JP2016098118A - Phase-separated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass capable of enhancing light extraction efficiency of an organic EL element and excellent in productivity without forming a light extraction layer consisting of a sintered body.SOLUTION: The phase-separated glass which is separated to different phases, contains, by mass%, SiOof 40 to 75%, AlOof 0.1 to 20% and BOof 10 to 40% as a glass composition and has a higher phase separation temperature than a liquid phase temperature.SELECTED DRAWING: None

Description

  The present invention relates to a phase separation glass, and specifically relates 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.

JP 2012-25634 A

  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.

  In order to solve this 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.

  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 with excellent productivity.

As a result of intensive studies, the present inventors have found that the above technical problem can be solved by regulating the glass composition range of the phase separation glass and increasing the liquid phase viscosity, and propose the present invention. is there. That is, the phase-separated glass of the present invention is a phase-separated glass that is phase-divided into different phases, and has a glass composition of 40% by mass, SiO ₂ 40-75%, and Al ₂ O ₃ 0.1-20%. , B ₂ O ₃ 10 to 40%, and the phase separation temperature is higher than the liquid phase temperature. Here, the “liquid phase temperature” passed through 30 mesh (500 μm sieve opening), and the glass powder remaining in 50 mesh (300 μm sieve opening) was placed in a platinum boat and held in a temperature gradient furnace for 24 hours. After that, the value which measured the temperature which a crystal | crystallization precipitates is pointed out. The “phase separation temperature” is clear after passing through 30 mesh (500 μm sieve opening), putting the glass powder remaining in 50 mesh (300 μm sieve sieve) into a platinum boat and holding it in a temperature gradient furnace for 24 hours. This refers to the temperature at which white cloudiness is observed.

The phase-separated glass of the present invention contains, as a glass composition, by mass%, SiO ₂ 40 to 75%, Al ₂ O ₃ 0.1 to 20%, and B ₂ O ₃ 10 to 40%. Thereby, the phase separation property of glass can be improved. As a result, when applied to an organic EL device, light incident on the glass from the organic EL layer is scattered at the interface of different phases, so that it is easy to extract the light to the outside. As a result, the light extraction layer made of a sintered body The light extraction efficiency can be increased even without forming.

  The phase separation glass of the present invention has a phase separation temperature higher than the liquid phase temperature. If it does in this way, it will become possible to phase-divide glass, without devitrifying crystal | crystallization precipitating at the time of shaping | molding by control of shaping | molding conditions and slow cooling conditions. As a result, a separate heat treatment step for causing phase separation becomes unnecessary, and the production cost of phase separation glass can be reduced.

Secondly, the phase-separated glass of the present invention has a glass composition of 50% by mass, SiO ₂ 50 to 70%, Al ₂ O ₃ 5 to 20%, B ₂ O ₃ 15 to 35%, Li ₂ O + Na ₂ O + K. _{2 O 0~10%, MgO + CaO} 0.1~20%, preferably contains 0~20% SrO + BaO. Here, “Li ₂ O + Na ₂ O + K ₂ O” refers to the total amount of Li ₂ O, Na ₂ O and K ₂ O. “MgO + CaO” refers to the total amount of MgO and CaO. “SrO + BaO” refers to the total amount of SrO and BaO.

  Third, the phase-separated glass of the present invention preferably has a crack resistance of 200 gf or more. If it does in this way, it will become difficult to break a phase-separated glass at the manufacturing process of an organic EL device, and the yield of an organic EL device can be raised. Here, “crack resistance” refers to a load with a crack occurrence rate of 50%. “Crack occurrence rate” refers to a value measured as follows. First, in a constant temperature and humidity chamber maintained at a humidity of 30% and a temperature of 25 ° C., a Vickers indenter set to a predetermined load is driven into the glass surface (optical polishing surface) for 15 seconds, and 15 seconds later, it is generated from the four corners of the indentation. Count the number of cracks (maximum 4 per indentation). In this way, the indenter is driven 50 times to determine the total number of cracks generated, and then determined by the formula (total number of cracks generated / 200) × 100 (%).

