JP2014106020A - Scintillator panel and method for manufacturing the scintillator panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scintillator panel in which a narrow partition wall is formed in a large area with high accuracy, and which has high light emission luminance and provides sharp images.SOLUTION: Provided is a scintillator panel that comprises: a tabular substrate; a grid-like partition wall provided on the substrate; and a scintillator layer formed of phosphor filled in cells obtained by partition with the partition wall. The partition wall is constructed with a material that is mainly composed of low-melting point glass and contains 0.1-40 mass% of white pigment.

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 emission is converted into an electrical signal by a TFT or CCD. Is converted into digital image information. 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, a method conventionally used as a method for forming such a partition is a method of etching a silicon wafer, or a screen printing method using a glass paste which is a mixture of a pigment or ceramic powder and a low melting glass powder. It was a method of forming a partition pattern by firing after pattern printing using 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.

  In addition, in the multilayer screen printing method using glass paste, high-precision processing is difficult due to changes in the dimensions of the screen printing plate. Further, when performing multi-layer screen printing, in order to increase the strength of the partition wall pattern in order to prevent the collapse defect of the partition wall pattern, a certain partition wall width is required. When the width of the barrier rib pattern is widened, the space between the barrier ribs is relatively narrow, the volume that can be filled with the 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 and the light emission becomes weak and the light emission unevenness occurs. This is an obstacle to clear imaging in low-dose imaging.

  That is, in order to manufacture a scintillator panel that has high luminous efficiency and realizes a clear image quality, a partition wall processing technique that can process a large area with high accuracy and that can narrow the partition wall width is required.

Japanese Patent Laid-Open No. 5-60871 JP-A-5-188148 JP 2011-7552 A JP 2011-21924 A

  It is an object of the present invention to provide a scintillator panel that forms a narrow partition wall in a large area with high accuracy, has high emission luminance, 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 grid-like partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition, The partition wall is a scintillator panel composed of a material mainly composed of low melting point glass and containing 0.1 to 40% by mass of a white pigment.
(2) The scintillator panel according to claim 1, wherein the white pigment is a metal oxide selected from the group consisting of aluminum oxide, zirconium oxide and titanium oxide.
(3) The scintillator panel according to claim 1 or 2, wherein the low-melting glass contains 2 to 20% by mass of an alkali metal oxide.
(4) The scintillator panel according to any one of claims 1 to 3, wherein an average particle diameter of the aggregated particles of the white pigment is 0.3 to 2 µm.
(5) A method of manufacturing a scintillator panel having a flat substrate, a grid-like partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition. A step of applying a photosensitive paste containing a low-melting glass powder, a white pigment and a photosensitive organic component on a substrate to form a photosensitive paste coating film; A step of exposing through a photomask having an opening, a development step of dissolving and removing a portion of the photosensitive paste coating film after exposure that is soluble in the developer, and a photosensitive paste coating film pattern after development of 500 to 700 ° C. A heating step for removing organic components by heating to 0 ° C. and softening and sintering the low-melting glass to form partition walls, and a process for filling phosphors in cells partitioned by the partition walls A method of manufacturing a scintillator panel including

  According to the present invention, a narrow partition wall can be formed in a large area with high accuracy, so that it is possible to provide a scintillator panel and a method for manufacturing the scintillator panel for realizing a large size and clear photographing.

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.

  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 nm to 800 nm, that is, from ultraviolet light centering on visible light. Emits electromagnetic waves (light) in the range of infrared light.

  The scintillator panel 2 is composed of a substrate 4, a grid-like partition wall 6 for partitioning cells formed thereon, and a scintillator layer 7 made of phosphor filled in a space formed by the partition wall. Is done. Further, by further forming the buffer layer 5 between the substrate 1 and the partition wall 6, the partition wall 6 can be stably formed. Further, by increasing the reflectance of the buffer layer 5 with respect to visible light, 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 formed by adhering or bringing the light output surface of the scintillator panel 2 and the photoelectric conversion layer 9 of the output substrate 3 into contact with each other via a diaphragm layer 8 made of polyimide resin or the like. The light emitted from the scintillator layer 7 reaches the photoelectric conversion layer 9, performs photoelectric conversion at the photoelectric conversion layer 9, and outputs the result. In the scintillator panel of the present invention, each cell is partitioned by a partition wall. Therefore, by matching the size and pitch of the pixels of the photoelectric conversion elements arranged in a lattice pattern with the size and pitch of the cells of the scintillator panel, fluorescence Even if light is scattered by the body, 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 phosphorus, 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. Among these, plate glass is desirable in terms of flatness and heat resistance. Furthermore, since the weight reduction of the scintillator panel is promoted from the viewpoint of convenience of carrying the scintillator panel, the thickness of the plate glass is preferably 2.0 mm or less, and more preferably 1.0 mm or less.

