JP6406571B2 - Glass - Google Patents

Description

  The present invention relates to glass, and more specifically, to a phase separation glass having a light scattering function.

  In recent years, energy consumed in living spaces such as homes has increased due to the widespread use, increase in size, and multifunctionality of home appliances. In particular, the energy consumption of lighting equipment is increasing. For this reason, highly efficient illumination is actively studied.

  Illumination light sources are classified into “directional light sources” that illuminate a limited range and “diffuse light sources” that illuminate a wide range. LED lighting corresponds to a “directional light source” and is being adopted as an alternative to an incandescent bulb. On the other hand, an alternative light source for a fluorescent lamp corresponding to a “diffusion light source” is desired, and organic EL (electroluminescence) illumination is a promising candidate.

  The organic EL element includes a glass plate, a transparent conductive film as an anode, an organic EL layer including an organic compound exhibiting electroluminescence that emits light by current injection, and a cathode, and a cathode. It is an element. As the organic EL layer used in the organic EL element, a low molecular dye material, a conjugated polymer material or the like is used. When forming a light emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection A laminated structure with layers and the like is formed. An organic EL layer having such a laminated structure is disposed between the anode and the cathode, and by applying an electric field to the anode and the cathode, holes injected from the transparent electrode that is the anode and those injected from the cathode The electrons recombine in the light emitting layer, and the emission center is excited by the recombination energy to emit light.

  Organic EL elements have been studied for use in mobile phones and displays, and some have already been put into practical use. In addition, the organic EL element has a luminous efficiency equivalent to that of a thin television such as a liquid crystal display or a plasma display.

  However, in order to apply the organic EL element to the light source for illumination, the luminance has not yet reached the practical level, and further improvement of the light emission efficiency is necessary.

One reason for the decrease in luminance is that light is confined in the glass plate due to the difference in refractive index between the glass plate and air. For example, when a glass plate having a refractive index n _{d of} 1.5 is used, since the refractive index n _{d of} air is 1.0, the critical angle is calculated as 42 ° according to Snell's law. Therefore, light having an incident angle greater than the critical angle causes total reflection, is confined in the glass plate, and is not extracted into the air.

JP 2012-25634 A

  In order to solve the above problem, it has been studied to form a light extraction layer between a transparent conductive film or the like and a glass plate. For example, in Patent Document 1, a light extraction layer in which a glass frit having a high refractive index is sintered is formed on the surface of a soda glass plate, and a scattering substance is dispersed in the light extraction layer, thereby reducing the light extraction efficiency. It is also described to increase.

However, in order to form the light extraction layer on the surface of the glass plate, a printing step of applying a glass paste to the surface of the glass plate is required, and this step causes an increase in production cost. Further, when the scattering particles are dispersed in the glass frit, the transmittance of the light extraction layer is lowered due to the absorption of the scattering particles themselves. Furthermore, since the glass frit described in Patent Document 1 contains a large amount of rare metal oxide such as Nb ₂ O ₅ , the raw material cost is high.

  The present invention has been made in view of the above circumstances, and its technical problem is that the light extraction efficiency of the organic EL element can be increased without forming a light extraction layer made of a sintered body, and The idea is to create a glass plate with excellent productivity.

As a result of intensive studies, the present inventors have found that the above technical problem can be solved by using a specific phase-separated glass, and propose the present invention. That is, the glass of the present invention has a phase separation structure comprising at least a first phase and a second phase, the content of SiO ₂ in the first phase, containing SiO ₂ in the second phase It is more than the amount and is used for an organic EL device. The “organic EL device” includes not only organic EL lighting but also an organic EL display. Moreover, the light scattering accompanying formation of a 1st phase and a 2nd phase can be confirmed visually. For example, each phase can be confirmed in detail by observing the surface of the sample after being immersed in a 1M hydrochloric acid solution for 10 minutes with a scanning electron microscope.

The glass of the present invention has a phase separation structure including at least a first phase and a second phase, and the content of SiO ₂ in the first phase is higher than the content of SiO _{2 in} the second phase. It is also characterized by many. In this way, when applied to an organic EL device, light incident on the glass plate from the organic EL layer is scattered at the interface between the first phase and the second phase, and the light extraction efficiency of the organic EL element is increased. Can be increased.

Secondly, the glass of the present invention has a phase separation structure including at least a first phase and a second phase, and the content of B ₂ O ₃ in the second phase is in the first phase. It is more than the content of B ₂ O ₃ and is characterized by being used for an organic EL device. In this way, when applied to an organic EL device, light incident on the glass plate from the organic EL layer is scattered at the interface between the first phase and the second phase, and the light extraction efficiency of the organic EL element is increased. Can be increased.

Third, the glass of the present invention preferably contains, as a glass composition, 30% to 75% of SiO _2, 0.1 to 50% of B ₂ O ₃ , and 0 to 35% of Al ₂ O ₃ as a glass composition. . If it does in this way, it will become easy to produce phase separation glass and productivity of a glass plate can also be improved.

Fourthly, it is preferable that the glass of this invention does not contain a rare metal oxide substantially in a glass composition. Here, the “rare metal oxide” referred to in the present invention is a rare earth oxide such as La ₂ O ₃ , Nd ₂ O ₃ , Gd ₂ O ₃ , CeO ₂ , Y ₂ O ₃ , Nb ₂ O ₅ , Ta ₂ O. ₅ points. Further, “substantially no rare metal oxide” means that the content of the rare metal oxide in the glass composition is 0.1% by mass or less.

Fifth, the glass of the present invention preferably has a refractive index n _d is 1.50 greater. One of the causes of lowering the brightness is a problem of refractive index mismatch. Specifically, the refractive index _{n d} of the transparent conductive film is 1.9 to 2.0, the refractive index _{n d} of the organic EL layer is 1.8 to 1.9. In contrast, the refractive index _{n d} of the glass plate is usually about 1.5. Therefore, in the conventional organic EL device, light incident from the organic EL layer is reflected at the interface between the glass plate and the transparent conductive film due to a large difference in the refractive index between the glass plate and the transparent conductive film. There was a problem that the extraction efficiency was lowered. Therefore, if regulating the refractive index n _d of the glass as described above, the refractive index difference between such a glass plate and a transparent conductive film is reduced, the light incident from the organic EL layer at the interface, such as a glass plate and a transparent conductive film It becomes difficult to reflect. Here, “refractive index n _d ” refers to the value of the d-line measured by a refractive index measuring device. For example, a rectangular parallelepiped sample of 25 mm × 25 mm × about 3 mm is first prepared, and is slowly cooled at a cooling rate of 0.1 ° C./min in the temperature range from (annealing point Ta + 30 ° C.) to (strain point Ps−50 ° C.). after, while penetration of immersion the refractive index n _d are aligned, it can be measured by the refractive index measuring instrument KPR-2000 manufactured by Shimadzu Corporation.

