SURFACE COATING COMPOSITION WITH LONG DURABILITY

Abstract

The present invention relates to a coating composition comprising (A) hydrophobically modified fumed silica particles, (B) one or more compounds of hydrolyzed organosilanes, and (C) a solvent or mixture of solvents. The coating composition may be used to treat substrates such as glass surface to make the substrate surfaces possess valuable properties such as water repellency, dirt repellency and self-cleaning with water.

Claims

1-16. (canceled)

17. A composition comprising the following components: a) hydrophobically modified fumed silica particles with a median particle size of from 100 to 100,000 nm; b) one or more organosilanol compounds selected from the group consisting of: compounds of Formula (I), wherein Formula (I) is:
X—R—Si(OH).sub.mY.sup.1.sub.nY.sup.2.sub.o  (I) wherein: X is a non-hydrolyzable linear, branched or unbranched aliphatic alkyl residue with 1 to 12 carbon atoms, optionally substituted with fluorine or chlorine atoms; or is a functional group selected from the group consisting of: amino, epoxy, vinyl, methacrylate, or sulfur groups; R is a spacer and is either an aryl or alkyl chain; Y.sup.1 and Y.sup.2 are identical or different and each is independently a hydrolysable or non-hydrolyzable moiety selected from the group consisting of: linear, branched or unbranched, alkyl groups with 1 to 12 carbon atoms; aryl groups with 6 to 12 carbon atoms; halogens; alkoxy groups with 1 to 12, carbon atoms; and acyl groups with 1 to 12 carbon atoms; with the provisio that at least one of Y.sup.1 and Y.sup.2 is hydrolyzable and is selected from the group consisting of: halogens, alkoxy groups with 1 to 12 carbon atoms; and acyl groups with 1 to 12 carbon atoms; m=1, 2 or 3; n and o are each 0 or 1, but are selected such that m+n+o=3; and dimeric compounds of Formula (I); trimeric compounds of Formula (I); and oligomeric compounds formed by a self-condensation reaction of up to 8 molecules according to Formula (I), provided that the compounds have at least one or two free —OH groups; c) a solvent or mixture of solvents.

18. The composition of claim 17, wherein: X is a linear, branched or unbranched aliphatic alkyl residue with 1 to 6 carbon atoms, optionally substituted with fluorine or chlorine atoms; R is (CH.sub.2)q wherein q=2 or 3; Y.sup.1 and Y.sup.2 are identical or different and each is a hydrolysable or non-hydrolysable moiety selected from the group consisting of: methyl, ethyl and propyl groups; a cyclic aliphatic alkyl group with 1 to 6 carbon atoms; chlorine, an alkoxy selected from the group consisting of: methoxy, ethoxy, isopropoxy; and formyl or acetyl groups, with the provisio that at least one of Y.sup.1 and Y.sup.2 is selected from the group consisting of chlorine, methoxy, ethoxy, isopropoxy and n-propoxy; and a formyl or acetyl group; m=2 or 3.

19. The composition of claim 17, wherein: X is a linear, branched or unbranched aliphatic alkyl residue with 1 to 6 carbon atoms, optionally substituted with fluorine; Y.sup.1 and Y.sup.2 are each independently methyl; a cyclic aliphatic alkyl group with 1 to 6 carbon atoms; chlorine; or a methoxy, ethoxy, or isopropoxy group.

20. The composition of claim 17, wherein component (B) of Formula I, is a reaction product of the hydrolyzation of an organosilane of Formula (II) with water and a catalyst, wherein Formula (II) is:
X—R—SiY.sup.1Y.sup.2Y.sup.3  (II) and wherein X and R are defined as in claim 17 and Y.sup.1, Y.sup.2 and Y.sup.3 are identical or different and each is a hydrolysable or non-hydrolyzable moiety, with the proviso that at least one of Y′, Y.sup.2 and Y.sup.3 is hydrolysable.

21. The composition of claim 20, wherein the hydrolyzable organosilane is a hydrolyzable fluoroalkylsilane of the general formula (III):
CF.sub.3(CF.sub.2).sub.n(CH.sub.2).sub.2Si(CH.sub.3).sub.yX′.sub.3-y  (III), in which X′ is a group selected from chlorine, methoxy, ethoxy, isopropoxy, and n-propoxy; n is a number from the series 3, 4, 5, 6, 7, 8, and 9; and y is 0 or 1.

