JP6075028B2 - Scintillator panel - Google Patents

Description

  The present invention relates to a scintillator panel.

  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-ray, and the light is emitted by a TFT or CCD. Is converted into digital image information. However, FPD has a problem that the S / N ratio is low. As a method for increasing the S / N ratio, there are a method of irradiating X-rays from the photodetector side (Patent Documents 1 and 2), and a partition wall in order to reduce the influence of scattering of visible light by the X-ray phosphor. There has been proposed a method of filling an X-ray phosphor in a cell partitioned by (Patent Documents 3 to 6).

  As a method for forming such a partition wall, conventionally used methods are a method of etching a silicon wafer, or a glass paste which is a mixture of a pigment or ceramic powder and a low-melting glass powder by a screen printing method. And a method of forming a partition wall by baking after pattern printing. However, 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 multi-layer screen printing method using glass paste, high-precision processing is difficult due to dimensional changes of the screen printing plate. Further, when performing multi-layer screen printing, in order to increase the strength of the partition wall in order to prevent the collapse defect of the partition wall, a certain partition wall width is required. 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 becomes weak and light emission unevenness occurs. This is an obstacle to clear imaging in low-dose imaging.

  In other words, in order to produce a scintillator panel that has high luminous efficiency and realizes a clear image quality, the processing technology of the partition that can process a large area with high accuracy and the width of the partition can be reduced, and the phosphor emits light. There is a need for technology that prevents visible light from leaking outside the partition walls.

Japanese Patent No. 3333278 JP 2001-330677 A Japanese Patent Laid-Open No. 5-60871 JP-A-5-188148 JP 2011-007552 A JP 2011-021924 A

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

This object is achieved by any of the following technical means.
( 1 ) A flat substrate, a plurality of main partitions formed in parallel on the substrate, an auxiliary partition formed perpendicular to the main partition, and a cell partitioned by the main partition A scintillator panel made of a filled phosphor, wherein the pitch P1 of the main barrier ribs and the pitch P2 of the auxiliary barrier ribs satisfy the relationship P1 <P2, and the height H1 of the main barrier ribs and the auxiliary barrier ribs A scintillator panel in which the height H2 satisfies the relationship of H1> H2.
( 2 ) The scintillator panel according to ( 1 ), wherein the H1 and the H2 satisfy a relationship of H1 × 0.5 ≦ H2 ≦ H1 × 0.9.
( 3 ) The scintillator panel according to (1) or (2) , wherein a reflective layer is formed on the surface of the main partition wall.
( 4 ) Any of the above (1) to ( 3 ), wherein the main partition wall and the auxiliary partition wall are made of a material mainly composed of low melting point glass containing 2 to 20% by mass of an alkali metal oxide. The scintillator panel described in 1.

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

  Hereinafter, although the preferable structure of the scintillator panel of this invention and a radiation detection apparatus using the same is demonstrated using FIGS. 1-4, this invention is not limited to these.

  1 and 2 are cross-sectional views schematically showing the configuration of a radiation detection apparatus including the scintillator panel of the present invention. 3 and 4 are perspective views schematically showing the configuration of an example of the scintillator panel of the present invention. The radiation detection apparatus 1 includes a scintillator panel 2 and a photodetector 3. 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. Emits electromagnetic waves (light) in the range of infrared light.

  The scintillator panel 2 includes a scintillator panel-side substrate 4, a plurality of parallel main partition walls 6A for partitioning cells formed thereon, and fluorescence filled in a space formed by the main partition walls. The scintillator layer 7 is made of a body. The main partition wall 6A needs to be formed with at least two or more main partition walls 6A in order to partition cells. The plurality of main partition walls 6A are formed in parallel to each other, that is, in a stripe shape. Further, as shown in FIG. 3, the auxiliary partition 6B is formed so as to be perpendicular to the main partition 6A. Radiation may be incident from either the scintillator panel side or the photodetector side. It is preferable that a radiation shielding layer 5 is formed between the substrate on which radiation is not incident and the main partition wall 6A and the auxiliary partition wall 6B. For example, since the scintillator panel 2 shown in FIG. 1 is a mode in which radiation enters from the photodetector 3 side, the substrate on the side on which radiation does not enter, that is, the scintillator panel side substrate 4 and the main partition wall 6A, A radiation shielding layer 5 is formed. The radiation shielding layer 5 absorbs the radiation that has passed through the scintillator layer 7 and can shield radiation leakage to the outside of the radiation detection apparatus. The radiation shielding layer 5 preferably has a high visible light reflectance. Moreover, it is preferable that a reflective layer 8 is formed on the scintillator panel side substrate 4 or the radiation shielding layer 5. By these reflective layers, visible light emitted from the phosphor 7 can be efficiently guided to the photodetector 3 side.

