JP2018036198A - Scintillator panel - Google Patents

Abstract

Provided is a scintillator panel in which adhesion between an undercoat layer and a scintillator layer is promoted and film peeling is suppressed. At least one scintillator layer for converting radiation into visible light, a reflective layer for reflecting the visible light converted by the scintillator layer, and at least one layer among the scintillator layers are provided. An undercoat layer in contact with a scintillator layer in a region, wherein the undercoat layer contains a metal compound, and in the undercoat layer, the amount of the metal compound is distributed, and in the image forming region. A scintillator panel characterized in that the atomic% of the metal element on the surface of the undercoat layer in contact with the scintillator layer is smaller than the atomic% of the metal element in other parts of the undercoat layer. [Selection diagram] Fig. 1

Description

  The present invention relates to a scintillator panel having a scintillator layer having excellent adhesion.

  In recent years, digital radiographic image detectors such as computed radiography (CR) and flat panel detectors (FPD) have been capable of directly obtaining digital radiographic images, and cathode tubes. Since it is possible to directly display an image on an image display device such as a liquid crystal panel, it is widely used for image diagnosis in hospitals and clinics. Recently, a flat panel using a scintillator layer containing cesium iodide (CsI) and combined with a thin film transistor (TFT) has attracted attention as a highly sensitive X-ray image visualization system.

  Such a scintillator layer is provided with an undercoat layer (for example, a metal reflective layer) that reflects the light converted by the phosphor in the scintillator layer to the sensor panel side, thereby reducing the loss of emitted light and emitting light. Attempts have been made to obtain scintillators with excellent brightness.

  Such an undercoat layer is usually composed of an inorganic substance. However, since the inorganic substance is highly rigid, if the phosphor is vapor-deposited on such a substance, the scintillator may peel off. Concerned.

  For this reason, it has been desired to promote adhesion for preventing film peeling, but a useful technique for promoting adhesion when a scintillator layer is formed on a highly rigid inorganic substance is completely known. It wasn't.

  Patent Document 1 (Japanese Patent Laid-Open No. 2012-168010), Patent Document 2 (Japanese Patent Laid-Open No. 2014-55977), and Patent Document 3 (Japanese Patent Laid-Open No. 2008-51783) vary the concentration of the activator locally. Patent Document 4 (Japanese Patent Application Laid-Open No. 2010-165916) limits the semiconductor impurity concentration on the sensor side, but does not affect the adhesion between the undercoat layer and the scintillator layer. It doesn't suggest anything.

JP 2012-168010 A JP 2014-055977 JP 2008-051783 A JP 2015-001397

  An object of the present invention is to provide a scintillator panel in which adhesion between the undercoat layer and the scintillator layer is promoted and film peeling is suppressed.

  Under such circumstances, the present inventors have intensively studied and, as a result, in order to promote adhesion, considered the mutual diffusion of the components of the undercoat layer and the scintillator layer and the influence of organic impurities on the surface of the undercoat layer.

  And it discovered that the said subject could be solved by reducing the atomic percentage of the undercoat layer outermost surface (surface which touches a scintillator), and came to complete this invention. The configuration of the present invention is as follows.

[1] At least
A scintillator layer that converts radiation into visible light;
A reflective layer that reflects visible light converted by the scintillator layer;
An undercoat layer present between the scintillator layer and the reflective layer, at least one of which is in contact with the scintillator layer in the image forming region;
A scintillator panel comprising
The undercoat layer contains a metal compound, the amount of the metal compound is distributed in the undercoat layer, and the atomic percentage of metal elements on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is the undercoat layer. A scintillator panel characterized by being smaller than the atomic percentage of metal elements in other parts of the layer.
[2] The scintillator panel according to [1], wherein the metal compound is a metal oxide.
[3] In the scintillator panel, at least one atomic% of substances that become a gas at normal temperature and pressure on the surface of the undercoat layer that contacts the scintillator layer in the image forming region is 0.1% or more. The scintillator panel according to [1] or [2], which is characterized.
[4] The scintillator according to any one of [1] to [3], wherein, in the scintillator panel, an undercoat layer in contact with the scintillator layer in the image forming region is made of only a metal oxide. panel.
[5] The scintillator panel according to [4], wherein in the scintillator panel, the atomic percentage of carbon on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is 0.1% or less.
[6] The scintillator panel according to any one of [1] to [5], wherein the scintillator layer does not contain a binder resin.
[7] The scintillator panel according to [6], wherein the scintillator layer is made of physical vapor deposition.
[8] The scintillator panel according to [7], wherein the scintillator layer contains cesium iodide as a main component.

  The scintillator panel of the present invention is characterized in that the atomic percentage of the metal element on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is smaller than the atomic percentage of the metal element in other portions of the undercoat layer. As a result, the interface adhesion between the undercoat layer and the cinch layer is improved, and even if the undercoat layer is made of a highly rigid material such as an inorganic material, film peeling does not occur and image deterioration can be suppressed.

It is a schematic cross section which shows the radiation detector which concerns on this invention. It is the schematic of the vapor deposition apparatus at the time of scintillator layer formation.

The scintillator panel of the present invention includes a scintillator layer that converts radiation into visible light,
A reflective layer for emitting light by the scintillator layer;
Between the scintillator layer and the reflective layer, at least one layer includes an undercoat layer in contact with the scintillator layer in the image forming region.

A basic configuration of such a radiation detector according to the present invention is shown in FIG.
As shown in FIG. 1, the scintillator panel according to the present invention has an undercoat layer between the scintillator layer and the reflective layer, and the amount of the metal compound is distributed in the undercoat layer, and the image forming area Thus, the atomic percentage of the metal element on the surface of the undercoat layer in contact with the scintillator layer is less than the atomic percentage of the metal element on the surface of the undercoat layer compared to other portions of the undercoat layer.

By reducing the number of atoms of the metal element on the surface of the undercoat layer in contact with the scintillator layer in this way, the components mutually diffuse between the scintillator layer and the undercoat layer, and the interfacial adhesion between the undercoat layer and the scintillation layer Even if the undercoat layer is made of a highly rigid material such as an inorganic material, film peeling does not occur and image deterioration can be suppressed.
Hereinafter, each component will be described in order.

The scintillator layer The scintillator layer is made of a phosphor and has a role of converting X-ray energy, which is radiation incident from the outside, into visible light.

  In the present invention, the term “phosphor” refers to a phosphor that emits light when atoms are excited when it is irradiated with ionizing radiation such as α-rays, γ-rays, and X-rays. That is, it refers to a phosphor that converts radiation into visible light and emits it. The phosphor is not particularly limited as long as it is a material that can efficiently convert radiation energy such as X-rays incident from the outside into light. Further, the conversion of radiation into light is not necessarily performed instantaneously, and a method of temporarily storing a latent image in the scintillator layer and reading it out later may be used.

