Curable film-forming sol-gel compositions and anti-glare coated articles formed from them

Abstract

Curable film-forming sol-gel compositions that are essentially free of inorganic oxide particles are provided. The compositions contain: a tetraalkoxysilane; a solvent component; and non-oxide particles, and further contain either i) a mineral acid or ii) an epoxy functional trialkoxysilane and a metal-containing catalyst. Coated articles demonstrating antiglare properties are also provided, comprising: (a) a substrate having at least one surface; and (b) a cured film-forming composition applied thereon, formed from a curable sol-gel composition comprising a silane and non-oxide particles. A method of forming an antiglare coating on a substrate is also provided. The method comprises: (a) applying a curable film-forming sol-gel composition on at least one surface of the substrate to form a coated substrate; and (b) subjecting the coated substrate to thermal conditions for a time sufficient to effect cure of the sol-gel composition and form a coated substrate with a sol-gel network layer having anti-glare properties.

What is claimed is: 
     
         1 . A curable film-forming sol-gel composition that is essentially free of inorganic oxide particles and comprises:
 (i) a tetraalkoxysilane;   (ii) a mineral acid;   (iii) a solvent component; and   (iv) non-oxide particles.   
     
     
         2 . The composition of  claim 1  wherein the tetraalkoxysilane (i) comprises tetramethoxysilane and/or tetraethoxysilane. 
     
     
         3 . The composition of  claim 1  wherein the mineral acid (ii) comprises nitric acid or hydrochloric acid. 
     
     
         4 . The composition of  claim 1  wherein the non-oxide particles (iv) comprise polystyrene, polyurethane, acrylic, alkyd, polyester, polysulfide, polyepoxide, polyurea, polyolefin, and/or silicone-containing rubber polymers, or are in the form of a latex and comprise hollow-sphere acrylic polymeric particles and/or solid polymeric particles. 
     
     
         5 . A curable film-forming sol-gel composition that is essentially free of inorganic oxide particles and comprises:
 (i) a tetraalkoxysilane;   (ii) an epoxy functional trialkoxysilane;   (iii) a metal-containing catalyst;   (iv) a solvent component; and   (v) non-oxide particles.   
     
     
         6 . The composition of  claim 5  wherein the tetraalkoxysilane (i) comprises tetramethoxysilane and/or tetraethoxysilane. 
     
     
         7 . The composition of  claim 5 , wherein the epoxy functional trialkoxysilane (ii) comprises glycidoxypropyl trimethoxysilane. 
     
     
         8 . The composition of  claim 5  wherein the metal-containing catalyst (iii) comprises colloidal aluminum hydroxychloride or aluminum acetylacetonate. 
     
     
         9 . The composition of  claim 5  wherein the non-oxide particles (v) are inorganic and comprise at least one of Si 3 N 4 , BN, SiC, and ZnS. 
     
     
         10 . The composition of  claim 5  wherein the non-oxide particles (v) comprise polystyrene, polyurethane, acrylic, alkyd, polyester, polysulfide, polyepoxide, polyurea, polyolefin, and/or silicone-containing rubber polymers, or are in the form of a latex and comprise hollow-sphere acrylic polymeric particles and/or solid polymeric particles. 
     
     
         11 . A curable film-forming sol-gel composition that is essentially free of inorganic oxide particles and comprises:
 (i) a tetraalkoxysilane;   (ii) a mineral acid;   (iii) a solvent component; and   (iv) non-oxide particles; wherein the non-oxide particles are selected from the group consisting of Si 3 N 4 ; BN; SiC; Zn; polystyrene; polyurethane; acrylic; alkyd; polyester; polysulfide; polyepoxide; polyurea; polyolefin; silicone-containing rubber polymers; sodium salts of 3-allyloxy-2-hydroxy-1-propanesulfonic acid, 2-Acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, or (meth) acrylic acid; ammonium salts of 3-allyloxy-2-hydroxy-1-propanesulfonic acid, 2-Acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, or (meth) acrylic acid; Vinylbenzyltrimethyl ammonium chloride;   diallyldimethylammonium chloride; dimethylaminoethyl (meth)acrylate; tert-butylaminoethyl methacrylate; trimethyl(2-methacryloxylethyl) ammonium chloride; dimethylaminopropyl (meth)acrylamide; trimethyl(2-methacrylamidopropyl) ammonium chloride; and mixtures thereof; wherein when the non-oxide particles are acrylic or polystyrene polymers, they are added to the film-forming sol-gel composition in the form of cationic or anionic aqueous dispersions of acrylic or polystyrene polymer particles.   
     
