阅读说明：本技术 着色玻璃及其制造方法 (Colored glass and method for producing same ) 是由 池西干男 丹野义刚 金子将士 广川奈绪美 于 2019-01-31 设计创作，主要内容包括：本发明的课题在于,提供一种折射率大的着色玻璃及其制造方法。本发明提供一种玻璃,其折射率nd为1.75以上,该玻璃包含以厚度1.0mm计可见光的透射率的最大值为50％以下的部分。(The present invention addresses the problem of providing a colored glass having a high refractive index and a method for producing the same. The present invention provides a glass having a refractive index nd of 1.75 or more, the glass including a portion in which the maximum value of visible light transmittance is 50% or less in a thickness of 1.0 mm.)

1. A glass having a refractive index nd of 1.75 or more,

the glass contains a portion in which the maximum value of the visible light transmittance is 50% or less when converted to a thickness of 1.0 mm.

2. A glass having a refractive index nd of 1.75 or more,

the glass contains Ti³⁺The content of (b) is 0.1 mass ppm or more.

3. A glass having a refractive index nd of 1.75 or more,

the glass comprises an electrical conductivity of 10^-8A fraction of S/m or more.

4. A glass according to any one of claims 1 to 3 which is a phosphate glass.

5. The glass according to any one of claims 1 to 4, wherein the glass contains Nb ions as a glass component in an amount of 1 cation% or more.

6. The glass according to any one of claims 1 to 5, wherein the glass contains Ti ions as a glass component in an amount of 0.5 cation% or more.

7. The glass according to any one of claims 1 to 6, which contains Li as a glass component⁺And Na⁺The total content thereof is 0.1 cation% or more.

8. The glass according to any one of claims 1 to 7, having an average linear expansion coefficient of 50 × 10^-7K^-1The above.

9. The glass according to any one of claims 1 to 8, wherein,

the acid resistance of the glass based on jog is grade 1.

10. The glass according to any one of claims 1 to 9, comprising a crystallized portion.

11. The glass of any one of claims 1-10, comprising a chemically strengthened moiety.

12. A composite glass, comprising:

either or both of a metal material and a ceramic, and

the glass as claimed in any one of claims 1 to 11.

13. A method for producing a glass having a refractive index nd of 1.75 or more and containing a portion in which the maximum value of visible light transmittance is 50% or less when converted into a thickness of 1.0mm,

the method comprises the following steps:

and a step of heat-treating the molded glass in a reducing atmosphere.

14. A method for producing a glass having a refractive index nd of 1.75 or more and containing a portion in which the maximum value of visible light transmittance is 50% or less when converted into a thickness of 1.0mm,

the method comprises the following steps:

and obtaining molten glass in a reducing atmosphere.

15. A method for producing a glass having a refractive index nd of 1.75 or more and containing a portion in which the maximum value of visible light transmittance is 50% or less when converted into a thickness of 1.0mm,

the method comprises the following steps:

adding water vapor to the molten atmosphere.

Technical Field

The present invention relates to a colored glass and a method for producing the same.

Background

Since ancient times, materials having strong luster like gemstones have been widely used as ornaments. A material having a strong gloss looks shiny because the surface reflects a large amount of light. That is, the reflectance of the surface of the material having strong gloss is large. Here, the larger the reflectance of the surface, the larger the refractive index. Therefore, a material having a large refractive index can have a strong luster like a gem.

Among the gemstones, diamond is a representative example, and many gemstones having strong luster and high transparency exist. On the other hand, a colored but less transparent gemstone is less shiny. However, even if the material has low transparency, if it has strong gloss, the decorative effect is high, and it is useful. Further, if the material is more excellent in workability than a gem and is available at a low price, the usefulness is further improved.

Glass is a material having a large refractive index, superior in workability to gemstones, available at low cost, and capable of being colored. Methods for reducing transmittance by coloring glass are described in the patent literatureThis is disclosed in document 1. Patent document 1 discloses the following: for P₂O₅-WO₃Glass-like, P₂O₅-Nb₂O₅Glass-like, P₂O₅-TiO₂Glass-like, which is colored by exposing it to a non-oxidizing atmosphere at elevated temperatures. However, in patent document 1, the transmittance of the glass is low, about 60%, even at a thickness of 2 mm. Therefore, further colored glass, that is, glass having a lower transmittance is required. Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2002-201041

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a colored glass having a high refractive index and a method for producing the same.

Means for solving the problems

The gist of the present invention is as follows.

(1) A glass having a refractive index nd of 1.75 or more,

the glass contains a portion having a maximum value of visible light transmittance of 50% or less in terms of a thickness of 1.0 mm.

(2) A glass having a refractive index nd of 1.75 or more,

the above glass contains Ti³⁺The content of (b) is 0.1 mass ppm or more.

(3) A glass having a refractive index nd of 1.75 or more,

the glass contains an electrical conductivity of 10^-8The fraction of S/cm or more.

(4) The glass according to any one of (1) to (3), which is a phosphate glass.

(5) The glass according to any one of (1) to (4), which contains Nb ions as a glass component in an amount of 1 cation% or more.

(6) The glass according to any one of (1) to (5), which contains Ti ions as a glass component in an amount of 0.5 cation% or more.

(7) The glass according to any one of (1) to (6), which contains Li as a glass component⁺And Na⁺The total content thereof is 0.1 cation% or more.

(8) The glass according to any one of (1) to (7), which has an average linear expansion coefficient of 50 × 10^-7K^-1The above.

(9) The glass according to any one of (1) to (8),

the acid resistance of the above glass based on jog is grade 1.

(10) The glass according to any one of (1) to (9), which contains a crystallized portion.

(11) The glass according to any one of (1) to (10), which comprises a chemically strengthened portion.

(12) A composite glass, comprising:

either or both of a metal material and a ceramic, and

(1) the glass according to any one of (1) to (11).

(13) A method for producing a glass having a refractive index nd of 1.75 or more and containing a portion in which the maximum value of visible light transmittance is 50% or less in terms of thickness 1.0mm,

the method comprises the following steps:

and a step of heat-treating the molded glass in a reducing atmosphere.

(14) A method for producing a glass having a refractive index nd of 1.75 or more and containing a portion in which the maximum value of visible light transmittance is 50% or less in terms of thickness 1.0mm,

the method comprises the following steps:

and obtaining molten glass in a reducing atmosphere.

(15) A method for producing a glass having a refractive index nd of 1.75 or more and containing a portion in which the maximum value of visible light transmittance is 50% or less in terms of thickness 1.0mm,

the method comprises the following steps:

adding water vapor to the molten atmosphere.

Drawings

FIG. 1 shows an example of transmittance of a glass of an embodiment of the present invention at a wavelength of 400 to 760 nm.

FIG. 2 shows an example of transmittance of the glass of the embodiment of the present invention at a wavelength of 400 to 760 nm.

FIG. 3 shows an example of transmittance of the glass of the embodiment of the present invention at a wavelength of 400 to 760 nm.

FIG. 4 shows an example of transmittance of the glass of the embodiment of the present invention at a wavelength of 400 to 760 nm.

FIG. 5 shows an example of transmittance of the glass of the embodiment of the present invention at a wavelength of 400 to 2500 nm. The graphs show, in order from the top, the cases where the atmosphere control was not performed in the melting step (comparative example 4-1), where 0.1 wt% of the alcohol was added (example 4-1), where 0.3 wt% of the alcohol was added (example 4-2), where 0.5 wt% of the alcohol was added (example 4-3), and where 5 wt% of the alcohol was added (example 4-4).

Fig. 6 schematically shows an example of a device for applying a voltage to glass in the embodiment of the present invention.

Fig. 7 shows an example of a case where the glass according to the embodiment of the present invention is partially discolored.

Fig. 8 shows an example of the transmittance of a discolored part and a non-discolored part in the glass according to the embodiment of the present invention. The solid line graph shows, in order from the top, after decoloring (decolored portion) and before decoloring (non-decolored portion).

Fig. 9 is a photograph showing an example of a cross section of a boundary between a discolored portion and a non-discolored portion in a glass according to an embodiment of the present invention.

Fig. 10 is a transmittance curve in the visible region of the glass of the embodiment of the present invention.

Fig. 11 is a transmittance curve in the visible region of the glass of the embodiment of the present invention.

Fig. 12 is a transmittance curve in the visible region of the glass of the embodiment of the present invention.

Fig. 13 is a transmittance curve in the visible region of the glass of the embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail. In this embodiment, the glass of the present invention will be described based on the content ratio of each component expressed by cation%. Therefore, "%" in each content represents "% cation", unless otherwise specified.

The cation% represents a molar percentage in which the total content of all the cation components is 100%. The total content is the total amount of the plurality of cationic components (including the case where the content is 0%). The cation ratio is a ratio of the contents of the cation components (including the total content of the plurality of cation components) in the cation% expression.

