GLASS COMPOSITION, GLASS SHEET, AND VEHICLE WINDOW INCLUDING GLASS SHEET

Abstract

The present invention relates to an ultraviolet-shielding glass sheet including a glass composition based on soda-lime glass, the glass composition containing iron oxide and TiO.sub.2 as coloring components. The glass sheet has a thickness of 1 to 5 mm, and an ultraviolet transmittance (Tuv 380) as determined at the thickness according to ISO 9050:1990 is 1.5% or less.

Claims

1-16. (canceled)

17. An ultraviolet-shielding glass sheet comprising a glass composition based on soda-lime glass, the glass composition comprising iron oxide and TiO.sub.2 as coloring components, wherein the glass sheet has a thickness of 1 to 5 mm, and at the thickness, an ultraviolet transmittance (Tuv 380) as determined according to ISO 9050:1990 is 1.5% or less, an ultraviolet transmittance (Tuv 400) as determined according to ISO 13837:2008 convention A is 5.0% or less, a visible transmittance (YA) as measured using CIE standard illuminant A according to JIS R 3106:1998 is 20 to 40%, and a solar transmittance (TG) as measured according to JIS R 3106:1998 is 10 to 45%, the glass composition comprises, as base composition: 65 to 85 wt % SiO.sub.2; 0 to 5 wt % B.sub.2O.sub.3; 0 to 5 wt % Al.sub.2O.sub.3; 0 to 20 wt % MgO; 0 to 20 wt % CaO; 10 to 20 wt % Na.sub.2O; 0 to 5 wt % K.sub.2O; and 0 to 0.5 wt % SO.sub.3, the glass composition comprises, as coloring components: 0.2 to 2.0 wt % TiO.sub.2; 0.2 to 2.0 wt % CeO.sub.2; 1.0 wt % or more and less than 2.0 wt % T-Fe.sub.2O.sub.3, where T-Fe.sub.2O.sub.3 represents total iron oxide calculated as Fe.sub.2O.sub.3; 50 to 150 wt. ppm cobalt oxide (CoO) calculated as CoO; 0 to 200 wt. ppm NiO; and 8 to 35 wt. ppm Se, a FeO ratio is 5 to 30%, the FeO ratio representing a weight ratio of FeO calculated as Fe.sub.2O.sub.3 to T-Fe.sub.2O.sub.3, the total content of TiO.sub.2 and CeO.sub.2 is 2 wt % or more, and a NiO/Se ratio is 0 to 15, the NiO/Se ratio representing a content ratio of NiO to Se.

18. The ultraviolet-shielding glass sheet according to claim 17, wherein the base composition of the glass composition includes: 65 to 71 wt % SiO.sub.2; 0 to 5 wt % B.sub.2O.sub.3; 1 to 3 wt % Al.sub.2O.sub.3; 3 to 10 wt % MgO; 5 to 15 wt % CaO; 10 to 15 wt % Na.sub.2O; 0.5 to 2 wt % K.sub.2O; and 0 to 0.5 wt % SO.sub.3.

19. The ultraviolet-shielding glass sheet according to claim 17, wherein the coloring components of the glass composition comprise: 1.2 wt % or more and 1.8 wt % or less T-Fe.sub.2O.sub.3, where T-Fe.sub.2O.sub.3 represents total iron oxide calculated as Fe.sub.2O.sub.3.

20. The ultraviolet-shielding glass sheet according to claim 17, wherein the coloring components of the glass composition comprise: 0.3 to 1.8 wt % TiO.sub.2.

21. The ultraviolet-shielding glass sheet according to claim 17, wherein the coloring components of the glass composition, as calculated per cm.sup.2 of the glass sheet, comprise: 3 to 15 mg TiO.sub.2; 2 to 13 mg CeO.sub.2; 8 to 12 mg T-Fe.sub.2O.sub.3, where T-Fe.sub.2O.sub.3 represents total iron oxide calculated as Fe.sub.2O.sub.3; 37.5 to 225 μg cobalt oxide (CoO) calculated as CoO; 0 to 150 μg NiO; and 2.5 to 30 μg Se, and the total weight of TiO.sub.2 and CeO.sub.2 is 13 to 20 mg.

