 μm 8.99 7.18 FTO / UL 1 μm × 1 μm 9.96 8.03

Example 5

This example illustrates the effect of the middle layer of the invention on the reflection of a coated article.

Figure 4 shows the change in reflection for 10-120 nm TiO ₂ on transparent glass (open diamonds with a dashed line) and the same for the TiO ₂ layer on the intermediate layer of the invention on transparent glass. The intermediate layer is 13 nm, 75% SiO ₂ - 20% TiO ₂ - 5% P ₂ O _5/23 nm 49% SiO ₂ - 49% TiO ₂ - 2% P ₂ O _5/21 nm 75% SiO ₂ - 20% TiO ₂ - 5% P ₂ O ₅ (closed circles and solid line). The change in the thickness of TiO ₂ is 10-120 nm at intervals of 5 nm.

Figure 4 shows that when the thickness of the functional coating of TiO ₂ on the glass increases, the reflection varies over a wide range (i.e., within 11.7% <R <38.8%). However, when a functional TiO ₂ coating is applied to the intermediate layer, the reflection changes are much lower (i.e., within 17.2-27.4%). This shows that the change in the thickness of the top coating, the reflection of the multilayer coating as a whole with an intermediate coating is less sensitive than without an intermediate coating.

In some areas, reflection can be significantly reduced by the intermediate layer of the invention. Table 10 shows the difference in reflection on titanium dioxide at 55 nm and 165 nm.

Table 10 Reflection without middle layer Interlayer Reflection 55 nm TiO ₂ 38.8% 26.4% 165 nm TiO ₂ 35.6% 25.5%

Example 6

This example illustrates the effect of the middle layer of the invention on the color (e.g., a * and b *) of an article.

Figure 5 shows the change in a * and b * for 10-120 nm TiO ₂ on transparent glass (open diamonds with a dashed line) and for the same coating on the intermediate layer (13 nm 75% SiO ₂ - 20% TiO ₂ - 5% P ₂ O _5/23 nm 49% SiO ₂ - 49% TiO ₂ - 2% P ₂ O _5/21 nm 75% SiO ₂ - 20% TiO ₂ - 5% P ₂ O ₅₎ on the transparent glass (closed circles and solid line). The change in the thickness of TiO ₂ is 10-120 nm at intervals of 5 nm.

Figure 5 shows that when the thickness of the functional TiO ₂ coating increases, the color (a * and b *) of the TiO ₂ coating without an intermediate layer varies over a wide range (in the range of -24 <a * <+ 37 and -42 <b * < +34). However, when the TiO ₂ functional coating is applied to the intermediate layer, as described above, a * and b * change less (within -8 <a * <+ 12 and -10 <b * <+ 7). This means that as the thickness of the topcoat changes, the color of the entire multilayer coating with the intermediate coating layer of the invention is less sensitive than the coating without the intermediate layer.

Example 7

This example illustrates the effect of the gradient of the intermediate layer of silicon dioxide and titanium dioxide on the photocatalytic activity of titanium dioxide in the upper layer (120 nm thick).

Table 11 presents the compositions of the two binder layers with a gradient.

Table 11 The average TiO ₂ (%) The average SiO ₂ (%) Estimated Thickness (nm) XRD result but* b * R (%) Sample 10 68.9 31.1 23 Amorphous -0.937 -8.174 14.51 Sample 11 68.1 31.9 32 Amorphous -1.129 -7,904 15.81

Table 12 shows the effect of the two intermediate layers of table 11 on the photocatalytic activity of the upper layer of titanium dioxide 120 nm thick compared with the activity of titanium dioxide without intermediate layers. The unit [Ti] is microgram / cm ² .

Table 12 [Ti] specific XRF (μm / cm ² ) SAR (× 10 ^-3 cm ^-1 min ^-1 ) [Ti] intermediate layer [Ti] intermediate layer + top layer [Ti] top layer Sample 12 TiO ₂ coating on sample 10 56.5 4.10 34.60 30.50 Sample 13 TiO ₂ coating on sample 11 57.7 4.60 35.40 30.80 Sample 14 TiO ₂ coating on clear glass 51.6 N / a 32.70 32.70

Those skilled in the art will readily recognize that modifications to the invention can be made without departing from the principles disclosed in the foregoing description. Accordingly, certain embodiments described in detail in the application are illustrative only and do not limit the scope of the claims of the invention, which is fully set forth in the appended claims and any equivalents thereof.