The content of the glass component can be determined by a known method, for example, inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), or the like. In the present specification and the present invention, the content of the constituent component of 0% means that the constituent component is not substantially contained, and the content of the constituent component is allowed to be at an inevitable impurity level.

In the present specification, unless otherwise specified, the refractive index "nd" refers to a refractive index "nd" of helium d-ray (wavelength 587.56 nm).

The present invention will be described below in the form of embodiment 1, embodiment 2, embodiment 3, and embodiment 4. The characteristics of the glasses in embodiments 2, 3, and 4 are common to those of the glass in embodiment 1. The action and effect of each glass component in embodiment 2, embodiment 3, and embodiment 4 are also similar to those of each glass component in embodiment 1. Therefore, in embodiment 2, embodiment 3, and embodiment 4, the description of embodiment 1 is omitted as appropriate for overlapping matters.

Embodiment 1

The glass of embodiment 1 has a refractive index nd of 1.75 or more,

the glass contains a portion having a maximum value of visible light transmittance of 50% or less in terms of a thickness of 1.0 mm.

(refractive index)

In the glass of embodiment 1, the refractive index nd is 1.75 or more, preferably 1.76 or more, and more preferably 1.77 or more, 1.78 or more, 1.79 or more, and 1.80 or more in the following order. The upper limit of the refractive index nd is not particularly limited, but is usually 2.50, preferably 2.30. In the present embodiment, the refractive index nd may be measured directly or after reducing the coloring of the glass. Examples of the method for reducing coloring include a method of applying a voltage and a heat treatment described later. As a method for reducing the coloring of the glass by the heat treatment, a method of heating the glass in the vicinity of Tg in an atmospheric atmosphere for several hours to several tens of hours can be cited.

(transmittance)

The glass of embodiment 1 includes a colored portion, specifically, a portion in which the maximum value of the visible light transmittance is 50% or less when converted to a thickness of 1.0 mm. The glass of the present embodiment includes a portion in which the maximum value of the visible light transmittance is preferably 40% or less in terms of the thickness of 1.0mm, and may include a portion in which the maximum value of the visible light transmittance is 30% or less, 20% or less, 15% or less, 10% or less, 5% or less, 2% or less, or 1% or less. The maximum value of the transmittance of visible light may be 0%. The region in which the maximum value of the visible light transmittance is within the above range when converted into a thickness of 1.0mm may be a part of the glass or the entire glass. The visible light is light having a wavelength of 400 to 760 nm.

The glass of embodiment 1 may include a portion whose transmittance at a wavelength of 1100nm is preferably 80% or less in terms of a thickness of 1.0mm, and may include a portion whose transmittance at a wavelength of 1100nm is 70% or less, 60% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, 0.5% or less, 0.3% or less, 0.1% or less, 0.05% or less, or 0.03% or less. The region having the above-mentioned transmittance at a wavelength of 1100nm in terms of a thickness of 1.0mm may be a part of the glass or the entire glass.

In the glass of embodiment 1, the maximum value of visible light transmittance is 50% or less in the colored portion, that is, in the portion having a thickness of 1.0mm, and the glass component composition is the same in the other portions. The glass composition is also the same in the colored portion and the portion decolorized by applying a voltage by the method described later. However, the valence of the glass component (cation) may be different between the colored portion and the other portions. In the same manner, the valence number of the glass component (cation) may be different between the colored portion and the decolored portion. The same applies to a portion having a transmittance at a wavelength of 1100nm of 80% or less when converted into a thickness of 1.0mm, and other portions.

The glass of embodiment 1 will be described in detail below.

(Ti³⁺Content of (1)

The glass of embodiment 1 preferably comprises Ti³⁺The content of (B) is 0.1 mass ppm or more, and Ti may be contained³⁺The content of (b) is 0.3 mass ppm or more, 0.5 mass ppm or more, 1 mass ppm or more, 5 mass ppm or more, 15 mass ppm or more, 25 mass ppm or more, 50 mass ppm or more, 70 mass ppm or more, or 90 mass ppm or more. Ti³⁺The upper limit of (b) is not particularly limited, but is usually 10000 ppm by mass, preferably 5000 ppm by mass. Ti³⁺The region having the content of (b) within the above range may be a part of the glass or the whole. Ti³⁺The content of (b) can be measured by ESR (electron spin resonance).

In the glass of embodiment 1, the coloring is preferably a reduction color due to a glass component, and more preferably a reduction color due to a transition metal. Examples of the transition metal include Ti, Nb, Bi, and W.

The glass develops color according to the valence of these transition metals. For example, among Ti contained as a glass component, 4-valent Ti⁴⁺Is reduced to Ti of 3 valence³⁺When this occurs, the glass is colored. Similarly, when Nb, Bi, and W are reduced and the valence changes, the glass is colored.

Therefore, in the glass of the present embodiment, Ti has a valence of 4⁴⁺Is reduced to a valence of 3 Ti³⁺The portion (c) may be colored, that is, the maximum value of the visible light transmittance may be 50% or less when converted to a thickness of 1.0 mm. And, by mixing Ti³⁺When the content of (b) is in the above range, the degree of coloring of the portion can be improved.

(conductivity)

The glass of embodiment 1 comprises a portion having electrical conductivity, preferably having an electrical conductivity of 10^-8The fraction having S/cm or more may contain a fraction having an electric conductivity of 10^-7S/cm over 10^-6S/cm over 10^-55 × 10 of S/cm or more^-5S/cm over 10^-45 × 10 of S/cm or more^-4S/cm over 10^-35 × 10 of S/cm or more^-3S/cm or more, or 10^-2The fraction of S/cm or more. The upper limit of the conductivity is not particularly limited, and is usually 10²S/cm, preferably 1S/cm. The region having the above range of conductivity may be a part of the glass or the entire glass. The electrical conductivity can be measured, for example, by the ac impedance method. The measurement temperature of the electrical conductivity is set to a temperature which is 200 ℃ lower than the glass transition temperature Tg (Tg-200 ℃) or higher and lower than the glass transition temperature Tg.

In the glass of embodiment 1, the portion having conductivity is colored, that is, the maximum value of the visible light transmittance when converted to a thickness of 1.0mm may be 50% or less. When the coloration of the glass is reduced, the conductivity decreases, and when the coloration is increased, the conductivity increases. Therefore, when either one of the coloration and the conductivity of the glass is adjusted, the other is also adjusted. For example, the coloring of the glass may be adjusted so that the electrical conductivity is in the above range.

In addition, in the glass of embodiment 1, coloring can be reduced by applying a voltage to the glass under a certain condition and oxidizing the glass component by ion conduction. That is, by applying a voltage to a colored portion of glass under certain conditions, the visible light transmittance of the portion can be increased.

Specifically, by applying a voltage to the glass of embodiment 1 in a state of being heated to a glass softening temperature Ts or lower, the transmittance of the colored portion can be increased.

In particular, in the colored portion of the glass of embodiment 1, the electrode is brought into contact with the glass polished to a thickness of 1.0mm in the thickness direction in an atmospheric atmosphere at a temperature of 200 ℃ or higher (Tg-200 ℃) lower than the glass transition temperature Tg and at a temperature of not higher than the softening point, and a voltage is applied under conditions of a voltage of 20kv or lower and a treatment time of 5 hours or less, whereby the change amount of the maximum value of the transmittance at a wavelength of 400 to 760nm before and after the application of the voltage can be made to be 10% or higher.

In the above-described treatment, the pattern may be decolored by applying a voltage locally.

In the glass of the present embodiment, the glass transition temperature Tg is preferably in the range of 350 to 850 ℃, and more preferably in the order of 370 to 830 ℃, 380 to 800 ℃, 400 to 770 ℃, 420 to 740 ℃, 440 to 710 ℃, and 440 to 680 ℃.

(average linear expansion coefficient)

In the glass of embodiment 1, the average linear expansion coefficient is preferably 50 × 10^-7K^-1The above sequence is more preferably 60 × 10^-7K^-170 × 10 of the above^-7K^-175 × 10 of the above^-7K^-180 × 10 of the above^-7K^-185 × 10 from above^-7K^-190 × 10 of the above^-7K^-1The upper limit of the average linear expansion coefficient is not particularly limited, but is usually 200 × 10^-7K^-1Preferably 150 × 10^-7K^-1. By setting the average linear expansion coefficient to the above range, the strength of the glass can be improved when chemical strengthening described later is performed.

The average linear expansion coefficient was measured according to the Japanese society for optical glass (Nitro) Standard JOGIS08-2003 "method for measuring thermal expansion of optical glass". The diameter of the round bar-shaped sample was set to 5 mm.

(acid-resistant weight reduction ratio Da)

In the glass of embodiment 1, the acid-resistant weight reduction rate Da is preferably rated on the order of 1 to 2, and more preferably rated on the order of 1.