  The photodetector 3 includes a photodetector-side substrate 10 and a photoelectric conversion layer 9 formed thereon. Here, the photoelectric conversion layer 9 is formed by two-dimensionally forming a pixel composed of a photosensor and a TFT. The radiation detection apparatus 1 is configured by bonding a scintillator panel 2 and a photoelectric conversion layer 9 of a photodetector 3 so as to face each other. It is preferable that an adhesive layer 11 made of a polyimide resin or the like is formed between the main partition 6 </ b> A and the scintillator layer 7 of the scintillator panel 2 and the photodetector 3. For example, radiation incident from the photodetector 3 side passes through the photoelectric conversion layer 9 and is then converted into visible light by the scintillator layer 7. The visible light is detected and photoelectrically converted by the photoelectric conversion layer 9 and output. .

  In order to increase the sharpness of the radiation detection apparatus 1, the main partition wall 6 </ b> A of the scintillator panel 2 is preferably located between the photoelectric conversion layers 9. Each cell of the scintillator panel 2 is partitioned by a partition wall, and the phosphor and phosphor are formed by matching the size and pitch of the photoelectric conversion layer 9 formed in a stripe shape or matrix shape with the cell pitch of the scintillator panel 2. Even if light is scattered by the light, it is possible to prevent the scattered light from reaching the adjacent cell. As a result, blurring of the image due to light scattering can be reduced, and high-accuracy imaging can be performed.

  By forming the auxiliary partition wall 6B so as to be perpendicular to the main partition wall 6A formed in parallel on the substrate, meandering and tilting of the main partition wall can be prevented, but the partition wall height with respect to the partition wall width of the main partition wall The ratio (aspect ratio) is preferably large.

In order to ensure sufficient luminance, the pitch P1 of the main partition walls 6A and the pitch P2 of the auxiliary partition walls 6B (when a plurality of auxiliary partition walls are formed) are:
P1 <P2
It is preferable to satisfy the relationship.

Further, in order to improve the uniformity and design of the scintillator panel by forming the auxiliary partition wall 6B between the photoelectric conversion layers 9 while ensuring sufficient luminance, P1 and P2 are:
P2 = P1 × n (n is an arbitrary integer other than 1)
It is more preferable to satisfy the relationship. In addition, a pitch means the space | interval between the mutual side surfaces of the adjacent main partition or auxiliary partition here.

Furthermore, in order to effectively suppress meandering and tilting of the main partition wall while ensuring sufficient brightness and sharpness, P1 and P2 are:
P1 × 2 ≦ P2 ≦ P1 × 20
It is more preferable to satisfy this relationship.

In order to increase the filling amount of the phosphor, the height H2 of the auxiliary partition 6B is preferably lower than the height H1 of the main partition 6A. On the other hand, if the auxiliary partition wall is too low, the strength of the main partition wall is insufficient, and the light diffusion increases and blurring occurs, so that H1 and H2 are H1 × 0.1 ≦ H2 ≦ H1 × 0.9.
It is preferable to satisfy the relationship
H1 × 0.5 ≦ H2 ≦ H1 × 0.9
It is more preferable to satisfy the relationship.

  A reflective layer 8 is preferably formed on the surface of the main partition wall 6A. By forming the reflective layer, visible light emitted in the cell can be efficiently guided to the photodetector 3. In addition, as shown in FIG. 2, it is also preferable to form the reflective layer 8 only on one side surface of the main partition wall 6A. Light emitted from the phosphor in the cell is not scattered outside the cell, and high-accuracy imaging is possible. On the other hand, on the side where the reflective layer is not formed, the emitted light of the phosphor in the cell is transmitted through the partition wall, but is not scattered by the reflective layer formed on the side surface on the opposite side. Accurate shooting is possible. And since the emitted light which permeate | transmitted the main partition 6A can be guide | induced to the photodetector 3, a brightness | luminance improves and it can utilize especially the emitted light of the fluorescent substance located away from the photodetector 3 with high efficiency. it can. The transmittance of the partition walls at this time is preferably higher in order to transmit light, and a partition wall in which the transmittance of light at 550 nm at a thickness of 30 μm is in the range of 10 to 100% is most preferable.

  When the reflective layer is formed only on one side of the main partition, the reflective layer is regularly formed only on one side of the main partition as shown in FIG. 2 in order to ensure the uniformity of the entire scintillator panel. It is preferable. On the other hand, in order to increase productivity, as shown in FIG. 4, as shown in FIG. 4, a cell A in which a reflective layer is formed on all inner side surfaces of two partition walls constituting the cell, and a reflective layer on all inner side surfaces. The reflective layer is preferably formed so as to be distinguished from the cell B that is not formed. In this case, as shown in FIG. 4, it is more preferable that the cells A or the cells B are arranged so as not to be adjacent to each other. It is more preferable that the pitch of the cell A is wider than the pitch of the cell B and the capacity of the cell A is larger than the capacity of the cell B in order to ensure the in-plane uniformity of luminance.