22. A strengthened glass sheet having a thickness of 1.0 to 3.5 mm, the strengthened glass sheet being obtained by thermally tempering the glass sheet according to claim 17.

23. A laminated glass sheet comprising a first glass sheet, an interlayer for glass lamination, and a second glass sheet, wherein at least one of the first and second glass sheets is the ultraviolet-shielding glass sheet according to claim 17.

24. A vehicle window pane comprising the strengthened glass sheet according to claim 22.

25. A vehicle window comprising the window pane according to claim 24, wherein when air mass 1.5 sunlight as defined in JIS C 8904:2011 is applied to the vehicle window from outside of a vehicle, an ultraviolet intensity at inside of the vehicle within a wavelength range up to 400 nm is 0.45 J.Math.s.sup.−1.Math.m.sup.−2 or less.

26. A vehicle window pane comprising the laminated glass sheet according to claim 23.

27. A vehicle window comprising the window pane according to claim 26, wherein when air mass 1.5 sunlight as defined in JIS C 8904:2011 is applied to the vehicle window from outside of a vehicle, an ultraviolet intensity at inside of the vehicle within a wavelength range up to 400 nm is 0.45 J.Math.s.sup.−1.Math.m.sup.−2 or less.

Description

EXAMPLES

[0079] Hereinafter, the present invention will be described in more detail with reference to examples. The following examples as well as the foregoing description are given merely for the purpose of illustrating preferred embodiments of the present invention.

[0080] Glass material batches were obtained by blending silica sand, dolomite, limestone, soda ash, salt cake, potassium carbonate, carbon, iron oxide, titanium oxide, cerium oxide, cobalt oxide, nickel oxide, and selenium to give compositions of glass as shown in Tables 1 to 4. Each of these batches was melted by an electric furnace at 1450° C., left in place for 4 hours, and then cast on a stainless steel plate. The glass sheet thus obtained was left in an annealing furnace held at 650° C. for 30 minutes, after which the annealing furnace was turned off to slowly cool the glass sheet to room temperature in the furnace. The rate of cooling from 650 to 550° C. in this annealing was about 0.1° C./sec. The resulting annealed glass sheet was ground to a predetermined thickness.

[0081] Next, each annealed glass sheet was subjected to thermal tempering. The thermal tempering was carried out as follows: The glass sheet was left in an electric furnace set at 700° C. for 180 seconds, after which the glass sheet was taken out of the electric furnace and quenched by exposing the glass sheet to blow of air at ordinary temperature. The rate of cooling from 650 to 550° C. in this quenching was 80 to 100° C./sec. The resulting strengthened glass sheet had a surface compressive stress ranging from 90 to 110 MPa.

[0082] For each of the glass sheets (annealed glass sheets and strengthened glass sheets), the following characteristic indices were measured: visible transmittance (YA) as measured using CIE standard illuminant A; total solar energy transmittance (TG); ultraviolet transmittances (Tuv 380 and Tuv 400) as determined according to ISO; dominant wavelength (DW) as measured using CIE standard illuminant C; excitation purity (Pe); and chromaticity (a*, b*) in the L*a*b* color system. The characteristic indices measured are shown in Table 2 and Table 4. In the tables, the total content is not 100% for some cases, which is due to the difference in the number of significant figures and rounding off.

[0083] (Composition Analysis)

[0084] The components of glass samples obtained were quantified by fluorescent X-ray analysis and chemical analysis. The results are shown in Table 1 and Table 3.

[0085] The properties of the annealed glass sheets will be discussed first. In Comparative Example 1, where CeO.sub.2 was not contained, the Tuv 380 was 1.6% even at a thickness of 4 mm, and a Tuv 380 of 1.5% or more was not achieved at any thickness in the range of 1.0 to 3.5 mm.

