JPWO2014021415A1 - Scintillator panel and method for manufacturing scintillator panel - Google Patents

Abstract

An object of the present invention is to provide a scintillator panel that can form a narrow partition wall in a large area with high accuracy, has high luminous efficiency, and realizes clear image quality. The present invention is a scintillator panel having a flat substrate, a partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition, the partition comprising: It is composed of a material mainly composed of low melting point glass containing 2 to 20% by mass of an alkali metal oxide, and a reflection film is formed on the surface of the partition wall and on the substrate where the partition wall is not formed. Provide a scintillator panel.

Description

  The present invention relates to a scintillator panel constituting a radiation detection apparatus used for medical diagnosis apparatuses, non-destructive inspection devices and the like.

  Conventionally, an X-ray image using a film has been widely used in a medical field. However, since an X-ray image using a film is analog image information, in recent years, digital radiation such as computed radiography (CR) and a flat panel radiation detector (FPD) is used. Detection devices have been developed.

  In a flat panel X-ray detector (FPD), a scintillator panel is used to convert radiation into visible light. The scintillator panel includes an X-ray phosphor such as cesium iodide (CsI), and the X-ray phosphor emits visible light in response to the irradiated X-rays, and the light is emitted by a TFT (Thin Film Transistor). X-ray information is converted into digital image information by converting it into an electrical signal using a CCD (charge-coupled device). However, FPD has a problem that the S / N ratio is low. This is because visible light is scattered by the phosphor itself when the X-ray phosphor emits light. In order to reduce the influence of this light scattering, a method of filling a phosphor in a cell partitioned by a partition wall has been proposed (Patent Documents 1 to 4).

  However, as a method for forming such a partition wall, conventionally used methods include a method of etching a silicon wafer, and a screen printing method using a glass paste which is a mixture of a pigment or ceramic powder and a low melting glass powder. For example, a method of forming a partition pattern by baking after pattern printing in multiple layers. In the method of etching a silicon wafer, the size of the scintillator panel that can be formed is limited by the size of the silicon wafer, and a large size such as a 500 mm square cannot be obtained. In order to make a large size, it is necessary to make a plurality of small sizes side by side. However, it is difficult to manufacture accurately, and it is difficult to manufacture a scintillator panel having a large area.

  Further, in the multi-layer screen printing method using glass paste, high-precision processing is difficult due to dimensional changes of the screen printing plate. Further, in order to prevent the collapse pattern of the partition wall pattern during multi-layer screen printing, it is necessary to increase the partition wall pattern strength by setting the partition wall width to a certain value or more. However, when the partition wall width is widened, the space between the partition walls is relatively narrow, the volume that can be filled with the X-ray phosphor is reduced, and the filling amount is not uniform. For this reason, the scintillator panel obtained by this method has the drawbacks that the amount of X-ray phosphor is small, so that light emission is weak and uneven light emission occurs. These are obstacles to clear imaging in low-dose imaging.

Japanese Patent Laid-Open No. 5-60871 JP-A-5-188148 JP 2011-188148 A JP 2011-007552 A

  In order to produce a scintillator panel with high luminous efficiency and clear image quality, barrier rib processing technology that can process large areas with high accuracy and narrow the barrier rib width, and visible light emitted by phosphors The technology that does not leak the outside of the partition wall is necessary.

  It is an object of the present invention to provide a scintillator panel that solves the above-described drawbacks, forms a narrow partition wall with a large area with high accuracy, and has high luminous efficiency and realizes clear image quality.

This object is achieved by any of the following technical means.
(1) A scintillator panel having a flat substrate, a partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition, the partition comprising an alkali It is composed of a material mainly composed of low melting point glass containing 2 to 20% by mass of a metal oxide, and a reflective film is formed on the surface of the partition wall and on the substrate where the partition wall is not formed. The scintillator panel.
(2) The scintillator panel according to (1), wherein a reflective film is not formed at an interface between the partition wall and the substrate.
(3) The scintillator panel according to (1) or (2), wherein a light shielding film is formed between the partition wall and the reflective film.
(4) A height L1 of the partition wall is larger than an interval L2 between adjacent partition walls, and a width L3 of an interface between the partition wall and the substrate is larger than a width L4 of a top portion of the partition wall, The scintillator panel according to any one of (1) to (3).
(5) A method for producing the scintillator panel according to any one of (1) to (4) above, comprising an inorganic powder containing low-melting glass containing 2 to 20% by mass of an alkali metal oxide on a substrate. And a photosensitive paste coating film formed by applying a photosensitive paste containing a photosensitive organic component, an exposure process of exposing the resulting photosensitive paste coating film, and a photosensitive paste coating film after exposure A developing step for dissolving and removing a portion soluble in the developer, and a photosensitive paste coating film pattern after development is heated to a baking temperature of 500 ° C. to 700 ° C. to remove organic components and soften the low melting point glass Sintering to form barrier ribs, forming a reflective film on the surface of the barrier ribs and portions of the substrate where the barrier ribs are not formed, and filling phosphors in cells partitioned by the barrier ribs When, A method for manufacturing a scintillator panel, comprising:

  According to the present invention, a partition wall can be formed with high accuracy in a large area, and the visible light emitted from the phosphor can be efficiently used. Therefore, a scintillator panel for realizing a large-size and clear photographing and its Manufacturing methods can be provided.

It is sectional drawing which represented typically the structure of the radiation detection apparatus containing the scintillator panel of this invention. It is the perspective view which represented typically the structure of the scintillator panel of this invention. It is sectional drawing which represented typically the structure of the scintillator panel of this invention.

  Hereinafter, preferred configurations of the scintillator panel of the present invention and a radiation detection apparatus using the same will be described with reference to the drawings, but the present invention is not limited to these.

  FIG. 1 is a cross-sectional view schematically showing a configuration of a radiation detection apparatus including a scintillator panel of the present invention. FIG. 2 is a perspective view schematically showing the configuration of the scintillator panel of the present invention. The radiation detection apparatus 1 includes a scintillator panel 2, an output substrate 3, and a power supply unit 12. The scintillator panel 2 includes a scintillator layer 7 made of a phosphor, absorbs the energy of incident radiation such as X-rays, and emits electromagnetic waves having a wavelength in the range of 300 to 800 nm, that is, from ultraviolet light centering on visible light. Radiates electromagnetic waves (light) in the range of infrared light.

  The scintillator panel 2 is formed on a flat substrate 4, a grid-like partition wall 6 for partitioning cells formed thereon, a surface of the partition wall 6, and a portion on the substrate 4 where the partition wall is not formed. The reflection film 13 and a scintillator layer 7 made of a phosphor filled in a space formed by partition walls. Further, by further forming the buffer layer 5 between the substrate 4 and the partition wall 6, the partition wall 6 can be stably formed. The light emitted from the scintillator layer 7 is reflected by the reflection film 13. As a result, the light emitted from the scintillator layer 7 can efficiently reach the photoelectric conversion layer 9 on the output substrate 3.

