Near-infrared absorbing glass and near-infrared cut-off filter

Abstract

A near-infrared absorbing glass containing four or more types of main cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions, containing P ions, Li ions, and Cu ions as essential cations, and containing at least O ions as anions, the main cations being selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions. The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, the content of O ions in the glass composition represented by anion% is 90.0 anion% or more, the total content of oxides of the main cations is 90.0% or more on a molar basis in the glass composition on an oxide basis, and the total content of oxides of the main cations is 90.0% or more on a molar basis. And a specific composition content relationship is satisfied.

Description

[0001] This application is a divisional application of an application with a filing date of May 31, 2021, an application number of 202180049196.1, and an invention name of “Near-infrared absorption glass and near-infrared cutoff filter”. Technical Field

[0002] The present invention relates to near infrared absorbing glass and a near infrared cutoff filter. Background Art

[0003] In small cameras such as smartphones in recent years, the image information is not only digitized, but also various electronic calculations are performed on the image information to reconstruct the image. For example, extracting a specific object and adjusting the color and contrast of the image have become the mainstream. At this time, if color information that does not exist is input to the imaging element due to the reflection of light in the optical element, the information must be removed, which is not preferred.

[0004] The near infrared cut filter has a function of filtering out unnecessary near infrared light (wavelength 700 to 1200 nm) within the sensitivity wavelength range of the imaging element. Generally, the near infrared cut filter is often provided right in front of the imaging element.

[0005] As near-infrared cut filters, those made of near-infrared absorbing glass as a base material and polished on a flat plate are widely used.

[0006] Near infrared absorbing glass generally contains Cu ions. An example of the spectral transmission characteristics of near infrared absorbing glass is shown in Figure 1 It should be noted that Figure 1 The light absorption characteristics near the wavelength of 700 to 1200 nm are determined by the Cu ions (Cu 2+ Among them, glass containing Cu ions and P ions can show Cu ions (Cu 2+ ) has near-infrared absorption properties and is therefore useful as glass for near-infrared cutoff filters (see, for example, Patent Document 1).

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2014-12630

[0010] exist Figure 1In the transmittance curve after the wavelength of 600nm, the wavelength at which the transmittance reaches 50% is called the "half-value", which has become one of the main standards for near-infrared cut-off filters. The half-value varies depending on the specifications of the filter, but is mostly set in the wavelength range of 600nm to 650nm. As a general method to achieve the desired half-value, there are methods such as adjusting the thickness of the glass substrate according to the Lambert-Beer law, or adjusting the Cu ion (Cu) content in the glass. 2+ ) concentration in any condition. Summary of the invention

[0011] Problems to be solved by the invention

[0012] The near infrared cut filter is required to have not only excellent ability to cut near infrared rays (ie, to have a desired half value and low near infrared transmittance) but also high transmittance in the visible region (violet to red region).

[0013] In addition, in recent years, the imaging device modules installed in smartphones and the like have been required to be both compact and high-performance, and the thickness of the near-infrared cut filter has been required to be thinner. Therefore, in recent years, the thickness of the near-infrared absorbing glass has been expected to be reduced from the existing 1 mm to about 0.45 mm, 0.3 mm or 0.2 mm, and further to 0.1 mm.

[0014] If only the near-infrared absorbing glass is thinned, the optical density (number of moles × thickness) of CuO required for near-infrared absorption is reduced, resulting in a decrease in the near-infrared absorption efficiency. In order to solve this problem, it is considered to increase the amount of CuO. However, if only the amount of CuO is increased, the absorption of CuO reaches the visible region (i.e., the red region) near the wavelength of 600nm, and the transmittance on the short wavelength side also tends to decrease. Therefore, it is difficult to simultaneously maintain the transmittance in the visible region (purple region to red region) and the absorption of near-infrared rays.

[0015] In addition, for near-infrared absorbing glass, in order to provide a near-infrared cut filter suitable for use in a high-temperature and high-humidity environment, it is desired to suppress the reduction of weather resistance in a high-temperature and high-humidity environment. However, according to the research of the present inventors, it is not easy to suppress the reduction of weather resistance while maintaining the transmittance in the visible region (purple region to red region) and the absorption of near-infrared rays.

[0016] In view of the above situation, one embodiment of the present invention aims to provide a near-infrared absorbing glass which has high transmittance in the visible region (purple region to red region) even after thinning, has excellent near-infrared blocking ability, and can suppress the reduction of weather resistance, and a near-infrared cutoff filter made of the near-infrared absorbing glass.

[0017] Solutions to the problem

[0018] One embodiment of the present invention relates to a near-infrared absorbing glass (hereinafter also referred to as “glass 1”), comprising four or more main cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions,

[0019] Contains P ions, Li ions and Cu ions as essential cations,

[0020] and contains at least O ions as anions,

[0021] The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less,

[0022] In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more.

[0023] In the oxide-based glass composition,

[0024] On a molar basis,

[0025] The total content of the oxides of the above main cations is 90.0% or more,

[0026] MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%,

[0027] Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less,

[0028] B 2 O 3 With SiO 2 Total content (B 2 O 3 +SiO 2 ) is less than 3.0%,

[0029] CuO content is α 1 %above,

[0030] α 1 is the value calculated by the following formula 1,

[0031] (Formula 1)

[0032] α 1 =70400×exp(-2.855×R)

[0033] In the above formula 1,

[0034] R is the above-mentioned ratio (O ion / P ion).

[0035] In addition, one embodiment of the present invention relates to a near-infrared absorbing glass (hereinafter also referred to as “glass 2”), comprising four or more main cations selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions,

[0036] Contains P ions, Li ions and Cu ions as essential cations,

[0037] and contains at least O ions as anions,

[0038] The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less,

[0039] In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more.

[0040] In the oxide-based glass composition,

[0041] On a molar basis,

[0042] The total content of the oxides of the above main cations is 90.0% or more,

[0043] MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%,

[0044] Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less,

[0045] B 2 O 3 With SiO 2 Total content (B 2 O3 +SiO 2 ) is less than 3.0%,

[0046] The above-mentioned near infrared absorbing glass satisfies the following formula 2:

[0047] (Formula 2)

[0048] C-3200×exp(-2.278×R)≥0

[0049] In the above formula 2,

[0050] C is the average CuO content per molar volume of glass (unit: mmol / cc),

[0051] R is the above-mentioned ratio (O ion / P ion).

[0052] In addition, one embodiment of the present invention relates to a near-infrared absorbing glass (hereinafter also referred to as “glass 3”), comprising four or more main cations selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions,

[0053] Contains P ions, Li ions and Cu ions as essential cations,

[0054] and contains at least O ions as anions,

[0055] The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less,

[0056] In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more.

[0057] In the oxide-based glass composition,

[0058] On a molar basis,

[0059] The total content of the oxides of the above main cations is 90.0% or more,

[0060] MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%,

[0061] Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2O+K 2 O+ZnO) / Li 2 O) is 2.4 or less,

[0062] A calculated by the following formula 3 1 More than 2500,

[0063] (Formula 3)

[0064] A 1 ={O(P)-O(others)}×Cu

[0065] In the above formula 3,

[0066] O(P) represents the amount of oxygen in the oxide that constitutes P ions in the oxide-based glass composition.

[0067] O(others) represents the amount of oxygen obtained by removing the above O(P) from the amount of oxygen in the oxide constituting the above main cation in the glass composition based on oxides.

[0068] Cu represents the CuO content on a molar basis in the glass composition on an oxide basis.

[0069] In addition, one embodiment of the present invention relates to a near-infrared absorbing glass (hereinafter also referred to as “glass 4”), comprising four or more main cations selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions,

[0070] Contains P ions, Li ions and Cu ions as essential cations,

[0071] and contains at least O ions as anions,

[0072] The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less,

[0073] In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more.

[0074] In the oxide-based glass composition,

[0075] On a molar basis,

[0076] The total content of the oxides of the above main cations is 90.0% or more,

[0077] MgO and Al 2 O 3 Total content (MgO+Al 2 O3 ) is less than 8.0%,

[0078] Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less,

[0079] A calculated by the following formula 4 2 More than 700,

[0080] (Formula 4)

[0081] A 2 ={O(P)-O(others)}×C

[0082] In the above formula 4,

[0083] C is the average CuO content per molar volume of glass (unit: mmol / cc),

[0084] O(P) represents the amount of oxygen in the oxide that constitutes P ions in the oxide-based glass composition.

[0085] O(others) represents the amount of oxygen obtained by removing the above-mentioned O(P) from the amount of oxygen in the oxide constituting the above-mentioned main cation in the glass composition based on oxides.

[0086] One embodiment of the present invention relates to a near-infrared absorbing glass (hereinafter also referred to as “glass 5”), comprising four or more main cations selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions,

[0087] Contains P ions, Li ions and Cu ions as essential cations,

[0088] and contains at least O ions as anions,

[0089] The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less,

[0090] In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more.

[0091] In the oxide-based glass composition,

[0092] On a molar basis,

[0093] The total content of the oxides of the above main cations is 90.0% or more,

[0094] MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%,

[0095] Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less,

[0096] CuO content is α 2 %above,

[0097] α 2 is the value calculated by the following formula 5,

[0098] (Formula 5)

[0099] α 2 =(76522)×exp(-2.855×R)

[0100] In the above formula 5,

[0101] R is the above-mentioned ratio (O ion / P ion).

[0102] In addition, one embodiment of the present invention relates to a near-infrared absorbing glass (hereinafter also referred to as “glass 6”), comprising four or more main cations selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions,

[0103] Contains P ions, Li ions and Cu ions as essential cations,

[0104] and contains at least O ions as anions,

[0105] The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less,

[0106] In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more.

[0107] In the oxide-based glass composition,

[0108] On a molar basis,

[0109] The total content of the oxides of the above main cations is 90.0% or more,

[0110] MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%,

[0111] Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less,

[0112] The above-mentioned near infrared absorbing glass satisfies the following formula 6,

[0113] (Formula 6)

[0114] C-(3478)×exp(-2.278×R)≥0

[0115] In the above formula 6,

[0116] C is the average CuO content per molar volume of glass (unit: mmol / cc),

[0117] R is the above-mentioned ratio (O ion / P ion).

[0118] Effects of the Invention

[0119] According to one embodiment of the present invention, it is possible to provide a near-infrared absorbing glass which has a high transmittance in the visible region (purple region to red region) even after thinning, has excellent near-infrared shielding capability, and can suppress the reduction of weather resistance. Furthermore, according to one embodiment of the present invention, it is possible to provide a near-infrared cut filter made of such near-infrared absorbing glass. BRIEF DESCRIPTION OF THE DRAWINGS

[0120] Figure 1 An example of the spectral transmission characteristics of the near-infrared absorbing glass is shown. DETAILED DESCRIPTION

[0121] [Near infrared absorbing glass]

[0122] Hereinafter, Glasses 1 to 6 are also collectively referred to as “glass” or “near infrared absorbing glass”. Unless otherwise specified, descriptions related to glass composition and physical properties are applicable to all glasses in Glasses 1 to 6.

[0123] In the present invention and this specification, near-infrared absorbing glass refers to glass having the property of absorbing at least the entire region or part of the wavelength of the near-infrared wavelength range (wavelength 700 to 1200 nm). In addition, the near-infrared absorbing glass of one embodiment of the present invention contains O ions as constituent ions, and therefore, it can be oxide glass. Oxide glass refers to glass whose main network-forming component of glass is oxide. In addition, the near-infrared absorbing glass of one embodiment of the present invention contains O ions (anions) and P ions (cations) as constituent ions, and therefore, it can be phosphate glass. It should be noted that O ions are anions of oxygen atoms, and are also commonly referred to as oxide ions.

[0124] Hereinafter, glasses 1 to 6 will be described in more detail.

[0125] <Glass composition>

[0126] (Analysis Method)

[0127] The various components constituting glass can be quantified by known methods such as inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS).

[0128] Anion components contained in glass can be identified and quantified by a known analytical method, for example, ion chromatography, non-dispersive infrared absorption (ND-IR) or the like.

[0129] In the present invention and this specification, "the content of a component is 0%, is not contained, or is not introduced" means that the component is not substantially contained, but inclusion of the component at an unavoidable impurity level is permitted.

[0130] (Description of glass composition based on oxides)

[0131] Based on the results obtained by the above analysis, the content (unit: mol %) of each component in the oxide-based glass composition can be calculated. The specific method is as follows.

[0132] The content of element i (mass % of element P) obtained by the above-mentioned analysis method i ) divided by the atomic weight M of element i i , from which we can find the number of moles of each element n i =P i / M i .

[0133] In the above-mentioned element i is a cationic component A iIn the case of i Replace with the corresponding number of moles of oxide n' i Specifically, the cationic component A corresponding to element i i The composition formula of the oxide is A i When xOy is expressed, n' i =n i / x.

[0134] In the above-mentioned element i, the anion component B other than O ion i In the case of i Later recorded as m i .

[0135] Cationic component A in the glass composition based on oxides i Oxide A i xOy content PA i (mol%) by PA i =n' i / (Σn' i +Σm i )×100.

[0136] The content in the glass composition based on oxides may also be referred to as an oxide-based fraction.

[0137] In the oxide-based glass composition, the anion components B other than O ions i Oxide base fraction PB i (mol%) from PB i =m i / (Σn' i +Σm i )×100.

[0138] Here, Σn' i It is the oxide of the cationic component contained in the glass. i The total number of moles of xOy. The effective figures of the content are used so that even if trace amounts of components are ignored, the calculation results will not be affected.

[0139] (Anion %)

[0140] “Anion %” refers to the value calculated by “(content of anion i of interest expressed in mol %) / (total number of anions contained in glass expressed in mol %)×100”, and refers to the molar percentage of the anion amount of interest relative to the total amount of anions.

[0141] The anion percentage of O ions in the above description of the oxide-based glass composition can be expressed as (ΣOi -Σ(N k / 2)B k ) / (ΣO i -Σ(N k / 2)B k +ΣB k )×100, where A i xOy represents the cationic component A corresponding to element i i The composition formula of the oxide is as follows, and the cationic component A is used i Oxide base fraction PA i (mol%) The cationic component A i The number of O contained in the oxide is expressed as O i =PA i ×y, the anion component B k The valence number is expressed as N k .

[0142] Here, ΣO i is the sum of the molar numbers of O ions in the glass composition based on oxides, Σ(N k / 2)B k Indicates that the anion component B k The number of moles of O ions replaced. i -Σ(N k / 2)B k ) is the molar number of O ions contained in the glass.

