JPH08301632A - Brown contrast enhanced glass - Google Patents

Abstract

(57) [Summary] [Purpose] For brown glass, Hunter coordinates a, b,
Luminous transmittance,% T, ANSI Z80.3-1986 D ₆₅₀₀ (x,
y) and to provide the desired and / or required performance with respect to traffic signal transmission. [Constitution] SiO ₂ is 40 to 72, B ₂ O ₃ is 0 to 13 by weight%,
Al ₂ O ₃ 0.5 to 3, Li ₂ O 0 to 3, Na ₂ O 8 to 15, K ₂
O for 1 to 10, TiO ₂ for 4.2 to 10.2, CeO ₂ for 0.5 to
3.5, Nd ₂ O ₃ 5.0 to 16.5, Fe ₂ O ₃ 2.5 to 4.0, Co
O for 0.00 to 0.02, NiO for 0.06 to 0.33, ZnO for 0.0 to
7.0, Er ₂ O ₃ 0-2, Cr ₂ O ₃ 0.0-0.2, V ₂ O ₅
0.0-0.2, CuO 0.00-0.10, MnO ₂ 0.0-2.0,% T _{V, C} (1.8 mm) specified in ANSI Z80.3-1986 is 1
4 to 30, a is -0.1 to +6.0, b is +18.0 to + 26.0,%
T (380 nm; 1.8 mm) is 0.0,% T (400 nm; 1.
8mm) is ≤1.5 and D of ANSI Z80.3-1986
_A glass composition which complies with the ₆₅₀₀ (1.8 mm) and traffic signal (1.8 mm) standards, and in which the amount of Fe ⁺² is chosen to be low enough to achieve said traffic signal properties.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is useful in ophthalmic applications such as lenses for sunglasses, and is desirable and / or related to visual identification requirements such as appearance, visibility, and transmission of traffic signals. It relates to an improved contrast-enhancing glass having the required properties.

[0002]

BACKGROUND OF THE INVENTION For many applications it is desirable to enhance the contrast of a target with respect to background radiation. In addition, preferably the wavelength
Amount of UV radiation up to 380 nm, and in some cases, for example where UV radiation is particularly harmful, in order to achieve 0% transmission up to around 400 nm, through a given glass, eg sunglasses. Is often desired. While it has been possible in the past to obtain only one of these effects, and to some extent both effects together, nevertheless, especially in brown glass, particularly in the case of strictness such as traffic signal transmission. There is room for improvement when simultaneously meeting various requirements. Of course, for ophthalmic and / or visual applications, it is desirable that the glass be capable of providing tight lens correction (high power) and low density.

It is known that Nd ₂ O ₃ can provide contrast enhancement due to its natural absorption band combination in the visible region. For example, U.S. Pat.
No. 4,288,250, 4,521,524, 4,376,829
See Nos. 4,405,881 and 4,390,637.
Even in contrast-enhanced glass containing Nd, it is desirable that the radiation from the desired object maintain the true color of the object as it passes through it and that the image of the object is sharp. Given such properties, the glass would be most useful in flat or prescription lenses.

Neodymium has also been added to various glasses for various other purposes. For example, U.S. Patent No. 1,449,79
No. 3 (colored), No. 2,688,560 (colored), No. 3,457,182
No. (laser emission), No. 3,640,890 (laser emission)
And No. 4,093,468 (Glass Ceramics Coloring). In addition, in order to obtain the desired color in silicate glass, CeO ₂ , Sm ₂ O ₃ , Fe ₂ O ₃ , CoO, NiO, CuO,
It is known to add colorants such as Er ₂ O ₃ , MnO ₂ , V ₂ O ₅ , Cr ₂ O ₃ etc. in various combinations. CeO ₂ is also
Well known as a sunscreen. Many of the patents mentioned above as well as, for example, U.S. Pat.
See Nos. 3,672,919 and 3,960,754.
The ability of these colorants as well as TiO ₂ to absorb short wavelength radiation is also generally known. For example U.S. Pat.
See issue 1,524.

Some of the problems discussed above have been addressed by US Pat.
Although gray glass has been resolved in 896, it also reports first attempts and attempts to resolve such problems with brown glass have failed.
See Examples J, K and 22 thereof. As can be seen from col. 5, line 56 to col. 6, line 10, and in light of the properties listed for these three examples in col. 7 and col. And /
Or the required properties could not be achieved at the same time.