  A partition is formed on the substrate, and the partition is preferably made of a glass material from the viewpoint of durability and heat resistance. In the scintillator panel of the present invention, the partition wall is made of a material containing low-melting glass as a main component and 0.1 to 40% by mass of a white pigment. Since the material mainly composed of low melting point glass has an appropriate softening temperature, it is suitable for forming a narrow partition wall in a large area with high accuracy by a photosensitive paste method. In the present invention, the low melting point glass is a glass having a softening temperature of 700 ° C. or lower. The phrase “low melting point glass as a main component” means that 50 to 100% by mass of the material constituting the partition walls is low melting point glass powder. When the low melting point glass is not the main component, the strength of the partition walls is lowered.

  When the partition contains 0.1% by mass or more of the white pigment, the light emission luminance of the scintillator panel is improved. On the other hand, when the white pigment is contained in an amount of 40% by mass or more, the strength of the partition walls is lowered.

  As the white pigment, a metal oxide selected from the group consisting of aluminum oxide, zirconium oxide and titanium oxide is preferable in order to further increase the emission luminance.

  The white pigment is preferably present as aggregated particles in which ultrafine particles having an average particle diameter of 0.005 to 0.08 μm are aggregated in the partition walls. The average particle diameter of the agglomerated particles of the white pigment is preferably 0.3 to 2 μm, and more preferably 0.5 to 1 μm, in order to impart high reflectance to the partition walls. Here, the average particle diameter of the aggregated particles of the white pigment means a diameter when an observation photograph taken with an electron microscope or the like is image-processed and converted into a circle having the same area as the apparent area. More specifically, a sample processed by the ion etching method is enlarged and photographed using a transmission electron microscope (hereinafter referred to as TEM), 50 aggregated particles are selected as samples, and images of the respective photographs are taken. It means the average value of the diameters when the aggregated particles are approximated to a sphere (circle on the image) from the processing.

  In the method for producing a scintillator panel of the present invention, a photosensitive paste containing a low-melting glass powder, a white pigment and a photosensitive organic component is applied on a substrate to form a photosensitive paste coating film, and the resulting photosensitive film is obtained. Exposure step of exposing the photosensitive paste coating film through a photomask having a predetermined opening, a development step of dissolving and removing a portion soluble in the developer of the photosensitive paste coating film after exposure, and a photosensitive paste after development The coating film pattern is heated to a high temperature to remove organic components, and the low melting point glass is softened and sintered to form a partition wall. 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, unnecessary portions of the photosensitive paste coating film after exposure are removed with a 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 preferably baked at a temperature of 500 to 700 ° C., more preferably 500 to 650 ° C., whereby the organic components are decomposed and distilled, and the low melting point. The glass powder is softened and sintered to form partition walls containing low melting glass. In order to completely remove the organic components, the firing temperature is preferably 500 ° C. or higher. Further, when the firing temperature exceeds 700 ° C., when a general glass substrate is used as the substrate, the deformation of the substrate becomes large, and therefore the firing temperature is desirably 700 ° C. or less.

  The photosensitive paste used in the method for manufacturing a scintillator panel of the present invention preferably contains a low-melting glass as a main component and 0.1 to 40% by mass of a white pigment as an inorganic component in the photosensitive paste. The phrase “low melting point glass as a main component” means that 50 to 100% by mass of the inorganic component in the photosensitive paste is a low melting point glass powder. By using such a photosensitive paste, it is possible to form partition walls made of a material mainly composed of low-melting glass and containing 0.1 to 40% by mass of a white pigment.

  The average particle size of the white pigment contained in the photosensitive paste is preferably 0.005 to 0.08 μm. Such white pigment fine particles have excellent dispersibility in the photosensitive paste and do not impede transmission of ultraviolet light having a wavelength of 350 to 420 nm, which is typical exposure light. improves. Furthermore, such fine particles of white pigment become aggregated particles having an average particle diameter of 0.3 to 2 μm through the baking step and the development step, and are present in the partition walls. The average particle size of the white pigment fine particles can be calculated in the same manner as the average particle size of the aggregated particles.

  The manufacturing method of the scintillator panel of the present invention can be processed with higher accuracy than the processing method of baking after the glass paste is laminated and printed by multilayer screen printing.

  The photosensitive paste used in the present invention is composed of an organic component containing a photosensitive organic component, an inorganic powder containing a low-melting glass powder and a white pigment. 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. Therefore, the content of the inorganic powder in the photosensitive paste is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass. Moreover, it is preferable that a low melting glass powder is 50-100 mass% with respect to the whole inorganic powder.

