JP2008014859A - Radiation image conversion panel and method for manufacturing radiation image conversion panel - Google Patents

Abstract

In a radiation image conversion panel, the adhesion strength between a phosphor layer and a protective layer can be improved, and the protective layer is caused by a step between a hillock or a frame fixed on a substrate and the phosphor layer. The radiation that can obtain a high-quality radiation image that minimizes the deterioration of the adhesion strength and the image quality between the protective layer and the phosphor layer due to the floating of the protective layer. An image conversion panel and a method for manufacturing a radiation image conversion panel are provided.
In manufacturing a radiation image conversion panel 10, a panel body 26 having a phosphor layer 14 formed on a substrate 12, a sheet material 30 having a protective layer 36 and a peelable backing film 32 attached thereto, The phosphor layer 14 and the protective layer 36 are laminated so as to face each other, and a first pressure bonding is performed in which the panel body 26 and the sheet material 30 are pressure bonded. Thereafter, the backing film 32 is peeled off from the protective layer 36, and a second pressure bonding is performed in which the protective layer 36 and the panel body 26 are pressure bonded.
[Selection] Figure 1

Description

  The present invention belongs to a technical field of a radiation image conversion panel and a method for manufacturing a radiation image conversion panel, and more specifically, a radiation image conversion panel and a radiation image conversion panel that are pressure-bonded to a protective layer attached to the surface of a phosphor layer. It relates to a manufacturing method.

  When irradiated with radiation (X-rays, α-rays, β-rays, γ-rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated, and then irradiated with excitation light such as visible light, Phosphors that exhibit photostimulated luminescence according to the stored energy are known. This phosphor is called a stimulable phosphor (accumulating phosphor) and is used for various applications such as medical applications.

As an example, a radiation image conversion panel (hereinafter referred to as a conversion panel (also referred to as a radiation image conversion sheet)) having this stimulable phosphor film (stimulable phosphor layer, hereinafter referred to as a phosphor layer). Radiation image information recording / reproducing system using the above) is known, and is put into practical use, for example, as FCR (Fuji Computed Radiography) manufactured by Fuji Photo Film Co., Ltd.
In this system, radiation image information of a subject is recorded on a conversion panel (phosphor layer) by irradiating X-rays or the like through a subject such as a human body. After recording, the conversion panel is two-dimensionally scanned with excitation light such as laser light to generate stimulated emission, and this stimulated emission is read photoelectrically to obtain an image signal, which is reproduced based on this image signal. The obtained image is output as a radiation image of the subject to a display device such as a CRT or a recording material such as a photographic photosensitive material.

A conversion panel is usually prepared by preparing a paint in which a stimulable phosphor powder is dispersed in a solvent containing a binder, and applying the paint to a glass or resin panel-like substrate, followed by drying. Created.
On the other hand, a conversion panel in which a phosphor layer is formed on a substrate by a vacuum film formation method (vapor phase film formation method) such as vacuum deposition or sputtering is also known. The phosphor layer formed by the vacuum film formation method is formed in a vacuum, so there are few impurities, and since there are almost no components such as binders other than the stimulable phosphor, there is little variation in performance, and the luminous efficiency Has excellent properties of being very good.

One factor that deteriorates the characteristics of the conversion panel in which the phosphor layer is formed by the vacuum film formation method is a minute unevenness (small protrusion, hereinafter referred to as hillock) generated on the surface of the phosphor layer.
The phosphor layer, in particular, an alkali halide phosphor layer having good characteristics, has a columnar crystal structure. During the growth of this columnar crystal, the columnar crystal locally grows abnormally or adjacent columnar crystals. As shown in FIG. 4A, hillocks 150 are generated on the surface of the phosphor layer 114.
FIG. 4A is a diagram schematically showing a part of the conversion panel when hillocks 150 are generated on the surface of the phosphor layer 114.