  The output substrate 3 includes a photoelectric conversion layer 9 and an output layer 10 in which pixels including photosensors and TFTs are two-dimensionally formed on a substrate 11. The radiation detection apparatus 1 is obtained by adhering or adhering the light output surface of the scintillator panel 2 and the photoelectric conversion layer 9 of the output substrate 3 via a diaphragm layer 8 made of polyimide resin or the like. When the light emitted from the scintillator layer 7 reaches the photoelectric conversion layer 9, photoelectric conversion is performed in the photoelectric conversion layer 9 and an electric signal is output through the output layer 10. In the scintillator panel of the present invention, each cell is partitioned by a partition wall. Therefore, by matching the pixel size and pitch of the photoelectric conversion elements arranged in a lattice pattern with the cell size and pitch of the scintillator panel, Each pixel of the conversion element can be associated with each cell of the scintillator panel. Even if the light emitted from the scintillator layer 7 is scattered by the phosphor, the scattered light is reflected by the reflective film 13 on the surface of the partition wall, so that the scattered light can be prevented from reaching the adjacent cell. As a result, blurring of the image due to light scattering can be reduced, and high-accuracy shooting is possible.

  As a substrate used for the scintillator panel of the present invention, various kinds of glass, polymer materials, metals, and the like can be used as long as they are materials that have radiation transparency. For example, plate glass made of glass such as quartz, borosilicate glass, chemically tempered glass; ceramic substrate made of ceramic such as sapphire, silicon nitride, silicon carbide; semiconductor such as silicon, germanium, gallium arsenide, gallium phosphide, gallium nitrogen Semiconductor substrate comprising: cellulose acetate film, polyester film, polyethylene terephthalate film, polyamide film, polyimide film, triacetate film, polycarbonate film, carbon fiber reinforced resin sheet and other polymer films (plastic film); aluminum sheet, iron sheet, copper A metal sheet such as a sheet; a metal sheet having a metal oxide coating layer, an amorphous carbon substrate, or the like can be used. Especially, plate glass is preferable at the point of flatness and heat resistance. Furthermore, since the weight reduction is advanced in order to pursue the convenience of carrying a scintillator panel, it is preferable that plate glass is thin plate glass.

  A partition wall is formed on this substrate. The partition walls need to be made of a material mainly composed of a low melting point glass containing 2 to 20% by mass of an alkali metal oxide from the viewpoint of durability, heat resistance and high-definition processing. A material mainly composed of low melting point glass containing 2 to 20% by mass of an alkali metal oxide has an appropriate refractive index and softening temperature, and is suitable for forming a narrow partition wall in a large area with high accuracy. ing. The low melting point glass means a glass having a softening temperature of 700 ° C. or lower. Moreover, when the low melting point glass containing 2 to 20% by mass of the alkali metal oxide is a main component, 50 to 100% by mass of the material constituting the partition walls is low and contains 2 to 20% by mass of the alkali metal oxide. It means melting glass.

  The method for producing a scintillator panel of the present invention comprises a step of applying a photosensitive paste containing an inorganic powder containing a low-melting glass and a photosensitive organic component on a flat substrate to form a photosensitive paste coating film, The exposure process which exposes the obtained photosensitive paste coating film, the development process which dissolves and removes the part soluble in the developer of the photosensitive paste coating film after exposure, and the photosensitive paste coating film pattern after development are 500 to 700. Heating to a baking temperature of ℃ removes organic components and softens and sinters the low-melting glass to form a partition, and a reflective film is formed on the surface of the partition and on the substrate where the partition is not formed. It is preferable to include a step of forming, and a step of filling the phosphor in the cells partitioned by the partition walls.

  In the exposure process, a necessary portion of the photosensitive paste coating film is photocured by exposure, or an unnecessary portion of the photosensitive paste coating film is photodecomposed, so that the dissolution contrast of the photosensitive paste coating film with respect to the developer is increased. Put on. In the development step, the portion of the photosensitive paste coating film after exposure that is soluble in the developer is dissolved and removed by the developer, and a photosensitive paste coating film pattern in which only necessary portions remain is obtained.

  In the baking step, the resulting photosensitive paste coating film pattern is baked at a temperature of 500 to 700 ° C., preferably 500 to 650 ° C., whereby organic components are decomposed and removed, and the low-melting glass is softened and Sintered to form barrier ribs containing low melting glass. In order to completely remove the organic components, the firing temperature is preferably 500 ° C. or higher. In addition, when the firing temperature exceeds 700 ° C., when a general glass substrate is used as the substrate, deformation of the substrate becomes large, and therefore the firing temperature is preferably 700 ° C. or less.

  The method of the present invention can form a partition wall with higher accuracy than the method of baking after laminating and printing glass paste by multilayer screen printing.

  A photosensitive paste is comprised from the organic component which has photosensitivity, and the inorganic powder containing the low melting glass which contains 2-20 mass% of alkali metal oxides. The organic component needs a certain amount to form the photosensitive paste coating film pattern before firing, but if there is too much organic component, the amount of the substance to be removed in the firing process increases and the firing shrinkage ratio is large. Therefore, pattern defects are likely to occur in the firing process. On the other hand, if the organic component is too small, the mixing and dispersibility of the inorganic fine particles in the paste will be reduced, so that not only will defects easily occur during firing, but the applicability of the paste will decrease due to an increase in paste viscosity. Furthermore, the stability of the paste is also adversely affected, which may be undesirable. For this reason, it is preferable that content of the inorganic powder in the photosensitive paste is 30-80 mass%, and it is more preferable that it is 40-70 mass%.

  Moreover, it is preferable that the ratio of the low melting glass which occupies for the whole inorganic powder is 50-100 mass%. If the low melting point glass is less than 50% by mass of the inorganic powder, sintering does not proceed well in the firing step, and the strength of the resulting partition wall is reduced, which is not preferable.

  In the firing step, in order to remove organic components almost completely and to make the obtained partition walls have a certain strength, a glass powder made of a low-melting glass having a softening temperature of 480 ° C. or higher as a low-melting glass to be used Is preferably used. When the softening temperature is less than 480 ° C., the low-melting glass is softened before the organic component is sufficiently removed during firing, and the organic component residue is taken into the glass. In this case, there is a concern that the organic components are gradually released later and the product quality is deteriorated. Moreover, the residue of the organic component taken in into glass becomes a factor of coloring of glass. By using a low-melting glass powder having a softening temperature of 480 ° C. or higher and baking at 500 ° C. or higher, the organic components can be completely removed. As described above, the firing temperature in the firing step needs to be 500 to 700 ° C, and preferably 500 to 650 ° C. Therefore, the softening temperature of the low melting point glass is preferably 480 to 680 ° C, and 480 to 620 ° C. Is more preferable.

  The softening temperature is determined by calculating the endothermic temperature at the endothermic peak from the DTA curve obtained by measuring the sample using a differential thermal analyzer (DTA, “Differential Differential Thermal Balance TG8120” manufactured by Rigaku Corporation). Obtained by extrapolation. Specifically, using a differential thermal analyzer, the temperature is increased from room temperature to 20 ° C./min using alumina powder as a standard sample, and the inorganic powder as a measurement sample is measured to obtain a DTA curve. The softening point Ts obtained by extrapolating the endothermic end temperature at the endothermic peak from the obtained DTA curve by the tangent method is defined as the softening temperature.