  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 composed of a low-melting glass having a softening temperature of 480 ° C. or higher is used as the low-melting glass powder to be used. It is preferable to use a powder. 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. In addition, organic component residues incorporated in the glass cause the coloring of the glass. By using a low-melting glass powder having a softening temperature of 480 ° C. or higher and baking at a temperature of 500 ° C. or higher, the organic components can be completely removed. As described above, the firing temperature in the firing step is preferably 500 to 700 ° C, more preferably 500 to 650 ° C, and thus the softening temperature of the low-melting glass is preferably 480 to 700 ° C, more preferably 480 to 640 ° C, 480-620 degreeC is further 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.

The thermal expansion coefficient of the low-melting glass is preferably 40 to 90 × 10 ⁻⁷ (/ K), more preferably 40 to 65 × 10 ⁻⁷ . When a photosensitive paste coating film containing a low-melting glass is formed on a substrate and baked, if the thermal expansion coefficient is larger than 90 × 10 ⁻⁷ , the panel is greatly warped, so that it can be assembled as a radiation detection device. It becomes difficult. In addition, in a radiation detection apparatus in which panel warpage has occurred, crosstalk of emitted light occurs in the panel surface, and variations in detection sensitivity of emitted light amount occur, making it difficult to detect high-definition images. On the other hand, when the thermal expansion coefficient is smaller than 40 × 10 ⁻⁷ , the softening temperature of the low melting point glass cannot be lowered sufficiently.

  In order to obtain a low-melting glass, a metal oxide selected from lead oxide, bismuth oxide, zinc oxide and alkali metal oxide, which is an effective material for lowering the melting point of the glass, can be used. Among these, it is desirable to adjust the softening temperature of the glass using an alkali metal oxide. In general, alkali metal refers to lithium, sodium, potassium, rubidium, and cesium, but the alkali metal oxide used in the present invention refers to a metal oxide selected from lithium oxide, sodium oxide, and potassium oxide. .

In the present invention, the content X (M ₂ O) of the alkali metal oxide in the low-melting glass is preferably 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 there is more content of an alkali metal oxide than 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 desirable 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 3% by mass or less, the viscosity of the glass at a high temperature is high, and when 10% by mass or more is added, the cost of the glass tends to be high.

  Furthermore, in addition to the above alkali metal oxides and zinc oxide, the low melting glass contains silicon oxide, boron oxide, aluminum oxide, alkaline earth metal oxides, etc. to stabilize the low melting glass. Properties, crystallinity, transparency, refractive index, thermal expansion characteristics, and the like 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
In the present invention, the alkaline earth metal refers to one or more metals selected from magnesium, calcium, barium and strontium.

  The particle size of the low melting point glass powder 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.

  As for the particle diameter of the low melting glass powder, the 50% volume average particle diameter (D50) is preferably in the range 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 fluidity of the paste becomes unstable. In such a case, the thickness uniformity when the paste is applied 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 used in the present invention may contain, as a filler, high melting point glass that does not soften at 700 ° C. or ceramic particles such as silicon oxide, cordierite, mullite, or feldspar in addition to the above-described low melting glass powder and white pigment. Good. By using the filler together with the low melting point glass powder, 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, if the proportion of the filler in the entire inorganic powder exceeds 50% by mass, sintering of the low-melting glass powder is hindered and problems such as a decrease in the strength of the partition walls are not preferable. The filler preferably has a D50 of 0.5 to 4.0 μm for the same reason as the low melting point glass powder. D50 of the filler can be evaluated by the same method as that for the low-melting glass powder.

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

  The refractive index of the low melting glass powder or filler can be measured by the Becke line detection method. The refractive index at a wavelength of 436 nm (g line) at 25 ° C. was defined as the refractive index of the low-melting glass powder or filler in the present invention. The average refractive index of the photosensitive organic component can be determined by measuring the coating film composed of the photosensitive 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 photosensitive organic component.

  The photosensitive paste used in the present invention 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 or photopolymerized. It means that the chemical structure changes due to the reaction.