22. The composition of claim 20, wherein the hydrolyzable organosilane is selected from the group consisting of: CF.sub.3—(CF.sub.2).sub.5—(CH.sub.2).sub.2—Si(OCH.sub.3).sub.3; CF.sub.3—(CF.sub.2).sub.5—(CH.sub.2).sub.2—Si(OC.sub.2H.sub.5).sub.3; CF.sub.3—(CF.sub.2).sub.5—(CH.sub.2).sub.2—SiCl.sub.3; CF.sub.3—(CF.sub.2).sub.5—(CH.sub.2).sub.2—Si(CH.sub.3)Cl.sub.2; CF.sub.3—(CF.sub.2).sub.7—(CH.sub.2).sub.2—SiCl.sub.3; CF.sub.3—(CF.sub.2).sub.7—(CH.sub.2).sub.2—Si(OCH.sub.3).sub.3; CF.sub.3—(CF.sub.2).sub.7—(CH.sub.2).sub.2—Si(OC.sub.2H.sub.5).sub.3; C.sub.10F.sub.21—(CH.sub.2).sub.2—Si(OCH.sub.3).sub.3; C.sub.10F.sub.21—(CH.sub.2).sub.2—Si(OC.sub.2H.sub.5).sub.3; C.sub.10F.sub.21—(CH.sub.2).sub.2—SiCl.sub.3; and mixtures thereof.

23. The composition of claim 17, wherein the amount of solvent or solvent mixture is from 30 wt. % to 99.89 wt. %, based on the total weight of the composition, and/or the solvent or solvent mixture is selected from the group consisting of: linear, branched or cyclic aliphatic hydrocarbons with 2 to 14 carbon atoms, optionally substituted with fluorine or chlorine atoms; aromatic hydrocarbons with 6 to 12 carbon atoms, optionally substituted with fluorine or chlorine atoms; monovalent linear or branched alcohols with 1 to 6 carbon atoms; ketones or aldehydes with 1 to 6 carbon atoms; ethers or esters with 2 to 8 carbon atoms; linear or cyclic polydimethylsiloxanes with 2 to 10 dimethylsiloxy units; and mixtures thereof.

24. The composition of claim 17, wherein the concentration of the hydrophobically modified fumed silica is not less than 0.1 wt. %, based on the total weight of the composition and/or the hydrophobically modified silica particles have a median particle size in the range of from 100 to 50,000 nm.

25. The composition of claim 17, wherein the ratio of component (B), in sum of all individual components thereof, to the hydrophobically modified fumed silica in component (A) is in the range of 0.019:1 to 20.92:1; and/or the content of compounds of component B in claim 17 in sum in the composition, is higher than the content of polysiloxanes formed from compounds according to Formula (I).

26. The composition of claim 17, wherein the composition further comprises component (D), a compound of general formula (IV) or (V):
(R.sup.1R.sup.2R.sup.3Si).sub.2NR.sup.4  (IV)
—(R.sup.1R.sup.2SiNR.sup.4).sub.m-(cyclo)  (V) wherein R.sup.1, R.sup.2, and R.sup.3 can be the same or different, and are independently selected from: hydrogen; linear or branched, saturated or unsaturated alkyl chain groups of from 1 to 8 carbon atoms; and aromatic groups of from 6 to 12 carbon atoms; R.sup.4 is hydrogen or a methyl group; and m is from 3 to 8.

27. A process for the preparation of a composition of claim 17, wherein the process comprises the steps: a) preparing a silica dispersion comprising hydrophobically modified fumed silica as defined in claim 17 and a solvent or solvent mixture selected from the group consisting of: linear, branched or cyclic aliphatic hydrocarbons with 2 to 14 carbon atoms, optionally substituted with fluorine or chlorine atoms; aromatic hydrocarbons with 6 to 12 carbon atoms, optionally substituted with fluorine or chlorine atoms; monovalent linear or branched alcohols with 1 to 6 carbon atoms; ketones or aldehydes with 1 to 6 carbon atoms; ethers or esters with 2 to 8 carbon atoms; linear or cyclic polydimethylsiloxanes with 2 to 10 dimethylsiloxy units; and mixtures thereof; b) preparing a hydrolyzed organosilane component (B) by hydrolyzation of: i) at least one hydrolyzable organosilane according to Formula (II):
X—R—SiY.sup.1Y.sup.2Y.sup.3  (II) wherein X, and R, are defined as in claim 17 and Y.sup.1, Y.sup.2 and Y.sup.3 are identical or different and are each a hydrolysable or non-hydrolyzable moiety, with the provisio that at least one of Y.sup.1, Y.sup.2 and Y.sup.3 is hydrolysable. ii) a catalyst; and iii) water; c) mixing the silica dispersion from step a) with the hydrolyzed organosilane composition obtained in step b) and optionally a further solvent or solvent mixture.