[0143] On the other hand, in the present invention and this specification, regarding the oxygen content, when no anion components other than oxygen are detected by analysis based on a known method, all of the anion components (ie, 100 anion %) are O ions.

[0144] (Cationic component)

[0145] Regarding the valence of the cationic component, the formal valence of each cation is used. The formal valence refers to the valence necessary for the oxide of the cation of interest to maintain electrical neutrality when the valence of the O ions constituting the oxide is set to -2, and can be clearly determined from the chemical formula of the oxide.

[0146] For example, regarding Cu ions, in order to maintain the O contained in the chemical formula of the oxide CuO 2- The charge neutrality with Cu is +2. In addition, for example, P ions, in order to maintain the oxide P 2 O 5 The chemical formula contains O 2-The valence of P is +2×5 / 2=+5 due to its electrical neutrality with P. If this is summarized, the formal valence of the cation Ai contained in the oxide AixOy is "+2y / x". Therefore, when analyzing the glass composition, the valence of the cation does not need to be analyzed.

[0147] In addition, regarding the valence of anions (for example, the valence of O ions is -2), it is also a formal valence based on the idea that O ions accept two electrons and take a closed shell structure. Therefore, when analyzing the glass composition, it is not necessary to analyze the valence of anions. 2+ Part of it may become Cu during melting + , but usually its amount is very small, so the valence of Cu can all be regarded as +2.

[0148] (Anionic component)

[0149] The above-mentioned glass contains at least O ions as anions, and its content is 90.0 anion% or more in the glass composition expressed as anion%. The inventors believe that by reducing the O / P ratio in the glass mainly composed of O ions as anions, the absorption of CuO in the red region can be shifted to the long wavelength side, thereby increasing the content of CuO and improving the near-infrared blocking ability without reducing the transmittance in the red region. The O ion content in the glass composition expressed as anion% is 90.0% or more, preferably 95.0% or more, more preferably 98.0% or more, and further preferably 99.0% or more. From the perspective of suppressing volatilization during glass melting, it is also preferred that the proportion of O ions in the anion components is high. From the perspective of suppressing the generation of ribs, it is preferred to suppress volatilization during glass melting. In particular, from the perspective of suppressing volatilization during glass melting, improving productivity, and suppressing the generation of harmful gases during manufacturing, the content of O ions is preferably 100%. It should be noted that the formal valence of O ions is -2.

[0150] The glass may contain only O ions as anions in one embodiment, and may contain O ions and one or more other anions in another embodiment. Other anions include F ions, Cl ions, Br ions, I ions, etc. It should be noted that the formal valence of F ions, Cl ions, Br ions, and I ions is -1.

[0151] From the viewpoint of improving the homogeneity and strength of the glass, in the glass composition expressed as anion %, the content of F ions is preferably 15.0 anion % or less, more preferably 10.0 anion % or less, further preferably 5.0 anion % or less, further preferably 2.0 anion % or less, and further preferably 1.0 anion % or less. In particular, from the viewpoint of suppressing volatilization during glass melting, improving productivity, and suppressing the generation of harmful gases during manufacturing, the above-mentioned glass may be a glass that does not contain F ions.

[0152] (O / P ratio)

[0153] The molar ratio of the content of cations to the content of anions is the ratio of the contents (expressed in mole %) of the components of interest when the total amount of all cationic components and all anionic components is set to 100 mole %. Therefore, the ratio of the content of O ions to the content of P ions (O ions / P ions) is the ratio of the content of O ions (expressed in mole %) to the content of P ions (expressed in mole %) when the total amount of all cationic components and all anionic components is set to 100 mole %.

[0154] O / P ratio calculation method1

[0155] The O / P ratio (also described as R) can be calculated as follows based on the description of the above-described oxide-based glass composition:

[0156] A i xOy represents the cationic component A corresponding to element i i The composition formula of the oxide of the cationic component Ai is obtained by using the oxide reference fraction PAi (mol %) of the cationic component Ai and setting the number of O contained in the oxide of the cationic component Ai to O i =PA i ×y, the anion component B k The valence number is set to N k hour,

[0157] Formula D1: R1 = ΣO i -Σ(N k / 2)B k

[0158] Formula D2: R2 = oxide of P ion (i.e. P 2 O 5 )Base fraction (mol%)×2

[0159] The O / P ratio (R) is calculated by the formula D3: R=R1 / R2.

[0160] For example, the following comparative example A is used as an example. The contents of the oxide-based glass composition of the comparative example A are as follows: In terms of values ​​expressed in mol%, P 2 O 5 =53.59, Li 2 O=19.30、CuO=27.11。The amount of O contained in the molecular formula is: P 2 O 5 For 5, Li 2 O is 1, CuO is 1. The number of moles of O contained in the molecular formula is: P 2 O 5 is 267.95, Li 2 O is 19.30 and CuO is 27.11.

[0161] The O / P ratio of the glass of this example can be calculated as follows.

[0162] Find the molecular formula of glass: 53.59P 2 O 5 -19.30Li 2 O-27.11The number of O ions in CuO S The molecular formula of glass refers to a composition formula of glass expressed so that the total of molecules contained in the glass is 100.

[0163] That is, the number of O ions (P 2 O 5 :5,Li 2 O: 1, CuO: 1), in N S =53.59×5+19.30×1+27.11×2=314.36 Calculate N S .

[0164] For the glass of the above example, in the molecular formula of the glass, the number of O ions replaced by other anions is zero. S = 314.36 divided by P 2 O 5 The number of moles of P contained in is 53.59×2, and the O / P ratio is calculated as 314.36 / (53.59×2)=2.93….

[0165] O / P ratio calculation method 2

[0166] When one or more anion components other than oxygen are detected by analysis based on a known method, the oxygen content can be the following content (unit: anion %): the content calculated by the following method (3) from (1) the content of cations based on the valence of the cationic components contained in the glass and the molar % of the elements, and (2) the content of anions based on the valence of the anionic components other than oxygen and the molar % of the elements.

[0167] That is, according to the results of identification and quantitative analysis based on known methods,

[0168] (1) Regarding the cation components contained in the glass, the total cation content U is calculated based on the number of oxygen y and the number of cations x in the oxide MxOy, the number of oxygens per cation y / x×the mole % of the element.

[0169] (2) Regarding anion components other than oxygen, the total V of "the content of anions based on the molar % of the element × the average number of oxygen substituted per anion z / 2" is calculated based on the results of identification and quantitative analysis based on known methods and the valence z of the anions.

[0170] (3) UV may also be used as the content ratio of O ions to P ions.

[0171] As calculation examples of calculation method 2, the following calculation examples 1 and 2 are shown.

[0172] Calculation Example 1: When the molar percentages of P ions, Li ions, and Cu ions are 22.0, 8.0, and 5.5 (the content of the elements expressed in mole %), the corresponding oxides are: P 2 O 5 , Li 2 The y / x of O and CuO are 2.5, 0.5, and 1.0 respectively, therefore, U=22×2.5+8×0.5+5.5×1.0=64.5, and V=0.

[0173] Therefore, the molar percentage of O ions based on the molar percentage of the element is 64.5 (the content of the element expressed in mol %).

[0174] Based on the ratio of the value of O ions thus determined and the molar percentage of P ions analyzed, it can be determined that O / P ratio = 64.5 / 22 = 2.93…

[0175] Calculation Example 2: When the molar percentage of P ions, Li ions, and Cu ions is 22.0, 8.0, and 5.5 (the content of the elements expressed in mole %), and the molar percentage of F ions is 4.0 (the content of the elements expressed in mole %), the corresponding oxide is: P 2 O 5 , Li 2 The y / x of O and CuO are 2.5, 0.5, and 1.0 respectively, and the valence of F is -1. Therefore, U=22×2.5+8×0.5+5.5×1.0=64.5, and V=4×1 / 2=2.

[0176] Therefore, the molar percentage of O ions based on the molar percentage of the element is 62.5 (the content of the element expressed in mol %).

[0177] Based on the ratio of the value of O ions thus determined and the molar percentage of P ions analyzed, it can be determined that O / P ratio = 62.5 / 22 = 2.84…

[0178] In Glasses 1 to 6, the ratio of the O ion content to the P ion content (O / P ratio) is 3.15 or less from the viewpoint of achieving both improved transmittance in the visible region and improved near-infrared shielding capability and improved thermal stability of the glass.

[0179] In glasses 1 to 6, the O / P ratio is preferably 3.14 or less, and more preferably 3.13 or less, 3.12 or less, 3.11 or less, 3.10 or less, 3.09 or less, 3.08 or less, 3.07 or less, 3.06 or less, 3.05 or less, 3.04 or less, 3.03 or less, 3.02 or less, 3.01 or less, and 3.00 or less.

[0180] On the other hand, from the viewpoint of improving weather resistance and / or suppressing a decrease in solubility, a larger O / P ratio is preferred in Glass 1 to Glass 6. From this viewpoint, in Glass 1 to Glass 6, the O / P ratio is preferably 2.50 or more, and more preferably in the order of 2.60 or more, 2.65 or more, 2.70 or more, 2.73 or more, 2.75 or more, 2.77 or more, 2.80 or more, 2.81 or more, 2.82 or more, 2.83 or more, 2.84 or more, 2.85 or more, 2.86 or more, 2.87 or more, 2.88 or more, 2.89 or more, and 2.90 or more.

[0181] (Cationic component)

[0182] Glasses 1 to 6 contain four or more main cations selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions, and contain P ions, Li ions, and Cu ions as essential cations. In the oxide-based glass compositions (molar basis) of Glasses 1 to 6, the total content of the oxides of the above main cations is 90.0% or more.

[0183] In glasses 1 to 6, the total content of the oxides of the main cations is 90.0% or more, which can help improve the thermal stability of the glass, and / or can help improve the optical homogeneity of the glass by suppressing striae, volatilization, etc. From the above aspects, the total content of the oxides of the main cations in glasses 1 to 6 is preferably 92.0% or more, and more preferably in the order of 93.0% or more, 95.1% or more, 96.1% or more, 97.1% or more, 98.1% or more, 98.6% or more, 99.1% or more, and 99.6% or more, and can also be 100%. In one embodiment, the total content of the oxides of the main cations in glasses 1 to 6 can also be 100% or less, or 99.5% or less, 99% or less, 98.5% or less, 98.0% or less, or 97.5% or less.

[0184] Hereinafter, the content of the cationic component will be described based on the content in the glass composition (molar basis) on an oxide basis.

[0185] CuO is an essential component for imparting near-infrared shielding capability to glass, and therefore, Glasses 1 to 6 contain Cu ions as essential cations.

[0186] In glass 1, the CuO content is α 1 % or more. 1 It is a value calculated by the following formula 1.

[0187] (Formula 1)

[0188] α 1 =70400×exp(-2.855×R)

[0189] In Formula 1, R is the O / P ratio.

[0190] In addition, regarding Glass 2, the lower limit of the CuO content is defined by the following formula 2 from the CuO content per molar volume of glass.

[0191] (Formula 2)

[0192] C-3200×exp(-2.278×R)≥0

[0193] In Formula 2, C is the CuO content per molar volume of glass (unit: mmol / cc), and R is the O / P ratio.

[0194] In Formula 2, the above C is obtained by the following method.

[0195] The specific gravity of the glass is measured D (g / cc), and based on the glass composition obtained by analysis as described above, the mass equivalent to 1 mole of the glass composition, that is, the molar molecular weight M (g / mole), is calculated, and the molar volume of the glass M / D (unit: cc / mole) is calculated, and then C is calculated as C = molar % of CuO / (M / D) × 1000 (unit: mmol / cc).

[0196] The above-mentioned molar molecular weight M can be calculated as follows:

[0197] Based on the description of the above-mentioned oxide-based glass composition, the formula weight of the oxide corresponding to the above-mentioned cation component Ai is set to MA i , the anion component B k The atomic weight is MB k , and the atomic weight of oxygen is set to Mo, and M={Σ(PA i ×MA i )+Σ(PB k ×MB k )-Σ(N k / 2)Mo} / ΣPA i Calculate the above molar molecular weight M.

[0198] For example, the glass composition is composed of s mol% of A on an oxide basis. 2 O component, t mol % of BO component and u mol % of F component on an oxide basis, s+t+u=100(%), A 2 The formula weight of the O component is M A (g / mole), the formula weight of BO component is M B (g / mole), the atomic weight of F is M F (g / mole), and the atomic weight of oxygen is M O (g / mole),

[0199] M=(s×M A +t×M B +u×M F -u / 2×M O ) / (s+t).

[0200] For example, in Comparative Example A described below (the content expressed in mol % in the oxide-based glass composition is: 2 O 5 =53.59,Li 2O=19.30, CuO=27.11) can be used

[0201] P 2 O 5 Formula weight: 141.94 (g / mole)

[0202] Li 2 Formula weight of O: 29.88 (g / mole)

[0203] Formula weight of CuO: 79.55 (g / mole),

[0204] It was calculated that M = (53.59 x 141.94 + 19.30 x 29.88 + 27.11 x 79.55) / (53.59 + 19.30 + 27.11) = 103.40 (g / mole).

[0205] The inventors have repeatedly conducted in-depth studies and have newly discovered the following results: if the O / P ratio is reduced in a glass mainly composed of O ions as anions, the absorption of CuO in the red region shifts to the long wavelength side, thereby suppressing the reduction in transmittance in the red region and increasing the CuO content. In addition, the inventors have newly discovered that there is a good correlation between the O / P ratio and the CuO content for achieving a given half value with a given thickness. For glass 2 having an O / P ratio in the range described above, the lower limit of the CuO content (α) is defined by Formula 1. 1 , α 2 ), for glass 5, the lower limit of the CuO content (α 1 , α 2 ). In addition, for glasses having an O / P ratio in the range described above, the CuO content per molar volume of the glass is specified by Formula 2, and for glass 6, the CuO content per molar volume of the glass is specified by Formula 6.

[0206] In glass 3, based on A calculated by the following formula 3 1 To specify the CuO content, A 1 More than 2500.

[0207] (Formula 3)

[0208] A 1 ={O(P)-O(others)}×Cu

[0209] In Formula 3, O(P) represents the amount of oxygen in the oxide that constitutes the P ion in the glass composition on an oxide basis, O(others) represents the amount of oxygen in the glass composition on an oxide basis after removing the above O(P) from the amount of oxygen in the oxide of the main cations shown previously constituting Glass 3, and Cu represents the CuO content on a molar basis in the glass composition on an oxide basis.