  As a photosensitive monomer, it is a compound which has an active carbon-carbon double bond, and the monofunctional compound and polyfunctional compound which have a vinyl group, an acryloyl group, a methacryloyl group, and an acrylamide group as a functional group are used preferably. In particular, a compound selected from a polyfunctional acrylate compound and a polyfunctional methacrylate compound in an organic component in an amount of 10 to 80% by mass increases the crosslink density at the time of curing by photoreaction, and improves pattern formation. This is preferable. 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 and photosensitive polymer, oligomers and polymers having an active carbon-carbon double bond are preferably used. Photosensitive oligomers and photosensitive polymers include, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, 3-butenoic acid or carboxyl group-containing monomers such as acid anhydrides and methacrylic acid esters, It can be obtained by copolymerizing monomers such as acrylic ester, styrene, acrylonitrile, vinyl acetate, 2-hydroxyethyl acrylate. 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 is used. 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 structure as the photosensitive monomer or photosensitive oligomer, it is possible to obtain a photosensitive paste that is less prone to pattern loss in the baking step. In the present invention, by using a low-melting glass powder as the glass powder, it is difficult to cause rapid shrinkage in the process of sintering the glass powder in the latter stage of the firing process, thereby suppressing pattern defects. 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 baking process, and pattern defects are less likely to occur. Both of these effects can suppress pattern defects over a wide temperature range.

  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, reduction of naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, benzthiazole disulfide, triphenylphosphine, benzoin peroxide and eosin, methylene blue and ascorbic acid, triethanolamine, etc. Combinations of agents are included. 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. As the copolymer having a carboxyl group, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, 3-butenoic acid or a carboxyl group-containing monomer such as acid anhydride thereof, and methacrylic acid Other monomers such as ester, acrylate ester, styrene, acrylonitrile, vinyl acetate, 2-hydroxyethyl acrylate are selected and copolymerized using an initiator such as azobisisobutyronitrile. As the copolymer having a carboxyl group, a copolymer having an 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 alkaline aqueous 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 acryloyl group, methacryloyl group, vinyl group and allyl group.

  The photosensitive paste is a low melting glass powder, a white pigment, a photosensitive monomer, a photosensitive oligomer, a photosensitive polymer, a photosensitive organic component composed of a photopolymerization initiator and the like, if necessary, an organic solvent and a binder, After preparing various components so as to have a predetermined composition, they are uniformly mixed and dispersed with a three-roller or a kneader.

  The viscosity of the photosensitive paste can be appropriately adjusted depending on the addition ratio of inorganic powder, thickener, organic solvent, polymerization inhibitor, plasticizer, anti-settling agent, etc., but the range is in the range of 2 to 200 Pa · s. The inside is preferable. 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 screen printing and obtain a film thickness of 10 to 40 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, and a blade coater can be used. The coating thickness can be adjusted by selecting the number of coatings, screen mesh and paste viscosity.

Subsequently, an exposure process is performed. A method of exposing through a photomask is common, as is done in normal photolithography. Alternatively, a method of directly drawing with a laser beam or the like without using a photomask may be used. 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. In this case, examples of the actinic rays used include near infrared rays, visible rays, and ultraviolet rays. Among these, ultraviolet rays are most 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. Among these, an ultrahigh pressure mercury lamp is suitable. 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 the exposure, development is performed using the difference in solubility in the developer between the exposed portion and the unexposed portion of the photosensitive paste coating film to obtain a photosensitive paste coating film pattern having a desired lattice shape. 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, calcium hydroxide or the like can be used. However, it is preferable to use an organic alkaline aqueous solution because an alkaline component can be easily removed during firing. Specific 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, 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. Moreover, it is preferable on process control that the developing solution temperature at the time of image development is 20-50 degreeC.

  Next, a firing process is performed in a firing furnace. The atmosphere and temperature of the firing process vary depending on the type of photosensitive paste and 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.

  The height (H) of the partition walls is preferably 100 to 1000 μm, more preferably 160 to 500 μm, and further preferably 250 to 500 μm. If the height of the partition wall exceeds 1000 μm, pattern formation during processing becomes difficult. On the other hand, when the height of the partition walls is lowered, the amount of phosphor that can be filled is reduced, so that the light emission luminance of the obtained scintillator panel is lowered, and clear photographing becomes difficult.

  The pattern shape of the partition is not particularly limited, but a lattice shape or a stripe shape is preferable. When forming a lattice-like pattern, the pitch (P) of the partition walls is preferably 60 to 1000 μm. If the pitch is less than 60 μm, pattern formation during processing becomes difficult. On the other hand, if the pitch is too large, it is difficult to perform high-accuracy image capturing using the obtained scintillator panel.

  The bottom width (Lb) of the partition walls is preferably 20 to 150 μm, and the top width (Lt) of the partition walls is preferably 15 to 80 μm. If the bottom width of the partition is less than 20 μm, defects in the partition are likely to occur during firing. On the other hand, when the bottom width of the partition wall is increased, the amount of phosphor that can be filled in the space partitioned by the partition wall is reduced. When the top width of the partition is less than 15 μm, the strength of the partition is lowered. On the other hand, when the top width of the partition wall exceeds 80 μm, the region where the light emitted from the scintillator layer can be extracted becomes narrow. The aspect ratio (H / Lb) of the partition wall height (H) to the partition wall bottom width (Lb) is preferably 1.0 to 25.0. The higher the aspect ratio (H / Lb) with respect to the bottom width of the barrier rib, the wider the space per pixel divided by the barrier ribs, and the more phosphors can be filled.