The acid-resistant weight reduction rate Da is measured according to the regulation of the Japan optical glass Industrial Association Standard JOGIS 06-2009. Specifically, a powder glass (particle size: 425 to 600 μm) having a weight equivalent to the specific gravity was placed in a platinum cage, and the platinum cage was immersed in a quartz glass round-bottomed flask containing 0.01mol/L of an aqueous nitric acid solution, and the treatment was carried out in a boiling water bath for 60 minutes, and the weight reduction (%) before and after the treatment was measured. The grades based on the acid resistance weight reduction rate Da are shown in table a.

[ Table A ]

Stage	Weight loss (%)
		1	Less than 0.20
2	0.20 or more and less than 0.35
		3	0.35 or more and less than 0.65
4	0.65 or more and less than 1.20
		5	1.20 or more and less than 2.20
6	2.20 or more

(βOH)

In the glass of embodiment 1, the lower limit of the value of β OH represented by formula (1) below is preferably 0.3mm^-1Further, it is more preferably 0.4mm in the following order^-1、0.5mm^-1、0.6mm^-1、0.7mm^-1、O.8mm^-1、0.9mm^-1、1.0mm^-1、1.05mm^-1、1.1mm^-1、1.15mm^-1In addition, the upper limit of the value of β OH is preferably 4.5mm^-1Further, it is more preferably 4.0mm in the following order^-1、3.8mm^-1、3.5mm^-1、3.0mm^-1、2.5mm^-1、2.3mm^-1、2.2mm^-1、2.1mm^-1、2.0mm^-1。

βOH＝-[ln(B/A)]/t···(1)

In the formula (1), t represents the thickness (mm) of the glass used for measuring the external transmittance, a represents the external transmittance (%) at a wavelength of 2500nm when the glass is incident in parallel with the thickness direction thereof, B represents the external transmittance (%) at a wavelength of 2900nm when the glass is incident in parallel with the thickness direction thereof, ln is a natural logarithm, and β OH has a unit of mm^-1。

The "external transmittance" refers to a ratio (Iout/Iin) of an intensity Iout of transmitted light transmitted through the glass to an intensity Iin of incident light entering the glass, that is, a transmittance in consideration of surface reflection on the glass surface. The transmittance was obtained by measuring the transmission spectrum using a spectrophotometer. As the spectroscopic device, "UV-3100 (Shimadzu)" can be used. The external transmittance may be measured directly or after reducing the coloring of the glass. Examples of the method for reducing coloring include a method of applying a voltage and a heat treatment described later. As a method for reducing the coloring of the glass by the heat treatment, a method of heating the glass in the vicinity of Tg in an atmospheric atmosphere for several hours to several tens of hours can be cited.

The β OH represented by the above formula (1) is specified based on the fact that: the transmittance changes according to the absorption of light due to hydroxyl groups. Therefore, by evaluating β OH, the concentration of water (and/or hydroxide ions) contained in the glass can be evaluated. That is, a glass having a high β OH means that the concentration of water (and/or hydroxide ions) contained in the glass is high.

When a voltage is applied to the glass or the glass is heat-treated in order to reduce the coloring of the glass, the application time or the heat treatment time can be shortened by setting the value of β OH to the above range. On the other hand, when the value of β OH is too large, the transition metal ion component contained in the glass is easily precipitated as a metal. In addition, when glass is melted, the amount of volatile matter from the molten glass may increase.

(color tone)

The color tone of the glass of embodiment 1 can be changed by adjusting the external transmittance in the visible light region (wavelength of 400 to 760 nm). Specifically, the color tone of the glass can be changed by adjusting the transmittance curve (the horizontal axis represents the wavelength in the visible light region (wavelength of 400 to 760nm), and the vertical axis represents the external transmittance) of the glass to a shape having a predetermined characteristic.

For example, in order to obtain a glass having a blue color or a black glass having a blue color, the transmittance curve in the visible light region (wavelength of 400 to 760nm) may have the following characteristics. That is, 1) has a maximum value in a wavelength range of 400 to 450nm and a transmittance at a wavelength of 400nm is greater than a transmittance at a wavelength of 760 nm; or 2) has no maximum value and no minimum value and has a maximum value of transmittance in the wavelength range of 400 to 450 nm.

In order to obtain glass having a red color or black glass having a red color, the transmittance curve in the visible light region (wavelength of 400 to 760nm) may have no maximum value or minimum value and may have a maximum value of transmittance in the wavelength range of 700 to 760 nm.

In order to obtain a glass having a magenta color or a black glass having a magenta color, the transmittance curve in the visible light region (wavelength of 400 to 760nm) may be made to have a minimum value in the wavelength range of 450 to 550nm, and the transmittance at the wavelength of 400nm may be made smaller than the transmittance at the wavelength of 760 nm.

Here, the maximum value refers to a point where the external transmittance is shifted from increase to decrease in the transmittance curve, and the minimum value refers to a point where the external transmittance is shifted from decrease to increase in the transmittance curve. The maximum value of the transmittance is the maximum value of the external transmittance in the visible light region (wavelength of 400 to 760 nm).

(glass composition)

Non-limiting examples of the glass composition of the glass of embodiment 1 are shown below.

The glass of embodiment 1 is preferably phosphate glass. The phosphate glass means that it mainly contains P⁵⁺Glass as a network forming component of glass. As a network-forming component of glass, P is known⁵⁺、B³⁺、Si⁴⁺、Al³⁺And the like. Here, the fact that phosphate is mainly contained as a network-forming component of the glass means that P is P⁵⁺In an amount greater than B³⁺、Si⁴⁺、Al³⁺Content of any one of them. By using phosphate glass, the degree of coloration of the glass can be increased.

In the glass of embodiment 1, P⁵⁺The lower limit of the content of (b) is preferably 10%, and more preferably 13%, 15%, 17%, 20% in the following order. In addition, P⁵⁺The upper limit of the content of (b) is preferably 50%, and more preferably 45%, 43%, 40%, 38%, 35% in the following order.

P⁵⁺Is a network forming component of the glass, and has the function of keeping the thermal stability of the glass. On the other hand, an excess of P⁵⁺In the case of this, the meltability is deteriorated. Thus, P⁵⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, B³⁺The upper limit of the content of (b) is preferably 35%, and more preferably 30%, 25%, 20%, 15%, 13%, 10% in the following order. In addition, B³⁺The lower limit of the content of (B) is preferably 0%, further based onMore preferably, the content is 0.1%, 0.3%, 0.5%, 1%, 3%, 5% in the following order. B is³⁺The content of (B) may be 0%.

B³⁺Is a network-forming component of glass and has an effect of improving the meltability of glass. On the other hand, B³⁺When the content of (b) is too large, chemical durability tends to be lowered. Thus, B³⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, B³⁺Relative to P⁵⁺Content of cation ratio [ B ]³⁺/P⁵⁺]The upper limit of (b) is preferably 0.95, and more preferably 0.93, 0.9, 0.8, 0.7, 0.6, 0.55, 0.5 in this order. Cation ratio [ B³⁺/P⁵⁺]And may be 0.

In the glass of embodiment 1, Si⁴⁺The upper limit of the content of (b) is preferably 10%, and more preferably 7%, 5%, 3%, 2%, 1% in the following order. Si⁴⁺The content of (B) may be 0%.

Si⁴⁺Is a network forming component of glass, and has the functions of improving the thermal stability, chemical durability and weather resistance of the glass. On the other hand, Si⁴⁺When the content of (b) is too large, the meltability of the glass is lowered, and the non-melted portion of the glass raw material tends to remain. Thus, Si⁴⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, Al³⁺The upper limit of the content of (b) is preferably 10%, and more preferably 7%, 5%, 3%, 1% in the following order. Al (Al)³⁺The content of (B) may be 0%.

Al³⁺Has the function of improving the chemical durability and the weather resistance of the glass. On the other hand, Al³⁺When the content of (b) is too large, the refractive index decreases, the thermal stability of the glass decreases, the glass transition temperature Tg increases, and the meltability tends to decrease. Thus, Al³⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, P⁵⁺、B³⁺、Si⁴⁺And Al³⁺Total content of [ P ]⁵⁺+B³⁺+Si⁴⁺+Al³⁺]The lower limit of (b) is preferably 10%, and more preferably 15%, 18%, 20%, 23%, 25% in the following order. In addition, the total content [ P ]⁵⁺+B³⁺+Si⁴⁺+Al³⁺]The upper limit of (b) is preferably 60%, and more preferably 55%, 53%, 50%, 45%, 40%, 37% in the following order.

In the glass of embodiment 1, the glass component preferably contains a transition metal, and more preferably has Ti selected from Ti represented by a cation⁴⁺、Nb⁵⁺、Bi³⁺And W⁶⁺At least 1 glass component of (1), and further preferably contains Ti⁴⁺。

In the glass of embodiment 1, the lower limit of the content of Ti ions is preferably 0.1%, and more preferably 0.5%, 1%, 1.5%, 2%, 3% in the following order. The upper limit of the content of Ti ions is preferably 45%, and more preferably 40%, 38%, 35%, 33%, and 30% in the following order. Here, the Ti ion contains Ti⁴⁺、Ti³⁺All Ti ions having different equivalent numbers.