[0006] The present invention solves the above problems with brown glass and provides a pleasing appearance and color and especially a, b,
It provides the desired and / or required performance in terms of T _{v, c} , D ₆₅₀₀ (x, y),% T and traffic signal transmission (all defined below).

[0007]

SUMMARY OF THE INVENTION The present invention, in one aspect, is a glass composition that achieves the above-described properties, wherein the weight percent of the batch based, oxide weight percent SiO ₂ 40 to 72 B ₂ O ₃ 0 ~ 13 Al ₂ O ₃ 0.5 ~ 3 Li ₂ O 0 ~ 3 Na ₂ O 8 ~ 15 K ₂ O 1 ~ 10 TiO ₂ 4.2 ~ 10.2 CeO ₂ 0.5 ~ 3.5 Nd ₂ O ₃ 5.0 ~ 16.5 Fe ₂ O ₃ 2.5 〜 4.0 CoO 0.00 〜 0.02 NiO 0.06 〜 0.33 ZnO 0.0 〜 7.0 Er ₂ O ₃ 0 〜 2 Cr ₂ O ₃ 0.0 〜 0.2 V ₂ O ₅ 0.0 〜 0.2 CuO 0.00 〜 0.10 MnO ₂ 0.0 〜 2.0 、% T _{V , C} (1.8 mm thickness) 14 to 30 a −0.1 to +6.0 b +18.0 to + 26.0% T (380 nm; 1.8 mm thickness) 0.0% T (400 nm; 1.8 mm thickness) ≤ 1.5 And complies with the ANSI Z80.3-1986 (incorporated herein by reference in its entirety) D ₆₅₀₀ (1.8 mm thick) and traffic signal (1.8 mm thick) standards, and here, in particular Low enough to achieve "a" and D ₆₅₀₀ chromaticity values To the glass composition in which the amount of Fe ^{+2 in} the glass is chosen to be

Typically, such an amount of Fe ⁺² is less than about 4.5% of the amount of iron in the glass, more preferably less than 3%, less than 2% or even less than 1%. Let's do it. The percentage values here are defined in Example 28.

A more preferable aspect is that the glass composition has a weight percentage of oxides SiO ₂ 45 to 65 B ₂ O ₃ 0.5 to 5 Al ₂ O ₃ 0.5 to 2.5 Li ₂ O 0.0 to 2.7 Na ₂ O 8.5 to 15.0 K. ₂ O 1.0 to 8.5 TiO ₂ 5.2 to 9.2 CeO ₂ 1 to 3 Nd ₂ O ₃ 5.0 to 14 Fe ₂ O ₃ 2.6 to 3.7 CoO 0.00 to 0.017 NiO 0.10 to 0.25 ZnO 0.0 to 6.5 Er ₂ O ₃ 0 to 1.0 Cr ₂ O ₃ 0.00 to 0.17 V ₂ O ₅ 0.0 to 0.17 CuO 0.00 to 0.08 MnO ₂ 0.0 to 1.8,

Most preferably, the glass composition comprises an oxide weight percent SiO ₂ 48 to 60 B ₂ O ₃ 0.5 to 2.5 Al ₂ O ₃ 0.5 to 1.5 Li ₂ O 0.0 to 2.4 Na ₂ O 9 to 15 K. _{2 O 1.0 ~ 7.5 TiO 2 6} ~ 9 CeO 2 1.5 ~ 2.8 Nd 2 O 3 5.0 ~ 13.0 Fe 2 O 3 2.7 ~ 3.6 CoO 0.000~ 0.015 NiO 0.11 ~ 0.24 ZnO 0.0 ~ 6.0 Er 2 O 3 0.0 ~ 0.5 Cr 2 O ₃ 0.00 to 0.15 V ₂ O ₅ 0.0 to 0.15 CuO 0.00 to 0.07 MnO ₂ 0.0 to 1.4, and

Is the property of% T _{V, C} (1.8 mm thickness) 14 to 25 a -0.1 to +5.5 b +18.5 to +25.5?

Most preferably, it is% T _{V, C} (1.8 mm thickness) 15 to 24 a −0.1 to +4.5 b +19.0 to +25.0.