Fourthly, the phase separation glass of the present invention preferably has a liquidus viscosity of 10 ^3.5 dPa · s or more. If it does in this way, it will become possible to phase-divide glass effectively, without making a devitrification crystal precipitate at the time of fabrication. As a result, a separate heat treatment step for causing phase separation becomes unnecessary, and the production cost of phase separation glass can be reduced. Here, “liquid phase viscosity” refers to a value obtained by measuring the viscosity of glass at the liquid phase temperature by a platinum ball pulling method.

  Fifth, the phase separation glass of the present invention preferably has a phase separation viscosity lower than the liquid phase viscosity. If it does in this way, it will become possible to phase-divide glass effectively, without making a devitrification crystal | crystallization precipitate at the time of shaping | molding. As a result, a separate heat treatment step for causing phase separation becomes unnecessary, and the production cost of phase separation glass can be reduced. 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 ball pulling method.

  Sixth, the phase-separated glass of the present invention preferably has a Young's modulus of 70 GPa or less. In this way, when the phase separation glass is thinned and the flexible organic EL device is applied, the bending stress of the phase separation glass can be reduced. As a result, the breakage probability of the flexible organic EL device can be reduced.

  Seventh, the phase separation glass of the present invention preferably has a refractive index nd of 1.55 or less. In this way, the amount of expensive heavy metal element added can be reduced. As a result, the batch cost of the phase separation glass can be reduced. Here, “refractive index nd” refers to the value of the d-line measured with a refractive index measuring instrument (for example, a refractive index measuring instrument KPR-2000 manufactured by Shimadzu Corporation). As a measurement example, a rectangular parallelepiped sample of 25 mm × 25 mm × about 3 mm is prepared first, and then the temperature range from (annealing point + 30 ° C.) to (strain point−50 ° C.) is cooled by 0.1 ° C./min. After the slow cooling treatment at a speed, the refractive index nd can be measured by a refractive index measuring device while infiltrating an immersion liquid having a matching refractive index nd.

  Eighth, it is preferable that the phase-separated glass of the present invention has a flat plate shape, that is, a glass plate.

  Ninth, the phase separation glass of the present invention is preferably formed by an overflow down draw method.

  Tenth, the phase-separated glass of the present invention is preferably phase-separated during molding.

  Eleventh, the phase separation glass of the present invention is preferably used for organic EL lighting.

  In the phase-separated glass of the present invention, the average particle size of the phase-separated particles of at least one phase is preferably 0.01 to 5 μm, particularly preferably 0.02 to 1 μm. If the average particle size of the phase-separated particles is too small, the light emitted from the organic EL layer is difficult to scatter at the interface between different phases. On the other hand, if the average particle size of the phase-separated particles is too large, the scattering intensity becomes too strong and the total light transmittance may be lowered.

The phase-separated glass of the present invention contains, as a glass composition, by mass%, SiO ₂ 40 to 75%, Al ₂ O ₃ 0.1 to 20%, B ₂ O ₃ 10 to 40%, preferably SiO _{2. 50~70%, Al 2 O 3 5~20} %, B 2 O 3 15~35%, Li 2 O + Na 2 O + K 2 O 0~10%, MgO + CaO 0.1~20%, containing 0 to 20% SrO + BaO To do. 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 40 to 75%. When the content of SiO ₂ is increased, the meltability and moldability tend to be lowered. Therefore, the preferable upper limit range of SiO ₂ is 75% or less, 70% or less, particularly 65% 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, a suitable lower limit range of SiO ₂ is 40% or more, 50% or more, particularly 55% or more.

The content of Al ₂ O ₃ is preferably 0.1 to 20%. Al ₂ O ₃ is a component that increases devitrification resistance and crack resistance, but if its content is too large, the phase balance is likely to decrease, and the balance of the glass composition component is impaired, On the contrary, the devitrification resistance tends to decrease. Therefore, the preferable upper limit range of Al ₂ O ₃ is 20% or less, 15% or less, particularly 10% or less. On the other hand, when the content of Al ₂ O ₃ is too small, devitrification resistance, crack resistance tends to decrease. Therefore, a preferable lower limit range is 0.1% or more, 1% or more, 3% or more, 4% or more, particularly 5% or more.

