ANTIREFLECTIVE, SCRATCH-RESISTANT GLASS SUBSTRATE AND METHOD FOR MANUFACTURING THE SAME

Abstract

The invention concerns a method for manufacturing scratch-resistant antireflective glass substrates by ion implantation, comprising ionizing a source gas of N.sub.2 so as to form a mixture of single charge and multicharge ions of N, forming a beam of single charge and multicharge ions of N, by accelerating with an acceleration voltage comprised between 20 kV and 30 kV and an ion dosage comprised between 510.sup.16 ions/cm.sup.2 and 10.sup.17 ions/cm.sup.2. The invention further concerns scratch-resistant antireflective glass substrates comprising an area treated by ion implantation with a mixture of simple charge and multicharge ions according to this method.

Claims

1. A method for producing an antireflective, scratch-resistant glass substrate, the method comprising: a) providing a N.sub.2 source gas, b) ionizing the source gas so as to form a mixture of single charge ions and multicharge ions of N, c) accelerating the mixture of single charge ions and multicharge ions of N with an acceleration voltage so as to form a beam of single charge ions and multicharge ions, wherein the acceleration voltage is comprised between 20 kV and 30 kV and the ion dosage is comprised between 510.sup.16 ions/cm.sup.2 and 10.sup.17 ions/cm.sup.2, d) providing a glass substrate, and e) positioning the glass substrate in the trajectory of the beam of single charge and multicharge ions.

2. The method for producing an antireflective, scratch-resistant glass substrate according to claim 1, wherein the acceleration voltage is comprised between 22 kV and 28 kV and the ion dosage is comprised between 610.sup.16 ions/cm.sup.2 and 910.sup.16 ions/cm.sup.2.

3. The method for producing an antireflective, scratch-resistant glass substrate according to claim 2, wherein the acceleration voltage is comprised between 22 kV and 26 kV and the ion dosage is comprised between 810.sup.16 ions/cm.sup.2 and 910.sup.16 ions/cm.sup.2.

4. The method for producing an antireflective, scratch-resistant glass substrate according to claim 1, wherein the glass substrate has the following composition ranges expressed as weight percentage of the total weight of the glass: TABLE-US-00008 SiO.sub.2 35-85%, Al.sub.2O.sub.3 0-30%, P.sub.2O.sub.5 0-20%, B.sub.2O.sub.3 0-20%, Na.sub.2O 0-25%, CaO 0-20%, MgO 0-20%, K.sub.2O 0-20%, and BaO 0-20%.

5. The method for producing an antireflective, scratch-resistant glass substrate according to claim 4, wherein the glass substrate is selected from the group consisting of a soda-lime glass sheet, a borosilicate glass sheet, and an aluminosilicate glass sheet.

6. A method, comprising employing a mixture of single charge and multicharge ions of N to decrease the reflectance of a glass substrate and at the same time to maintain or increase the scratch resistance of the glass substrate, the mixture of single charge and multicharge ions of N being implanted in the glass substrate with a dosage and an acceleration voltage effective to decrease the reflectance of the glass substrate and at the same time to obtain a scratch resistance in terms of critical load comprised between 100% and 135% of the scratch resistance in terms of critical load of the untreated glass substrate.

7. The method according to claim 6, wherein the mixture of single charge and multicharge ions is being implanted in the glass substrate with a dosage and acceleration voltage effective to reduce the reflectance of the glass substrate to at most 6.5%.

8. The method according to claim 7, wherein the mixture of single charge and multicharge ions is being implanted in the glass substrate with a dosage and acceleration voltage effective to reduce the reflectance of the glass substrate to at most 6%.

9. The method according to claim 8, wherein the mixture of single charge and multicharge ions is being implanted in the glass substrate with a dosage and acceleration voltage effective to reduce the reflectance of the glass substrate to at most 5%.

10. The method according to claim 6, wherein the mixture of single charge and multicharge ions is being implanted in the glass substrate with a dosage and acceleration voltage effective to obtain a scratch resistance in terms of critical load comprised between 105% and 135% of the scratch resistance in terms of critical load of the untreated glass substrate.

11. The method according to claim 6, wherein the acceleration voltage is comprised between 20 kV and 30 kV and the ion dosage is comprised between 510.sup.16 ions/cm.sup.2 and 10.sup.17 ions/cm.sup.2.

12. An antireflective, scratch-resistant glass substrate produced by a method according to claim 1.

13. A monolithic glazing, laminated glazing or multiple glazing with interposed gas layer, comprising an antireflective, scratch-resistant glass substrate according to claim 12.

14. The glazing of claim 13, further comprising sun-shielding, heat-absorbing, anti-ultraviolet, antistatic, low-emissive, heating, anti-soiling, security, burglar proof, sound proofing, fire protection, anti-mist, water-repellant, anti-bacterial or mirror means.

15. The glazing of claim 13, wherein said antireflective, scratch-resistant glass substrate is frosted, printed or screen process printed.

16. The glazing of claim 13, wherein said substrate is tinted, tempered, reinforced, bent, folded or ultraviolet filtering.

17. The glazing of claim 13, comprising a laminated structure comprising a polymer type assembly sheet interposed between the antireflective, scratch-resistant glass substrate, with the ion implantation treated surface facing away from the polymer assembly sheet, and another glass substrate.