Like Nb ions, W ions, and Bi ions, Ti ions contribute significantly to an increase in refractive index, and also have an effect of increasing the coloring of glass. On the other hand, when the content of Ti ions is too large, the meltability of the glass is lowered, and the non-melted portion of the glass raw material tends to remain. Therefore, the content of Ti ions is preferably in the above range.

In the glass of embodiment 1, the lower limit of the content of Nb ions is preferably 0.1%, and more preferably 0.5%, 1%, 5%, 10%, 13%, 15%, 17% in the following order. The upper limit of the content of Nb ions is preferably 50%, and more preferably 45%, 43%, 40%, and 38% in the following order. The Nb ion contains Nb⁵⁺All Nb ions with different equivalent numbers.

The Nb ion contributes to an increase in refractive index, and is a component for increasing the coloring of the glass. In addition, the glass has the effect of improving the thermal stability and chemical durability of the glass. On the other hand, when the content of Nb ions is too large, the thermal stability of the glass tends to be lowered. Therefore, the content of Nb ions is preferably in the above range.

In the glass of embodiment 1, the upper limit of the content of W ions is preferably 30%, and more preferably 25%, 20%, 15%, and 13% in the following order. The content of W ion may be 0%. W ion contains W⁶⁺All W ions with different equivalence numbers.

The W ion contributes to an increase in refractive index and also has an effect of increasing coloring of the glass. On the other hand, when the content of the W ion is too large, the thermal stability of the glass tends to be lowered. Therefore, the content of W ions is preferably in the above range.

In the glass of embodiment 1, the upper limit of the content of Bi ions is preferably 35%, and more preferably 30%, 28%, and 25% in the following order. The content of Bi ions may be 0%. The Bi ions contain Bi³⁺All Bi ions having different equivalent numbers.

The Bi ions contribute to an increase in refractive index and also have an effect of increasing the coloring of the glass. In addition, Bi ions have an effect of increasing the swelling of the glass. On the other hand, when the content of Bi ions is too large, the thermal stability of the glass tends to be lowered. Therefore, the content of Bi ions is preferably in the above range.

In the glass of embodiment 1, the lower limit of the total content [ Ti + Nb + W ] of Ti ions, Nb ions, and W ions is preferably 0.1%, and more preferably 0.5%, 1%, 3%, 5%, 10%, 15%, 20%, 22% in the following order. The upper limit of the total content [ Ti + Nb + W ] is preferably 75%, and more preferably 70%, 65%, 63%, 60%, 58% in the following order.

In the glass of embodiment 1, the lower limit of the total content [ Ti + Nb + W + Bi ] of Ti ions, Nb ions, W ions, and Bi ions is preferably 0.1%, and more preferably 0.5%, 1%, 3%, 5%, 10%, 15%, 20%, 22%, 25% in the following order. The upper limit of the total content [ Ti + Nb + W + Bi ] is preferably 80%, and more preferably 75%, 73%, 70%, and 67% in the following order.

In the glass of embodiment 1, Ta⁵⁺In an amount ofThe upper limit of (b) is preferably 5%, and more preferably 3%, 2%, 1% in the following order. Ta⁵⁺The content of (B) may be 0%.

Ta⁵⁺Has the function of improving the thermal stability of the glass. On the other hand, Ta⁵⁺When the content of (b) is too large, the glass tends to have a low refractive index and to have a low melting property. Thus, Ta⁵⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, the total content of Ti ions, Nb ions, W ions, and Bi ions is P⁵⁺、B³⁺And Si⁴⁺The cation ratio of the total content of [ (Ti + Nb + W + Bi)/(P ]⁵⁺+B³⁺+Si⁴⁺)]The lower limit of (b) is preferably 0.1, and more preferably 0.3, 0.4, 0.5, 0.55, 0.6, 0.7 in this order. In addition, the cation ratio [ (Ti + Nb + W + Bi)/(P)⁵⁺+B³⁺+Si⁴⁺)]The upper limit of (b) is preferably 8, and more preferably 5, 4, 3, 2.7, 2.5 in the following order.

In the glass of embodiment 1, Li is preferably contained as a glass component⁺And Na⁺Either or both, more preferably contains Li⁺And Na⁺The total content is more than 0.1%. By making the glass contain Li⁺Or Na⁺Chemical enhancement described later can be performed.

In the glass of embodiment 1, Li⁺The upper limit of the content of (b) is preferably 35%, and more preferably 30%, 27%, 25%, 22%, 20% in the following order. In addition, Li⁺The lower limit of the content of (b) is preferably 0.1%, and more preferably 0.5%, 1%, 3%, 5%, 10%, 15% in the following order. Li⁺The content of (B) may be 0%.

In the glass of embodiment 1, Na⁺The upper limit of the content of (b) is preferably 45%, and more preferably 40%, 38%, 35%, 33% in the following order. In addition, Na⁺The lower limit of the content of (b) is preferably 0.1%, and more preferably 0.5%, 1%, 3%, 5%, 10%, 13%, 15%, 17% in the following order. Na (Na)⁺The content of (B) may be 0%.

By making the glass contain Li⁺Or Na⁺The glass may be subjected to chemical strengthening as described later. On the other hand, Li⁺Or Na⁺If the content of (b) is too large, the thermal stability of the glass may be lowered. Thus, Li⁺And Na⁺The respective contents of (a) and (b) are preferably within the above ranges.

In the glass of embodiment 1, K⁺The upper limit of the content of (b) is preferably 30%, and more preferably 25%, 23%, 20%, 17%, 15% in the following order. In addition, K⁺The lower limit of the content of (b) is preferably 0.1%, and more preferably 0.3%, 0.5%, 1% in the following order. K⁺The content of (B) may be 0%.

K⁺Has the function of improving the thermal stability of the glass. On the other hand, K⁺When the content of (b) is too large, thermal stability tends to be lowered. Thus, K⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, Li⁺And Na⁺Total content of [ Li ]⁺+Na⁺]The upper limit of (b) is preferably 50%, and more preferably 45%, 43%, 40%, and 38% in the following order. Further, the total content [ Li⁺+Na⁺]The lower limit of (b) is preferably 0.1%, 0.5%, and more preferably 1%, 5%, 10%, 13%, 15% in the following order.

In the glass of embodiment 1, Rb⁺The upper limit of the content of (b) is preferably 5%, and more preferably 3%, 1%, and 0.5% in the following order. Rb⁺The content of (B) may be 0%.

In the glass of embodiment 1, Cs⁺The upper limit of the content of (b) is preferably 5%, and more preferably 3%, 1%, and 0.5% in the following order. Cs⁺The content of (B) may be 0%.

Rb⁺And Cs⁺Has the effect of improving the meltability of glass. On the other hand, when the content thereof is too large, the refractive index nd may decrease and the volatilization of the glass component during melting may increase. Thus, Rb⁺And Cs⁺The respective contents of (a) and (b) are preferably within the above ranges.

In the glass of embodiment 1, Mg²⁺The upper limit of the content of (b) is preferably 15%, and more preferably 10%, 5%, 3%, 1% in the following order. Mg (magnesium)²⁺The content of (B) may be 0%.

In the glass of embodiment 1, Ca²⁺The upper limit of the content of (b) is preferably 15%, and more preferably 10%, 5%, 3%, 1% in the following order. Ca²⁺The content of (B) may be 0%.

In the glass of embodiment 1, Sr²⁺The upper limit of the content of (b) is preferably 15%, and more preferably 10%, 5%, 3%, 1% in the following order. Sr²⁺The content of (B) may be 0%.

In the glass of embodiment 1, Ba²⁺The upper limit of the content of (b) is preferably 20%, and more preferably 15%, 10%, and 5% in the following order. Ba²⁺The content of (B) may be 0%.

Mg²⁺、Ca²⁺、Sr²⁺And Ba²⁺All have the function of improving the thermal stability and the melting property of the glass. In addition, Ba²⁺Has the effect of improving the expansion of the glass. On the other hand, when the content is too large, the high refractivity is impaired, and the thermal stability of the glass may be lowered. Therefore, the content of each of these glass components is preferably within the above range.

In the glass of embodiment 1, Mg²⁺、Ca²⁺、Sr²⁺And Ba²⁺Total content of [ Mg ]²⁺+Ca²⁺+Sr²⁺+Ba²⁺]The upper limit of (b) is preferably 30%, and more preferably 25%, 20%, 18%, 15%, 10%, 5%, 3%, 1% in the following order. Total content [ Mg²⁺+Ca²⁺+Sr²⁺+Ba²⁺]The concentration may be 0%.