[0210] "O(P)" in Formula 3 is calculated as follows.

[0211] In the oxide-based glass composition (molar basis), P 2 O 5 When the content is M mol%, P 2 O 5 The number of oxygen contained in the chemical formula is 5, and O(P) is calculated as “O(P)=M×5”.

[0212] Similarly, for the main cations other than P ions, the amount of oxygen constituting the oxide of each cation is calculated using the value of the content in terms of oxide in the glass composition (molar basis) based on the oxide and the amount of oxygen contained in the oxide formed by each cation in a formal valence state.

[0213] “O(others)” is calculated from the value obtained by subtracting O(P) from the total amount of oxygen calculated for the oxides of the main cations in this manner.

[0214] When the CuO content is N mol % in the oxide-based glass composition (molar basis), A 1 ={O(P)-O(others)}×N to calculate "A 1 ”.

[0215] As described above, the present inventors have newly discovered the following result: if the O / P ratio is reduced in a glass mainly composed of O ions as anions, the absorption of CuO in the red region shifts to the long wavelength side, thereby suppressing the decrease in transmittance in the red region and increasing the CuO content. In addition, the following new insight has been obtained: by forming chemical species other than PO coordinated to CuO with chemical species having a smaller ionic radius and a smaller valence, according to the following 1) and 2), the transmittance in the visible region (purple region to red region) can be increased. Regarding glass 3, based on the above insight, based on A calculated by formula 3 1 To specify the CuO content.

[0216] 1) By making the 2+ The absorption of longer wavelengths can increase the transmittance in the red region.

[0217] 2) Since the glass can be made into a liquid phase at low temperature, the absorption of Cu in the purple region around 400 nm can be suppressed. + The production of.

[0218] Regarding glass 3, from the perspective of achieving both improved transmittance in the visible region and improved near-infrared shielding capability, A 1 The molecular weight of the present invention is 2500 or more, preferably 2800 or more, and more preferably 2900 or more, 3000 or more, 3100 or more, 3200 or more, 3300 or more, 3400 or more, 3500 or more, 3600 or more, 3700 or more, 3800 or more, 3900 or more, 4000 or more, 4100 or more, 4200 or more, 4300 or more, 4400 or more, 4500 or more, 4600 or more, 4700 or more, 4800 or more, 4900 or more, 5000 or more, 5100 or more, 5200 or more, 5300 or more, 5400 or more, 5500 or more, 5600 or more, 5700 or more, 5800 or more, 5900 or more, 6000 or more, 6100 or more, 6200 or more, 6300 or more, 6400 or more, and 6500 or more in this order. On the other hand, from the viewpoint of further suppressing the decrease in thermal stability of the glass caused by the large amount of Cu and O, the decrease in transmittance at the desired half-value wavelength, and / or the decrease in thermal stability or weather resistance of the glass caused by too little O (others), A 1 It is preferably 20000 or less, more preferably 19000 or less, 18000 or less, 17000 or less, 16000 or less, 15000 or less, 14000 or less, 13000 or less, 12000 or less, 11000 or less, 10000 or less, 9000 or less, or 8000 or less. It should be noted that in order to achieve a desired half value with a thinner thickness, there is a tendency to prefer a larger value.

[0219] In glass 4, based on A calculated by the following formula 4 2 To specify the CuO content, A 2 More than 700.

[0220] (Formula 4)

[0221] A 2 ={O(P)-O(others)}×C

[0222] In Formula 4, C is the CuO content per molar volume of glass (unit: millimole / cc). O(P) represents the amount of oxygen in the oxide constituting the P ion in the glass composition based on the oxide, and O(others) represents the amount of oxygen after removing the above O(P) from the amount of oxygen in the oxide constituting the above main cation in the glass composition based on the oxide.

[0223] Regarding glass 4, from the perspective of achieving both improved transmittance in the visible region and improved near-infrared shielding capability, A 2 The A is 700 or more, preferably 800 or more, and more preferably 850 or more, 890 or more, 1000 or more, 1100 or more, 1200 or more, 1300 or more, 1400 or more, 1500 or more, 1600 or more, 1700 or more, and 1800 or more. On the other hand, from the viewpoint of further suppressing the decrease in thermal stability of the glass caused by the large amount of Cu and O, the decrease in transmittance at the desired half-value wavelength, and / or the decrease in thermal stability or weather resistance of the glass caused by too little O (others), A 2 It is preferably 5000 or less, more preferably 4000 or less, 3500 or less, 3000 or less, 2500 or less, or 2000 or less. In order to achieve a desired half-value of transmittance with a thinner thickness, a larger value tends to be preferred.

[0224] In addition, in glass 5, the CuO content is α 2 % or more. 2 It is a value calculated by the following formula 5.

[0225] (Formula 5)

[0226] α 2 =76522×exp(-2.855×R)

[0227] In Formula 5, R is the O / P ratio.

[0228] In addition, regarding Glass 6, the lower limit of the CuO content is defined by the following Formula 6 based on the CuO content per molar volume of glass.

[0229] (Formula 6)

[0230] C-3478×exp(-2.278×R)≥0

[0231] In Formula 6, C is the CuO content per molar volume of glass (unit: mmol / cc), and R is the O / P ratio.

[0232] The CuO content of glasses 1 to 6 is preferably 4.0% or more in the glass composition based on oxide (molar basis), and is more preferably 5.0% or more, 6.0% or more, 7.0% or more, 7.5% or more, 8.0% or more, 8.5% or more, 9.0% or more, 9.5% or more, 10.0% or more, 10.5% or more, 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more in this order. From the viewpoint of leaving room for introducing glass-forming components and maintaining the thermal stability of the glass, the CuO content is preferably 48.0% or less, and more preferably 47.0% or less, 46.0% or less, 45.0% or less, 44.0% or less, 43.5% or less, 43.0% or less, 42.5% or less, 42.0% or less, 41.5% or less, 41.0% or less, 40.5% or less, 40.0% or less, 39.5% or less, 39.0% or less, 38.5% or less, 38.0% or less, 37.5% or less, 37.0% or less, 36.5% or less, 36.0% or less, 35.5% or less, 35.0% or less, 34.5% or less, 34.0% or less, 33.5% or less, 33.0% or less, 32.5% or less, 32.0% or less, 31.5% or less, and 31.0% or less.

[0233] As the transmittance characteristics converted to a thickness of 0.11 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, and the CuO content in the oxide-based glass composition (molar basis) is preferably 15.0% or more, and more preferably 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more.

[0234] As the transmittance characteristics converted to a thickness of 0.21 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% is T50 is in the range of 600nm to 650nm, and the CuO content in the oxide-based glass composition (molar basis) is preferably 10.0% or more, and more preferably 10.5% or more, 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more in the order of more preferably.

[0235] As the transmittance characteristics converted to a thickness of 0.25 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, and the CuO content in the oxide-based glass composition (molar basis) is preferably 10.0% or more, and more preferably 10.5% or more, 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more in the order of more preferably.

[0236] On the other hand, regarding the transmittance characteristics converted to a thickness of 0.25 mm, if the CuO content becomes large, the wavelength λ at which the external transmittance including the reflection loss reaches 50% is T 50 may be lower than 600nm, and therefore, the CuO content is preferably less than 35.0%, and more preferably in the order of less than 34.0%, less than 33.0%, less than 32.0%, less than 31.0%, less than 30.0%, less than 29.5%, less than 29.0%, less than 28.5%, less than 28.0%, less than 27.5%, less than 27.0%, less than 26.5%, less than 26.0%, less than 25.5%, less than 25.0%, less than 24.5%, less than 24.0%, less than 23.5%, less than 23.0%, less than 22.5%, less than 22.0%, less than 21.5%, less than 21.0%, less than 20.5%, and less than 20.0%.

[0237] In order to make the external transmittance including reflection loss reach 50% at wavelengths above 550nm, the wavelength λ TThe thickness of the glass having an oxide content of 50 to 645 nm is less than 0.25 mm, and the CuO content in the glass composition based on oxide (molar basis) is preferably 10.0% or more, and more preferably 10.5%, 11.0%, 11.5%, 12.0%, 12.5%, 13.0%, 13.5%, 14.0%, 14.5%, 15.0%, 15.5%, 16.0%, 16.5%, 17.0%, 17.5%, 18.0%, 18.5%, 19.0%, 19.5%, and 20.0% or more.

[0238] In order to make the external transmittance including reflection loss reach 50% at wavelengths above 550nm, the wavelength λ T The thickness of the glass having an oxide content of 50 or more and a molecular weight of 633 nm or more is less than 0.25 mm, and the CuO content in the glass composition based on oxide (molar basis) is preferably 10.5% or more, and more preferably 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more.

[0239] In glass 2 and glass 4, the value of C is preferably greater than 3.0, and more preferably in the order of greater than 3.1, greater than 3.3, greater than 3.5, greater than 3.7, greater than 3.9, greater than 4.0, greater than 4.1, greater than 4.2, greater than 4.3, greater than 4.4, greater than 4.5, greater than 4.6, greater than 4.7, greater than 4.8, greater than 4.9, greater than 5.0, greater than 5.1, greater than 5.2, greater than 5.3, greater than 5.4, and greater than 5.5. From the viewpoint of leaving room for the introduction of glass-forming components and maintaining the thermal stability of the glass, the value of C is preferably 16.0 or less, and further preferably 15.0 or less, 14.0 or less, 13.5 or less, 13.0 or less, 12.5 or less, 12.0 or less, 11.9 or less, 11.8 or less, 11.7 or less, 11.6 or less, 11.5 or less, 11.4 or less, 11.3 or less, 11.2 or less, 11.1 or less, 11.0 or less, 10. The order of less than 9, less than 10.8, less than 10.7, less than 10.6, less than 10.5, less than 10.4, less than 10.3, less than 10.2, less than 10.1, less than 10.0, less than 9.9, less than 9.8, less than 9.7, less than 9.6, less than 9.5, less than 9.4, less than 9.3, less than 9.2, less than 9.1, less than 9.0, less than 8.9, less than 8.8, less than 8.7, less than 8.6, and less than 8.5 is more preferred.

[0240] In glasses 1 to 6, the CuO content can be α 3 % or more. 3 It is a value calculated by the following formula 7.

[0241] (Formula 7)

[0242] α 3 =(70400×0.25 / d)×exp(-2.855×R)

[0243] In formula 7, R is the O / P ratio. d can take a value greater than 0 and less than 0.25. For example, d can be 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.01, etc. However, the value of d is not limited to these values. In order to achieve the desired transmittance half value with a thinner thickness, there is a tendency to prefer a smaller value of d.

[0244] For example, when d = 0.11, the CuO content can be α 3 % or more, α 3 The calculation is performed by the following formula.

[0245] α 3 =(70400×0.25 / 0.11)×exp(-2.855×R)

[0246] In glass, when the external transmittance of light with a wavelength of 633 nm reaches 50%, the thickness of the glass is D (mm), in one embodiment, d=D in the above formula 7. In this case, α 3 The calculation is performed by the following formula.

[0247] α 3 =(70400×0.25 / D)×exp(-2.855×R)

[0248] Regarding Glasses 1 to 6, the lower limit of the CuO content may be a value defined by the following formula 8 based on the CuO content per molar volume of glass.

[0249] (Formula 8)

[0250] C-3200×0.25 / d×exp(-2.855×R)≥0

[0251] In formula 8, d can take a value greater than 0 and less than 0.25. For example, d can be 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.01, etc. However, the value of d is not limited to these values. In order to achieve the desired transmittance half value with a thinner thickness, there is a tendency to prefer a smaller value of d.

[0252] For example, when d=0.11, Formula 8 is as follows.

[0253] C-3300×0.25 / 0.11×exp(-2.855×R)≥0

[0254] In glass, when the thickness of the glass when the external transmittance for light of a wavelength of 633 nm reaches 50% is D (mm), in one embodiment, d=D can be satisfied in the above formula 8.

[0255] Regarding the CuO content, each of the glasses 1 to 6 may satisfy one or more of the regulations in the formula related to the other glasses.

[0256] Glasses 1 to 6 contain P ions as essential cations. As described above, from the perspective of achieving both improved transmittance in the visible region and improved near-infrared shielding capability, a lower O / P ratio is preferred. In order to reduce the O / P ratio, it is preferred to increase the P2 O 5 From this point of view, the glass composition (molar basis) based on oxides contains P 2 O 5 The content is preferably 33.0% or more, and more preferably 34.0% or more, 35.0% or more, 36.0% or more, 37.0% or more, 38.0% or more, 39.0% or more, 40.0% or more, 40.5% or more, 41.0% or more, 41.5% or more, 42.0% or more, 42.5% or more, 43.0% or more, 43.5% or more, 44.0% or more, 44.5% or more, 45.0% or more, 45.5% or more, 46.0% or more, 46.5% or more, 47.0% or more, 47.5% or more, 48.0% or more, 48.5% or more, 49.0% or more, 49.5% or more, and 50.0% or more. 2 O 5 Since CuO itself does not have near-infrared absorbing ability, from the viewpoint of increasing the content of CuO having near-infrared absorbing ability, P 2 O 5 The content is preferably 72.0% or less, and more preferably in the order of 71.0% or less, 70.0% or less, 69.5% or less, 69.0% or less, 68.5% or less, 68.0% or less, 67.5% or less, 67.0% or less, 66.5% or less, 66.0% or less, 65.5% or less, 65.0% or less, 64.5% or less, 64.0% or less, 63.5% or less, 63.0% or less, 62.5% or less, 62.0% or less, 61.5% or less, 61.0% or less, 60.5% or less, and 60.0% or less. In addition, from the viewpoint of further suppressing the decrease in weather resistance and / or suppressing the decrease in solubility, P is also preferably 2 O 5 The content is less than the above value.

[0257] In order to obtain the desired transmittance characteristics, it is desirable that the oxide-based glass composition of the above-mentioned glass mainly consists of P 2 O 5 , Li 2 O and CuO. From this point of view, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2The above glass contains P ions, Li ions and Cu ions as essential cations, and further contains one or more cations selected from the group of main cations in order to obtain the thermal stability of the glass and / or the chemical durability of the glass. Therefore, the total content (P 2 O 5 +Li 2 O+CuO) is less than 100%, preferably less than 99.9%, and more preferably less than 99.8%, less than 99.7%, less than 99.6%, less than 99.5%, less than 99.4%, less than 99.2%, less than 99.0%, less than 98.0%, less than 97.0%, less than 96.0%, less than 95.0%, less than 94.0%, less than 93.0%, less than 92.0%, less than 91.0%, less than 90.0%, less than 89.0%, less than 88.0%, less than 87.0%, less than 86.0%, and less than 85.0%.