[0086] By contrast, in Examples 1 to 13, 20, 21, and 23 to 25, both a Tuv 380 of 1.0% or less and a YA of 20 to 30% were successfully achieved at thicknesses in the range of 2.5 to 3.5 mm. Additionally, in Examples 1 to 13, 20, 21, and 23 to 25, a Tuv 400 of 5.0% or less was successfully achieved as well. In particular, in Examples 6, 7, 23, and 25, the Tuv 380 was successfully reduced to 0.6% or less, despite a thickness of 2.5 mm. Furthermore, in Examples 6, 7, 23, and 25, the Tuv 400 was successfully reduced to 3.0% or less.

[0087] In Examples 6, 10, and 13, where the thicknesses of the glass sheets were 2.5 mm, 3.5 mm, and 2.8 mm, respectively, both the Tuv 380 and the Tuv 400 were 1.0% or less, which demonstrates that very high ultraviolet-shielding ability was exhibited.

[0088] In all of Examples 10 to 25, the thermal tempering successfully yielded values of Tuv 380 lower than those of the annealed glass sheets without causing a significant change in YA; specifically, a Tuv 380 of 1.5% or less was successfully obtained at thicknesses in the range of 2.5 to 3.5 mm. In Examples 1 to 13, 16, 18, and 20 to 25, a Tuv 400 of 5.0% or less was successfully achieved as well. In particular, in Examples 10 to 13, the Tuv 400 was successfully reduced to 2.0% or less. In Examples 10, 12, and 13, the Tuv 400 was successfully reduced to 1.0% or less.

[0089] When 3.5-mm-thick annealed glass sheets and 3.5-mm-thick thermally-tempered strengthened glass sheets are obtained using the glass compositions according to Examples 23 and 25, the annealed glass sheets have a Tuv 400 of 0.8%, and the thermally-tempered strengthened glass sheets have a Tuv 400 of 0.7%. That is, the strengthened glass sheet of the present invention can exhibit very high ultraviolet-shielding performance demonstrated by an ultraviolet transmittance of 1.0% or less, in either case of using Tuv 380 or Tuv 400 as the measure of the ultraviolet transmittance.

[0090] It can be expected, from the behaviors of the thermally-tempered strengthened glass sheets according to Examples 10 to 25, that the Tuv 380 and Tuv 400 of the glass sheets according to Examples 1 to 9 can be decreased by thermal tempering without a significant change in YA. In particular, it can be expected that both the Tuv 380 and the Tuv 400 can be reduced to 1.0% or less in Examples 1, 3 to 6, 8, and 9.

TABLE-US-00001 TABLE 1 Composition of glass Examples wt % 1 2 3 4 5 6 7 8 9 10 11 12 13 SiO.sub.2 67.4 69.2 69.1 69.4 69.2 68.7 67.5 67.7 67.3 69.1 69.1 68.9 68.6 Al.sub.2O.sub.3 1.72 1.41 1.40 1.41 1.41 1.41 1.72 1.72 1.71 1.47 1.49 1.57 1.56 MgO 4.28 3.41 3.41 3.42 3.41 3.13 4.28 4.26 4.27 3.19 3.20 3.19 3.18 CaO 8.77 7.52 7.51 7.54 7.52 7.50 4.28 8.73 8.76 7.10 7.15 7.14 7.07 Na.sub.2O 12.93 13.54 13.52 13.56 13.54 13.47 12.94 13.03 12.91 13.40 13.30 13.40 13.30 K.sub.2O 1.14 0.93 0.93 0.93 0.93 0.94 1.14 1.14 1.14 0.79 0.80 0.84 0.86 Fe.sub.2O.sub.3 2.31 2.20 2.20 2.10 2.15 2.90 2.50 2.30 2.30 2.46 2.59 2.68 2.79 ferrous % 21.0 23.1 25.2 25.4 27.6 22.8 24.4 23.5 23.3 21.9 22.2 22.5 22.1 SO.sub.3 0.17 0.18 0.18 0.17 0.16 0.17 0.17 0.17 0.17 0.25 0.24 0.23 0.23 CeO.sub.2 0 0 0 0 0 0 0 0 0 0 0 0 0 TiO.sub.2 1.49 1.60 1.70 1.50 1.60 1.80 1.00 1.00 1.40 1.84 1.80 1.85 1.83 CoO (wt. ppm) 155 95 95 95 95 95 140 110 50 105 105 95 95 NiO (wt. ppm) 0 0 0 0 0 0 0 0 0 0 0 0 0 Se (wt. ppm) 0 0 0 0 0 0 0 0 0 0 0 0 0 TiO.sub.2 + CeO.sub.2 1.49 1.60 1.70 1.50 1.60 1.80 1.00 1.00 1.40 1.84 1.80 1.85 1.83 Fe.sub.2O.sub.3 + TiO.sub.2 3.80 3.80 3.90 3.60 3.75 4.70 3.50 3.30 3.70 4.30 4.39 4.53 4.62 Fe.sub.2O.sub.3 + TiO.sub.2 + CeO.sub.2 3.80 3.80 3.90 3.60 3.75 4.70 3.50 3.30 3.70 4.30 4.39 4.53 4.62 NiO/Se — — — — — — — — — — — — — Fe.sub.2O.sub.3/CoO 149 232 232 221 226 305 179 209 460 234 247 282 294 density g/cm.sup.3 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57