In the glass of embodiment 1, Zn²⁺The upper limit of the content of (b) is preferably 15%, and more preferably 10%, 8%, 5%, 3%, 1.5% in the following order. Zn²⁺The content of (B) can also be 0%。

Zn²⁺Has the function of improving the thermal stability of the glass. On the other hand, Zn²⁺If the content of (b) is too large, the meltability may be deteriorated. Thus, Zn²⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, Zr⁴⁺The upper limit of the content of (b) is preferably 5%, and more preferably 3%, 2%, and 1% in the following order. Zr⁴⁺The content of (B) may be 0%.

Zr⁴⁺Has the function of improving the thermal stability of the glass. On the other hand, Zr⁴⁺When the content of (b) is too large, the thermal stability and meltability of the glass tend to be lowered. Thus, Zr⁴⁺The content of (b) is preferably in the above range.

In the glass of embodiment 1, Ga³⁺The upper limit of the content of (b) is preferably 3%, and more preferably 2% and 1% in the following order. In addition, Ga³⁺The lower limit of the content of (b) is preferably 0%. Ga³⁺The content of (B) may be 0%.

In the glass of embodiment 1, In³⁺The upper limit of the content of (b) is preferably 3%, and more preferably 2% and 1% in the following order. In addition, In³⁺The lower limit of the content of (b) is preferably 0%. In³⁺The content of (B) may be 0%.

In the glass of embodiment 1, Sc³⁺The upper limit of the content of (b) is preferably 3%, and more preferably 2% and 1% in the following order. In addition, Sc³⁺The lower limit of the content of (b) is preferably 0%. Sc (Sc)³⁺The content of (B) may be 0%.

In the glass of embodiment 1, Hf⁴⁺The upper limit of the content of (b) is preferably 3%, and more preferably 2% and 1% in the following order. In addition, Hf⁴⁺The lower limit of the content of (b) is preferably 0%. Hf (hafnium)⁴⁺The content of (B) may be 0%.

In the glass of embodiment 1, Lu³⁺The upper limit of the content of (b) is preferably 3%, and more preferably 2% and 1% in the following order. In addition, Lu³⁺The lower limit of the content of (b) is preferably 0%. Lu (Lu)³⁺The content of (B) may be 0%.

In the glass of embodiment 1, Ge⁴⁺The upper limit of the content of (b) is preferably 3%, and more preferably 2% and 1% in the following order. In addition, Ge⁴⁺The lower limit of the content of (b) is preferably 0%. Ge (germanium) oxide⁴⁺The content of (B) may be 0%.

In the glass of embodiment 1, La³⁺The upper limit of the content of (b) is preferably 5%, and more preferably 4%, 3%, 2%, 1% in the following order. In addition, La³⁺The lower limit of the content of (b) is preferably 0%. La³⁺The content of (B) may be 0%.

In the glass of embodiment 1, Gd³⁺The upper limit of the content of (b) is preferably 5%, and more preferably 4%, 3%, 2%, 1% in the following order. In addition, Gd³⁺The lower limit of the content of (b) is preferably 0%. Gd (Gd)³⁺The content of (B) may be 0%.

In the glass of embodiment 1, Y³⁺The upper limit of the content of (b) is preferably 5%, and more preferably 4%, 3%, 2%, 1% in the following order. In addition, Y³⁺The lower limit of the content of (b) is preferably 0%. Y is³⁺The content of (B) may be 0%.

In the glass of embodiment 1, Yb³⁺The upper limit of the content of (b) is preferably 5%, and more preferably 4%, 3%, 2%, 1% in the following order. In addition, Yb³⁺The lower limit of the content of (b) is preferably 0%. Yb of³⁺The content of (B) may be 0%.

The cation component of the glass of embodiment 1 preferably mainly contains the above-mentioned component, i.e., P⁵⁺、B³⁺、Si⁴⁺、Al³⁺Ti ion, Nb ion, W ion, Bi ion, Ta⁵⁺、Li⁺、Na⁺、K⁺、Rb⁺、Cs⁺、Mg²⁺、Ca²⁺、Sr²⁺、Ba²⁺、Zn²⁺、Zr⁴⁺、Ga^{3 +}、In³⁺、Sc³⁺、Hf⁴⁺、Lu³⁺、Ge⁴⁺、La³⁺、Gd³⁺、Y³⁺And Yb³⁺The total content of the above components is preferably more than 95%, more preferably more than 98%, still more preferably more than 99%, still more preferably more than 99.5%,

the glass of embodiment 1 may contain other than F^-And O^2-The other components are anionic components. As a means for removing F^-And O^2-Other anionic components, Cl may be exemplified^-、Br^-、I^-. However, Cl^-、Br^-、I^-Are easily volatilized in the melting of glass. Volatilization of these components causes problems such as change in glass characteristics, reduction in glass homogeneity, and significant consumption of melting equipment. Thus, Cl^-The content of (b) is preferably less than 5 anions%, more preferably less than 3 anions%, still more preferably less than 1 anion%, particularly preferably less than 0.5 anions%, still more preferably less than 0.25 anions%. In addition, Br^-And I^-The total content of (b) is preferably less than 5 anions%, more preferably less than 3 anions%, still more preferably less than 1 anion%, particularly preferably less than 0.5 anions%, still more preferably less than 0.1 anions%, and still more preferably 0 anions%.

The anion% refers to a molar percentage in which the total content of all anion components is 100%.

The glass of embodiment 1 is preferably composed substantially of the above components, but may contain other components within a range not to impair the action and effect of the present invention.

For example, the glass of embodiment 1 may contain an appropriate amount of copper (Cu) as a glass component in order to impart near-infrared light absorption characteristics to the glass. Further, V, Cr, Mn, Fe, Co, Ni, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Ce, etc. may be contained. They can increase the coloration of the glass and become a source of fluorescence.

In the present invention, the inclusion of inevitable impurities is not excluded.

< composition of other ingredients >

Pb, As, Cd, Tl, Be, Se are toxic. Therefore, the glass of embodiment 1 preferably does not contain these elements as glass components.

U, Th and Ra are radioactive elements. Therefore, the glass of embodiment 1 preferably does not contain these elements as glass components.

Sb₂O₃、SnO₂And CeO₂Is a glass component which functions as a fining agent and can be added arbitrarily. Wherein Sb³⁺Is a clarifying agent with large clarifying effect.

Sb₂O₃The contents of (A) are expressed in terms of the ratio of addition. That is, in the expression based on oxide, Sb is removed₂O₃、SnO₂And CeO₂Sb is Sb when the total content of all other glass components is 100 mass%₂O₃The content of (b) is preferably less than 2% by mass, more preferably less than 1% by mass, still more preferably less than 0.5% by mass, yet more preferably less than 0.3% by mass, and particularly preferably less than 0.2% by mass. Sb₂O₃The content of (b) may be 0 mass%. By mixing Sb₂O₃When the content of (b) is in the above range, the glass can be improved in the fining property.

SnO₂And CeO₂The contents of (A) are also shown in an added ratio. That is, in the expression based on oxide, Sb is removed₂O₃、SnO₂And CeO₂SnO when the total content of all other glass components is 100% by mass₂And CeO₂The content of (b) is preferably less than 2% by mass, more preferably less than 1% by mass, still more preferably less than 0.5% by mass, and still more preferably less than 0.1% by mass. SnO₂And CeO₂Each content of (b) may be 0 mass%. By adding SnO₂And CeO₂When the contents of (a) and (b) are within the above ranges, the glass can be improved in the clarity.

(production of glass)

The glass of embodiment 1 may be produced by blending glass raw materials and by a known glass production method. For example, a plurality of compounds are blended and mixed well to form a batch material, and the batch material is put into a melting vessel, melted, clarified, homogenized, molded into molten glass, and slowly cooled to obtain glass. Alternatively, the raw materials may be put into a melting vessel and subjected to a coarse melting (rough melt). The melt obtained by the rough melting is quenched and pulverized to produce cullet. Further, the cullet is put into a melting vessel, heated and remelted (remelt) to produce molten glass, and after further clarification and homogenization, the molten glass is molded and slowly cooled to obtain glass. The molten glass may be molded or slowly cooled by any known method.

The process for producing glass according to embodiment 1 may include a step of heat-treating the glass after molding in a reducing atmosphere. The degree of coloring of the glass can be increased by heat-treating the glass in a reducing atmosphere. Examples of the reducing gas used as the reducing atmosphere include hydrogen gas. Hereinafter, the heat treatment process of the glass in the reducing atmosphere will be described in detail.

First, the formed glass was placed in a vacuum/gas replacement furnace, and the pressure was reduced. Next, a reducing gas is introduced into the furnace until the atmospheric pressure is reached. However, the temperature in the furnace is raised to a temperature (Tg-400 ℃) of 400 ℃ or higher and a softening point or lower than the glass transition temperature Tg, and the glass is held at the temperature for about several minutes to several hours to be heat-treated.

In the heat treatment step in the reducing atmosphere, when hydrogen is used as the reducing gas, the atmosphere may be replaced with nitrogen before the atmosphere in the furnace is replaced with hydrogen. By replacing the atmosphere in the furnace with nitrogen gas, argon gas in the furnace is removed, and ignition and the like at the time of introducing hydrogen gas later are prevented in advance, whereby the furnace can be heated safely.