[0258] In one embodiment, as the transmittance characteristic converted to a thickness of 0.11 mm, the wavelength λ at which the external transmittance including the reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 O + CuO) in the oxide-based glass composition (molar basis) is preferably 84.0% or more, and more preferably 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more in this order.

[0259] As the transmittance characteristics converted to a thickness of 0.21 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2The content of MgO (O+CuO) in the glass composition based on oxides (molar basis) is preferably 80.0% or more, and more preferably 81.0% or more, 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more.

[0260] As the transmittance characteristics converted to a thickness of 0.25 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 The content of MgO (O+CuO) in the glass composition based on oxides (molar basis) is preferably 75.0% or more, and more preferably 76.0% or more, 77.0% or more, 78.0% or more, 79.0% or more, 80.0% or more, 81.0% or more, 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more in this order.

[0261] In order to make the external transmittance including reflection loss reach 50% at wavelengths above 550nm, the wavelength λ T 50 The thickness of the glass reaching 645nm is less than 0.25mm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 The content of MgO (O+CuO) in the glass composition based on oxides (molar basis) is preferably 80.0% or more, and more preferably 81.0% or more, 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more.

[0262] In order to make the external transmittance including reflection loss reach 50% at wavelengths above 550nm, the wavelength λ T 50 The thickness of the glass reaching 633nm is less than 0.25mm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li2 The content of MgO (O+CuO) in the glass composition based on oxides (molar basis) is preferably 81.0% or more, and more preferably 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more in this order.

[0263] As glass that conforms to one embodiment described above, glasses of Examples 1 to 60 described below are mentioned.

[0264] On the other hand, as another aspect, the total content of MgO, CaO, SrO, BaO and ZnO (MgO+CaO+SrO+BaO+ZnO) relative to Li 2 O、Na 2 O and K 2 Total content of O (Li 2 O+Na 2 O+K 2 O) molar ratio ((MgO+CaO+SrO+BaO+ZnO) / (Li 2 O+Na 2 O+K 2 For glass with a transmittance of 2.0 or more, as a transmittance characteristic converted to a thickness of 0.11 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 O + CuO) in the oxide-based glass composition (molar basis) is preferably 65.0% or more, and more preferably 66.0% or more, 67.0% or more, 68.0% or more, 69.0% or more, and 70.0% or more in this order.

[0265] Regarding the above-mentioned other aspect, as the transmittance characteristic converted to a thickness of 0.21 mm, the wavelength λ at which the external transmittance including the reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2O + CuO) in the oxide-based glass composition (molar basis) is preferably 60.0% or more, and more preferably 61.0% or more, 62.0% or more, 63.0% or more, 64.0% or more, and 65.0% or more in this order.

[0266] Regarding the above-mentioned other aspect, as the transmittance characteristic converted to a thickness of 0.25 mm, the wavelength λ at which the external transmittance including the reflection loss reaches 50% is T 50 is in the range of 600nm to 650nm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 O + CuO) in the oxide-based glass composition (molar basis) is preferably 55.0% or more, and more preferably 56.0% or more, 57.0% or more, 58.0% or more, 59.0% or more, and 60.0% or more in this order.

[0267] Regarding the above-mentioned other embodiment, in order to make the external transmittance including reflection loss reach 50% at a wavelength λ of 550 nm or more T 50 The thickness of the glass reaching 645nm is less than 0.25mm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 O + CuO) in the oxide-based glass composition (molar basis) is preferably 60.0% or more, and more preferably 61.0% or more, 62.0% or more, 63.0% or more, 64.0% or more, and 65.0% or more in this order.

[0268] Regarding the above-mentioned other embodiment, in order to make the external transmittance including reflection loss reach 50% at a wavelength λ of 550 nm or more T 50 The thickness of the glass reaching 633nm is less than 0.25mm, P 2 O 5 , Li 2 The total content of O and CuO (P 2 O 5 +Li 2 O + CuO) in the oxide-based glass composition (molar basis) is preferably 61.0% or more, and more preferably 62.0% or more, 63.0% or more, 64.0% or more, 65.0% or more, and 66.0% or more in this order.

[0269] Examples of glass that conforms to another embodiment described above include Examples 61 to 66 described below.

[0270] For glasses 3 and 4, the group of main cations described above includes B ions and Si ions. On the other hand, for glasses 1, 2, 5, and 6, the group of main cations described above does not include B ions and Si ions that tend to increase the melting temperature. In one embodiment, from the viewpoint of improving the near-infrared shielding ability of the glass and improving the transmittance in the visible region, glasses 1 to 6 may be glasses containing one or both of B ions and Si ions that tend to shift the half-value to the short wavelength side, and in another embodiment, may be glasses containing neither B ions nor Si ions.

[0271] Regarding Glass 1 and Glass 2, from the viewpoint of improving the transmittance in the visible region, in the oxide-based glass composition (molar basis), B 2 O 3 With SiO 2 Total content (B 2 O 3 +SiO 2 ) is 3.0% or less, preferably 2.5% or less, and more preferably in the order of 2.0% or less, 1.5% or less, 1.0% or less, and 0.5% or less.

[0272] In order to further improve the transmittance in the visible region, glasses 3 to 6 have a glass composition based on oxides (on a molar basis) of B 2 O 3 With SiO 2 Total content (B 2 O 3 +SiO 2 ) is preferably 3.0% or less, and more preferably 2.5% or less, 2.0% or less, 1.5% or less, 1.0% or less, and 0.5% or less in this order.

[0273] In glasses 1 to 6, B 2 O 3 With SiO 2 Total content (B 2 O 3 +SiO 2 ) can be 0%, above 0% or more than 0%.

[0274] In glasses 1 to 6, from the viewpoint of further improving the transmittance in the visible region, B 2 O 3 The content of B is preferably 3.0% or less, and more preferably 2.5% or less, 2.0% or less, 1.5% or less, 1.0% or less, and 0.5% or less in this order. 2 O3 The content may be 0%.

[0275] On the other hand, for Glasses 1 to 6, when the glasses were roughly melted in a quartz crucible in order to promote homogenization of the glasses, SiO 2 The content is preferably more than 0%, and more preferably in the order of 0.01% or more, 0.02% or more, 0.03% or more, 0.04% or more, 0.05% or more, 0.1% or more, 0.2% or more, and 0.3% or more. However, when excessive SiO is introduced into the glass, 2 There is a tendency to reduce the optical homogeneity of the glass. From this point of view, in Glasses 1 to 6, SiO 2 The content is preferably 2.0% or less, and more preferably 1.4% or less, 0.9% or less, 0.8% or less, 0.6% or less, and 0.4% or less in this order.

[0276] Glasses 1 to 6 contain Li ions as essential cations. 2 Compared with various glass components, O has a higher ability to maintain CuO absorption in the long wavelength range and has less adverse effect on weather resistance. 2 The O content is preferably 0.1% or more, and more preferably 0.5% or more, 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, 7.0% or more, 7.5% or more, and 8.0% or more. On the other hand, from the viewpoint of ensuring the thermal stability of the glass and / or further suppressing the decrease in weather resistance, Li 2 The O content is preferably 35.0% or less, and more preferably 34.0% or less, 33.0% or less, 32.0% or less, 31.0% or less, 30.0% or less, 29.5% or less, 29.0% or less, 28.5% or less, 28.0% or less, 27.5% or less, 27.0% or less, 26.5% or less, 26.0% or less, 25.5% or less, 25.0% or less, 24.5% or less, 24.0% or less, 23.5% or less, 23.0% or less, 22.5% or less, 22.0% or less, 21.5% or less, 21.0% or less, 20.5% or less, and 20.0% or less.

[0277] In Glasses 1 to 6, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3) is 8.0% or less, preferably 7.5% or less, and more preferably in the order of 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.8% or less, 1.6% or less, 1.5% or less, and 1.4% or less, and may be 0%. On the other hand, from the viewpoint of improving the weather resistance of glass and improving the mechanical strength of glass, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) may exceed 0%, preferably be more than 0.1%, and more preferably be in the order of more than 0.2%, more than 0.3%, more than 0.4%, more than 0.5%, more than 0.6%, more than 0.7%, more than 0.8%, more than 0.9%, more than 1.0%, more than 1.1%, more than 1.3%.

[0278] Al 2 O 3 Al is a component that can contribute to particularly improving weather resistance. 2 O 3 The content may be 0%, 0% or more, or more than 0%. From the viewpoint of improving weather resistance, it is preferably 0.1% or more, and more preferably in the order of 0.2% or more, 0.3% or more, 0.4% or more, 0.5% or more, 0.6% or more, 0.7% or more, 0.9% or more, 1.1% or more, 1.3% or more, and 1.5% or more. On the other hand, from the viewpoint of further suppressing the decrease in transmittance in the visible region, Al 2 O 3 The content is preferably 8.0% or less, and more preferably in the order of 7.5% or less, 7.0% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, and 2.5% or less. In one embodiment, from the viewpoint of giving priority to the improvement of the near-infrared absorption characteristics over the maintenance of the weather resistance of the glass, and further improving the transmittance in the visible region by suppressing the absorption of CuO from shifting to the short wavelength side, and improving the near-infrared absorption characteristics, Al 2 O 3 The content is preferably less than 2.0%, and is more preferably in the order of 1.9% or less, 1.8% or less, 1.7% or less, 1.6% or less, 1.5% or less, 1.4% or less, 1.3% or less, 1.2% or less, 1.1% or less, 1.0% or less, 0.9% or less, 0.8% or less, 0.7% or less, 0.6% or less, and 0.5% or less.

[0279] MgO is a component that can be appropriately added based on the reason of adjusting the thermal stability of the glass, but since it can shift the absorption of CuO to the short wavelength side, there is a tendency that it is difficult to increase the CuO content. In addition, the solubility of the glass tends to decrease with the increase of the MgO content. From these viewpoints, the MgO content is preferably 9.0% or less, and more preferably in the order of 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.0% or less, 3.0% or less, and 2.0% or less. The MgO content can also be 0%. In one embodiment, from the viewpoint of improving the mechanical strength of the glass, the MgO content can exceed 0%, preferably 0.5% or more, and more preferably 1.0% or more.

[0280] La 2 O 3 It is a component that can help improve weather resistance without impairing the near-infrared absorption properties of glass. 2 O 3 The content is preferably 0.10% or more, more preferably 0.15% or more, 0.18% or more, and 0.21% or more in this order. On the other hand, from the viewpoint of further suppressing the decrease in transmittance in the visible region, La 2 O 3 The content is preferably 8.0% or less, and more preferably in the order of 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.5% or less, and 1.0% or less.

[0281] Y 2 O 3 It is also a component that can help improve weather resistance without impairing the near-infrared absorption properties of glass. 2 O 3 The content is preferably 0.10% or more, and more preferably 0.15% or more, 0.20% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, 0.45% or more, and 0.50% or more. On the other hand, from the viewpoint of further suppressing the decrease in transmittance in the visible region, Y 2 O 3 The content is preferably 8.0% or less, and more preferably in the order of 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.5% or less, and 1.0% or less. It should be noted that from the viewpoint of increasing the molar volume of the glass without increasing the specific gravity of the glass, Y can also be introduced. 2 O 3 .

[0282] G 2 O 3 It is also a component that can help improve weather resistance. 2 O 3 The content is preferably 0.10% or more, more preferably 0.15% or more, 0.18% or more, and 0.21% or more in this order. On the other hand, from the viewpoint of further suppressing the decrease in transmittance in the visible region, Gd 2 O 3 The content is preferably 8.0% or less, and more preferably in the order of 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.5% or less, and 1.0% or less.

[0283] It should be noted that the oxide-based glass composition may contain Lu 2 O 3 Sc 2 O 3 One or more of the rare earth oxides other than the above may not be contained. These components are generally expensive, so La 2 O 3 , Y 2 O 3 and Gd 2 O 3 The content of the rare earth oxides other than these (when two or more kinds are included, the total content thereof) is preferably 2.5% or less, preferably 1.5% or less, 1.0% or less, 0.5% or less, and may be 0%.

[0284] In Glasses 1 to 6, Al 2 O 3 ,La 2 O 3 , Y 2 O 3 and Gd 2 O 3 Total content (Al 2 O 3 +La 2 O 3 +Y 2 O 3 +Gd 2 O 3) is preferably 0.1% or more, and more preferably 0.15% or more, 0.20% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, 0.45% or more, and 0.50% or more in this order. On the other hand, from the viewpoint of ensuring the thermal stability of the glass and / or lowering the melting temperature, the total content (Al 2 O 3 +La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) is preferably 8.0% or less, and more preferably in the order of 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.5% or less, and 1.0% or less.

[0285] There is a tendency that cations with a formal valence of +2 do not play a prominent role in terms of improving transmittance in the visible region or weather resistance when observing the glass composition as a whole. Therefore, the total content of MgO, CaO, SrO and BaO, which are oxides of cations with a formal valence of +2, is less than that of Li ion, which is an essential cation. 2 The molar ratio of O content ((MgO+CaO+SrO+BaO) / Li 2 O) is preferably 2.0 or less, more preferably 1.5 or less, 1.3 or less, 1.2 or less, 1.1 or less, 1.0 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, or 0.2 or less. As described later, the above components are arbitrary components that can be used when adjusting the half value together with a part of the alkali component.

[0286] In addition, the total content of MgO, CaO, SrO, BaO and ZnO, which are oxides of cations with a formal valence of +2, is 2.3 times that of Li ions, which are essential cations, from the viewpoint of improving the transmittance in the visible region. 2 The molar ratio of O content ((MgO+CaO+SrO+BaO+ZnO) / Li 2 O) is preferably 2.0 or less, more preferably 1.5 or less, 1.3 or less, 1.2 or less, 1.1 or less, 1.0 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, or 0.2 or less. On the other hand, from the viewpoint of improving weather resistance, ((MgO+CaO+SrO+BaO+ZnO) / Li2 O) is preferably 2.0 or more, more preferably 2.5 or more, 3.0 or more, 3.5 or more, and 4.0 or more in this order. As described later, the above components are arbitrary components that can be used when adjusting the half value together with a part of the alkali component.