  When radiation is incident from the scintillator panel side, the material of the scintillator panel side substrate 4 is preferably a material having high radiation transparency, and various types of glass, polymer materials, metals, and the like can be used. 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, a film and plate glass are preferable at the point of flatness and heat resistance. In order to pursue the convenience of carrying around the scintillator panel, weight reduction has been promoted, and thus the plate glass is preferably a thin plate glass.

  On the other hand, when the radiation is incident from the photodetector side, the scintillator panel side substrate 4 may be made of a material having a radiation transmissive material, but the radiation to the outside of the radiation detection apparatus may be used. In order to shield leakage, it is preferable to use a substrate made of a radiation shielding material, that is, a radiation shielding substrate. Examples of the radiation shielding substrate include a metal plate such as an iron plate or a lead plate, or a glass plate or film containing a heavy metal such as iron, lead, gold, silver, copper, platinum, tungsten, bismuth, tantalum, or molybdenum. In addition, when the radiation shielding layer 5 is formed between the substrate on which radiation is not incident and the partition wall 6, the necessity that the scintillator panel side substrate 4 is a radiation shielding substrate is reduced.

  Examples of the material of the radiation shielding layer 5 include materials capable of absorbing radiation such as glass or ceramics containing heavy metals such as iron, lead, gold, silver, copper, platinum, tungsten, bismuth, tantalum, and molybdenum. .

  The radiation shielding layer 5 is formed, for example, by applying and drying a paste in which an organic component and an inorganic powder are dispersed in a solvent on a substrate to form a coating film, which is preferably 500 to 700 ° C., more preferably 500 to 650 ° C. It can form by baking at the temperature of.

  Moreover, it is preferable that the radiation shielding layer and the partition walls be fired at the same time because the number of steps is reduced. In addition, in order to prevent dissolution and peeling when the partition wall paste is applied, it contains a polymerizable monomer, a polymerizable oligomer or a polymerizable polymer that is an organic component of the radiation shielding layer paste, and a thermal polymerization initiator. It is also preferable to use a thermosetting organic component to form and heat cure after forming a coating film.

  The main partition wall and the auxiliary partition wall are preferably 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. The main component is low melting glass containing 2 to 20% by weight of alkali metal oxide, which means that 50 to 100% by weight of the material constituting the partition contains 2 to 20% by weight of alkali metal oxide. The low melting point glass.

  The scintillator panel manufacturing method applies a photosensitive paste containing a low-melting glass and a photosensitive organic component on a substrate in order to process a large area with high accuracy and reduce the width of the partition wall. A step of forming a paste coating film, an exposure step of exposing the obtained photosensitive paste coating film through a photomask having a predetermined opening, and a portion soluble in the developer of the photosensitive paste coating film after exposure. A development step for dissolving and removing, a baking step for forming the partition walls by heating the photosensitive paste coating film pattern after development to a firing temperature of 500 to 700 ° C. to remove organic components and softening and sintering the low melting glass. It is preferable to provide a step of forming a metallic reflective layer by a vacuum film formation method and a step of filling a phosphor at a temperature lower than the firing temperature.

  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 firing step, the resulting photosensitive paste coating film pattern is fired at a temperature of 500 to 700 ° C., preferably 500 to 650 ° C., whereby organic components are decomposed and distilled, and the low-melting glass is softened. And sintered to form a partition including a 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.

  By this method, processing with higher accuracy is possible than a processing method in which glass paste is laminated and printed by multilayer screen printing and then fired.

  The photosensitive paste is preferably composed of an organic component containing a photosensitive organic component and an inorganic powder containing a low melting point glass containing 2 to 20% by mass of an alkali metal oxide. 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 point 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. The alkali metal oxide used in the present invention refers to 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 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 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 increases, and when an amount exceeding 10% by mass is added, the cost of the glass tends to increase.

  Furthermore, in addition to the above alkali metal oxide and zinc oxide, the low melting point glass contains silicon oxide, boron oxide, aluminum oxide, alkaline earth metal oxide, or the like, 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 refers to 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 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 even at 700 ° C. or ceramic particles such as silicon oxide, aluminum oxide, titanium oxide, or zirconium oxide, in addition to the above-described low melting point glass. 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. Moreover, it is preferable that a filler is an average particle diameter of 0.5-4.0 micrometers for the same reason as low melting glass.

