Improving glass strength and fracture toughness with non-brittle coatings

Abstract

The present invention relates to a coating for improving glass strength and fracture toughness and its preparation, comprising a hydrolysis polycondensation product of one or more alkoxysilanes with one or more metal oxides and / or metal alkoxides in the presence of water and a catalyst. The present invention also relates to the use of the coating for repairing damaged silica-containing materials.

Description

[Technical field]

[0001] The present invention relates generally to methods and systems for improving glass strength and fracture toughness or for repairing damaged glass or silica-containing materials. In particular, the present invention relates to the use for these purposes of coatings comprising hydrolysis polycondensation products of one or more alkoxysilanes and one or more metal or metalloid oxides and / or metal or metalloid alkoxides in the presence of water and a catalyst. [Background technology]

[0002] Glass is more susceptible to atmospheric moisture (e.g., in temperate climates, 77 ppm (0.1 g / Nm) in extremely cold, dry winter weather). 3 corresponds to 20% relative humidity at -30°C), and up to 90,000ppm (115g / Nm2) in extremely humid summer weather. 3 Exposure to high temperatures (up to +60°C, which corresponds to 100% humidity) and high formation temperatures where water or hydroxyls are chemically active and break the Si-O-Si bonds by generating two terminal Si-OH bonds, weakens the structure and establishes a mechanism that finds hydroxyls at the crack tips of all investigated cracks and ultimately leads these cracks to fracture, resulting in a significant reduction in glass strength. The above behavior is due to the presence of surface microcracks that are generated within a very short time (e.g., within milliseconds or seconds) during high temperature formation and the propagation of the cracks promoted by atmospheric humidity.

[0003] Various methods are used in industry to improve glass strength, including ion exchange (chemical tempering), heat tempering, lamination, etc. All of these methods have various drawbacks and limitations. For example, the widely used ion exchange and heat tempering methods do not work below a certain glass thickness and have compositional limitations.

[0004] The glass is cooled rapidly from the forming (molten glass temperature) to room temperature or to the glass transition temperature, T gBy cooling to temperatures significantly below (hard glass temperature), repairing defects caused by the enormous stresses set up between the "outer" surface and the rapidly contracting interior in the transition from the liquid to the "solid" state towards the equilibrium (ambient) temperature, these stresses are relieved by the generation of micro surface cracks initiated by such stresses, with water molecules present in the surrounding air being the main cause of crack propagation, all these effects reducing the strength of the glass product by up to 200 times, in other words from 100% of the theoretical mechanical strength to about 0.5% of the theoretical mechanical strength in practice.

[0005] The three traditional methods of forming a protective compressive layer depend on the physical thickness of the glass on which the compressive layer is formed. As the glass gets thinner, it passes the limit where the compressive layer becomes meaningful. Cover glass was 0.7mm, but is now moving towards 0.4mm and even 0.2mm. These thickness reductions are approaching the limit of usefulness of ion exchange. Furthermore, in the example of smartphones such as the iPhone, the electronic circuitry is printed on special glass that does not contain alkalis. It is precisely the alkalis, e.g., but not limited to, lithium, sodium and potassium, that play the major role in chemical tempering. However, these same ions attack the transistors, liquid crystals and electronic circuitry required for large flat screen displays. A typical flat glass single sheet substrate (typically soda lime or borosilicate) is traditionally manufactured in thicknesses of 3mm to 15mm, but is trending downwards towards less than 3mm. For flat glass with a thickness of 2mm or less, tempering is reaching its physical limit, e.g., glass less than 3mm is difficult to temper as ESG, so for thinner glass up to 2mm in thickness, TVG is the traditionally possible tempering grade.

[0006] Inorganic coatings are inherently brittle and tend to eventually develop microcracks of themselves during use. Non-brittle organic coatings, on the other hand, are softer and therefore more susceptible to optical degradation due to wear during use. To date, the formation of hydroxyl groups (OH -No commercially available coating has the ability to create covalent bonds with the glass matrix and thereby repair defects by breaking down the SiO2 bonds and allowing crosslinking to O-Si-O (or other) covalent bonds. It is extremely difficult to achieve both hardness and non-brittleness in the same material. Therefore, there is a need for a coating that will repair the glass surface from defects introduced in high temperature forming by improving the strength of the glass product, while at the same time providing sufficient abrasion resistance. Summary of the Invention

[0007] A first aspect provided herein is a method for preparing a coating for improving glass strength and fracture toughness of glass, the method comprising: a) in the presence of 20% by weight or less of water, 95% by weight or less of alcohol and 1% by weight or less of a catalyst, 5 to 95% by weight of a compound of the general formula R x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes, each independently selected from an alkyl, an alkyl group, or an isomer or polyvalent group thereof, and x is an integer from 0 to 3; and up to 40% by weight of one or more metal or semi-metal oxides and / or one or more metal or semi-metal alkoxides. b) a composition comprising 20-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 80% by weight or less of an alcohol, 20% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 50% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. mixing the The weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0008] A second aspect provided herein is a method for preparing a coating for improving glass strength and fracture toughness of glass, the method comprising: a) a composition comprising 25% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides in the presence of 20% by weight or less of water and 60 to 95% by weight of alcohol; b) 5 to 95% by weight of a compound of general formula R x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes, each independently selected from an alkyl group, an isomer or polyhydric group thereof, and x is an integer from 0 to 3; 5 to 70% by weight of an alcohol; 20% by weight or less of water; and 0.5% by weight or less of a catalyst; c) A composition comprising 10 to 50% by weight of one or more metal or semimetal oxides and / or one or more metal or semimetal alkoxides, 10 to 90% by weight of water, and 100% by weight or less of alcohol. mixing the The weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0009] In one embodiment of the present invention, the catalyst is nitric acid, aqua regia or hydrofluoric acid or a combination thereof.

[0010] In one embodiment of the invention, R is C 1~18 Alkyl, C 1~18 Heteroalkyl, C 1~18 Alkoxy, C 2~18 Alkene, Phenyl, R 2 -(CH2) n -, cycloalkyl and aryl groups, and R 2 -O-(CH2) n or an isomer or multivalent form thereof; R 1 is C 1~18alkyl or cycloalkyl, or isomers or polyvalent forms thereof; R 2 is hydrogen, C 1~18 Alkyl, (C2H4O)-(R 3 ) m -, C 2~18 R is independently selected from an alkene, or an isomer or multivalent form thereof; 3 is C 1~18 alkyl or an isomer or polyvalent form thereof; n is an integer from 0 to 10; and m is an integer from 0 to 10.

[0011] In a further embodiment of the invention, the one or more alkoxysilanes are selected from β-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropylsilane, methoxyethylsilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane and triethylmethoxysilane.

[0012] In a further embodiment of the invention, the one or more metal or metalloid oxides and / or the one or more metal or metalloid alkoxides are selected from oxides and / or alkoxides of boron, aluminum, gallium, indium, thallium, silicon, germanium, tin, lead, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, copper, silver, gold, palladium, platinum, zinc, cobalt, rhodium, iridium, selenium, tellurium, or polonium, or other species.

[0013] In a further embodiment of the invention, the alkoxysilane is β-glycidoxypropyltrimethoxysilane or γ-glycidoxypropyltrimethoxysilane and the metal alkoxide is selected from boron alkoxides, titanium alkoxides and silicon alkoxides, or mixtures thereof.

[0014] In a third aspect, the present invention relates to a coating prepared by the methods provided herein.

[0015] In a fourth aspect, the present invention provides a method for producing a composition comprising the steps of: a) 50 to 85% by weight of a compound of the general formula R in the presence of 10% by weight or less of water, 30% by weight or less of alcohol and 1% by weight or less of a catalyst. x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes of the formula (I) (independently selected from alkyl, aryl, aryls, arylalkyl, aryls ... b) a composition comprising 20-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 80% by weight or less of an alcohol, 20% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 50% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. A mixture of The weight percentages of a), b), c) and mixtures thereof each relate to the coating, which total 100% by weight.

[0016] In a fifth aspect, the present invention relates to the use of a coating as provided herein for improving glass strength and fracture toughness of glass, wherein the glass strength and fracture toughness are improved by repairing cracks in the surface of the glass.

[0017] In a sixth aspect, the present invention relates to the use of the coatings provided herein to repair damaged silica-containing materials, including, but not limited to, any glass.

[0018] In one embodiment, the present invention relates to the uses provided herein, wherein the silica-containing material comprises glass, ceramic, glass-ceramic, quartz, cement and concrete.

[0019] In one embodiment, the present invention relates to the use as provided herein, wherein one or more further coatings are applied for abrasion resistance, chemical resistance, birefringence, altering the refractive index, increasing hardness, protection from voltage induced degradation of photovoltaic or semiconductor devices, controlled increase in mechanical strength, improved hydrophobization to repel water, improved oil repellency, protection against damage from fouling, weathering and / or energy release at the point of failure.

[0020] In a further embodiment, the present invention relates to the use as provided herein, wherein the one or more coatings are applied by dip coating, spray coating, vapor deposition, atomization, plasma external vapor deposition, chemical vapor deposition, plasma induced vapor deposition, penetration, immersion, suspension and / or plasma enhanced vapor deposition.

[0021] In a further embodiment, the present invention relates to the use as provided herein, wherein one or more coatings are applied in a controlled atmosphere, at subatmospheric or elevated pressure, and / or at temperatures above or below atmospheric temperature.

[0022] In a further embodiment, the present invention relates to the use as provided herein, wherein the controlled atmosphere comprises conditioned air having a dew point below -20°C (253K), -50°C (223K) or less, -78.5°C (194.7K) or less, -195.8°C (77.35K) or less, 27K or less, or 4K.

[0023] In a further embodiment, the present invention relates to the use as provided herein, wherein the controlled atmosphere comprises an industrial or specialty gas.

[0024] In a further embodiment, the present invention relates to a process in which the pressure during any of the steps involved in the present invention is at or below ambient pressure, at or below 950 hPa, below 500 hPa, below 100 hPa, below 10 hPa, below 1 hPa, below 0.1 Pa, below 10 -6 Less than Pa, or even 10 -9 The present invention relates to the uses provided herein, including absolute pressures of less than 1 Pa.

[0025] In a further embodiment, the present invention relates to the use as provided herein, wherein unused coating is removed from the glass surface.