Another factor that deteriorates the characteristics of the conversion panel is moisture absorption of the phosphor layer 114.
The phosphor layer 114, particularly an alkali halide stimulable phosphor layer having good characteristics, has high hygroscopicity and easily absorbs moisture even in a normal (normal temperature / normal humidity) environment. As a result, the photostimulable light emission characteristics, that is, the sensitivity, and the crystallinity of the photostimulable phosphor are degraded (for example, if the alkali halide photostimulable phosphor having a columnar structure is collapsed) As a result, the sharpness of the reproduced image is reduced.
In order to eliminate such inconvenience, a conversion panel is known in which a moisture-proof transparent sheet is used as the protective layer 136 and the phosphor layer 114 is covered with the protective layer 136 and sealed.

  For example, in Patent Document 1, as one method for forming the protective layer 136 on the surface of the phosphor layer 114, a protective layer 136 (humidity resistant film) and a support for the protective layer 136 are provided to prevent handling and wrinkles. Using a sheet material (laminated film) obtained by laminating a backing film (removable film), the protective layer 136 of the sheet material and the phosphor layer 114 face each other and are laminated / press-bonded, and then the protective layer 136 A radiation image conversion panel obtained by peeling off a backing film from a resin is disclosed.

  Here, when the surface of the phosphor layer 114 having the hillock 150 described above is covered with a coating such as the protective layer 136, the protective layer 136 does not follow the hillock 150 as shown in FIG. It floats from the phosphor layer 114 as if a tent was attached to the center. When the image on the conversion panel is reproduced in this state, not only the image defect caused by the hillock 150 itself but also all the portions where the protective layer 136 is lifted from the phosphor layer 114 by the hillock 150, that is, the tent centering on the hillock 150. The entire region becomes an image defect. As a result, the image defect caused by the hillock 150 can be visually recognized as a point defect on the radiographic image, and as a result, various diagnoses and examinations are hindered.

  As shown in the schematic diagram of FIG. 4B, a conversion panel in which a frame 120 is fixed to a substrate 112 and a phosphor layer 114 is formed in the frame 120 is also known. In order to seal the phosphor layer 114 of such a conversion panel, a coating such as a protective layer 136 is attached to the surface of the phosphor layer 114 and the upper surface of the frame 120. At this time, as shown in FIG. 4B, the protective layer 136 does not follow the step between the surface of the phosphor layer 114 and the upper surface of the frame 120, and the end portion of the protective layer 136 floats from the phosphor layer 114. Such a float causes not only point defects and unevenness but also a problem that the strength of the protective layer 136 is weaker than that of the surroundings, and also causes a decrease in the adhesion strength between the protective layer 136 and the phosphor layer 114. . When the image on the conversion panel is reproduced in this state, unevenness occurs in the region where the protective layer 136 at the image edge of the conversion panel is lifted from the phosphor layer 114. As a result, it becomes difficult to accurately diagnose the result of the image edge, which hinders various diagnoses and examinations.

JP-A-2005-172800

  An object of the present invention is to solve the problems of the prior art, and in a radiation image conversion panel in which a phosphor layer is covered with a protective layer by a vapor deposition method, the adhesion strength between the phosphor layer and the protective layer. In addition, this protective layer can minimize the floating of the protective layer due to the step between the frame fixed on the substrate of the hillock or the radiation image conversion panel and the phosphor layer. A radiation image conversion panel capable of obtaining a high-quality radiation image with minimal deterioration in adhesion strength and image quality deterioration between the protective layer and the phosphor layer caused by floating, and a method for manufacturing the radiation image conversion panel It is to provide.

  In order to achieve the above object, the present invention has a phosphor layer formed by a vapor deposition method, and in manufacturing a radiation image conversion panel in which the phosphor layer is covered with a protective layer, A panel body formed by forming a phosphor layer and a sheet material formed by adhering the protective layer and a peelable backing film, the surface of the protective layer without the backing film or the surface of the phosphor layer or After applying the adhesive on both sides, the phosphor layer and the protective layer are laminated so as to face each other, and a first pressure bonding is performed to pressure-bond the panel body and the sheet material. The present invention provides a method for producing a radiation image conversion panel, wherein a backing film is peeled off and second pressure bonding is performed to pressure-bond the protective layer and the panel body.