  In order to obtain a low melting glass, it is necessary to use a metal oxide selected from the group consisting of lead oxide, bismuth oxide, zinc oxide and alkali metal oxide, which is an effective material for lowering the glass melting point. it can. Especially, it is preferable to adjust the softening temperature of glass using an alkali metal oxide. In general, the alkali metal refers to lithium, sodium, potassium, rubidium and cesium, but the alkali metal oxide used in the present invention is a metal oxide selected from the group consisting of lithium oxide, sodium oxide and potassium oxide. Say things.

In the present invention, the content X (M ₂ O) of the alkali metal oxide in the low-melting glass needs to be in the range of 2 to 20% by mass. If the content of the alkali metal oxide is less than 2% by mass, the softening temperature becomes high, and thus the firing step needs to be performed at a high temperature. For this reason, when a glass substrate is used as the substrate, the substrate is deformed in the baking process, and thus the resulting scintillator panel is likely to be distorted or defects in the partition walls are easily generated. Moreover, when content of an alkali metal oxide exceeds 20 mass%, the viscosity of glass will fall too much in a baking process. Therefore, the shape of the obtained partition wall is likely to be distorted. Moreover, when the porosity of the obtained partition wall becomes too small, the light emission luminance of the obtained scintillator panel is lowered.

  Furthermore, in addition to the alkali metal oxide, it is preferable to add 3 to 10% by mass of zinc oxide in order to adjust the viscosity of the glass at a high temperature. When the content of zinc oxide is less than 3% by mass, the viscosity of the glass at a high temperature tends to increase. When the content of zinc oxide exceeds 10% by mass, the cost of glass tends to increase.

  Furthermore, in addition to the alkali metal oxide and zinc oxide described above, the low melting point glass contains silicon oxide, boron oxide, aluminum oxide, or an alkaline earth metal oxide, etc., thereby stabilizing the low melting point glass. The crystallinity, transparency, refractive index, thermal expansion characteristic, etc. can be controlled. The composition of the low-melting glass is preferably set to the composition range shown below because a low-melting glass having viscosity characteristics suitable for the present invention can be produced.

Alkali metal oxide: 2 to 20% by mass
Zinc oxide: 3 to 10% by mass
Silicon oxide: 20 to 40% by mass
Boron oxide: 25-40 mass%
Aluminum oxide: 10-30% by mass
Alkaline earth metal oxide: 5 to 15% by mass
The alkaline earth metal is one or more metals selected from the group consisting of magnesium, calcium, barium and strontium.

  The particle size of the inorganic particles containing the low melting point glass can be evaluated using a particle size distribution measuring device (“MT3300” manufactured by Nikkiso Co., Ltd.). As a measuring method, an inorganic powder is put into a sample chamber filled with water, and measurement is performed after ultrasonic treatment for 300 seconds.

  The low melting point glass preferably has a 50% volume average particle diameter (D50) of 1.0 to 4.0 μm. When D50 is less than 1.0 μm, the aggregation of particles becomes strong, it becomes difficult to obtain uniform dispersibility, and the flow stability of the paste tends to be low. In such a case, when the paste is applied, the thickness uniformity of the coating film decreases. On the other hand, if D50 exceeds 4.0 μm, the surface unevenness of the obtained sintered body becomes large, and the pattern tends to be crushed in a subsequent process.

  The photosensitive paste may contain, as a filler, high melting point glass that does not soften at 700 ° C. or ceramic particles such as silicon oxide, aluminum oxide, titanium oxide, or zirconium oxide in addition to the low melting point glass described above. By using the filler together with the low melting point glass, there are effects of controlling the firing shrinkage rate of the paste composition and maintaining the shape of the partition wall to be formed. However, when the proportion of the filler in the entire inorganic powder exceeds 50% by mass, sintering of the low-melting glass is hindered, and problems such as a decrease in the strength of the partition walls are not preferable. The filler preferably has an average particle diameter of 0.5 to 4.0 μm for the same reason as the low melting point glass.

  In the photosensitive paste, the average refractive index n1 of the low-melting glass and the average refractive index n2 of the organic component preferably satisfy −0.1 <n1-n2 <0.1, and −0.01 ≦ n1-n2 ≦ It is more preferable to satisfy 0.01, and it is more preferable to satisfy −0.005 ≦ n1−n2 ≦ 0.005. By satisfying this condition, light scattering at the interface between the low-melting glass and the organic component is suppressed in the exposure process, and a highly accurate pattern can be formed. By adjusting the compounding ratio of the oxide constituting the low-melting glass, a low-melting glass having both preferable thermal characteristics and a preferable average refractive index can be obtained.

  The refractive index of the low melting point glass can be measured by the Becke line detection method. The refractive index (ng) at a wavelength of 436 nm (g line) at 25 ° C. was defined as the refractive index of the low melting point glass in the present invention. Moreover, the average refractive index of an organic component can be calculated | required by measuring the coating film which consists of an organic component by ellipsometry. The refractive index at a wavelength of 436 nm (g line) at 25 ° C. was defined as the average refractive index of the organic component.

  The photosensitive paste can be patterned by the photosensitive paste method as described above by including a photosensitive organic component as an organic component. The reactivity can be controlled by using a photosensitive monomer, photosensitive oligomer, photosensitive polymer, photopolymerization initiator, or the like as the photosensitive organic component. Here, the photosensitivity in the photosensitive monomer, photosensitive oligomer and photosensitive polymer means that when the paste is irradiated with actinic rays, the photosensitive monomer, photosensitive oligomer or photosensitive polymer is photocrosslinked, photopolymerized. It means that the chemical structure is changed by causing the reaction.

  The photosensitive monomer is a compound having an active carbon-carbon double bond, and examples thereof include monofunctional compounds and polyfunctional compounds having a vinyl group, acryloyl group, methacryloyl group or acrylamide group as a functional group. In particular, a compound selected from the group consisting of a polyfunctional acrylate compound and a polyfunctional methacrylate compound containing 10 to 80% by mass in an organic component increases the crosslink density at the time of curing by photoreaction, thereby improving the pattern formability. It is preferable in terms of improvement. Since various types of compounds have been developed as the polyfunctional acrylate compound and the polyfunctional methacrylate compound, it is possible to appropriately select them from the viewpoint of reactivity, refractive index, and the like.

  As the photosensitive oligomer or photosensitive polymer, an oligomer or polymer having an active carbon-carbon unsaturated double bond is preferably used. Photosensitive oligomers or photosensitive polymers include, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid or their anhydrides and other carboxyl group-containing monomers and methacrylic acid esters, acrylic acid. It can be obtained by copolymerizing monomers such as ester, styrene, acrylonitrile, vinyl acetate or 2-hydroxyacrylate. As a method for introducing an active carbon-carbon unsaturated double bond into an oligomer or polymer, an ethylenic group having a glycidyl group or an isocyanate group with respect to a mercapto group, amino group, hydroxyl group or carboxyl group in the oligomer or polymer. For example, a method in which a saturated compound, a carboxylic acid such as acrylic acid chloride, methacrylic acid chloride or allyl chloride, or maleic acid is reacted can be used.