  The aspect ratio (H / P) of the partition wall height (H) to the partition wall pitch (P) is preferably 0.1 to 3.5. A partition wall having a higher aspect ratio (H / P) with respect to the partition wall pitch is one pixel divided with higher definition, and more phosphor can be filled in a space per pixel.

  As the shape of the cells partitioned by the lattice-shaped partition walls, a shape such as a square, a rectangle, a parallelogram, and a trapezoid can be appropriately selected. In the scintillator panel of the present invention, from the viewpoint of the uniformity of the bottom width of the partition walls and the uniformity of the phosphor emission intensity within one pixel, a grid-like partition wall having a square cell shape is preferable. It is not limited.

  The height and width of the partition walls were measured by exposing a section of the partition walls perpendicular to the substrate and observing the section with a scanning electron microscope (Hitachi, S2400). The width of the partition wall at the contact portion between the partition wall and the substrate was measured as the bottom width (Lb). When there was 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 was measured as the bottom width (Lb). Moreover, the width | variety of the partition topmost part was measured as top part width (Lt).

  The partition walls are formed by sintering inorganic powder contained in the photosensitive paste. The inorganic powders forming the partition walls are fused, but voids remain between them. The ratio of the voids included in the partition walls can be adjusted by the temperature design of the firing process for firing the partition walls. By setting the ratio of the void portion (void ratio) to the entire partition wall to be 2 to 25%, it is possible to form a partition wall having both visible light reflection characteristics and strength, which is preferable. When the porosity is less than 2%, the light emission luminance of the obtained scintillator panel is lowered due to the low reflectance of the partition walls. When the porosity exceeds 25%, the strength of the partition wall is insufficient, and it tends to collapse. In order to achieve both reflection characteristics and strength, the porosity is more preferably 5 to 25%, further preferably 5 to 20%.

  The porosity is measured by precisely polishing the cross section of the partition wall, then observing with an electron microscope, converting the inorganic material part and the void part into two gradations, and determining the ratio of the area of the void part closed to the area of the partition wall cross section. calculate.

  Moreover, it is preferable to provide the buffer layer which consists of an inorganic component chosen from low melting glass and ceramics between a partition and a board | substrate. The buffer layer has an effect of relaxing the stress applied to the partition walls in the firing step and realizing stable partition formation. In addition, it is preferable that the buffer layer has a high reflectance because the light emission luminance of the scintillator panel can be increased by reflecting visible light emitted by the phosphor in the direction of the photoelectric conversion element. In order to increase the reflectance, the buffer layer is preferably made of low-melting glass and ceramics. As the low melting point glass, the same glass as the partition wall can be used. As the ceramic, titanium oxide, aluminum oxide, zirconium oxide and the like are preferable.

  In order to form the buffer layer, a paste in which an organic component and an inorganic powder such as a low-melting glass powder or a ceramic powder are dispersed in a solvent is applied to a substrate and dried to form a buffer layer paste coating film. Next, the buffer layer can be formed by baking the paste coating film for the buffer layer at a temperature of preferably 500 to 700 ° C., more preferably 500 to 650 ° C.

  It is also possible to carry out the firing of the buffer layer and the firing of the partition walls at the same time. By using this simultaneous firing, the number of firing steps can be reduced, and energy consumed in the firing step can be reduced. When simultaneous firing of the buffer layer and the partition wall is used, the buffer layer paste coating film is formed using the photosensitive organic component similar to the above-described partition wall photosensitive paste as the organic component of the buffer layer paste, It is preferable to expose the entire surface of the paste coating film for curing and cure the coating film. Further, as the organic component of the buffer layer paste, a buffer layer paste using a thermosetting organic component containing any polymerizable compound selected from a polymerizable monomer, a polymerizable oligomer and a polymerizable polymer, and a thermal polymerization initiator, It is also preferable to heat cure after forming the coating film. Since these methods make the buffer layer paste coating film insoluble in the solvent, the buffer layer paste coating film is prevented from dissolving or peeling off in the step of applying the barrier rib photosensitive paste thereon. be able to.

  In addition to the above components, a binder such as ethyl cellulose, a dispersant, a thickener, a plasticizer, an antisettling agent, and the like can be appropriately added to the thermosetting buffer layer paste.

  The reflectance of the buffer layer with respect to a wavelength of 550 nm is preferably 60% or more. By setting the reflectance of the buffer layer to 60% or more, the emitted light of the panel does not pass through the buffer layer, and the emitted light can be effectively extracted to the output substrate side.