The above aspects of the invention maintain a low level of Fe ^{+2 in} the glass so that the desired properties are achieved, especially with regard to chromaticity values such as a, b, D ₆₅₀₀ , traffic signals, etc. Involves doing. This can be achieved by H ₂ or carbon other like during melting of the glass, reducing conditions and / or reducing agent to ensure that there is no. Preferably, the glass can be melted under at least slightly oxidizing conditions, for example by using nitrate as a metal compound batch component or by using any other oxidation method. For example, "Colour Gen
eration and Control in Glass ", Glass Science and T
echnology, 2, CR Bamford Elsevier Scientific Pub
See lishing Co., NY (1977), pp.77-87. In many cases, it will be sufficient to ensure that no reducing conditions are present.

The discovery of the importance of this Fe ⁺² content solves the problems faced in the attempt of US Pat. No. 5,190,896 and provides a desirable brown glass. Thus, in one aspect of the invention, the present inventor has
It was discovered that Example 22 of 896 contained 7% Fe ⁺² based on what was defined in Example 28, and therefore could not meet chromaticity specifications. By choosing the proper Fe ⁺² content according to the above definition, this aspect of the invention accordingly solves the problems of the prior art. See Examples A-C, 1 and 2 below.

In another aspect, the present invention is a glass composition that achieves the above-described properties, wherein the weight percent of batch basis is oxide weight percent SiO ₂ 40-72 B ₂ O ₃ 0-13 Al ₂ O ₃ 0.5 〜 3 Li ₂ O 0 〜 3 Na ₂ O 8 〜 15 K ₂ O 1 〜 10 TiO ₂ 4.2 〜 10.2 CeO ₂ 0.5 〜 3.5 Nd ₂ O ₃ 5.0 〜 16.5 Fe ₂ O ₃ 2.5 〜 4.0 CoO 0.0053 〜 0.02 NiO 0.06 〜 0.33 ZnO 0.0 〜 7.0 Er ₂ O ₃ 0 〜 2 Cr ₂ O ₃ 0.0 〜 0.2 V ₂ O ₅ 0.0 〜 0.2 CuO 0.00 〜 0.10 MnO ₂ 0.0 〜 2.0 including% T _{V, C} (1.8 mm Thickness) 14-30a-0.1- + 6.0b + 18.0- + 26.0% T (380 nm; 1.8 mm thickness) 0.0% T (400 nm; 1.8 mm thickness) ≤ 1.5 Z80.3-1986 of D ₆₅₀₀ (1.8 mm
Thickness) and traffic signal (1.8 mm thickness) specifications.

These glasses are described in US Pat. No. 5,190,896.
The above-mentioned problems of the prior art of U.S. Pat. No. 5,968,961 are used, for example, by using the cobalt content which is essential to maintain the chromaticity properties, whereby the desired chromaticity of the present invention is applied to the oxide composition of Example 22 of US Pat. To achieve a solution in a different way. See Examples A and 3 below. Once a certain amount of cobalt is included in the glasses of the present invention, it is expected that the effect will be relatively less dramatic with the further addition of cobalt. It is also desirable for these cobalt-containing glasses to also maintain lower levels of Fe ⁺² as described above.

In another preferred aspect, the glass composition comprises an oxide weight percent SiO ₂ 45 to 65 B ₂ O ₃ 0.5 to 5 Al ₂ O ₃ 0.5 to 2.5 Li ₂ O 0.0 to 2.7 Na ₂ O 8.5 to 15.0. K ₂ O 1.0 to 8.5 TiO ₂ 5.2 to 9.2 CeO ₂ 1 to 3 Nd ₂ O ₃ 5.0 to 14 Fe ₂ O ₃ 2.6 to 3.7 CoO 0.0053 to 0.017 NiO 0.10 to 0.25 ZnO 0.0 to 6.5 Er ₂ O ₃ 0.0 to 1.0 Cr ₂ O ₃ 0.00 to 0.17 V ₂ O ₅ 0.0 to 0.17 CuO 0.00 to 0.08 MnO ₂ 0.0 to 1.8,

Most preferably, the glass composition comprises oxide weight percent SiO ₂ 48 to 60 B ₂ O ₃ 0.5 to 2.5 Al ₂ O ₃ 0.5 to 1.5 Li ₂ O 0.0 to 2.4 Na ₂ O 9 to 15 K _{2. O 1.0 ~ 7.5 TiO 2 6 ~} 9 CeO 2 1.5 ~ 2.8 Nd 2 O 3 5.0 ~ 13.0 Fe 2 O 3 2.7 ~ 3.6 CoO 0.0053 ~ 0.015 NiO 0.11 ~ 0.24 ZnO 0.0 ~ 6.0 Er 2 O 3 0.0 ~ 0.5 Cr 2 O ₃ 0.00 to 0.15 V ₂ O ₅ 0.00 to 0.15 CuO 0.00 to 0.07 MnO ₂ 0.0 to 1.4, and

The property is% T _{V, C} (1.8 mm thickness) 14-25 a −0.1 to +5.5 b +18.5 to +25.5, or

Most preferably, it is% T _{V, C} (1.8 mm thickness) 15 to 24 a −0.1 to +4.5 b +19.0 to +25.0.