[0026] In a further embodiment, the present invention relates to the use as provided herein, wherein the unused coating is removed by immersing the coated glass in a solvent or rinsing the coated glass with a solvent.

[0027] In a further embodiment, the present invention relates to the uses provided herein, wherein the improvement in glass strength is 50-5000%, greater than 5000% or greater than 10000%.

[0028] In a further embodiment, the present invention relates to the use as provided herein, wherein devitrification is avoided.

[0029] In a further embodiment, the present invention relates to the use as provided herein, wherein the damage is caused by physical and / or chemical impact.

[0030] In a further embodiment, the present invention relates to the use as provided herein, wherein prior to applying the coating, the glass surface, optionally including the edges, is pre-treated with hydrofluoric acid, mechanical edge grinding, flame polishing, laser treatment and / or any other edge treatment technique.

[0031] In a further embodiment, the present invention relates to a method for preparing a glass having a transition temperature (T g) at least 300 K lower than the temperature at which the substrate is exposed to the heat.

[0032] In a further embodiment, the present invention relates to the use as provided herein, wherein a temperature of at least 30° C. is applied to the coated glass or coated silica-containing material for curing.

[0033] In a further embodiment, the present invention relates to the use as provided herein, wherein the coated glass or coated silica-containing material is exposed to waves of suitable frequencies and / or wavelengths including subsonic, sonic, supersonic, infrared, visible range, ultraviolet range, extreme ultraviolet range and / or wavelengths lower than the extreme ultraviolet range, and / or waves of any other suitable frequencies and / or wavelengths that cause the desired reaction between the reaction partners depending on the physical properties, any frequency allowing the curing of the coating on the glass substrate, silica-containing material.

[0034] In a further embodiment, the present invention relates to the use as provided herein, wherein the glass or coated silica-containing material is exposed to tempering before or after coating.

[0035] In one embodiment, the invention relates to the use of the coatings provided herein, where the silica-containing material is in the form of a porous material or powder and is partially or totally impregnated with the coating throughout the pores or within the powder clusters.

[0036] In a seventh aspect, the present invention relates to a glass product or product made from a silica-containing material prepared by the uses described herein.

[0037] In further embodiments, new or returnable bottles (containers) having physical or chemical surface damage can be repaired by preparation with any selected use described herein, such that such bottles can be reused for at least one additional cycle, e.g., another 5 or 10 cycles, or more cycles. [Brief description of the drawings]

[0038] [Figure 1a] FIG. 1a shows a reaction scheme of certain alkoxysilanes with water in the presence of an acid catalyst. [Figure 1b] FIG. 1b illustrates the reaction of the reaction product of FIG. 1a with certain titanium alkoxides. [Diagram 2] FIG. 2 is a schematic diagram of the chemical bonding of a coating of the present invention on a glass surface (a) and the immobilization of sodium ions by boron coordination changes (b). [Diagram 3] FIG. 3 shows the intensity distribution curves of the uncoated and coated samples. [Figure 4] FIG. 4 shows a graph illustrating the increase in strength, as measured by the "cone crack load" method, of float glass samples when coated on the tin and air surfaces. [Figure 5a] FIG. 5a shows the fracture pattern of uncoated glass. [Figure 5b] FIG. 5b shows an exemplary fracture pattern of glass coated according to the present invention. [Figure 6] FIG. 6 shows sodium leaching from coated and uncoated glass, the coating containing boron. [Figure 7] FIG. 7 shows a sample of glass made entirely using the sol-gel method of the present invention. [Figure 8] FIG. 8 shows glass damaged by Vickers indentation test (different illumination under microscope). [Figure 9] FIG. 9 shows the Vickers indentation sample images of uncoated (left) and coated (far right) samples, and the average failure test results. [Figure 10] FIG. 10 is a surface analysis of the Vickers indentation on the float glass sample. [Figure 11] FIG. 11 shows the breakage test values ​​for (1) uncoated glass without mechanically induced defects, (2) coated glass with mechanically induced defects, and (3) glass samples with mechanically induced defects that were coated after the application of the defects. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] The present invention provides sol-gel compositions in the form of coatings provided herein that are organic-inorganic polymers that transform into true glassy amorphous networks to repair defects introduced by quenching and differential expansion. In particular, the present invention provides a method for preparing a coating for improving glass strength and fracture toughness of glass, the method comprising: a) in the presence of 20% by weight or less of water, 95% by weight or less of alcohol and 1% by weight or less of a catalyst, 5 to 95% by weight of a compound of the general formula R x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes, each independently selected from an alkyl, an alkyl group, or an isomer or polyvalent group thereof, and x is an integer from 0 to 3; and up to 40% by weight of one or more metal or semi-metal oxides and / or one or more metal or semi-metal alkoxides. b) a composition comprising 20-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 80% by weight or less of an alcohol, 20% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 50% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. mixing the the weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0040] In one embodiment, the method comprises: a) in the presence of 15% by weight or less of water, 50% by weight or less of alcohol and 1% by weight or less of a catalyst, 20 to 80% by weight of a compound of the general formula R x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes, each independently selected from an alkyl, an alkyl group, or an isomer or polyvalent thereof, and x is an integer from 0 to 3; and up to 30% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides. b) a composition comprising 30-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 60% by weight or less of an alcohol, 10% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 30% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. mixing the The weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0041] In yet another embodiment, the method comprises: a) in the presence of 10% by weight or less of water, 40% by weight or less of alcohol and 1% by weight or less of a catalyst, 50 to 80% by weight of a compound of the general formula R x Si(OR 1 ) 4-x(wherein R is an organic radical; R 1 is hydrogen and C 1~18 a composition comprising one or more alkoxysilanes of the formula (I) (independently selected from alkyl, alkyl group, or isomers or polyvalent groups thereof, and x is an integer from 0 to 3) and 25% by weight or less of one or more metal or semi-metal oxides and / or one or more metal or semi-metal alkoxides; b) a composition comprising 40-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 50% by weight or less of an alcohol, 10% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 25% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. mixing the The weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0042] In yet another embodiment, the method comprises: a) 60 to 75% by weight of a compound of the general formula R in the presence of 5 to 10% by weight of water, up to 30% by weight of an alcohol and up to 1% by weight of a catalyst. x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes of the formula (I) (independently selected from alkyl, aryl, aryls, arylalkyl, aryls ... b) a composition comprising 50-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 40% by weight or less of an alcohol, 5% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 20% ​​by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. mixing the The weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0043] The absolute weight of each of the compositions a), b), and c) is the total weight when the relative weight of a)+b)+c) is taken as 100%, and the occupancy rate of each of the compositions a), b), and c) is typically in the range of 20-70% by weight for a), 5-40% by weight for b), and 0-50% by weight for c). In one embodiment of the present invention, the composition is used in a ratio of 30-65% by weight of the composition a), 5-35% by weight of the composition b), and 50% by weight or less of the composition c). For example, the composition is used in a ratio of 40-65% by weight of the composition a), 10-35% by weight of the composition b), and 50% by weight or less of the composition c). In another embodiment, the composition is used in a ratio of 40-45% by weight of the composition a), 10-15% by weight of the composition b), and 10-50% by weight of the composition c). The sum of the amounts of the compositions a), b), and c) is 100% by weight.

[0044] The present invention recognizes that upon contact with moisture-laden air at forming temperatures, glass strength is rapidly reduced by water, which, if chemically active, will form chemical bonds with the glass, breaking Si-O-Si bonds to form terminal Si-OH bonds that are weak points in the surface structure, and by this handling will force the development of surface microcracks. Known and implemented glass strengthening methods work by creating a compressive surface layer that must be overcome before fracture can occur. The present invention describes the first method to actually repair surface defects common to all glass produced in the last 5,000 years. The use of the coatings provided herein significantly improves glass strength and fracture toughness. The coatings are covalently bonded to the surface of the glass upon application, eliminating existing surface microcracks and their future formation, as well as avoiding strength degradation due to handling and atmospheric moisture. Since the surface cracks or defects have small, e.g., micrometer-scale or nanometer-scale or even smaller, diameters, after the coating penetrates the surface cracks, it can be removed with a solvent before thermal curing, and the surface is intact like new glass, but the microcracks retain enough polymer to be converted to glass during curing and repair the surface defects, i.e., incorporated into the glass matrix by the formation of covalent bonds between one or more coatings and the glass material. Thus, without wishing to be bound by theory, the covalent bonds between the coating and the glass are formed by a chemical reaction by decomposing (terminal) hydroxyl groups (OH-) on the glass surface, allowing crosslinking to [-O-Si-] covalent bonds or any other covalent bonds. In other words, the terminal hydroxyl groups of the uncoated glass surface are decomposed by chemical reaction with one or more coatings, and covalent bonds are formed between the reactive moieties of one or more coatings and the oxygen atoms of the glass surface resulting from the decomposition of the hydroxyl groups. Any coating (coating solution) of the present invention penetrates into the microcracks in the glass surface and attaches to the terminal hydroxyl groups of the glass matrix, which in a subsequent step decomposes these hydroxyl groups and creates new covalent chemical bonds.Furthermore, the coating has the surprising property of not being brittle (does not develop surface cracks of its own), but is practically as hard and abrasion resistant as an unaltered glass surface. Thus, the use of the coating, i.e., a hybrid copolymer (polymer of organic and inorganic elements), provides maximum hardness with sufficient ductility to prevent crack propagation. The coating has the additional advantage of being soluble to facilitate coating and curing.

[0045] One limiting factor in producing true glass is the liquidus temperature at which the first crystals form on cooling or the last crystals dissolve on heating. Of the periodic table and list of metal oxides that can be used to produce glass, there is a large limit to the amount of these metal oxides that will form a viable glass without devitrifying (i.e., without crystallizing). The present invention greatly increases the availability and concentration of metal oxides that can be incorporated into thin film or bulk glass products. Since the transformation to true amorphous glass occurs at or below 500°C, this is below the temperature at which devitrification is a concern. This new material can produce glasses with very high refractive indices or other physical properties that were previously unavailable to scientists studying true inorganic glasses. An example can be taken from Figure 7, where the glass on the left is an alumina sol-gel with 64% voids but with diameters less than 50 Å (the sample on the right was immersed in isopropyl alcohol to give more transparency and the photo was taken immediately after immersion. Ethanol is even better due to its smaller molecular size). Thus, according to the present invention, devitrification is avoided or even eliminated. This sample was produced exclusively using the sol-gel method without a coating, but shows that this process can be used to produce coatings with very high Al2O3 contents that are not possible using normal glass melting processes because they would devitrify or crystallize.