  In the photosensitive paste composition used in the present invention, the refractive index n1 of the low-melting glass and the refractive index n2 of the photosensitive organic component preferably satisfy −0.1 <n1-n2 <0.1, and −0. It is more preferable to satisfy 01 ≦ n1-n2 ≦ 0.01, and it is further 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 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, a low melting point glass having both preferable thermal characteristics and a preferable 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 at a wavelength of 436 nm (g line) at 25 ° C. was defined as the refractive index of the low-melting glass in the present invention. The 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 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, 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 the organic component increases the crosslink density at the time of curing by photoreaction, and the pattern formability is increased. 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 carboxylic acid-containing monomers such as these acid anhydrides 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 is used. 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 a low-melting glass as the glass, it is possible to suppress a pattern defect that abrupt shrinkage hardly occurs in the process of sintering the glass in the latter stage of the firing process. 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, Naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, benzthiazole disulfide, triphenylformine, benzoin peroxide and eosin, methylene blue and other photoreductive dyes such as 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. Examples of the copolymer having a carboxyl group include, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid or a carboxylic acid-containing monomer such as these acid anhydrides and methacrylic acid ester, acrylic acid Other monomers such as acid 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 during 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 composed of a low-melting glass and a photosensitive monomer, a photosensitive oligomer, a photosensitive polymer, a photopolymerization initiator, or the like as necessary. 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 main barrier rib and the auxiliary barrier rib are manufactured by the photolithography method using the photosensitive paste will be described, the present invention is not limited to this.

  On the substrate, the photosensitive paste coating film of the first layer is formed by coating the entire surface or a part of the photosensitive paste so that the height after baking of the photosensitive paste becomes the desired height of the auxiliary barrier ribs. As a coating method, a screen printing method, a bar coater, a roll coater, a die coater, a blade coater or the like 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. In this case, mask exposure is performed using a photomask having openings corresponding to the auxiliary partition pattern. In addition, 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. At this time, examples of the actinic rays used include near infrared rays, visible rays, and ultraviolet rays. Among these, ultraviolet rays are preferable. As the light source, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a halogen lamp, or a germicidal lamp can be used, and an ultra-high 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 .

  On the exposed photosensitive paste coating film of the first layer, the photosensitive paste is further applied after baking so that the height becomes the desired height of the main partition wall, and then dried, and then the second photosensitive layer is exposed. An adhesive paste coating film is formed. Note that the first and second photosensitive pastes may be the same.

  As in the case of the first layer, the exposure process is performed. In the case of performing exposure through a photomask, mask exposure is performed using a photomask having an opening portion in a direction perpendicular to the auxiliary barrier rib corresponding to the pattern of the main barrier rib.

  After the exposure of the second layer, the photosensitive paste coating film is developed using a difference in solubility between the exposed portion and the unexposed portion of the developer in the developer, and a photosensitive paste coating film having a lattice shape including desired main partition walls and auxiliary partition walls Get a pattern. Development is performed by a dipping method, a spray method or a brush method. 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 point glass contained in the coating film pattern is softened and sintered, so that the lattice is substantially made of an inorganic material on the substrate. A partition member in which a partition wall is formed is obtained.

  The material of the reflective layer is not particularly limited, but it is preferable to use a material that reflects visible light, which is an electromagnetic wave of 300 to 800 nm emitted from the phosphor. Among them, metals or metal oxides such as silver, gold, aluminum, nickel, and titanium with little deterioration are preferable.

  The method for forming the reflective layer is not particularly limited, and various film formation methods such as a method of pasting a reflective material and applying it to the surface, and then baking and removing the solvent, a spraying method by spraying and a plating method can be used. I can do it. Among these, vacuum film formation methods such as vapor deposition, sputtering, ion plating, CVD, or laser ablation are preferable because a uniform reflective layer can be formed at a lower temperature, and sputtering is more preferable because a uniform film can be formed on the side wall of the partition. In addition, when a temperature higher than the firing temperature of the partition is applied during the formation of the reflective layer, the partition is deformed. Therefore, the temperature during the formation of the reflective layer is preferably lower than the temperature during the formation of the partition.

  The reflective layer preferably uses 60% or more, and more preferably 80% or more of the reflectance of light having a wavelength of 550 nm in order to efficiently use the emitted light.

  As a method of forming the reflective layer only on one side surface of the partition wall, for example, a method of tilting the substrate by 45 degrees or more with respect to a metal sputtering target in a sputtering method, or a side surface on which the reflective layer is not formed is masked with a resin or the like. Then, the reflective layer is formed, and then the masking material is removed.

  As a method for forming a reflective layer in a specific cell, for example, a reflective layer paste containing a reflective layer powder, an organic binder, and an organic solvent as main components is prepared, applied to the target cell, and dried. The method of baking as needed is mentioned. Here, as a method of applying the reflective layer paste in the cell, for example, a screen printing method of pattern printing using a screen printing plate, a dispenser method of applying a reflective layer paste from the tip of a discharge nozzle, or an inkjet method Or the photosensitive paste method using the paste for reflective layers containing a photosensitive organic component is mentioned.