The content of B ₂ O ₃ is preferably 10 to 40%. B ₂ O ₃ is a component that enhances phase separation and crack resistance, but if its content is too large, devitrification resistance tends to decrease. Therefore, the preferable upper limit range of B ₂ O ₃ is 40% or less, 30% or less, particularly 25% or less, and the preferable lower limit range is 10% or more, 15% or more, particularly 20% or more.

The mass ratio SiO ₂ / (Al ₂ O ₃ + B ₂ O ₃ ) is preferably 3 or less, 2.5 or less, 2 or less, particularly 1.8 or less, from the viewpoint of improving the phase separation. “SiO ₂ / (Al ₂ O ₃ + B ₂ O ₃ )” is a value obtained by dividing the content of SiO _{2 by} the total amount of Al ₂ O ₃ and B ₂ O ₃ .

Li ₂ O, Na ₂ O, and K ₂ O are components that enhance phase separation. However, if the content of these components 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 suitable upper limit range of Li ₂ O + Na ₂ O + K ₂ O is 10% or less, 5% or less, less than 1%, particularly 0.5% or less, and each of Li ₂ O, Na ₂ O and K ₂ O A suitable upper limit range is also 10% or less, 5% or less, less than 1%, particularly 0.5% or less.

  MgO and CaO are components that increase crack resistance, refractive index, Young's modulus, and strain point, and components that lower high-temperature viscosity. However, if these components are contained in large amounts, the liquidus temperature increases. There is a possibility that the devitrification resistance is lowered or the density becomes too high. Therefore, a preferable upper limit range of MgO + CaO is 20% or less, 10% or less, 7% or less, particularly 5% or less, and a preferable lower limit range is 0.1% or more, 0.5% or more, 1% or more, 2 % Or more, particularly 3% or more. Further, the preferable upper limit range of MgO is 20% or less, 10% or less, 5% or less, particularly 2% or less, and the preferable lower limit range is 0.1% or more, 0.5% or more, particularly 1% or more. is there. Furthermore, the preferable upper limit range of CaO is 20% or less, 15% or less, 10% or less, 9% or less, 8% or less, particularly 7% or less, and the preferable lower limit range is 0.1% or more, 1% or more. 2% or more, particularly 3% or more.

  SrO and BaO are components that increase the resistance to devitrification and the refractive index. However, if these components are contained in a large amount, the crack resistance tends to decrease and the density tends to increase. Therefore, the preferable upper limit range of SrO + BaO is 20% or less, 15% or less, 10% or less, 7% or less, 5% or less, 3% or less, particularly 1% or less. The preferable upper limit ranges of SrO and BaO. Is 20% or less, 15% or less, 10% or less, 7% or less, 5% or less, 3% or less, particularly 1% or less.

The mass ratio (Al ₂ O ₃ + B ₂ O ₃ + MgO + CaO) / (SrO + BaO) is 10 or more, 20 or more, 30 or more, 40 or more, particularly 50 or more from the viewpoint of increasing crack resistance. Here, “(Al ₂ O ₃ + B ₂ O ₃ + MgO + CaO) / (SrO + BaO)” is a value obtained by dividing the total amount of Al ₂ O ₃ , B ₂ O ₃ , MgO and CaO by the total amount of SrO and BaO. Point to.

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

  ZnO is preferably 0 to 20%. If the ZnO content increases, the density tends to increase, and if the ZnO content is too large, the devitrification resistance tends to decrease. Therefore, a suitable upper limit range of ZnO is 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, particularly less than 1%.

TiO ₂ is preferably 0 to 20%. When the content of TiO ₂ increases, the density tends to increase, and when the content of TiO ₂ is too large, the devitrification resistance tends to decrease. Therefore, the preferable upper limit range of TiO ₂ is 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, particularly less than 1%.

ZrO ₂ is preferably 0 to 20%. When the content of ZrO ₂ increases, the density tends to increase, and when the content of ZrO ₂ is too large, the devitrification resistance tends to decrease. Therefore, a suitable upper limit range of ZrO ₂ is 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, particularly less than 1%.