  As the scintillator according to the present invention, a substance capable of converting radiation such as X-rays into different wavelengths such as visible light can be appropriately used. Specifically, scintillators and phosphors described on pages 284 to 299 of “Phosphor Handbook” (Edited by Fluorescent Materials Association, Ohmsha, 1987), and the website of Lawrence Berkeley National Laboratory, USA Although the substances described in “Scintillation Properties (http://scintillator.lbl.gov/)” can be considered, even if the substance is not pointed out here, “radiation such as X-rays is converted into different wavelengths such as visible light” Any substance that can be used can be used as a scintillator.

Specific examples of the scintillator composition include the following examples. First,
Basic composition formula (I): M _I X · aM _II X ′ ₂ · bM _III X ″ ₃ : zA
And metal halide phosphors represented by the formula:

In the basic composition formula (I), M _I is an element that can be a monovalent cation, that is, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), thallium. It represents at least one selected from the group consisting of (Tl) and silver (Ag).

M _II is an element that can be a divalent cation, that is, beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), nickel (Ni), copper (Cu), It represents at least one selected from the group consisting of zinc (Zn) and cadmium (Cd).

M _III represents at least one selected from the group consisting of scandium (Sc), yttrium (Y), aluminum (Al), gallium (Ga), indium (In), and elements belonging to lanthanoids.

X, X ′, and X ″ each represent a halogen element, but each may be a different element or the same element.
A is composed of Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Na, Mg, Cu, Ag (silver), Tl and Bi (bismuth). Represents at least one element selected from the group;

a, b and z each independently represent a numerical value within the range of 0 ≦ a <0.5, 0 ≦ b <0.5, and 0 <z <1.0.
Also,
Also included are rare earth activated metal fluorohalide phosphors represented by the basic composition formula (II): M _II FX: zLn.

In the basic composition formula (II), M _II represents at least one alkaline earth metal element, Ln represents at least one element belonging to the lanthanoid, and X represents at least one halogen element. Z is 0 <z ≦ 0.2.

Also,
Basic composition formula (III): Ln ₂ O ₂ S: zA
And rare earth oxysulfide phosphors.

  In the basic composition formula (III), Ln is at least one element belonging to the lanthanoid, A is Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, At least one element selected from the group consisting of Lu, Na, Mg, Cu, Ag (silver), Tl and Bi (bismuth) is represented. Z is 0 <z <1.

In particular, Gd ₂ O ₂ S using gadolinium (Gd) as Ln emits high light in a wavelength region where the sensor panel is most likely to receive light by using terbium (Tb), dysprosium (Dy), etc. as the element species of A. This is preferred because it is known to exhibit properties.

Also,
Basic formula _{(IV): M II S:} zA
The metal sulfide type fluorescent substance represented by these is also mentioned.

In the basic composition formula (IV), M _II is selected from the group consisting of elements that can be divalent cations, ie, alkaline earth metals, Zn (zinc), Sr (strontium), Ga (gallium), and the like. At least one element, A is Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Na, Mg, Cu, Ag (silver), Tl And at least one element selected from the group consisting of Bi (bismuth). Z is 0 <z <1.

Also,
Basic composition formula (V): M _IIa (AG) _b : zA
And metal oxoacid salt phosphors represented by the formula:

In the basic composition formula (V), _MII is a metal element that can be a cation, and (AG) is a group consisting of phosphate, borate, silicate, sulfate, tungstate, and aluminate. At least one oxo acid group selected from the group consisting of A, Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Na, Mg, Cu, Each represents at least one element selected from the group consisting of Ag (silver), Tl, and Bi (bismuth).

A and b represent all possible values depending on the valence of the metal and oxo acid group. z is 0 <z <1.
Also,
Basic composition formula (VI): M _a O _b : zA
The metal oxide fluorescent substance represented by these is mentioned.

In the basic composition formula (VI), M represents at least one element selected from metal elements that can be cations.
A is composed of Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Na, Mg, Cu, Ag (silver), Tl and Bi (bismuth). Each represents at least one element selected from the group.

A and b represent all possible values depending on the valence of the metal and oxo acid group. z is 0 <z <1.
In addition,
Basic composition formula (VII): LnOX: zA
And metal acid halide phosphors represented by the formula:

  In the basic composition formula (VII), Ln represents at least one element belonging to the lanthanoid, X represents at least one halogen element, A represents Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb. , Dy, Ho, Er, Tm, Yb, Lu, Na, Mg, Cu, Ag (silver), Tl, and Bi (bismuth), each represents at least one element. Z is 0 <z <1.

  The material constituting the scintillator is not particularly limited as long as it can efficiently convert X-ray energy incident from the outside into light. Therefore, as long as the above conditions are satisfied, various conventionally known phosphors can be used as the scintillator. Among them, cesium iodide (CsI), gadolinium sulfate (GOS), cadmium tungstate (CWO), gadolinium silicate, and the like. (GSO), bismuth germanate (BGO), lutetium silicate (LGO), lead tungstate (PWO) and the like can be suitably used. Note that the scintillator used in the present invention is not limited to an instantaneous light emitting phosphor such as CsI, and may be a stimulable phosphor such as cesium bromide (CsBr) depending on applications.

  In the present invention, among these materials, CsI has a relatively high efficiency in converting the energy of radiation such as X-rays into visible light, and the light reflection at a specific wavelength as described above by combination with an activator. It is preferable because a scintillator with a small decrease in rate can be configured. In the present invention, it is preferable that CsI is used as a phosphor base material and an activator is included together with this. The concentration of the activator is shown in mol%.

As the activator, those containing thallium (Tl), europium (Eu), indium (In), lithium (Li), potassium (K), rubidium (Rb), sodium (Na) and the like are preferable. These activators are present in the scintillator in the elemental state. As the activator, for example, thallium iodide (TlI), thallium bromide (TlBr), thallium chloride (TlCl), thallium fluoride (TlF, TlF ₃ ) or the like is used.

  The activator contained in the scintillator preferably contains at least thallium. When thallium is included, the wavelength of fluorescence when irradiated with X-rays is not shifted, the accuracy of fluorescence detection by the photoelectric conversion element is high, and the decrease in light reflectance after radiation irradiation at 520 nm is reduced. Therefore, it is possible to obtain a scintillator that satisfies the predetermined light reflectance defined in the present invention.