In yet another aspect of the invention, the amount of Fe ₂ O ₃ in the glass is such that, in the case of brown glass, Fe ₂ O ₃ is required to achieve the chromaticity characteristics required by the invention. U.S. Pat.No. 5, implying the need for a lower content
Despite the trends shown in 190,896, at least 2.
8% by weight.

A further advantage of the present invention is that the n of the glass is
High _e (green mercury ray, 546 nm) and low density of the glass. These properties are especially important for prescription lenses.

Furthermore, in addition to the components listed above, small amounts of conventional ROs such as CaO, MgO and ZnO in the glass of the present invention, for example 0 to 2% by weight, more preferably 0 to 1% by weight.
Alternatively, 0 to 0.5% by weight can be contained,
Most preferably it is essentially free of alkaline earth metal oxides. When included, these components improve the chemical resistance of the glass, but generally interfere with the chemical strengthening properties other than ZnO. Small amounts of these ingredients make a large difference in the color of the glass. ZrO ₂ can also be included in the same amount. At higher levels, the color properties are adversely affected.

With respect to UV attenuation, it is also possible to employ a conventional UV attenuating surface coating on the glass to attenuate the UV radiation as a whole, if desired.
However, a great advantage of the glasses of the invention is that they are highly UV-attenuated, optionally without a coating. The nature of such coatings and the methods of applying them or other coatings such as mirror coatings are conventional. "Coatings on Glass,"
Thin Films Science and Technology, 6, HK Pulker
Elsevier Science Publishing Co. Inc., NY, NY
checking ...

If the amount of TiO ₂ , CeO ₂ or Fe ₂ O ₃ is higher or lower than the predetermined composition tolerance, it will lead to undesired UV attenuation, transmission and / or color space. Fe ₂ O
_{If the 3} amount exceeds the allowable range, the chromaticity and transmittance requirements are not achieved. If the density is lower than the minimum, the chromaticity drops. If the CeO ₂ concentration is higher than specified, the desired chromaticity for D ₆₅₀₀ is not achieved. If the concentration charge is below the minimum, chromaticity and transparency are not achieved. If the TiO ₂ concentration is higher than the predetermined value, the color coordinate standard is adversely affected. If the TiO ₂ concentration is lower than specified, the 400 nm attenuation and chromaticity requirements are not achieved.

Nd ₂ O ₃ is the main contrast enhancing component. Amounts up to 5.0% by weight can have a detrimental effect on contrast enhancement, and amounts above 16.5% by weight are redundant for contrast enhancement purposes.

La ₂ O ₃ can be replaced on a per ion basis on the Nd ₂ O ₃ in the glasses of the invention. Thus, for any Nd ₂ O ₃ containing glass of the present invention, any amount exceeding the minimum amount of 5.0 wt% of the above Nd ₂ O
₃ also satisfies La ₂ O ₃ when a smaller amount of Nd ₂ O ₃ is satisfactory.
Can be replaced with, thus keeping this rare earth level in the composition constant.

SiO ₂ is, of course, the basic network former. B ₂ O ₃ is added to aid melting. Since the glass is preferably tank manufactured, B ₂ too high
The O ₃ content can lead to excessive elution of the refractory material in the tank, causing harmful content problems and significant tank wear.

Al ₂ O ₃ is included to improve the resistance it imparts to the glass. If the Al ₂ O ₃ content is too high, melting difficulties will occur. Alkali metal oxides increase the ease with which the glass melts. The amount of Na ₂ O is increased with respect to the amounts of Li ₂ O and K ₂ O in order to increase the chemical strengthening property. Too much K ₂ O can have a detrimental effect on this property. In addition, if the Li ₂ O content is too high,
It can lead to unacceptable crystallization of bulk glass.