  In this invention, it is preferable that the adhesive agent which adhere | attaches the said fluorescent substance layer and the said protective layer is a thermoplastic resin, and the said 1st crimping | compression-bonding and 2nd crimping | compression-bonding are thermocompression bonding.

  In the present invention, the protective layer preferably has a thermal conductivity of 0.01 W / m · K to 10.0 W / m · K.

  In the present invention, the Young's modulus of the protective layer is preferably 0.01 GPa to 100 GPa.

  Moreover, in this invention, it is preferable that the thickness of the said protective layer is 1 micrometer-20 micrometers.

  In the present invention, the protective layer has a thermal conductivity of 0.1 W / m · K to 0.3 W / m · K, a Young's modulus of 1 GPa to 10 GPa, and a thickness of 1 μm to 10 μm. Is preferred.

  In order to achieve the above object, the present invention provides a radiation image conversion panel manufactured by any one of the above-described methods for manufacturing a radiation image conversion panel.

The present invention uses a sheet material in which a backing film and a protective layer are attached for the purpose of handling and wrinkle prevention in a radiation image conversion panel in which a phosphor layer by a vapor deposition method is covered with a protective layer or the like. First, pressure bonding is performed to press the sheet material and the phosphor layer, and after the backing film is peeled off from the protective layer (sheet material), the second pressure bonding is performed to press the protective layer and the phosphor layer.
Therefore, the present invention uses a sheet material with a backing film and a protective layer adhered to improve handling properties and prevent the protective layer from wrinkling, and the first pressure bonding sufficiently provides the workability of peeling the backing film. In addition to securing the protective layer, it is possible to follow the step between the surface of the hillock or the phosphor layer and the upper surface of the frame by performing the second pressure bonding, and the floating of the protective layer due to these can be minimized. As a result, it is possible to obtain a high-quality radiographic image by minimizing the image quality degradation of the radiographic image due to the floating, and to improve the yield of the radiation image conversion panel, and to protect due to the floating. It is also possible to prevent a decrease in adhesion strength between the layer and the phosphor layer.

  Hereinafter, the radiation image conversion panel and the method for manufacturing the radiation image conversion panel of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic production process diagram showing one embodiment of a method for producing a radiation image conversion panel of the present invention.

  In the present embodiment, a radiation image conversion panel (hereinafter simply referred to as a conversion panel) 10 of the present invention has a phosphor layer 14 formed by a vapor deposition method, and this fluorescence is transmitted through an adhesive layer 38. When manufacturing the conversion panel 10 (see FIG. 1D) in which the body layer 14 is covered with the protective layer 36, as shown in FIG. 1A, the phosphor layer 14 is attached to the substrate 12 to which the frame 20 is fixed. A radiation image conversion panel main body (hereinafter simply referred to as a conversion panel main body) formed by forming a protective layer 36 and a peelable backing film 32 are attached, and the backing film 32 is not attached. As shown in FIG. 1B, the sheet material 30 having the adhesive layer 38 formed on the surface of the protective layer 36 is laminated with the phosphor layer 14 and the protective layer 36 (adhesive layer 38) facing each other. The sheet material 30 and the conversion panel body 26 are pressure-bonded. That first performs compression, then peeled off the backing film 32 from the protective layer 36 are those formed by performing a second crimp crimping the protective layer 36 and the conversion panel body 26.

  As shown to Fig.1 (a), the sheet | seat material 30 is comprised by the backing film 32, the protective layer 36, and the contact bonding layer 38 in this embodiment.

  In the present invention, the backing film 32 serves as a support for the protective layer 36 to be bonded to the phosphor layer 14, and can be peeled off from the protective layer 36, such as a seal with a general-purpose backing sheet. .

