Background of the Invention In the formulation of painting and coating materials, binder systems play a crucial role in determining the performance of the particular painting or coating material. For example, it is important that binder systems exhibit strong adhesion to substrates, bind together with other elements in the painting and coating system, and present good physical, chemical and mechanical properties such as resistance to abrasion, hostile chemicals and the environment. Therefore, those skilled in the art of binder systems are constantly striving for higher performance and novel products to meet the needs of various applications.

A variety of both organic and inorganic materials have been conventionally used in binder systems for painting and coating materials. For example, organic materials such as alkyds, urethanes, epoxies, and acrylic resins, are widely used in coating material binder systems. Additionally, inorganic materials such as alkali metal silicates, silica sols, and silicone resins have also been used for this purpose.

Conventional binder materials for coating and painting formulations are often solvent-based organic chemicals. One of the serious problems associated with these organic-based binders, however, is that these binders deteriorate over time when exposed to ultraviolet radiation and high temperature

environments. Furthermore, these binders tend to age over time when subjected to oxidation conditions.

Another disadvantage of solvent-based organic binders is the release of volatile organic compound (VOC) into the environment. VOC has been shown to have a detrimental effect on the earth's ozone layer. As a result, there is a trend to develop water-based binder systems for painting and coating applications.

Nevertheless, conventional water-based binders are still subject to deterioration when exposed to ultraviolet radiation, have low bond strengths to substrates and lack sufficient abrasion resistance.

Summary of the Invention The present invention provides an inorganic- organic hybrid binder system which can be used in various types of applications including painting and coating applications. The binder system exhibits strong adhesion to substrates and to the other elements in the paint or coating. In addition, the binder system has excellent abrasion resistance and possesses other good physical, chemical and mechanical properties. The inorganic-organic binder system of the invention is not subject to deterioration over time when exposed to ultraviolet radiation and high temperature environments. The use of the inorganic- organic binder system of the invention also does not produce VOC and is therefore environmentally friendly Furthermore, the hybrid inorganic-organic binder system can be used in the formulation of painting and coating materials having a variety of pigments, additives and/or fillers.

The present invention includes a binder composition comprising a quaternary system of an alkali metal silicate, a waterborne acrylic resin, an alkali metal methyl siliconate, and an organofunctional silane. The quaternary system is presented in an

aqueous system to provide a binder composition that can be used as a painting or coating material. Preferably, the amount of water used in the binder composition is between about 50% and about 70% by weight.

For the quaternary system (or active chemicals) in the binder composition, the alkali metal silicate is typically selected from lithium polysilicates, potassium silicates, sodium silicates, and mixtures thereof. Preferably, the ratio of SiO2 to M2O, where M is alkali metal, in the alkali metal silicate is between 2:1 and 10:1. The waterborne acrylic resin or acrylic emulsion used in the quaternary system is preferably an acrylic polymer or acrylic copolymer. The alkali metal methyl siliconate is preferably selected from potassium methyl siliconates, sodium methyl siliconates, and mixtures thereof. Additionally, the organofunctional silane in the quaternary system is a monomer, dimer or trimer, or a corresponding silanol and siloxane. In the quaternary system, the amount of alkali metal silicate is between about 50% and about 70% by weight, the amount of waterborne acrylic resin is between about 3% and about 10% by weight, the amount of alkali metal siliconate is between about 5% and about 10% by weight, and the amount of organofunctional silane is between about 2% and about 10% by weight. The binder composition is prepared by blending a quaternary system of an alkali metal silicate, a waterborne acrylic resin, an alkali metal methyl siliconate, and an organofunctional silane.

The present invention further includes a painted or coated substrate. The painted or coated substrate comprises a substrate, and a hardened painting or coating composition bonded to at least a portion of a surface of the substrate. The painting or coating composition comprises the reaction product of an alkali metal silicate, a waterborne acrylic resin,

an alkali metal methyl siliconate, and an organofunctional silane. The substrate can be a metal, ceramic, wood, stone, masonry, cementitious, or bituminous substrate. In addition, the hardened painting or coating composition can include at least one filler distributed throughout the reaction product of the alkali metal silicate, the waterborne acrylic resin, the alkali metal methyl siliconate, and the organofunctional silane.