  Sixth, it is preferable that the glass of the present invention has a flat plate shape, that is, a glass plate.

  Seventh, the glass of the present invention is preferably formed by an overflow down draw method. If it does in this way, the surface accuracy of a glass plate can be raised. Here, the “overflow down draw method” is a method in which molten glass overflows from both sides of a heat-resistant bowl-shaped structure, and is stretched downward to form a glass plate while joining at the lower end of the bowl-like structure. It is a method to do.

  Eighth, the glass of the present invention is preferably not subjected to a separate heat treatment step, and is preferably phase-separated in the molding step or phase-separated in the slow cooling (cooling) step immediately after molding. If it does in this way, the number of manufacturing processes of glass will decrease and glass productivity can be raised.

  Ninth, the glass of the present invention is preferably used for organic EL lighting.

Tenth, the glass of the present invention preferably has a phase separation viscosity of 10 ^7.0 dPa · s or less. If it does in this way, it will become easy to phase-separate glass at a formation process and / or a slow cooling process, and it will become easy to shape a glass plate which has a phase separation structure by a float process or an overflow down draw method. As a result, after forming the glass plate, a separate heat treatment step becomes unnecessary, and the manufacturing cost of the glass plate can be easily reduced. In addition, although it is preferable that the glass of this invention phase-separates in a shaping | molding process and / or a slow cooling process, glass may be phase-separated by the fusion | melting process besides these processes. Here, the “phase separation viscosity” refers to a value obtained by measuring the viscosity of the glass at the phase separation temperature by the platinum pulling method. “Phase separation temperature” refers to a temperature at which white turbidity is clearly recognized when glass is placed in a platinum boat, remelted at 1400 ° C., then transferred to a temperature gradient furnace, and held in the temperature gradient furnace for 5 minutes. Point to.

  Eleventh, the glass of the present invention preferably has a haze value of 1 to 100% at wavelengths of 435 nm, 546 nm and 700 nm. If it does in this way, since it will become easy to scatter light in glass, it will become easy to take out light outside, and it will become easy to raise light extraction efficiency as a result. Here, the “haze value” is a value calculated by (diffuse transmittance) × 100 / (total light transmittance). “Diffusion transmittance” is a value measured in the thickness direction with a spectrophotometer (for example, UV-2500PC manufactured by Shimadzu Corporation). For example, glass whose both surfaces are mirror-polished can be used as a measurement sample. The “total light transmittance” is a value measured in the thickness direction with a spectrophotometer (for example, UV-2500PC manufactured by Shimadzu Corporation). For example, glass whose both surfaces are mirror-polished can be used as a measurement sample.

Twelfth, the glass of the present invention, when incorporated into the organic EL element, current efficiency, the refractive index n _d is preferably made higher than the glass that is not phase separation of the same extent. Here, “current efficiency” is calculated by preparing a luminance meter in a direction perpendicular to the thickness direction of the glass after measuring the organic EL element using glass and measuring the front luminance of the glass. Can do. “The refractive index _nd is about the same” means that the refractive index _nd is within a range of ± 0.2.

  Thirteenth, the organic EL device of the present invention is characterized by comprising the above glass.

  14thly, the composite substrate of this invention is a composite substrate which joined the glass plate and the board | substrate, Comprising: A glass plate consists of said glass, It is characterized by the above-mentioned. In this way, since the glass plate functions as a light scattering layer, the light extraction efficiency of the organic EL element can be increased only by combining with the substrate. Furthermore, if the glass plate and the substrate are joined and the glass plate is disposed on the side in contact with the air, the scratch resistance of the composite substrate can be improved.

  Fifteenth, in the composite substrate of the present invention, the substrate is preferably a glass substrate. A glass substrate is superior in permeability, weather resistance, and heat resistance compared to a resin substrate or a metal substrate.

The sixteenth, the composite substrate of the present invention, it preferably has a refractive index n _d of the substrate is 1.50 greater. In this way, since reflection at the interface between the organic EL layer and the substrate is suppressed, light in the substrate can be easily taken out into the air.

  Seventeenth, in the composite substrate of the present invention, it is preferable that the glass plate and the substrate are joined by optical contact. In this way, since the adhesive tape and the curing agent are not required for joining, the transmittance of the composite substrate is improved, and the glass plate and the substrate can be joined easily. Note that the higher the surface accuracy (flatness) of the surface on the bonding side of the glass plate and the substrate, the higher the bonding strength of the optical contact.

  Eighteenth, the composite substrate of the present invention is preferably used for an organic EL device.

Sample No. 2 according to [Example 2] 2 is an image obtained by immersing 2 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 9 is an image obtained by immersing 9 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 10 is an image obtained by immersing 10 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 11 is an image obtained by immersing 11 in a 1 M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 12 is an image obtained by immersing 12 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 13 is an image obtained by observing the obtained surface with a scanning electron microscope after dipping 13 in a 1M hydrochloric acid solution for 10 minutes. Sample No. 2 according to [Example 2] 14 is an image obtained by observing the obtained surface with a scanning electron microscope after 14 was immersed in a 1M hydrochloric acid solution for 10 minutes. Sample No. 2 according to [Example 2] 15 is an image obtained by observing the obtained surface with a scanning electron microscope after dipping 15 in a 1M hydrochloric acid solution for 10 minutes. Sample No. 2 according to [Example 2] 16 is an image obtained by immersing 16 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 17 is an image obtained by immersing 17 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 18 is an image obtained by immersing 18 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 19 is an image obtained by immersing 19 in a 1M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. Sample No. 2 according to [Example 2] 20 is an image obtained by immersing 20 in a 1 M hydrochloric acid solution for 10 minutes and then observing the obtained surface with a scanning electron microscope. According to Sample No. 4 related to [Example 4]. 12 is a data showing a current efficiency curve for comparing 12 with a comparative example.