28. The process of claim 27, wherein the silica dispersion in step a) comprises from 60 to 95% by weight of a solvent or solvent mixture based on the overall weight of the dispersion; and/or the silica dispersion in step a) comprises 5 to 30 wt. % of hydrophobically modified fumed silica based on the overall composition of the dispersion; and/or the silica dispersion in step a) comprises 0.1 to 10 percent by weight of the total weight of the dispersion of compounds of Formula (II) as defined in claim 20 and/or Formula (III) as defined in claim 21.

29. The process of claim 27, wherein shear forces are applied to the dispersion to adjust the average particle size distribution to a desired particle size.

30. The process of claim 27, wherein step a) comprises: a1) providing a pre-dispersion comprising hydrophobically modified fumed silica particles by stirring said silica particles into a solution comprising: i) at least one compound of general Formula (IV) or (V), wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are defined as above; and ii) a first solvent or solvent mixture selected from: straight or branched, linear or cyclic aliphatic, or aromatic hydrocarbons with 2 to 14 carbon atoms, optionally substituted with fluorine or chlorine atoms; monovalent linear or branched alcohols with 1 to 6 carbon atoms; ketones or aldehydes with 1 to 6 carbon atoms; ethers or esters with 2 to 8 carbon atoms; or linear or cyclic polydimethylsiloxanes with 2 to 10 dimethylsiloxy units, wherein the concentration of the hydrophobically modified fumed silica particles in the pre-dispersion is from 10 to about 30 percent by weight of the total weight of the pre-dispersion, and wherein the concentration of any one of compounds according to Formula (IV) and/or (V) is between 0.1 and 10 percent by weight of the total weight of the pre-dispersion; and a2) mixing said pre-dispersion with a disperser to provide a silica dispersion while reducing said silica particles to a median particle size as defined for component (A) above.

31. The process of claim 27, wherein step b) comprises: mixing the hydrolyzable organosilane of Formula (II) with water and a catalyst; stirring the mixture thus obtained for 1 to 4 hours, at a temperature of 0 to 80° C.; and choosing a molar ratio of hydrolyzable organosilane to water in a range of 1:4.5 to 1:9.

32. The process of claim 27, wherein the solvent or solvent mixture added in step a) and c) are the same.

33. The process of claim 27, wherein the solvent or solvent mixture added in step a) and c) are different.

34. The process of claim 27, wherein the silica dispersion of step a) is prepared according to a process comprising: suspending hydrophobic particles having an average particle diameter of from 100 to 100,000 nm in a solution of a silicone wax in a highly volatile siloxane, wherein said silicone wax is liquid at room temperature and said highly volatile siloxane is liquid at room temperature and comprises at least one compound of general Formula (VI), a cyclic compound of general Formula (VII) or a mixture thereof: ##STR00003## wherein n is a number from 2 to 10.

35. An article which comprises at least one surface treated by the composition of claim 17.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0148] FIG. 1 shows a photo of a water drop on surface of the product coated with the coating composition of the Example 8.

[0149] FIG. 2 shows a photo of water drop on surface of the product after the surface of the coated product was gently wiped by finger.

[0150] FIG. 3 shows a photo of the water drop on surface of the product before coating.

ANALYTIC METHODS

Median Particle Size

[0151] The median particle size was measured using a Horiba LA 910 (use of 1.0 micron polystyrene dispersion as calibration standard, measurement of sample dispersions diluted with isopropyl alcohol and with Relative Refractive Index=1.10). This instrument measures the size and distribution of particles suspended in liquid using laser diffraction.