The method of producing the painted or coated surface of the invention comprises applying a painting or coating composition to at least a portion of a surface of a substrate. The painting or coating composition comprises a binder capable of being polymerized and crosslinked and comprising a quaternary system of an alkali metal silicate, a waterborne acrylic resin, an alkali metal methyl siliconate, and an organofunctional silane. The binder in the painting or coating composition is then allowed to polymerize and crosslink to produce the painted or coated surface.

The binder can further include water and can be mixed with at least one filler or additive prior to allowing the binder to polymerize and crosslink.

These and other features and advantages of the present invention will become more readily apparent to those skilled in the art upon consideration of the following detailed description which describes both the preferred and alternative embodiments of the present invention.

Detailed Description of the Invention The composition of the binder system comprises a quaternary system of an alkali metal silicate, a waterborne acrylic resin, an alkali methyl siliconate, and an organofunctional silane. In addition, the quaternary system of active chemicals can be combined with water to form the binder compositions.

In these systems, the percentage of water is between about 50--70k by weight, and the percentage of the quaternary system is between 30-50W by weight.

The alkali metal polysilicates used in the binder composition of the invention are typically selected from sodium silicate, potassium silicate, lithium polysilicate, and mixtures thereof.

Preferably, the alkali metal polysilicate is a lithium polysilicate. The ratio of SiO2 to M20 (M = alkali metal) for the alkali metal polysilicates is preferably between 2:1 and 10:1.

The waterborne acrylic resins used in the invention are aqueous emulsions and stable in the high pH environments associated with binder systems. The acrylic resins can be acrylic polymers or copolymers of acrylic monomers and other monomers such as styrene and butadiene monomers. Commercial examples of acrylic polymers and copolymers for use in the invention are DT 100NATM acrylic emulsion from Dow Chemicals, UCAR Latex 123 and UCAR Latex 471 from Union Carbide, and Rhoplexæ 1018 emulsion and Rhoplex 2200 emulsion from Rohm and Haas Company.

The alkali metal methyl siliconates used in the binder compositions of the invention are preferably potassium or sodium methyl siliconates. More preferably, the alkali metal methyl siliconate is a potassium methyl siliconate.

The organofunctional silanes used in the practice of the invention are preferably water soluble and remain stable in the pH range of between 7 and 11.

Nevertheless, as is well known to those skilled in the art, the stability of the silane is dependent in part on the water percentage in the binder composition. The silane used in the binders compositions can be a monomer or polymerized, for example, to form a dimer or a trimer, as long as the polymerized silanes do not precipitate and separate from the solution. Suitable

silanes for use in the invention include vinyl-tris-(2- methoxyethoxy)silane, -aminopropyltriethoxysilane, - aminopropyltrimethoxysilane, N-P-aminoethyl-y-amino- propyltrimethoxysilane, triaminofunctional silanes, N- <BR> <BR> <BR> <BR> <BR> P-aminoethyl-P-propylmethyldimethoxysilane, P-amino-W- methylethyltriethoxysilane, -aminopropyltriethoxy- silane, -aminobutyltrimethoxysilane, -aminohexyl- triethoxysilane, y-aminopropylmethyldiethoxysilane, - aminopropylphenyldiethoxysilane, N-methyl-y-amino- propyltriethoxysilane, N,N-dimethyl-y-aminopropyltri- ethoxysilane, N-y-aminopropyl-y-aminobutyltriethoxy- silane, aminomethyltrimethoxysilane, P-aminoethyltri- methoxysilane, p-aminoethyltriethoxysilane, y-amino- butyltriethoxysilane, p-methylaminoethyltriethoxy- silane, p-ethylaminoethyltriethoxysilane, y-methyl- aminopropyltrimethoxysilane, -propylaminopropyltri- ethoxysilane, y-ethylaminobutyltriethoxysilane, - phenylaminopropyltrimethoxysilane and -phenylamino- propyltriethoxysilane. All of the above silanes can be hydrolyzed to produce their corresponding silanols and/or siloxanes and employed in the invention in this form. An exemplary silane which can be hydrolyzed to its corresponding silanol and/or siloxane is - aminopropyl-triethoxysilane, a commercial example of which is Siquest 1106 .