     
         12 . The composition of  claim 11  wherein the tetraalkoxysilane (i) comprises tetramethoxysilane and/or tetraethoxysilane. 
     
     
         13 . The composition of  claim 11  wherein the mineral acid (ii) comprises nitric acid or hydrochloric acid. 
     
     
         14 . A coated article demonstrating anti-glare properties, wherein the coated article comprises:
 (a) a substrate having at least one flat surface; and   (b) a cured film-forming composition applied to at least a portion of the flat surface of the substrate, wherein the cured film-forming composition is formed from the curable sol-gel composition of  claim 11 , and wherein the substrate comprises soda-lime-silica glass, aluminosilicate glass, a polymer prepared from polyol(allyl carbonate) monomers, a polymer prepared from polyol(meth)acryloyl terminated carbonate monomer, or thermoplastic polycarbonates;   and wherein the coated article demonstrates a 60° gloss value of 15 to 120 gloss units and a light transmittance of at least 84%.   
     
     
         15 . The coated article of  claim 14 , wherein the coated article comprises a lens. 
     
     
         16 . A curable film-forming sol-gel composition that is essentially free of inorganic oxide particles and comprises:
 (i) a tetraalkoxysilane;   (ii) an epoxy functional trialkoxysilane;   (iii) a metal-containing catalyst;   (iv) a solvent component; and   (v) non-oxide particles; wherein the non-oxide particles are selected from the group consisting of Si 3 N 4 ; BN; SiC; Zn; polystyrene; polyurethane; acrylic; alkyd; polyester; polysulfide; polyepoxide; polyurea; polyolefin; silicone-containing rubber polymers; sodium salts of 3-allyloxy-2-hydroxy-1-propanesulfonic acid, 2-Acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, or (meth) acrylic acid; ammonium salts of 3-allyloxy-2-hydroxy-1-propanesulfonic acid, 2-Acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, or (meth) acrylic acid; Vinylbenzyltrimethyl ammonium chloride; diallyldimethylammonium chloride; dimethylaminoethyl (meth)acrylate; tert-butylaminoethyl methacrylate; trimethyl(2-methacryloxylethyl) ammonium chloride; dimethylaminopropyl (meth)acrylamide; trimethyl(2-methacrylamidopropyl) ammonium chloride; and mixtures thereof; wherein when the non-oxide particles are acrylic or polystyrene polymers, they are added to the film-forming sol-gel composition in the form of cationic or anionic aqueous dispersions of acrylic or polystyrene polymer particles.   
     
     
         17 . The composition of  claim 16  wherein the tetraalkoxysilane (i) comprises tetramethoxysilane and/or tetraethoxysilane. 
     
     
         18 . The composition of  claim 16 , wherein the epoxy functional trialkoxysilane (ii) comprises glycidoxypropyl trimethoxysilane. 
     
     
         19 . The composition of  claim 16  wherein the metal-containing catalyst (iii) comprises colloidal aluminum hydroxychloride or aluminum acetylacetonate. 
     
     
         20 . A coated article demonstrating anti-glare properties, wherein the coated article comprises:
 (a) a substrate having at least one flat surface; and   (b) a cured film-forming composition applied to at least a portion of the flat surface of the substrate, wherein the cured film-forming composition is formed from the curable sol-gel composition of  claim 16 , and wherein the substrate comprises soda-lime-silica glass, aluminosilicate glass, a polymer prepared from polyol(allyl carbonate) monomers, a polymer prepared from polyol(meth)acryloyl terminated carbonate monomer, or thermoplastic polycarbonates;   and wherein the coated article demonstrates a 60° gloss value of 15 to 120 gloss units and a light transmittance of at least 84%.   
     
     
         21 . The coated article of  claim 20 , wherein the coated article comprises a lens.