TABLE-US-00002 TABLE 2 Amounts of coloring Examples components per unit area 1 2 3 4 5 6 7 8 9 10 11 12 13 Thickness (mm) 3.5 3.5 3.5 3.5 3.5 2.5 2.5 3.5 3.5 3.5 2.8 2.8 2.8 Fe.sub.2O.sub.3 (mg/cm.sup.2) 20.8 19.8 19.8 18.9 19.3 18.6 16.1 20.7 20.7 22.1 18.6 19.0 20.1 CeO.sub.2 (mg/cm.sup.2) 0 0 0 0 0 0 0 0 0 0 0 0 0 TiO.sub.2 (mg/cm.sup.2) 13.4 14.4 15.3 13.5 14.4 11.6 6.4 9.0 12.6 16.6 12.9 13.1 13.2 CoO (μg/cm2) 139 85 85 85 85 61 90 99 45 94 75 67 68 NiO (μg/cm.sup.2) 0 0 0 0 0 0 0 0 0 0 0 0 0 Se (μg/cm.sup.2) 0 0 0 0 0 0 0 0 0 0 0 0 0 TiO.sub.2 + CeO.sub.2 13.4 14.4 15.3 13.5 14.4 11.6 6.4 9.0 12.6 16.6 12.9 13.1 13.2 Annealed glass sheet YA (%) 24.0 29.4 26.4 28.7 25.6 24.5 29.3 24.7 30.3 26.1 31.2 30.0 28.0 TG.sub.2500 (%) 13.4 14.7 12.7 14.0 11.8 13.0 16.6 12.5 14.0 12.7 16.3 15.4 14.2 Tuv.sub.380 (%) 0.15 0.28 0.08 0.30 0.19 0.30 0.38 0.13 0.10 0.11 0.25 0.20 0.13 Tuv.sub.400 (%) 1.1 1.7 1.1 1.8 1.2 0.8 2.0 1.1 0.9 0.9 1.5 1.3 1.0 DW (nm) 556.7 558.3 561.0 556.9 558.9 568.5 557.4 558.3 565.0 562.7 564.3 564.8 565.4 Pe (%) 18.6 20.2 25.6 19.1 23.2 38.1 16.6 20.5 32.4 28.4 25.8 27.3 29.8 % T.sub.1500 — — 9.56 — — — — — — 10.0 14.0 13.2 12.3 a* −15.3 −15.5 −15.6 −15.8 −16.2 — — −15.5 −16.4 −15.1 −13.7 −13.7 −13.6 b* 14.7 16.6 19.6 15.8 18.1 — — 16.1 25.8 21.4 20.6 21.4 22.6 Thermally-tempered strengthened glass sheet YA (%) — — — — — — — — — 26.2 31.3 30.1 28.1 TG.sub.2500 (%) — — — — — — — — — 12.8 16.4 15.5 14.3 Tuv.sub.380 (%) — — — — — — — — — 0.06 0.14 0.11 0.074 Tuv.sub.400 (%) — — — — — — — — — 0.7 1.2 1.0 0.7 DW (nm) — — — — — — — — — 563.9 565.3 565.7 566.3 Pe (%) — — — — — — — — — 31.2 28.2 29.8 32.6 % T.sub.1500 — — — — — — — — — 9.3 13.2 12.4 11.4 a* — — — — — — — — — −14.9 −13.6 −13.6 −13.5 b* — — — — — — — — — 23.2 22.4 23.2 24.5

