High gain durable anti-reflective coating with oblate voids
View Patent ↗Disclosed herein are single layer transparent coatings with an anti-reflective property, a hydrophobic property, and that are highly abrasion resistant. The single layer transparent coatings contain a plurality of oblate voids. At least 1% of the oblate voids are open to a surface of the single layer transparent coatings.
1. A single layer transparent coating with an anti-reflective property, a hydrophobic property that is highly abrasion resistant and
wherein the single layer transparent coating contains a plurality of oblate voids, the plurality of oblate voids having a flattening greater than 0.0 and less than or equal to 0.8; and
wherein at least 1% of the oblate voids are open to a surface of the single layer transparent coating.
2. The coating of claim 1 , wherein a thickness of the single layer transparent coating is between 10 nm and 5 μm.
3. The coating of claim 1 , wherein a refractive index of the single layer transparent coating is less than 1.45.
4. The coating of claim 1 , wherein an average reflection of visible light from a surface of glass coated with the single layer transparent coating is less than 3%.
5. The coating of claim 1 , wherein a T AM (solar weighted optical transmission) of a coated glass substrate is at least 1% greater than a T AM of a same type of uncoated glass substrate.
6. The coating of claim 1 , wherein a water contact angle in a test for the hydrophobic property is greater than 70°.
7. The coating of claim 1 , wherein a reduction in optical transmission of the single layer transparent coating as measured by T AM (solar weighted optical transmission) after performance of 1000 strokes of abrasion testing according to the procedure in standard EN1096.2 is less than 1.0%.
8. The coating of claim 1 , wherein a distribution of a void diameter of the oblate voids comprises a Gaussian distribution with a mean of between 10 nm and 150 nm with a standard deviation between 2 nm and 40 nm.
9. The coating of claim 1 , wherein a distribution of void diameter of the oblate voids is bi-modal with a first group having a Gaussian distribution with a mean between 25 nm and 150 nm and a standard deviation between 5 nm and 40 nm and a second group having a Gaussian distribution with a mean between 150 nm and 500 nm and a standard deviation between 25 nm and 50 nm.
10. The coating of claim 1 , wherein at least 1% of the oblate voids extend through a full thickness of the single layer transparent coating.
11. The coating of claim 1 , wherein all of the oblate voids are contained within a full thickness of the single layer transparent coating.
12. The coating of claim 1 , wherein the surface of the single layer transparent coating has a percentage of visible voids between 1% and 50%.
13. The coating of claim 1 , wherein a porosity of the single layer transparent coating is between 50% and 2%.
14. The coating of claim 1 , wherein a major axis of the oblate voids in the single layer transparent coating is between 5 nm and 500 nm and the minor axis of the oblate voids is between 3 nm and 150 nm.
15. The coating of claim 1 , wherein the flattening of one oblate void of the plurality of oblate voids comprises a ratio of a major axis of the oblate void minus a minor axis of the oblate void, divided by the major axis of the oblate void.
16. The coating of claim 1 , wherein the single layer transparent coating is cured at a temperature of less than 400° C.
17. The coating of claim 1 further comprising, a glass substrate having a surface on which said coating is applied.
18. The coating of claim 1 further comprising a solar module having a surface on which said coating is applied.