  By using a monomer or oligomer having a urethane bond as the photosensitive monomer or photosensitive oligomer, a photosensitive paste that is less prone to pattern defects in the baking process can be obtained. In the present invention, by using low-melting glass as the glass, rapid shrinkage is unlikely to occur during the process of sintering the glass in the latter stage of the firing process. This can prevent the partition wall from being lost in the firing step. In addition, when a compound having a urethane structure is used as the organic component, stress relaxation occurs in the process of decomposing and distilling off the organic component at the initial stage of the firing process, and it is possible to suppress partition wall defects in a wide temperature range. it can.

  A photopolymerization initiator is a compound that generates radicals upon irradiation with an active light source. Specific examples include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamino) benzophenone, 4,4-bis (diethylamino) benzophenone, 4,4-dichlorobenzophenone, 4-benzoyl-4-methyl. Diphenyl ketone, dibenzyl ketone, fluorenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone Benzyl, benzylmethoxyethyl acetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butylanthraquinone, anthrone, benzanthrone, di Nzosberon, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis (p-azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 1-phenyl-1,2- Butadion-2- (O-methoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2- (O-ethoxycarbonyl) oxime, 1,3-diphenylpropanetrione-2- (O-ethoxycarbonyl) oxime 1-phenyl-3-ethoxypropanetrione-2- (O-benzoyl) oxime, Michler's ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2 -Dimethylamino-1- (4-morpholinophenyl) butano -1, Naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, benzthiazole disulfide, triphenylformine, benzoin peroxide and eosin, methylene blue and other photoreductive dyes and ascorbic acid, triethanolamine, etc. A combination of reducing agents is exemplified. Moreover, you may use these in combination of 2 or more types.

  The photosensitive paste can contain a copolymer having a carboxyl group as a binder. Copolymers having a carboxyl group include, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid or their anhydrides and other carboxyl group-containing monomers and methacrylic acid esters, acrylic acid. Other monomers such as ester, styrene, acrylonitrile, vinyl acetate or 2-hydroxy acrylate are selected and copolymerized using an initiator such as azobisisobutyronitrile. As the copolymer having a carboxyl group, a copolymer having acrylic acid ester or methacrylic acid ester and acrylic acid or methacrylic acid as a copolymerization component is preferably used since the thermal decomposition temperature at the time of firing is low.

  The photosensitive paste becomes a paste excellent in solubility in an aqueous alkaline solution by containing a copolymer having a carboxyl group. The acid value of the copolymer having a carboxyl group is preferably 50 to 150 mgKOH / g. By setting the acid value to 150 mgKOH / g or less, the development allowable range can be widened. Moreover, the solubility with respect to the developing solution of an unexposed part does not fall because an acid value shall be 50 mgKOH / g or more. Therefore, it is not necessary to increase the concentration of the developing solution, and it is possible to prevent peeling of the exposed portion and obtain a high-definition pattern. Furthermore, it is also preferable that the copolymer having a carboxyl group has an ethylenically unsaturated group in the side chain. Examples of the ethylenically unsaturated group include an acryl group, a methacryl group, a vinyl group, and an allyl group.

  The photosensitive paste is prepared by adding an organic solvent and a binder to a photosensitive organic component comprising a low-melting glass and a photosensitive monomer, photosensitive oligomer, photosensitive polymer, photopolymerization initiator, etc. After preparing the composition, it is mixed and dispersed homogeneously with three rollers or a kneader.

  The viscosity of the photosensitive paste can be appropriately adjusted according to the addition ratio of inorganic powder, thickener, organic solvent, polymerization inhibitor, plasticizer, anti-settling agent, etc., but the range is preferably 2 to 200 Pa · s. . For example, when the photosensitive paste is applied to the substrate by spin coating, a viscosity of 2 to 5 Pa · s is preferable. In order to apply the photosensitive paste to the substrate by a screen printing method and obtain a film thickness of 10 to 20 μm by a single application, a viscosity of 50 to 200 Pa · s is preferable. When using a blade coater method or a die coater method, a viscosity of 10 to 50 Pa · s is preferable.

  A partition wall can be formed by applying the photosensitive paste thus obtained onto a substrate, forming a desired pattern by a photolithography method, and further baking. Although an example in which the barrier rib is manufactured using the photosensitive paste by a photolithography method will be described, the present invention is not limited to this.

  A photosensitive paste coating film is formed by coating a photosensitive paste on the entire surface or a part of the substrate. As a coating method, methods such as a screen printing method, a bar coater, a roll coater, a die coater, or a blade coater can be used. The coating thickness can be adjusted by selecting the number of coatings, screen mesh, paste viscosity, and the like.

Subsequently, an exposure process is performed. A method of exposing through a photomask is common, as is done in normal photolithography. In this case, the photosensitive paste coating film is exposed through a photomask having a predetermined opening corresponding to the partition pattern to be obtained. Moreover, you may use the method of drawing directly with a laser beam etc., without using a photomask. A proximity exposure machine or the like can be used as the exposure apparatus. Moreover, when performing exposure of a large area, after apply | coating the photosensitive paste on a board | substrate and exposing while conveying, a large area can be exposed with the exposure machine of a small exposure area. Examples of the actinic rays used for exposure include near infrared rays, visible rays, and ultraviolet rays. Among these, ultraviolet rays are preferable, and as the light source, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a halogen lamp, or a germicidal lamp can be used, and an ultrahigh-pressure mercury lamp is preferable. Although exposure conditions vary depending on the coating thickness, exposure is usually performed for 0.01 to 30 minutes using an ultrahigh pressure mercury lamp having an output of 1 to 100 mW / cm ² .

  After exposure, development is performed using the difference in solubility in the developer between the exposed and unexposed portions of the photosensitive paste coating film, and the soluble portion of the photosensitive paste coating film soluble in the developer is dissolved and removed. A lattice-shaped photosensitive paste coating film pattern is obtained. Development is performed by dipping, spraying or brushing. A solvent that can dissolve the organic components in the paste can be used for the developer. The developer is preferably composed mainly of water. When a compound having an acidic group such as a carboxyl group is present in the paste, development can be performed with an alkaline aqueous solution. As the alkaline aqueous solution, an inorganic alkaline aqueous solution such as sodium hydroxide, sodium carbonate or calcium hydroxide can be used. However, it is preferable to use an organic alkaline aqueous solution because an alkaline component can be easily removed during firing. Examples of the organic alkali include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine and diethanolamine. The concentration of the alkaline aqueous solution is preferably 0.05 to 5% by mass, and more preferably 0.1 to 1% by mass. If the alkali concentration is too low, the soluble portion is not removed, and if the alkali concentration is too high, the pattern portion may be peeled off and the insoluble portion may be corroded. The development temperature during development is preferably 20 to 50 ° C. in terms of process control.

  Next, a firing process is performed in a firing furnace. The atmosphere and temperature of the firing process vary depending on the type of the photosensitive paste and the substrate, but firing is performed in air, nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace or a belt-type continuous firing furnace can be used. Firing is preferably carried out by holding at a temperature of 500 to 700 ° C. for 10 to 60 minutes. The firing temperature is more preferably 500 to 650 ° C. Through the above steps, organic components are removed from the lattice-shaped photosensitive paste coating film pattern, and the low-melting glass contained in the coating film pattern is softened and sintered, so that the lattice is substantially made of an inorganic substance on the substrate. A partition member in which a partition wall is formed is obtained.