[0287] The BaO content is 0%, or may be 0% or more or more than 0%. BaO is a component that improves weather resistance by introducing a certain amount, and the change in T600 caused by the introduction is small. T600 will be described later. BaO can be added for the purpose of improving the thermal stability of the glass and adjusting the solubility. In addition, BaO can also be used to adjust the concentration of CuO. The BaO content is preferably 0.5% or more, and more preferably in the order of 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, and 7.0% or more. However, there is a tendency to reduce T400 due to excessive introduction. T400 will be described later. From the above viewpoints, the BaO content is preferably 36.0% or less, and more preferably 35.0% or less, 34.0% or less, 33.0% or less, 32.0% or less, 31.0% or less, 30.0% or less, 29.0% or less, 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, and 9.0% or less in this order.

[0288] The SrO content is 0%, and may be 0% or more or exceed 0%. Like BaO, SrO is a component that is relatively difficult to reduce weather resistance, and is a component that can be appropriately added for reasons such as adjusting the thermal stability of the glass. SrO can also be used to adjust the concentration of CuO. The SrO content is preferably 0.5% or more, and more preferably in the order of 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, and 7.0% or more. However, there is a tendency for T400 to decrease due to excessive introduction, and therefore the SrO content is preferably 30.0% or less, and more preferably 29.0% or less, 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, and 9.0% or less in this order.

[0289] The CaO content is 0%, and may be 0% or more or more than 0%. CaO is a component that is relatively difficult to reduce weather resistance, and is also a component that can be appropriately added for reasons such as thermal stability of the glass. CaO can also be used to adjust the concentration of CuO. The CaO content is preferably 0.5% or more, preferably 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, 7.0% or more. However, there is a tendency for T400 to decrease due to excessive introduction, and therefore the CaO content is preferably 30.0% or less, and more preferably 29.0% or less, 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, and 9.0% or less in this order.

[0290] Among the cations contained in the group of main cations described above, Na ions, K ions, and Zn ions tend to deteriorate the weather resistance of the glass, and therefore, it is difficult to freely use them in place of Li ions as essential cations. In addition to this, from the perspective of improving the transmittance in the visible region or near-infrared region, in Glasses 1 to 6, Na2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 The molar ratio (Na2O) is preferably 2.4 or less, more preferably 2.3 or less, and is more preferably 2.2 or less, 2.1 or less, 2.0 or less, 1.9 or less, 1.8 or less, 1.7 or less, 1.6 or less, 1.5 or less, 1.4 or less, 1.3 or less, 1.2 or less, 1.1 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, 0.2 or less, 0.1 or less, and 0.05 or less in this order, and may be 0.00. On the other hand, from the viewpoint of suppressing the raw material cost of the glass, the molar ratio (Na2O) is preferably 2.4 or less, more preferably 2.3 or less, and is more preferably 2.2 or less, 2.1 or less, 2.0 or less, 1.9 or less, 1.8 or less, 1.7 or less, 1.6 or less, 1.5 or less, 1.4 or less, 1.3 or less, 1.2 or less, 1.1 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, 0.2 or less, 0.1 or less, and 0.05 or less in this order. 2 O+K 2 O+ZnO) / Li 2 O) may be 0, 0 or more, or more than 0, and is preferably 0.05 or more, and may be 0.1 or more, 0.2 or more, or 0.3 or more, from the viewpoint of promoting the lowering of Tg and Tm described later by mixing a plurality of components.

[0291] In addition, the more Na ions, K ions, and Zn ions are present, the more difficult it is to introduce a large amount of P. 2 O 5 To maintain weather resistance, the result is that it is more difficult to introduce the desired amount of P 2 O 5 From the above viewpoints and the viewpoint of suppressing the decrease of weather resistance as mentioned above, Na 2 O.K 2 Total content of O and ZnO (Na 2 O+K 2 The total content (Na2O3+ZnO) is preferably 30.0% or less, and is more preferably 25.0% or less, 20.0% or less, 15.0% or less, 12.0% or less, 10.0% or less, 9.0% or less, 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.0% or less, 3.0% or less, 2.0% or less, and 1.0% or less. The above total content may also be 0%. On the other hand, from the viewpoint of suppressing the raw material cost of glass, the total content (Na2O3+ZnO) is preferably 30.0% or less, and is more preferably 25.0% or less, 20.0% or less, 15.0% or less, 12.0% or less, 10.0% or less, 9.0% or less, 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.0% or less, 3.0% or less, 2.0% or less, and 1.0% or less. 2 O+K 2 O+ZnO) can also be 1.0% or more, 2.0% or more, 3.0% or more, or 5.0% or more.

[0292] Na 2 The O content may be 0%, 0% or more, or more than 0%. 2O also tends to reduce heat resistance if introduced in excess. 2 The O content is preferably 20.0% or less, and more preferably 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, 9.0% or less, and 8.0% or less. On the other hand, Na 2 O is an easily available and low-cost raw material, and can be appropriately added to improve solubility. 2 The O content may be, for example, 0.5% or more, or further may be 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, or 5.0% or more.

[0293] K 2 The O content may be 0%, 0% or more, or more than 0%. 2 O also tends to reduce weather resistance due to excessive introduction. In addition, there is a tendency to shorten the absorption wavelength of CuO, so it is not desirable to introduce it actively. From these viewpoints, K 2 The O content is preferably 20.0% or less, and more preferably 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, 9.0% or less, and 8.0% or less. On the other hand, K can be appropriately added. 2 O improves the solubility of the glass. From this point of view, K 2 The O content is preferably 0.2% or more, and more preferably in the order of 0.5% or more, 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, and 5.0% or more.

[0294] Cs 2 The O content may be 0%, 0% or more, or more than 0%. 2 O also tends to reduce weather resistance, so it is not desirable to actively introduce it. 2 The O content is preferably 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, 9.0% or less, 8.0% or less, 7.0% or less, and 6.0% or less. On the other hand, in order to adjust thermal stability and solubility, Cs 2 The O content may be 0.5% or more, or may be 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more,

[0295] From the perspective of improving the solubility of glass, Li 2 O、Na 2 O and K 2 Total content of O (Li 2 O+Na 2 O+K 2 O) is preferably 1.8% or more, and more preferably in the order of 2.1% or more, 2.3% or more, 2.5% or more, 3.5% or more, 4.5% or more, 5.5% or more, 6.5% or more, 7.5% or more, 8.5% or more, 9.5% or more, 10.0% or more, and 10.5% or more.

[0296] On the other hand, from the viewpoint of further suppressing the decrease in weather resistance, the total content (Li 2 O+Na 2 O+K 2 The total content (Li O) is preferably 35.0% or less, and is more preferably 33.5% or less, 32.5% or less, 31.5% or less, 30.5% or less, 29.5% or less, 28.5% or less, 27.5% or less, 26.5% or less, 25.5% or less, 24.5% or less, 23.5% or less, 21.5% or less, 20.5% or less, 19.5% or less, 18.5% or less, 17.5% or less, 16.6% or less, 15.5% or less, 14.5% or less, and 13.5% or less. From the viewpoint of avoiding an increase in the expansion and contraction of the glass due to an increase in the thermal expansion coefficient and avoiding the occurrence of cracks and breakages in the glass due to stress applied to the glass when the volume change of the glass is restricted by other components, the total content (Li O) is preferably 35.0% or less, and is more preferably 33.5% or less, 32.5% or less, 31.5% or less, 30.5% or less, 29.5% or less, 28.5% or less, 27.5% or less, 26.5% or less, 25.5% or less, 24.5% or less, 23.5% or less, 21.5% or less, 20.5% or less, 19.5% or less, 18.5% or less, 17.5% or less, 16.6% or less, 15.5% or less, 14.5% or less, and 13.5% or less. 2 O+Na 2 O+K 2 O) is less than the above value.

[0297] From the viewpoint of suppressing the deliquescent property of glass, Na 2 O and K 2 Total content of O (Na 2 O+K 2O) is preferably 30.0% or less, and is more preferably 29.0% or less, 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, 9.0% or less, 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.0% or less, 3.0% or less, 2.0% or less, 1.0% or less, and 0.5% or less in this order. By 2 O and K 2 Total content of O (Na 2 O+K 2 On the other hand, from the viewpoint of suppressing the solubility of the glass, suppressing the decrease of T600, and suppressing the raw material cost of the glass, the total content (Na 2 O+K 2 O) is set to 1.0% or more, and can also be set to 2.0% or more, 3.0% or more, 4.0% or more, 5.0% or more, 6.0% or more, 7.0% or more, 8.0% or more, 9.0% or more, 10.0% or more, 11.0% or more, 12.0% or more, 13.0% or more, 14.0% or more, or 15.0% or more.

[0298] When adjusting the thickness of the glass, CuO may be replaced with other components. In this case, Na 2 O.K 2 Total content of O, CaO, SrO and BaO (Na 2 O+K 2 CuO concentration can be adjusted without significantly changing the position of near-infrared absorption. 2 O+K 2 O+CaO+SrO+BaO) is preferably 0.5% or more, and more preferably 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, 7.0% or more. However, there is a tendency to reduce T400 due to excessive introduction, so the total content (Na 2 O+K 2The total content (Na2O3) of the glass is preferably 36.0% or less, and is more preferably 35.0% or less, 34.0% or less, 33.0% or less, 32.0% or less, 31.0% or less, 30.0% or less, 29.0% or less, 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, and 9.0% or less in this order. From the viewpoint of maximizing the near-infrared absorption characteristics of the glass, the total content (Na2O3) of the glass is preferably 36.0% or less, and is more preferably 35.0% or less, 34.0% or less, 33.0% or less, 32.0% or less, 31.0% or less, 30.0% or less, 29.0% or less, 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 1 2 O+K 2 O+CaO+SrO+BaO) can also be 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, or 4.0% or less.

[0299] Regarding weather resistance, one or both of the inhibition of deliquescence of glass and the inhibition of precipitation on the glass surface under high temperature and high humidity can be used as an index of weather resistance. This will be further described later. In order to further improve weather resistance, it is preferred to introduce Al 2 O 3 , then preferably import Y 2 O 3 ,La 2 O 3 and Gd 2 O 3 In addition, the weather resistance can be improved by introducing more BaO. From the perspective of improving weather resistance, more SrO and CaO need to be introduced. Therefore, "(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3+BaO / 3+(CaO+SrO) / 6)” (unit: mol %) is preferably 0% or more, more preferably more than 0%, preferably 0.5% or more, 1.0% or more, 2.0% or more, 3.0% or more, 4.0% or more, 5.0% or more, 6.0% or more, 7.0% or more, 8.0% or more. In addition, when paying attention to the weather resistance and mechanical strength of the glass, it is more preferably 9.0% or more, 10.0% or more, 11.0% or more, 12.0% or more, 13.0% or more, 14.0% or more, 15.0% or more, 16.0% or more, 17.0% or more, 18.0% or more, 19.0% or more. 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6)", "Al 2 O 3 "For Al 2 O 3 Content, "Y 2 O 3 ” is Y 2 O 3 Content, "La 2 O 3 "For La 2 O 3 Content, "Gd 2 O 3 "Gd 2 O 3 content, "BaO" is the BaO content, "CaO" is the CaO content, and "SrO" is the SrO content. That is, "(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6)” is Al 2 O 3 The value calculated by multiplying the content by 3 is Y 2 O 3 Content, La 2 O 3 Content, Gd 2 O 3The total of the values ​​calculated as 1 / 3 of the BaO content and 1 / 6 of the total of the CaO content and the SrO content are expressed by adding % (mol %) to the values ​​calculated in this way.

[0300] On the other hand, if the excessive increase "(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6)”, the solubility of the glass tends to deteriorate, and the position of near-infrared absorption tends to shift to the visible light side. Therefore, “(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 The value calculated by "(CaO + SrO) / 6)" is preferably 40.0% or less, and more preferably 37.0% or less, 35.0% or less, 33.0% or less, 32.0% or less, 30.0% or less, 28.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, and 21.0% or less.

[0301] For P 2 O 5 , Li 2 The total content of O and CuO is determined by “(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6)”, i.e., “(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6) / (P 2 O 5 +Li 2O + CuO)" can be 0.0 or more. It is expected that P as an essential component 2 O 5 , Li 2 O and CuO introduce a certain amount or more of selected from Al 2 O 3 , Y 2 O 3 ,La 2 O 3 , Gd 2 O 3 , BaO, CaO and SrO. Therefore, the above ratio is preferably 0.01 or more, and more preferably in the order of 0.02 or more, 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, and 0.09 or more. In the case of further improving weather resistance, the above ratio is further preferably set to 0.10 or more, and more preferably in the order of 0.11 or more, 0.12 or more, 0.13 or more, 0.14 or more, 0.15 or more, 0.16 or more, 0.17 or more, 0.18 or more, 0.19 or more, 0.20 or more, 0.21 or more, 0.22 or more, 0.23 or more, 0.24 or more, or 0.25 or more.

[0302] On the other hand, if the above ratio is increased excessively, the transmittance characteristics of the glass will decrease, and the tendency of the stability of the glass to decrease will also become stronger. Therefore, the above ratio is preferably below 0.36, and more preferably below 0.35, below 0.34, below 0.33, below 0.32, below 0.31, below 0.30, below 0.29, and below 0.28.

[0303] The ZnO content may be 0%, 0% or more, or more than 0%. ZnO is a component that can be appropriately added for reasons such as adjusting the thermal stability of the glass, but it tends to reduce the weather resistance of the glass. In addition, it is difficult to fully ensure the P content as an essential component. 2 O 5From the perspective of the amount of ZnO introduced, the upper limit of the content is preferably 20.0% or less, and is more preferably in the order of 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, 9.0% or less, 8.0% or less, 7.0% or less, 6.0% or less, and 5.0% or less. In the case where the introduction effect of other components is given priority, the content of ZnO may be 4.0% or less, 3.0% or less, 2.0% or less, and 1.0% or less. On the other hand, in the case of introducing ZnO to adjust the thermal stability of the glass and lower Tg and / or Tm, it is more preferably in the order of 0.4% or more, 0.6% or more, 0.8% or more, 1.0% or more, 1.2% or more, 1.4% or more, 1.6% or more, 1.8% or more, and 2.0% or more.

[0304] The glass is preferably basically composed of the above components, but may contain other components within a range that does not hinder the effects of the above components. In addition, the glass may contain inevitable impurities.