[0046] According to the invention, the functionality and versatility of glass can be increased to such an extent that it can be replaced by other materials. As an example, the increase in the mechanical strength of glass allows the thickness of the container glass walls to be significantly reduced, which reduces the weight, resulting in a significant carbon footprint reduction since the amount of energy required to produce the container is substantially reduced. The reduction in weight also contributes to the possibility that plastic bottles, which exist and pollute our planet, can be eliminated or at least largely replaced. Furthermore, the productivity of glass furnaces is significantly increased, since more containers can be produced per unit of glass melting area.

[0047] In a further embodiment, prior to applying the coating, the surface of the glass substrate is treated with hydrofluoric acid to remove a first layer of the glass surface, reduce the depth of microcracks, and remove some of the terminal Si-OH bonds. In this embodiment, the coating applied after this treatment provides improved effectiveness of crack penetration, resulting in a further improved increase in mechanical strength.

[0048] In the present invention, any of the above or described herein is also suitable for silica-containing materials, as defined below.

[0049] In one aspect of the present invention, it is also possible to repair damaged silica-containing materials. Such silica-containing materials may be, but are not limited to, glass, ceramic, glass-ceramic, quartz, cement and concrete. The silica-containing material may be in any suitable form, such as, but not limited to, a solid form, a compressed or sintered powder, or a porous material. In a preferred embodiment, the silica-containing material is glass. In the process of repairing such silica-containing materials, cracks and / or damage on the surface, or damage to a substantial depth of the silica-containing material - with any exit to the surface - can be repaired using the coating of the present invention described herein, so that the glass recovers at least a large part of its previous properties, such as glass strength and fracture toughness, or these properties are even improved. According to the present invention, for example, damage caused by physical and / or chemical impact can be repaired. Non-limiting examples of such damage are, for example, impact by hailstones, gravel, rocks, stone impacts or other physical objects, temperature difference impact, fatigue failure, for example, due to alternating stress, or failure caused by any other physical impact on glass, windows, photovoltaic panels, automotive glass (for example, windshields), container glass, tubular glass, crystal glass, tableware glass, heat-resistant glass, glass ceramic, optical glass, or any other glass substrate, quartz substrate, ceramic substrate, or cement or concrete-containing substrate. In another aspect of the present invention, surface damage caused during various use cycles of returnable bottles (containers), such surface defects, can be repaired by applying the present invention so that the original mechanical strength of the bottles (containers) can be restored by repairing the surface defects. Damage caused by other impacts is also encompassed by the present invention.

[0050] As described above, the coating of the present invention, when applied and optionally cured, can significantly, nearly completely or completely restore the properties of damaged silica-containing materials. For example, the mechanical strength of glass can be restored to at least 50%, such as at least 60%, at least 75%, at least 80%, at least 90%, 100%, or even more than 100% of the remaining mechanical strength of the previously damaged glass. The same is true for other silica-containing materials.

[0051] The coatings of the present invention can repair damaged silica-containing materials within the range of visibility of the naked eye and / or even within the range of visibility of a magnifying device such as a microscope.

[0052] In the first step of the method of the present invention, composition a) is prepared by mixing the components in a suitable container. In the presence of water, the alkoxysilane compound is partially hydrolyzed using a catalyst. The water in this step and all other steps of the method of the present invention can be any water, such as deionized water, distilled water, multiple distilled water (e.g., so-called "double distilled" water), heavy water, etc. At most, a stoichiometric amount of water is used, such as 1 mole of water per mole of reactive group. The catalyst can be selected from any catalyst suitable for this type of chemical reaction. In the present invention, the catalyst may be consumed during the reaction. For example, the catalyst includes (chemical reaction) initiators or acids, such as, but not limited to, nitric acid, aqua regia, hydrochloric acid, sulfuric acid, and mixtures thereof. In a preferred embodiment, the catalyst is nitric acid or aqua regia or hydrofluoric acid or a combination thereof.

[0053] This reaction results in the formation of one or more metal or metalloid oxides and / or metal or metalloid alkoxides and / or hydroxyl groups which react with the silane.

[0054] The hydrolysis reaction must be allowed sufficient time to consume all the water introduced into the system, i.e., so that no free water remains in the solution for the next reaction step. This reaction consumes all the water added in a short time and forms terminal hydroxy bonds. Excessive time between the two reactions should be avoided, as the hydrolyzed alkoxysilanes will slowly self-polymerize and adversely affect homogeneity. According to one embodiment of the present invention, the reaction time between the alkoxysilane and the water may be less than 60 minutes, such as less than 30 minutes, for example less than 20 minutes, less than 15 minutes, less than 10 minutes, less than 5 minutes, or less than 1 minute. For example, the reaction time may be 5 to 10 minutes, for example 6 to 10 minutes, or 8 to 10 minutes. In one embodiment, the reaction time is less than 10 minutes. In a further embodiment, the composition a) may be left overnight.

[0055] Generally, step a) can be carried out under ambient conditions, such as at room temperature. In a preferred embodiment, step a) can be carried out under a controlled atmosphere, such as a water vapor-free atmosphere, an oxygen-free atmosphere, or an inert atmosphere as described below.

[0056] In a second step, composition b) is premixed and gradually added to the mixture obtained in step a) of the method of the invention. In order to prevent significant self-polymerization of the partially hydrolyzed alkoxysilanes, the metal or semimetal oxide and / or metal or semimetal alkoxide must be introduced within a critical time. Figure 1b shows an exemplary reaction between the compound obtained in Figure 1a and Ti(OC3H7)4. Under such circumstances, for example, when titanium alkoxide is introduced into the solution, it can only react with the hydroxyl groups of glycidoxypropyltrimethoxysilane, thereby linking the organic and inorganic components in the copolymer chain. This results in the formation of oxide bonds between the organic and inorganic groups in the hybrid polymer solution (soluble form). In a different embodiment, composition b) is not premixed but is mixed into composition a) by spraying the pure composition b) into a pure spray mist of composition a) or vice versa, when the components are applied to the glass of the glass-ceramic substrate.

[0057] At this stage, it is important that there should be no free water in the mixture at the end of the first part of the reaction. Otherwise, the metal alkoxide will react with the free water and condense or precipitate separately. Secondly, and importantly, excessive time between the two reactions should be avoided, as the hydrolyzed alkoxysilane will slowly self-polymerize, adversely affecting homogeneity. The second part of the reaction requires a minimum time, but unlike the first part of the reaction, no maximum time is required. Most of the remaining alkoxy bonds from the copolymer can be removed at any time by the addition of further water. Further water addition removes excess organic groups and promotes the formation of longer chains of oxide network, thereby forming a hard and wear-resistant structure. However, there is a limit to the addition of water, for example, about 50% of the total volume, that the system can tolerate without causing turbidity of the solution due to the solvent's insolubility in water.

[0058] After this coupling, the product shown in Figure 1b is fully hydrolyzable to produce a homogeneous inorganic-organic copolymer without the risk of separation or precipitation upon further addition of water. The resulting polymer is soluble in water and alcohol, so it can be diluted to any concentration to deposit a desired film thickness on glass.

[0059] Step b) of the method of the present invention can be carried out in less than 60 minutes, such as less than 30 minutes, such as less than 20 minutes, less than 15 minutes, less than 10 minutes, less than 5 minutes, or less than 1 minute. For example, the reaction time may be 5 to 10 minutes, such as 6 to 10 minutes, or 8 to 10 minutes. With respect to step a), the reaction can be carried out at ambient conditions, such as at room temperature. In a preferred embodiment, step b) can be carried out under a water vapor-free or inert atmosphere, such as an oxygen-free or inert atmosphere as described below.

[0060] In a third step, composition c) is added and the reaction mixture is stirred. This third step c) may be an optional step in the preparation method of the present invention.

[0061] Step c) can also be carried out in less than 60 minutes, such as less than 30 minutes, such as less than 20 minutes, less than 15 minutes, less than 10 minutes, less than 5 minutes, or less than 1 minute. For example, the reaction time can be 5 to 10 minutes, such as 6 to 10 minutes, or 8 to 10 minutes. For steps a) and b), the reaction can be carried out under ambient conditions, such as room temperature. In a preferred embodiment, step a) can be carried out under a water vapor-free atmosphere, an inert atmosphere, such as an oxygen-free atmosphere or an inert atmosphere, as described below.

[0062] In another aspect, the present invention is a method for preparing a coating for improving glass strength and fracture toughness of glass, the method comprising: a) a composition comprising 25% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides in the presence of 20% by weight or less of water and 60 to 95% by weight of alcohol; b) 5 to 95% by weight of a compound of general formula R x Si(OR 1 ) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes of the formula (I) (independently selected from alkyl, alkyl group, or isomers or polyhydric groups thereof, and x is an integer from 0 to 3), 5 to 70% by weight of an alcohol, 20% by weight or less of water, and 0.5% by weight or less of a catalyst; and c) A composition comprising 10 to 50% by weight of one or more metal or semimetal oxides and / or one or more metal or semimetal alkoxides, 10 to 90% by weight of water, and 100% by weight or less of alcohol. mixing the the weight percentages of a), b), c) and mixtures thereof each total 100% by weight.

[0063] In this aspect of the invention, the same reaction conditions as described above are generally used. The absolute weights of the individual compositions a), b), and c) are the total weight when the relative weight of a)+b)+c) is taken as 100%, and the occupancy of a), b), and c) is typically in the range of 20-70% by weight for a), 5-40% by weight for b), and 0-50% by weight for c). In one embodiment of the invention, the composition is used in a ratio of 30-65% by weight of composition a), 5-35% by weight of composition b), and 50% by weight or less of composition c). For example, the composition is used in a ratio of 40-65% by weight of composition a), 10-35% by weight of composition b), and 50% by weight or less of composition c). In another embodiment, the composition is used in a ratio of 40-45% by weight of composition a), 10-15% by weight of composition b), and 10-50% by weight of composition c). The sum of the amounts of compositions a), b) and c) is 100% by weight.