Claims (14)

1. The product is coated, including:
a substrate;
a first coating formed on at least a portion of the substrate, which includes oxides of at least two elements selected from P, Si, Ti, Al and Zr; and
a functional coating formed at least in part of the first coating,
wherein the first coating is a multilayer coating containing:
the first layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of titanium dioxide is in the range from 10 to 25 vol.%;
a second layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of titanium dioxide is in the range from 36 to 50 vol.%;
a third layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of titanium dioxide is in the range from 9 to 25 vol.%. 2. The product according to claim 1, in which the first coating further comprises at least Al oxides. 3. The product according to claim 1, in which the functional coating contains oxides of one or more elements selected from Zn, Fe, Mn, Al, Ce, Sn, Sb, Hf, Zr, Ni, Bi, Ti, Co, Cr, Si and In or an alloy of two or more of these materials. 4. The product according to claim 3, in which the functional coating includes at least one dopant selected from F, In, Al and Sb. 5. The product according to claim 4, in which the functional coating includes tin oxide doped with fluorine. 6. The product according to claim 4, in which the functional coating contains titanium dioxide. 7. The product according to claim 6, in which the thickness of the titanium dioxide is from 113 to 121 nm. 8. The product according to claim 1, in which the color of the product is in the range of -10≤a * ≤2 and -15≤b * ≤0. 9. The product of claim 8, in which a * is in the range from -8 to -4.4, b * is in the range from -12.6 to -5.2 and L * is in the range from 50.5 to 52, 3. 10. The product is coated, including:
a substrate;
a first coating formed on at least a portion of the substrate, which includes oxides of at least two elements selected from P, Si, Ti, Al and Zr; and
a functional coating formed at least in part of the first coating,
wherein the first coating is a multilayer coating containing:
the first layer, comprising from 5 to 10 vol.% phosphorus oxide, from 70 to 80 vol.% silicon dioxide and from 10 to 25 vol.% titanium dioxide, having a thickness in the range from 11 to 29 nm:
a second layer comprising 2 vol.% phosphorus oxide, from 48 to 62 vol.% silicon dioxide and from 36 to 50 vol.% titanium dioxide, having a thickness in the range from 21 to 22 nm; and
the third layer, comprising from 5 to 11 vol.% phosphorus oxide, from 70 to 80 vol.% silicon dioxide and from 9 to 25 vol.% titanium dioxide, having a thickness in the range from 15 to 23 nm. 11. A coated product, including:
glass substrate;
a first coating formed on at least a portion of the substrate, which includes oxides of at least two elements selected from P, Si, Ti, Al and Zr; and
a functional coating formed at least on a portion of the first coating that contains an oxide selected from the group consisting of titanium dioxide and tin oxide doped with fluorine;
wherein the first coating is a multilayer coating containing:
the first layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of silicon dioxide is in the range from 70 to 80 vol.%;
a second layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of silicon dioxide is in the range from 48 to 62 vol.%; and
the third layer, including phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of silicon dioxide is in the range from 70 to 80 vol.%. 12. A method of manufacturing a coated product, comprising:
obtaining a glass substrate;
forming a first coating on at least a portion of the glass substrate by chemical vapor deposition (CVD) by directing the first coating composition onto the glass substrate, the first coating composition comprising oxides of at least two elements selected from P, Si, Ti, Al and Zr; and
the formation of a functional coating, at least on the part of the first coating, in which the first coating is a multilayer coating containing:
the first layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of titanium dioxide is in the range from 10 to 25 vol.%;
a second layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of titanium dioxide is in the range from 36 to 50 vol.%; and
a third layer comprising phosphorus oxide, silicon dioxide and titanium dioxide, in which the content of titanium dioxide is in the range from 9 to 25 vol.%. 13. The method according to item 12, in which the first coating is applied in the form of a coating with a gradient. 14. The method according to item 12, in which the first coating is applied in the form of a multilayer coating.

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