The glass of the present invention has a phase separation structure including at least a first phase and a second phase, and the content of SiO ₂ in the first phase is higher than the content of SiO _{2 in} the second phase. many, also the content of B ₂ O ₃ in the second phase is greater than the content of B ₂ O ₃ in the first phase. If it does in this way, the refractive index of a 1st phase and a 2nd phase will become easy to differ, and the scattering function of glass can be improved.

  The average particle size of the phase-separated particles of at least one phase (first phase and / or second phase) is preferably 0.1 to 5 μm. If the average particle size of the phase-separated particles is smaller than 0.1 μm, the light emitted from the organic EL layer is difficult to scatter at the interface between the first phase and the second phase. Further, due to Rayleigh scattering, different scattering intensities are shown depending on the wavelength. As a result, it is necessary to optimize the element configuration of the light emitting layer when manufacturing a white OLED. On the other hand, if the average particle size of the phase-separated particles is larger than 5 μm, the scattering intensity becomes too strong and the total light transmittance may be lowered.

The glass of the present invention preferably contains, as a glass composition, 30 to 75% of SiO _2, 0.1 to 50% of B ₂ O ₃ , and 0 to 35% of Al ₂ O ₃ , and SiO ₂ 39 ultra _{~75%, B 2 O 3 10~40} %, and particularly preferably contains _Al less than 2 O 3 10~23%. If it does in this way, phase separation will improve and it will become easy to raise a light-scattering function. Hereinafter, the reason why each component is limited as described above will be described. In addition, in description of the containing range of each component,% display means the mass%.

The content of SiO ₂ is preferably 30 to 75%. When the content of SiO ₂ increases, the meltability and moldability tend to decrease, and the refractive index tends to decrease. Therefore, the preferable upper limit range of SiO ₂ is 75% or less, 70% or less, 65% or less, and particularly 60% or less. On the other hand, when the content of SiO ₂ decreases, it becomes difficult to form a glass network structure, and vitrification becomes difficult. Further, the viscosity of the glass is excessively lowered, and it becomes difficult to ensure a high liquid phase viscosity. Therefore, the preferable lower limit range of SiO ₂ is 30% or more, 35% or more, 38% or more, more than 39%, particularly 40% or more.

The content of B ₂ O ₃ is preferably 0.1 to 50%. B ₂ O ₃ is a component that enhances phase separation, but if the content of B ₂ O ₃ is too large, the component balance of the glass composition is impaired, and devitrification resistance is likely to decrease. The acid resistance tends to decrease. Therefore, the preferable upper limit range of B ₂ O ₃ is 50% or less, 40% or less, 30% or less, particularly 25% or less, and the preferable lower limit range is 0.1% or more, 0.5% or more, 1%. These are 4% or more, 7% or more, 10% or more, 12% or more, 14% or more, 16% or more, 18% or more, 20% or more, particularly 22% or more.

The content of Al ₂ O ₃ is preferably 0 to 35%. Al ₂ O ₃ is a component that enhances devitrification resistance. However, if the content of Al ₂ O ₃ is too large, the phase separation is liable to decrease, and the component balance of the glass composition is impaired. Conversely, devitrification resistance tends to decrease. Moreover, acid resistance tends to decrease. Therefore, the preferred upper limit range of Al ₂ O ₃ is 35% or less, 30% or less, 25% or less, less than 23%, particularly 20% or less, and the preferred lower limit range is 0.1% or more, 3% or more, 5% or more, 8% or more, 10% or more, 12% or more, 14% or more, particularly 15% or more.

From the viewpoint of achieving both devitrification resistance and phase separation, the content of SiO ₂ —Al ₂ O ₃ —B ₂ O ₃ is preferably −10 to 30%, −5 to 25%, particularly 0 to 20%. Yes, the content of Al ₂ O ₃ + B ₂ O ₃ is preferably 25 to 50%, 29 to 45%, particularly 32 to 40%, and the mass ratio SiO ₂ / (Al ₂ O ₃ + B ₂ O ₃ ) Is preferably 0.7 to 2.6, 0.8 to 2, in particular 0.85 to 1.6. “SiO ₂ —Al ₂ O ₃ —B ₂ O ₃ ” is obtained by reducing the content of Al ₂ O ₃ from the content of SiO ₂ and further reducing the content of B ₂ O ₃ . “Al ₂ O ₃ + B ₂ O ₃ ” is the total content of Al ₂ O ₃ and B ₂ O ₃ . “SiO ₂ / (Al ₂ O ₃ + B ₂ O ₃ )” is a value obtained by dividing the content of SiO ₂ by the total content of Al ₂ O ₃ and B ₂ O ₃ .

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

The content of Li ₂ O is preferably 0 to 30%. Li ₂ O is a component that enhances phase separation. However, if the content of Li ₂ O is too large, the liquid phase viscosity tends to decrease and the strain point tends to decrease. Furthermore, the alkali component is easily eluted in the acid etching step. Therefore, the preferable upper limit range of Li ₂ O is 30% or less, 20% or less, 10% or less, 5% or less, 1% or less, particularly 0.5% or less.

The content of Na ₂ O is preferably 0 to 30%. Na ₂ O is a component that enhances the phase separation. However, when the content of Na ₂ O is too large, the liquid phase viscosity tends to decrease and the strain point tends to decrease. Furthermore, the alkali component is easily eluted in the acid etching step. Therefore, the preferable upper limit range of Na ₂ O is 30% or less, 20% or less, 10% or less, 5% or less, 1% or less, particularly 0.5% or less.

The content of K ₂ O is preferably 0 to 30%. K ₂ O is a component that enhances phase separation. However, if the content of K ₂ O is too large, the liquid phase viscosity tends to decrease and the strain point tends to decrease. Furthermore, the alkali component is easily eluted in the acid etching step. Therefore, a preferable upper limit range of K ₂ O is 30% or less, 20% or less, 10% or less, 5% or less, 1% or less, particularly 0.5% or less.