The proportion of each component in the quaternary system (i.e., other than water) preferred in the practice of the invention is between about 50-80t alkali metal silicate, about 3-18W acrylic resin, about 5-20t alkali metal methyl siliconate, and about 2-12t organofunctional silane. An exemplary formulation of the quaternary system is 70% alkali metal silicate, 10% acrylic resin, 10% alkali metal methyl siliconate, and 10% organofunctional silane.

The binder composition of the invention is prepared by blending the components of the quaternary system. Typically, the quaternary system is blended

along with water and mixed under constant agitation using a high speed mixer to form the binder. For example, water can be added to the high speed mixer followed by the organofunctional silane, the alkaline metal methyl siliconate, the alkali metal silicate, and the acrylic resin. Other materials such as fillers and additives can also be blended with the binder to provide the desired properties for the painting or coating material. Exemplary fillers include visibility enhancement fillers such as titanium dioxide, calcium carbonate, silica flour, calcined blue flint, calcined clays, and cristobalite; retroreflectivity enhancement fillers such as glass beads and flaked glass; and moisture proof and water repellent materials such as calcium oleate, aluminum stearate, and salts of long carbon chain fatty acids (C10 or greater). Exemplary additives include surfactants such as polyoxyethylene alcohols, ethoxylated nonphenols, dialkylphenol ethoxylates, polyoxyethylene sorbitan monooleate, polyoxyethylene monooleate, and tridecyl ether polyoxyethylene, and ethoxylated octylphenol; defoamers such as silicon defoamers, rheology modifiers such as water-soluble cellulose ethers (e.g. hydroxymethyl cellulose), colloidal clays (e.g. bentonite) and metakaolin; coalescing agents such as propylene glycol butyl ether; crosslinking agents such as a modified diphenylmethane diisocyanate (MDI); coloring pigments; pigment extenders such as anhydrous aluminum silicate; fluorescent pigments such as cadmium sulfide, cadmium selenide, zinc sulfide, strontium sulfide, and copper doped chemicals; coupling agents; and monocyclic or bicyclic oxazolidines to protect the composition against microbial deterioration.

The painting or coating material once prepared can be applied to at least a portion of a surface of a substrate to form a painted or coated substrate. The painting or coating material can be

applied by any suitable method such as by using brush, roller,-trowel, or spray equipment. Typical substrates include metal, ceramic, wood, stone, masonry, cementitious, and bituminous substrates. The painting or coating composition can then be allowed to polymerize and crosslink to form a painted or coated substrate. The resulting painted or coated substrate comprises a substrate and a hardened painting or coating composition bonded to at least a portion of a surface of the substrate. The painting or coating composition comprises the reaction product of the alkali metal silicate, the waterborne acrylic resin, the alkali metal methyl siliconate, and the organofunctional silane. In addition, any fillers or additives used with the binder system are distributed throughout this reaction product.

The hybrid inorganic-organic binder of the invention can be used in colored coatings for transportation and sign markings and to produce protective coatings have certain properties such as water repellant properties, good abrasion resistance, and good wear/deterioration resistance. In addition, the painting and coating materials made with the hybrid binder system of the invention offer several major advantages over traditional organic and traditional inorganic binder systems. Exemplary advantages are as follows: Exceptional resistance to thermal decomposition and oxidation Strong binding ability to various fillers and pigments Strong bonding properties to various types of substrates Environmental friendliness Good abrasion resistance Resistance to W radiation

Resistance to hostile chemicals such as acids and bases Resistance to moisture changes Resistance to freezing and thawing after cured Resistance to common solvents Good recoatability without stripping clean Resistance to chipping and peeling Excellent mechanical properties The binder composition of the invention is compatible with various fillers and additives which can be used to alter the physical, chemical and mechanical properties of the binder composition. Therefore, in addition to the use of the binder composition of the invention in painting and coating compositions, the binder composition can be used in various other applications such as vertical wall applications (e.g., stucco) for the building industry.

It is understood that upon reading the above description of the present invention, one skilled in the art could make changes and variations therefrom.

These changes and variations are included in the spirit and scope of the following appended claims.