[0064] In one embodiment of this aspect of the invention, composition a) is prepared and applied by the coating technique described below, followed by curing. In the next step, composition b) is prepared and composition c) is gradually added. A mixture of compositions b) and c) is then applied to the glass coated with composition a) by the coating technique described below, followed by curing. In one embodiment, composition a) is applied, then a mixture of compositions b) and c) is applied, and a curing step is carried out.

[0065] In one embodiment of the above aspect, composition a) or b) comprises 50-90 wt% of one or more alkoxysilanes.In one embodiment of the above aspect, composition a) or b) comprises 65-75 wt% of one or more alkoxysilanes.

[0066] In one embodiment of the above aspect, composition a), b) or c), if present, independently comprises 1 to 30 weight percent of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides. In one embodiment of the above aspect, composition a), b) or c), if present, independently comprises 5 to 25 weight percent of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides.

[0067] In one embodiment of the aspects provided herein, the catalyst is present in an amount of 0.1 to 1 wt %. In one embodiment of the aspects provided herein, the catalyst is present in an amount of 0.1 to 0.5 wt %.

[0068] In one embodiment of the aspects provided herein, the amount of water present is greater than 0% by weight and within the ranges provided herein.

[0069] In one embodiment of the above aspect, composition a) is present at 20-70% by weight. In one embodiment of the above aspect, composition a) is present at 30-65% by weight. In one embodiment of the above aspect, composition a) is present at 40-65% by weight. In one embodiment of the above aspect, composition a) is present at 40-66% by weight. In one embodiment of the above aspect, composition a) is present at 40-50% by weight.

[0070] In one embodiment of the above aspect, composition b) is present at 5 to 40% by weight. In one embodiment of the above aspect, composition b) is present at 5 to 35% by weight. In one embodiment of the above aspect, composition b) is present at 10 to 35% by weight. In one embodiment of the above aspect, composition b) is present at 10 to 30% by weight. In one embodiment of the above aspect, composition b) is present at 10 to 25% by weight.

[0071] In one embodiment of the above aspect, composition c) is present at 0 to 50% by weight. In one embodiment of the above aspect, composition c) is present at 5 to 50% by weight. In one embodiment of the above aspect, composition c) is present at 10 to 50% by weight. In one embodiment of the above aspect, composition c) is present at 15 to 50% by weight. In one embodiment of the above aspect, composition c) is present at 20 to 50% by weight.

[0072] Any combination of the above amounts is encompassed by the present invention.

[0073] The alkoxysilanes used in the invention provided herein can generally be any alkoxysilane capable of reacting with one or more metal or metalloid oxides and / or metal or metalloid alkoxides, i.e., having a reactive group or capable of providing a reactive group upon reaction with water. In one embodiment, the one or more alkoxysilanes can be represented by the general formula R x Si(OR 1 ) 4-x may be selected from.

[0074] R is, but is not limited to, for example, C 1~18 Alkyl, C 1~18 Heteroalkyl, C 1~18 Alkoxy, C 2~18 Alkene, Phenyl, R 2 -(CH2) n - and R 2 -O-(CH2) n -, or any isomer or multivalent form thereof.

[0075] C 1~18 The alkyl group is, for example, a saturated straight chain or branched acyclic hydrocarbon having 1 to 18 carbon atoms, 1 to 15 carbon atoms, 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, 1 to 3 carbon atoms, 2 carbon atoms, or only 1 carbon atom. The alkyl group may be selected from the group consisting of, but not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, t-pentyl, neo-pentyl, i-pentyl, s-pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl, or isomers or polyvalent forms thereof. The alkyl group may be optionally substituted with further alkyl groups, hydrogen, halogen, and / or -CN, etc.

[0076] C 1~18 Heteroalkyl groups are defined as C as above, in which one or more carbon atoms are replaced by heteroatoms independently selected from the group consisting of oxygen, sulfur and / or silicon. 1~18 It is an alkyl group.

[0077] C 1~18 An alkoxy group is an alkyl group, as defined above, specifically linked to an oxygen. Representative alkoxy groups include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, and n-butoxy.

[0078] C 2~18 An alkene group is an unsaturated hydrocarbon having 2 to 18 carbon atoms and one or more carbon-carbon double bonds, such as, but not limited to, -CH=CH2, -CH=CH-CH3, -CH2-CH=CH2, -CH=CH-CH2-CH3, -CH=CH-CH=CH2, etc. The alkene group may be optionally substituted with further alkyl groups, hydrogen, halogen, and / or -CN, etc.

[0079] R in the above formula 2 is hydrogen, C 1~18 Alkyl, (C2H4O)-(R 3 ) m - or C 2~18 In one embodiment, R may be an alkene, or an isomer or multivalent form thereof. 2 may be (C2H4O)CH2-O-(CH2)3-.

[0080] R 3 is C 1~18 alkyl, or any isomer or polyvalent form thereof.

[0081] X may be an integer from 0 to 3, for example, x may be 1, 2 or 3. n may be an integer from 0 to 10, such as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. m may be an integer from 0 to 10, such as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0082] In a preferred embodiment, low chain polymer molecules are used to allow better penetration into the microcracks. In a further embodiment, a low chain polymer coating material can be introduced first to allow best penetration to the tips of the microcracks, and then a second coating can be introduced on top of the first coating to evenly fill the remaining crevices. By applying this technique, the greatest possible coverage of the reactive "partner", i.e., the coated compound having a terminal Si-OH bond, is obtained. In this regard, the "low chain polymer molecule" may have an alkyl group, heteroalkyl group, alkoxy group, or alkene group having less than 18 carbon atoms, such as less than 15 carbon atoms, less than 10 carbon atoms, less than 8 carbon atoms, less than 5 carbon atoms, or even less.

[0083] In one embodiment, the one or more alkoxysilanes are selected from glycidoxypropyltrimethoxysilanes, such as (1) β-glycidoxypropyltrimethoxysilane or (2) γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropylsilane, methoxyethylsilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, and triethylmethoxysilane. In one embodiment, the alkoxysilane is glycidoxypropyltrimethoxysilane. In a preferred embodiment, the alkoxysilane is γ-glycidoxypropyltrimethoxysilane. These chemicals are widely available and can be purchased from many chemical suppliers.

[0084] The one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides may generally be selected from any metal compound that can react with one or more alkoxysilanes.For example, the metal components of these compounds may be selected from, but are not limited to, boron, aluminum, gallium, indium, thallium, silicon, germanium, tin, lead, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, copper, silver, gold, palladium, platinum, zinc, cobalt, rhodium, iridium, selenium, tellurium, or polonium.In one embodiment, the one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides are selected from the oxides and / or alkoxides of aluminum, silicon, and / or titanium.In one embodiment, the metal is titanium and / or silicon. The alkyl portion of the alkoxy group may be selected from, but is not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, t-pentyl, neo-pentyl, i-pentyl, s-pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl, or isomers or polyvalent forms thereof. In a further embodiment, the metal alkoxide may be, but is not limited to, B(OCH3)3, B(OC2H5)3, B(OC3H7)3, Ti(OCH3)4, Ti(OC2H5)4, Ti(OC3H7)4, Ti(OC4H9)4, Zr(OC2H5)4, Zr(OC3H7)4, Zr(OC4H9)4, Al(OC2H5)3, Al(OC3H7)3, Al(OC4H9)3, Si(OCH3)4, Si(OC2H5)4, Si(OC3H7)4, CH3Si(CH3)3 or (CH3)2Si(OCH3)Cl, or any other metal instead of the metals outlined above. The alkyl group may be optionally substituted with a halogen, such as, for example, fluorine, chlorine, bromine, iodine. In one embodiment, the alkoxysilane is reacted with at least two different metal compounds selected from any of the metal and / or metalloid oxides and / or metal and / or metalloid alkoxides defined above. In one embodiment, one of the at least two different metal compounds is a silicon compound.

[0085] In one embodiment, the one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides are not oxides and / or alkoxides of cerium. In one embodiment, the one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides are not oxides and / or alkoxides of tin. In one embodiment, the one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides are not oxides and / or alkoxides of aluminum.

[0086] In one embodiment, the alkoxysilane is β-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and the one or more metal or semimetal alkoxides are selected from titanium alkoxides and / or silicon alkoxides. For example, the alkoxysilane may be γ-glycidoxypropyltrimethoxysilane, and the one or more metal alkoxides may be selected from, but are not limited to, B(OCH3)3, Ti(OC2H5)4, Ti(OC3H7)4, Si(OCH3)4, Si(OC2H5)4, CH3Si(CH3)3, or (CH3)2Si(OCH3)Cl, or any other metals as outlined above.

[0087] In one embodiment, the alkoxysilane is γ-glycidoxypropyltrimethoxysilane and the one or more metal alkoxides are B(OCH3)3, Ti(OC2H5)4, Ti(OC3H7)4, Si(OCH3)4, Si(OC2H5)4, CH3Si(CH3)3, or (CH3)2Si(OCH3)Cl.

[0088] In a further embodiment, the coating used is the product of hydrolytic polycondensation of γ-glycidoxypropyltrimethoxysilane with titanium alkoxide.

[0089] The coating provided can be made hydrophobic if each metal compound contains some alkyl bonds, rather than only alkoxy bonds. The alkyl bonds of these compounds are inert and remain as stable groups at the end with hydrophobic properties. Hydrophobicity can also be induced in the coating by including soluble or dispersible fluorine compounds in the precursor coating solution. Fluorine compounds commonly used in this field, such as fluorinated alkyl or alkoxy groups, can be used in the coating of the present invention, but are not limited thereto.

[0090] Exemplary coatings for use in accordance with the present invention may include, but are not limited to, the following:

[0091] [Table 1]

[0092] The coating is soluble in a suitable solvent depending on whether the coating has hydrophilic or hydrophobic properties. In one embodiment, the solvent is an organic solvent. In one embodiment, the solvent is a hydrophilic solvent. Non-limiting examples of solvents are alcohol or water, optionally enhanced by a surfactant. In one embodiment, the solvent may be ethanol, propanol, water or a mixture thereof, optionally including a surfactant. The amount of solvent is used to match the viscosity and / or concentration and / or surface tension of the coating. By controlling the viscosity and / or concentration and / or surface tension of the solution, the penetration to the tip of the surface defect can be controlled.

[0093] The viscosity of the coating can also be controlled by specifically selecting the (starting) components with the desired viscosity. In one embodiment, the penetration into cracks in the glass surface described above can be increased by reducing the viscosity of the coating or coating solution.

