JP7280546B2 - Glass plate and wavelength conversion package using the same - Google Patents

Description

The present invention relates to a glass plate and a wavelength conversion package using the same.

In recent years, light emitting devices using light emitting diodes (LEDs) and laser diodes (LDs) have attracted increasing attention as next-generation light sources to replace fluorescent lamps and incandescent lamps. As an example of such a next-generation light source, a light-emitting device is disclosed that combines an LED that emits blue light and a wavelength conversion member that absorbs part of the light from the LED and converts it into yellow light. This light-emitting device emits white light, which is synthesized light of blue light emitted from the LED and yellow light emitted from the wavelength conversion member. Patent Literature 1 proposes a wavelength conversion member in which phosphor powder is dispersed in low-melting glass.

Further, Patent Document 2 describes a wavelength conversion package formed by enclosing a resin layer in a glass plate. made up of the body. Then, the wavelength conversion package of Patent Document 2 is a method of sealing glass plates together via a sealing material layer by laser irradiation in a state filled with a resin containing a quantum dot phosphor (hereinafter, laser sealing). is made with However, when a wavelength conversion package is produced by laser sealing, cracks may occur in the glass plate and the sealing material layer during laser irradiation. In addition, there is a possibility that the quantum dot phosphor may be thermally deteriorated during laser irradiation.

JP-A-2003-258308 International Publication No. 2012/132232 JP 2011-211439 A

By the way, as a method of sealing the wavelength conversion package, a method of anodic bonding via a metal layer is also conceivable. For example, in Patent Document 3, a metal layer of a first glass wafer having a metal layer formed by a CVD method, a sputtering method, or the like is opposed to a second glass wafer, and a positive voltage is applied to the metal layer. , by applying a negative voltage to the second glass wafer, the metal layer and the second glass wafer are anodically bonded, and the first glass wafer and the second glass wafer are sealed via the metal layer. is stated.

However, the method described in Patent Document 3 has a problem that the first glass wafer and the metal layer are separated when stress is applied between the first glass wafer and the second glass wafer. . In addition, in order to increase the sealing strength by the method described in Patent Document 3, high temperature and/or high applied voltage are required during anodic bonding, and the quantum dot phosphor in the wavelength conversion package thermally deteriorates. There is fear.

Accordingly, the present invention has been made in view of the above circumstances, and its technical problem is to provide a glass plate in which peeling of the metal layer hardly occurs during anodic bonding and which can be anodic bonded at a low temperature and/or a low applied voltage. And to invent a wavelength conversion package using this.

As a result of repeating various experiments, the present inventors found that the above technical problems can be solved by strictly controlling the glass composition and thermal expansion coefficient of the glass plate, and proposed the present invention. be. That is, the glass plate of the present invention contains 40 to 75% by mass of SiO ₂ , 8 to 30% by mass of Al ₂ O ₃ and 8 to 25% by mass of Na ₂ O as a glass composition, and is heated at 30 to 380°C. It is characterized by having an expansion coefficient of 60×10 ⁻⁷ /° C. or more and being used for anodic bonding. Here, the "thermal expansion coefficient at 30 to 380° C." can be measured, for example, with a dilatometer.

The glass plate of the present invention contains 8% by mass or more of Al ₂ O ₃ and 8% by mass of Na ₂ O in the glass composition. This makes it easier for Na ions to move in the non-bridging oxygen in the glass skeleton, making it easier to perform anodic bonding at a low temperature and/or a low applied voltage. For example, anodic bonding can be easily performed under the conditions of a heating temperature of 80 to 150° C. and an applied voltage of 500V.

Also, the glass plate of the present invention has a thermal expansion coefficient of 60×10 ⁻⁷ /° C. or higher. This reduces the difference in thermal expansion between the glass plate and the metal frame, making it difficult for the metal frame (metal layer) to separate during anodic bonding. In particular, when the metal frame is made of Al (thermal expansion coefficient at 0 to 380° C.: 190×10 ⁻⁷ to 210×10 ⁻⁷ /° C.), the effect is enhanced.