TABLE-US-00003 TABLE 3 Compar- ative Composition of glass Examples Example wt % 14 15 16 17 18 19 20 21 22 23 24 25 1 SiO.sub.2 69.4 69.4 69.5 69.4 69.3 69.2 69.2 69.4 66.8 65.1 67.3 65.7 69.0 Al.sub.2O.sub.3 1.49 1.49 1.49 1.48 1.48 1.48 1.48 1.48 1.70 1.84 1.71 1.86 1.6 MgO 3.74 3.74 3.74 3.40 3.73 3.73 3.72 3.73 4.33 4.70 4.32 4.70 3.6 CaO 7.66 7.66 7.67 7.66 7.65 7.63 7.63 7.65 9.04 9.82 8.85 9.62 8.4 Na.sub.2O 13.40 13.40 13.38 13.36 13.34 13.32 13.31 13.35 13.07 13.08 13.05 12.98 13.1 K.sub.2O 0.98 0.98 0.98 0.98 0.98 0.98 0.98 0.98 1.13 1.22 1.14 1.24 0.9 Fe.sub.2O.sub.3 1.30 1.30 1.33 1.25 1.28 1.31 1.46 1.46 1.45 1.57 1.45 1.58 1.40 ferrous % 6.8 9.5 23.0 24.7 22.0 22.8 19.4 25.7 22.0 21.0 28.1 29.0 30 CeO.sub.2 1.40 1.40 1.20 1.24 1.24 1.21 1.45 0.44 1.20 1.30 0.40 0.44 0 TiO.sub.2 0.45 0.45 0.50 0.64 0.77 0.91 0.82 1.33 1.10 1.19 1.60 1.74 1.6 CoO (wt. ppm) 250 250 195 195 205 203 182 205 220 239 240 261 115 NiO (wt. ppm) 0 0 147 149 148 146 88 89 100 109 100 109 0 Se (wt. ppm) 30 30 11 12 14 13 15 9 11 12 12 13 2 TiO.sub.2 + CeO.sub.2 1.85 1.85 1.70 1.88 2.01 2.12 2.27 1.77 2.30 2.49 2.00 2.18 1.60 Fe.sub.2O.sub.3 + TiO.sub.2 1.75 1.75 1.83 1.89 2.05 2.22 2.28 2.79 2.55 2.77 3.05 3.32 3.00 Fe.sub.2O.sub.3 + TiO.sub.2 + CeO.sub.2 3.15 3.15 3.03 3.13 3.29 3.43 3.73 3.23 3.75 4.07 3.45 3.75 3.00 NiO/Se 0 0 13.4 12.4 10.6 11.2 5.9 9.9 9.1 9.1 8.3 8.4 0 Fe.sub.2O.sub.3/CoO 52 52 68 64 62 65 80 71 66 66 60 60 122 density g/cm.sup.3 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.57 2.58 2.60 2.55 2.55 2.57

