Transparent textured substrate and methods for obtaining same
The invention concerns a transparent substrate whereof part at least of the outer surface has the form of a web comprising protuberances, 80% of them at least, having heights ranging between 40 and 250 nm, mean diameters between 1 and 500 nm, 80% at least of the distances between two neighbouring protuberances ranging between 1 and 500 nm. The invention further provides two methods for making said substrates and its use in a transport vehicle glazing, for a building, or for an indoor or outdoor decorative element, for urban environment or for household appliance, in a lenticular screen or microprism substrate, in an engraved glass substrate for lamp or display, and in a chemical or biochemical microreactor.
1. A substrate, comprising:
a layer comprising a material selected from the group consisting of glass, silica and a polymeric material, wherein:
at least a portion of an outer surface of the layer has a geometry of a sheet provided with irregular protuberances having substantially flat tops;
at least 80% of the protuberances have heights of between 40 and 250 nm and mean diameters of between 1 and 500 nm;
at least 80% of adjacent protuberances are separated by a distance of between 1 and 500 nm; and
the protuberances are obtained by etching a precursor layer through a mask.
2. The substrate according to claim 1 , wherein at least 80% of the protuberances have heights of at least 60 nm.
3. The substrate according to claim 1 , wherein at least 80% of the protuberances have heights 190 nm or less.
4. The substrate according to claim 1 , wherein at least 80% of the protuberances are substantially right frustums of cones having axes perpendicular to a principal plane of the substrate and having half-angles at apex of between 0 and 60°.
5. The substrate according to claim 1 , wherein at least 80% of the protuberances have mean diameters of from 40 to 380 nm.
6. The substrate according to claim 1 , wherein the protuberances comprise at least one member selected from the group consisting of: a layer of a material containing one or more oxidation or nitridation products, a layer formed by magnetic-field-assisted cathodic sputtering, a layer formed by plasma magnetron, a layer formed by plasma CVD, a layer formed by atmospheric CVD, a layer formed by powder and liquid pyrolysis, a layer formed by a polymerization process, a layer formed by a cross-linking process, a layer formed by a sol-gel type technique.
7. The substrate according to claim 1 , wherein:
a light transmission of the substrate is at least 80%; and
a haze of the substrate is 5% or less.
8. The substrate according to claim 1 , wherein the substrate is hydrophobic/oleophobic.
9. The substrate according to claim 8 , wherein the substrate comprises, at its outer surface, at least one member selected from the group consisting of:
a) compounds obtained in particular by a vacuum technique, by evaporation, sputtering, sol-gel, CVD or similar technique;
b) silicones; and
c) compounds of the formulas (I) and (II):
R p′ SiX 4−p′ (II)
in which:
m=0 to 15;
n=1 to 5;
p=0, 1 or 2;
R is a straight-chain or branched alkyl group or a hydrogen atom;
X is a hydrolysable. group such as a halo, alkoxy, acetoxy, acyloxy, amino or NCO group; and
p′=0, 1, 2 or 3.
10. The substrate according to claim 1 , wherein the substrate is hydrophilic/olephilic.
11. The substrate according to claim 1 , wherein the substrate has dirt-repelling properties.
12. The substrate according to claim 1 , wherein the substrate has antireflective properties.
13. The substrate according to claim 1 , wherein the substrate is electrically conductive.
14. A glazing for a ground transportation vehicle, a seagoing transportation vehicle, an airborne transportation vehicle, a building, an element of interior decoration, an element of exterior decoration, street furniture or electrical appliances, comprising:
the substrate according to claim 1 .
15. A reactor, comprising the substrate according to claim 1 , wherein:
the substrate includes cavities having diameters of between 0.1 and 500 nm, and
the reactor is a chemical reactor or a biochemical reactor.
16. A substrate, comprising:
a layer comprising a material selected from the group consisting of glass, silica and a polymeric material, wherein:
at least a portion of an outer surface of the layer has a geometry of a sheet provided with irregular protuberances;
at least 80% of the protuberances have heights of between 40 and 250 nm and mean diameters of between 1 and 500 nm;
at least 80% of adjacent protuberances are separated by a distance of between 1 and 500 nm;
the protuberances are obtained by etching a precursor layer through a mask; and
the protuberances have at least one shape selected from the group consisting of frustums of cones, cylinders, and columns.
17. The substrate of claim 16 , wherein:
a drop of water deposited on the substrate has a advancing angle of at least 160° and a receding angle of at least 120°; and
a difference between the advancing angle and the receding angle is less than 43°.