The preferred colorants for brown glass are CoO 2 and NiO 2, as mentioned above. _{Cr 2 O 3, V 2 O} 5, MnO 2 , and other colorants, such as CuO is due desired as described above. The colorant Er ₂ O ₃ can be added to improve the contrast enhancement due to its selective absorption in specific visible spectral regions.

The amount of each component of the glass of the present invention can be changed within the predetermined range, for example, one or both end points of the range is incremented from the above end point by 0.
It can instead be defined by a narrower inclusive range, which varies by 01, 0.1, 0.5, etc. Surprisingly, all of these ingredients within the given amount require no more than routine experimentation with conventional tests to determine whether properties are as desired. It makes it possible to immediately achieve the desired UV properties and the desired chromaticity and transparency. Amounts and combinations can be varied to achieve exactly the desired shade.

The glasses of the present invention can be chemically strengthened or air cured using very well known procedures. They (for example molded, ground and polished) can likewise be employed as sunglasses lenses by standard attachment to suitable spectacle frames in a totally conventional manner.

The color characteristics referred to herein are the Hunter color coordinates a (or a _L ) which are related in a known manner to the conventional CIE system.
And b (or b _L ) are defined in a completely conventional manner (Color by Guenther Wyszecki and WS Stiles
Science, C. 1967. CIE and chromaticity coodinate
s, page 279 and especially L, a and b, see page 460). The a and b coordinates were chosen especially from an aesthetic point of view.

The luminous transmittance according to page 8 of ANSI Z80.3-1986 is the CIE (1931) colorimetric standard according to the corresponding coordinates of the distribution of the photopic luminosity of the observer and the standard It is a function of the spectral transmittance of the lens, weighted by the spectral intensity of source C. This transmission is here designated T _{V, C.}

The luminous transmittance (T _V ) (equivalent to T _{V, C} notation) of the lens is mathematically expressed as follows.

[0036]

[Equation 1]

The luminous transmittances specified above meet the requirements of the American National Standard for Fashion Eyeglass Applications for non-prescription ophthalmic sunglasses and general purpose sunglasses (ANSI standard Z80.3-1986 No. 15). Page).

In addition to the luminous transmittance, traffic signal recognition is
SI Z80.3-1986 is one of the important criteria that must be met in order to comply with the general purpose sunglasses application on page 15 (see ANSI Z80.3-1986 page 15 and page 16 Figure 1). reference).

The transmission characteristics associated with traffic signal recognition can be described as follows.

[Chromaticity Coordinates] The chromaticity coordinates x and y of a traffic signal and average sunlight (D65) when viewed through a lens are
It is expressed mathematically as follows.

[0041]

[Equation 2]

The values of X, Y and Z are determined as follows: (1) For traffic signals seen through the lens:

(Equation 3)

(2) Average sunlight (D6 seen through the lens)
For 5),

[Equation 4]

Where: τ (λ) = spectral transmittance of lens S _A (λ) = spectral intensity of standard light source A S _D65 (λ) = spectral intensity of standard light source D65 τ _sig (λ) = traffic signal filter ( Spectral transmittance of red, yellow and green)

[0045]

(Equation 5)

[Traffic signal transmittance] The traffic signal transmittance is C
The spectral transmittance of the lens weighted by the corresponding coordinates of the photopic luminous efficiency distribution of the IE (1931) standard observer, the spectral intensity of the standard light source A, and the appropriate traffic signal filters (red, yellow and green). ) Is a function of the spectral transmittance of.

The traffic signal transmittance (τ _sig ) of the lens is mathematically expressed as follows.

[0048]

(Equation 6)

Computer-calculated data for transmittance characteristics is given in Table 1 of ANSI Z80.3-1986. (Suitable reference data for Table 1 is given in Table 2 of ANSI Z80.3-1986.)

The given glass is ANSI Z80.3-1986 D
Compliance with the ₆₅₀₀ and traffic signal standards is determined by comparing the relevant x, y and T _sig (equal to τ _sig ) values measured according to the stated ANSI standard with the standard values given in the ANSI standard. By doing, you can make decisions on a daily basis.

When the glasses of the present invention are employed as contrast-enhancing spectacle lenses, such as sunglasses, they are preferably shaped into a shape suitable for use in a conventional manner, and conventionally a typical spectacle frame. Be combined. If the glass is to be used as a contrast enhancing filter in other applications, similar processing would be used with the desired shape combination.