  In the present invention, the scintillator layer may be composed of one layer or may be composed of two or more layers. The scintillator layer may be composed of only a base layer or a scintillator layer, and the base layer and the scintillator layer are laminated in this order on the support. Also good. When the scintillator layer includes two layers of an underlayer and a scintillator layer, these layers may be made of the same material or different materials as long as the phosphor base material compound is the same. There may be. That is, the scintillator layer may be a single layer consisting entirely of the phosphor base material, or may be a single layer containing the phosphor base material compound and the activator, and only the phosphor base compound. And a scintillator layer containing a phosphor base material compound and an activator, a base layer containing a phosphor base material compound and a first activator, and a phosphor base It may consist of a scintillator layer containing a material compound and a second activator.

  In the scintillator layer according to the present invention, it is desirable that the relative content of the activator is an optimal amount depending on the target performance and the like, but 0.001 mol% to 50 mol% with respect to the scintillator content, It is preferable that it is 0.1-10.0 mol%. When the concentration of the activator is 0.001 mol% or more with respect to the scintillator, the emission luminance is improved more than when the scintillator is used alone, and this is preferable in terms of obtaining the target emission luminance. Moreover, it is preferable that it is 50 mol% or less because scintillator properties and functions can be maintained.

  The relative content of the activator in the underlayer is preferably from 0.01 to 1 mol%, more preferably from 0.1 to 0.7 mol%. In particular, the relative content of the activator in the underlayer is preferably 0.01 mol% or more from the viewpoint of improving the light emission luminance and storage stability of the scintillator panel 10. Further, it is very preferable that the relative content of the activator in the underlayer is lower than the relative content in the scintillator layer, and the molar ratio of the relative content of the activator in the underlayer to the relative content of the activator in the scintillator layer ( (Relative content of activator in underlayer) / (relative content in scintillator layer)) is preferably 0.1 to 0.7.

  As a method of forming the scintillator layer, a method of forming a coating film by applying a liquid obtained by mixing scintillator powder with a binder resin or the like, or a regular arrangement structure by processing the liquid or the coating film. It is possible to use a method of forming a film having a crystal film, a method of forming a crystal film using various vapor deposition methods, or the like. Examples of the binder resin include proteins such as gelatin, polysaccharides such as dextran, or natural polymer substances such as gum arabic; and polyvinyl butyral, polyvinyl acetate, nitrocellulose, ethyl cellulose, vinylidene chloride / vinyl chloride copolymer, Examples include synthetic polymer materials such as poly (meth) acrylate, vinyl chloride / vinyl acetate copolymer, polyurethane, cellulose acetate butyrate, polyvinyl alcohol, polyester, epoxy resin, polyolefin resin, polyamide resin, and the like.

  Examples of the vapor deposition method include a physical vapor deposition (PVD) method and a chemical vapor deposition (CVD) method. The PVD method includes methods such as heat deposition, sputtering, and ion plating. In the CVD method, a raw material gas is reacted to form a thin film. In plasma CVD, which is one of the CVD methods, a gas is converted into plasma with electromagnetic energy to create a scintillator layer. It is also possible to form a scintillator layer by attaching a crystal formed in a sheet shape. According to such a vapor deposition method, a columnar crystal scintillator layer can be formed.

  In the present invention, it is preferable that the scintillator layer does not contain a binder resin. For this reason, what was formed by the vapor deposition method is more preferable than what was formed by the coating which mixed scintillator powder with binder resin etc. Including a binder may affect the amount of carbon on the surface of the undercoat layer, and may affect the adhesion of the undercoat layer.

  Furthermore, in the present invention, the scintillator layer is preferably a physical vapor deposition. By defining the number of metal atoms on the surface of the undercoat layer relative to the physical vapor deposit, it is possible to suppress peeling at the interface with the scintillator layer and to further improve the adhesion. Thereby, deterioration of an image can be suppressed.

For this reason, it is preferable that the scintillator layer is not attached with a sheet-like crystal or CVD film formation. In the case of physical vapor deposition, the scintillator layer is preferably composed mainly of CsI.
In addition, it is preferable that the thickness of a scintillator layer is 100-800 micrometers, and it is more preferable that it is 120-700 micrometers from the point from which the characteristic of a brightness | luminance and sharpness is acquired with sufficient balance. The layer thickness of the underlayer is preferably 0.1 μm to 50 μm, more preferably 5 μm to 40 μm from the viewpoint of maintaining high brightness and sharpness.

Support In the scintillator panel according to the present invention, a support is not always necessary. The support is used as a base of the phosphor forming the scintillator layer and has a role of maintaining the structure of the scintillator layer. Examples of the material for the support include various glasses, polymer materials, metals, and the like. In the final scintillator panel, the support may be detached.

Specifically, plate glass such as quartz, borosilicate glass, chemically tempered glass; ceramics such as sapphire, silicon nitride, silicon carbide; semiconductors such as silicon, germanium, gallium arsenide, gallium phosphorus, gallium nitrogen; cellulose acetate film, Polymer films (plastic film) such as polyester film, polyethylene terephthalate film, polyamide film, polyimide film, triacetate film, polycarbonate film, carbon fiber reinforced resin sheet;
A metal sheet such as an aluminum sheet, an iron sheet, or a copper sheet, or a metal sheet having a coating layer of an oxide of these metals; These may be used alone or in a stacked manner.

Among the materials for the support, a flexible polymer film is preferable.
Such polymer films include polyethylene terephthalate, polyethylene naphthalate, cellulose acetate, polyamide, polyimide, polyetherimide, epoxy, polyamideimide, bismaleimide, fluororesin, acrylic, polyurethane, aramid, nylon, polycarbonate, polyphenylene sulfide. And a film made of polyethersulfone, polysulfone, polyetheretherketone, liquid crystal polymer, bionanofiber and the like.

  When vapor-depositing the phosphor on the resin film, a resin film containing polyimide is preferable from the viewpoint of heat resistance. As a commercially available product, for example, UPILEX-125S (manufactured by Ube Industries) may be used.

  The thickness of the polymer film is preferably 20 to 1000 μm, more preferably 50 to 750 μm. By making the thickness of the support 50 μm or more, the handling property after forming the scintillator layer is improved. Moreover, by making the thickness of the support 750 μm or less, functional layers such as an adhesion layer, a conductive layer, and an easy-adhesion layer can be easily processed by roll-to-roll, and productivity is improved. From the viewpoint of improvement, it is very useful.

  The support may be detached or left as it is. When it is used as it is, it is desirable that it is made of a transparent material.

Reflective layer In the present invention, a reflective layer is provided to reflect light emitted by the scintillator layer. By reflecting the emitted light, the light emitted from the scintillator is efficiently guided to the sensor and the sensitivity is improved.

