ANTI-REFLECTION GLASS MADE FROM AGED SOL INCLUDING MIXTURE OF TRI-ALKOXYSILANE AND TETRA-ALKOXYSILANE
A method of making a coated article including an anti-reflection coating on a glass substrate, the method comprising: mixing at least a tri-alkoxysilane based binder and a tetra-alkoxysilane based binder with at least silica based nanoparticles and a solvent in forming a coating sol formulation; aging the coating sol formulation at least about two weeks so as to provide an aged coating sol formulation; coating at least a portion of said aged coating sol formulation onto the glass substrate to form a coating; and heating said glass substrate and said coating. Anti-reflection (AR) glasses show improved mechanical strength and higher transmittances (e.g., Tqe % gain).
1 . A method of making a coated article including an anti-reflection coating on a glass substrate, the method comprising:
mixing at least a tri-alkoxysilane based binder and a tetra-alkoxysilane based binder with at least silica based nanoparticles and a solvent in forming a coating sol formulation;
aging the coating sol formulation at least about two weeks so as to provide an aged coating sol formulation;
coating at least a portion of said aged coating sol formulation onto the glass substrate to form a coating; and
heating said glass substrate and said coating.
2 . A method according to claim 1 , comprising curing the coating via at least said heating.
3 . A method according to claim 1 , wherein the alkyltrialkoxysilane-based binder comprises:
wherein R 1 , R 2 , and R 3 are the same or different and each represents an alkyl group containing 1 to 20 carbon atoms, an aryl group containing 6 to 20 carbon atoms, or an aralkyl group containing 7 to 20 carbon atoms;
wherein R 4 represents an alkyl group containing 1 to 20 carbon atoms, an aryl group containing 6 to 20 carbon atoms, an aralkyl group containing 7 to 20 carbon atoms, or a fluoro-modified alkyl group containing 1 to 20 carbon atoms.
4 . A method according to claim 1 , wherein a mass ratio of the tri-alkoxysilane based binder and tetra-alkoxysilane based binder to the silica based nanoparticles in the coating sol formulation is from 0.1:1 to 20:1.
5 . The method of claim 1 , wherein the tri-alkoxysilane based binder comprises from about 10 wt. % to about 80 wt. % ash contribution in the total ash content of the coating formulation.
6 . The method of claim 1 , wherein the tri-alkoxysilane based binder is selected from the group consisting of n-propyltriethoxysilane, n-pentyltriethoxysilane, n-hexyltriethoxysilane, cyclohexyltrimethoxysilane, and combinations thereof.
7 . The method of claim 1 , wherein the tri-alkoxysilane based binder comprises cyclohexyltrimethoxysilane.
8 . The method of claim 1 , comprising forming a gel on the glass substrate by drying the coating sol formulation coated on the glass substrate prior to annealing the coated glass substrate.
9 . The method of claim 1 , wherein silica based nanoparticles in the coating sol formulation have a shape selected from spherical, elongated, disc-shaped, and combinations thereof.
10 . The method of claim 1 , wherein silica based nanoparticles in the coating sol are selected from spherical particles having a particle size from about 40 to 50 nm, spherical particles having a particle size from about 70 to 100 nm, spherical particles having a particle size from about 10 to 15 nm, spherical particles having a particle size from about 17 to 23 nm, elongated particles having a diameter from 9 to 15 nm and length of 40 to 100 nm, and combinations thereof.
11 . The method of claim 1 , wherein the solvent comprises an alcohol containing solvent, and wherein the coating sol formulation further includes an acid or base containing catalyst.
12 . A method according to claim 1 , wherein in the coating sol formulation the amount of tetra-alkoxysilane based binder is from about 15-80% (wt. %) of the combination of the tetra-alkoxysilane based binder and the tri-alkoxysilane based binder.
13 . A method according to claim 1 , wherein in the coating sol formulation the amount of tetra-alkoxysilane based binder is from about 20-70% (wt. %) of the combination of the tetra-alkoxysilane based binder and the tri-alkoxysilane based binder.
14 . A method according to claim 1 , wherein in the coating sol formulation the amount of tetra-alkoxysilane based binder is from about 40-60% (wt. %) of the combination of the tetra-alkoxysilane based binder and the tri-alkoxysilane based binder.
15 . A method according to claim 1 , wherein said glass substrate is a matte-matte glass.
16 . A method according to claim 1 , wherein said glass substrate comprises soda-lime-silica based float glass.
17 . A method according to claim 1 , wherein said coating step comprises spin coating or dip coating.
18 . A method according to claim 1 , wherein visible transmittance is increased by at least about 2.8% as a result of said coating being applied and cured on the glass substrate.
19 . A method according to claim 1 , wherein the thickness of said coating after curing is from about 120 to 140 nm.
20 . A method according to claim 1 , wherein refractive index of said coating following curing is from about 1.25 to 1.30.
21 . A method according to claim 1 , wherein said heating comprises heating the coated glass substrate at temperature(s) of at least about 580 degrees C. for at least about 1 minute.
22 . The method of claim 1 , wherein the coating sol formulation includes water, acetic acid and n-propyl alcohol.
23 . The method of claim 1 , wherein said aging comprises aging the coating sol formulation at least about three weeks so as to provided the aged coating sol formulation.
24 . The method of claim 1 , wherein said solvent comprises NPA.
25 . The method of claim 1 , wherein the tetra-alkoxysilane based binder comprises TEOS.
26 . The method of claim 1 , wherein the coating is applied directly on the glass substrate.
27 . A method of making a coated article including an anti-reflection coating on a substrate, the method comprising:
mixing at least a tri-alkoxysilane based binder with a tetra-alkoxysilane based binder and silica based nanoparticles in forming a wet coating formulation;
aging the wet coating formulation at least about ten days so as to provided an aged wet coating formulation;
coating at least a portion of said aged wet coating formulation onto the glass substrate to form a coating; and
curing the coating.
28 . A method of making a coated article including an anti-reflection coating on a substrate, the method comprising:
mixing at least a tri-alkoxysilane based binder and a tetra-alkoxysilane based binder with at least silica based nanoparticles and a solvent in forming a coating sol formulation;
aging the coating sol formulation for a period of time sufficient for both hydrolysis and condensation to occur so as to provide an aged coating sol formulation;
coating at least a portion of said aged coating sol formulation onto the glass substrate to form a coating; and
heating said glass substrate and said coating.
29 . The method of claim 28 , wherein said aging is for at least ten days.
30 . The method of claim 28 , wherein said aging is for at least two weeks.
31 . The method of claim 28 , wherein said aging is at approximately room temperature.