Further, the glass plate of the present invention preferably contains 45 to 70% by mass of SiO ₂ , 12 to 30% by mass of Al ₂ O ₃ and 12 to 20% by mass of Na ₂ O as the glass composition.

Moreover, the glass plate of the present invention preferably has a metal frame on at least one surface.

In the glass plate of the present invention, the metal frame is preferably made of at least one selected from the group consisting of Al, Si, Fe, Ti, Ni, Cr and Cu.

Moreover, it is preferable that the glass plate of the present invention contains a phosphor dispersed in a dispersion medium in a metal frame.

Moreover, the glass plate of the present invention preferably has an electrode film on at least one surface.

In the glass plate of the present invention, the electrode film is preferably made of at least one selected from the group consisting of Al, Si, Fe, Ti, Ni, Cr and Cu.

A wavelength conversion package of the present invention is a wavelength conversion package in which a first glass plate and a second glass plate are anodically bonded via a metal frame, and the first glass plate is the above glass plate. , a phosphor dispersed in a dispersion medium is accommodated in a space surrounded by the first glass plate, the second glass plate, and the metal frame, and the phosphor is excited by incidence of excitation light Fluorescence is preferably emitted by

FIG. 1 is a conceptual cross-sectional view showing an example of the wavelength conversion package of the present invention. As can be seen from FIG. 1 , the wavelength conversion package 1 has a first glass plate 10 and a second glass plate 11 bonded together via a metal frame 12 . The metal frame 12 has a frame-like shape in plan view in the thickness direction, and is formed on the surface 10a of the first glass plate 10 by sputtering or the like. , a second glass plate 11 is arranged. Further, in the space surrounded by the first glass plate 10, the second glass plate 11 and the side wall 12b of the metal frame 12, that is, the space inside the picture frame, the phosphor 13 dispersed in the dispersion medium is accommodated. It is

Further, in the wavelength conversion package of the present invention, the second glass plate is preferably the glass plate described above.

It is a cross-sectional conceptual diagram which shows an example of the wavelength conversion package of this invention. It is a cross-sectional conceptual diagram for demonstrating an example of anodic bonding.

The glass plate of the present invention contains 40 to 75% by mass of SiO ₂ , 8 to 30% by mass of Al ₂ O ₃ and 8 to 25% by mass of Na ₂ O as a glass composition. The reason why the content range of each component is limited as described above will be explained below. In addition, in description of the content range of each component, the following % display points out the mass %, unless there is a special notice.

SiO ₂ is a component that forms a glass network, and its content is 40-75%, preferably 45-70%, 50-68%, 55-65%, especially 60-63%. If the content of SiO ₂ is too small, vitrification becomes difficult and the coefficient of thermal expansion becomes unduly high, so the thermal shock resistance tends to decrease. On the other hand, if the content of _SiO2 is too high, meltability, moldability, and coefficient of thermal expansion tend to decrease.

Al ₂ O ₃ is a component that increases the amount of non-bridging oxygen in the glass skeleton to enhance anodic bondability, and is also a component that enhances Young's modulus. However, if the Al ₂ O ₃ content is too high, devitrified crystals are likely to precipitate in the glass, making it difficult to form a plate. In addition, meltability and thermal expansion coefficient tend to decrease. Therefore, the upper limit range of Al ₂ O ₃ is 30% or less, preferably 28% or less, 24% or less, 23% or less, 22% or less, 21.5% or less, particularly 21% or less, and the lower limit range is It is 8% or more, preferably 10% or more, 12% or more, 15% or more, 17% or more, particularly 18% or more.

Na ₂ O is a component that enhances anodic bondability and a component that enhances the coefficient of thermal expansion. However, if the content of Na ₂ O is too large, the balance of the glass composition may be lost and devitrification resistance may be lowered. The content of Na ₂ O is thus 8-25%, preferably 10-25%, 11-22%, 12-20%, 13-19%, especially 14-18%.

In addition to the above components, for example, the following components may be introduced.