  In order to improve the reflectance of light and prevent transmission, it is preferable that a light shielding film is formed between the main partition and the reflective layer. The material of the light shielding film is not particularly limited, and a metal film such as chromium, nichrome, or tantalum, a resin containing a black pigment such as carbon, or the like can be used. The formation method is not particularly limited, and a method of applying a pasted material or various vacuum film forming methods can be used.

  H1 is preferably 100 to 3000 μm, and more preferably 150 to 500 μm. If H1 exceeds 3000 μm, pattern formation during processing becomes difficult. On the other hand, when H1 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.

  P1 is preferably 30 to 1000 μm. If P1 is less than 30 μm, pattern formation during processing becomes difficult. On the other hand, if P1 is too large, it is difficult to perform high-accuracy image capturing using the obtained scintillator panel. In the present invention, H1 is preferably larger than P1.

  In the main partition wall and the auxiliary partition wall, the width (bottom width) L2 of the surface where the partition wall and the substrate are in contact with each other is preferably larger than the width L1 of the top (photodetector side) of the partition wall. By adopting a pseudo trapezoidal structure in which the partition wall width on the photodetector side is narrower, the reflection efficiency and extraction efficiency of the emitted light of the scintillator layer can be improved. In addition, when radiation is incident from the photodetector side, the use efficiency of the radiation can be increased by increasing the filling amount of the phosphor near the photodetector side. Further, when the reflective layer is formed on the partition surface after the partition is formed, if L1 is larger than L2, the side wall of the partition near the top of the partition may be behind the top of the partition and the reflective layer may not be formed.

  L2 is preferably 10 to 150 μm, and L1 is preferably 5 to 80 μm. If L2 is less than 10 μm, defects in the partition walls are likely to occur during firing. On the other hand, when L2 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 L1 is less than 5 micrometers. On the other hand, when L1 exceeds 80 μm, the region where the light emitted from the scintillator layer can be extracted becomes narrow. In order to increase the sharpness of the radiation detection apparatus, it is preferable that a partition wall is located between the photoelectric conversion layers, and it is more preferable that L1 is shorter than the interval between the photoelectric conversion layers.

  The aspect ratio (H1 / L2) of H1 to L2 is preferably 1.0 to 25.0. The larger the aspect ratio (H1 / L2), the wider the space per pixel partitioned by the partition, and the more phosphor can be filled.

  The aspect ratio (H1 / P1) of H1 with respect to P1 is preferably 1.0 to 3.5. The higher the aspect ratio (H1 / P1), the higher the partition is, and the more fine phosphors can be filled in the space per pixel.

  H1 and P1 can be measured by exposing the cross section of the partition perpendicular to the substrate and observing the cross section with a scanning electron microscope (“S4600” manufactured by Hitachi, Ltd.). The width of the partition wall at the contact portion between the partition wall and the substrate can be measured as L2. When there was a radiation shielding layer between the partition wall and the substrate, the width of the partition wall at the contact portion between the partition wall and the shielding layer was measured as L2. Moreover, the width | variety of the top part of a partition can be measured as L1. If the top of the partition wall is rounded or the bottom of the partition wall is skirted and it is difficult to accurately grasp the top of the partition wall or the bottom of the partition wall, the height is 90% instead of L1. Instead of the width (L90) and L2, a 10% height width (L10) may be measured and substituted. Note that L90 is the line width of the portion at a height of 90 from the partition wall bottom surface when H1 is 100, and L10 is the line width of the portion of the portion from the partition wall bottom surface when H1 is 100.

  A scintillator panel can be completed by filling the cells partitioned by the partition walls with a phosphor. Here, the cell refers to a space partitioned by grid-like or stripe-like partition walls. The phosphor filled in the cell is called a scintillator layer.

Various known radiation phosphor materials can be used as the phosphor. In particular, the conversion from the radiation to visible light is _{high, 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 or 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.

  For forming the scintillator layer, for example, a method of vapor-depositing crystalline CsI (in this case, a thallium compound such as thallium bromide can be co-evaporated) by vacuum deposition, a phosphor slurry dispersed in water is used as a substrate. The phosphor paste prepared by mixing phosphor powder, an organic resin binder such as ethyl cellulose or acrylic resin, and an organic solvent such as terpineol or γ-butyrolactone is screen-printed or dispenser. The method of applying by is preferable.

  The volume of the phosphor filled in the cells partitioned by the partition walls is preferably 50 to 100% in the volume fraction occupied by the phosphor. If the volume fraction occupied by the phosphor is less than 50%, incident radiation cannot be efficiently converted into visible light. In order to increase the conversion efficiency of incident radiation, it is possible to improve the efficiency of conversion to visible light by increasing the aspect ratio of the partition height to the partition pitch, but it is possible to increase the density of the cell space. Filling the phosphor is preferable because the efficiency can be further increased.