[0305] For example, in order to adjust the weather resistance and mechanical strength of the glass or to improve the thermal stability, Nb may be appropriately introduced in an amount exceeding 0%, 0.1% or 0.2%. 2 O 5 、ZrO 2 As components other than the above components, their contents are preferably 5.0% or less, more preferably 4.0% or less, 3.0% or less, 2.0% or less, 1.0% or less, 0.5% or less, and 0.3% or less. The contents of these components may be 0% respectively.

[0306] In order to adjust the weather resistance and mechanical strength of the glass or to improve the thermal stability without affecting the transmittance of the glass, more than 0%, 0.1% or 0.2% of TiO may be appropriately introduced. 2 , WO 3 、Bi 2 O 3 The content of the components other than the above components is preferably 4.0% or less, more preferably 3.0% or less, 2.0% or less, 1.0% or less, 0.5% or less, and 0.3% or less. The content of each of these components may be 0%.

[0307] Pb, As, Cd, Tl, Be, and Se are all toxic. Therefore, the glass preferably does not contain these elements as glass components.

[0308] U, Th, and Ra are all radioactive elements. Therefore, the glass preferably does not contain these elements as glass components.

[0309] V, Cr, Mn, Fe, Co, Ni, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, and Tm can increase the coloring of the glass and become a source of fluorescence. Therefore, in the above-mentioned glass, the total content of these elements based on the oxides is preferably set to 10 mass ppm or less, and it is more preferable not to contain these elements as glass components.

[0310] Among them, V 2 O 5 It is preferably not used because of its toxicity. That is, in one embodiment, glasses 1 to 6 are preferably glasses that do not contain V ions, and in the glass composition based on oxides (molar basis), V 2 O 5 The content is preferably 1.0% or less, more preferably 0.3% or less, 0.1% or less, and 0.01% or less in this order, and it is further preferred that V is not contained. 2 O 5 .

[0311] As an example, as V 2 O 5 With the necessary ingredients Li 2 Ratio of O, V 2 O 5 Content relative to Li 2 O content ratio (V 2 O 5 / Li 2 O) is preferably 0.0080 or less, more preferably 0.0048 or less, 0.0028 or less, 0.0018 or less, and 0.0014 or less in this order.

[0312] CoO reduces the transmittance of the glass in the visible region and is toxic, so it is preferably not used. That is, in one embodiment, glasses 1 to 6 are preferably glasses that do not contain Co ions, and preferably do not contain CoO in the glass composition based on oxides.

[0313] The raw materials for introducing Ge and Ta into glass are expensive, so it is preferred that the glass does not contain these elements as glass components.

[0314] Sb(Sb 2 O 3 )、Sn(SnO 2 )、Ce(CeO 2 ) and SO 3 It is an element that can be added optionally to function as a clarifier. 2 O 3) is a clarifier with remarkable clarification effect.

[0315] Sn(SnO 2 )、Ce(CeO 2 ) and Sb(Sb 2 O 3 ) have a smaller clarification effect than Sb. If these clarifiers are added in large amounts, there is a tendency to cause the coloring of the glass to become stronger. Therefore, when adding clarifiers, it is preferred to add Sb (Sb) while considering the effect of coloring caused by the addition. 2 O 3 ).

[0316] The contents of the components that can function as clarifiers described below are values ​​in the glass composition based on oxides.

[0317] Sb 2 O 3 In other words, except for Sb 2 O 3 SnO 2 、CeO 2 and SO 3 When the total content of all glass components other than Sb in terms of oxides is 100.0 mass %, 2 O 3 The content is preferably less than 2.0% by mass, and more preferably in the order of 1.5% by mass or less, 1.2% by mass or less, 1.0% by mass or less, 0.9% by mass or less, 0.8% by mass or less, 0.7% by mass or less, 0.6% by mass or less, 0.5% by mass or less, 0.4% by mass or less, 0.3% by mass or less, 0.2% by mass or less, and less than 0.1% by mass. Sb 2 O 3 The content of Sb may be 0% by mass. However, from the viewpoint of promoting the oxidation of glass and improving the transmittance in the visible region, Sb may be reduced to 0% by mass. 2 O 3 The content may be 0.01% by mass or more, and may be 0.02% by mass or more, 0.03% by mass or more, 0.04% by mass or more, 0.05% by mass or more, 0.06% by mass or more, or 0.08% by mass or more.

[0318] SnO 2 The content is also expressed as an external ratio. 2 , Sb 2 O 3 、CeO 2 and SO 3 When the total content of all glass components other than SnO in terms of oxides is 100.0 mass %, 2The content of SnO is preferably less than 2.0 mass%, more preferably less than 1.0 mass%, 0.9 mass% or less, and more preferably in the order of 0.8 mass% or less, 0.7 mass% or less, 0.6 mass% or less, 0.5 mass% or less, 0.4 mass% or less, 0.3 mass% or less, 0.2 mass% or less, and 0.1 mass%. SnO 2 The content of SnO may be 0 mass%. 2 When the content is within the above range, the clarity of the glass can be improved.

[0319] CeO 2 The content is also expressed as an external ratio. 2 , Sb 2 O 3 SnO 2 and SO 3 When the total content of all glass components other than CeO in terms of oxides is 100.0 mass %, 2 The content is preferably less than 2.0 mass%, more preferably less than 1.0 mass%, 0.9 mass% or less, and more preferably in the order of 0.8 mass% or less, 0.7 mass% or less, 0.6 mass% or less, 0.5 mass% or less, 0.4 mass% or less, 0.3 mass% or less, 0.2 mass% or less, and less than 0.1 mass%. CeO 2 The content may be 0 mass %. 2 When the content is within the above range, the clarity of the glass can be improved.

[0320] SO 3 The content is also expressed as an external ratio. 3 , Sb 2 O 3 SnO 2 、CeO 2 When the total content of all glass components other than SO in terms of oxides is 100.0 mass %, 3 The content is preferably less than 2.0 mass %, more preferably less than 1.0 mass %, further preferably less than 0.5 mass %, and further preferably less than 0.1 mass %. 3 The content may be 0 mass %. 3 When the content of is within the above range, the clarity of the glass can be improved.

[0321] <Glass Properties>

[0322] (Transmittance characteristics)

[0323] The above-mentioned glass is suitable as glass for near infrared cut filter. In the present invention and this specification, "transmittance" means external transmittance including reflection loss unless otherwise specified.

[0324] Regarding the near infrared blocking ability, the wavelength at which the transmittance reaches 50% at a wavelength of 550nm or more, i.e. the half value λ T 50 can be used as an indicator, the transmittance T1200 at a wavelength of 1200nm can be used as an indicator, the average value of the transmittance in the range of wavelengths 1100nm to 800nm ​​(recorded as "Ave. T1100-800") can be used as an indicator, and the transmittance T750 at a wavelength of 750nm can be used as an indicator.

[0325] The glass can also show high transmittance in the visible region. Regarding the transmittance in the visible region, the transmittance T400 at a wavelength of 400 nm can be used as an indicator, and the transmittance T600 at a wavelength of 600 nm can be used as an indicator.

[0326] The transmittance characteristics of glass are values ​​obtained by the following method.

[0327] The glass sample is processed into parallel and optically polished planes, and the external transmittance at a wavelength of 200 to 1200 nm is measured. The external transmittance also includes the reflection loss of light on the test surface.

[0328] The intensity of light incident vertically on one plane after optical polishing is defined as intensity A, and the intensity of light emitted from the other plane is defined as intensity B. The spectral transmittance B / A including reflection loss is calculated. The wavelength at which the spectral transmittance reaches 50% at a wavelength of 550nm or more is defined as the half-value λ. T 50. The spectral transmittance at a wavelength of 400 nm is set to T400, the spectral transmittance at a wavelength of 600 nm is set to T600, and the spectral transmittance at a wavelength of 1200 nm is set to T1200. The average value of the spectral transmittance in the range of wavelengths from 1100 nm to 800 nm is set to Ave.T1100-800, and the spectral transmittance at a wavelength of 750 nm is set to T750.

[0329] In addition, when the glass to be measured is not glass of the converted thickness, the thickness of the glass can be set to d, the transmittance at each wavelength λ can be converted by the following formula A, and various conversion values ​​can be calculated based on the converted transmittance characteristics.

[0330] Formula A: T(λ) = (1 - R(λ)) 2 ×exp(log e ((T 0(λ) / 100) / (1-R(λ)) 2 )×d / d 0 )×100

[0331] In formula A, T(λ): converted transmittance (%) at wavelength λ, T 0 (λ): measured transmittance at wavelength λ (%), d: converted thickness (mm), d 0 : Glass thickness (mm), R(λ)=((n(λ)-1) / (n(λ)+1)) 2 : The reflectivity at wavelength λ, n(λ): refractive index at wavelength λ. Here, calculations were performed assuming that n(λ)=1.51680 and R(λ)=0.042165 are constants.

[0332] A high value of T600, which is the transmittance in the red region, and a low value of T1200, which is the transmittance in the near-infrared region, can mean that both the transmittance in the visible region and the near-infrared blocking ability are improved. In addition, a high value of T400, which is the transmittance in the purple region, can also mean that the transmittance in the visible region is improved.

[0333] From the above viewpoints, the preferred ranges of T400, T600 and T1200 are as follows.

[0334] Regarding T400, it is preferably 70% or more, and more preferably in the order of 71% or more, 72% or more, 73% or more, 74% or more, 75% or more, 76% or more, 77% or more, 78% or more, 79% or more, and 80% or more. T400 may be, for example, 98% or less, 97% or less, or 96% or less, but a higher T400 may mean better visible light transmittance, and therefore, it is also preferably higher than the values ​​exemplified above.

[0335] Regarding T600, it is preferably 50% or more, and more preferably 55% or more, 56% or more, 57% or more, 58% or more, 59% or more, 60% or more, 61% or more, 62% or more, 63% or more, 64% or more, 65% or more, 66% or more, 67% or more, 68% or more, 69% or more, 70% or more, 71% or more, 72% or more, 73% or more, 74% or more, and 75% or more. T600 may be, for example, 90% or less, 85% or less, or 80% or less, but a higher T600 may also mean better visible light transmittance, and therefore, it is also preferably higher than the values ​​exemplified above.

[0336] Regarding T1200, it is preferably 30% or less, and more preferably 29% or less, 28% or less, 27% or less, 26% or less, 25% or less, 24% or less, 23% or less, 22% or less, 21% or less, 20% or less, 19% or less, 18% or less, 17% or less, 16% or less, 15% or less, 14% or less, 13% or less, 12% or less, 11% or less, 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, 2% or less, and 1% or less. For the purpose of taking visible light transmittance into consideration, T1200 may be, for example, 1% or more, 3% or more, 5% or more, or 7% or more, but a lower T1200 may mean a better near-infrared shielding ability, and therefore, it is also preferably lower than the values ​​exemplified above.

[0337] In one embodiment, T1200 may be β1% or less.

[0338] β1 is calculated by the following formula B1, where R is the O / P ratio.

[0339] (Formula B1)

[0340] β1=64×R-170

[0341] In one embodiment, T1200 may be equal to or less than the numerical values ​​represented by β2, β3, β4, β5, and β6 represented by the following formulas B2 to B6 (unit: %), where R represents the O / P ratio.

[0342] Formula B2: β2 = 64 × R-175

[0343] Formula B3: β3=64×R-180

[0344] Formula B4: β4 = 80 × R - 220

[0345] Formula B5: β5 = 80 × R-224

[0346] Formula B6: β6 = 80 × R - 228

[0347] The wavelength at which the spectral transmittance reaches 50% at a wavelength of 550nm or above, i.e., the half-value λ T 50 is preferably 600 nm or more, and more preferably 610 nm or more, 613 nm or more, 615 nm or more, 617 nm or more, 620 nm or more, 623 nm or more, 625 nm or more, and 628 nm or more in this order. T50 is preferably 650nm or less, and more preferably 647nm or less, 645nm or less, 643nm or less, 641nm or less, 640nm or less, 639nm or less, and 638nm or less. From the viewpoint of achieving both thinning of the glass and improvement of the near-infrared shielding ability, it is preferred that the wavelength at which the spectral transmittance reaches 50% at a wavelength of 550nm or more, i.e., the half value λ T 50. The glass thickness given below is preferably 0.25 mm or less.

[0348] In addition, since the above-mentioned glass has excellent absorption characteristics in the near-infrared region, "Ave.T1100-800" can be suppressed to 15% or less. "Ave.T1100-800" is preferably 14% or less, and more preferably 13% or less, 12% or less, 11% or less, 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, 2% or less, 1.3% or less, 1.0% or less, 0.3% or less, 0.1% or less, 0.03% or less, and 0.01% or less in this order.

[0349] In addition, since the glass has excellent absorption characteristics in the near-infrared region, T750 can be suppressed to 25% or less. T750 is preferably 24% or less, and more preferably in the order of 23% or less, 22% or less, 21% or less, 20% or less, 19% or less, 18% or less, 17% or less, 16% or less, 15% or less, 14% or less, 13% or less, 12% or less, 11% or less, 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, 2% or less, 1.3% or less, 1.0% or less, 0.3% or less, 0.1% or less, 0.03% or less, and 0.01% or less.

[0350] As described in detail later, the glass can be used as glass for a near-infrared cut filter having a thickness of 0.25 mm or less in one embodiment.

[0351] Regarding the above-mentioned glass, as the preferred transmittance characteristics for the glass for near-infrared cutoff filter thinned to a thickness of 0.25 mm or less, the following (a) to (h) can be cited. The above-mentioned glass preferably satisfies one or more of the following (a) to (h), and may also satisfy two or more. By adjusting the glass composition as described above, a glass having a preferred transmittance characteristic can be obtained.

[0352] (a) The wavelength λ at which the external transmittance including reflection loss reaches 50% at a wavelength of 550 nm or more TThe thickness of the glass reaching 50 to 633 nm is 0.25 mm or less. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 30% or less.

[0353] Regarding (a) above, the wavelength λ at which the external transmittance including reflection loss reaches 50% at a wavelength of 550 nm or more is T The thickness of the glass having a wavelength of 50 to 633 nm is 0.25 mm or less, and more preferably is within the thickness range described later for the thickness of the near infrared cut filter. This also applies to the following (b), (e) and (f).

[0354] (b) The thickness of the glass having an external transmittance of 50% including reflection loss at a wavelength of 550 nm or more and a wavelength of 633 nm is 0.25 mm or less. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is β1% or less. β1 is a value calculated by the following formula B1. In formula B1, R is the O / P ratio of the above glass.