  The reflective layer is preferably made of a material having a high light reflectivity, and is usually composed of a metal reflective layer. Specific examples of metal materials that can form such a metal reflective layer include metal materials such as aluminum, silver, platinum, palladium, gold, copper, iron, nickel, chromium, cobalt, magnesium, titanium, rhodium, and stainless steel. It is preferable. Among these, silver or aluminum is particularly preferable from the viewpoint of reflectivity. Here, the metal material which comprises a metal reflective layer has the form of the metal single-piece | unit or its alloy in the typical aspect of this invention.

However, as long as the light scattering does not increase, it is not necessarily limited to those having a single metal form or an alloy thereof, and may be a corresponding metal oxide form. In this case, a so-called dielectric multilayer film that has a reflection function by stacking a plurality of thin films of metal oxides can be assumed. As a suitable example of the metal oxide used for such a dielectric multilayer film, aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), niobium oxide (Nb ₂ O ₅ ) And tantalum oxide (Ta ₂ O ₅ ).

  An organic material can also be used as the dielectric layer. The organic material layer preferably contains a polymer binder (binder), a dispersant and the like. The refractive index of the organic material layer is approximately in the range of 1.4 to 1.6 depending on the type of material. The thickness of the organic material layer is preferably 0.5 to 4 μm. When the thickness is 4 μm or less, light scattering in the organic material layer is reduced and sharpness is improved. Moreover, the effect as a reflection layer becomes large because the thickness of an organic material layer shall be 0.5 micrometer or more. Specific examples of the polymer binder used in the organic material layer include polyurethane, vinyl chloride copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer. Polymer, butadiene-acrylonitrile copolymer, polyamide resin, polyvinyl butyral, polyester, cellulose derivative (nitrocellulose, etc.), styrene-butadiene copolymer, various synthetic rubber resins, phenol resin, epoxy resin, urea resin, melamine resin , Phenoxy resin, silicone resin, acrylic resin, urea formamide resin, and the like.

  As a method of providing the metal reflection layer on the support surface, a method using a known process such as vapor deposition or sputtering, or a metal such as aluminum can be formed into a thin film and pasted later. In addition, the metal foil can be pressure-bonded via an adhesive, but if the adhesive is present, light absorption may occur and the amount of light may be reduced. From such a viewpoint, sputtering is preferable. In addition, when taking the form in which the photodetector is present on the support side, it is also possible to provide a metal reflection layer on the opposite side of the support with the scintillator layer interposed therebetween, in which case a thin metal is affixed This is particularly preferable because it is not necessary for the film to be easily cracked by following the unevenness of the scintillator layer, such as a film formed by vapor deposition or sputtering. The organic material layer is preferably formed by applying and drying a polymer binder (hereinafter also referred to as “binder”) dissolved or dispersed in a solvent.

  Further, the reflective layer may be a reflective layer composed of a binder resin and at least one of light scattering particles or voids. As one aspect thereof, a coating-type reflective layer can be mentioned.

  The binder resin may be an easily adhesive polymer such as polyurethane, vinyl chloride copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, butadiene-acrylonitrile. Copolymer, polyamide resin, polyvinyl butyral, polyester, cellulose derivative (nitrocellulose, etc.), styrene-butadiene copolymer, various synthetic rubber resins, phenol resin, epoxy resin, urea resin, melamine resin, phenoxy resin, silicone Examples thereof include resins, acrylic resins, urea formamide resins, and the like.

Among them, it is preferable to use polyurethane, polyester, silicone resin, acrylic resin or polyvinyl butyral. Moreover, these binders can also be used in mixture of 2 or more types.
As the light scattering particles, those made of a white pigment are preferable from the viewpoint of light refraction.

Examples of the white pigment include TiO ₂ (anatase type, rutile type), MgO, PbCO ₃ · Pb (OH) ₂ , BaSO ₄ , Al ₂ O ₃ , M (II) FX (where M (II) is Ba). , Sr and Ca, and X is a Cl atom or a Br atom.), CaCO ₃ , ZnO, Sb ₂ O ₃ , SiO ₂ , ZrO ₂ , lithopone (BaSO _4. ZnS), magnesium silicate, basic silicic acid sulfate, basic lead phosphate, aluminum silicate and the like can be used. These white pigments may be used alone or in combination.

Of these white pigments, TiO ₂ , Al ₂ O _{3 and the} like have a strong hiding power and a high refractive index. For this reason, by reflecting and refracting the diffused light, the scattered light can be returned to the scintillator layer before propagating in the lateral direction. As a result, it is possible not only to increase the obtained luminance but also to effectively return the diffused light, which was the cause of image blurring, to the scintillator layer, and to significantly improve the image quality.

As the crystal structure of titanium oxide, either a rutile type or an anatase type can be used, but a rutile type is preferable from the viewpoint that a difference in refractive index from the resin is large and high luminance can be achieved.
Specific examples of titanium oxide include CR-50, CR-50-2, CR-57, CR-80, CR-90, CR-93, CR-95, and CR-97 manufactured by the hydrochloric acid method. , CR-60-2, CR-63, CR-67, CR-58, CR-58-2, CR-85, R-820, R-830, R-930, R-550 manufactured by the sulfuric acid method , R-630, R-680, R-670, R-580, R-780, R-780-2, R-850, R-855, A-100, A-220, W-10 : Ishihara Sangyo Co., Ltd.).

  The primary particle size of the light scattering particles is preferably in the range of 0.1 to 0.5 μm, more preferably in the range of 0.2 to 0.3 μm. Further, the light scattering particles are particularly preferably those that have been surface-treated with an oxide such as Al, Si, Zr, and Zn in order to improve the affinity and dispersibility with the polymer and to suppress the deterioration of the polymer.

  Further, instead of the light scattering particles, the reflective layer may include voids. Since the light is similarly refracted even in the gap, the return of the diffuse reflected light to the scintillator layer can be increased in the same manner as the light scattering particles.

  As a means for forming a void in the interior, there are various methods such as a method using a foaming agent, a method of lowering pressure by injecting a gas, and a method using stretching. Since the voids are spherical or elliptical, and a large number of fine voids can be formed uniformly, a method of forming voids with a foaming agent is more desirable.

Undercoat layer In the present invention, an undercoat layer is provided between the reflective layer and the scintillator layer. The undercoat layer contains a metal compound. This undercoat layer may be a single layer or a plurality of layers. In the present invention, the metal compound contained in the undercoat layer has a distribution, and the atomic percentage of the metal element on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is the same as that of the metal element in other parts of the undercoat layer. It is characterized by being smaller than the atomic number%. When the atomic number% is defined in this way, the undercoat layer can improve adhesion by mutual diffusion with the scintillator layer.