TABLE-US-00004 TABLE 4 Compar- Amounts of coloring ative components per unit Examples Example area 14 15 16 17 18 19 20 21 22 23 24 25 1 Thickness (mm) 3.5 3.0 3.5 3.5 3.5 3.0 3.0 3.5 2.5 2.5 3.0 2.5 4.0 Fe.sub.2O.sub.3 (mg/cm.sup.2) 11.7 10.0 12.0 11.2 11.5 10.1 11.3 13.1 9.4 10.3 11.1 10.0 14.4 CeO.sub.2 (mg/cm.sup.2) 12.6 10.8 10.8 11.2 11.2 9.3 11.2 4.0 7.7 8.5 3.1 2.8 0 TiO.sub.2 (μg/cm.sup.2) 4.0 3.5 4.5 5.8 6.9 7.0 6.3 12.0 7.1 7.8 12.2 11.1 16.5 CoO (μg/cm.sup.2) 225 193 175 175 184 157 140 184 142 156 184 166 118 NiO (μg/cm.sup.2) 0 0 132.3 134.1 133.2 112.6 67.9 80.1 64.5 71.1 76.5 69.5 0 Se (μg/cm.sup.2) 27.0 23.1 9.9 10.8 12.6 10.0 11.6 8.1 7.1 7.8 9.2 8.3 2.1 TiO.sub.2 + CeO.sub.2 16.6 14.3 15.3 16.9 18.1 16.4 17.5 15.9 14.8 16.3 15.3 13.9 16.5 Annealed glass sheet YA (%) 29.6 25.8 21.4 22.4 22.0 25.6 26.2 21.4 28.8 24.3 22.0 22.4 28.0 TG.sub.2500 (%) 44.2 37.0 19.1 19.4 20.6 23.7 24.8 16.1 26.8 24.1 17.3 18.2 16.1 Tuv.sub.380 (%) 1.09 1.13 1.09 1.20 1.15 1.38 1.04 0.86 1.05 0.43 0.75 0.57 1.6 Tuv.sub.400 (%) 6.1 7.5 4.8 5.2 4.9 5.5 4.6 3.6 4.6 2.4 3.7 2.5 — DW (nm) 485.8 494.3 543.9 531.5 545.2 556.7 567.9 547.6 569.4 572.5 558.5 567.8 525 Pe (%) 11.2 3.4 5.3 4.0 5.2 7.4 13.3 7.8 15.6 24.7 11.9 20.6 9.8 % T.sub.1500 54.7 48.0 23.1 22.4 25.1 28.9 31.1 17.7 34.4 33.8 20.7 23.6 — a* −6.4 −4.1 −7.3 −7.7 −6.9 −6.6 −4.9 −9.5 −4.9 −3.9 −8.9 −7.1 — b* −6.4 −0.6 4.5 3.7 4.4 6.1 9.8 6.5 11.6 16.7 9.1 14.3 — Thermally-tempered strengthened glass sheet YA (%) 31.4 30.0 21.4 22.4 21.8 25.6 26.7 21.5 29.3 24.9 22.3 23.1 — TG.sub.2500 (%) 44.0 38.1 19.2 19.6 20.7 23.9 25.0 16.4 27.3 24.4 17.6 19.0 — Tuv.sub.380 (%) 0.68 0.96 0.73 0.84 0.79 1.00 0.75 0.60 0.76 0.30 0.53 0.45 — Tuv.sub.400 (%) 5.0 7.6 3.9 4.3 4.1 4.7 3.9 3.0 3.9 2.0 2.7 2.0 — DW (nm) 486.6 487.6 548.1 538.7 549.9 558.2 567.5 552.0 569.1 572.0 560.4 568.1 — Pe (%) 12.7 9.9 6.0 4.6 5.9 7.9 13.3 9.0 — 24.1 12.9 — — % T.sub.1500 52.2 45.2 21.6 21.2 23.6 27.3 29.4 16.5 32.7 31.6 19.3 22.4 — a* −8.4 −7.1 −7.2 −7.5 −6.7 −6.5 −5.2 −9.3 −5.1 −4.4 −8.7 −6.9 — b* −6.9 −4.9 5.0 4.2 4.9 6.4 9.9 7.3 11.6 16.5 9.7 14.3 —

INDUSTRIAL APPLICABILITY

[0091] A glass sheet formed from the glass composition according to the present invention has a thickness of 1.0 to 3.5 mm and has both a moderate visible transmittance YA which ranges from 20 to 35% and a very low ultraviolet transmittance Tuv 380 which is 1.5% or less as determined according to ISO 9050:1990. This glass sheet is preferably a strengthened glass sheet, and is suitable for use in members that are desirably capable of substantially blocking transmission of ultraviolet light, such as window panes for vehicles and buildings, in particular rear side door windows, rear triangle windows, and rear windshields of automobiles.