[0094] The coatings provided herein provide soluble organic-inorganic copolymer structures that deposit on glass surfaces as films that are transparent and non-brittle, yet substantially as hard and abrasion resistant as the substrate glass surface.

[0095] In addition to the above, a favorable effect regarding the absence of cracks forming in the glass can be expected by ensuring that water vapor (typically from humidity in ambient or compressed air) is not present anywhere in the atmosphere, from the process steps of melting, gob formation (or other exposure of molten glass to the atmosphere), hot forming (e.g., pressing, blowing, floating, updraw, downdraw, overflow melting, tube drawing, rod drawing), and finally through the application of the coating. By ensuring that water molecules are not present on the glass surface, the formation of microcracks can be limited. Without wishing to be bound by theory, it is believed that the presence of water vapor may promote crack propagation, since the hydroxyl groups required to fill the complete valence band of the silicon atom (four valences) require (OH) groups on the surface to complete the fourth valence. In the absence of water vapor, the valences cannot be filled, and theory suggests that a fairly large force is required for the crack to propagate. For example, even small amounts of water present in the atmosphere are believed to cause crack propagation, and the absence of water, or at least a very low concentration, may greatly limit crack propagation.

[0096] Crack propagation through the coating is prevented, inter alia, by the coating penetrating the crack all the way to the crack tip to produce maximum effect.

[0097] In one embodiment, the surface of the damaged silica-containing material is pretreated, with or without its edges. The pretreatment can improve the adhesion of the coating and / or reduce the depth and / or radius of the microcracks on the glass surface. The pretreatment can be performed with any suitable (chemical) material. For example, such pretreatment can be performed with hydrofluoric acid, with mechanical edge grinding, with flame polishing, with laser treatment, and / or with any other edge treatment technique, or by any other suitable method. By pretreating the silica-containing material, the coating can penetrate the surface of the microcracks in the silica-containing material more effectively and more completely, and further reduce the mechanical defects given, especially to the edges of the silica-containing material.

[0098] In one embodiment, the silica-containing (including but not limited to compounds) material, in the form of a porous material or powder, e.g., loose or compressed (compressed, prepreg, sintered, etc.), is partially or fully immersed into the coating throughout the pores or into the powder clusters. The immersion of the material or powder may be carried out for more than 1 second, more than 10 seconds, more than 1 minute, more than 1 hour, more than 1 day, or more than 1 week, or longer, to allow complete immersion of the voids between the pores, particles, or substrate parts. The immersed material may then be formed, cured, heated, further pressed, or sintered as described herein to prepare the final product. The powder or porous material may be formed into a prepreg material prior to infiltration or immersion.

[0099] In one embodiment, the silica-containing material, preferably glass, is heated to a transition temperature T prior to application of the coating in order to reduce either or both the depth or radius of microcracks in the glass surface. g The material is then heat treated to a suitable temperature below, near or above the transition temperature T g In another embodiment, the transition temperature T gSuitable temperatures below are at least 100K, 125K, 150K or higher. In one embodiment, shock cooling can be applied. Heat treatment with or without shock cooling can allow the coating to penetrate more effectively and more completely to the surface of microcracks in the glass substrate. Furthermore, this method can allow for homogenization or even dissolution of defects (e.g., particles) within the body of the glass substrate.

[0100] In one embodiment, any mechanical defects resulting from cutting or similar methods that result in uneven edges of the silica-containing material are pretreated with either chemical etching, fire polishing, prescribed edge grinding, or any other edge smoothing method, or any combination thereof, prior to applying the coating.

[0101] The coatings provided herein improve the mechanical strength of glass compared to uncoated glass products. This increase is controllable depending on the coating used and can provide a minimum of 50% increase in mechanical strength. In one embodiment, the strength is increased by more than 100%, more than 150%, more than 250%, more than 300%, more than 500%, more than 1000%, more than 1500%, more than 2000%, more than 5000%, or even more than 10000%. The glass strength is increased by more than 0.5 times, more than 1 times, more than 1.5 times, more than 2.5 times, more than 3 times, more than 5 times, more than 10 times, more than 15 times, more than 20 times, more than 50 times, or even more than 100 times compared to the original untreated glass substrate. This improvement is relative to the baseline mechanical strength of untreated glass after melting, forming, and cooling. The limit of the increase in mechanical strength may only be limited by safety-related concerns. As mechanical strength increases, the available energy released at the break point results in a more violent energy release and showering of smaller glass segments or particles. According to the present invention, the improvement of mechanical strength can be easily controlled with an accuracy of up to 100%. The change in mechanical strength can be measured by any method known to those skilled in the art, such as three-point or four-point glass probe, ring-on-ring probe, hydrostatic pressure with any fluid build-up pressure until the instrument breaks, increase in force per unit time (comparison of two different glass populations), or other methods. The effectiveness of the chemical bond can be demonstrated by quantitative Auger electron microscopy, electron probe microanalyzer (EPMA) techniques, or any other method known to those skilled in the art.

[0102] In one embodiment, the improvement in glass strength (and toughness) is 50-5000%, for example, 50-4500%, 50-4000%, 50-3500%, 50-3000%, or 50-2500%. In one embodiment, the improvement in glass strength is greater than 5000% or even greater than 10000%. The improvement in strength of silica-containing materials can be achieved by repairing newly manufactured or damaged silica-containing materials (new or used) with the coating composition of the present invention. Also, ductility can be increased and brittleness can be decreased.

[0103] The coated glass has a glass strength (and toughness) of at least 150 MPa. For example, the coated glass has a strength of at least 150 MPa, 200 MPa, at least 250 MPa, at least 500 MPa or more. In other embodiments, the glass strength may be at least 120 MPa, at least 100 MPa or at least 75 MPa. The strength parameters also apply to other silica-containing materials described herein.

[0104] The increase in glass strength along with the increase in ductility may allow the coated glass to withstand high temperature differences, such as cooling from ambient or high temperatures to cryogenic temperatures, or vice versa. For example, the coated glass can easily withstand temperature differences of more than 50K, 100K, 150K, 200K, or 250K when freezing the glass from ambient to very low temperatures, or when thawing glass held at temperatures below 0°C in a very short time. In an exemplary embodiment, a vial (e.g., a vial for a pharmaceutical vaccine) stored at -78°C (195K) or -196°C (77K) or -269°C (4K) and warmed to room temperature in a very short time will not break, as both the glass strength and the ductility of the glass surface are significantly increased by the application of the present invention.

[0105] The refractive index of the coating can be adjusted to a desired value by adjusting the relative concentrations of the metal components in the copolymer.

[0106] Glass coated with the coatings provided herein may have a haze of 4% or less after 300 cycles in the Bayer Abrasion Test defined by ASTM-F735.

[0107] The increased glass strength along with increased ductility may allow, or at least enable, the coated glass to withstand higher impact forces from solid objects impacting the glass at different angles and at more or less high speeds. In exemplary embodiments, photovoltaic glass panels, solar thermal glass panels or tubes, or window panes withstand larger hailstones or stones impacting these panels at higher speeds without breaking or other damage. In further exemplary embodiments, the coated glass withstands higher impacts caused by violent acts such as bullets, battering rams, or other impact devices impacting the coated glass.

[0108] The increase in glass strength along with the increase in ductility may allow container glass (including but not limited to glass bottles, glass jars, drinking glasses, or any other glass with a closed or open hollow volume) to withstand significantly higher pressures from inside the container or withstand significantly higher forces from impact. In an exemplary embodiment, a bottle (container) filled with a liquid containing carbon dioxide may be susceptible to high or excessive pressure, for example due to an increase in ambient temperature, and thus the glass bottle (container) may be manufactured with a smaller wall thickness to the same pressure as untreated glass or may withstand a much higher pressure. As in paragraph

[0056] above, without limiting the effect to a particular glass, for example, a container such as a bottle, jar, or drinking glass may withstand a drop onto the floor with no damage or at least with only minor damage, compared to a wine glass not coated with the subject coating, which breaks on normal impact. Also, reusable bottles (containers) may be coated with the coating of the present invention and thus may be used much longer in a deposit or reuse system before the bottle (container) needs to be melted again to form a new bottle (container). This extension in the deposit or reuse system can save energy and raw materials.

[0109] The presence of additional silicon in the coating may promote better bonding between the coating and the glass, lowering the refractive index to obtain a better fit to the substrate glass, and may have the added benefit of obtaining better adhesion of the coating to the glass surface. This is due to the fact that silicon alkoxides retain some alkoxy bonds, even under excess water, and these bonds react with the hydroxyl bonds of the glass surface during heat treatment. For example, Figure 2 is a schematic diagram of the chemical bonding of the coating on the glass surface, showing the covalent bonding of the coating to the glass (a) and the immobilization of sodium ions by boron coordination changes.

[0110] According to the present invention, one or more coatings may be applied to the glass substrate. When two or more coatings are applied, the additional coatings may have different properties and may provide different or enhanced functionality to the glass substrate. For example, different coatings may provide different strengths. In one embodiment, one coating layer may provide additional oxygen sites or other bridging divalent species, such as, but not limited to, sulfur, selenium, tellurium, polonium, copper, or ytterbium, to allow more covalent bonds for the second coating. The second or further coatings may provide additional protection against damage from, for example, dirt, weathering, and / or energy release at the breaking force, or may provide additional abrasion and / or chemical resistance. The second or further coatings may selectively form chemical bonds to ensure the best uniformity of bonds forming a coating at the level of angstroms or more per layer from the tip of the crack to the surface, further controlling the strength of the glass. In one embodiment, the abrasion resistance may be improved by the second or further coatings. Thus, the second or further coatings may provide: (1) protection against damage from fouling, weathering and / or energy release at the point of breakage; (2) improved abrasion resistance; (3) improved birefringence; (4) altered refractive index; (5) increased hardness; (6) protection from voltage-induced degradation of photovoltaic or semiconductor devices; (7) increased mechanical strength controlled to design strength within -50% / +100% accuracy; (8) fungicidal, antibacterial and / or antiviral properties; and / or (9) hydrophobic and / or oleophobic properties to repel water, oil, grease, etc.