Durability Test

[0152] Durability test was conducted according the process below:

1) Using a separating funnel to control the generation of droplets in a speed of ≣2 drops/second. The height (from lower end of funnel to mirror surface) is ˜25 cm. Count the drops until the coating is destroyed with visible water adhere on the mirror;
2) Notice to keep the funnel stable throughout the drop-test cycle to make sure that droplets always hit the same sample point of mirror surface; and
3) Once one cycle is finished, change to another area of the mirror and repeat. Take the average of 2-3 cycles as the durability test result.

Contact Angle Analysis

[0153] Contact angle analysis were performed by an electronic water drop angle tester, type MHT-SD2, commercially available from Shenzhen Zhongzheng Instrument Co. Ltd., China.

EXAMPLES

[0154] The invention is now described in detail by the following examples. The scope of the invention should not be limited to the embodiments of the examples.

Hydrophobically Modified Fumed Silica Dispersion

Example A(a)

[0155] A quantity of 0.5 g of hexamethyldisilazane (DYNASYLAN® HMDS, Evonik Industries AG) was dissolved in 74.5 g of decamethylcyclopentasiloxane (TEGO® Polish Additiv 5, also designated as siloxane “D5”, Evonik Industries AG). 25 g of a commercially available, hydrophobized fumed silica with a BET surface area of 220 m.sup.2/g (AEROSIL® R 812 S, Evonik Industries AG) was slowly dispersed in this solution with gentle stirring at 2000 r.p.m. After all fumed silica had been added, the mixing speed of the Dispermat (single rotating shaft, outfitted with saw-tooth blade proportional to mixing vessel where blade is half the diameter of vessel) was increased to 10,000 r.p.m. and kept operating at this speed for 5 min.

Example A(b)-A(d)

[0156] Preparation of example A(b) through A(c) followed the same procedure as for example A(a) except using otherwise specified parameters as shown in Table 1 below. Preparation of example A(d) followed the same procedure as for example A(a) except that hexamethyldisilazane was replaced by 2 wt. % of TEGOPREN® 6814 (Evonik Industries AG), an alkyl-modified polydimethylsiloxane with a molar mass of 13000 g/mol and a recrystallization point of <5° C.

[0157] Example A(a) through Example A(c) in Table 1 are representative embodiments of materials prepared in the form of silica dispersion according to the process disclosed in U.S. Pat. Pub. No. 2006/0110541A1.

[0158] Example A(d) is an representative example of the silica dispersion obtained by following the process disclosed in U.S. Pat. Pub. No. 2004/0213904A1.

TABLE-US-00001 TABLE 1 Silica dispersions prepared according to Examples A(a)-A(d) Particle size AEROSIL ® DYNASYLAN ® TEGOPREN ® Stirrer distribution Composition R 812 S HMDS D5 6814 speed Time (median) example wt. % wt. % wt. % wt. % r.p.m. min. nanometer A(a) 25.0 0.5 74.5 — 10,000 .sup.  5 283 A(b) 25.0 0.5 74.5 — 5,000.sup.  15 2,115 A(c) 10.0 0.5 89.5 — 5,000.sup.(1) 5 3,771 A(d) 5.0 — 93.0 2.0 5,000.sup.(1) 15 41,265 .sup.(1)Examples A(c) and A(d) were unable to be processed at 10,000 r.p.m.

[0159] Examples A(aa) through A(dd) are examples of compositions obtained by further diluting the compositions in Table 1 with D5.

TABLE-US-00002 TABLE 2 Diluted Component A(aa)-A(cc).sup.(2) Component A(aa)wt. % A(bb)wt. % A(cc)wt. % A(a) 20.0 — — A(b) — 20.0 — A(c) — — 50.0 D5 80.0 80.0 50.0 .sup.(2)All diluted compositions had an active silica level of ~5 wt. %.

Hydrolyzed Organosilane Composition (Component (B))

[0160] The reactions indicated below in the examples B(a)-B(e) were each carried out in a heatable and coolable reaction apparatus with stirrer, metering means, condenser, water bath, and thermometer.

