NEUTRAL COLOR ANTIREFLECTIVE GLASS SUBSTRATE AND METHOD FOR MANUFACTURING THE SAME

Abstract

A method for manufacturing neutral color antireflective glass substrates by ion implantation, the method including ionizing a N.sub.2 source gas 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 A between 20 kV and 25 kV and setting the ion dosage at a value between 610.sup.16 ions/cm.sup.2 and 5.0010.sup.15A/kV+2.0010.sup.17 ions/cm.sup.2. A neutral color antireflective glass substrates including an area treated by ion implantation with a mixture of simple charge and multicharge ions according to the method.

Claims

1: A method for producing a neutral color antireflective glass substrate, the method comprising: a) providing a N.sub.2 source gas; b) ionizing the N.sub.2 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 A is comprised between 20 kV and 25 kV and the dosage D is comprised between 610.sup.16 ions/cm.sup.2 and 5.0010.sup.15A/kV+2.0010.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.

2: The method for producing a neutral color antireflective glass substrate according to claim 1, wherein the glass substrate comprises the following composition ranges expressed as weight percentage of the total weight of the glass: TABLE-US-00005 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 .sup.0-20%, and BaO 0-20%.

3: The method for producing a neutral color antireflective glass substrate according to claim 2, 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.

4: 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 keep the color in reflectance neutral, the mixture of single charge and multicharge ions being implanted in the glass substrate with an ion dosage and an acceleration voltage effective to reduce the reflectance of the glass substrate and at the same time keep the color in reflectance neutral.

5: The method according to claim 4, wherein the mixture of single charge and multicharge ions is being implanted in the glass substrate with an ion dosage and an acceleration voltage effective to reduce the reflectance of the glass substrate to at most 6.5% and at the same time keep the color in reflectance neutral such that 1a*1 and 1b*1.

6: The method according to claim 5, wherein the mixture of single charge and multicharge ions is being implanted in the glass substrate with an ion dosage and an acceleration voltage effective to reduce the reflectance of the glass substrate to at most 6.5% and at the same time keep the color in reflectance neutral such that 0.3a*0.3 and 0.3b*0.3.

7: The method according to claim 4, wherein the acceleration voltage A is comprised between 20 kV and 25 kV and the dosage D is comprised between 610.sup.16 ions/cm.sup.2 and 5.0010.sup.15A/kV+2.0010.sup.17 ions/cm.sup.2.

8: A neutral color antireflective glass substrate produced by a method according to claim 1.

9: A monolithic glazing, laminated glazing or multiple glazing with interposed gas layer, comprising a neutral color antireflective glass substrate according to claim 8.

10: The glazing of claim 9, 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, antibacterial or mirror means.

11: The glazing of claim 9, wherein said antireflective glass substrate is frosted, printed or screen process printed.

12: The glazing of claim 9, wherein said substrate is tinted, tempered, reinforced, bent, folded or ultraviolet filtering.

13: The glazing of claim 9, having a laminated structure comprising a polymer type assembly sheet interposed between the antireflective glass substrate, with the ion implantation treated surface facing away from the polymer assembly sheet, and another glass substrate.

14: The glazing of claim 13, wherein said glazing is a car windshield.

Description

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0058] 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.

[0059] 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.

[0060] 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.

[0061] For all examples the implantation was performed in a vacuum chamber at a pressure of 10.sup.6 mbar.

[0062] Ions of N were implanted in 4 mm regular clear 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 optical measurements can be found in the table below.

TABLE-US-00004 TABLE 4 a* b* acceleration ion Light reflectance reflectance Source glass voltage dosage reflectance [CIELAB, [CIELAB, reference gas substrate [kV] [ions/cm.sup.2] [%, D65, 2] D65, 10] D65, 10] E1 N.sub.2 Sodalime 25 6 10.sup.16 6.50 0.14 0.57 E2 N.sub.2 Sodalime 20 6 10.sup.16 6.14 0.22 0.40 E3 N.sub.2 Sodalime 20 8 10.sup.16 5.67 0.01 0.07 E4 N.sub.2 Sodalime 20 1 10.sup.17 6.50 0.25 0.03 E5 N.sub.2 Sodalime 25 7.5 10.sup.16 5.25 0.20 0.02 E6 N.sub.2 Alumino- 20 6 10.sup.16 5.85 0.17 0.96 silicate C1 N.sub.2 Sodalime 7.90 0.53 0.56 C2 N.sub.2 Sodalime 25 9 10.sup.16 5.15 0.33 1.19 C3 N.sub.2 Sodalime 25 2.5 10.sup.17 5.76 0.93 4.84 C4 N.sub.2 Sodalime 35 1 10.sup.17 6.37 1.12 5.16

[0063] As can be seen from examples E1 to E6 of the present invention, the chosen key parameters used for the ion implantation, where acceleration voltage A is comprised between 20 kV and 25 kV and the dosage D is comprised between 610.sup.16 ions/cm.sup.2 and 5.0010.sup.15A/kV+2.0010.sup.17 ions/cm.sup.2, lead on one hand to a reduced reflectance of at most 6.5%, at most 6.0% or even at most 5.5% and on the other hand the color in reflectance of these examples is neutral, that is 1a*1 and 1b*1. The key implantation parameters chosen for examples E3, E4, and E5 lead to a very neutral color in reflectance, that is 0.3a*0.3 and 0.3b*0.3.

[0064] Furthermore XPS measurements were made on the examples E1 to E6 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.