  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, CsI is preferable because it has a relatively high conversion rate from X-rays to visible light and high reflectivity due to phosphor crystals. Moreover, in order to improve luminous efficiency, you may add various activators to CsI. For example, a mixture of CsI and sodium iodide (NaI) at an arbitrary molar ratio, indium (In), thallium (Tl), lithium (Li), potassium (K), rubidium (Rb), sodium (Na) CsI containing an activator such as is preferable. Further, thallium compounds such as thallium bromide (TlBr), thallium chloride (TlCl), or thallium fluoride (TlF, TlF ₃ ) can 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, phosphor binder prepared by mixing organic binders such as ethyl cellulose and acrylic resin, and organic solvents such as terpineol and γ-butyrolactone, etc. it can.

  The amount of phosphor filled in the cell partitioned by the partition wall is such that the volume fraction occupied by the phosphor (hereinafter, phosphor volume filling factor) is 55% to 100% with respect to the space volume in the cell. It is preferably 60% to 100%, more preferably 70% to 100%. If the phosphor volume fraction is less than 55%, incident X-rays cannot be efficiently converted into visible light. In order to increase the conversion efficiency of incident X-rays, it is preferable to fill the space of the cell with a high density of phosphors.

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 monomer M-3: In the following formula (A), R ¹ and R ² are acryloyl groups, and R ³ is Ethylene oxide-propylene oxide co-oligomer, R ⁴ is isophorone diisocyanate residue, molecular weight is 19,000
_{^{R 1 - (R 4 -R 3}} ) n -R 4 -R 2 (A)
Photosensitive polymer: methacrylic acid / methyl methacrylate / styrene = 40/30/30 copolymer obtained by addition reaction of 0.4 equivalent of glycidyl methacrylate to a 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 solvent: γ-butyrolactone viscosity modifier: Flownon EC121 (manufactured by Kyoeisha Chemical Co., Ltd.)
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, softening temperature 588 ° C., thermal expansion coefficient 68 × 10 ⁻⁷ , 50% volume average particle diameter 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 , 50% volume average particle diameter 2.1 μm
Low melting glass powder C:
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, softening temperature 540 ° C., thermal expansion coefficient 86 × 10 ⁻⁷ , 50% volume average particle diameter 2.2 μm
High melting point glass powder:
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 , 50% volume average particle diameter 2.3 μm
White pigment A:
Aluminum oxide white pigment B having an average particle size of 0.08 μm:
Zirconium oxide white pigment C having an average particle size of 0.03 μm:
Titanium oxide white pigment D having an average particle diameter of 0.005 μm:
Titanium oxide with an average particle size of 0.3μm (Preparation of partition wall paste)
Using the above materials, a barrier rib paste was prepared by the following method.

  Photosensitive paste A for partition walls: 8 parts by weight of photosensitive monomer M-1, 6 parts by weight of photosensitive monomer M-2, 6 parts by weight of photosensitive monomer M-3, 48 parts by weight of photosensitive polymer, start of photopolymerization 12 parts by mass of the agent, 0.4 part by mass of the polymerization inhibitor and 25.6 parts by mass of the ultraviolet absorbent solution were dissolved in 76 parts by mass of the solvent at a temperature of 80 ° C. After cooling the obtained solution, 18 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 and drying the organic solution 1 on a glass substrate was 1.555.

  Next, 80 parts by mass of the low-melting glass powder A, 19.9 parts by mass of the high-melting glass powder, and 0.1 part by mass of the white pigment A are added to 150 parts by mass of the prepared organic solution 1, and then three It knead | mixed with the roller kneader and the photosensitive paste A for partition was produced.

  Barrier photosensitive paste B: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 19.9 parts by mass of the high-melting glass powder, and 0.1 part by mass of the white pigment B are added to 150 parts by mass of the prepared organic solution 1, and then three It knead | mixed with the roller kneader and the photosensitive paste B for partition was produced.

  Barrier photosensitive paste C: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 19.9 parts by mass of the high-melting glass powder, and 0.1 part by mass of the white pigment C are added to 150 parts by mass of the organic solution 1 thus prepared. It knead | mixed with the roller kneader and the photosensitive paste C for partition was produced.

  Barrier photosensitive paste D: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 18 parts by mass of the high-melting glass powder, and 2 parts by mass of the white pigment C are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare a photosensitive paste D for barrier ribs.

  Barrier photosensitive paste E: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 15 parts by mass of the high-melting glass powder, and 5 parts by mass of the white pigment C are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare photosensitive paste E for barrier ribs.

  Barrier photosensitive paste F: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 10 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment C are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare a photosensitive paste F for barrier ribs.