P ₂ O ₅ is a component that improves phase separation, and its content is preferably 0 to 10%. However, when the content of P ₂ O ₅ is increased, the devitrification resistance is likely to be lowered. Therefore, a preferable upper limit range of P ₂ O ₅ is 10% or less, 7% or less, 4% or less, 3% or less, particularly 2% or less, and a preferable lower limit range is 0.001% or more and 0.01%. Above, especially 0.1% or more.

The total content of rare metal oxides is preferably 0 to 10%. Rare metal oxide is a component that increases the refractive index, but as the content of these components increases, the density and thermal expansion coefficient tend to increase, and devitrification resistance decreases, ensuring high liquid phase viscosity. It becomes difficult to do. Furthermore, the raw material cost rises and the production cost of the phase separation glass is likely to rise. Therefore, a preferable upper limit range of the rare metal oxide is 10% or less, 5% or less, 3% or less, 1% or less, 0.5% or less, particularly 0.1% or less. 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 and Ta ₂ O _5. Point to.

As a fining agent, one 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 combined in terms of the following oxides. It can be introduced in an amount of 0 to 3%. 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.

SnO ₂ is a component having a good clarification action in a high temperature region and a component that lowers the high temperature viscosity. The content of SnO ₂ is preferably 0 to 1%, 0.01 to 0.5%, 0.05 to 0.3, particularly 0.1 to 0.3%. When the content of SnO ₂ is too large, the devitrification crystal SnO ₂ is likely to precipitate.

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 3%. 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 3% or less, 2% or less, 1% or less, particularly 0.1% or less. When CeO ₂ is introduced, the preferable lower limit range of CeO ₂ is 0.001%. Above, especially 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 PbO content is preferably 0.5% or less, particularly preferably less than 0.1%.

  In addition to the above components, other components may be introduced in a total amount of preferably 10% (desirably 5%, particularly 1%).

  The phase-separated glass of the present invention preferably has the following characteristics.

The phase separation glass of the present invention has a phase separation temperature higher than the liquid phase temperature. If it does in this way, it will become possible to phase-divide glass, without devitrifying crystal | crystallization precipitating at the time of shaping | molding by control of shaping | molding conditions and slow cooling conditions. As a result, a separate heat treatment step for causing phase separation becomes unnecessary, and the production cost of phase separation glass can be reduced. The phase separation temperature is preferably 900 ° C. or higher, 1000 ° C. or higher, particularly 1100 ° C. or higher. Further, the phase separation viscosity is preferably 10 ^7.0 dPa · s or less, 10 ^6.0 dPa · s or less, and particularly 10 ^5.0 dPa · s or less. If it does in this way, it will become possible to phase-divide glass effectively. As a result, a separate heat treatment step for causing phase separation becomes unnecessary, and the production cost of phase separation glass can be reduced. In the phase-separated glass of the present invention, the glass is preferably phase-separated in the forming step and / or the slow cooling step, but the glass may be phase-separated other than these steps, for example, in the melting step.

The liquid phase viscosity is 10 ^3.5 dPa · s or more, 10 ^4.0 dPa · s or more, 10 ^4.5 dPa · s or more, 10 ^5.0 dPa · s or more, 10 ^5.5 dPa · s or more, In particular, it is 10 ^6.0 dPa · s or more. The liquidus temperature is preferably 1200 ° C. or lower, 1150 ° C. or lower, 1100 ° C. or lower, particularly 1050 ° C. or lower. If it does in this way, it will become difficult to devitrify glass at the time of fabrication. Furthermore, it becomes easy to form a glass plate by an overflow down draw method, a float method or the like.

  The crack resistance is preferably 200 gf or more, 500 gf or more, 700 gf or more, 900 gf or more, 1200 gf or more, particularly 1500 gf or more. When the crack resistance is low, the phase separation glass is easily broken in the manufacturing process of the organic EL device, and the yield of the organic EL device is likely to be reduced.