  Next, a metallic reflective film is formed on the surface of the partition formed as described above and on the portion of the substrate where the partition is not formed.

In the present invention, in order to prevent light leakage from the barrier ribs, it is necessary that a reflective film is formed on the surface of the barrier ribs and on the portion of the substrate where the barrier ribs are not formed. The material of the reflective film is not particularly limited, and a material that transmits X-rays and reflects visible light that is an electromagnetic wave of 300 to 800 nm emitted from the phosphor can be used. Among them, metals such as Ag, Au, Al, Ni, and Ti that are less deteriorated or metal oxides such as TiO ₂ , ZrO ₂ , Al ₂ O ₃ , and ZnO are preferable. In the present invention, the surface of the partition means the surface of the partition excluding the portion where the partition and the substrate are in contact, that is, the top of the partition and the side of the partition.

  The preferred thickness of the reflective film varies depending on the material used. For example, in the case of a metal film, a range of 0.005 μm to 20 μm is preferable, and a range of 0.01 to 3 μm is more preferable. When the thickness of the reflective film is 0.005 μm or more, the reflectance is increased. On the other hand, the thicker the reflective film, the smaller the cell volume and the smaller the amount of phosphor that can be filled in the cell. Therefore, it is preferable that the thickness of the reflective film is as thin as possible within a range where the reflectance is not lowered.

  By forming the reflective film after the partition walls are formed, a reflective film of the same material can be formed at the same time on the surface of the partition walls and the portion on the substrate where the partition walls are not formed. As a result, it is possible to form a material having a reflectance similarly on the side wall of the partition wall and the surface on the substrate, and the visible light emitted from the phosphor can be more efficiently and uniformly guided to the sensor side. Moreover, it is preferable not to form a reflective film on the surface of the substrate before the barrier ribs are formed. That is, it is preferable that a reflective film is not formed at the interface where the partition wall and the substrate are in contact with each other. This is because when the reflective film is formed on the substrate before the partition walls are formed, the exposure light is scattered by the reflective film in the exposure process for forming the partition walls, and a high-definition pattern cannot be formed.

  The method for forming the reflective film is not particularly limited, and various film forming methods such as a vacuum film forming method, a plating method, a paste coating method, and a spraying method by spraying can be used. Among these, the vacuum film forming method is preferable because a uniform reflective film can be formed at a relatively low temperature. Examples of the vacuum film forming method include vapor deposition, sputtering, ion plating, CVD, and laser ablation. Sputtering is more preferable because a uniform film can be formed on the side wall of the partition wall.

  The plating method is preferable because the reflective film can be stably formed on a large area at a low cost. In the plating method, first, a base metal film is formed by electroless plating on the entire surface of the surface of the partition wall and the portion where the partition wall is not formed on the substrate, and then a high reflectance is obtained by electrolytic plating on the metal film. The method of forming the metal film is preferable. Ni, Cu, Sn, Au, etc. are mentioned as a metal of the base layer formed by electroless plating. Ni is particularly preferable. Moreover, as a metal film formed by electrolytic plating, Ag, Al, etc. are preferable.

  Note that when the reflective film is formed, if the temperature higher than the firing temperature in the firing step for forming the partition wall is applied, the partition wall is deformed. Therefore, the temperature at the time of forming the reflective film is lower than the temperature at the time of partition wall formation. It is preferable.

FIG. 3 is a cross-sectional view schematically showing the configuration of the scintillator panel of the present invention.
100-3000 micrometers is preferable and, as for the height L1 of the partition 6 after reflection film formation, 160-500 micrometers is more preferable. When L1 exceeds 3000 μm, the workability when forming the partition walls is lowered. On the other hand, when L1 is less than 100 μm, the amount of phosphor that can be filled is reduced, and the light emission luminance of the obtained scintillator panel is lowered.

  The interval L2 between adjacent partitions is preferably 30 to 1000 μm. When L2 is less than 30 μm, workability when forming the partition walls is lowered. Moreover, when L2 is too large, the accuracy of the image of the scintillator panel obtained will become low.

  The height L1 of the partition walls is preferably larger than the interval L2 between the partition walls. This is because by increasing the partition wall, the amount of phosphor filled increases and the light emission luminance improves. According to the method of the present invention, a higher partition can be formed by forming the reflective film after the partition is formed.

  The width (bottom width) L3 of the interface between the partition wall and the substrate is preferably larger than the width L4 of the top portion of the partition wall. This is because, since the reflective film is formed after the partition wall is formed, when L4 is larger than L3, the side wall surface of the partition wall near the top of the partition wall may be behind the top of the partition wall and the reflective film may not be formed.

  The bottom width L3 is preferably 10 to 150 μm, and the top width L4 is preferably 5 to 80 μm. More preferably, L3 is 20 to 150 μm. When L3 is less than 10 μm, defects in the partition walls are likely to occur during firing. On the other hand, when L3 is larger than 150 μm, the amount of phosphor that can be filled in the space partitioned by the partition walls is reduced. Moreover, the intensity | strength of a partition will fall that L4 is less than 5 micrometers. On the other hand, if L4 exceeds 80 μm, the region from which the emitted light of the scintillator layer can be extracted becomes narrow. The aspect ratio (L1 / L3) of the partition wall height L1 to the bottom width L3 is preferably 1.0 to 25.0. The larger the aspect ratio (L1 / L3), the wider the space per pixel divided by the partition, and the more phosphor can be filled.

  The aspect ratio (L1 / L2) of the partition wall height L1 with respect to the partition wall interval L2 is preferably 0.5 to 3.5. The higher the aspect ratio (L1 / L2), the higher the partition is, and the more fine phosphors can be filled in the space per pixel. The aspect ratio (L1 / L2) is more preferably 1.0 to 3.5.

  The partition wall height L1 and the partition wall spacing L2 can be measured by exposing a partition wall cross section perpendicular to the substrate and observing the cross section with a scanning electron microscope (S2400, manufactured by Hitachi, Ltd.). The width of the partition wall at the contact portion between the partition wall and the substrate is L3. When there is a buffer layer between the partition wall and the substrate, the width of the partition wall at the contact portion between the partition wall and the buffer layer is L3. The width of the topmost part of the partition is L4.

  Next, a scintillator panel can be completed by filling the cells partitioned by the barrier ribs with a phosphor. Here, the cell refers to a space partitioned by lattice-shaped partition walls. The phosphor filled in the cell is called a scintillator layer.

Various known phosphor materials can be used as the phosphor. In particular, the conversion to visible light is high from the _{X-ray, CsI, Gd 2 O 2 S} , Lu 2 O 2 S, Y 2 O 2 S, LaCl 3, LaBr 3, LaI 3, CeBr 3, CeI 3, LuSiO 5 Alternatively, Ba (Br, F, Z) or the like is used, but is not limited. In addition, various activators may be added to increase luminous efficiency. For example, in the case of CsI, sodium iodide (NaI) mixed at an arbitrary molar ratio, indium (In), thallium (Tl), lithium (Li), potassium (K), rubidium (Rb) or sodium (Na It is preferable to contain an activator such as A thallium compound such as thallium bromide (TlBr), thallium chloride (TlCl), or thallium fluoride (TlF, TlF ₃ ) can also be used as an activator.