  Barrier photosensitive paste G: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 60 parts by mass of the low melting glass powder A and 40 parts by mass of the white pigment C are added to 150 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader to form a photosensitive paste for partition walls. G was produced.

  Barrier photosensitive paste H: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 10 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment A are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare a photosensitive paste H for partition walls.

  Barrier photosensitive paste I: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 10 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment B are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare a photosensitive paste I for barrier ribs.

  Barrier photosensitive paste J: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder B, 10 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment C are added to 150 parts by mass of the organic solution 1 thus prepared. And kneaded to prepare a photosensitive paste J for barrier ribs.

  Barrier photosensitive paste K: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder C, 10 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment C are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare a photosensitive paste K for partition walls.

  Barrier photosensitive paste L: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A, 10 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment D are added to 150 parts by mass of the prepared organic solution 1, and then added to the three-roller kneader. And kneaded to prepare a photosensitive paste L for barrier ribs.

  Barrier photosensitive paste M: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 80 parts by mass of the low-melting glass powder A and 20 parts by mass of the high-melting glass powder were added to 150 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader, and photosensitive for the partition wall. Paste M was prepared.

  Barrier photosensitive paste N: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, 55 parts by mass of low-melting glass powder A and 45 parts by mass of white pigment C are added to 150 parts by mass of the prepared organic solution 1, and then kneaded with a three-roller kneader to form a photosensitive paste for partition walls. N was produced.

  Barrier photosensitive paste O: An organic solution 1 was prepared in the same manner as the barrier rib photosensitive paste A. Next, after adding 40 parts by mass of the low-melting glass powder A, 50 parts by mass of the high-melting glass powder, and 10 parts by mass of the white pigment C to 150 parts by mass of the prepared organic solution 1, the mixture is added to the three-roller kneader. And kneaded to prepare a photosensitive paste O for partition walls.

(Measurement of emission luminance)
The produced scintillator panel was set in PaxScan2520, and the radiation detection apparatus was produced. X-rays with 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. The evaluation of luminance was performed by relative evaluation with the result of Example 1 as 100%.

Example 1
The above-mentioned photosensitive paste A for partition walls is dried to 500 μm on a 500 mm × 500 mm glass substrate (OA-10, manufactured by Nippon Electric Glass Co., Ltd., thermal expansion coefficient 38 × 10 ⁻⁷ , substrate thickness 0.7 mm). Then, it was coated with a die coater and dried to form a photosensitive paste coating film for partition walls. Next, the photosensitive paste coating film for barrier ribs is applied to an ultrahigh pressure via a photomask (a chromium mask having a grid-like opening having a pitch of 127 μm in both vertical and horizontal directions and a line width of 20 μm) in which openings corresponding to a desired barrier rib pattern are formed. Exposure was performed at 600 mJ / cm ² with a mercury lamp. 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 to obtain a partition member having a grid partition with a partition pitch of 127 μm and a size of 480 mm × 480 mm. The average particle diameter of the agglomerated particles of the white pigment in the obtained partition walls was 0.7 μm.

  Thereafter, CsI: Tl (CsI: TlI = 1 mol: 0.003 mol) is filled as a phosphor into the space defined by the partition walls, and is fired at 580 ° C. to produce a scintillator panel 1 having a phosphor volume filling rate of 85%. did. As a result of evaluating the radiation detection apparatus including the manufactured scintillator panel 1 and PaxScan 2520, a good image was obtained.

Example 2
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste B was used as the barrier rib photosensitive paste. The average particle diameter of the agglomerated particles of the white pigment in the obtained partition walls was 0.5 μm. The relative luminance was 102%, and a good image was obtained.

Example 3
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste C was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 0.3 μm. The relative luminance was 104%, and a good image was obtained.

Example 4
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste D was used as the barrier rib photosensitive paste. The average particle diameter of the agglomerated particles of the white pigment in the obtained partition walls was 0.5 μm. The relative luminance was 110%, and a good image was obtained.

Example 5
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste E was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 0.8 μm. The relative luminance was 120%, and a good image was obtained.

Example 6
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste F was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 1.0 μm. The relative luminance was 125%, and a good image was obtained.

Example 7
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste G was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 2.0 μm. The relative luminance was 125%, and a good image was obtained.

Example 8
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste H was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 1.5 μm. The relative luminance was 115%, and a good image was obtained.

Example 9
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste I was used as the barrier rib photosensitive paste. The average particle diameter of the agglomerated particles of the white pigment in the obtained partition walls was 1.2 μm. The relative luminance was 120%, and a good image was obtained.

Example 10
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste J was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 0.8 μm. The relative luminance was 125%, and a good image was obtained.