  The adhesive layer that may be formed between the partition and the scintillator layer of the scintillator panel and the photodetector can be formed of, for example, a transparent adhesive made of a thermosetting or ultraviolet curable resin. As such a transparent adhesive, a transparent adhesive made of an acrylic resin, an epoxy resin, a polyester resin, a butyral resin, a polyamide resin, or an ethyl cellulose resin is more preferable, but the adhesive layer may be formed of a low softening point glass. . Further, in order to suppress light scattering at the interface to the minimum and efficiently guide the emitted light of the phosphor to the photoelectric conversion layer to improve the luminance, the difference in average refractive index between the phosphor and the adhesive layer is 0. Is preferably less than .5. Here, when the phosphor is made of a single material, the average refractive index means the refractive index of the material. Moreover, when a fluorescent substance consists of multiple types of materials, the weighted average value of each refractive index is said.

  For the photoelectric conversion layer, for example, a photo detector such as a photomultiplier tube, a photodiode, or a PIN photodiode is formed as a pixel on an insulating substrate such as a glass substrate, a ceramic substrate, or a resin substrate, and a thin film transistor (TFT: Thin) is formed. It can be constituted by a switching element made of a film transistor.

Since the emitted light of the phosphor can be efficiently guided to the photoelectric conversion layer, the average refractive index of the organic resin binder of the scintillator layer is λ1, the average refractive index of the photoelectric conversion layer is λ2, and the average refractive index of the adhesive layer is If λ3,
λ1 ≦ λ3 ≦ λ2
It is preferable to satisfy the relationship.

  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 mass% solution Organic resin binder: Ethyl cellulose (manufactured by Hercules)
Viscosity modifier: Flownon EC121 (manufactured by Kyoeisha Chemical Co., Ltd.)
Solvent: γ-butyrolactone low melting glass powder:
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., thermal expansion coefficient 70 × 10 ⁻⁷ , average particle diameter 2.3 μm
(Preparation of photosensitive paste 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 photopolymerization initiator, 0.2 parts by weight of polymerization inhibitor and 12 8 parts by mass of the UV absorber solution was dissolved in 38 parts by mass of solvent at a temperature of 80 ° C. After cooling the obtained solution, 9 parts by mass of a viscosity modifier was added to prepare an organic solution 1. The refractive index (ng) of the organic coating film obtained by applying and drying the organic solution on the glass substrate was 1.555.

  Next, after adding 30 parts by mass of the low melting glass powder and 10 parts by mass of the high melting point glass powder to 60 parts by mass of the organic solution 1, the mixture is kneaded with a three-roller kneader to produce a photosensitive paste for partition walls. Produced.

(Preparation of base paste)
40 parts by mass of terpineol solution (containing 10% by mass of ethylcellulose), 15 parts by mass of dipentaerythritol hexaacrylate, 1 part by mass of azobisisobutyronitrile, 40 parts by mass of low melting point glass powder The same material as the adhesive paste) and 4 parts by mass of titanium oxide powder were mixed and kneaded to prepare a thermosetting base paste.
(Preparation of reflective layer paste)
20 parts by weight of ethylcellulose powder and 80 parts by weight of benzyl alcohol resin were mixed and heated and stirred at 80 ° C. for 4 hours to prepare a 20% by weight binder resin solution.

Next, 20 parts by weight of aluminum powder (average particle size: 3.0 μm), 20 parts by weight of titanium oxide powder (average particle size: 0.3 μm), 5 parts by weight of dispersant (manufactured by Kyoeisha Chemical Co., Ltd.), 35 parts by weight Of terpineol was dispersed to obtain a slurry solution. 20 parts by weight of the above binder resin solution was mixed and kneaded to prepare a reflective layer paste.
(Photodetector)
Pixel size 125 μm × consisting of a PIN photodiode made of amorphous silicon with a refractive index of 3.5 and a TFT on a 500 mm × 500 mm × 0.5 mm thick glass substrate (manufactured by AGC Asahi Glass; AN-100) A plurality of 125 μm photoelectric conversion layers were formed in a matrix. Next, a wiring portion made of AL such as a bias wiring for applying a bias to the PIN photodiode, a driving wiring for applying a driving signal to the TFT, and a signal wiring for outputting a signal charge transferred by the TFT is formed. A photodetector was fabricated.

Example 1
The substrate paste was applied with a 15 μm bar coater on a 500 mm × 500 mm × 0.5 mm thick glass substrate (manufactured by AGC Asahi Glass Co., Ltd .; AN-100), dried and heat-cured at 150 ° C. for 30 minutes, A 12 μm base paste film was formed. Next, the barrier rib photosensitive paste was applied with a die coater so that the thickness after drying was 500 μm, and dried at 120 ° C. for 30 minutes to form a first barrier rib photosensitive paste coating film. .