[0355] (Formula B1)

[0356] β1=64×R-170

[0357] As described above, T1200 may be β2% or less, β3% or less, β4% or less, β5% or less, or β6% or less.

[0358] (c) As the transmittance characteristic converted to a thickness of 0.11 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% T 50 In the range of 600nm to 650nm, the external transmittance T1200 including reflection loss at a wavelength of 1200nm is 30% or less, and the external transmittance T400 including reflection loss at a wavelength of 400nm is 70% or more.

[0359] (d) As the transmittance characteristic converted to a thickness of 0.21 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% T 50 In the range of 600nm to 650nm, the external transmittance T1200 including reflection loss at a wavelength of 1200nm is 25% or less, and the external transmittance T400 including reflection loss at a wavelength of 400nm is 70% or more.

[0360] (e) The thickness of the glass at a wavelength of 645 nm, at which the external transmittance including reflection loss at a wavelength of 550 nm or more reaches 50%, is 0.25 mm or less. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 30% or less.

[0361] (f) The wavelength λ at which the external transmittance including reflection loss reaches 50% at a wavelength of 550 nm or more T The thickness of the glass reaching 50 to 645nm is less than 0.25mm. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600nm is more than 50%, and the external transmittance T1200 including reflection loss at a wavelength of 1200nm is less than β1%, where β1 is the value calculated by the formula B1 recorded above.

[0362] (g) As the transmittance characteristic converted to a thickness of 0.23 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% T 50 In the range of 600nm to 650nm, the external transmittance T1200 including reflection loss at a wavelength of 1200nm is 18% or less, and the external transmittance T400 including reflection loss at a wavelength of 400nm is 70% or more.

[0363] (h) As the transmittance characteristic converted to a thickness of 0.25 mm, the wavelength λ at which the external transmittance including reflection loss reaches 50% T 50 In the range of 600nm to 650nm, the external transmittance T1200 including reflection loss at a wavelength of 1200nm is less than 16%, and the external transmittance T400 including reflection loss at a wavelength of 400nm is more than 70%.

[0364] (Weather resistance)

[0365] The glass can show excellent weather resistance by having the composition described above. Regarding weather resistance, for example, the evaluation result of weather resistance evaluated by visual observation by the method described in the embodiments described later can be used as an indicator, and the evaluation result is preferably any result from S to D, more preferably any result from S to C, further preferably any result from S to B, further preferably S or A, and further preferably S.

[0366] In addition, the haze value measured by a haze meter may be used as an index for weather resistance. Glass having a haze value of 15% or less is cited as an example of glass having better weather resistance.

[0367] With regard to weather resistance, it is more preferred that the evaluation result by visual observation described above is S or A (preferably S), and the haze value measured by a haze meter is 15% or less.

[0368] (Glass transition temperature Tg, temperature Tm at which the endothermic reaction due to melting converges)

[0369] The glass transition temperature of the glass is not particularly limited. From the viewpoint of improving the transmittance of the glass in the short wavelength range by improving the meltability of the glass and reducing the burden on the annealing furnace and the molding device, Tg is preferably 450°C or less, and more preferably in the order of 440°C or less, 430°C or less, 420°C or less, 410°C or less, and 400°C or less. From the viewpoint of improving the chemical durability and / or heat resistance of the glass, Tg is preferably 250°C or more, and more preferably in the order of 260°C or more, 270°C or more, 280°C or more, 290°C or more, and 300°C or more.

[0370] The Tg value of glass can be obtained by Li 2 O、Na 2 O.K 2 O content, total content, ZnO content, MgO content, Al 2 O 3 It can be controlled by adjusting the content and the total content.

[0371] The temperature Tm at which the endothermic reaction based on melting of the above-mentioned glass converges is not particularly limited. The lower the Tm, the better the solubility. There is a tendency that devitrification does not occur in the glass even if molding is performed at a higher viscosity. In addition, there is a tendency that the better the solubility, the more the transmittance of the glass in the visible region of the short wavelength range can be improved. From these viewpoints, Tm is preferably below 890°C, and further preferably in the order of below 880°C, below 870°C, below 860°C, below 850°C, below 840°C, below 830°C, below 820°C, below 810°C, below 800°C, below 790°C, below 780°C, below 770°C, below 760°C, below 750°C, below 740°C, below 730°C, below 720°C, below 710°C, below 700°C, below 690°C, below 680°C, below 670°C, below 660°C, and below 650°C. The lower limit of Tm is not particularly limited. However, if Tm is too low, the weather resistance of the glass tends to decrease. Therefore, Tm may be 500°C or higher, 550°C or higher, 580°C or higher, 600°C or higher, 620°C or higher, or 640°C or higher.

[0372] The Tm value of glass can be obtained by Li 2 O、Na 2O.K 2 O content, total content, ZnO content, MgO content, Al 2 O 3 It can be controlled by adjusting the content and the total content.

[0373] (proportion)

[0374] Since it is related to the lightness of the element or device provided with the filter, it is preferable that the near infrared cut filter is light. In view of this point, the specific gravity of the above-mentioned glass is preferably 3.40 or less, and more preferably in the order of 3.35 or less, 3.30 or less, 3.25 or less, 3.20 or less, 3.15 or less, 3.10 or less, 3.05 or less, 3.00 or less, 2.95 or less, 2.90 or less, 2.85 or less, 2.80 or less, 2.75 or less, 2.70 or less, 2.65 or less, and 2.60 or less.

[0375] The specific gravity may be, for example, 2.0 or more or 2.4 or more. From the above viewpoint, the specific gravity is preferably lower, and therefore, it is also preferably lower than the values ​​exemplified here.

[0376] (Molar volume)

[0377] There is no particular limitation on the molar volume M / D of the glass, but from the viewpoint of increasing the near-infrared absorption capability by increasing the amount of CuO per unit volume, a smaller molar volume of the glass is preferred. 2 O 5 ,La 2 O 3 , Y 2 O 3 , Gd 2 O 3 , BaO, K 2 O is replaced by Li 2 O, the molar volume can be reduced. If Al 2 O 3 , CuO, Na 2 O is replaced by Li 2 O, the molar volume can be slightly reduced. On the other hand, even if CaO, ZnO, and SrO are replaced by Li 2 O, the molar volume will not change significantly. If MgO is replaced by Li 2O, there is a tendency for the molar volume to increase. Considering these tendencies, the molar volume of the glass can be adjusted by adjusting the glass composition. The molar volume is preferably 45cc / mol or less, and more preferably in the order of 43cc / mol or less, 42cc / mol or less, 41cc / mol or less, 40cc / mol or less, 39.5cc / mol or less, 39.0cc / mol or less, 38.5cc / mol or less, 38.0cc / mol or less, and 37.5cc / mol or less.

[0378] On the other hand, from the perspective of maintaining the weather resistance of the glass, the molar volume can also be increased. From this point of view, the molar volume of the above-mentioned glass can be greater than 34.0cc / mole, or greater than 35.0cc / mole, greater than 36.0cc / mole, greater than 36.5cc / mole, greater than 37.0cc / mole, greater than 37.5cc / mole, greater than 38.0cc / mole, greater than 38.5cc / mole, greater than 39.0cc / mole, or greater than 39.5cc / mole.

[0379] <Glass Manufacturing Method>

[0380] The above-mentioned glass can be obtained by mixing, melting and molding various glass raw materials. Regarding the production method, reference can also be made to the description described below.

[0381] The near-infrared absorbing glass is suitable as glass for near-infrared cut-off filters. In addition, the near-infrared absorbing glass can also be applied to optical elements (lenses, etc.) other than near-infrared cut-off filters, and can also be applied to various glass products and can be variously deformed.

[0382] [Near infrared cut filter]

[0383] One embodiment of the present invention relates to a near infrared cut filter (hereinafter, also simply referred to as a “filter”) made of the above-mentioned near infrared absorbing glass.

[0384] The glass constituting the above-mentioned optical filter is as described above.

[0385] A specific example of the method for producing the optical filter will be described below, but the following method is for illustrative purposes only and does not limit the present invention.

[0386] For molten glass, glass raw materials such as phosphates, oxides, carbonates, nitrates, sulfates, and fluorides are appropriately used, and the raw materials are weighed and mixed in a manner to achieve the desired composition, and then melted in a melting container such as a platinum crucible, for example, at 800°C to 1100°C. At this time, in order to suppress the volatilization of volatile components, a lid of platinum or the like can also be used. In addition, the melting can be carried out in the atmosphere, and in order to suppress the change in the valence of Cu, an oxygen atmosphere can also be formed, or oxygen bubbling can be carried out in the molten glass. The glass in the molten state becomes a homogenized molten glass with fewer bubbles (preferably without bubbles) by stirring and clarifying. It should be noted that after clarifying the glass at 900°C to 1100°C, in order to promote the oxidation of the glass, the glass can also be obtained after the glass is cooled to 800°C to 1000°C. However, it is not expected that the melting temperature and the clarifying temperature are lower than the liquidus temperature of the glass for a long time.

[0387] After stirring and clarifying the molten glass, the glass is made to flow out, and after slowly cooling, it is formed into a desired shape. When making the glass flow out, if it is cooled to a temperature near the liquidus temperature and the viscosity of the glass is increased, convection of the flowing glass is less likely to occur, and wave lines are less likely to occur, so it is preferred. As the slow cooling rate, a rate between -50°C / hr and -1°C / hr can be selected, and -30°C / hr and -10°C / hr can also be selected.

[0388] As a glass forming method, known methods such as casting, pipe outflow, rolling, pressing, etc. can be used. The formed glass is transferred to an annealing furnace preheated to near the glass transition temperature and slowly cooled to room temperature. In this way, a near infrared cutoff filter can be manufactured.

[0389] An example of a molding method is described below. A mold consisting of a flat and horizontal bottom surface, a pair of side walls sandwiching the bottom surface and facing each other in parallel, and a weir plate located between the pair of side walls and closing one side opening is prepared. Homogenized molten glass is injected into the mold at a constant outflow rate from a platinum alloy pipe. The injected molten glass is spread out in the mold and molded into a glass plate that is limited to a certain width by a pair of side walls. The molded glass plate is continuously pulled out from the opening of the mold. Here, by appropriately setting the molding conditions such as the shape, size, and outflow rate of the molten glass of the mold, it is possible to mold a large and thick glass block. The molded glass mold is transferred to an annealing furnace preheated to near the glass transition temperature and slowly cooled to room temperature. The glass molded body after the strain is removed by slow cooling is subjected to mechanical processing such as slicing, grinding, and polishing. In this way, a near-infrared cutoff filter in a shape corresponding to the purpose, such as a plate shape or a lens shape, can be obtained. Alternatively, a method may be adopted in which a preform made of the above glass is formed, heated, softened, and then press-formed (particularly, a precision press-forming method in which the final product is press-formed without subjecting the optical functional surface to mechanical processing such as grinding and polishing). An optical multilayer film may also be formed on the surface of the optical filter as required.

[0390] The near infrared cut filter can have both excellent near infrared blocking capability and high transmittance in the visible region. With such a near infrared cut filter, the color sensitivity correction of the semiconductor imaging element can be performed well.

[0391] In addition, the near infrared cut filter can be applied to a camera device by combining it with a semiconductor image sensor. The semiconductor image sensor has a semiconductor imaging element such as a CCD or CMOS installed in the component, and the light receiving part is covered by a light-transmitting member. The light-transmitting member can be used as a near infrared cut filter at the same time, or the light-transmitting member and the near infrared cut filter can be different members.

[0392] The imaging device may include an optical element such as a lens or a prism on the light receiving surface of the semiconductor image sensor for forming an image of the object to be imaged.

[0393] Furthermore, by using the above-mentioned near infrared cut filter, it is possible to provide an imaging device that can perform color sensitivity correction well and obtain an image with excellent image quality.

[0394] The above-mentioned near-infrared cut-off filter can be a near-infrared cut-off filter with a thickness of less than 0.25mm in one embodiment. In recent years, due to the emergence of smart phones, the tendency to reduce the thickness of the camera of the imaging element is significant, and with this, the near-infrared cut-off filter is also expected to exert performance with a thinner thickness. As such a near-infrared cut-off filter, the above-mentioned near-infrared cut-off filter is also preferred. The thickness of the above-mentioned near-infrared cut-off filter can be less than 0.24mm, less than 0.23mm, less than 0.22mm, less than 0.21mm, less than 0.20mm, less than 0.19mm, less than 0.18mm, less than 0.17mm, less than 0.16mm, less than 0.15mm, less than 0.14mm, less than 0.13mm or less than 0.12mm. The thickness of the above-mentioned near-infrared cut-off filter can be, for example, 0.21mm or 0.11mm. In addition, the thickness of the near infrared cut filter can be, for example, 0.50 mm or more, but is not limited thereto. In the present invention and this specification, "thickness" refers to the thickness of the sample in the area where the transmittance is measured, and can be measured by a thickness gauge, a micrometer, etc. For example, the thickness of the approximate center of the position where the transmitted light passes can be measured, or the thickness of multiple points can be measured within the light spot of the transmitted light and the average value can be taken.

[0395] Regarding the transmittance characteristics of the near-infrared cut filter, the above description regarding glasses 1 to 6 can be referred to. Furthermore, regarding the physical properties of the near-infrared cut filter, the above description regarding glasses 1 to 6 can also be referred to.

[0396] Example

[0397] Hereinafter, the present invention will be described in more detail with reference to the examples, but the present invention is not limited to the examples.

[0398] [Examples 1 to 66, Comparative Examples X, A to D]

[0399] As glass raw materials, phosphates, fluorides, carbonates, nitrates, oxides, etc. are weighed and mixed in such a way that 150 g to 300 g of glass of the composition shown in Table 1 can be obtained, and then placed in a platinum crucible or a quartz crucible, melted at 800°C to 1000°C for 80 minutes to 100 minutes, stirred to degas and homogenize, and then poured into a preheated mold and formed into a given shape. The obtained glass molded body is transferred to an annealing furnace heated to near the glass transition temperature and slowly cooled to room temperature. A test piece is cut out from the obtained glass, and after mirror polishing on both sides to a thickness of about 0.2 mm, various evaluations are performed by the following methods.

[0400] [Evaluation method]

[0401] <Transmittance characteristics>

[0402] The transmittance of each test piece at a wavelength of 200 to 1200 nm was measured using a spectrophotometer. Based on the measurement results, the transmittance was converted into values ​​of half-value 645 nm, half-value 633 nm, thickness 0.11 mm, thickness 0.21 mm, thickness 0.23 mm, and thickness 0.25 mm, and the half-value (unit: nm), T400, T600, T1200, Ave. T1100-800 (unit: %) were obtained.