  The content of MgO is preferably 0 to 30%. MgO is a component that raises the refractive index, Young's modulus, and strain point and lowers the high-temperature viscosity. However, when MgO is contained in a large amount, the liquidus temperature rises and devitrification resistance decreases. Or the density may become too high. Therefore, a preferable upper limit range of MgO is 30% or less, 20% or less, particularly 10% or less, and a preferable lower limit range is 0.1% or more, 1% or more, 3% or more, particularly 5% or more.

  The content of CaO is preferably 0 to 30%. CaO is a component that lowers the high-temperature viscosity. However, when the content of CaO increases, the density tends to increase, and the balance of components of the glass composition is impaired, and devitrification resistance tends to decrease. Therefore, a preferable upper limit range of CaO is 30% or less, 20% or less, 10% or less, 5% or less, particularly 3% or less, and a preferable lower limit range is 0.1% or more, 0.5% or more, particularly 1% or more.

  The content of SrO is preferably 0 to 30%. If the SrO content is increased, the refractive index and the density are likely to be increased, and the balance of components of the glass composition is impaired, so that the devitrification resistance is likely to be lowered. Therefore, the preferable upper limit range of SrO is 30% or less, 20% or less, particularly 10% or less, and the preferable lower limit range is 1% or more, 3% or more, particularly 5% or more.

  BaO is a component that increases the refractive index of alkaline earth metal oxides without extremely reducing the viscosity of the glass. When the content of BaO is increased, the refractive index and the density are likely to be increased, and the component balance of the glass composition is impaired, and the devitrification resistance is likely to be lowered. Therefore, the preferable upper limit range of BaO is 40% or less, 30% or less, 20% or less, 10% or less, particularly 5% or less, and the preferable lower limit range is 0.1% or more, particularly 1% or more.

  ZnO is a component that raises the refractive index and strain point and is a component that lowers the high-temperature viscosity. However, when ZnO is introduced in a large amount, the liquidus temperature rises and devitrification resistance tends to be lowered. Therefore, a preferable upper limit range of ZnO is 20% or less, 10% or less, 5% or less, particularly 3% or less, and a preferable lower limit range is 0.1% or more, particularly 1% or more.

TiO ₂ is a component that increases the refractive index, and its content is preferably 0 to 20%. However, when the content of TiO ₂ is increased, the component balance of the glass composition is impaired, and the devitrification resistance is easily lowered. In addition, the total light transmittance may be reduced. Therefore, the preferable upper limit range of TiO ₂ is 20% or less, 10% or less, particularly 5% or less, and the preferable lower limit range is 0.001% or more, 0.01% or more, 0.1% or more, 1%. Above, 2% or more, especially 3% or more.

ZrO ₂ is a component that increases the refractive index, and its content is preferably 0 to 20%. However, when the content of ZrO ₂ increases, the component balance of the glass composition is impaired, and the devitrification resistance is likely to decrease. Therefore, the preferable upper limit range of ZrO ₂ is 20% or less, 10% or less, particularly 5% or less, and the preferable lower limit range is 0.001% or more, 0.01% or more, 0.1% or more, 1%. Above, 2% or more, especially 3% or more.

La ₂ O ₃ is a component that increases the refractive index, and its content is preferably 0 to 10%. When the content of La ₂ O ₃ increases, the density tends to increase, and the devitrification resistance and acid resistance easily decrease. Furthermore, the raw material cost rises, and the manufacturing cost of the glass plate is likely to rise. Therefore, a suitable upper limit range of La ₂ O ₃ is 10% or less, 5% or less, 3% or less, 2.5% or less, 1% or less, particularly 0.1% or less.

Nb ₂ O ₅ is a component that increases the refractive index, and its content is preferably 0 to 10%. When the content of Nb ₂ O ₅ increases, the density tends to increase and the devitrification resistance tends to decrease. Furthermore, the raw material cost rises, and the manufacturing cost of the glass plate is likely to rise. Therefore, a preferable upper limit range of Nb ₂ O ₅ is 10% or less, 5% or less, 3% or less, 2.5% or less, 1% or less, particularly 0.1% or less.

Gd ₂ O ₃ is a component that increases the refractive index, and its content is preferably 0 to 10%. When the content of Gd ₂ O ₃ is increased, the density becomes too high, the component balance of the glass composition is lacking, the devitrification resistance is lowered, the high temperature viscosity is lowered too much, and a high liquid phase viscosity is secured. It becomes difficult to do. Therefore, a suitable upper limit range of Gd ₂ O ₃ is 10% or less, 5% or less, 3% or less, 2.5% or less, 1% or less, particularly 0.1% or less.

The content of La ₂ O ₃ + Nb ₂ O ₅ is preferably 0 to 10%. When the content of La ₂ O ₃ + Nb ₂ O ₅ is increased, the density and the thermal expansion coefficient are likely to be increased, the devitrification resistance is likely to be lowered, and further, it is difficult to ensure a high liquid phase viscosity. Furthermore, the raw material cost rises, and the manufacturing cost of the glass plate is likely to rise. Therefore, a suitable upper limit range of La ₂ O ₃ + Nb ₂ O ₅ is 10% or less, 8% or less, 5% or less, 3% or less, 1% or less, 0.5% or less, particularly 0.1% or less. . Here, “La ₂ O ₃ + Nb ₂ O ₅ ” refers to the total content of La ₂ O ₃ and Nb ₂ O ₅ .

  The total content of rare metal oxides is preferably 0 to 10%. When the content of the rare metal oxide is increased, the density and the thermal expansion coefficient are likely to be increased, and the devitrification resistance and the acid resistance are liable to be lowered, so that it is difficult to ensure a high liquid phase viscosity. Furthermore, the raw material cost rises, and the manufacturing cost of the glass plate is likely to rise. Therefore, the preferable upper limit range of the rare metal oxide is 10% or less, 5% or less, 3% or less, particularly 1% or less, and it is desirable that the rare metal oxide is not substantially contained.