The glass of the present invention can be formed into any desired shape using conventional molding methods well known in the glass industry. In light of the combination of the above ingredients,
The glass of the present invention is manufactured by Stroud's "Glass Technology", Vol.
29, No. 3, June 1988, pages 108-114, can be very well chemically strengthened using conventional techniques. Typically, for example, 99.5% by weight KNO ₃ and
Crown bath solutions of 0.5% by weight silicic acid at temperatures in the range of about 420 to 480 ° C. can be used for exchange times of, for example, 16 hours. Typically, the preferred exchange temperature is
It will be about 25 ° C. below the strain point of the glass. The determination of the optimum chemical strengthening layer thickness can be performed routinely. Typically, the acceptable thickness of the chemically strengthened layer is greater than 20 μm, more preferably about 50 μm, but can be smaller or larger. Typical surface compression values achievable in these glasses are about 1700-20
It is 00 nm / cm (birefringence).

The glasses according to the invention are prepared by using the usual batch components corresponding to the above-mentioned composition, in a suitable crucible, for example a platinum or ceramic crucible, for example at the melt temperature.
It can be routinely prepared by melting in the conventional manner at 1300 to 1450 ° C.

An example of typical properties of the glass of the present invention is as follows. [Physical properties] Density ^{(g / cm 3) 2.85 CTE} × 10 -7 ℃ -1 (20~300 ℃) 93 Tg (℃) 503 softening point (° C.) 650 [Optical properties] n _e 1.603 v _e 41.6 [Ultraviolet transmission characteristics]% T at 400 nm (1.8 mm thickness) 0.3% T at 380 nm (1.8 mm thickness) 0.0

Without further ado, the person skilled in the art is convinced that the above description can be used to optimize the invention. The following specific preferred embodiments are therefore merely exemplary and are not intended to limit the remainder of the disclosure in any way.

In the above and below examples all temperatures are given in degrees Celsius and all parts are parts by weight unless otherwise stated.

The entire disclosure of all applications, patents and publications, cited above and below, is hereby incorporated by reference.

[0058]

【Example】

 [Examples 1 to 27] (all 1.8 mm thick)

[0059]

[Table 1]

A: Example 2 of US Pat. No. 5,190,896
2. Measured at 1.8 mm thickness. b: Example 22 of U.S. Pat. No. 5,190,896 under reducing conditions (Example B; 0.5 wt% carbon added: Example C; 0.1 wt% carbon added) c: Neutral and oxidative batch conditions US patents below
Example 22 of 5,190,896 [all carbonates used as batch component (Example 1); nitrates used as batch component (Example 2)]. d: Example 22 of US Pat. No. 5,190,896 with the addition of cobalt

[0061]

[Table 2]

E: Iron is out of range.

[0063]

[Table 3]

F: Cerium is out of range.

[0065]

[Table 4]

G: Titanium is out of range.

[0067]

[Table 5]

[0068]

[Table 6]

Example 28 The amount of Fe ^{+2 in} the glass was determined by the determination of the ferrous / ferric ratio in the nuclear waste containing glass.
It can be measured by a colorimetric method using a ferrozine colorimetric method developed in Dupont. Al
_The sample is ground in a ₂ O ₃ vial and dissolved in HF-H ₂ SO ₄ containing NH ₄ VO ₃ to preserve Fe (II). After adding boric acid to complex the fluoride, a colored Fe (II) -ferrozine complex is formed at pH 5,
The absorbance (A1) was measured with a Hitachi U-3210 spectrophotometer.
It was measured at 2 nm. Then, Fe (III) in the sample was converted to Fe (II) by adding ascorbic acid, and total Fe (I
I) Absorbance (A2) was measured. The percentage of Fe (II) was calculated from these measured absorbance values as follows. A1 / (A2-A1) * 100 =% Fe (II) The following values are the average of three measurements. <Example><% Fe (II)> Example 22 7.0 of US Pat. No. 5,190,896 Example 3 3.0 Example 1 3.0 Example B 51.6 Example C 6.6

The above examples are also provided by substituting the reactants and / or operating conditions of the invention described generally or specifically for the reactants and / or operating conditions used in the examples. , Can be reproduced as well.

From the above description, one skilled in the art can ascertain the essential features of this invention and, to adapt it to various applications and conditions, without departing from the spirit and scope of this invention. Various changes and modifications can be made.