Example B(01)

[0161] A 100 ml glass stirring apparatus with metering means, reflux condenser, and water bath was charged with 20 g of Dynasylan® F 8261 (tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, Evonik Industries AG), 4 g of deionized water, and 0.2 g of hydrochloric acid (37% HCl). The molar silane:water ratio was 1:5.8. Immediately after the addition of the hydrochloric acid the temperature rose within 5 minutes from room temperature to 30° C. The batch (i.e. reaction mixture) was subsequently stirred at 26° C. for 3 hours, and the final product was the ready-to-use Component B(01).

Example B(a) and B(b)

[0162] A 100 ml glass stirring apparatus with metering means, reflux condenser, and water bath was charged with 20 g of Dynasylan® F 8261 (tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, Evonik Industries AG), 4 g of deionized water, and 0.2 g of hydrochloric acid (37% HCl). The molar silane:water ratio was 1:5.8. Immediately after the addition of the hydrochloric acid the temperature rose within 5 minutes to 30° C. The batch was subsequently stirred at 26° C. for 3 hours. It was then diluted with 975.8 g of D5 or isopropanol (“IPA”) in a 2 L glass bottle to give the ready-to-use Component B(a) and Component B(b) respectively.

Example B(c) and B(d)

[0163] A 100 ml glass stirring apparatus with metering means, reflux condenser, and water bath was charged with 20 g of Dynasylan® F 8261 (tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, Evonik Industries AG), 26 g of isopropanol, 4 g of deionized water, and 0.2 g of hydrochloric acid (37% HCl). The molar silane:water ratio was 1:5.8. Immediately after the addition of the hydrochloric acid the temperature rose within 5 minutes to 30° C. The batch was subsequently stirred at 26° C. for 3 hours. It was then diluted with 950 g of D5 or isopropanol in a 2 L glass bottle to give the ready-to-use Component B(c) and Component B(d) respectively.

Example B(02)

[0164] A 100 ml glass stirring apparatus with metering means, reflux condenser, and water bath was charged with 20 g of octyltriethoxysilane (Dynasylan® OCTEO, Evonik Industries AG), 22.4 g of isopropanol, 7.4 g of deionized water, and 0.2 g of hydrochloric acid (37% HCl). The molar silane:water ratio was 1:5.8. Immediately after the addition of the hydrochloric acid the temperature rose within 5 minutes to 30° C. The batch was subsequently stirred at 26° C. for 3 hours, and the final product was the ready-to-use Component B(02).

Example B(e)

[0165] A 100 ml glass stirring apparatus with metering means, reflux condenser, and water bath was charged with 20 g of octyltriethoxysilane (Dynasylan® OCTEO, Evonik Industries AG), 22.4 g of isopropanol, 7.4 g of deionized water, and 0.2 g of hydrochloric acid (37% HCl). The molar silane:water ratio was 1:5.8. Immediately after the addition of the hydrochloric acid the temperature rose within 5 minutes to 30° C. The batch was subsequently stirred at 26° C. for 3 hours. It was then diluted with 950 g of isopropanol in a 2 L glass bottle to give the ready-to-use Component B(e).

[0166] In TABLE 3, the Examples Component B (a)-B(d) comprised around 1.67 wt. % of hydrolyzed tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, Component B(e) comprised around 1.39 wt. % of hydrolyzed octyltriethoxysilane.

TABLE-US-00003 TABLE 3 Component B(a)-B(e) Examples of Ingredients for silane hydrolysis reaction Diluent after Component B F 8261* OCTEO** DI water 37% HCl IPA reaction B (01) 20 g — 4 g 0.2 g — — B (a) 20 g — 4 g 0.2 g — 975.8 g D5 B (b) 20 g — 4 g 0.2 g — 975.8 g IPA B (c) 20 g — 4 g 0.2 g 26 g 949.8 g D5 B (d) 20 g — 4 g 0.2 g 26 g 949.8 g IPA B (02) — 20 g 7.4 g 0.2 g 22.4 g — B (e) — 20 g 7.4 g 0.2 g 22.4 g 950 g IPA *F 8261 represents tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane (Dynasylan ® F 8261), **OCTEO represents octyltriethoxysilane.

Comparative Example B(f) and B(g)

[0167] To prepare Comparative 8 and Comparative 9 below, Components B(f) and B(g) were prepared by hydrolyzation of the organosilane according to Formula (II) with water under a basic catalyst. The preparation of Components B(f) and B(g) were the same as Components B(c) and B(d), respectively, excepted that 37% HCl in Components B(c) and B(d) was replaced by 37% NaOH in Components B(f) and B(g). See Table 4 for details of the preparation conditions.