As a refining agent, one or two or more selected from the group of As ₂ O ₃ , Sb ₂ O ₃ , SnO ₂ , Fe ₂ O ₃ , F, Cl, SO ₃ , and CeO ₂ are converted into the following oxides. ~ 3% can be introduced. In particular, SnO ₂ , Fe ₂ O ₃ and CeO ₂ are preferable as the fining agent. On the other hand, it is preferable to refrain from using As ₂ O ₃ and Sb ₂ O ₃ as much as possible from an environmental viewpoint, and the content of each is preferably less than 0.3%, particularly preferably less than 0.1%. Here, “the following oxide conversion” means that an oxide having a valence different from the indicated oxide is handled after being converted to the indicated oxide.

The content of SnO ₂ is preferably 0 to 1%, 0.001 to 1%, particularly 0.01 to 0.5%.

Suitable lower limit ranges of Fe ₂ O ₃ are 0.05% or less, 0.04% or less, 0.03% or less, particularly 0.02% or less, and a preferred lower limit range is 0.001% or more.

The content of CeO ₂ is preferably 0 to 6%. When the content of CeO ₂ is increased, the devitrification resistance is likely to be lowered. Therefore, the preferable upper limit range of CeO ₂ is 6% or less, 5% or less, 3% or less, 2% or less, 1% or less, particularly 0.1% or less. On the other hand, when the CeO ₂ content is reduced, the clarity is likely to be lowered. Therefore, when CeO ₂ is introduced, a preferable lower limit range of CeO ₂ is 0.001% or more, particularly 0.01% or more.

  PbO is a component that lowers the high-temperature viscosity, but it is preferable to refrain from using it as much as possible from an environmental point of view. The content of PbO is preferably 0.5% or less, and is desirably substantially free. Here, “substantially does not contain PbO” refers to a case where the content of PbO in the glass composition is less than 0.1%.

  In addition to the above components, other components may be introduced in a total amount of preferably 10% (desirably 5%).

In the glass of the present invention, the refractive index _nd is preferably more than 1.50, 1.51 or more, 1.52 or more, 1.53 or more, 1.54 or more, 1.55 or more, 1.56 or more, particularly 1.57 or more. When the refractive index _nd is 1.50 or less, it becomes difficult to efficiently extract light due to reflection at the interface between the glass plate and the transparent conductive film. On the other hand, when the refractive index _nd is too high, the reflectance at the interface between the glass plate and the air becomes high, and it becomes difficult to extract light to the outside. Therefore, the refractive index _{n d} is preferably 2.30 or less, 2.20 or less, 2.10 or less, 2.00 or less, 1.90 or less, 1.80 or less, particularly 1.75 or less.

The density is preferably 5.0 g / cm ³ or less, 4.5 g / cm ³ or less, 3.0 g / cm ³ or less, particularly 2.8 g / cm ³ or less. In this way, the device can be reduced in weight.

  The strain point is preferably 450 ° C. or higher, 500 ° C. or higher, particularly 550 ° C. or higher. The higher the temperature of the transparent conductive film, the higher the transparency and the lower the electrical resistance. However, since the conventional glass plate has insufficient heat resistance, it has been difficult to form a transparent conductive film at a high temperature. Therefore, when the strain point is in the above range, it is possible to achieve both transparency of the transparent conductive film and low electric resistance, and further, in the device manufacturing process, the glass plate is hardly thermally contracted by heat treatment.

The temperature at 10 ^2.5 dPa · s is preferably 1600 ° C. or lower, 1560 ° C. or lower, 1500 ° C. or lower, particularly 1450 ° C. or lower. If it does in this way, since a meltability will improve, productivity of a glass plate will improve.

The liquidus temperature is preferably 1300 ° C. or lower, 1250 ° C. or lower, 1200 ° C. or lower, particularly 1150 ° C. or lower. The liquid phase viscosity is preferably 10 ^2.5 dPa · s or more, 10 ^3.0 dPa · s or more, 10 ^3.5 dPa · s or more, 10 ^3.8 dPa · s or more, 10 ^4.0 dPa or more. S or more, 10 ^4.4 dPa · s or more, particularly 10 ^4.6 dPa · s or more. If it does in this way, it will become difficult to devitrify glass at the time of shaping | molding, for example, it will become easy to shape | mold a glass plate by the float method or the overflow downdraw method. Here, “liquid phase temperature” refers to a temperature gradient furnace in which glass is crushed, passed through a standard sieve 30 mesh (a sieve opening of 500 μm), and glass powder remaining in a 50 mesh (a sieve opening of 300 μm) is placed in a platinum boat. It is held for 24 hours and indicates the value at which the temperature at which crystals precipitate is measured. The “liquid phase viscosity” indicates the viscosity of each glass at the liquid phase temperature.

The phase separation temperature is preferably 800 ° C. or higher, particularly 900 ° C. or higher. The phase separation viscosity is preferably 10 ^7.0 dPa · s or less, particularly 10 ^3.0 to 10 ^6.0 dPa · s. If it does in this way, it will become easy to phase-separate glass at a formation process and / or a slow cooling process, and it will become easy to shape a glass plate which has a phase separation structure by a float process or an overflow down draw method. As a result, after forming the glass plate, a separate heat treatment step becomes unnecessary, and the manufacturing cost of the glass plate can be easily reduced.

  The total light transmittance at a wavelength of 435 nm is preferably 5% or more, 10% or more, particularly 30 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The total light transmittance at a wavelength of 546 nm is preferably 5% or more, 10% or more, 30% or more, particularly 50 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The total light transmittance at a wavelength of 700 nm is preferably 5% or more, 10% or more, 30% or more, 50% or more, particularly 70 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The diffuse transmittance at a wavelength of 435 nm is preferably 5% or more, particularly 10 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The diffuse transmittance at a wavelength of 546 nm is preferably 5% or more, 10% or more, particularly 20 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The diffuse transmittance at a wavelength of 700 nm is preferably 1% or more, 5% or more, particularly 10 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The haze value at a wavelength of 435 nm is preferably 5% or more, 10% or more, 30% or more, 50% or more, particularly 70 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved. The “haze value” is a value of diffuse transmittance / total light transmittance × 100.