B ₂ O ₃ is a component that lowers the liquidus temperature, high-temperature viscosity, and density. The content of B ₂ O ₃ is therefore preferably 0-6%, 0-4%, 0.1-3%, 0.1-2%, in particular 0.5-1%.

Li ₂ O is a component that lowers high-temperature viscosity and improves meltability and moldability. It is also a component that increases the coefficient of thermal expansion. However, if the content of Li ₂ O is too large, the devitrification resistance tends to decrease. Therefore, the content of Li ₂ O is preferably 0 to 8%, 0 to 5%, 0 to less than 3%, 0 to 2%, 0 to less than 1%, especially 0.01 to less than 0.1%. be.

K ₂ O is a component that lowers high-temperature viscosity, improves meltability and moldability, and increases the coefficient of thermal expansion. However, if the K ₂ O content is too high, the strain point may be too low, or the composition of the glass may be out of balance, resulting in a decrease in devitrification resistance. A preferable upper limit range of K ₂ O is 10% or less, 9% or less, 8% or less, 7% or less, particularly 6% or less, and a preferable lower limit range is 0% or more, 0.5% or more, 1% or more. , 2% or more, 3% or more, in particular 4% or more.

P ₂ O ₅ is a component that raises the strain point. However, if the content of P ₂ O ₅ is too high, the glass tends to undergo phase separation, and its water resistance and devitrification resistance tend to deteriorate. The content of P ₂ O ₅ is therefore preferably 0-8%, 0-5%, 0-3%, 0-2%, especially 0-1%.

The total amount of MgO, CaO, SrO and BaO is preferably 0-15%, 0-9%, 0.5-6%, especially 1-5%. If the total amount of MgO, CaO, SrO and BaO is too large, the density tends to be unduly high and the devitrification resistance tends to decrease.

The mass ratio (MgO+CaO+SrO+BaO)/(Li ₂ O+Na ₂ O+K ₂ O) is preferably 0.5 or less, 0.4 or less, particularly 0.3 or less, in order to increase devitrification resistance. In addition, "(MgO + CaO + SrO + BaO) / (Li ₂ O + Na ₂ O + K ₂ O)" is a value obtained by dividing the total amount of MgO, CaO, SrO and BaO by the total amount of Li ₂ O, Na ₂ O and K ₂ O. .

ZnO is a component that lowers the high-temperature viscosity without lowering the low-temperature viscosity. However, if the ZnO content is too high, the glass tends to undergo phase separation or devitrification. Therefore, the content of ZnO is preferably 8% or less, 4% or less, 1% or less, 0.1% or less, particularly 0.01% or less.

ZrO ₂ is a component that increases Young's modulus and strain point, and is a component that decreases high-temperature viscosity. However, if the content of _ZrO2 is too high, the glass tends to devitrify. Thus, the content of ZrO ₂ is preferably 0-10%, 0-5%, 0-3%, 0-1%, 0-0.4%, especially 0-0.1%.

_TiO2 is a component that lowers the high temperature viscosity. However, if the content of TiO ₂ is too high, the glass tends to be colored or devitrified. In particular, the transmittance tends to fluctuate due to the melting atmosphere and raw material impurities. Thus, the content of TiO ₂ is preferably 0-4%, 0-1%, 0-0.1%, in particular 0-0.01%.

_SnO2 is a component useful as a fining agent. However, if the SnO ₂ content is too high, devitrification due to SnO ₂ occurs and the glass tends to be colored. Thus, the SnO ₂ content is preferably 0-3%, 0.01-2%, 0.05-1%, especially 0.1-0.5%.

In addition to SnO ₂ , one or more selected from the group consisting of As ₂ O ₃ , Sb ₂ O ₃ , CeO ₂ , F, SO ₃ and Cl may be contained as a clarifier. However, considering the environment, it is preferable not to add _As2O3 and _Sb2O3 , and the contents of _As2O3 and _{Sb2O3 are} each less _than 0.1%, particularly less _than 0.01% _. is preferred. The CeO ₂ content is preferably less than 0.1%, especially less than 0.01%, in order to increase the transmittance. The F content is less than 0.1%, particularly less than 0.01%, in order to suppress stress relaxation due to a decrease in low-temperature viscosity.