[0111] Another important aspect concerns the application of the coating to the glass surface. For the coating to reach the tip of the crack, it is desirable that the most important restraining forces from oxygen, nitrogen or water molecules, or argon atoms (or other species contained in the atmosphere) do not prevent this. Therefore, a controlled atmosphere or vacuum, for example with industrial or special gases such as helium, hydrogen, neon, dry air, nitrogen, argon, oxygen, ozone, carbon dioxide, is advantageous to promote the penetration of the coating to the tip of the crack. In one embodiment, the controlled atmosphere is characterized by using helium, hydrogen, neon, oxygen and / or ozone. In one embodiment, the controlled atmosphere is characterized by the absence of oxygen. The vacuum may be an absolute pressure of 950 hPa or less, preferably less than 500 hPa, more preferably less than 100 hPa, even more preferably less than 10 hPa or less. In one embodiment, the vacuum may be less than 1 hPa, or, if economically justified, more preferably less than 0.1 Pa, or less than 10 -6 Pa, or even less than 10 −9 Pa. The controlled atmosphere may be applied to the application space and / or the space from the glass outlet to the hot forming apparatus.

[0112] Additionally or alternatively, heating the chemical solution just below the boiling point of the solvent and / or heating the glass substrate to a high enough temperature opens up cracks and reduces the viscosity, increasing the penetration of the coating to allow for better penetration and therefore repair of the surface defects. Additionally or alternatively, heating the chemical solution above the boiling point converts the chemical solution to a gaseous state or even drives the chemical solution into a plasma state and / or heating the glass substrate to a high enough temperature opens up cracks and further reduces the viscosity, increasing the penetration of the coating to allow for better penetration and therefore repair of the surface defects.

[0113] The coating can be applied by various methods known to those skilled in the art. For example, the coating may be applied from either a liquid (including gel), gas, or plasma state. The coating could potentially be applied from a solid state, possibly in the form of a nano-powder. The coating can be applied by any suitable application technique used in the art. In one embodiment, the coating can be applied by, but not limited to, dip coating, spray coating, roller coating, vapor deposition (CVD, PECVD, etc.), atomization, plasma external deposition, chemical vapor deposition, and / or plasma induced vapor deposition (PICVD, etc.). The coating can be added to a suitable solvent, such as H2O, which is used as a starting material for certain materials, such as concrete or cement, or any other material that utilizes a solvent or solvent mixture. This allows for a complete and uniform distribution of the coating within the material.

[0114] For example, when dip coating is applied, the pulling speed is in the range of 20 mm / min to 15,000 mm / min (250 mm / s), for example, 50 mm / min to 10,000 mm / min or 100 mm / min to 1,000 mm / min. A faster pulling speed typically produces a thicker coating film, while a pulling speed that is too slow may polymerize the coating on the glass substrate surface during pulling. Thus, the ideal pulling speed depends on various factors such as viscosity, reaction time of the compound, etc. Typical thicknesses for the dip coating process are 1 to 10 microns, for example, 3 to 7 microns. The thickness may be (substantially) less than 1 micron, with the lowest possible coating thickness being desired.

[0115] In one embodiment, the above compositions a) and b) can then be applied by any of the above methods. In one embodiment, the compositions a) and b) can be applied by spray coating or spraying, either with one spray nozzle or two or more different spray nozzles. In this embodiment, the coatings can be applied simultaneously or in subsequent coating steps. If one spray nozzle is applied, the compounds need to be premixed before the nozzle inlet. If two or more spray nozzles are applied, the compounds are premixed before the nozzle inlet or the individual compositions a), b) and / or c) are injected through separate nozzles so that the separate sprays merge before or on the glass substrate surface. It is equally applicable to apply a subsequent coating step through separate nozzles for each composition a), b) and / or c). If the nozzle sprays the compositions separately, any premixed combination of (i) a) and b), (ii) a) and c), or (iii) b) and c) can be fed to the nozzle inlet in addition to the individual compositions a), b) or c) through any nozzle. Any nozzle may have a particular shape corresponding to optimal jetting. In one embodiment, atomization may be achieved using pressure without the use of any carrier species. In another embodiment, atomization may be achieved using compressed air or a pressurized gas or pressurized gas mixture, for example, but not limited to, an inert gas such as nitrogen. Other atomization techniques are also possible, such as, for example, mechanical or other trimwork or fixtures, electromechanical devices, or plasma.

[0116] The application of the coating may be aided by the use of a catalyst, such as, but not limited to, water, preferably deionized water, more preferably distilled water, and even more preferably multi-distilled water, such as so-called "bi-distilled water", for example, to increase the reaction rate of the coating with hydroxyl groups in the cracks on the glass substrate. Such a catalyst may be the presence of a particular species, or may be a particular process parameter, such as, for example, temperature, pressure, plasma, etc.

[0117] It is also included herein that any unused or residual coating that is not required for the chemical reaction to form the covalent bonds necessary for the reaction to repair some or all of the microcracks is removed (i.e., recovered) after the coating is applied, for example, by immersing the coated glass in a suitable solvent such as water and / or alcohol or rinsing the coated glass with a suitable solvent such as water and / or alcohol, so that enough coating remains in the former cracks for effective bonding and repair. Suitable solvents can be, but are not limited to, water, ethanol, isopropanol, or mixtures thereof. In a preferred embodiment, the solvent used is ethanol. Thus, no coating is left behind except for the amount required for the reaction to repair the microcracks, resulting in a saving of coating and allowing for intact glass that exhibits essentially the same visual properties as the uncoated one, while still providing the same strength increase.

[0118] After application, the coating is dried to remove the solvent and excess water, and then heated to promote the continuous condensation or precipitation polymerization of the coating, which hardens into a dense glassy film. The heat treatment is carried out independently of the coating method described above. The heat treatment may be carried out at a suitable temperature for a suitable time. For example, the coated glass may be heat treated at 100-500°C, such as, but not limited to, 100-400°C, 100-300°C, or 100-200°C for 30 minutes, 60 minutes, 2 hours, or more than 2 hours. Process temperatures higher than 150°C and even higher than 200°C may result in shorter processing and / or curing times, which are generally preferred. The drying step may be assisted by the use of a vacuum at an absolute pressure of 950hPa, preferably less than 500hPa, more preferably less than 100hPa, and even more preferably less than 10hPa or less.

[0119] After application of the coating, the coating is cured. In one embodiment, curing of the applied coating is performed at a temperature above 30°C, such as above 50°C, above 80°C, above 100°C, above 120°C, above 130°C, above 150°C, above 200°C, or even above 300°C. The curing temperature is applied for a time sufficient to achieve curing. For example, curing may be performed for a period of time lasting at least milliseconds, such as at least 100 ms, 200 ms or more, at least seconds, such as at least 10 seconds, 30 seconds, 45 seconds or more, or at least minutes, such as at least 1 minute, 2 minutes, 3 minutes, 5 minutes, 10 minutes, 20 minutes, 30 minutes or more.

[0120] In another embodiment, the curing is caused by exposing the coated silica-containing material, preferably glass, to specific waves of appropriate frequency and / or wavelength. Non-limiting examples of suitable wavelength ranges / radiation are ultrasound, such as subsonic, sonic or supersonic ranges, visible range, ultraviolet range, extreme ultraviolet range, infrared range, microwave range, or any other different ranges that respond to specific correlated wavelengths (e.g., individual characteristic frequencies of molecular reactants) that cause molecules to react.

[0121] In another embodiment, the coated silica-containing material is exposed to tempering before or after coating.

[0122] In one embodiment of the method of the present invention, composition a) and composition b), or a mixture of composition a) and composition b) with composition c), may be applied sequentially to a glass surface and cured sequentially.

[0123] In some hot forming processes, it is possible to generate a controlled atmosphere or vacuum with no or very low water vapor content and an absolute pressure of 950 hPa or less, for example conditioned air with a dew point below -20°C (253 K), more preferably below -50°C (223 K), more preferably below -78.5°C (194.7 K), and if economically justified, more preferably below -195.8°C (77.35 K), more preferably below -246°C (27 K), more preferably below -269°C (4 K), from the outlet of the molten glass throughout the entire forming apparatus or even the annealing furnace, thereby preventing as much as possible water from reacting with the glass surface and thus improving the outcome of the chemicals that do react with the glass surface instead. Furthermore, the absence or significant reduction of water vapor presence can prevent crack propagation during the crack formation process, thus resulting in smaller crack depths and resulting volumes, and less coating material may be required as the "penetration resistance" of the coating into the voids resulting from the cracks is greatly reduced.

[0124] In the present invention, any of the process steps from batch storage, batch mixing, batch filling, batch preheating if applicable, melting, refining, gob formation, hot forming, etc. to application of the coating, or the entire process from batch storage to application of the coating, can optionally be performed in all or part in a controlled atmosphere (as described above) having very low water vapor pressure (water vapor partial pressure).

[0125] The use of coatings benefits all glass applications and products. For example, the coatings can be applied to, but are not limited to, beverages, spirits, food, pharmaceuticals; flat glass (e.g., automotive, architectural, photovoltaic, solar thermal), electronics (e.g., computer displays, laptop displays, smartphones, wafer-level packaging); mirrors or mirror substrates, aerospace applications, astronomy applications, ophthalmic devices, optical devices, optical or other communication fibers, woven reinforcement fibers, insulating fibers, tubes and / or rod glass (e.g., for pharmaceutical packaging, solar thermal, photovoltaic, lighting tubes), mask blanks (for microlithography), glass, ceramic, glass-ceramic, or composite films (e.g., for batteries, fuel cells), pressed glass for high-precision reflectors, LED or OLED applications, glass powder as protection against leaching, or containers for waste vitrification glass (e.g., ash vitrification, nuclear waste vitrification).

[0126] The invention is not limited to a particular type of glass, but can be applied to any glass and for any purpose. Suitable glass types include, but are not limited to, soda lime, borosilicate, aluminosilicate, opal glass, sapphire, calcium fluoride, chalcogenite glass, silica (pure or doped), glass ceramic, ceramic, pure or impregnated quartz, glass crystal or quartz crystal, any type of glass or ceramic or glass ceramic and composites of at least one other material, etc. For example, the coating can be applied to all glasses that melt at high temperatures, at least 450° C., at temperatures above 1100° C., or at temperatures above 1400° C. In general, there is no restriction regarding the upper temperature limit. That is, the coating can be applied to molten or formed glass when a suitable temperature for applying the coating is reached, i.e., without the coating decomposing. Thus, the coating can be applied to any glass, e.g., at temperatures above the transition temperature (T g)±300° C. or any glass produced by applying a sol-gel process at temperatures below 1200° C., below 1000° C., below 850° C., below 600° C., below 450° C., below 300° C., or below 150° C., such coatings being applied when the appropriate temperature is reached. In one embodiment, the coating may be applied at a temperature below 450° C.

