HEAT TREATABLE ANTIREFLECTIVE GLASS SUBSTRATE AND METHOD FOR MANUFACTURING THE SAME

Abstract

The invention concerns a method for manufacturing heat treatable antireflective glass substrates by ion implantation, comprising selecting a source gas of N.sub.2, O.sub.2, or Ar, ionizing the source gas so as to form a mixture of single charge and multicharge ions of Ar, N, or O, forming a beam of single charge and multicharge ions of Ar, N, or O by accelerating with an acceleration voltage comprised between 15 kV and 60 kV and setting the ion dosage at a value comprised between 7.510.sup.16 and 7.510.sup.17 ions/cm.sup.2. The invention further concerns heat treatable and heat treated 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 a heat treatable antireflective glass substrate comprising: a) providing at least one source gas selected from the group consisting of N.sub.2, O.sub.2, and Ar, b) ionizing the source gas so as to form a mixture of single charge ions and multicharge ions of N, O, and/or Ar, c) accelerating the mixture of single charge ions and multicharge ions of N, O, and/or Ar with an acceleration voltage so as to form a beam of single charge ions and multicharge ions of N, O, and/or Ar, wherein the acceleration voltage is between 15 kV and 60 kV and the ion dosage is between 7.510.sup.16 and 7.510.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 of N, O, and/or Ar.

2. The method for producing a heat treatable antireflective glass substrate according to claim 1, wherein the acceleration voltage is between 30 kV and 40 kV and the ion dosage is between 7.510.sup.16 and 510.sup.17 ions/cm.sup.2.

3. The method for producing a heat treatable antireflective glass substrate according to claim 2, wherein the acceleration voltage is between 30 kV and 40 kV and the ion dosage is between 7.510.sup.6 and 110.sup.17 ions/cm.sup.2.

4. The method for producing a heat treatable antireflective glass substrate according to claim 1 wherein the source gas is at least one selected from the group consisting of N.sub.2 and O.sub.2.

5. The method for producing a heat treatable antireflective glass substrate according to claim 1, wherein the glass substrate provided has the following composition ranges expressed as weight percentage of the total weight of the glass: TABLE-US-00007 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%.

6. The method for producing a heat treatable antireflective glass substrate according to claim 5, 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.

7. A method for producing a heat treated antireflective glass substrate comprising: a) providing at least one source gas selected from the group consisting of N.sub.2, O.sub.2, and Ar, b) ionizing the source gas so as to form a mixture of single charge ions and multicharge ions of N, O, and/or Ar, c) accelerating the mixture of single charge ions and multicharge ions of N, O, and/or Ar with an acceleration voltage so as to form a beam of single charge ions and multicharge ions, wherein the acceleration voltage is between 15 kV and 60 kV and the ion dosage is between 7.510.sup.16 and 7.510.sup.17 ions/cm.sup.2, d) providing a glass substrate, e) positioning the glass substrate in the trajectory of the beam of single charge and multicharge ions of N, O, and/or Ar, and f) subjecting the glass substrate to a heat treatment comprising thermal tempering, bending or annealing.

8. The method for producing a heat treated antireflective glass substrate according to claim 7 wherein the heat treatment comprises heating the glass substrate to a temperature higher than 560 C. in air for a period of 4 to 20 minutes.

9. The method for producing a heat treated antireflective glass substrate according to claim 7, wherein the acceleration voltage is between 30 kV and 40 kV and the ion dosage is between 7.510.sup.16 and 510.sup.17 ions/cm.sup.2.

10. The method for producing a heat treated antireflective glass substrate according to claim 9, wherein the acceleration voltage is between 30 kV and 40 kV and the ion dosage is between 7.510.sup.16 and 110.sup.17 ions/cm.sup.2.

11. The method for producing a heat treated antireflective glass substrate according to claim 7, wherein the source gas is at least one selected from the group consisting of N.sub.2 and O.sub.2.

12. The method for producing a heat treated antireflective glass substrate according to claim 7, wherein the glass substrate provided 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%.

13. The method for producing a heat treated antireflective glass substrate according to claim 12, 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.

14-20. (canceled)

21. A heat treatable antireflective glass substrate produced by the method according to claim 1.

22. A heat treated antireflective glass substrate produced by the method according to claim 7.

23. A monolithic glazing, laminated glazing or multiple glazing with interposed gas layer, comprising the heat treatable antireflective glass substrate according to claim 21.

24. The glazing of claim 23, 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.

25. The glazing of claim 23, wherein said antireflective glass substrate is frosted, printed or screen process printed.

26. The glazing of claim 23, wherein said substrate is tinted, tempered, reinforced, bent, folded or ultraviolet filtering.

27. The glazing of claim 23, having a laminated structure comprising a polymer assembly sheet interposed between the antireflective glass substrate, with an ion implantation treated surface facing away from the polymer assembly sheet, and another glass substrate.

28. The glazing of claim 27, wherein said glazing is a car windshield.

Description

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0079] 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.

[0080] All samples had a size of 1010cm.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.

[0081] The temperature of the area of the glass substrate being implanted was kept at a temperature less than or equal to the glass transition temperature of the glass substrate.

[0082] For all examples the implantation was performed in a vacuum chamber at a pressure of 10.sup.6 mbar.

[0083] Using the RCE ion source, ions of N and O were implanted in 4 mm thick regular dear soda-lime glass and alumino-silicate glass substrates. Before being implanted with the ion implantation method of the present invention the reflectance of the glass substrates was about 8%. The key implantation parameters, and measured reflectance measurements can be found in the tables below.

[0084] A heat treatment was performed on examples of the present invention by heating them in a static furnace at 670 C. for 4 minutes. These heat treatment parameters simulate the heat load of thermal tempering for glass substrates of 4 mm thickness.

TABLE-US-00006 TABLE 4 light reflectance light reflectance acceleration ion before heat after heat Source glass voltage dosage treatment treatment reference gas substrate [kV] [ions/cm.sup.2] [%, D65, 2] [%, D65, 2] E1 N.sub.2 Sodalime 35 1 10.sup.17 6.37 4.89 E2 N.sub.2 Sodalime 35 7.5 10.sup.16 5.96 4.61 E3 O.sub.2 Sodalime 35 1 10.sup.17 5.64 5.03

[0085] As can be seen from Table 4, examples E1, E2 and E3 of the present invention reach low reflectance not only before heat treatment but also after heat treatment. Most surprisingly they even show a further decreased light reflectance after heat treatment. Upon heat treatment, the reflectance of example E3 decreases by 0.61%, the reflectance of example E2 decreases by 0.47%, the reflectance of example E1 decreases by 1.12%.

[0086] Furthermore XPS measurements were made on the samples E1 to E3 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.