Transition metal oxides such as CoO and NiO are components that color glass. Therefore, the transition metal oxide content is preferably 0.5% or less, 0.1% or less, and particularly 0.05% or less.

Rare earth oxides such as Nb ₂ O ₅ and La ₂ O ₃ are components that increase Young's modulus. However, when the content of the rare earth oxide increases, the raw material cost rises and the devitrification resistance tends to decrease. Therefore, the content of rare earth oxides is preferably 3% or less, 2% or less, less than 1%, 0.5% or less, especially 0.1% or less.

The contents of PbO and Bi ₂ O ₃ are preferably less than 0.1% each in consideration of the environment.

The glass plate of the present invention preferably has the following properties.

The thermal expansion coefficient at 30 to 380° C. is 60×10 ⁻⁷ /° C. or higher, preferably 70×10 ⁻⁷ /° C. or higher, 75×10 ⁻⁷ /° C. or higher, 80×10 ⁻⁷ /° C. or higher, 85 ×10 ^-7 /°C or more, particularly 90 × 10 ^-7 to 120 × 10 ^-7 /°C. If the coefficient of thermal expansion is too low, the difference in thermal expansion between the glass plate and the metal frame becomes large, and the metal frame tends to separate during anodic bonding. In particular, when the metal frame is made of Al (thermal expansion coefficient at 0 to 380° C.: 190×10 ⁻⁷ to 210×10 ⁻⁷ /° C.), this tendency increases.

The density is preferably 2.60 g/cm ³ or less, 2.55 g/cm ³ or less, 2.50 g/cm ³ or less, 2.49 g/cm ³ or less, especially 2.40 to 2.47 g/cm ³ . The lower the density, the lighter the glass sheet can be. If the contents of SiO ₂ , B ₂ O ₃ and P ₂ O ₅ in the glass composition are increased, or the contents of alkali metal oxides, alkaline earth metal oxides, ZnO, ZrO ₂ and TiO ₂ are decreased, , the density tends to decrease.

The temperature at a high temperature viscosity of 10 ^2.5 dPa·s is preferably 1650°C or less, 1620°C or less, particularly preferably 1400 to 1600°C. If the temperature at a high temperature viscosity of 10 ^2.5 dPa·s is too high, the meltability and formability will be lowered, making it difficult to form the molten glass into a plate. Here, the "temperature at a high temperature viscosity of 10 ^2.5 dPa·s" can be measured by, for example, a platinum ball pull-up method.

Liquidus viscosity is preferably 10 ^4.0 dPa·s or more, 10 ^4.4 dPa·s or more, 10 ^4.8 dPa·s or more, 10 ^5.0 dPa·s or more, 10 ^5.3 dPa·s 10 ^5.5 dPa·s or more, 10 ^5.7 dPa·s or more, 10 ^5.8 dPa·s or more, and particularly 10 ^6.0 dPa·s or more. Incidentally, the higher the liquidus viscosity is, the more the devitrification resistance is improved, and the more difficult it is for devitrification lumps to occur during molding. Here, the "liquidus viscosity" refers to a value obtained by measuring the viscosity at the liquidus temperature by the platinum ball pull-up method. The "liquidus temperature" refers to the glass powder that passes through a 30-mesh (500 µm) standard sieve and remains on the 50-mesh (300 µm) in a platinum boat, held in a temperature gradient furnace for 24 hours, and then removed from the platinum boat. , the highest temperature at which devitrification (devitrification lumps) was observed inside the glass by microscopic observation.

The glass plate of the present invention preferably has a metal frame on at least one surface, and more preferably has a metal frame only on one surface. The average height of the metal frame is preferably 10 μm or more, 20 μm or more, particularly 30 μm or more, and 500 μm or less, 300 μm or less, 100 μm or less, particularly 50 μm or less, from the viewpoint of miniaturization of the wavelength conversion package and wavelength conversion efficiency. is. Furthermore, the shape of the metal frame is preferably a frame shape when viewed from above in the thickness direction. By doing so, it becomes easier to accommodate the phosphor dispersed in the dispersion medium in the space surrounded by the glass plate and the metal frame.