  The scintillator layer is formed by, for example, a method of depositing crystalline CsI (in this case, a thallium compound such as thallium bromide can be co-deposited) by vacuum deposition, or phosphor slurry dispersed in water on a substrate. Application method, phosphor powder, organic binder such as ethyl cellulose or acrylic resin, and phosphor paste prepared by mixing with organic solvent such as terpineol or γ-butyrolactone may be applied by screen printing or dispenser. it can.

  The amount of phosphor filled in the cell partitioned by the partition walls is preferably such that the volume fraction occupied by the phosphor in the cell is 50 to 100%. When the volume fraction occupied by the phosphor is less than 50%, the efficiency of efficiently converting incident X-rays into visible light is lowered. Increasing the conversion efficiency of incident X-rays can be achieved by increasing the aspect ratio (L1 / L2) of the partition wall height to the partition wall pitch, but filling the phosphor with high density in the cell space. Therefore, it is preferable because the conversion efficiency can be further increased.

  In order to improve light reflectivity and prevent light leakage from the partition, it is preferable to form a light shielding film between the partition and the reflective film. The material of the light shielding film is not particularly limited, and a metal film such as chromium, nichrome or tantalum, a metal oxide such as chromium oxide, a resin containing a black pigment such as carbon, or the like can be used. The method for forming the light shielding film is not particularly limited, and a method of applying a pasted material and various vacuum film forming methods can be used.

  The preferred thickness of the light shielding film varies depending on the material used. For example, in the case of a metal film, a range of 0.005 μm to 20 μm is preferable, and a range of 0.01 to 3 μm is more preferable. When the thickness of the light shielding film is 0.005 μm or more, the light shielding property is enhanced. On the other hand, as the thickness of the light-shielding film increases, the cell volume decreases and the amount of phosphor that can be filled in the cell decreases. Therefore, the thickness of the light-shielding film is preferably as thin as possible as long as the light-shielding property is not lowered. .

  Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to this.

(Raw material for photosensitive paste for barrier ribs)
The raw material used for the photosensitive paste of an Example is as follows.
Photosensitive monomer M-1: Trimethylolpropane triacrylate photosensitive monomer M-2: Tetrapropylene glycol dimethacrylate photosensitive polymer: Copolymer comprising a mass ratio of methacrylic acid / methyl methacrylate / styrene = 40/40/30 Of 0.4 equivalent of glycidyl methacrylate with respect to the carboxyl group (weight average molecular weight 43000, acid value 100)
Photopolymerization initiator: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1 (IC369 manufactured by BASF)
Polymerization inhibitor: 1,6-hexanediol-bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionate])
Ultraviolet absorber solution: Sudan IV (manufactured by Tokyo Ohka Kogyo Co., Ltd.) γ-butyrolactone 0.3% by mass solution Binder polymer: Ethyl cellulose (manufactured by Hercules)
Viscosity modifier: Flownon EC121 (Kyoeisha Chemical Co., Ltd.)
Solvent A: γ-butyrolactone.

Low melting glass powder A:
SiO ₂ 27% by mass, B ₂ O ₃ 31% by mass, ZnO 6% by mass, Li ₂ O 7% by mass, MgO 2% by mass, CaO 2% by mass, BaO 2% by mass, Al ₂ O ₃ 23% by mass, refraction. Rate (ng): 1.56, glass softening temperature 588 ° C., coefficient of thermal expansion 70 × 10 ⁻⁷ , average particle size 2.3 μm.

Low melting glass powder B:
SiO ₂ 28% by mass, B ₂ O ₃ 30% by mass, ZnO 6% by mass, Li ₂ O 2% by mass, MgO 3% by mass, CaO 3% by mass, BaO 3% by mass, Al ₂ O ₃ 25% by mass, refraction. Rate (ng): 1.551, softening temperature 649 ° C., thermal expansion coefficient 49 × 10 ⁻⁷ , average particle diameter 2.1 μm.

Low melting glass powder C:
SiO ₂ 30% by mass, B ₂ O ₃ 34% by mass, ZnO 4% by mass, Li ₂ O 1% by mass, MgO 1% by mass, CaO 2% by mass, BaO 3% by mass, Al ₂ O ₃ 26% by mass, refraction. Rate (ng): 1.542, glass softening temperature 721 ° C., thermal expansion coefficient 38 × 10 ⁻⁷ , average particle diameter 2.0 μm.

Low melting glass powder D:
SiO ₂ 22% by mass, B ₂ O ₃ 30% by mass, ZnO 1% by mass, Li ₂ O 8% by mass, Na ₂ O 10% by mass, K ₂ O 6% by mass, MgO 4% by mass, BaO 11% by mass, Al ₂ O ₃ 8% by mass, refractive index (ng): 1.589, glass softening temperature 520 ° C., thermal expansion coefficient 89 × 10 ⁻⁷ , average particle diameter 2.4 μm.

Low melting glass powder E:
SiO ₂ 28% by mass, B ₂ O ₃ 23% by mass, ZnO 4% by mass, Li ₂ O 5% by mass, K ₂ O 15% by mass, MgO 4% by mass, BaO 1% by mass, Al ₂ O ₃ 20% by mass. , Refractive index (ng): 1.563, glass softening temperature 540 ° C., thermal expansion coefficient 86 × 10 ⁻⁷ , average particle diameter 2.2 μm.

High melting point glass powder A:
SiO ₂ 30% by mass, B ₂ O ₃ 31% by mass, ZnO 6% by mass, MgO 2% by mass, CaO 2% by mass, BaO 2% by mass, Al ₂ O ₃ 27% by mass, refractive index (ng): 1. 55, softening temperature 790 ° C., thermal expansion coefficient 32 × 10 ⁻⁷ , average particle diameter 2.3 μm.

(Preparation of partition wall paste)
Using the above materials, partition pastes used in Examples and Comparative Examples were produced by the following method.

  Photosensitive paste A for partition walls: 4 parts by weight of photosensitive monomer M-1, 6 parts by weight of photosensitive monomer M-2, 24 parts by weight of photosensitive polymer, 6 parts by weight of a photopolymerization initiator, 0.2 of polymerization inhibitor Part by mass and 12.8 parts by mass of the ultraviolet absorber solution were dissolved in 38 parts by mass of the solvent A by heating at a temperature of 80 ° C. After cooling the obtained solution, 9 mass parts of viscosity modifiers were added, and the organic solution 1 was produced. The refractive index (ng) of the organic coating film obtained by applying the organic solution 1 to a glass substrate and drying it was 1.555.

  Next, 30 parts by mass of the low-melting glass powder A and 10 parts by mass of the high-melting glass powder A are added to 60 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader, so Paste A was prepared.

  Barrier photosensitive paste B: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 30 parts by mass of the low-melting glass powder B and 10 parts by mass of the high-melting glass powder A are added to 60 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader, so Paste B was prepared.

  Barrier photosensitive paste C: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 30 parts by mass of the low-melting glass powder C and 10 parts by mass of the high-melting glass powder A are added to 60 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader to produce a photosensitive film for the partition wall. Paste C was prepared.