The thermal expansion coefficient at 30 to 380 ° C. is preferably 10 × 10 ⁻⁷ / ° C. to 100 × 10 ⁻⁷ / ° C., 20 × 10 ⁻⁷ / ° C. to 60 × 10 ⁻⁷ / ° C., 22 × 10 ⁻⁷ / The temperature is from 50 ° C. to 50 × 10 ⁻⁷ / ° C., particularly from 25 × 10 ⁻⁷ / ° C. to 40 × 10 ⁻⁷ / ° C. In recent years, in an organic EL device, there is a case where flexibility is required for a glass plate from the viewpoint of enhancing design elements. In order to increase flexibility, it is necessary to reduce the thickness of the glass plate. In this case, if the thermal expansion coefficients of the glass plate and the transparent conductive film such as ITO or FTO are mismatched, the glass plate warps. It becomes easy. Therefore, if the thermal expansion coefficient at 30 to 380 ° C. is in the above range, such a situation can be easily prevented. In addition, "the thermal expansion coefficient in 30-380 degreeC" points out the average value measured with the dilatometer.

The density is preferably 3.0 g / cm ³ or less, 2.6 g / cm ³ or less, and particularly 2.4 g / cm ³ or less. If it does in this way, an organic EL device can be reduced in weight.

  The strain point is preferably 450 ° C. or higher, 500 ° C. or higher, 550 ° C. or higher, particularly 600 ° 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, if the strain point is in the above range, both transparency of the transparent conductive film and low electrical resistance can be achieved. Furthermore, in the manufacturing process of the organic device, the glass plate is less likely to heat shrink due to heat treatment.

  The Young's modulus is preferably 70 GPa or less, 65 GPa or less, 60 GPa or less, 55 GPa or less, particularly 50 GPa or less. When the Young's modulus is reduced, the stress generated per a certain amount of deformation can be reduced. Further, when an object dropped from an altitude collides with the glass, the glass is easily elastically deformed, so that the impact of the drop is easily mitigated. Moreover, when shape | molding to thin plate glass, it becomes possible to wind in roll shape with a small curvature radius, so that Young's modulus is low.

  The refractive index nd is preferably 1.55 or less. In this way, the amount of expensive heavy metal element added can be reduced. As a result, the batch cost of the phase separation glass can be reduced. On the other hand, if the refractive index nd is too high, the reflectance at the interface between the phase separation glass and the air becomes high, and it becomes difficult to extract light to the outside. On the other hand, the refractive index nd is preferably 1.45 or more. When the refractive index nd is too low, the reflectance at the interface between the phase separation glass and the transparent conductive film becomes high, and it becomes difficult to extract light to the outside.

  The thickness (in the case of a glass plate) is preferably 1.5 mm or less, 1.3 mm or less, 1.1 mm or less, 0.8 mm or less, 0.7 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 thickness, the higher the flexibility and the easier it is to improve the design of organic EL lighting. However, when the thickness is extremely small, the phase-separated glass tends to break. Therefore, the thickness is preferably 10 μm or more, particularly 30 μm or more.

  The phase-separated glass of the present invention is preferably 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 occurs on the surface of the glass plate 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 production cost of the glass plate can be reduced.

  In the case of a glass plate, the surface roughness Ra of at least one surface (particularly an unpolished surface) is preferably 0.01 to 1 μm. When surface roughness Ra is large, when forming a transparent conductive film etc. on the surface, the quality of a transparent conductive film falls 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 phase separation 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. 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 sheet 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.

  The phase-separated glass of the present invention is preferably not subjected to a separate heat treatment step for causing phase separation, and is preferably phase-separated in the molding step or phase-separated in the slow 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 steps of glass will decrease and the production cost of glass can be reduced. The phase separation phenomenon can be controlled by the glass composition, molding conditions, slow cooling conditions, and the like.

In the case of a glass plate, the phase-separated glass of the present invention may have at least one surface as 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 uneven surface roughness Ra is preferably 10 mm or more, 20 mm or more, 30 mm or more, particularly 50 mm or more.

  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 15 are shown.

  First, after preparing a glass raw material so that it might become the glass composition in a table | surface, the obtained glass batch was supplied to the glass melting furnace, and it fuse | melted at 1600 degreeC for 24 hours. Next, the obtained molten glass was poured onto a carbon plate to form a flat plate shape, and subjected to a slow cooling treatment from the strain point to room temperature. Here, the obtained glass plate was phase-separated into different phases during molding. Finally, each glass plate was processed as necessary to evaluate various properties.