The glass production step of embodiment 1 may include a step of melting the glass in a reducing atmosphere to obtain molten glass. The reducing atmosphere is preferably a strongly reducing atmosphere. The process for producing glass of the present embodiment may include a step of adding a carbon-containing compound during melting. By including such a step, the degree of coloring of the glass can be improved.

The glass production process of embodiment 1 may include a step of increasing the amount of water in the molten glass. Examples of the step of increasing the amount of water in the molten glass include: adding water vapor in a molten atmosphere; and blowing a gas containing water vapor into the melt. Among them, the method preferably includes a step of adding water vapor in a molten atmosphere. The beta OH value of the glass can be increased by including a step of increasing the amount of water in the molten glass.

(crystallization)

The glass of embodiment 1 can be crystallized by heat treatment. That is, the glass of embodiment 1 may include a crystallized portion. The crystallized region may be a part of the glass or the entire glass. The crystallization also includes formation of crystal nuclei. In addition, it is preferable that the glass of embodiment 1 is not softened but maintains its shape before heating when subjected to heat treatment for crystallization. As a method for crystallizing glass by heat treatment, a known method can be used.

In the glass of embodiment 1, the crystallinity of the crystallized portion may be 50% or more, and may be 60% or more, 70% or more, 80% or more, or 90% or more.

The crystallinity can be calculated as follows: the X-ray diffraction intensity was separated into a scattering intensity due to the crystal (crystal scattering intensity) and a scattering intensity due to the amorphous (amorphous scattering intensity) from an X-ray diffraction pattern obtained by X-ray diffraction measurement, and calculated as a ratio of the crystal scattering intensity to the total scattering intensity (crystal scattering intensity and amorphous scattering intensity) as shown in the following formula (2).

Degree of crystallinity (%) < 100 × (crystalline scattering intensity)/(crystalline scattering intensity + amorphous scattering intensity) · (2)

(chemical enhancement)

The glass of embodiment 1 can be chemically strengthened by bringing the glass into contact with a molten salt. Glass-to-glassWhen the glass is chemically strengthened, the glass preferably contains Li⁺And Na⁺Either or both of them as a glass component.

The method of chemical strengthening is not particularly limited, and a low-temperature type ion exchange method in which ion exchange is performed in a temperature region not exceeding the glass transition temperature is preferred. Chemical enhancement refers to the following treatments: when the molten chemical strengthening salt is brought into contact with the glass, the alkali metal element having a relatively large atomic radius in the chemical strengthening salt and the alkali metal element having a relatively small atomic radius in the glass are ion-exchanged, whereby the alkali metal element having a large atomic radius penetrates the surface layer of the glass, and compressive stress is generated on the surface of the glass.

For example, a glass containing sodium (Na) as a glass component is immersed in heated potassium nitrate (KNO)₃) In the molten salt of (3), sodium ions (Na) contained in the glass are generated⁺) With potassium ion (K)⁺) Ion exchange of (2).

Potassium ion (K)⁺) Is greater than sodium ion (Na)⁺) The size of (2). Therefore, a compressive stress layer that applies compressive stress is formed near the surface of the glass by ion exchange. In contrast, sodium ions (Na) contained in the glass⁺) Since there is almost no change from before chemical strengthening, the tensile stress layer is a tensile stress layer to which tensile stress is applied. As a result, a compressive stress layer is formed in the vicinity of the surface, and a tensile stress layer is formed therein, resulting in an increase in the strength of the glass.

For example, in the case of a glass containing lithium (Li) as a glass component, the glass may be impregnated with a solution containing sodium nitrate (NaNO)₃) With potassium nitrate (KNO)₃) The molten salt of (3). Alternatively, the glass may be immersed in sodium nitrate (NaNO)₃) After ion exchange in the molten salt of (2), the resultant was immersed in potassium nitrate (KNO)₃) Is ion exchanged in the molten salt of (3). The glass may also be impregnated with sodium nitrate (NaNO)₃) Molten salt of single salt, or potassium nitrate (KNO)₃) Single salt in molten salt. Larger than lithium ion (Li) may be used⁺) Sodium ion (Na) of⁺) And potassium ion (K)⁺) Any of (1) to lithium ions (Li) in the vicinity of the surface of the glass⁺) Ion exchange is performed.

Whether or not the glass is chemically strengthened can be investigated by, for example, energy dispersive X-ray analysis (EDX). Specifically, the contents of monovalent cations such as alkali metals and silver in the vicinity of the surface of the glass and in the glass were measured by EDX. The composition of the inside of the glass is measured by cutting the glass to expose a cross section of the glass. When the content of monovalent cations having a relatively large ionic radius in the vicinity of the surface of the glass is larger than that in the interior of the glass, the glass is considered to have undergone chemical strengthening. In addition, the measurement can be confirmed by a distorter for measuring the photoelastic characteristic of glass.

In the present embodiment, the heat treatment step in the reducing atmosphere described above may be performed before or after the chemical strengthening described above. Further, the transmittance of visible light may be improved by applying a voltage to the glass before or after the above-described chemical strengthening to oxidize the glass component.

(composite glass)

The glass of embodiment 1 may be combined with other materials to make a composite glass. Examples of the other materials include metallic materials and ceramics. That is, the composite glass of the present embodiment may include either one or both of a metal material and a ceramic, and include the glass of embodiment 1.

The metal material is not particularly limited, and examples thereof include a steel sheet for enamel, cast iron, stainless steel, aluminum, an aluminum-plated steel sheet, an aluminum-zinc alloy-plated steel sheet, aluminum, copper, electrolytic copper, a copper-zinc alloy, silver, and gold.

The ceramic is not particularly limited, and examples thereof include ceramics, refractories, glass, cement, fine ceramics, and the like.

The method for producing the composite glass is not particularly limited. For example, a method of coating a metal material or ceramic, or a method of firing a glass material is mentioned. More specifically, for example, a method known as a method for producing enamel or a method for producing cloisonne can be applied. The glass frit for manufacturing an enamel can be manufactured using the glass of embodiment 1. The glaze may contain a colorant, an additive, and the like as needed.

The glass portion contained in the composite glass may have the characteristics of the glass of embodiment 1 described above. That is, the glass portion in the composite glass may contain a colored portion, a crystallized portion, or a chemically strengthened portion.

Embodiment 2

The glass of embodiment 2 has a refractive index nd of 1.750 or more,

the glass contains Ti³⁺The content of (b) is 0.1 mass ppm or more.

(refractive index)

In the glass of embodiment 2, the refractive index nd is 1.75 or more, and more preferably 1.76 or more, 1.77 or more, 1.78 or more, 1.79 or more, and 1.80 or more in the following order. The upper limit of the refractive index nd is not particularly limited, but is usually 2.50, preferably 2.30. In the present embodiment, the refractive index nd may be measured directly or after reducing the coloring of the glass. Examples of the method for reducing coloring include a method of applying a voltage and a heat treatment described later. As a method for reducing the coloring of the glass by the heat treatment, a method of heating the glass in the vicinity of Tg in an atmospheric atmosphere for several hours to several tens of hours can be cited.

(Ti³⁺Content of (1)

The glass of embodiment 2 contains Ti³⁺The content of (b) is 0.1 mass ppm or more. The glass of the present embodiment contains Ti³⁺The content of (B) is preferably 0.3 mass ppm or more, and Ti may be contained³⁺The content of (b) is 0.5 mass ppm or more, 1 mass ppm or more, 5 mass ppm or more, 10 mass ppm or more, 20 mass ppm or more, 30 mass ppm or more, 40 mass ppm or more, 45 mass ppm or more, 50 mass ppm or more, 60 mass ppm or more, 70 mass ppm or more, 80 mass ppm or more, 85 mass ppm or more, or 90 mass ppm or more. Ti³⁺The upper limit of (b) is not particularly limited, but is usually 10000 ppm by mass, preferably 5000 ppm by mass. Ti³⁺In an amount ofThe region in the above range may be a part of the glass or the whole thereof. Ti³⁺The content of (b) can be measured by ESR (electron spin resonance).

In the glass of embodiment 2, the coloring is preferably a reduction color due to a glass component, and more preferably a reduction color due to a transition metal. Examples of the transition metal include Ti, Nb, Bi, and W.

The glass develops color depending on the valence number of these transition metals. For example, among Ti contained as a glass component, 4-valent Ti⁴⁺Is reduced to Ti of 3 valence³⁺When this occurs, the glass is colored. Similarly, when Nb, Bi, and W are reduced and the valence changes, the glass is colored.

Therefore, in the glass of the present embodiment, Ti has a valence of 4⁴⁺Is reduced to a valence of 3 Ti³⁺The portion (c) may be colored, that is, the maximum value of the visible light transmittance may be 50% or less when converted to a thickness of 1.0 mm. And, by mixing Ti³⁺When the content of (b) is in the above range, the degree of coloring of the portion can be improved.