  Barrier photosensitive paste D: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 30 parts by mass of the low-melting glass powder D and 10 parts by mass of the high-melting glass powder A are added to 60 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader to produce a photosensitive film for the partition wall. Paste D was prepared.

  Barrier photosensitive paste E: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 30 parts by mass of the low-melting glass powder E and 10 parts by mass of the high-melting glass powder A are added to 60 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader, and the photosensitive film for the partition wall. Paste E was prepared.

  Screen printing paste A for partition walls: 50 parts by mass of a terpineol solution containing 10% by mass of ethyl cellulose and 50 parts by mass of low-melting glass powder D were mixed to prepare a screen printing paste A for partition walls. The refractive index (ng) of the organic coating film obtained by applying and drying a terpineol solution containing 10% by mass of ethyl cellulose on a glass substrate was 1.49.

(Measurement of emission luminance)
The produced scintillator panel was set in any of PaxScan2520, PaxScan4336, and PaxScan3030 (Varian FPD) to produce a radiation detection apparatus. X-rays having a tube voltage of 80 kVp were irradiated from the substrate side of the scintillator panel, and the amount of light emitted from the phosphor layer was detected by any of PaxScan 2520, PaxScan 4336, and PaxScan 3030.

(Evaluation of image defects)
The produced scintillator panel was set in one of PaxScan 2520, PaxScan 4336, and PaxScan 3030 to produce a radiation detection apparatus. X-rays with a tube voltage of 80 kVp were irradiated from the substrate side of the scintillator panel, and a solid image was taken. This was reproduced as an image by an image reproducing device, and the obtained print image was visually observed to evaluate the presence or absence of image defects, crosstalk and linear noise.

Example 1
The barrier rib photosensitive paste A was applied to a 500 mm × 500 mm glass substrate (OA-10, manufactured by Nippon Electric Glass Co., Ltd.) with a die coater so as to have a dry thickness of 500 μm, and dried. A paste coating film was formed. Next, the photosensitive paste coating film for barrier ribs is applied to an ultra high pressure mercury lamp through a photomask (a chromium mask having a grid-like opening portion having a pitch of 125 μm and a line width of 20 μm) in which openings corresponding to a desired barrier rib pattern are formed. Was exposed at an exposure amount of 700 mJ / cm ² . The exposed photosensitive paste coating film for barrier ribs was developed in a 0.5% aqueous ethanolamine solution, and unexposed portions were removed to form a lattice-shaped photosensitive paste coating film pattern. Further, the photosensitive paste coating film pattern was baked in the air at 585 ° C. for 15 minutes. The partition wall distance L2 was 125 μm, the top width L4 was 20 μm, the bottom width L3 was 30 μm, and the partition wall height L1 was 340 μm. A partition member having a grid-like partition wall having a size of 480 mm was obtained.

  Thereafter, an aluminum film was formed as a reflective film on the partition wall surface and the substrate surface where the partition wall was not formed, using a batch type sputtering apparatus (SV-9045 manufactured by ULVAC). At this time, the thickness of the aluminum film at the top of the partition was 300 nm, the thickness of the aluminum film on the side of the partition was 100 nm, and the thickness of the aluminum film on the substrate surface without the partition was 200 nm.

  After that, gadolinium oxysulfide powder having a particle size of 5 μm is mixed with ethyl cellulose as a phosphor, and then filled into a space partitioned by partition walls, fired at 450 ° C., and a scintillator with a phosphor volume fraction of 90% in the cell. Panel 1 was produced.

  The produced scintillator panel 1 was set in PaxScan 2520 to produce a radiation detection apparatus, and the emission luminance and image defects were evaluated as described above. There was no defect including linear noise, and a good image with a brightness variation of 3.3% was obtained.

(Example 2)
The partition wall photosensitive paste B is applied to a 500 mm × 500 mm glass substrate (OA-10, manufactured by Nippon Electric Glass Co., Ltd.) with a die coater so as to have a dry thickness of 500 μm, dried, and then the partition wall photosensitive resin. A paste coating film was formed. Next, the photosensitive paste coating film for the barrier ribs is applied to the ultra high pressure mercury lamp through a photomask having an opening corresponding to the desired barrier rib pattern (a chromium mask having a grid-like opening portion having a pitch of 125 μm and a line width of 20 μm). It was exposed with an exposure amount of 700 mJ / cm ² . The exposed photosensitive paste coating film for barrier ribs was developed in a 0.5% aqueous ethanolamine solution, and unexposed portions were removed to form a lattice-shaped photosensitive paste coating film pattern. Further, it was fired in air at 620 ° C. for 15 minutes. The partition wall spacing L2 was 125 μm, the top width L4 was 20 μm, the bottom width L3 was 30 μm, the partition wall height L1 was 340 μm, and the lattice shape was 480 mm × 480 mm. A partition member having a partition was obtained.

  Next, a light-shielding film made of low-reflectance chromium oxide was formed on the partition wall surface and the substrate surface where the partition wall was not formed, using the same sputtering apparatus as in Example 1 and using the target as chromium oxide. At this time, the thickness of the light shielding film was 300 nm. Next, as in Example 1, an aluminum film was formed as a reflective film by sputtering, and in the same manner as in Example 1, the phosphor was filled in the space defined by the partition walls to produce a scintillator panel 2.

  The produced scintillator panel 2 was set on PaxScan 2520 to produce a radiation detection apparatus, and the emission luminance and image defects were evaluated as described above. There was no defect including linear noise, and a good image with a luminance variation of 1.9% was obtained. The luminance was 150% of Example 1.

Example 3
The barrier rib photosensitive paste E is applied to a 500 mm × 500 mm glass substrate (OA-10 manufactured by Nippon Electric Glass Co., Ltd.) with a die coater so as to have a dry thickness of 500 μm, and dried. A paste coating film was formed. Next, the photosensitive paste coating film for barrier ribs is applied to an ultra high pressure mercury lamp through a photomask (a chromium mask having a grid-like opening portion having a pitch of 125 μm and a line width of 20 μm) in which openings corresponding to a desired barrier rib pattern are formed. Was exposed at an exposure amount of 700 mJ / cm ² . The exposed photosensitive paste coating film for barrier ribs was developed in a 0.5% aqueous ethanolamine solution, and unexposed portions were removed to form a lattice-shaped photosensitive paste coating film pattern. Further, the photosensitive paste coating film pattern was baked in the air at 585 ° C. for 15 minutes. The partition wall spacing L2 was 125 μm, the top width L4 was 20 μm, the bottom width L3 was 30 μm, the partition wall height L1 was 330 μm, and 480 mm × A partition member having a grid-like partition wall having a size of 480 mm was obtained.

  Thereafter, an aluminum film was formed as a reflective film on the partition wall surface and the substrate surface where the partition wall was not formed, using a batch type sputtering apparatus (SV-9045 manufactured by ULVAC). At this time, the thickness of the aluminum film at the top of the partition was 300 nm, the thickness of the aluminum film on the side of the partition was 100 nm, and the thickness of the aluminum film on the substrate surface without the partition was 200 nm.