  The haze value at a wavelength of 546 nm is preferably 5% or more, 10% or more, 30% or more, 50% or more, particularly 70 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The haze value at a wavelength of 700 nm is preferably 1% or more, 5% or more, particularly 10 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The total light transmittance at wavelengths of 435 nm, 546 nm and 700 nm is preferably 1% or more, 3% or more, particularly 10 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The diffuse transmittance at wavelengths of 435 nm, 546 nm and 700 nm is preferably 1% or more, 3% or more, particularly 10 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  The haze values at wavelengths of 435 nm, 546 nm and 700 nm are preferably 1% or more, 3% or more, particularly 10 to 100%. If it does in this way, when an organic EL element is assembled, light extraction efficiency can be improved.

  In the glass of the present invention, the thickness (in the case of a flat plate) is preferably 1.5 mm or less, 1.3 mm or less, 1.1 mm or less, 0.8 mm or less, 0.6 mm or less, 0.5 mm or less, 0.3 mm or less, 0.2 mm or less, particularly 0.1 mm or less. The smaller the plate thickness, the higher the flexibility and the easier it is to produce an organic EL illumination with excellent design, but the glass tends to break when the plate thickness becomes extremely small. Therefore, the plate thickness is preferably 10 μm or more, particularly 30 μm or more.

  The glass of the present invention preferably has a flat plate shape, that is, a glass plate. If it does in this way, it will become easy to apply to an organic EL device. When it has a flat plate shape, it is preferable to have an unpolished surface on at least one surface (in particular, the entire effective surface of at least one surface is an unpolished surface). The theoretical strength of glass is very high, but breakage often occurs even at a stress much lower than the theoretical strength. This is because a small defect called Griffith flow is generated on the surface of the glass in a post-molding process such as a polishing process. Therefore, if the surface of the glass plate is unpolished, the original mechanical strength is hardly lost, and thus the glass plate is difficult to break. Further, since the polishing step can be simplified or omitted, the manufacturing cost of the glass plate can be reduced.

  When it has a flat plate shape, the surface roughness Ra of at least one surface (particularly the unpolished surface) is preferably 0.01 to 1 μm. When the surface roughness Ra is larger than 1 μm, when a transparent conductive film or the like is formed on the surface, the quality of the transparent conductive film is lowered and it becomes difficult to obtain uniform light emission. Suitable upper limit ranges of the surface roughness Ra are 1 μm or less, 0.8 μm or less, 0.5 μm or less, 0.3 μm or less, 0.1 μm or less, 0.07 μm or less, 0.05 μm or less, 0.03 μm or less, particularly 10 nm. It is as follows.

  The glass of the present invention is preferably formed by a downdraw method, particularly an overflow downdraw method. In this way, it is possible to produce a glass plate that is unpolished and has good surface quality. The reason is that, in the case of the overflow down draw method, the surface to be the surface is not in contact with the bowl-shaped refractory and is molded in a free surface state. The structure and material of the bowl-shaped structure are not particularly limited as long as desired dimensions and surface accuracy can be realized. Further, there is no particular limitation on the method for applying force to the molten glass in order to perform downward stretching. For example, a method of rotating and stretching a heat-resistant roll having a sufficiently large width in contact with the molten glass may be adopted, or a plurality of pairs of heat-resistant rolls may be used only in the vicinity of the end face of the molten glass. You may employ | adopt the method of making it contact and extending | stretching. In addition to the overflow downdraw method, a slot downdraw method can be employed. If it does in this way, it will become easy to produce a glass plate with small board thickness. Here, the “slot down draw method” is a method of forming a glass plate by drawing downward from a substantially rectangular gap while drawing molten glass.

  In addition to the above molding method, for example, a redraw method, a float method, a roll-out method, or the like can be employed. In particular, the float process can efficiently produce a large glass plate.

When the glass plate of the present invention has a flat plate shape, at least one surface may be a roughened surface. If the roughened surface is arranged on the side in contact with air such as organic EL lighting, in addition to the scattering effect of the glass plate, the non-reflective structure of the roughened surface allows light emitted from the organic EL layer to be within the organic EL layer. As a result, the light extraction efficiency can be increased. The surface roughness Ra of the roughened surface is preferably 10 mm or more, 20 mm or more, 30 mm or more, particularly 50 mm or more. The roughened surface can be formed by HF etching, sandblasting, or the like. Moreover, you may form an uneven | corrugated shape in the surface of a glass plate by heat processing, such as a repress. In this way, an accurate non-reflective structure can be formed on the glass surface. Uneven shape, taking into account the refractive index n _d, may be adjusted the spacing and depth.

Further, the roughened surface can be formed by an atmospheric pressure plasma process. In this way, it is possible to uniformly roughen the other surface while maintaining the surface state of one surface of the glass plate. Moreover, it is preferable to use a gas containing F (for example, SF ₆ , CF ₄ ) as a source of the atmospheric pressure plasma process. In this way, since plasma containing HF gas is generated, the roughened surface can be formed efficiently.

  Furthermore, a roughened surface can be formed on at least one surface during molding of the glass plate. This eliminates the need for a separate roughening process and improves the efficiency of the roughening process.

  In addition, you may affix the resin film which has a predetermined uneven | corrugated shape on the surface of a glass plate, without forming a roughening surface in a glass plate.

  The glass of the present invention is preferably not subjected to a separate heat treatment step, and is preferably phase-separated in the molding step or phase-separated in the slow cooling (cooling) step immediately after molding. In particular, when a glass plate is formed by the overflow downdraw method, a phase separation phenomenon may occur in the bowl-shaped structure, or a phase separation phenomenon may occur during stretch molding or slow cooling. If it does in this way, the number of manufacturing processes of glass will decrease and glass productivity can be raised. The phase separation phenomenon can be controlled by the glass composition, molding conditions, slow cooling conditions, and the like.

When the glass of the present invention is incorporated in an organic EL device, the current efficiency is preferably higher than that of a glass that is not phase-separated. For example, the current efficiency at 10 mA / cm ² is preferably 5% or more, 10% or more, 20% or more, 30% or more, particularly 40% or more higher than that of glass that has not undergone phase separation. In this way, the brightness of the organic EL device can be increased.