Examples of metals forming the metal frame include Al, Si, Fe, Ti, Ni, Cr, and Cu. Among them, Al is most preferable because it has a high reflectance and makes it difficult for excitation light and wavelength-converted light to leak out of the frame. The above metals may be used singly or in combination. Also, an alloy containing two or more of the above metals may be used.

The glass plate of the present invention preferably contains a phosphor dispersed in a dispersion medium in a metal frame. In this way, it becomes easy to apply to a wavelength conversion package.

For example, a quantum dot phosphor can be used as the phosphor. Quantum dot phosphors include Group II-VI compounds and Group III-V compounds. Group II-VI compounds include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, and the like. Group III-V compounds include InP, GaN, GaAs, GaP, AlN, AlP, AlSb, InN, InAs or InSb. At least one selected from these compounds, or a composite of two or more thereof can be used as quantum dots. The composite includes a core-shell structure, for example, a core-shell structure in which the surface of CdSe particles is coated with ZnS.

Phosphors are not limited to quantum dot phosphors, for example, oxide phosphors, nitride phosphors, oxynitride phosphors, chloride phosphors, acid chloride phosphors, sulfide phosphors, Inorganic phosphor particles such as oxysulfide phosphors, halide phosphors, chalcogenide phosphors, aluminate phosphors, halophosphate phosphors, and garnet compound phosphors may also be used.

Resin or low-melting glass is preferable as the dispersion medium. As the resin, for example, a curable resin having translucency such as an ultraviolet curable resin or a thermosetting resin is used. Specifically, for example, epoxy-based resin, acrylic-based resin, silicone-based resin, or the like can be used. If a resin is used as the dispersion medium, the resin can be cured during the anodic bonding. In this case, the manufacturing efficiency and dimensional accuracy of the wavelength conversion package can be improved.

As the low-melting-point glass, for example, borosilicate-based glass, phosphate-based glass, stannate-based glass, bismuthate-based glass, or the like can be used. The borosilicate glass has a glass composition of SiO ₂ 30 to 85%, Al 2 O ₃ 0 to 30%, B ₂ O ₃ 0 to 50% _{, Li 2 O} + Na ₂ O + K ₂ O 0 to 0. 10%, and MgO+CaO+SrO+BaO 0-50%. As the stannous phosphate-based glass, a glass composition containing 30 to 90% SnO and 1 to 70% P ₂ O ₅ in terms of mol % can be mentioned.

A method for manufacturing the glass plate of the present invention is, for example, as follows. First, glass raw materials prepared so as to have a desired glass composition are put into a continuous melting furnace, heated and melted at 1500 to 1650° C., clarified, and then the molten glass is supplied to a forming apparatus and formed into a plate shape. , preferably cooled. A well-known method can be adopted as a method of cutting into a predetermined size after molding into a plate shape.

As a method for forming the molten glass into a plate shape, it is preferable to employ an overflow down-draw method. The overflow down-draw method is a method by which high-quality glass sheets can be produced in large quantities and large-sized glass sheets can also be produced easily. Furthermore, in the overflow down-draw method, an alumina-based refractory or a zirconia-based refractory is used as the compact refractory.

Various molding methods can be employed other than the overflow downdraw method. For example, molding methods such as a float method, a down-draw method (slot down-draw method, redraw method, etc.), a roll-out method, and a press method can be employed.

Subsequently, if necessary, a metal frame is formed on the surface of the glass plate. As a method of forming the metal frame, for example, a CVD method, a sputtering method, a vacuum deposition method, a method of sintering a metal paste, or the like can be adopted.

A wavelength conversion package of the present invention is a wavelength conversion package in which a first glass plate and a second glass plate are anodically bonded via a metal frame, and the first glass plate is the above glass plate. , a phosphor dispersed in a dispersion medium is accommodated in a space surrounded by the first glass plate, the second glass plate, and the metal frame, and the phosphor is excited by incidence of excitation light and emits fluorescence. Moreover, the wavelength conversion package of this invention WHEREIN: It is preferable that a 2nd glass plate is also said glass plate. Since the technical features of the wavelength conversion package of the present invention have already been described in the description of the glass plate of the present invention, detailed description thereof will be omitted here.