  In the present invention, as described above, the backing film 32 is peeled off before obtaining the conversion panel 10 of the present invention, which is the final application, and therefore does not need to be transparent, and the forming material is not particularly limited. Contains olefin plastics such as polyethylene and polypropylene, vinyl plastics such as polyvinyl chloride and polyacrylonitrile, polyester plastics such as polyethylene terephthalate and polybutylene terephthalate, polyurethane plastics, acrylic plastics, and bisphenol A as the bisphenol component Plastics such as polycarbonate can be preferably used.

  Further, the backing film 32 is a plastic such as polyarylate, polycarbonate, polyester carbonate containing a bisphenol component having a substituted or unsubstituted cycloalkylidene group, an alkylidene group having 5 or more carbon atoms or an aralkylene group as a part of the bisphenol component. Is preferred. Specifically, 1,1-bis (4-hydroxyphenyl) -cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 3,3-bis ( Plastics such as polycarbonate, polyarylate and polyester carbonate having 4-hydroxyphenyl) -pentane, 4,4-bis (4-hydroxyphenyl) -heptane, and bis (4-hydroxyphenyl) -phenylmethane as the bisphenol component are also used. be able to.

  Furthermore, as the backing film 32, plastics such as polyethersulfone, polysulfone, polyamide, and cellulose triacetate can be suitably used. In addition, a cyclic olefin-based or norbornene-based plastic or an amorphous polyester-based plastic having a fluorene skeleton can also be suitably used.

  In particular, the backing film 32 is preferably a film made of a polyolefin plastic such as polyethylene or polypropylene, or a polyester plastic such as polyethylene terephthalate or polybutylene terephthalate.

  In the present invention, the thickness of the backing film 32 is not particularly limited, but is preferably 10 μm to 500 μm, and more preferably 20 μm to 150 μm. By setting the thickness of the backing film 32 to 10 μm or more, it becomes possible to support the protective layer 36 and facilitate handling when the protective layer 36 is laminated on the surface of the phosphor layer 14 and the upper surface of the frame 20. In addition, by setting the thickness of the backing film 32 to 500 μm or less, the sheet material 30 and the conversion panel 26 are sufficiently crimped in winding or first crimping after the protective layer 36 is adhered to the backing film 32. be able to.

  In the present invention, the peeling force of the backing film is preferably small, but if it is too small, problems such as foaming tend to occur during the processing of the laminated film. On the other hand, if it is too large, problems such as deformation of the film during re-peeling occur. Accordingly, the peel strength is preferably in the range of 10 g / 25 mm to 70 g / 25 mm, and more preferably in the range of 15 g / 25 mm to 50 g / 25 mm.

  In the present invention, the protective layer 36 covers the highly hygroscopic phosphor layer 14 to prevent the phosphor layer 14 from absorbing moisture, is excellent in moisture proofness, and has a high incidence of radiation and phosphor. There is no particular limitation as long as it has optical characteristics that do not hinder emission of emitted light from the layer 14.

In the present invention, the thermal conductivity of the protective layer 36 is not particularly limited, but is preferably 0.01 W / m · K to 10.0 W / m · K, and more preferably 0.1 W / m · K. More preferably, it is K to 0.3 W / m · K.
When the thermal conductivity of the protective layer 36 is 0.01 W / m · K or more, heat can be effectively conducted to the adhesive layer 38 when thermocompression bonding (thermal lamination) is performed as the first pressure bonding. In particular, when the sheet material 30 and the surface of the phosphor layer 14 and the upper surface of the frame (conversion panel body 26) are bonded via the adhesive layer 38 formed of a thermoplastic resin, the sheet material 30 Sufficient adhesion strength between the surface of the phosphor layer 14 and the upper surface of the frame can be ensured. Further, when the thermal conductivity of the protective layer 36 is 0.01 W / m · K or more, heat can be effectively conducted to the adhesive layer 38 even when thermal lamination is performed as the second pressure bonding. In particular, when the adhesive layer 38 is formed of a thermoplastic resin, the adhesive layer 38 can be softened and the tackiness can be increased. As a result, the protective layer 36 adheres to the surface of the phosphor layer 14 and the surface of the phosphor layer 14 and the upper surface of the frame 20 with the hillock on the surface of the phosphor layer 14 and the step difference between the surface of the phosphor layer 14 and the upper surface of the frame 20 being adhered. It becomes possible to do. Further, since the thermal conductivity of the protective layer 36 is 10.0 W / m · K or less, the heat is applied to the protective layer 36 and the phosphor layer 14 when the thermal lamination is performed as the first and second pressure bonding. Therefore, it is possible to prevent the protective layer 36 and the phosphor layer 14 from being damaged excessively.