The glass of embodiment 2 will be described in detail below.

(content of Ti ion)

In the glass of embodiment 2, the lower limit of the content of Ti ions is preferably 0.1%, and more preferably 0.5%, 1%, 1.5%, 2%, 3%, 5%, 10%, 15%, 20%, 25% in the following order. The upper limit of the content of Ti ions is preferably 45%, and more preferably 40%, 38%, 35%, 33%, and 30% in the following order. Here, the Ti ion contains Ti⁴⁺、Ti³⁺All Ti ions having different equivalent numbers.

(transmittance)

The glass of embodiment 2 includes a portion in which the maximum value of the visible light transmittance is preferably 50% or less when converted to a thickness of 1.0mm, and may include a portion in which the maximum value of the visible light transmittance is 40% or less, 30% or less, 20% or less, 15% or less, 10% or less, 5% or less, 2% or less, or 1% or less. The maximum value of the visible light transmittance may be 0%. The region in which the maximum value of the visible light transmittance is within the above range when converted into a thickness of 1.0mm may be a part of the glass or the entire glass. The visible light is light having a wavelength of 400 to 760 nm.

The glass of embodiment 2 may include a portion whose transmittance at a wavelength of 1100nm is preferably 80% or less in terms of a thickness of 1.0mm, and may include a portion whose transmittance at a wavelength of 1100nm is 70% or less, 60% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, 0.5% or less, 0.3% or less, 0.1% or less, 0.05% or less, or 0.03% or less. The region having the above-mentioned transmittance at a wavelength of 1100nm in terms of a thickness of 1.0mm may be a part of the glass or the entire glass.

In the glass of embodiment 2, the glass composition is the same in the colored portion, that is, the portion where the maximum value of the visible light transmittance is 50% or less when converted to the thickness of 1.0mm, and the other portions. The glass composition is also the same in the colored portion and the portion decolorized by applying a voltage by the method described later. However, the valence of the glass component (cation) may be different between the colored portion and the other portions. In the same manner, the valence number of the glass component (cation) may be different between the colored portion and the decolored portion. The same applies to a portion having a transmittance of 80% or less at a wavelength of 1100nm when converted into a thickness of 1.0mm, and other portions.

(conductivity)

The glass of embodiment 2 comprises a portion having electrical conductivity, preferably having an electrical conductivity of 10^-8The fraction of S/cm or more may contain a fraction having an electric conductivity of 10^-7S/cm over 10^-6S/cm over 10^-55 × 10 of S/cm or more^-5S/cm over 10^-45 × 10 of S/cm or more^-4S/cm over 10^-35 × 10 of S/cm or more^-3S/cm or more, or 10^-2The fraction of S/cm or more. The upper limit of the conductivity is notIs particularly limited, and is usually 10²S/cm, preferably 1S/cm. The region having the above range of conductivity may be a part of the glass or the entire glass. The electrical conductivity can be measured, for example, by the ac impedance method. The measurement temperature of the electrical conductivity is set to a temperature which is 200 ℃ lower than the glass transition temperature Tg (Tg-200 ℃) or higher and lower than the glass transition temperature Tg.

In the glass of embodiment 2, the portion having conductivity is colored, that is, the maximum value of the visible light transmittance when converted to a thickness of 1.0mm may be 50% or less. Further, the conductivity can be adjusted to the above range by adjusting the coloring of the glass.

In addition, in the glass of embodiment 2, coloring can be reduced by applying a voltage to the glass under a certain condition and oxidizing the glass component by ion conduction. That is, by applying a voltage to a colored portion of glass under certain conditions, the visible light transmittance of the portion can be increased.

Specifically, by applying a voltage to the glass of embodiment 2 in a state of being heated to a temperature equal to or lower than the glass softening temperature Ts, the transmittance of the colored portion can be increased.

In particular, in the colored portion of the glass of embodiment 2, the electrode is brought into contact with the glass polished to a thickness of 1.0mm in the thickness direction in an atmospheric atmosphere at a temperature of 400 ℃ or higher (Tg-400 ℃) lower than the glass transition temperature Tg and at a temperature of softening point or lower, and when a voltage is applied under conditions of a voltage of 20kv or lower and a treatment time of 5 hours or less, the change amount of the maximum value of the transmittance at a wavelength of 400 to 760nm before and after the voltage application can be 10% or more.

In the above-mentioned treatment, a pattern may be decolorized by applying a voltage locally.

In the glass of the present embodiment, the glass transition temperature Tg is preferably in the range of 350 to 850 ℃, and more preferably in the order of 370 to 830 ℃, 380 to 800 ℃, 400 to 770 ℃, 420 to 740 ℃, 440 to 710 ℃, and 440 to 680 ℃.

In the glass of embodiment 2, the average linear expansion coefficient, the acid resistance weight reduction rate Da, β OH, the color tone, and the glass composition other than the Ti ion content may be the same as those of embodiment 1. The glass of embodiment 2 can be produced, crystallized, and chemically strengthened in the same manner as embodiment 1, and can be made into a composite glass.

Embodiment 3

The glass of embodiment 3 has a refractive index nd of 1.75 or more,

the glass comprises an electrical conductivity of 10^-8The fraction of S/cm or more.

(refractive index)

In the glass of embodiment 3, the refractive index nd is 1.75 or more. Preferably 1.76 or more, and more preferably 1.77 or more, 1.78 or more, 1.79 or more, and 1.80 or more in the following order. The upper limit of the refractive index nd is not particularly limited, but is usually 2.50, preferably 2.30. In the present embodiment, the refractive index nd may be measured directly or after reducing the coloring of the glass. Examples of the method for reducing coloring include a method of applying a voltage and a heat treatment described later. As a method for reducing the coloring of the glass by the heat treatment, a method of heating the glass in the vicinity of Tg in an atmospheric atmosphere for several hours to several tens of hours can be cited.

(conductivity)

The glass of embodiment 3 includes a portion having conductivity, specifically, 10^-8The fraction of S/cm or more. The glass of the present embodiment preferably has an electrical conductivity of 10^-7The fraction having S/cm or more may contain a fraction having an electric conductivity of 10^-6S/cm over 10^-55 × 10 of S/cm or more^-5S/cm over 10^-45 × 10 of S/cm or more^-4S/cm over 10^-35 × 10 of S/cm or more^-3S/cm or more, or 10^-2The fraction of S/cm or more. The upper limit of the conductivity is not particularly limited, and is usually 10²S/cm, preferably 1S/cm. The region having the above range of conductivity may be a part of the glass or the entire glass. The conductivity can be measured by the ac impedance method. The measurement temperature of the electrical conductivity was set to glassA temperature at which the glass transition temperature Tg is lower by 200 ℃ (Tg-200 ℃) or higher and lower than the glass transition temperature Tg.

In the glass of embodiment 3, the portion having conductivity is colored, that is, the maximum value of the visible light transmittance at a thickness of 1.0mm may be 50% or less. Further, the conductivity can be adjusted to the above range by adjusting the coloring of the glass.

In the glass of embodiment 3, the coloring can be reduced by applying a voltage to the glass under a certain condition and oxidizing the glass component by ion conduction. That is, by applying a voltage to a colored portion of glass under certain conditions, the visible light transmittance of the portion can be increased.

Specifically, by applying a voltage to the glass of embodiment 3 in a state of being heated to a temperature equal to or lower than the glass softening temperature Ts, the transmittance of the colored portion can be increased.

In particular, in the colored portion of the glass of embodiment 3, the electrode is brought into contact with the glass polished to a thickness of 1.0mm in the thickness direction in an atmospheric atmosphere at a temperature of 400 ℃ or higher (Tg-400 ℃) lower than the glass transition temperature Tg and at a temperature of softening point or lower, and when a voltage is applied under conditions of a voltage of 20kv or lower and a treatment time of 5 hours or less, the change amount of the maximum value of the transmittance at a wavelength of 400 to 760nm before and after the voltage application can be 10% or more.

In the above-mentioned treatment, a pattern may be decolorized by applying a voltage locally.

In the glass of the present embodiment, the glass transition temperature Tg is preferably in the range of 350 to 850 ℃, and more preferably in the order of 370 to 830 ℃, 380 to 800 ℃, 400 to 770 ℃, 420 to 740 ℃, 440 to 710 ℃, and 440 to 680 ℃.

The glass of embodiment 3 will be described in detail below.

(transmittance)

The glass of embodiment 3 includes a portion in which the maximum value of the visible light transmittance is preferably 50% or less when converted to a thickness of 1.0mm, and may include a portion in which the maximum value of the visible light transmittance is 40% or less, 30% or less, 20% or less, 15% or less, 10% or less, 5% or less, 2% or less, or 1% or less. The maximum value of the visible light transmittance may be 0%. The region in which the maximum value of the visible light transmittance is within the above range when converted into a thickness of 1.0mm may be a part of the glass or the entire glass. The visible light is light having a wavelength of 400 to 760 nm.