The glass of the present invention, when incorporated into the organic EL element, current efficiency, the refractive index n _d is preferably made higher than the glass that is not phase separation of the same extent. For example, the current efficiency at 10 mA / cm ² is the refractive index _{n d} of 5% or more as compared to the glass that is not phase separation of comparable, more than 10%, 20% or more, 30% or more, particularly 40% higher It is preferable to become. In this way, the brightness of the organic EL device can be increased. In particular, even if the existing glass composition is not significantly changed, the luminance of the organic EL device can be increased only by introducing a component that induces phase separation.

  The composite substrate of the present invention is a composite substrate obtained by bonding a glass plate and a substrate, and the glass plate is made of the above glass. In this way, since the glass plate functions as a light scattering layer, the light extraction efficiency of the organic EL element can be increased only by combining with the substrate. Furthermore, if the glass plate and the substrate are joined and the glass plate is disposed on the side in contact with the air, the scratch resistance of the composite substrate can be improved.

  In the composite substrate of the present invention, the thickness of the glass plate is preferably 0.7 mm or less, 0.5 mm or less, 0.4 mm or less, 0.3 mm or less, 0.2 mm or less, particularly 0.01 to 0.1 mm. is there. In this way, the total thickness of the composite substrate can be reduced.

  Various materials can be used as the substrate. For example, a resin substrate, a metal substrate, or a glass substrate can be used. Among these, a glass substrate is preferable from the viewpoints of permeability, weather resistance, and heat resistance. Various materials can be used as the glass substrate. For example, a soda lime glass substrate, an aluminosilicate glass substrate, and an alkali-free glass substrate can be used.

  The thickness of the glass substrate is preferably 0.3 to 3.0 mm, 0.4 to 2.0 mm, particularly more than 0.5 to 1.8 mm from the viewpoint of maintaining strength.

Refractive index _{n d} of the glass substrate is preferably 1.50 greater, 1.51 or more, 1.52 or more, 1.53 or more, particularly 1.54 or more. If the refractive index of the glass substrate is too low, it becomes difficult to efficiently extract light by reflection at the interface of the glass substrate and the transparent conductive film. On the other hand, if the refractive index _nd is too high, the reflectance at the interface between the glass substrate and the glass plate becomes high, and it becomes difficult to extract the light in the glass substrate into the air. Therefore, the refractive index _{n d} is preferably 2.30 or less, 2.20 or less, 2.10 or less, 2.00 or less, 1.90 or less, 1.80 or less, particularly 1.75 or less.

  As for surface roughness Ra of at least one surface (especially unpolished surface) of a glass substrate, 0.01-1 micrometer is preferable. If the surface roughness Ra of the surface is too large, it becomes easy to produce a composite substrate by optical contact. In addition, when a transparent conductive film or the like is formed on the surface, the quality of the transparent conductive film is lowered and uniform. It becomes difficult to obtain luminescence. Therefore, the preferable upper limit range of the surface roughness Ra of at least one surface is 1 μm or less, 0.8 μm or less, 0.5 μm or less, 0.3 μm or less, 0.1 μm or less, 0.07 μm or less, 0.05 μm or less, 0.03 μm or less, particularly 10 nm or less.

  Various methods can be used as a method of bonding the glass plate and the substrate. For example, a method of joining with an adhesive tape, an adhesive sheet, an adhesive, a curing agent, or the like, or a method of joining with an optical contact can be used. Among these, from the viewpoint of increasing the transmittance of the composite substrate, a method of joining with an optical contact is preferable.

  Hereinafter, based on an Example, this invention is demonstrated in detail. The following examples are merely illustrative. The present invention is not limited to the following examples.

  Tables 1 and 2 show Sample No. 1 to 20 are shown.

  First, after preparing a glass raw material so that it might become a glass composition of Table 1, 2, the obtained glass batch was supplied to the glass melting furnace, and it melted at 1500 degreeC for 8 hours. Next, the obtained molten glass was poured onto a carbon plate, formed into a plate shape, and then slowly cooled from the strain point to room temperature over 10 hours. Finally, the obtained glass plate was processed as necessary to evaluate various properties.

  The density ρ is a value measured by a known Archimedes method.

  The strain point Ps is a value measured by the method described in ASTM C336-71. In addition, heat resistance becomes high, so that the strain point Ps is high.

  The annealing point Ta and the softening point Ts are values measured by the method described in ASTM C338-93.

The temperatures at high temperature viscosities of 10 ^4.0 dPa · s, 10 ^3.0 dPa · s, 10 ^2.5 dPa · s, and 10 ^2.0 dPa · s are values measured by the platinum ball pulling method. In addition, it is excellent in a meltability, so that high temperature viscosity is low.

  The liquid phase temperature TL is obtained by crushing glass, passing through a standard sieve 30 mesh (a sieve opening of 500 μm), and putting the glass powder remaining in 50 mesh (a sieve opening of 300 μm) in a platinum boat and placing it in a temperature gradient furnace for 24 hours The temperature at which the crystals are deposited is measured.

  The liquid phase viscosity log ηTL indicates the viscosity of each glass at the liquid phase temperature.

  The phase separation temperature TP is measured at a temperature at which white turbidity is clearly observed when each glass is put into a platinum boat, remelted at 1400 ° C., then transferred to a temperature gradient furnace and held in the temperature gradient furnace for 5 minutes. It is a thing.

  The phase separation viscosity logηTP is obtained by measuring the viscosity of each glass at the phase separation temperature by the platinum ball pulling method.

Refractive index _{n d} is the value of the d-line as determined by the refractive index measuring instrument KPR-2000 manufactured by Shimadzu Corporation. First, a rectangular parallelepiped sample of 25 mm × 25 mm × about 3 mm is prepared, and then subjected to a slow cooling treatment at a cooling rate of 0.1 ° C./min in a temperature range from (slow cooling point Ta + 30 ° C.) to (strain point Ps−50 ° C.). a value refractive index n _d was measured by penetration of immersion liquid to be aligned.

  The phase separation after the molding, for each sample, after slowly forming the molten glass, as described above, and visually observing the obtained sample, "○" An evaluation of “x” was given to a sample that was not transparent due to phase separation and was transparent. Even if the phase separation after molding is evaluated as “x”, it is considered that the glass can be phase-separated in the slow cooling step by adjusting the slow cooling conditions.