The atomic% is obtained from the ratio (M ₁ / M ₀ ) of the number of atoms (M ₁ ) and the total number of atoms (M ₀ ) of the metal element. It is smaller than the atomic percentage in other parts of.

  Atom% is secondary ion mass spectrometry (SIMS), time-of-flight secondary ion mass spectrometry (TOF-SIMS), X-ray photoelectron spectrometer (XPS), energy dispersive X analysis (EDS), Auger electron spectroscopy It can be measured by analysis means such as measurement (AES).

  The surface of the undercoat layer in contact with the scintillator layer may be a surface where the scintillator layer is exposed from the scintillator panel having the scintillator layer formed on the surface of the undercoat layer by means such as peeling or grinding, or the scintillator layer. Any of those obtained by evaluating the interface with the scintillator layer as a surface from the cut cross section of the scintillator panel without detaching the layer may be used. In XPS, it is evaluated on the surface where the undercoat layer is exposed, and in EDS and AES, it is evaluated on the cut surface. In TOF-SIMS, a sample is irradiated with an ion beam (primary ions), and ions (secondary ions) emitted from the surface are separated by mass using the time-of-flight difference (the time of flight is proportional to the square root of the weight). It is a method and non-destructive analysis is possible.

The metal compound contained in the undercoat layer may be a metal, a metal oxide, a metal nitride, a composite oxide, a metal salt, or the like.
As the undercoat layer, for example, metal materials such as aluminum, silver, platinum, palladium, gold, copper, iron, nickel, chromium, cobalt, rhodium, magnesium, titanium, stainless steel,
Aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), magnesium oxide (MgO), silicon oxide (SiO ₂ ), niobium oxide (Nb ₂ O ₅ ), tantalum oxide (Ta ₂ O ₅ ), zinc oxide ( ZnO), antimony trioxide (Sb ₂ O ₃ ), zirconium oxide (ZrO ₂ ), zirconium oxide (ZrO ₂ ), hafnium oxide (HfO ₂ ), silver, copper, chromium, cobalt, rhodium used in the above metal materials In addition to metal oxides of elements such as stainless steel, metal fluorides such as lithium fluoride (LiF) and magnesium fluoride (MgF ₂ ), PbCO ₃ · Pb (OH) ₂ , BaSO ₄ , Al ₂ O ₃ , M (II) FX (provided that, M (II) is at least one atom selected from atoms of Ba, Sr and Ca, X is Cl atom or a Br atom.), CaCO _3, lithopone (Ba O ₄ · ZnS), magnesium silicate, basic silicosulfate salts, basic lead phosphate, aluminum silicate, aluminum nitride, silicon nitride, silicon oxynitride, mica, and the like inorganic materials such as talc.

  Among these, a metal oxide is preferable as the metal compound. The subbing layer made of a metal oxide may be formed by PECVD (Plasma Enhanced Chemical Vapor Deposition), thermal evaporation, atomic layer deposition, chemical deposition, or chemical deposition. The above can be formed using methods well known in the art, such as e-beam evaporation.

  In the present invention, the surface of the undercoat layer that is in contact with the scintillator layer in the image forming region contains at least one substance that becomes a gas at normal temperature and pressure, and the atomic percentage is 0.1% or more. Is preferred. Examples of a substance that becomes a gas at normal temperature and pressure include rare gases such as oxygen, nitrogen, argon, helium, and neon. The normal temperature and normal pressure means 1 atmosphere at 300K.

  The surface of the undercoat layer in contact with the scintillator layer is preferably surface-treated. By this surface treatment, the number of metal atoms on the surface of the undercoat layer can be reduced, and a substance that becomes a gas at normal temperature and pressure can be included.

  Examples of the surface treatment include glow discharge, corona discharge, remote plasma treatment, sputter etching treatment, high energy ray (ultraviolet light, electron beam, radiation, laser) irradiation treatment, ozone treatment, and the like.

  The glow discharge treatment is a method called vacuum plasma treatment or low-pressure plasma treatment, and is a method in which plasma is generated by discharge in a gas (plasma gas) in a low-pressure atmosphere to treat the surface. This is performed by placing the object to be processed (support after forming the undercoat layer) in a plasma atmosphere.

  In the glow discharge treatment, methods such as direct current glow discharge, high frequency discharge, and microwave discharge can be used as a method for generating plasma. The power source used for discharging may be direct current or alternating current. When alternating current is used, a range of about 30 Hz to 20 MHz is preferable. Examples of the plasma gas used in the glow discharge treatment include oxygen gas, nitrogen gas, water vapor gas, argon gas, helium gas, neon gas, and xenon gas.

  In the corona treatment, electrons generated by a high frequency high voltage device collide with the surface of the undercoat layer. And the corona discharge process should just process in the atmosphere containing oxygen gas, and may contain nitrogen gas.

Remote plasma treatment is not processing by directly exposing to plasma, but generating plasma at a location different from the location of the substrate to be processed and guiding it to the surface of the substrate to be processed. . As the type of gas, O ₂ , CO ₂ , N ₂ , NH ₃ or the like, water vapor or the like is used.

  The sputter etching process is a surface process by reverse sputtering, and is performed by exposing the surface of the undercoat layer to plasma generated in a reduced pressure atmosphere. The sputtering conditions are not particularly limited, but may be performed in an atmosphere of a rare gas such as argon having a degree of vacuum of 0.075 to 0.1 Torr. As the atmospheric gas for sputter etching, for example, a rare gas such as helium, neon, or argon can be used.

Examples of the high energy beam irradiation treatment include a treatment of irradiating ultraviolet rays, electron beams, radiation, lasers, and the like. At this time, the surface of the undercoat layer is placed in an oxygen atmosphere or a mixed gas atmosphere of sulfur dioxide (SO ₂ ) and oxygen. Furthermore, you may heat-process, performing a high energy ray irradiation process as needed.

Ozone treatment is a method of treating in a gas or aqueous solution containing ozone. The ozone gas treatment is performed using a mixed gas of ozone gas and oxygen gas.
Through the above treatment, metal atoms on the surface are ejected, and a substance that becomes a gas at normal temperature and pressure is ionized and ion-implanted. As a result, the number of atomic percentages on the surface changes, and it is considered that the number is smaller than other parts.

Of these processes, sputter etching is preferred.
For the undercoat layer, in addition to the above metal compound, polyparaxylylene, polyurethane exemplified as a polymer binder (binder), vinyl chloride copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer Polymer, vinyl chloride-acrylonitrile copolymer, butadiene-acrylonitrile copolymer, polyamide resin, polyvinyl butyral, polyester, cellulose derivative (nitrocellulose, etc.), styrene-butadiene copolymer, various synthetic rubber resins, phenol resin An organic material such as an epoxy resin, a urea resin, a melamine resin, a phenoxy resin, a silicone resin, an acrylic resin, or a urea formamide resin may be included.