18. The glazing of claim 17, wherein said glazing is a car windshield.

Description

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0064] The ion implantation examples were prepared according to the various parameters detailed in the tables below using an RCE ion source for generating a beam of single charge and multicharge ions. The ion source used was a Hardion+RCE ion source from Quertech Ingnierie S.A.

[0065] All samples had a size of 1010 cm.sup.2 and were treated on the entire surface by displacing the glass substrate through the ion beam at a speed between 20 and 30 mm/s.

[0066] The temperature of the area of the glass substrate being treated was kept at a temperature less than or equal to the glass transition temperature of the glass substrate.

[0067] For all examples the implantation was performed in a vacuum chamber at a pressure of 10.sup.6 mbar.

[0068] Using a RCE ion source, ions of N were implanted in 4 mm thick regular clear soda-lime glass (E1-E4, C1-C10) and alumino-silicate glass substrates (E5-E11, C11-C12). Alumino-silicate glass substrates E9 to E12 and C12 were chemically tempered before ion implantation. The key implantation parameters, reflectance and scratch resistance measurements can be found in the tables below.

TABLE-US-00005 TABLE 4 acceleration light critical load critical glass voltage ion dosage reflectance with 100 m tip load reference substrate [kV] [ions/cm.sup.2] [%, D65, 2] [N] increase E1 Sodalime 20 6 10.sup.16 6.14 6.7 7% E2 Sodalime 20 7 10.sup.16 5.47 6.5 3% E3 Sodalime 20 8 10.sup.16 5.67 6.3 0% E4 Sodalime 20 9 10.sup.16 4.99 6.2 0% C1 Sodalime 0 0 7.9 6.3 C2 Sodalime 35 1 10.sup.17 6.37 5.0 C3 Sodalime 25 1 10.sup.17 5.5 4.4 C4 Sodalime 15 1 10.sup.17 5.5 4.8 C5 Sodalime 35 7.5 10.sup.15 7.9 7.3 C6 Sodalime 25 7.5 10.sup.15 7.9 7.5 C7 Sodalime 15 7.5 10.sup.15 7.9 7.6 C8 Sodalime 35 5 10.sup.16 7.4 8.0 C9 Sodalime 25 5 10.sup.16 7.9 7.7 C10 Sodalime 15 5 10.sup.16 7.8 7.6

[0069] As can be seen from table 4, examples E1 to E4 according to the present invention, treatment of the sodalime glass samples with an ion beam comprising a mixture of single charge and multicharge ions of N, accelerated with the same specific acceleration voltage and at such specific dosage, applied to a glass substrate, leads to a reduced reflectance and at the same time to an unmodified or even increased scratch resistance, when compared to the untreated sodalime glass sample C1. Comparative sodalime examples C2 to C4 lead to reduced reflectance but also to reduced scratch resistance. Comparative sodalime examples C5 to C10 lead to increased scratch resistance but not to any significant reduction of reflectance.

TABLE-US-00006 TABLE 5 acceleration light critical Critical voltage ion dosage reflectance load load reference glass substrate [kV] [ions/cm.sup.2] [%, D65, 2] [N] increase E5 Aluminosilicate 20 6 10.sup.16 5.85 10.2 24% E6 Aluminosilicate 20 7 10.sup.16 5.35 10.0 22% E7 Aluminosilicate 20 8 10.sup.16 5.13 9.9 21% E8 Aluminosilicate 20 9 10.sup.16 4.66 8.9 9% C11 Aluminosilicate 7.93 8.2

[0070] As can be seen from table 5, examples E5 to E8 according to the present invention, treatment of the aluminosilicate glass samples with an ion beam comprising a mixture of single charge and multicharge ions of N, accelerated with the same specific acceleration voltage and at such specific dosage, applied to a glass substrate, leads to a reduced reflectance and at the same time to an increased scratch resistance, when compared to the untreated aluminosilicate glass sample C11.

TABLE-US-00007 TABLE 6 acceleration light critical Critical voltage ion dosage reflectance load load reference glass substrate [kV] [ions/cm.sup.2] [%, D65, 2] [N] increase E9 Aluminosilicate 20 6 10.sup.16 6.15 9.7 18% E10 Aluminosilicate 20 7 10.sup.16 5.56 10.1 23% E11 Aluminosilicate 20 8 10.sup.16 5.48 10.6 29% E12 Aluminosilicate 20 9 10.sup.16 5.06 8.2 0% C12 Aluminosilicate 7.82 8.0

[0071] As can be seen from table 6, examples E9 to E12 according to the present invention, treatment of the chemically strengthened aluminosilicate glass samples with an ion beam comprising a mixture of single charge and multicharge ions of N, accelerated with the same specific acceleration voltage and at such specific dosage, applied to a glass substrate, leads to a reduced reflectance and at the same time to an unmodified or even increased scratch resistance, when compared to the untreated, chemically strengthened aluminosilicate glass sample C12. In the scratch resistance test, examples E9, E10, and E11 thus present a critical load increase of 18%, 23%, and 29% respectively, compared to the untreated glass substrate. On examples E9, E10, and E11 a scratch resistance in terms of critical load of 118%, 123%, and 129% respectively of the scratch resistance in terms of critical load of the untreated glass substrate was thus obtained.

[0072] Furthermore XPS measurements were made on the examples E1 to E12 of the present invention and it was found that the atomic concentration of implanted ions of N is below 8 atomic % throughout the implantation depth.