[0127] In one embodiment, the coating of the present invention is not applied to a polymeric substrate. In one embodiment, the coating of the present invention is not applied to a polycarbonate. In one embodiment, the coating of the present invention is not applied to an acrylate.

[0128] The present invention is suitable for any possible preparation method, including but not limited to any hot forming technique, particularly but not limited to press blow (e.g., individual section machines, NNPB (narrow neck pressure blow)), blown glass, float glass, rolled flat glass, tube forming (e.g., tube drawing by Danner process, Vello process, etc.), pressing, updraw, downdraw, overflow melting, pressing, mouth blow, casting, carousel type machines, tube to container conversion, and temperature cooling or heating devices to control glass temperature and glass temperature distribution.

[0129] In one embodiment, prior to application of the coating, the molten glass is drawn immediately after the hot forming process to produce thinner glass and / or reduce glass defects.

[0130] In a further aspect, the invention relates to a glass or silica-containing product having a coating as described herein.

[0131] The coating on the glass product can have a thickness suitable for each purpose. For example, the coating can have a thickness of less than 10 microns. In an embodiment, the coating can have a thickness of less than 5 microns, such as less than 3 microns or less than 2 microns, or even less than 1 micron. Even thinner coatings can be applied. The coating can be controlled in several ways, such as the viscosity and / or concentration and / or surface tension of the coating solution, the time the coating is applied to the glass, the temperature, controlling the atmosphere, ambient pressure or absolute pressure vacuum as defined above. In general, a lower viscosity contributes to the effectiveness of the coating liquid penetrating into the microcracks, resulting in more reactive partners and therefore more covalent bonds being formed.

[0132] It is generally preferred to make the coating as thin as possible.

[0133] In a further aspect, the invention relates to a coating prepared by the methods provided herein.

[0134] In yet another aspect, the present invention provides a method for producing a pharmaceutical composition comprising: a) 50 to 85% by weight of a compound of the general formula R in the presence of 10% by weight or less of water, 30% by weight or less of alcohol and 1% by weight or less of a catalyst. x Si(OR1) 4-x (wherein R is an organic radical; R 1 is hydrogen and C 1~18 and one or more alkoxysilanes of the formula (I) (independently selected from alkyl, aryl, aryls, arylalkyl, aryls ... b) a composition comprising 20-100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 80% by weight or less of an alcohol, 20% by weight or less of water, and 1% by weight or less of a catalyst; and c) A composition comprising 50% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. A coating comprising a mixture of The weight percentages of a), b), c) and mixtures thereof each relate to the coating, which total 100% by weight.

[0135] In this aspect of the invention, the above information and specific embodiments also apply.

[0136] In yet another aspect, the present invention relates to a method of improving the (mechanical) strength of glass, comprising applying to the glass one or more coatings provided herein, the one or more coatings being applied as described above. The method may further comprise the step of preparing one or more coatings provided herein.

[0137] All the above embodiments can be combined in any possible way. The embodiments specifically relating to glass also apply to the other silica-containing materials described herein. EXAMPLES

[0138] In order to more particularly describe the present invention and to aid in the understanding of the present specification, the following non-limiting examples are provided to fully illustrate the scope of the present specification and should not be construed as specifically limiting the scope thereof.

[0139] Example I A clear, hard, non-brittle coating solution is prepared as follows. 100g Glycidoxypropyltrimethoxysilane [ka] is mixed with 100 grams of ethyl alcohol, C2H5OH. 8 grams of water and 0.3 grams of nitric acid, HNO3, are added to this mixture and stirred for 10 minutes. This procedure hydrolyzes the methoxy groups of the compound, converting them to hydroxy groups. After this, 40 grams of titanium ethoxide, Ti(OC2H5)4, is also added and stirred for another 10 minutes to react with the hydroxyl bonds, chemically bonding the titanium compound to the molecular structure of the glycidoxypropylsilane through oxygen. Once the titanium and organic components are chemically bonded by this procedure, additional water can be added without fear of causing separate condensation or precipitation. This water causes further polymerization of the system into long chains and provides hardness to the coating by removing excess organics from the structure.

[0140] A number of 10 cm x 10 cm, 2 mm thick float glass samples are coated by immersion in this solution and heat treated at 130 °C for 30 minutes. Their abrasion resistance was tested for 300 cycles by the ASTM F-735 Bayer abrasion test method and found to be about 1.0, which is substantially similar to the abrasion resistance of uncoated glass surfaces. The strength of these samples was also measured by the conventional ring-over-ring method and the "cone crack load" method at Pennsylvania State University. The results are shown in Figure 3. The uncoated glass showed a typical bell-shaped strength distribution ranging from 50 to 150 MPa with a mean value of about 100 MPa. On the other hand, testing of the coated samples gave a strength distribution ranging from about 200 to 350 MPa, with an average strength of about 250 MPa, a 2.5-fold increase in strength. Figure 4 is a comparison of the mean and range of the average cone crack loads of the glass samples. It is found that the "tin side" of the glass (i.e. the bottom of the float glass in contact with the tin bath in which the glass floats) has a significantly lower crack resistance than the "air side" (i.e. the top of the float glass) due to microscopic defects imparted by the above and other phenomena. More important are defects in the steel rollers that support the surface over which the glass is pulled after it leaves the tin bath. These rollers can cause scratches on the bottom glass surface. Some of the defects in the steel rollers can be caused by glass chips during the cutting process.

[0141] Example II An abrasion-resistant non-brittle coating solution is prepared similarly to Example I, except that titanium isopropoxide Ti(OC3H7)4 is used instead of titanium ethoxide. The abrasion resistance and strength results are nearly identical.

[0142] Example III A number of coating solutions were prepared similar to Example I, except that zirconium alkoxide Zr(OC3H7)4 and aluminum alkoxide Al(OC4H9)3 were used instead of titanium ethoxide Ti(OC2H5)4.

[0143] Example IV 100 grams of glycidoxypropyltrimethoxysilane is mixed with 100 grams of ethyl alcohol C2H5OH. To this mixture, 8 grams of water and 0.3 grams of nitric acid are added and stirred for 10 minutes. Then, 40 grams of titanium isopropoxide Ti(OC3H7)4 and 5 grams of silicon ethoxide Si(OC2H5)4 are also added and stirred for another 10 minutes to polymerize them with glycidoxypropyltrimethoxysilane. After this is done, 150 grams of water and 30 grams of ethanol are added to further polymerize the structure to larger molecular size and remove most of the organic end bonds from the structure.

[0144] This solution was also applied to glass samples and tested for strength and abrasion resistance, with similar results as shown in Example I.

[0145] Example V A coating solution was prepared similar to that in Example IV, except that the silicon was provided from 3 grams of silicon methoxide, Si(OCH3)4. The results were similar to those shown in Example IV.

[0146] To investigate the effect of the coating on the strength of the glass as a function of the thickness of the glass, solutions were prepared as in Example IV and coated onto float glass samples of various thicknesses. As the glass became thinner, the effectiveness of the coating increased. The coating increased the average strength of the glass from 130 MPa to about 250 MPa when the glass thickness was 3 mm, but increased to over 300 MPa when the glass thickness was 2 mm.

[0147] Example VI A coating solution is prepared as in Example IV, except that 3 grams of silicon methoxide Si(OCH) is used instead of silicon ethoxide Si(OCH) The results are similar to those shown in Example IV.

[0148] Example VII A coating solution is prepared similar to Example IV, except that 4 grams of methyltrimethoxysilane, CH3Si(OCH3)3, is added with the titanium isopropoxide instead of silicon methoxide. The resulting coating on glass not only strengthens the glass as well, but also renders it hydrophobic, providing additional properties and protection against water-related contamination and chemical effects.

[0149] Example VIII A coating solution is prepared similarly to Example IV, except that 2 grams of dimethylmethoxychlorosilane (CH3)2Si(OCH3)Cl is added together with titanium isopropoxide Ti(OC3H7)4 instead of silicon ethoxide. The resulting coating not only strengthened the glass, but was also hydrophobic.

[0150] Example IX A coating solution is prepared as in Example IV. Hydrophobicity is introduced by adding 2 grams of a commercially available fluorine compound into the solution. The strength increase results are similar to those of Examples I and IV, except that the coating has the additional properties of being hydrophobic and oleophobic (oleophobic).

[0151] Example X Tables 1 and 2 below provide further experimental evidence showing that the use of the coatings provided herein (all coated examples are within the scope of the coatings of the present invention) results in improved glass strength.

[0152] [Table 2]

[0153] [Table 3]

[0154] Example XI Figures 5a and 5b show examples of glass strengthening according to the invention. The uncoated sample (Figure 5a) shows a relatively moderate fracture pattern, evidence of a relatively low energy required for fracture. Here, a low force of about 79 MPa (about 11,600 psi) produced a fracture pattern. In contrast, the coated sample (Figure 5b) shows a relatively pronounced fracture pattern, evidence of a relatively high impact required for fracture and thus improved mechanical strength of the glass. Here, a higher force of about 364 MPa (about 53,000 psi) was required. The thickness of the surface coating was about 2.4 microns.

[0155] Example XII Figure 6 is a (sodium) dealkalization analysis of coated and uncoated glass, where the coating takes the terminal silica hydroxyl bond -Si-OH and after reaction bridges the oxygen with boron -OBO- instead of -O-Si-O- for example. The graph shows the cumulative sodium leaching from a 4.5" x 4.5" clear float glass sample immersed in 250cc H2O at 60°C (140°F). As can be seen from the graph, essentially no sodium leaches from the modified (coated) surface in contrast to the uncoated glass.