  “Contacting the scintillator layer in the image forming region” means directly contacting the scintillator layer. In the present invention, the undercoat layer in contact with the scintillator layer in such an image forming region is made of only a metal oxide. It is preferable. By forming the undercoat layer in contact with the scintillator layer in the image forming region from only the metal oxide, the adhesion between the scintillator layer and the undercoat layer can be increased. Note that the undercoat layer that is not in direct contact with the scintillator layer may include materials other than metal oxides.

  Further, it is preferable that the number of carbon atoms in the surface of the undercoat layer in contact with the scintillator layer in the image forming region is 0.1% or less. The atomic percentage of carbon can be measured by the same method as the atomic percentage of metal. As described above, when the number of carbon atoms is adjusted to be within a predetermined range, the adhesion between the scintillator layer and the undercoat layer can be further improved. The carbon component is derived from the undercoat layer such as a support, a scintillator layer, a binder contained in an undercoat layer that does not contact the scintillator layer, or a reflective layer. Such organic impurities on the surface of the undercoat layer can be decomposed and removed by the above-described surface treatment, for example, sputter etching treatment or high energy ray irradiation treatment.

  Further, the thickness of the undercoat layer is preferably 20 to 400 nm. When the thickness is 400 nm or less, light scattering in the undercoat layer is reduced and sharpness is improved. Further, by setting the thickness of the undercoat layer within a predetermined range, it is possible to prevent disturbance in the crystal growth of the phosphor.

Manufacturing method of scintillator panel The scintillator panel according to the present invention is formed by, for example, forming a reflective layer and an undercoat layer in advance on the support, and then performing electrical discharge machining, sputtering, and ultraviolet irradiation treatment, and depositing a phosphor material. It can be manufactured by forming a layer. Such a processing method has already been described.

  A radiation detector is configured by combining the scintillator panel with a photoelectric conversion element array. Such a radiation detector may include at least one intermediate layer existing between the photoelectric conversion element array and the scintillator layer.

  The intermediate layer is composed of at least one layer existing between the photoelectric conversion element array and the scintillator layer. Therefore, the intermediate layer may be a single layer or a plurality of laminates of two or more layers. Furthermore, the intermediate layer may be a plurality of layers having different functions as long as it exists between the photoelectric conversion element array and the scintillator layer. For example, an adhesive layer, a protective layer, an optical coupling layer, and the like can be given. The order of these layers is not particularly limited.

  The adhesive layer joins the scintillator panel and the photoelectric conversion element, and the scintillator layer allows the light emitted from the scintillator layer by irradiation of the radiation to efficiently reach the photoelectric conversion element via the adhesive layer. It is desirable that it is transparent to the emission wavelength. Specifically, the transmittance of the adhesive layer is usually 70% or more, preferably 80% or more, more preferably 90% or more with respect to the emission wavelength of the scintillator layer.

As a material constituting the adhesive layer, for example, a hot melt sheet and a pressure-sensitive adhesive sheet are preferably used.
Here, the hot melt sheet refers to a sheet formed of an adhesive resin (hot melt resin) made of a nonvolatile thermoplastic material that does not contain water or a solvent and is solid at room temperature. The hot melt sheet is inserted between adherends, melted at a temperature equal to or higher than the melting point, and solidified again at a temperature equal to or lower than the melting point, thereby bonding the adherends to each other.

-Protective layer A protective layer protects the whole scintillator layer and has a role which suppresses deterioration of fluorescent substance. The protective layer is made of an organic material, may be any of inorganic materials, may be a combination of both, and may be composed of a laminate of two or more layers. In addition, the moisture-proof protective layer which has a role which suppresses degradation of a scintillator layer is also contained in a protective layer.

  For example, the moisture-resistant protective layer is made of polyparaxylylene, but polymonochloroparaxylylene, polydichloroparaxylylene, polytetrachloroparaxylylene, polyfluoroparaxylylene, polydimethylparaxylylene, polydiethylparaxylylene. It may be made of a xylylene-based material such as len. Further, it may be a protective layer made of polyethylene terephthalate (PET), polymethacrylate, nitrocellulose, cellulose acetate, polypropylene, polyethylene naphthalate, polyurea, polyimide or the like.

The protective layer is made of graphite, iron, copper, aluminum, magnesium, beryllium, titanium, silicon, a composite material of aluminum and carbon, a metal or carbon-based inorganic material such as a composite material of copper and carbon, LiF, MgF ₂ , SiO _2. A protective layer containing a non-metallic inorganic material such as Al ₂ O ₃ , TiO ₂ , MgO, ITO, glass (sodium silicate), or SiN may be used. In the case of a protective layer containing an inorganic material, the protective layer may be composed of an inorganic material alone or a protective layer containing an inorganic material and an organic material. As the protective layer, non-metallic inorganic materials and xylylene polymers such as polyparaxylylene are preferable.

The thickness of the protective layer needs to be thin in order not to diffuse the visible light converted by the scintillator layer, and is preferably 50 μm or less, but is not limited thereto.
The protective layer can be produced by attaching a film containing the above organic material or inorganic material or applying a paint. When a moisture-resistant film such as polyparaxylylene is formed, the support on which the scintillator layer is formed is formed. It is possible to obtain a radiation detector in which the entire surface of the scintillator layer and the support is coated with a polyparaxylylene film by placing it in a vapor deposition chamber of a CVD apparatus and exposing it in vapor sublimated with polyparaxylylene. it can.

Optical coupling layer The optical coupling layer has a function of closely bonding the scintillator layer and the photoelectric conversion element.
The optical coupling layer is transparent so that visible light converted by the scintillator layer by irradiation of radiation reaches the photoelectric conversion element via the optical coupling layer or the outermost layer of the photoelectric conversion element panel, and transmits light. It is preferable that the transmittance is 90% or higher.

  In addition, the thickness of the optical coupling layer needs to be thin so that visible light converted by the scintillator layer is not diffused, and is preferably 50 μm or less, more preferably 30 μm or less.

The component constituting the optical coupling layer is not particularly limited as long as the object of the present invention is not impaired, but a thermosetting resin, a hot melt sheet, and a pressure-sensitive adhesive sheet are preferable.
As a thermosetting resin, resin which has acrylic type, an epoxy type, a silicone type etc. as a main component is mentioned, for example. Of these, resins mainly composed of acrylic and silicon are preferred from the viewpoint of low-temperature thermosetting. Examples of commercially available products include methyl silicone-based JCR6122 manufactured by Toray Dow Corning Co., Ltd.