FIG. 2 is a conceptual cross-sectional view for explaining an example of anodic bonding. First, after preparing the first glass plate 20 , the metal frame 21 is formed on one surface of the first glass plate 20 . Next, after a phosphor (not shown) dispersed in a dispersion medium is placed in the metal frame 21 , the second glass plate 22 is placed on the metal frame 21 . Furthermore, under the first glass plate 20, a third glass plate 24 having an electrode film 23 provided on one surface thereof is arranged so that the electrode film 23 faces outward, and the second glass plate Above 22, a fourth glass plate 26 provided with an electrode film 25 on one surface is placed with the electrode film 25 on the outside. A voltage is applied between the metal frame 21 and the electrode films 23 and 25 . Specifically, a positive voltage is applied to the metal frame 21 and a negative voltage is applied to the electrode films 23 and 25 . As a result, a negative voltage is applied to the surface of the first glass plate 20 opposite to the metal frame 21 and the surface of the second glass plate 22 opposite to the metal frame 21 . Thereby, the metal frame 21 and the second glass plate 22 are anodically bonded.

The glass plate of the present invention can also be suitably used for the third glass plate 24 and the fourth glass plate 26 shown in FIG. In this case, the glass plate of the present invention preferably has an electrode film on at least one surface, and the electrode film is at least one selected from the group consisting of Al, Si, Fe, Ti, Ni, Cr and Cu. It is preferably composed of one kind.

EXAMPLES The present invention will be described below based on examples. It should be noted that the following examples are merely illustrative. The present invention is by no means limited to the following examples.

Table 1 shows examples of the present invention (samples Nos. 1 to 12) and comparative examples (samples Nos. 13 and 14). In the table, "na" means unmeasured.

次のようにして表中の各試料を作製した。まず表中のガラス組成になるように、ガラス原料を調合し、白金ポットを用いて１６５０℃で２１時間溶融した。続いて、得られた溶融ガラスをカーボン板の上に流し出して、板状に成形した後、徐冷点から歪点の間の温度域を３℃／分で冷却し、ガラス板を得た。得られたガラス板について、板厚が０．８ｍｍになるように表面を光学研磨した後、種々の特性を評価した。

Each sample in the table was prepared as follows. First, glass raw materials were prepared so as to have the glass composition shown in the table, and melted at 1650° C. for 21 hours using a platinum pot. Subsequently, the obtained molten glass was poured onto a carbon plate and formed into a plate shape, and then the temperature range between the annealing point and the strain point was cooled at 3°C/min to obtain a glass plate. . After the surface of the obtained glass plate was optically polished so as to have a plate thickness of 0.8 mm, various properties were evaluated.

The coefficient of thermal expansion is the average value measured with a dilatometer in the temperature range of 30 to 380°C.

Density is a value measured by the well-known Archimedes method.

A strain point is a value measured by the method of ASTM C336.

The temperatures at high-temperature viscosities of 10 ^4.5 dPa·s, 10 ^4.0 dPa·s, 10 ^3.0 dPa·s, and 10 ^2.5 dPa·s are values measured by the platinum ball pull-up method.

A wavelength conversion package was produced as follows. As shown below, four glass plates are used in the manufacturing process of each wavelength conversion package, and these glass plates are the same. In other words, No. In the wavelength conversion package according to No. 1, No. Only the glass plate according to Sample No. 1 is used (the same applies to the wavelength conversion packages according to Sample Nos. 2 to 14).