 ─────────────────────────────────────────────────── —————————————————————————————————————————————————————————————————————————————————— 18709 Pennsylvania Lutheran, Walnut Street 468

Claims (25)

[Claims] 1. A glass composition comprising the following components, wherein oxide weight% SiO ₂ 40 to 72 B ₂ O ₃₀ to 13 Al ₂ O ₃ 0.5 to 3 Li ₂ O 0 to 3 Na ₂ O. 8 ~ 15 K ₂ O 1 ~ 10 TiO ₂ 4.2 ~ 10.2 CeO ₂ 0.5 ~ 3.5 Nd ₂ O ₃ 5.0 ~ 16.5 Fe ₂ O ₃ 2.5 ~ 4.0 CoO 0.00 ~ 0.02 NiO 0.06 ~ 0.33 ZnO 0.0 ~ 7.0 Er ₂ O ₃ 0 〜 2 Cr ₂ O ₃ 0.0 〜 0.2 V ₂ O ₅ 0.0 〜 0.2 CuO 0.00 〜 0.10 MnO ₂ 0.0 〜 2.0 Has the following properties,% T _{V, C} (1.8 mm thickness) 14 〜 30 a −0.1 〜 +6 .0 b +18.0 to + 26.0% T (380 nm; 1.8 mm thickness) 0.0% T (400 nm; 1.8 mm thickness) ≤ 1.5 ANSI Z80.3-1986 D ₆₅₀₀ (1.8 mm thickness) and traffic signal A glass composition in which the amount of Fe ^{+2 in} the glass is chosen such that it meets the (1.8 mm thickness) specification and is sufficiently low to achieve the "a" and traffic signal characteristics. 2. The amount of Fe ^{+2 is} equal to the amount of iron ions in the glass.
The glass of claim 1, which is less than 5%. 3. The composition is such that oxide weight% SiO ₂ 45 to 65 B ₂ O ₃ 0.5 to 5 Al ₂ O ₃ 0.5 to 2.5 Li ₂ O 0.0 to 2.7 Na ₂ O 8.5 to 15.0 K ₂ O 1.0 to 8.5. _{TiO 2 5.2 ~ 9.2 CeO 2 1} ~ 3 Nd 2 O 3 5.0 ~ 14 Fe 2 O 3 2.6 ~ 3.7 CoO 0.00 ~ 0.017 NiO 0.10 ~ 0.25 ZnO 0.0 ~ 6.5 Er 2 O 3 0 ~ 1.0 Cr 2 O 3 0.00 ~ 0.17 The glass of claim 1, which is V ₂ O ₅ 0.00 to 0.17 CuO 0.00 to 0.08 MnO ₂ 0.0 to 1.8. 4. The glass of claim 3 having the following properties:% T _{V, C} (1.8 mm thickness) 14-25 a −0.1 to +5.5 b +18.5 to +25.5. 5. The composition is such that oxide weight% SiO ₂ 48 to 60 B ₂ O ₃ 0.5 to 2.5 Al ₂ O ₃ 0.5 to 1.5 Li ₂ O 0.0 to 2.4 Na ₂ O 9 to 15 K ₂ O 1.0 to 7.5. TiO ₂ 6 ~ 9 CeO ₂ 1.5 ~ 2.8 Nd ₂ O ₃ 5.0 ~ 13.0 Fe ₂ O ₃ 2.7 ~ 3.6 CoO 0.000 ~ 0.015 NiO 0.11 ~ 0.24 ZnO 0.0 ~ 6.0 Er ₂ O ₃ 0.0 ~ 0.5 Cr ₂ O ₃ 0.00 ~ 0.15 a _{V 2 O 5 0.0 ~ 0.15 CuO} 0.00 ~ 0.07 MnO 2 0.0 ~ 1.4, a glass of claim 1. 6. The glass of claim 5 having the following properties:% T _{V, C} (1.8 mm thickness) 15-24 a −0.1 to +4.5 b +19.0 to +25.0. 7. The glass of claim 1, which has been melted under oxidizing conditions. 8. The glass of claim 1 having at least one chemically strengthened surface. 9. A brown sunglasses lens made of the glass of claim 1 and having a low ultraviolet ray transmittance. 10. Sunglasses including a sunglasses frame and the sunglasses lens of claim 9. 