[0168] For both Components B(f) and B(g), lots of insoluble white aggregate could be observed in the hydrolyzed product after the base-catalyzed hydrolysis of silane. This can be explained by the fact that at alkaline pH condition, the hydrolyzed product of silane hydrolysis reaction would typically self-condensate to high molecular weight species—the insoluble white aggregates. The insoluble aggregate, i.e., the self-condensation product does not contribute to the coating durability improvement.

TABLE-US-00004 TABLE 4 Component B(f) and B(g) Comparative Examples of Ingredients for silane hydrolysis reaction Component B F8261 DI water 37% NaOH IPA Diluent after reaction B (f)*** 20 g 4 g 0.2 g 26 g 949.8 g D5 B (g)**** 20 g 4 g 0.2 g 26 g 949.8 g IPA ***B (f) appears hazy and some white aggregates generated ****B (g) bigger white aggregates generated compared to B (f)

Final Inventive Composition

Preparation Method of the Composition of the Invention

[0169] The composition of the invention was prepared according to the following process:

[0170] Blend components A and B with stirring. If component C was present, add component C to a container first then followed by components A and B. The product was a homogeneous, slightly white turbid liquid.

[0171] The compositions of the inventive examples 1-16 and comparative examples 1-7 were applied to a smooth glass surface.

Application Method of the Composition of the Invention

[0172] The composition of the invention was applied to a substrate surface according to the method as follows,

1) Ensure that the glass surface is clean and completely dry,
2) Spray the composition onto the glass surface, spray distance from the sprayer nozzle to the glass surface should be ˜25 cm to provide an even surface distribution. For a 10 cm*13 cm mirror surface, normally 4-6 sprays will ensure complete coverage of the liquid on the mirror, and
3) The surface layer should be allowed to dry completely.

[0173] Durability tests of the compositions of the inventive examples and comparative examples were done according to the method described above.

[0174] The results of the durability tests are shown in Tables 5-8.

TABLE-US-00005 TABLE 5 Inventive Composition 1-5 and the corresponding durability results comparing to Comparative examples 1-4 Durability Example No. Component A Component B D5 (drops) Comparative 1 15% A(aa) — 85% 1-2 Comparative 2 15% A(aa) 0.1% F 8261 84.9%.sup.   8-10 1 15% A(aa) 5% B(a) 80% 20-25 2 15% A(aa) 5% B(c) 80% 35-40 3 15% A(aa) 5% B(d) 80% >200 Comparative 3 15% A(aa) 0.1% OCTEO 84.9%.sup.    1 4 15% A(aa) 5% B(e) 80% 80-85 Comparative 4 10% A(d) — 90%  <10 5 10% A(d) 5% B(c) 85% 100-105

[0175] As shown in TABLE 5, the Inventive Composition 1-5 had surprisingly much better durability than Comparative examples 1-4.

TABLE-US-00006 TABLE 6 Inventive Compositions 4, 6-13 and the corresponding durability results comparing to Comparative examples 5-6 wt % Durability ratio(organosilanol:active No. Component A Component B D5 (drops) silica) Comparative 5 100% A(aa) — — 15-20 — 6 85% A(aa) 15% B(a) — 40-45 0.0590:1 7 80% A(aa) 20% B(a) — >140 0.0839:1 8 75% A(aa) 25% B(a) — >200 0.1118:1 9 95% A(aa) 5% B(01) — >200 0.7295:1 10 5% A(aa) 1.5% B(01) 93.5%.sup.  >200 4.1417:1 Comparative 6 15% A(aa) — 85% 1-2 — 11 15% A(aa) 1.4% B(e) 83.6%.sup.   8-12 0.0259:1 12 15% A(aa) 2% B(e) 83% 12-15 0.0371:1 4 15% A(aa) 5% B(e) 80% 80-85 0.0930:1 13 5% A(aa) 0.589% B(02) 94.411%    >200 0.6556:1

TABLE-US-00007 TABLE 7 Inventive Composition 14-16 and the corresponding durability results comparing to Comparative example 7 wt % Active Durability ratio(organosilanol:active silica No. Component A Component B D5 (drops) silica) wt. % Comparative 7 15% A(aa) — 85% 1-2 — 0.75% 14 5% A(aa) 1.67% B(d) 93.33%   25-30 0.1116:1 0.25% 15 3% A(aa) 1% B(d) 96% 10-15 0.1113:1 0.15% 16 3% A(aa) 0.158% B(01) 96.842%    30-33 0.7271:1 0.15%

[0176] As shown in Tables 6 and 7, the Inventive Composition 4, 6-16 had surprisingly much better durability than Comparative examples 5-7.