  The optical coupling layer may be a hot melt sheet. The hot melt sheet in the present invention is a sheet formed of an adhesive resin (hereinafter referred to as hot melt resin) made of a non-volatile thermoplastic material that does not contain water or a solvent and is solid at room temperature. Inserting a hot melt sheet between the adherends, melting the hot melt sheet at a temperature equal to or higher than the melting point, and then solidifying the melt at a temperature equal to or lower than the melting point allows the adherends to be joined together via the hot melt sheet. I can do it. Since hot-melt resin does not contain polar solvent, solvent, and water, it does not deliquesce even when it comes into contact with phosphors having deliquescence (for example, phosphors having a columnar crystal structure made of an alkali halide). Suitable for joining of photoelectric conversion element and scintillator layer. Further, since the hot melt sheet does not contain residual volatiles, shrinkage due to drying is small, and the gap filling property and dimensional stability are also excellent.

  Specific examples of the hot melt sheet include those based on resins such as polyolefin, polyamide, polyester, polyurethane, acrylic, EVA, etc., depending on the main component. Of these, those based on polyolefin, EVA, and acrylic resins are preferred from the viewpoints of light transmittance and adhesiveness.

  The optical coupling layer may be a pressure sensitive adhesive sheet. Specific examples of the pressure-sensitive adhesive sheet include those based on acrylic, urethane, rubber, and silicon. Among these, from the viewpoint of light transmittance and adhesiveness, those mainly composed of acrylic or silicon are preferred.

In the case of a thermosetting resin, the optical coupling layer is applied on the scintillator layer or the photoelectric conversion element by a technique such as spin coating, screen printing, and dispenser.
In the case of a hot melt sheet, the optical coupling layer is formed by inserting the hot melt sheet between the scintillator layer and the photoelectric conversion element and heating under reduced pressure. The pressure-sensitive adhesive sheet is bonded with a lamination device or the like.

It is possible to use an inorganic substance for the optical coupling layer, and as described above, an inorganic substance having transparency such as MgF ₂ , SiO ₂ , Al ₂ O ₃ , glass (sodium silicate) may be used. . Such an optical coupling layer made of an inorganic substance and an optical coupling layer made of an organic substance may be laminated.

Photoelectric conversion element array The photoelectric conversion element array has a role of absorbing emitted light generated in the scintillator layer, converting it into a charge form, converting it into an electric signal, and outputting it to the outside of the radiation image detector. Conventionally known ones can be used.

Here, although the configuration of the photoelectric conversion element array used in the present invention is not particularly limited, it usually has a form in which a substrate, an image signal output layer, and a photoelectric conversion element are stacked in this order.
Among these, the photoelectric conversion element has a function of absorbing light generated in the scintillator layer and converting it into a charge form. Here, the photoelectric conversion element may have any specific structure as long as it has such a function. For example, the photoelectric conversion element used in the present invention can be composed of a transparent electrode, a charge generation layer that is excited by incident light to generate charges, and a counter electrode. Any of these transparent electrodes, charge generation layers, and counter electrodes may be conventionally known ones. The photoelectric conversion element used in the present invention may be composed of an appropriate photosensor. For example, the photoelectric conversion element may be a two-dimensional arrangement of a plurality of photodiodes, or a CCD ( A two-dimensional photosensor such as a charge coupled device (CMOS) or a complementary metal-oxide-semiconductor (CMOS) sensor may be used.

  The image signal output layer has a function of accumulating the charge obtained by the photoelectric conversion element and outputting a signal based on the accumulated charge. Here, the image signal output layer may have any specific structure. For example, the image signal output layer is stored with a capacitor that is a charge storage element that stores the charge generated by the photoelectric conversion element for each pixel. And a transistor that is an image signal output element that outputs the charges as a signal. Here, a TFT (thin film transistor) is given as an example of a preferable transistor.

The substrate functions as a support for the radiation detector and can be the same as the support used in the radiation detector of the present invention described above.
Further, the photoelectric conversion element is a memory unit for storing an image signal based on the intensity information and position information of the X-rays converted into an electric signal, and a power supply unit that supplies electric power necessary for driving the photoelectric conversion element panel Various components that can be included in a photoelectric conversion element panel constituting a known radiation detector, such as a communication output unit for extracting image information to the outside, can be further provided.
The above radiographic image detector can be applied to various types of X-ray imaging systems.

[Example]
EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to this.
[Example 1]
As a support, a polyimide film having a thickness of 125 μm (UPILEX-125S manufactured by Ube Industries, Ltd.) was used.

A reflection layer (0.01 μm) was formed by sputtering aluminum on a 125 μm-thick polyimide film (UPILEX-125S manufactured by Ube Industries) as a support.
A SiO ₂ target was prepared, and a 1 μm thick SiO ₂ thin film was formed on the reflective layer by RF magnetron sputtering. During sputtering, Ar was used as the sputtering gas, the gas pressure was 3 mTorr, and a power of 1 W / cm ² was applied at room temperature to form a subbing layer.

After the undercoat layer was formed, it was introduced into the processing chamber and evacuated to 5 × 10 ⁻² torr or less, then evacuated while introducing oxygen gas, and irradiated with a UV lamp.
Next, as disclosed in Japanese Patent Application Laid-Open No. 2014-167405, the scintillator layer is set by setting the substrate on the substrate holder of the vapor deposition apparatus shown in FIG. A scintillator panel in which was formed.

  As shown in FIG. 2, the vapor deposition apparatus 81 has a box-shaped vacuum vessel 82, and a circle around the center line perpendicular to the vapor deposition substrate 84 is located near the bottom surface inside the vacuum vessel 82. Vapor deposition sources 88a and 88b for vacuum deposition are arranged at positions facing each other. A holder 85 for holding a vapor deposition substrate 84 is disposed above the vapor deposition sources 88a and 88b. The holder 85 is provided with a heater (not shown). The holder 85 is configured to hold the support 84 so that the surface of the vapor deposition substrate 84 on which the scintillator layer is formed faces the bottom surface of the vacuum vessel 82 and is parallel to the bottom surface of the vacuum vessel 82. . The holder 85 is provided with a rotation mechanism 86 that rotates the deposition substrate 84 in the horizontal direction together with the holder 85. The rotation mechanism 86 includes a rotation shaft 87 that supports the holder 85 and rotates the deposition substrate 84 and a motor (not shown) that is disposed outside the vacuum vessel 82 and serves as a drive source for the rotation shaft 87. ing. In addition to the above configuration, the vapor deposition device 81 is provided with a vacuum pump 83 in a vacuum vessel 82. Between the evaporation sources 88a and 88b and the deposition substrate 84, a shutter 89 that blocks a space from the evaporation sources 88a and 88b to the deposition substrate 84 is provided so as to be openable and closable in the horizontal direction. By closing the shutter 89 in the initial stage of vapor deposition, even if substances other than the target substance attached to the surface of the phosphor housed in the evaporation sources 88a and 88b evaporate in the initial stage of vapor deposition, they are used for vapor deposition. Adhesion to the substrate 84 can be prevented.