[0156] Example XIII Glass surfaces mechanically damaged by Vickers indentation using 10-20N cause severe surface damage to the glass (Figure 8 shows a soda-lime float glass probe that was intentionally mechanically damaged by Vickers indentation under different lighting conditions using a microscope). The coating solution of the present invention is then applied to the glass surface. Upon coating, hardening occurs in less than 60 minutes at temperatures above 30 °C. Figure 9 shows soda-lime and borosilicate glasses with Vickers indentation without coating on the left and soda-lime glasses with coating after Vickers indentation on the right, as well as the average value of the destructive test results. Figure 10 shows a detailed analysis of the surface structure of the Vickers indentation. The top view shows the morphology of the Vickers indentation on a computer-animated digital 3-D image from a digital microscope. The vertical plane on the left of the center means the analyzed plane where the indentation angle was analyzed, as shown at the bottom (here the vertical and horizontal scales are different). The V angle of the Vickers indentation is 148.26°, and the depth of the Vickers indentation is 11.67 μm. The image on the right side of the center is the same as the image on the bottom right of Figure 8.

[0157] As can be seen in Figure 9, the previous damage is not visible to the naked eye, and even under a microscope the previous damage is barely visible. Furthermore, the mechanical strength of the glass returns to the level of the original value of the undamaged glass, less than 10% lower than the original undamaged uncoated glass, and in some cases even returns to a higher value compared to the original undamaged glass. FIG. 11 outlines detailed values ​​of the breakage tests for (1) uncoated glass without mechanically induced defects, (2) uncoated glass with mechanically induced defects (partially treated at different temperatures), and (3) glass samples with mechanically induced defects that were coated after the application of defects (Coating Solution 1: Glycidoxypropyltrimethoxysilane, EtOH, HO, Ti(OCH)4; Coating Solution 2: Glycidoxypropyltrimethoxysilane, EtOH, Si(OCH), HO, Ti(OCH)4; Coating Solution 3: Glycidoxypropyltrimethoxysilane, EtOH, B(OCH), HO, Ti(OCH)4; all in amounts disclosed herein) and exposed to different temperatures.

[0158] As seen in Figure 11, the process of repairing mechanically induced surface defects was as follows: (1) An undamaged set of samples was tested for mechanical failure. (2) A set of samples was pre-damaged with Vickers indentation but not coated. They were then either kept at room temperature or heat treated at 120°C, 135°C or 150°C for 30 minutes before being subjected to mechanical failure testing. (3) All other samples were first pre-damaged with Vickers indentation and then coated with different solutions (formulas) before being subjected to mechanical failure testing. Attached Tables 1-3 show the general formulations of solutions (formulas) 1, 2 and 3 used in the testing. After mixing any of solutions 1-3, the samples were exposed to a curing temperature of 120, 135 or 150°C as outlined. For solutions 2 and 3 and 135°C, the solutions were applied to the glass substrate 2 hours after mixing the solutions.

Claims

1. 1. A method for preparing a coating for improving glass strength and fracture toughness of glass, said method comprising: a) 50 to 85% by weight of a compound of the general formula R in the presence of up to 10% by weight of water, up to 30% by weight of an alcohol and up to 1% by weight of a catalyst ｘ Si(OR １ ) ４－ｘ (wherein R is an organic radical, R １ is hydrogen and C １～１８ a composition comprising one or more alkoxysilanes of the formula (I), independently selected from alkyl, alkyls, or isomers or polyvalent forms thereof, and x is an integer from 0 to 3, and 35% by weight or less of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, wherein the reaction is carried out until no free water remains in solution for the next step, the alkoxysilanes being partially hydrolyzed, and the one or more metal or metalloid alkoxides being selected from alkoxides of boron, aluminum, gallium, indium, thallium, germanium, tin, lead, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, copper, silver, gold, palladium, platinum, zinc, cobalt, rhodium, iridium, selenium, tellurium, and polonium; b) a composition comprising 20 to 100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, up to 80% by weight of an alcohol, up to 20% by weight of water, and up to 1% by weight of a catalyst; and c) A composition comprising 50% by weight or less of one or more metal or semi-metal oxides and / or one or more metal or semi-metal alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. mixing the A method in which composition a), composition b), and composition c) are prepared sequentially in any order, and composition a), composition b), and composition c) are used in proportions of 20 to 70% by weight of composition a), 5 to 40% by weight of composition b), and 10 to 50% by weight of composition c), and the weight proportions of composition a), composition b), and composition c) respectively total 100% by weight.

2. A method for preparing a coating for improving glass strength and fracture toughness, comprising mixing the following compositions a), b) and c): a) reacting 5 to 95% by weight of a compound of the general formula R x Si(OR 1 ) 4-x (where R is an organic radical and R 1 is a group consisting of hydrogen and C 1-18 alkyl groups) in the presence of up to 20% by weight of water, up to 95% by weight of alcohol and up to 1% by weight of a catalyst; and up to 40 wt. % of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, wherein the one or more metal or metalloid alkoxides are selected from alkoxides of boron, aluminum, gallium, indium, thallium, germanium, tin, lead, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, copper, silver, gold, palladium, platinum, zinc, cobalt, rhodium, iridium, selenium, tellurium, and polonium. b) a composition comprising 20 to 100% by weight of one or more metal or metalloid oxides and / or one or more metal or metalloid alkoxides, up to 80% by weight of an alcohol, up to 20% by weight of water, and up to 1% by weight of a catalyst; and c) A composition comprising 50% by weight or less of one or more metal or semi-metal oxides and / or one or more metal or semi-metal alkoxides, 100% by weight or less of water, and 100% by weight or less of alcohol. The method comprises: preparing compositions a), b), and c) sequentially in any order; using compositions a), b), and c) in proportions of 20 to 70% by weight of composition a), 5 to 40% by weight of composition b), and 0 to 50% by weight of composition c); the weight proportions of compositions a), b), and c) respectively totaling 100% by weight; and applying compositions a) and b), or a mixture of compositions a), b), and c), sequentially to a glass surface, and curing the mixture sequentially.

3. 3. The method of claim 1 or 2, wherein the catalyst is nitric acid, aqua regia, hydrofluoric acid, or a combination thereof.

4. (a) the one or more alkoxysilanes are selected from β-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropylsilane, methoxyethylsilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, and triethylmethoxysilane; (b) the one or more metal or metalloid oxides are selected from oxides of boron, aluminum, gallium, indium, thallium, silicon, germanium, tin, lead, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, copper, silver, gold, palladium, platinum, zinc, cobalt, rhodium, iridium, selenium, tellurium, and polonium; and / or (c) The method of claim 1 or 2, wherein the one or more alkoxysilanes are β-glycidoxypropyltrimethoxysilane or γ-glycidoxypropyltrimethoxysilane, and the one or more metal or metalloid alkoxides are selected from boron alkoxides, titanium alkoxides, and silicon alkoxides, or mixtures thereof.

5. A coating prepared by the method of claim 1 or 2.

6. 10. Use of a coating prepared by the method of claim 1 or 2 for improving glass strength and fracture toughness of glass, wherein the glass strength and fracture toughness are improved by repairing cracks in the surface of the glass, and the coated glass is heat treated at 100°C to 300°C.

7. 3. Use of a coating prepared by the method of claim 1 or 2 to repair damaged silica-containing materials, optionally wherein said silica-containing materials include glass, ceramic, glass-ceramic, quartz, cement, concrete and any other material containing silica, or wherein said damage is caused by physical and / or chemical impact.

8. one or more further coatings are applied to provide abrasion resistance, chemical resistance, birefringence, refractive index modification, increased hardness, protection from voltage-induced degradation of the photovoltaic or semiconductor device, controlled increase in mechanical strength, improved hydrophobicity to provide water repellency, improved oil repellency, protection against damage from fouling, weathering and / or energy release at the point of breakage, fungicidal, antibacterial and / or antiviral properties; and / or the one or more coatings are applied by dip-coating, spray-coating, vapor deposition, atomization, plasma-external vapor deposition, chemical vapor deposition, plasma-induced vapor deposition, penetration, immersion, suspension and / or plasma-enhanced vapor deposition; and / or 7. The use according to claim 6, wherein the one or more coatings are applied in a controlled atmosphere, at sub- or super-atmospheric pressure and / or at temperatures above or below atmospheric temperature. (a) the controlled atmosphere comprises conditioned air having a dew point of less than -20°C (253K), -50°C (223K) or less, -78.5°C (194.7K) or less, -195.8°C (77.35K) or less, 27K or less, or 4K; (b) the controlled atmosphere comprises an industrial or specialty gas; and / or (c) The pressure is 950 hPa, less than 500 hPa, less than 100 hPa, less than 10 hPa, less than 1 hPa, less than 0.1 Pa, less than 10 －６ Pa or even less than 10 －９ 9. The use according to claim 8, wherein the pressure is less than 100 Pa.

10. Any unused coating is removed from the glass surface or silica-containing material, and / or 7. The use according to claim 6, wherein the unused coating is removed by immersing the coated glass or coated silica-containing material in a solvent or by rinsing the coated glass or coated silica-containing material with a solvent.

11. the improvement in glass strength is between 50 and 5000%, greater than 5000%, or greater than 10000%, and / or 7. The use according to claim 6, wherein devitrification is avoided.

12. Prior to applying said coating, the glass surface, optionally including the edges, is pretreated with hydrofluoric acid, mechanical edge grinding, flame polishing, laser treatment and / or any other edge treatment technique; and / or Before applying the coating, the glass is heated to a transition temperature (T ｇ 7. The method of claim 6, wherein the substrate is exposed to a temperature at least 300 K lower than that of the substrate. (a) applying a temperature of at least 30°C to the coated glass or coated silica-containing material for curing; (b) exposing the coated glass or coated silica-containing material to waves of suitable frequencies and / or wavelengths, including subsonic, sonic, supersonic, infrared, visible, ultraviolet, extreme ultraviolet, and / or wavelengths below the extreme ultraviolet range, and / or any other suitable frequencies and / or wavelengths that cause the desired reaction between the reactive partners depending on their physical properties, any frequency that allows the coating on the glass substrate to harden; and / or (c) The use according to claim 6, wherein the coated glass or coated silica-containing material is subjected to tempering before or after coating.

14. 7. Use according to claim 6, wherein the glass in the molten state is drawn immediately after the thermoforming process to produce thinner glass, before the application of the coating.

15. 7. The use of claim 6, wherein the silica-containing material is in the form of a porous material or powder and is partially or totally impregnated with the coating throughout the pores or within the porous material or powder clusters within a prepreg, whether pre-pressed or exposed to temperatures substantially above room temperature prior to infiltration or impregnation.

16. 7. A glass product or product made from a silica-containing material prepared by the use of claim 6.

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