Next, the photosensitive paste coating film for the first partition is formed through a photomask (a chrome mask having a stripe opening with a pitch of 250 μm and a line width of 8 μm) in which openings corresponding to a desired auxiliary partition pattern are formed. It exposed at 700 mJ / cm < ² > with the ultra high pressure mercury lamp.

  On the exposed photosensitive paste coating film of the first layer, the same photosensitive paste for partition walls as that of the first layer is applied with a die coater so that the thickness after drying is 100 μm, and then dried at 120 ° C. for 30 minutes. Then, a second-layer photosensitive paste coating film for the partition was formed.

Next, a photomask (a chrome mask having a stripe opening with a pitch of 125 μm and a line width of 8 μm) in which openings corresponding to a desired main barrier rib pattern are formed is perpendicular to the auxiliary barrier rib pattern formed in the first layer. Then, the first-layer barrier rib photosensitive paste coating film and the second-layer barrier rib photosensitive paste coating film were simultaneously exposed to 800 mJ / cm ² with an ultrahigh pressure 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 grid-like photosensitive paste coating film pattern for barrier ribs. Further, the photosensitive paste coating film pattern for barrier ribs was baked in the air at 585 ° C. for 15 minutes, and on the surface, P1 was 125 μm, L1 was 10 μm, L2 was 20 μm, H1 was 400 μm, P2 was 250 μm, A substrate having a grid-like partition wall having a size of 480 mm × 480 mm formed of auxiliary partition walls having L1 of 9 μm, L2 of 20 μm, and H2 of 320 μm was produced.

  Next, an aluminum reflective layer was formed on the entire surfaces of the main partition walls and the auxiliary partition walls using a batch type sputtering apparatus (manufactured by ULVAC; SV-9045). The thickness of the aluminum reflective layer near the top of the main partition wall was set to 300 nm.

Next, gadolinium oxysulfide powder Gd ₂ O ₂ S (Gd ₂ O ₂ S: Tb) having a particle size of 6 μm and a refractive index of 2.2 is mixed with ethyl cellulose having a refractive index of 1.5, and then partitioned by main partition walls. A scintillator panel with a phosphor filling rate of 98% was prepared.

  Next, after forming an adhesive layer made of a hot-melt resin having a thickness of 10 μm on the scintillator panel, the main partition of the scintillator panel is the photoelectric detector of the photodetector while the scintillator panel is not curved. The adhesive layer on the scintillator panel was overlaid so as to be positioned between the conversion layers. In this way, with the scintillator panel and the photodetector overlapped with each other through the adhesive layer, heating and evacuation is performed with a 120 ° C. vacuum press device, air bubbles in the adhesive layer are removed, and cooling to room temperature is performed. The layer was cured to produce a radiation detector. The average refractive index of the formed adhesive layer was 1.6.

  Next, X-rays having a voltage of 80 kVp are irradiated from the back surface of the photodetector (the surface on which the photoelectric conversion layer is not formed), and the amount of light emitted from the scintillator layer after passing through the photoelectric conversion layer is converted into the photoelectric conversion layer. Detection and measurement were performed at, and the measured value was defined as luminance. Further, X-ray image data obtained by detection with the photoelectric conversion layer was analyzed by a computer, and the sharpness of the obtained X-ray image was calculated. These values were expressed as relative values when the solid phosphor film without barrier ribs (corresponding to the scintillator panel produced in Comparative Example 3) was taken as 100. As a result, the luminance was 96 and the sharpness was 153, both of which were good values.

(Example 2)
In the same manner as in Example 1, a base paste film and a first-layer photosensitive paste coating film for partition walls were formed on a glass substrate.

  Next, it exposed on the same conditions as Example 1 through the photomask (Chrome mask which has a stripe opening part with a pitch of 360 micrometers and line | wire width of 13 micrometers) in which the opening part corresponding to a desired auxiliary | assistant partition wall pattern was formed. On the exposed first-layer photosensitive paste coating film, a second-layer photosensitive paste coating film for barrier ribs was formed in the same manner as in Example 1.

  Next, a photomask having openings corresponding to a desired main partition wall pattern (a photomask having stripe openings with a line width of 8 μm in which pitches of 110 μm and 130 μm are alternately repeated) is the same as in the first embodiment. Then, the film was arranged perpendicular to the auxiliary barrier rib pattern, exposed and developed to form a grid-like photosensitive paste coating film pattern. Further, the photosensitive paste coating film pattern was baked in air at 595 ° C. for 15 minutes, and P1 was 110 μm and 130 μm, L1 was 10 μm, L2 was 20 μm, H1 was 380 μm on the surface, P2 was 360 μm, A substrate having a grid-like partition wall having a size of 480 mm × 480 mm formed of auxiliary partitions having L1 of 15 μm, L2 of 24, and H1 of 300 μm was produced.