11. A glass composition comprising the following components, wherein oxide weight% SiO ₂ 40 to 72 B ₂ O ₃₀ to 13 Al ₂ O ₃ 0.5 to 3 Li ₂ O 0 to 3 Na ₂ O. 8 ~ 15 K ₂ O 1 ~ 10 TiO ₂ 4.2 ~ 10.2 CeO ₂ 0.5 ~ 3.5 Nd ₂ O ₃ 5.0 ~ 16.5 Fe ₂ O ₃ 2.5 ~ 4.0 CoO 0.0053 ~ 0.02 NiO 0.06 ~ 0.33 ZnO 0.0 ~ 7.0 Er ₂ O ₃ 0 〜 2 Cr ₂ O ₃ 0.0 〜 0.2 V ₂ O ₅ 0.0 〜 0.2 CuO 0.00 〜 0.10 MnO ₂ 0.0 〜 2.0 Has the following properties,% T _{V, C} (1.8 mm thickness) 14 〜 30 a −0.1 〜 +6 .0 b +18.0 to + 26.0% T (380 nm; 1.8 mm thickness) 0.0% T (400 nm; 1.8 mm thickness) ≤ 1.5 ANSI Z80.3-1986 D ₆₅₀₀ (1.8 mm thickness) and traffic signal (1.8 mm thickness) A glass composition that complies with the standard. 12. The glass of claim 11, wherein the amount of Fe ^{+2 in} the glass is selected such that the "a" and traffic signal characteristics are low enough to be achieved. 13. The composition is oxide weight% SiO ₂ 45 to 65 B ₂ O ₃ 0.5 to 5 Al ₂ O ₃ 0.5 to 2.5 Li ₂ O 0.0 to 2.7 Na ₂ O 8.5 to 15.0 K ₂ O 1.0 to 8.5. _{TiO 2 5.2 ~ 9.2 CeO 2 1} ~ 3 Nd 2 O 3 5.0 ~ 14 Fe 2 O 3 2.6 ~ 3.7 CoO 0.0053 ~ 0.017 NiO 0.10 ~ 0.25 ZnO 0.0 ~ 6.5 Er 2 O 3 0.0 ~ 1.0 Cr 2 O 3 0.00 ~ 0.17 The glass composition according to claim 11, which is V ₂ O ₅ 0.0 to 0.17 CuO 0.00 to 0.08 MnO ₂ 0.0 to 1.8. 14. The glass of claim 13 having the following properties:% T _{V, C} (1.8 mm thickness) 14-25 a −0.1 to +5.5 b +18.5 to +25.5. 15. The following composition, oxide weight% SiO ₂ 48 to 60 B ₂ O ₃ 0.5 to 2.5 Al ₂ O ₃ 0.5 to 1.5 Li ₂ O 0.0 to 2.4 Na ₂ O 9 to 15 K ₂ O 1.0 to 7.5. TiO ₂ 6 ~ 9 CeO ₂ 1.5 ~ 2.8 Nd ₂ O ₃ 5.0 ~ 13.0 Fe ₂ O ₃ 2.7 ~ 3.6 CoO 0.0053 ~ 0.015 NiO 0.11 ~ 0.24 ZnO 0.0 ~ 6.0 Er ₂ O ₃ 0.0 ~ 0.5 Cr ₂ O ₃ 0.00 ~ 0.15 The glass according to claim 11, which is V ₂ O ₅ 0.00 to 0.15 CuO 0.00 to 0.07 MnO ₂ 0.0 to 1.4. 16. The glass of claim 15 having the following properties:% T _{V, C} (1.8 mm thickness) 15-24 a −0.1 to +4.5 b +19.0 to +25.0. 17. The glass of claim 11 having at least one chemically strengthened surface. 18. A sunglasses lens having a low ultraviolet absorption rate, which is made of the glass of claim 11. 19. Sunglasses including a sunglasses frame and the sunglasses lens of claim 18. 20. The glass of claim 1, wherein the amount of Fe ₂ O ₃ is at least 2.8% by weight. 21. The glass of claim 11, wherein the amount of Fe ₂ O ₃ is at least 2.8% by weight. 22. The glass of claim 1, wherein the amount of Fe ⁺² is less than 3% of the amount of iron in the glass. 23. The glass of claim 1 having an antireflective coating. 24. The glass according to claim 11, which has an antireflection coating. 25. The glass of claim 1 containing La ₂ O ₃ in a range up to 11.5% by weight.