More specifically, after forming a metal frame made of Al and having a frame shape in plan view in the thickness direction on one surface of the glass plate of each sample, a space surrounded by the glass plate and the metal frame was formed. Then, the phosphor dispersed in the dispersion medium was accommodated to obtain a composite structure. After that, a glass plate of the same size was prepared for each sample and placed so as to overlap the metal frame of the composite composition. Further, two glass plates for each sample having an Al electrode film provided on one surface were prepared and placed on the main surface of the composite structure so that the Al electrode film was on the outside. (See Figure 2). Subsequently, a positive voltage was applied to the metal frame and a negative voltage was applied to each of the two electrode films to obtain various wavelength conversion packages in which the glass plates were anodically bonded to each other. Various wavelength conversion packages were observed with a microscope, and evaluated as "good" when the metal frame was not peeled off, and as "poor" when the metal frame was peeled off. In the anodic bonding, the heating temperature was set to 150° C. and the applied voltage was set to 500V.

Subsequently, a high-temperature, high-humidity, high-pressure test was performed on the obtained wavelength conversion package. Specifically, the obtained wavelength conversion package was subjected to a high-temperature, high-humidity and high-pressure test (temperature: 121°C, relative humidity: 100%, 2 atmospheres, 24 hours), and then the inside of the wavelength conversion package was observed. A sample with no infiltration was evaluated as “◯”, and a sample with water infiltration was evaluated as “x”.

As can be seen from Table 1, sample no. The wavelength conversion packages according to Nos. 1 to 12 had good evaluations of hermetic reliability (metal peeling, high temperature, high humidity, high pressure test). On the other hand, sample no. Since the wavelength conversion package according to No. 13 has a low coefficient of thermal expansion, the evaluation of metal peeling was poor. Moreover, sample no. In the wavelength conversion package according to No. 14, since the content of Al ₂ O ₃ in the glass composition was small, the anodic bonding was insufficient, and the evaluation in the high-temperature, high-humidity, high-pressure test was unsatisfactory.

The glass plate of the present invention is suitable for use in producing wavelength conversion packages containing quantum dot phosphors and the like by anodic bonding. It is also suitable for applications that are produced by bonding.

1 Wavelength conversion packages 10, 20 First glass plates 11, 22 Second glass plates 12, 21 Metal frame 13 Phosphors 23, 25 dispersed in dispersion medium Electrode film

Claims (10)

As a glass composition, in mass %, SiO ₂ 60 to 75%, Al ₂ O ₃ 16.5 to 30%, Na ₂ O 16.5 to 25%, MgO, CaO, SrO and BaO total 0 to 2% and has a thermal expansion coefficient of 75×10 ⁻⁷ /° C. or more at 30 to 380° C., and is used for anodic bonding. As the glass composition, in mass %, SiO ₂ 60 to 75 %, Al ₂ O ₃ 16.5 to 30%, Na ₂ O 16.6 to 20%, MgO, CaO, SrO and BaO total 0 to 2% The glass plate according to claim 1, comprising: As a glass composition, in mass%, SiO ₂ 61.3-75%, Al ₂ O. ₃ 16.5-30% Na ₂ 3. The glass plate according to claim 1, comprising 16.5 to 20% O and 0 to 2% total of MgO, CaO, SrO and BaO. The glass plate according to any one of claims 1 to 3, characterized by having a metal frame on at least one surface. 5. The glass plate according to claim 4, wherein the metal frame is made of at least one selected from the group consisting of Al, Si, Fe, Ti, Ni, Cr and Cu. 6. The glass plate according to claim 4, wherein the metal frame accommodates phosphor dispersed in a dispersion medium. 4. The glass plate according to any one of claims 1 to 3, comprising an electrode film on at least one surface. 8. The glass plate according to claim 7, wherein the electrode film is made of at least one selected from the group consisting of Al, Si, Fe, Ti, Ni, Cr and Cu. A wavelength conversion package in which the first glass plate and the second glass plate are anodically bonded via a metal frame,
The first glass plate is the glass plate according to any one of claims 1 to 5,
A space surrounded by the first glass plate, the second glass plate, and the metal frame contains a phosphor dispersed in a dispersion medium, and the phosphor is excited by incidence of excitation light. A wavelength conversion package, characterized in that it emits fluorescence through a light source. 10. The wavelength conversion package according to claim 9, wherein the second glass plate is the glass plate according to any one of claims 1 to 5.

Images