[0403] <Glass transition temperature Tg, temperature Tm at which the endothermic reaction due to melting converges>

[0404] The glass transition temperature Tg and the temperature Tm at which the endothermic reaction due to melting converged were measured using a differential scanning calorimeter (DSC8270) manufactured by Rigaku Corporation at a heating rate of 10°C / min. The measurement temperature range was set to a range of room temperature to 1050°C.

[0405] <Specific Gravity>

[0406] The specific gravity was measured by the Archimedean method.

[0407] <Molar volume>

[0408] The molar volume was calculated from the measured specific gravity using the method described above.

[0409] <Evaluation classification of weather resistance>

[0410] Each test piece was kept in a constant temperature and humidity chamber at a temperature of 85° C. and a relative humidity of 85% for 3.5 hours, and then visually evaluated for appearance under a fluorescent lamp. Based on the evaluation results, weather resistance was evaluated according to the following criteria.

[0411] S: Fogging and / or precipitates observed on the surface are extremely slight.

[0412] A: Fogging and / or precipitates observed on the surface are slight.

[0413] B: Slightly strong fogging and / or generation of precipitates were observed on the surface.

[0414] C: Wetting of the surface showing deliquescence was observed but was slight, and / or thick precipitates were generated.

[0415] D: Deliquescence to such an extent that the plate thickness is significantly reduced and / or generation of precipitates covering the plain glass are not observed.

[0416] E: Deliquescence to such an extent that the plate thickness is significantly reduced is observed, and / or precipitates are generated to such an extent that plain glass is not observed.

[0417]

[0418]

[0419]

[0420]

[0421]

[0422]

[0423]

[0424]

[0425]

[0426]

[0427]

[0428]

[0429]

[0430]

[0431]

[0432]

[0433]

[0434]

[0435]

[0436]

[0437]

[0438] From the results shown in the above table, it can be confirmed that the glasses of Examples 1 to 66 have high transmittance in the visible region (purple region to red region) even when thinned, are excellent in near-infrared shielding ability, and suppress deterioration in weather resistance.

[0439] As for weather resistance, it was confirmed by comparing Examples 1 to 58 with Example 59 that the 2 O 3 +Y2 O 3 +La 2 O 3 +Gd 2 O 3 In Example 59, the calculated value of "(CaO + SrO) / 6)" is 0, and the weather resistance of Examples 1 to 58 with larger values ​​is better.

[0440] Regarding the comparison between Example 59 and Example 60, "(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6)” is 0, and “(Na 2 O+K 2 O+ZnO) / Li 2 Example 60, in which the value of O" exceeds 1.4 and is larger than that of Example 59, has a greater degree of deliquescence than Example 59 and is slightly inferior in weather resistance.

[0441] Comparative Example X is "(3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 +BaO / 3+(CaO+SrO) / 6)” exceeds 0, but “(Na 2 O+K 2 O+ZnO) / Li 2 The value of O" is large, exceeding 11, and the weather resistance is low.

[0442] Comparative Examples A, B, and C are composed only of P 2 O 5 , Li 2 Glass made of these three components, O and CuO, has very low weather resistance.

[0443] In Comparative Example D, the O / P ratio exceeded 3.2, and the desired transmittance characteristics were not obtained.

[0444] In the examples described above in which the evaluation based on visual observation for weather resistance was classified as S or A, haze values ​​were also obtained for Examples 25, 33, 56, and 61 to 66 using a haze meter. The obtained haze values ​​are shown in Table 8.

[0445] [Table 8]

[0446]

[0447] As shown in Table 8, compared with Example 25 and Example 33 which were rated A in the evaluation category of weather resistance evaluation based on visual observation, Examples 56 and 61 to 66 which were rated S in the evaluation category of weather resistance evaluation based on visual observation had lower haze values ​​of 15% or less.

[0448] Based on the above results, it can be confirmed that in order to achieve both an improvement in transmittance in the visible region and an improvement in near infrared shielding ability while further reducing the haze value to 15% or less, it is preferred that the O / P ratio be in the range of 3.00 to 3.15 and that the ratio of (3×Al 2 O 3 +Y 2 O 3 +La 2 O 3 +Gd 2 O 3 The value calculated by "(CaO + SrO) / 6)" (unit: mol %) is in the range of 10.0% to 40.0%.

[0449] Finally, summarize the above methods.

[0450] According to one embodiment, glasses 1 to 6 described in detail above are provided.

[0451] In one embodiment, in glasses 1 to 6, Al 2 O 3 The content may be less than 2.0 mol %.

[0452] In one embodiment, in glasses 1 to 6, Al 2 O 3 ,La 2 O 3 , Y 2 O 3 and Gd 2 O 3 Total content (Al 2 O 3 +La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) may be 0.1 mol % or more.

[0453] In one embodiment, glasses 1 to 6 may have the following transmittance characteristics.

[0454] Half value λ T50 The thickness of the glass reaching 633nm is 0.25mm or less, and the above half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at wavelengths above 550nm.

[0455] At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 30% or less.

[0456] Half value λ T 50 The thickness of the glass reaching 633nm is 0.25mm or less, and the above half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at wavelengths above 550nm.

[0457] At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is β1% or less.

[0458] β1 is a value calculated by the following formula B1,

[0459] (Formula B1)

[0460] β1=64×R-170

[0461] In the above formula B1, R is the above ratio (O ion / P ion).

[0462] As the transmittance characteristic converted to a thickness of 0.11 mm, the half value λ T 50In the range of 600nm~650nm, the above half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50%, the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 30% or less, and the external transmittance T400 including reflection loss at a wavelength of 400 nm is 70% or more.

[0463] As the transmittance characteristic converted to a thickness of 0.21 mm, the half value λ T 50In the range of 600nm~650nm, the above half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50%, the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 25% or less, and the external transmittance T400 including reflection loss at a wavelength of 400 nm is 70% or more.

[0464] Half value λT 50 The thickness of the glass reaching 645nm is less than 0.25mm, and the above half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at a wavelength of 550nm or more. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600nm is more than 50%, and the external transmittance T1200 including reflection loss at a wavelength of 1200nm is less than 30%.

[0465] Half value λ T 50 The thickness of the glass reaching 645nm is less than 0.25mm, and the above half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at a wavelength of 550nm or more. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200nm is β1% or less.

[0466] The above β1 is a value calculated by the following formula B1,

[0467] (Formula B1)

[0468] β1=64×R-170

[0469] In the above formula B1, R is the above ratio (O ion / P ion).

[0470] According to one embodiment, there is provided a near infrared cut filter made of the near infrared absorbing glass.

[0471] It should be understood that the embodiments disclosed this time are all exemplary and not restrictive. The scope of the present invention is defined by the claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0472] For example, by adjusting the composition of the glass composition exemplified above as described in the specification, the near infrared absorbing glass according to one embodiment of the present invention can be obtained.

[0473] Furthermore, it is of course possible to arbitrarily combine two or more of the features described as examples or as preferred ranges in the specification.

Claims

1. A near infrared absorbing glass comprising four or more main cations, wherein the main cations are selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions and Y ions, Contains P ions, Li ions and Cu ions as essential cations, contains at least O ions as anions, The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more. In the oxide-based glass composition, On a molar basis, The total content of the oxides of the main cations is 90.0% or more, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%, Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less, B 2 O 3 With SiO 2 Total content (B 2 O 3 +SiO 2 ) is less than 3.0%, CuO content is α 1 %above, α 1 is the value calculated by the following formula 1, Formula 1: a 1 =70400×exp(-2.855×R) In the formula 1, R is the ratio (O ions / P ions).

2. A near infrared absorbing glass comprising four or more main cations, wherein the main cations are selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions and Y ions, Contains P ions, Li ions and Cu ions as essential cations, and contains at least O ions as anions, The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more. In the oxide-based glass composition, On a molar basis, The total content of the oxides of the main cations is 90.0% or more, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%, Na 2 O content, K 2 The total of O content and 1 / 2 of ZnO content relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less, B 2 O 3 With SiO 2 Total content (B 2 O 3 +SiO 2 ) is less than 3.0%, The near-infrared absorbing glass satisfies the following formula 2: Formula 2: C-3200×exp(-2.278×R)≥0 In the formula 2, C is the average CuO content per molar volume of glass (unit: mmol / cc), R is the ratio (O ions / P ions).

3. A near infrared absorbing glass comprising four or more main cations, wherein the main cations are selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions, Contains P ions, Li ions and Cu ions as essential cations, and contains at least O ions as anions, The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more. In the oxide-based glass composition, On a molar basis, The total content of the oxides of the main cations is 90.0% or more, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%, Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less, A calculated by the following formula 3 1 More than 2500, Formula 3: A 1 ={O(P)-O(others)}×Cu In the formula 3, O(P) represents the amount of oxygen in the oxide that constitutes P ions in the oxide-based glass composition. O(others) represents the amount of oxygen obtained by removing O(P) from the amount of oxygen in the oxide constituting the main cation in the oxide-based glass composition. Cu represents the CuO content on a molar basis in the glass composition on an oxide basis.

4. A near-infrared absorbing glass comprising four or more main cations, wherein the main cations are selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions, Contains P ions, Li ions and Cu ions as essential cations, and contains at least O ions as anions, The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more. In the oxide-based glass composition, On a molar basis, The total content of the oxides of the main cations is 90.0% or more, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%, Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less, A calculated by the following formula 4 2 More than 700, Formula 4: A 2 ={O(P)-O(others)}×C In the formula 4, C is the average CuO content per molar volume of glass (unit: mmol / cc), O(P) represents the amount of oxygen in the oxide that constitutes P ions in the oxide-based glass composition. O(others) represents the amount of oxygen obtained by removing O(P) from the amount of oxygen in the oxide constituting the main cation in the oxide-based glass composition.

5. A near infrared absorbing glass comprising four or more main cations, wherein the main cations are selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions and Y ions, Contains P ions, Li ions and Cu ions as essential cations, and contains at least O ions as anions, The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more. In the oxide-based glass composition, On a molar basis, The total content of the oxides of the main cations is 90.0% or more, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%, Na 2 O content, K 2 The total content of O and ZnO relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less, CuO content is α 2 %above, α 2 is the value calculated by the following formula 5, Formula 5: a 2 =76522×exp(-2.855×R) In the formula 5, R is the ratio (O ions / P ions).

6. A near-infrared absorbing glass comprising four or more main cations, wherein the main cations are selected from P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions and Y ions, Contains P ions, Li ions and Cu ions as essential cations, and contains at least O ions as anions, The ratio of the content of O ions to the content of P ions (O ions / P ions) is 3.15 or less, In the glass composition expressed as anion %, the content of O ions is 90.0 anion % or more. In the oxide-based glass composition, On a molar basis, The total content of the oxides of the main cations is 90.0% or more, MgO and Al 2 O 3 Total content (MgO+Al 2 O 3 ) is less than 8.0%, Na 2 O content, K 2 The total of O content and 1 / 2 of ZnO content relative to Li 2 O content ratio ((Na 2 O+K 2 O+ZnO) / Li 2 O) is 2.4 or less, The near-infrared absorbing glass satisfies the following formula 6, Formula 6: C-3478×exp(-2.278×R)≥0 In Formula 6, C is the average CuO content per molar volume of glass (unit: mmol / cc), R is the ratio (O ions / P ions).

7. The near infrared absorbing glass according to any one of claims 1 to 6, in, Na 2 O content, K 2 The total content of O content was less than 15.0 mol%.

8. The near infrared absorbing glass according to any one of claims 1 to 7, in, Al 2 O 3 The content is less than 2.0 mol%.

9. The near infrared absorbing glass according to any one of claims 1 to 8, in, Al 2 O 3 ,La 2 O 3 , Y 2 O 3 and Gd 2 O 3 Total content (Al 2 O 3 +La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) is 0.1 mol % or more.

10. The near infrared absorbing glass according to any one of claims 1 to 9, in, Half value λ T 50 The thickness of the glass reaching 633nm is less than 0.25mm, and the half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at wavelengths above 550nm. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 30% or less.

11. The near infrared absorbing glass according to any one of claims 1 to 9, in, Half value λ T 50 The thickness of the glass reaching 633nm is less than 0.25mm, and the half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at wavelengths above 550nm. At the thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is β1% or less, β1 is a value calculated by the following formula B1, Formula B1: β1＝64×R－170 In the formula B1, R is the ratio (O ions / P ions).

12. The near infrared absorbing glass according to any one of claims 1 to 9, in, As the transmittance characteristic converted to a thickness of 0.11 mm, the half value λ T 50 In the range of 600nm to 650nm, the external transmittance T1200 including reflection loss at a wavelength of 1200nm is less than 30%, and the external transmittance T400 including reflection loss at a wavelength of 400nm is more than 70%, and the half value λ T 50 is the wavelength at which external transmittance including reflection losses reaches 50%.

13. The near infrared absorbing glass according to any one of claims 1 to 9, in, As the transmittance characteristic converted to a thickness of 0.21 mm, the half value λ T 50 In the range of 600nm to 650nm, the external transmittance T1200 including reflection loss at a wavelength of 1200nm is less than 25%, and the external transmittance T400 including reflection loss at a wavelength of 400nm is more than 70%, and the half value λ T 50 is the wavelength at which external transmittance including reflection losses reaches 50%.

14. The near infrared absorbing glass according to any one of claims 1 to 9, in, Half value λ T 50 The thickness of the glass reaching 645nm is less than 0.25mm, and the half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at wavelengths above 550nm. At the above thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is 30% or less.

15. The near infrared absorbing glass according to any one of claims 1 to 9, in, Half value λ T 50 The thickness of the glass reaching 645nm is less than 0.25mm, and the half value λ T 50 is the wavelength at which the external transmittance including reflection loss reaches 50% at wavelengths above 550nm. At the thickness, the external transmittance T600 including reflection loss at a wavelength of 600 nm is 50% or more, and the external transmittance T1200 including reflection loss at a wavelength of 1200 nm is β1% or less, The β1 is a value calculated by the following formula B1: Formula B1: β1＝64×R－170 In the formula B1, R is the ratio (O ions / P ions). 16 . A near infrared cut filter, comprising the near infrared absorbing glass according to claim 1 .

Images