TABLE-US-00008 TABLE 8 Durability test results of Comparative example 8 and Comparative example 9 Durability Example No. Component A Component B D5 (drops) Comparative 1 15% A(aa) — 85% 1-2 2 15% A(aa) 5% B(c) 80% 35-40 3 15% A(aa) 5% B(d) 80% >200 Comparative 8 15% A(aa) 5% B(f) 80% 3 Comparative 9 10% A(d) 5% B(g) 80% <4

[0177] As shown in Table 8, when the hydrolyzation of the organosilane according to Formula (II) with water was performed under a basic catalyst, the prepared coating compositions had no durability improvement and thus were not within the scope of the present invention.

Example 20: Contact Angle Analysis

[0178] The contact angle of pure water on the mirror treated by Inventive Compositions were tested by an electronic water drop angle tester.

[0179] The contact angle of pure water on the mirror treated by Inventive Composition 3 was ˜152°.

[0180] The other Inventive Compositions also showed a contact angle above 140°.

[0181] Thus, the contact angle of pure water on the surface treated by Inventive Compositions was very high.

Example 21: Water Drops on Different Surfaces

[0182] FIGS. 1-3 shows the appearance of water drops on different surfaces. The tests were performed according to the following procedure:

[0183] FIG. 3:

1) Ensure that a substrate (glass) surface is clean and completely dry,
2) Drop pure water dropwise onto the glass surface before coated with the composition of Example 8, and
3) Take a photo of the glass surface with water,

FIG. 1:

[0184] 1) Ensure that the glass surface is clean and completely dry,
2) Spray the composition of Example 8 onto the glass surface. The distance from the sprayer nozzle to the substrate surface for an aerosol was −20 cm to provide an even surface distribution, allow the surface to dry in air completely,
3) Drop pure water dropwise onto the coated glass surface, and
4) Take a photo of the glass surface with water.

FIG. 2:

[0185] 1) Ensure that the glass surface is clean and completely dry,
2) Spray the composition of Example 8 onto the glass surface. The distance from the sprayer nozzle to the substrate surface for an aerosol was −20 cm to provide an even surface distribution, allow the surface to dry in air completely,
3) Wipe the coated glass surface gently by a finger,
4) Drop pure water dropwise onto the coated glass surface gently wiped by finger, and
5) Take a photo of the glass surface with water.

[0186] As shown in FIG. 3, the uncoated glass surface was hydrophilic and was immersed by water. After the glass surface was coated by the composition of Example 8, as shown in FIG. 1, the glass surface was super-hydrophobic, and the shape of water drop was nearly spherical. After the coated glass surface was gently wiped by finger, as shown in FIG. 2, the shape of water drop was nearly flat but cannot spread out (much smaller contact angle), this suggested that there was a layer of silica particles on the top of the coated surface and the silica particles were wiped out by finger. After wiped by finger, the surface was still hydrophobic but the hydrophobicity was substantially reduced, and only the hydrolyzed silane played a role of water repellency.

Comparative Example 10

[0187] A glass surface was coated using:

Component (B) and

[0188] a silica dispersion comprising Component (A) and a solvent,
one by one, with the following procedure:
a) Spray Component (B) prepared in Example B(d) onto a glass surface and let it form a coating layer by drying first, then
b) Spay the silica dispersion prepared in Comparative example 1 onto the Component (B) coating layer.

[0189] It could be observed that it was difficult for Component (A) to wet the surface and Component (A) shrank to form droplets. Thus, Component (A) could not form a homogeneous coating on the surface pretreated by Component (B). The coating composition of the invention comprising the Component (B) and Component (A) could not be formed. This indicated that the coating composition of the invention comprising the Component (B) and Component (A) as a whole was important to show good performances like super-hydrophobicity.