  After that, gadolinium oxysulfide powder having a particle size of 5 μm is mixed with ethyl cellulose as a phosphor, and then filled into a space partitioned by partition walls, fired at 450 ° C., and a scintillator with a phosphor volume fraction of 90% in the cell. Panel 3 was produced.

The produced scintillator panel 3 was set in PaxScan 2520 to produce a radiation detection apparatus, and the emission luminance and image defects were evaluated as described above. There was no defect including linear noise, and a good image with a brightness variation of 2.7% was obtained (Example 4)
In the same manner as in Example 1, a partition member having a grid-shaped partition wall having a size of 480 mm × 480 mm with a partition wall interval L2 of 125 μm, a top width L4 of 20 μm, a bottom width L3 of 30 μm, a partition wall height L1 of 340 μm. Got.

  Thereafter, a nickel film was formed as an underlayer by electroless nickel plating on the surface of the partition and the substrate surface where the partition was not formed. Thereafter, a silver film was formed as a reflective film on the nickel film by electrolytic silver plating. The thicknesses of the nickel film and the silver film were 500 nm and 1000 nm, respectively.

  After that, gadolinium oxysulfide powder having a particle size of 5 μm is mixed with ethyl cellulose as a phosphor, and then filled into a space partitioned by partition walls, fired at 450 ° C., and a scintillator with a phosphor volume fraction of 90% in the cell. Panel 4 was produced.

The produced scintillator panel 4 was set in PaxScan 2520 to produce a radiation detection apparatus, and the emission luminance and image defects were evaluated as described above. There was no defect including linear noise, and a good image with a brightness variation of 3.2% was obtained (Comparative Example 1).
A partition substrate produced by the same method as in Example 1 was filled with a phosphor by the same method as in Example 1 without forming an aluminum reflective film, and a scintillator panel 3 was produced.

  The produced scintillator panel 3 was set in PaxScan 2520 to produce a radiation detection apparatus, and the emission luminance and image defects were evaluated as described above. Although there were no defects including linear noise, the luminance variation increased to 6.2%, and the luminance decreased to 20% of Example 1.

(Comparative Example 2)
A partition wall pattern was formed in the same manner as in Example 2 except that the partition wall photosensitive paste C was used. The obtained partition wall is a partition wall member having a grid-shaped partition wall having a size of 480 mm × 480 mm with a partition wall interval L2 of 125 μm, a top width L4 of 20 μm, a bottom width L3 of 50 μm, and a partition wall height L1 of 340 μm. It was. However, there were many spots where the partition walls were partially missing due to insufficient progress of sintering of the partition walls, and where the bottom of the partition walls became thicker, in contact with the adjacent partition walls, and where the openings were buried. .

(Comparative Example 3)
A partition wall pattern was formed in the same manner as in Example 1 except that the partition wall photosensitive paste D was used. The obtained partition wall has a partition wall partition L2 of 125 μm, a top width L4 of 40 μm, a bottom width L3 of 80 μm, a partition wall height L1 of 340 μm, and a partition wall member having a size of 480 mm × 480 mm. It was. L3 and L4 increased due to the mismatch of the refractive index of the organic component and glass. In addition, the softening of the partition walls during firing progressed excessively, resulting in many locations where the partition walls were missing, and the partition walls were distorted.

(Comparative Example 4)
The partition wall screen printing paste A was applied to a 500 mm × 500 mm glass substrate (OA-10, manufactured by Nippon Electric Glass Co., Ltd.) with a film thickness of 15 μm by screen printing and dried to form a buffer layer. Thereafter, the partition wall screen printing paste A is screen-printed by using a pattern having a vertical and horizontal pitch of 160 μm, an opening length of 130 μm × 130 μm, a wall width of 35 μm and a size suitable for a predetermined number of pixels. Application and drying at 40 μm were repeated 12 layers. Thereafter, firing was performed in air at 550 ° C. to form a partition wall having a top width L4 of 50 μm, a bottom width L3 of 50 μm, and a partition wall height L1 of 450 μm.

  Thereafter, an aluminum film was formed as a reflective film on the partition wall surface and the substrate surface where the partition wall was not formed, using a batch type sputtering apparatus (SV-9045 manufactured by ULVAC). At this time, the thickness of the aluminum film at the top of the partition wall was 300 nm, and the thickness of the aluminum film on the substrate surface without the partition wall was 200 nm, but the side surface of the partition wall had a place where the aluminum film was formed and a place where it was not formed. Occurred.

  After that, gadolinium oxysulfide powder having a particle diameter of 5 μm is mixed with ethyl cellulose as a phosphor, and then filled into a space defined by partition walls, fired at 450 ° C., and a scintillator panel with a phosphor volume fraction of 50% in the cell. 5 was produced. Partial distortion occurred in the barrier rib pattern, and no further phosphor filling was possible.

  The produced scintillator panel 5 was set in PaxScan 2520 to produce a radiation detection apparatus, and the emission luminance and image defects were evaluated as described above. As a result, 80 pixel defects that do not emit light were scattered in the plane.

  From these results, it can be seen that in the examples according to the present invention, the emission luminance is high, and there is little distortion of the partition wall structure, image unevenness and linear noise, and a good image can be obtained.

DESCRIPTION OF SYMBOLS 1 Radiation detection apparatus 2 Scintillator panel 3 Output board 4 Board | substrate 5 Buffer layer 6 Partition 7 Scintillator layer 8 Separator layer 9 Photoelectric conversion layer 10 Output layer 11 Board | substrate 12 Power supply part 13 Reflective film

  INDUSTRIAL APPLICABILITY The present invention can be usefully used as a scintillator panel that constitutes a radiation detection apparatus used in medical diagnostic apparatuses, nondestructive inspection equipment, and the like.

Claims (5)

A scintillator panel having a flat substrate, a partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition,
The partition is made of a material mainly composed of low melting point glass containing 2 to 20% by mass of an alkali metal oxide,
A scintillator panel, wherein a reflective film is formed on a surface of the partition wall and a portion of the substrate where the partition wall is not formed.   The scintillator panel according to claim 1, wherein a reflective film is not formed at an interface between the partition wall and the substrate.   The scintillator panel according to claim 1, wherein a light shielding film is formed between the partition wall and the reflective film.   The height L1 of the partition wall is larger than an interval L2 between adjacent partition walls, and a width L3 of an interface between the partition wall and the substrate is larger than a width L4 of a top portion of the partition wall. The scintillator panel according to claim 3. A method for producing the scintillator panel according to any one of claims 1 to 4,
Applying a photosensitive paste containing an inorganic powder containing a low-melting glass containing 2 to 20% by mass of an alkali metal oxide and a photosensitive organic component on a substrate to form a photosensitive paste coating film;
An exposure step of exposing the obtained photosensitive paste coating film;
A development step of dissolving and removing a portion soluble in the developer of the photosensitive paste coating film after exposure;
A baking step of heating the photosensitive paste coating film pattern after development to a baking temperature of 500 ° C. to 700 ° C. to remove organic components and softening and sintering the low-melting glass to form partition walls;
Forming a reflective film on the surface of the partition wall and the portion of the substrate where the partition wall is not formed;
Filling the phosphor into the cells partitioned by the barrier ribs;
A method for manufacturing a scintillator panel, comprising:

Images