  Next, the paste for the reflective layer was dispensed and then dried at 160 ° C. for 20 minutes. Thereafter, the reflective layer paste adhered to the top of the partition wall was removed while observing under a microscope using an adhesive tape (manufactured by Sumitomo 3M Limited).

  Next, a scintillator panel was prepared by filling the phosphor with the same method as in Example 1, and was superimposed on a photodetector to produce a radiation detection apparatus.

  When this radiation detection apparatus was evaluated by the same method as in Example 1, the luminance was 98 and the sharpness was 133, both of which were good values.

(Comparative Example 1)
In the same manner as in Example 1, a base paste film and a first-layer partitioning photosensitive paste coating film were formed on a glass substrate.

  Next, it exposed on the same conditions as Example 1 through the photomask (Chrome mask which has a stripe opening part with a pitch of 100 micrometers and a line width of 10 micrometers) in which the opening part corresponding to a desired auxiliary | assistant partition wall pattern was formed. On the exposed first-layer photosensitive paste coating film, a second-layer photosensitive paste coating film for barrier ribs was formed in the same manner as in Example 1.

  Thereafter, exposure, development, and baking are performed in the same manner as in Example 1, and P1 is 125 μm, L1 is 10 μm, L2 is 20 μm, L1 is 400 μm on the surface, P2 is 100 μm, L1 is 13 μm, and L2 A substrate having a grid-like partition wall having a size of 480 mm × 480 mm formed of auxiliary partition walls having a thickness of 24 μm and L1 of 320 μm was prepared.

  Next, the reflection layer was formed and the phosphor was filled in the same manner as in Example 1 to produce a scintillator panel, which was superposed on the photodetector to produce a radiation detection apparatus.

  When this radiation detection apparatus was evaluated by the same method as in Example 1, the luminance was 56 and the sharpness was 76, and significant deterioration occurred.

(Comparative Example 2)
After the base paste film and the first-layer barrier rib photosensitive paste coating film were formed on the glass substrate by the same method as in Example 1, the second-layer barrier rib was formed in the same manner as in Example 1 without exposure. A photosensitive paste coating film was formed.

  Next, it exposed on the same conditions as Example 1 through the photomask (The photomask which has a stripe opening part with a pitch of 125 micrometers and line | wire width of 8 micrometers) in which the opening part corresponding to a desired partition pattern was formed.

  Thereafter, development and baking are performed in the same manner as in Example 1, and P1 is 125 μm, L1 is 10 μm, L2 is 20 μm, L1 is 400 μm, and a stripe-shaped main partition wall having a size of 480 mm × 480 mm is formed on the surface. A substrate was prepared. However, meandering was partially generated in the main partition wall, and there were some places where the partition wall was inclined.

  Next, in the same manner as in Example 1, a scintillator panel was produced by forming a reflective layer and filling a phosphor, and was superimposed on a photodetector to produce a radiation detection apparatus.

  When this radiation detection apparatus was evaluated by the same method as in Example 1, the luminance was 67 and the sharpness was 65 at a location where the main partition wall was distorted, and a significant deterioration occurred.

(Comparative Example 3)
A radiation detection apparatus was produced in the same manner as in Example 1, except that the barrier ribs were not formed on the scintillator panel and a phosphor solid film was formed.

  From the above evaluation results, it can be seen that the radiation detection apparatus using the scintillator panel of the present invention has high emission luminance and can realize a high-definition image.

DESCRIPTION OF SYMBOLS 1 Radiation detection apparatus 2 Scintillator panel 3 Photo detector 4 Scintillator panel side board | substrate 5 Radiation shielding layer 6A Main partition wall 6B Auxiliary partition wall 7 Phosphor (scintillator layer)
8 Reflective layer 9 Photoelectric conversion layer 10 Photodetector side substrate 11 Adhesive layer

  The present invention can be usefully used as a scintillator panel used in a radiation detection apparatus used in a medical diagnostic apparatus, a nondestructive inspection instrument, and the like.

Claims (4)

A flat substrate, a plurality of main barrier ribs formed in parallel on the substrate, an auxiliary barrier rib formed perpendicular to the main barrier rib, and a cell partitioned by the main barrier rib are filled A scintillator panel made of phosphor,
The pitch P1 of the main partition walls and the pitch P2 of the auxiliary partition walls are
P1 <P2
The height H1 of the main partition wall and the height H2 of the auxiliary partition wall are
H1> H2
A scintillator panel that satisfies this relationship. The H1 and the H2 are
H1 × 0.5 ≦ H2 ≦ H1 × 0.9
It satisfies the relationship, according to claim 1 scintillator panel according. The scintillator panel according to claim 1 or 2 , wherein a reflective layer is formed on a surface of the main partition wall. The scintillator panel according to any one of claims 1 to 3 , wherein the main partition wall and the auxiliary partition wall are made of a material mainly composed of low melting point glass containing 2 to 20% by mass of an alkali metal oxide. .

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