The glass of embodiment 3 may include a portion whose transmittance at a wavelength of 1100nm is preferably 80% or less in terms of a thickness of 1.0mm, and may include a portion whose transmittance at a wavelength of 1100nm is 70% or less, 60% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, 0.5% or less, 0.3% or less, 0.1% or less, 0.05% or less, or 0.03% or less. The region having the above-mentioned transmittance at a wavelength of 1100nm in terms of a thickness of 1.0mm may be a part of the glass or the entire glass.

In the glass of embodiment 3, the glass composition is the same in the colored portion, that is, the portion where the maximum value of the visible light transmittance is 50% or less when converted to the thickness of 1.0mm, and the other portions. The glass composition is also the same in the colored portion and the portion decolorized by applying a voltage by the above-described method. However, the valence of the glass component (cation) may be different between the colored portion and the other portions. In the same manner, the valence number of the glass component (cation) may be different between the colored portion and the decolored portion. The same applies to a portion having a transmittance of 80% or less at a wavelength of 1100nm when converted into a thickness of 1.0mm, and other portions.

(Ti³⁺Content of (1)

The glass of embodiment 3 preferably comprises Ti³⁺The content of (B) is 0.5 mass ppm or more, and Ti may be contained³⁺Its component (A) is more than 5 ppm, more than 15 ppm, more than 25 ppm and more than 50 ppm70 ppm by mass or more, or 90 ppm by mass or more. Ti³⁺The upper limit of (b) is not particularly limited, but is usually 10000 ppm by mass, preferably 5000 ppm by mass. Ti³⁺The region having the content of (b) within the above range may be a part of the glass or the whole. Ti³⁺The content of (b) can be measured by ESR (electron spin resonance).

In the glass of embodiment 3, the coloring is preferably a reduction color due to a glass component, and more preferably a reduction color due to a transition metal. Examples of the transition metal include Ti, Nb, Bi, and W.

The glass develops color depending on the valence number of these transition metals. For example, among Ti contained as a glass component, 4-valent Ti⁴⁺Is reduced to Ti of 3 valence³⁺When this occurs, the glass is colored. Similarly, when Nb, Bi, and W are reduced and the valence changes, the glass is colored.

Therefore, in the glass of the present embodiment, Ti has a valence of 4⁴⁺Is reduced to a valence of 3 Ti³⁺The portion (c) may be colored, that is, the maximum value of the visible light transmittance may be 50% or less when converted to a thickness of 1.0 mm. And, by mixing Ti³⁺When the content of (b) is in the above range, the degree of coloring of the portion can be improved.

(content of Ti ion)

In the glass of embodiment 3, the lower limit of the content of Ti ions is preferably 0.1%, and more preferably 0.5%, 1%, 1.5%, 2%, 3%, 5%, 10%, 15%, 20%, 25% in the following order. The upper limit of the content of Ti ions is preferably 45%, and more preferably 40%, 38%, 35%, 33%, and 30% in the following order. Here, the Ti ion contains Ti⁴⁺、Ti³⁺All Ti ions having different equivalent numbers.

In the glass of embodiment 3, the average linear expansion coefficient, the acid-resistant weight reduction rate Da, β OH, the color tone, and the glass composition other than the content of Ti ions may be the same as those of embodiment 1. The glass of embodiment 3 can be produced, crystallized, and chemically strengthened in the same manner as embodiment 1, and can be made into a composite glass.

Embodiment 4

The gist of the glass of embodiment 4 is as follows.

[ 1] an electrically decolorizable colored glass having a transmittance characteristic in which the maximum value of the transmittance in a wavelength range of 500 to 1000nm is 0.102% or less when converted into a thickness of 1.0 mm.

[ 2] the colored glass according to [ 1], wherein,

by applying a voltage at a temperature 20 ℃ or lower than the glass transition temperature Tg, the transmittance of the colored glass increases.

[ 3] the colored glass according to [ 1] or [ 2], wherein,

in a temperature range of 400 ℃ or more lower than the glass transition temperature Tg and 20 ℃ or less lower than the glass transition temperature Tg, an electrode is brought into contact with a glass electrode polished to a thickness of 1.0mm in the thickness direction in an atmospheric atmosphere, and when a voltage is applied under conditions of a voltage of 1 to 20kv and a treatment time of 5 hours, the minimum value of the transmittance of the colored glass at a wavelength of 500 to 1000nm is 65% or more.

[ 4] the colored glass according to any one of [ 1] to [ 3], wherein,

the glass composition contains:

P₂O₅、

Li₂o or Na₂Any one of the oxygen (O) s,

and comprises a compound selected from TiO₂、Nb₂O₅、WO₃And Bi₂O₃At least 1 oxide of (1).

[ 5 ] A glass molding comprising:

a portion having a transmittance maximum value of 0.232% or less at a wavelength of 500 to 1000nm, and

in the portion where the minimum value of the transmittance in the wavelength range of 500 to 1000nm is 69.59% or more,

the glass composition of these portions is the same.

[ 6] production of colored glassMethod for producing colored glass containing Li₂O or Na₂Any one of O as a glass component, the method comprising:

adding water and a carbon-containing compound during melting.

[ 7] A method for producing a colored glass including a portion decolorized in a pattern, comprising:

and a step of locally applying a voltage.

[ 8] A method for decoloring colored glass, comprising:

for the compound containing Li₂O or Na₂And applying a voltage to any one of the O as a colored glass of the glass component.

[ 9 ] the decoloring method according to [ 8], wherein,

the colored glass contains P as a glass component₂O₅And comprises a material selected from TiO₂、Nb₂O₅、WO₃And Bi₂O₃At least 1 oxide of (1).

The glass of embodiment 4 will be described in detail below.

The glass of embodiment 4 is a colored glass having a transmittance characteristic in which the maximum value of the transmittance in the wavelength range of 500 to 1000nm is 0.102% or less in terms of the thickness of 1.0 mm. The maximum value of the transmittance may be 0%. The glass of embodiment 4 can be electrically decolored by, for example, the following method.

That is, the glass of embodiment 4 can be discolored by applying a voltage to the glass and oxidizing the glass components by ion conduction. Specifically, by applying a voltage at a temperature 20 ℃ or lower than the glass transition temperature Tg, the transmittance can be increased and electric decoloring can be performed. As a method of applying a voltage to glass, for example, a method of bringing an electrode into contact with glass and flowing an electric current is given.

In particular, in the glass of embodiment 4, the minimum value of the transmittance at a wavelength of 500 to 1000nm can be made 65% or more when the electrode is brought into contact with the glass polished to a thickness of 1.0mm in the thickness direction in an atmospheric atmosphere at a temperature range of 400 ℃ or more lower than the glass transition temperature Tg and 20 ℃ or less lower than the glass transition temperature Tg and a voltage is applied under conditions of a voltage of 1 to 20kv and a treatment time of 5 hours.

The glass of embodiment 4 preferably contains P₂O₅As a glass component. In addition, as the glass component, Li may be contained₂O or Na₂Any one of O may also contain TiO₂、Nb₂O₅、WO₃And Bi₂O₃At least 1 oxide of (1). That is, as the glass component, P is contained₂O₅Containing Li₂O or Na₂One of O and TiO may be contained₂、Nb₂O₅、WO₃And Bi₂O₃At least 1 oxide of (1). Further, it more preferably contains Li₂O and Na₂O both. The glass of embodiment 4 may have the glass composition disclosed in WO 2017/006998A1, or may have the same composition as the glass of embodiments 1 to 3. In order to impart near-infrared light absorption characteristics to the glass material, an appropriate amount of copper may be added as a glass component.

The glass molded body made of the glass of embodiment 4 may be decolorized in a pattern, and may have a portion with a high degree of coloration and a portion with a low degree of coloration. That is, the glass molded body according to embodiment 4 has a portion in which the maximum value of the transmittance at a wavelength of 500 to 1000nm is 0.232% or less and a portion in which the minimum value of the transmittance at a wavelength of 500 to 1000nm is 69.59% or more, and the glass component compositions of these portions may be the same.

In order to decolor the glass into a pattern, for example, a voltage may be locally applied to the glass.

The glass of embodiment 4 may be produced by blending glass raw materials and by a known glass production method. The glass of embodiment 4 may be produced in the same manner as in embodiment 1. The glass production method of embodiment 4 may further include a step of adding a carbon-containing compound during melting. By including such a step, glass colored in a deep color can be obtained. The glass production according to embodiment 4 may include a step of adding water during melting. By including such a step, a glass having a high β OH value can be obtained.

In the glass of embodiment 4, the average linear expansion coefficient and the acid-resistant weight reduction rates Da and β OH may be the same as those of embodiment 1. The glass of embodiment 4 can be crystallized and chemically strengthened as in embodiment 1, and can be made into a composite glass.