  The phase separation after the heat treatment was carried out by heat-treating each sample after molding (900 ° C. for 5 minutes), stretching and forming a strain point measurement sample, and then the obtained sample was visually observed. Was evaluated as “◯”, and those that were not transparent due to phase separation and were transparent were evaluated as “x”.

Sample No. not subjected to the above heat treatment. 2, 9 to 20 were immersed in a 1M hydrochloric acid solution for 10 minutes, and then the sample surface was observed with a scanning electron microscope (S-4300SE, manufactured by Hitachi High-Technologies Corporation). The results are shown in FIGS. 1 to 13 show Sample No. 2 and 9 to 20 show scanning electron microscope images, respectively. As a result, sample no. 2, 9, 10, and 12 to 20 had a phase separation structure, and a phase rich in B ₂ O ₃ (second phase: a layer poor in SiO ₂ ) was eluted with a hydrochloric acid solution. Note that the phase rich in B ₂ O ₃ is eluted by the hydrochloric acid solution, and the phase rich in SiO ₂ is not eluted in the hydrochloric acid solution.

  Sample No. which was not subjected to the heat treatment so that the plate thickness was 1.0 mm or 0.7 mm. After processing 2, 12, and 19, both surfaces were mirror-polished and the total light transmittance and diffuse transmittance in the thickness direction were measured with a spectrophotometer (Shimadzu spectrophotometer UV-2500PC) for the wavelengths in the table. Was measured. The results are shown in Tables 3-5.

Sample No. in Table 2 A glass plate according to No. 12 (plate thickness 0.7 mm: not heat-treated after molding) was produced, and ITO (thickness 100 nm) was deposited as a transparent electrode layer on the surface of the glass plate using a mask. Subsequently, a polymer PEDOT-PSS (thickness 40 nm) as a hole injection layer, α-NPD (thickness 50 nm) as a hole transport layer, and Ir (ppy) ₃ as an organic light emitting layer are doped by 6% by mass on a glass plate. After forming CBP (thickness 30 nm), hole blocking layer BAlq (thickness 10 nm), electron transport layer Alq (thickness 30 nm), LiF (thickness 0.8 nm) as an electron injection layer, and Al (thickness 150 nm) as a counter electrode The inside was sealed and the organic EL element was produced. About the obtained organic EL element, the luminance meter (BM-9 by Topcon Co., Ltd.) was arrange | positioned in the direction perpendicular | vertical to a light emission surface, front luminance was measured, and current efficiency was evaluated. As a comparative example, Sample No. 12 a glass plate that does not undergo phase separation have comparable refractive index n _d for the case of manufacturing the organic EL device incorporates (thickness 0.7 mm) is also measured front luminance in the same manner, the current efficiency evaluated. The results are shown in Table 6 and FIG. The glass of the comparative example, as a glass composition, in _{mass%, SiO 2 49.8%, Al} 2 O 3 23%, B 2 O 3 14%, 6.4% MgO, CaO 1.5%, ZrO _{2 2.7%,} and contains TiO 2 2.6% refractive index _{n d} is 1.54.

As can be seen from Table 6 and FIG. No. 12 had higher current efficiency than the comparative example when the organic EL element was produced. For example, the current efficiency was about 46% higher at 10 mA / cm ² .

An organic EL element substrate was produced using the glass plate (plate thickness 0.7 mm) of the comparative example of [Example 4] that was not phase-separated. Next, on this substrate, a sample of refractive index _{n d} via the immersion liquid 1.54 Table 2 No. 12 was disposed (thickness 0.7 mm: not heat-treated after molding), and the emission intensity of the light emitting surface was measured using an integrating sphere. Compared with the case where the glass plate concerning No. 12 is not arranged, the intensity of the peak wavelength of 520 nm was 1.2 times.

Claims (18)

As a glass composition, in _mass%, contains _{SiO 2 30~75%, B 2 O} 3 14~40%, the _Al 2 O 3 0.1 to 35%,
Have a phase separation structure comprising at least a first phase and a second phase,
And the content of SiO ₂ in the first phase, more than the content of SiO ₂ in the second phase, and glass, which comprises using the organic EL device. As a glass composition, in _mass%, contains _{SiO 2 30~75%, B 2 O} 3 14~40%, the _Al 2 O 3 0.1 to 35%,
Have a phase separation structure comprising at least a first phase and a second phase,
And content of the second of B ₂ O ₃ in the phases, more than the content of B ₂ O ₃ in the first phase, and glass, which comprises using the organic EL device. The glass according to claim 1, wherein the glass composition contains, by mass%, SiO ₂ 30 to 75%, B ₂ O ₃ 16 to 30 %, and Al ₂ O ₃ 5 to 35%.   The glass according to any one of claims 1 to 3, wherein the glass composition contains substantially no rare metal oxide. Glass according to claim 1, the refractive index n _d is equal to or is 1.50 greater.   It is flat plate shape, Glass in any one of Claims 1-5 characterized by the above-mentioned.   The glass according to any one of claims 1 to 6, which is formed by an overflow downdraw method.   The glass according to any one of claims 1 to 7, which has not undergone a separate heat treatment step.   It uses for organic electroluminescent illumination, The glass in any one of Claims 1-8 characterized by the above-mentioned. The glass according to any one of claims 1 to 9, wherein the phase separation viscosity is 10 ^7.0 dPa · s or less.   The glass according to any one of claims 1 to 10, wherein haze values at wavelengths of 435 nm, 546 nm, and 700 nm are 1 to 100%. The glass according to any one of claims 1 to 11, wherein when incorporated in an organic EL device, the current efficiency is higher than that of a non-phase-separated glass having the same refractive index n _d . The organic EL device characterized in that it comprises a glass according to any one of claims 1 to 12. A composite substrate in which a glass plate and a substrate are joined,
A composite substrate, wherein the glass plate is made of the glass according to claim 1.   The composite substrate according to claim 14, wherein the substrate is a glass substrate. Composite substrate according to claim 14 or 15 refractive index n _d of the substrate is characterized by a 1.50 greater.   The composite substrate according to any one of claims 14 to 16, wherein the glass plate and the substrate are joined by optical contact.   The composite substrate according to claim 14, which is used for an organic EL device.