  First, the phosphor raw material (CsI) was filled in a resistance heating crucible as a vapor deposition material to obtain a vapor deposition source. The reflective layer sample (vapor deposition substrate) was placed on a rotatable holder so that the support surface of the reflective layer sample was in contact with the holder. The distance between the reflective layer sample (deposition substrate) and the evaporation source was adjusted to 400 mm. Next, after evacuating the inside of the vapor deposition apparatus, introducing Ar gas and adjusting the degree of vacuum in the vapor deposition apparatus to 0.5 Pa, while rotating the reflective layer sample (deposition substrate) with the holder at a speed of 10 rpm, The holder was heated to maintain the temperature of the reflective layer sample (deposition substrate) at 200 ° C.

  Next, the resistance heating crucible (deposition source) is heated to deposit the phosphor on the scintillator formation scheduled surface of the reflective layer sample (deposition substrate) to form a scintillator layer. When the scintillator layer has a thickness of 500 μm. Vapor deposition was terminated to obtain a scintillator panel in which a scintillator layer having a predetermined film thickness was formed on the scintillator formation scheduled surface of the reflective layer sample (vapor deposition substrate).

Changes in the surface composition at the scintillator layer interface of the undercoat layer were analyzed by TOF-SIMS. As a result, in the quantitative analysis, (Si strength (appears in the vicinity of Mass = 28) / (O strength (appears in the vicinity of Mass = 18) + Si strength) at the interface of the subbing layer in contact with the scintillator layer) It was confirmed that there was a clear decrease with respect to the site of the layer.
After forming the scintillator layer, the substrate temperature was once cooled to room temperature or lower, and the cross-sectional shape of the scintillator layer was observed with a scanning electron microscope SEM. As a result, no film peeling or cracking was observed.

[Example 2]
Instead of the ultraviolet irradiation treatment for the undercoat layer, dry etching was performed. Etching conditions were a pressure of 50 mTorr, a power of 1200 W, a CHF ₃ flow rate of 70 sccm, and an O ₂ flow rate of 50 sccm. Changes in the surface composition at the scintillator layer interface of the undercoat layer were analyzed by TOF-SIMS. As a result, as in Example 1, (Si strength (appears in the vicinity of Mass = 28) / (O strength (appears in the vicinity of Mass = 18) + Si strength) at the interface in contact with the scintillator layer of the undercoat layer) It was confirmed that there was a clear decrease with respect to the site of the undercoat layer.
After forming the scintillator layer in the same manner as in Example 1, the substrate temperature was once cooled to room temperature or lower, and the cross-sectional shape of the scintillator layer was observed with a scanning electron microscope SEM. As a result, no film peeling or cracking was observed.

[Example 3]
Instead of ultraviolet irradiation treatment for the undercoat layer, argon sputtering treatment was performed. The sputtering conditions were as follows: excitation light: MgKα, power: 400 W, pass energy: 17.90 eV, data point: 0.05 eV / step, capture direction: 40 ° from the sample normal direction.

  Changes in surface composition at the scintillator layer interface of the undercoat layer were analyzed by TOF-SIMS in the same manner as in Example 1. As a result, as in Example 1, (Si strength (appears in the vicinity of Mass = 28) / (O strength (appears in the vicinity of Mass = 18) + Si strength) at the interface in contact with the scintillator layer of the undercoat layer) It was confirmed that there was a clear decrease with respect to the site of the undercoat layer.

  After forming the scintillator layer in the same manner as in Example 1, the substrate temperature was once cooled to room temperature or lower, and the cross-sectional shape of the scintillator layer was observed with a scanning electron microscope SEM. As a result, no film peeling or cracking was observed.

[Comparative Example 1]
A scintillator layer was formed in the same manner as in Example 1 without performing the treatment on the undercoat layer as shown in Examples 1 to 3. Changes in the surface composition at the scintillator layer interface were analyzed by TOF-SIMS in the same manner as in Example 1. As a result, as in Example 1, (Si strength (appears in the vicinity of Mass = 28) / (O strength (appears in the vicinity of Mass = 18) + Si strength) at the interface in contact with the scintillator layer of the undercoat layer) The level of the subbing layer was at the same level as in Example 1. After the scintillator layer was formed in the same manner as in Example 1, the substrate temperature was once cooled to room temperature or lower, and the cross-sectional shape of the scintillator layer was measured with a scanning electron microscope SEM. As a result, film peeling was observed due to thermal contraction.

81: Deposition apparatus 82: Vacuum container 83: Vacuum pump 84: Deposition substrate 85: Holder 86: Rotating mechanism 87: Rotating shaft 88 (88a, 88b): Deposition source 89: Shutter

Claims (8)

at least,
A scintillator layer that converts radiation into visible light;
A reflective layer that reflects visible light converted by the scintillator layer;
An undercoat layer present between the scintillator layer and the reflective layer, at least one of which is in contact with the scintillator layer in the image forming region;
A scintillator panel comprising
The undercoat layer contains a metal compound, the amount of the metal compound is distributed in the undercoat layer, and the atomic percentage of metal elements on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is the undercoat layer. A scintillator panel characterized by being smaller than the atomic percentage of metal elements in other parts of the layer.   The scintillator panel according to claim 1, wherein the metal compound is a metal oxide.   In the scintillator panel, at least one or more atomic% of the substance that becomes a gas at normal temperature and normal pressure on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is 0.1% or more. The scintillator panel according to claim 1 or 2.   The scintillator panel according to any one of claims 1 to 3, wherein the undercoat layer in contact with the scintillator layer in the image forming region is made of only a metal oxide.   5. The scintillator panel according to claim 4, wherein in the scintillator panel, the atomic percentage of carbon on the surface of the undercoat layer in contact with the scintillator layer in the image forming region is 0.1% or less.   The scintillator panel according to any one of claims 1 to 5, wherein the scintillator layer does not include a binder resin.   The scintillator panel according to claim 6, wherein the scintillator layer is made of physical vapor deposition.   8. The scintillator panel according to claim 7, wherein the scintillator layer contains cesium iodide as a main component. 9.

Images