Example 11
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste K was used as the barrier rib photosensitive paste. The average particle diameter of the aggregated particles of the white pigment in the obtained partition wall was 0.8 μm. The relative luminance was 125%, and a good image was obtained.

Example 12
An alignment mark is formed on a 500 mm × 500 mm glass substrate (OA-10 manufactured by Nippon Electric Glass Co., Ltd., thermal expansion coefficient 38 × 10 ⁻⁷ , substrate thickness 0.7 mm), and then the above-mentioned photosensitive paste L for partition is dried. The film was applied with a die coater so as to have a thickness of 100 μm and dried to form a photosensitive paste coating film for partition walls. Next, the photosensitive paste coating film for barrier ribs is applied to an ultrahigh pressure via a photomask (a chromium mask having a grid-like opening having a pitch of 127 μm in both vertical and horizontal directions and a line width of 20 μm) in which openings corresponding to a desired barrier rib pattern are formed. Exposure was performed at 100 mJ / cm ² with a mercury lamp. The barrier rib photosensitive paste L is further applied to the barrier rib photosensitive paste coating film by a die coater so as to have a dry thickness of 100 μm, and the same position as the first exposure is applied using the same mask as the first exposure. Were aligned and exposed at 100 mJ / cm ² . This coating, drying, and exposure process was repeated three more times to obtain an exposed partition wall paste coating film having a dry thickness of 500 μm. Next, development was performed in a 0.5% ethanolamine aqueous solution to remove unexposed portions, thereby forming a lattice-like photosensitive paste coating film pattern. Further, the photosensitive paste coating film pattern was baked in the air at 585 ° C. for 15 minutes to obtain a partition member having a grid partition with a partition pitch of 127 μm and a size of 480 mm × 480 mm. The average particle diameter of the agglomerated particles of the white pigment in the obtained partition walls was 1.2 μm.

  Thereafter, CsI: Tl (CsI: TlI = 1 mol: 0.003 mol) is filled as a phosphor into the space defined by the partition walls, and is fired at 580 ° C. to produce a scintillator panel 1 having a phosphor volume filling rate of 85%. did. As a result of evaluating the radiation detection apparatus comprising the manufactured scintillator panel 1 and PaxScan 2520, the relative luminance was 125%, and a good image was obtained.

Comparative Example 1
Evaluation was performed in the same manner as in Example 1 except that the above-described barrier rib photosensitive paste M was used as the barrier rib photosensitive paste. The relative luminance was 95%, and the image was defective because the luminance was low.

Comparative Example 2
A partition wall was formed in the same manner as in Example 1 except that the above-described partition wall photosensitive paste N was used as the partition wall photosensitive paste. After that, when the phosphor was filled, a large number of breaks occurred in the partition walls, so that light leaked from the damaged partition walls and a clear image could not be obtained.

Comparative Example 3
A partition wall was formed in the same manner as in Example 1 except that the above-described partition wall photosensitive paste O was used as the partition wall photosensitive paste. After that, when the phosphor was filled, a large number of breaks occurred in the partition walls, so that light leaked from the damaged partition walls and a clear image could not be obtained.

  From these results, it can be seen that in the embodiment according to the present invention, a radiation detection apparatus having high emission luminance and capable of obtaining 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

Claims (5)

A scintillator panel having a flat substrate, a grid-like partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition,
The said partition is a scintillator panel comprised by the material which has low melting glass as a main component and contains 0.1-40 mass% of white pigments.   The scintillator panel according to claim 1, wherein the white pigment is a metal oxide selected from the group consisting of aluminum oxide, zirconium oxide, and titanium oxide.   The scintillator panel according to claim 1 or 2, wherein the low melting point glass contains 2 to 20% by mass of an alkali metal oxide.   The scintillator panel according to any one of claims 1 to 3, wherein an average particle diameter of the aggregated particles of the white pigment is 0.3 to 2 µm. A method of manufacturing a scintillator panel having a flat substrate, a grid-shaped partition provided on the substrate, and a scintillator layer made of a phosphor filled in a cell partitioned by the partition,
Applying a photosensitive paste containing a low-melting glass powder, a white pigment and a photosensitive organic component on a substrate to form a photosensitive paste coating film;
A step of exposing the obtained photosensitive paste coating film through a photomask having a predetermined opening;
A development process for dissolving and removing a portion soluble in the developer of the photosensitive paste coating film after exposure,
A baking process in which the photosensitive paste coating film pattern after development is heated to 500 ° C. to 700 ° C. to remove organic components and soften and sinter low-melting glass to form partition walls; and
Filling the phosphor into the cells partitioned by the partition;
A method of manufacturing a scintillator panel including:

Images