  The thermal expansion coefficient is an average value measured with a dilatometer in a temperature range of 30 to 380 ° C. In addition, a φ5 mm × 20 mm cylindrical sample (the end surface is R-processed) was used as a measurement sample.

  The density is a value measured by a well-known Archimedes method.

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

  The annealing point and the softening point 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 and 10 ^2.5 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 phase separation temperature passed through 30 mesh (500 μm sieve opening), and the glass powder remaining in 50 mesh (300 μm sieve opening) was placed in a platinum boat and kept in a temperature gradient furnace for 24 hours. Is a temperature measured in The phase separation viscosity is obtained by measuring the viscosity of the glass at the phase separation temperature by a platinum ball pulling method.

  The liquid phase temperature passes 30 mesh (500 μm sieve opening), the glass powder remaining in 50 mesh (300 μm sieve opening) is placed in a platinum boat and kept in a temperature gradient furnace for 24 hours, after which crystals precipitate Measured temperature. The liquid phase viscosity is obtained by measuring the viscosity of glass at the liquid phase temperature by a platinum ball pulling method.

  The Young's modulus is a value measured by a resonance method.

  The crack occurrence rate is a value measured as follows. First, in a constant temperature and humidity chamber maintained at a humidity of 30% and a temperature of 25 ° C., a Vickers indenter set to a predetermined load is driven into the glass surface (optical polishing surface) for 15 seconds, and 15 seconds later, it is generated from the four corners of the indentation. Count the number of cracks (maximum 4 per indentation). In this manner, the indenter was driven 50 times to determine the total number of cracks generated, and then the total number of cracks generated was calculated by the formula (total number of cracks generated / 200) × 100 (%).

  The refractive index nd is the value of the d line measured by a refractive index measuring instrument KPR-2000 manufactured by Shimadzu Corporation. Specifically, first, a rectangular parallelepiped sample of 25 mm × 25 mm × about 3 mm is prepared, and the temperature range from (annealing point + 30 ° C.) to (strain point−50 ° C.) is gradually increased at a cooling rate of 0.1 ° C./min. It is a value measured by infiltrating an immersion liquid having a matching refractive index nd after the cold treatment.

  As can be seen from Tables 1 and 2, Sample No. In 1 to 15, the phase separation temperature was higher than the liquid phase temperature. Sample No. In each of Nos. 1 to 15, since the phase separation temperature was higher than the liquid phase temperature, the accurate liquid phase temperature could not be measured.

Claims (11)

A phase-separated glass that is phase-separated into different phases,
As a glass composition, it contains SiO ₂ 40 to 75%, Al ₂ O ₃ 0.1 to 20%, B ₂ O ₃ 10 to 40% by mass%, and the phase separation temperature is higher than the liquid phase temperature. Characteristic phase-separated glass. As a glass composition, in _{mass%, SiO 2 50~70%, Al} 2 O 3 5~20%, B 2 O 3 15~35%, Li 2 O + Na 2 O + K 2 O 0~10%, MgO + CaO 0.1~ The phase-separated glass according to claim 1, comprising 20% and SrO + BaO 0 to 20%.   The phase separation glass according to claim 1 or 2, wherein the crack resistance is 200 gf or more. Liquid phase viscosity is 10 < ^3.5 > dPa * s or more, The phase separation glass in any one of Claims 1-3 characterized by the above-mentioned.   The phase separation glass according to any one of claims 1 to 4, wherein the phase separation viscosity is lower than the liquid phase viscosity.   The phase-separated glass according to any one of claims 1 to 5, wherein Young's modulus is 70 GPa or less.   Refractive index nd is 1.55 or less, The phase separation glass in any one of Claims 1-6 characterized by the above-mentioned.   The phase-separated glass according to claim 1, which has a flat plate shape.   The phase-separated glass according to any one of claims 1 to 8, which is formed by an overflow downdraw method.   The phase-separated glass according to any one of claims 1 to 9, wherein the phase-separated glass is phase-separated during molding.   The phase separation glass according to claim 1, wherein the phase separation glass is used for organic EL lighting.