In the present invention, the Young's modulus of the protective layer 36 is not particularly limited, but is preferably 0.01 GPa to 100 GPa, and more preferably 1 GPa to 10 GPa.
When the Young's modulus of the protective layer 36 is 0.01 GPa or more, it is possible to prevent the protective layer 36 from being damaged by the first and second pressure bonding. Further, since the Young's modulus of the protective layer 36 is 10 GPa or less, the protective layer 36 has a step between the hillock 50 on the surface of the phosphor layer 14 and the surface of the phosphor layer 14 and the upper surface of the frame 20 during the second pressure bonding. It becomes possible to follow.

In the present invention, the thickness of the protective layer 36 is not particularly limited, but is preferably 1 μm to 20 μm, and more preferably 1 μm to 10 μm.
When the thickness of the protective layer 36 is 1 μm or more, handling when the protective layer 36 is stuck to the backing film 32 can be easily performed. Further, since the thickness of the protective layer 36 is 20 μm or less, the sheet material 30 and the conversion panel main body 26 can be sufficiently attached during the first pressure bonding, and the second pressure bonding is performed. In this case, the protective layer 36 can follow the hillock 50 on the surface of the phosphor layer 14 and the step between the surface of the phosphor layer 14 and the upper surface of the frame 20.

  In the present invention, the protective layer 36 is not particularly limited, and a known film (sheet) can be used as long as it has sufficient moisture resistance, strength, transparency, and chemical stability. Can be arbitrarily selected from known materials such as polyethylene terephthalate, polyethylene naphthalate, polyamide, polyimide, aramid resin, polycarbonate, polyethylene, polyurethane, polypropylene, and polyvinylidene chloride.

In the present invention, the protective layer 36 is not a single layer structure as shown in FIG. 1, but an inorganic layer such as a metal oxide, a metal nitride, or a metal oxynitride is laminated on the above-described film. It may be a thing. As an example, the film laminated on the film is preferably a transparent deposited layer in which an inorganic substance having a light barrier property and a gas barrier property is deposited at a wavelength of 300 nm to 1000 nm. Preferred examples of the inorganic substance having a light absorption at a wavelength of 300 to 1000 nm include silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, zirconium oxide, tin oxide, silicon oxynitride, and aluminum oxynitride. Among these, aluminum oxide, silicon oxide, and silicon oxynitride are particularly preferable because they have high light transmittance and high gas barrier properties, that is, a dense film with few cracks and micropores can be formed.
Further, the film laminated on the above-described film is not limited to a single layer structure, and may be a two-layer structure of inorganic layers. Each inorganic layer may be made of the same material even if it is made of different materials. There may be.

  Furthermore, the film laminated on the above-described film may have a three-layer structure in which an organic-inorganic composite compound layer is provided between the inorganic layer and the inorganic layer. The organic-inorganic composite compound layer is a layer made of a composite material of various inorganic materials and various organic materials. By having such a composite layer, it is possible to fill in the defects of the inorganic layer, it is possible to maximize the moisture-proof performance of the inorganic layer disposed on both sides, the functional film of the three-layer structure, A high-quality conversion panel 10 that can prevent deterioration of the phosphor layer 14 due to moisture absorption over a long period of time can be realized.

  As the organic-inorganic composite compound layer, a layer made of a composite material of various inorganic materials and organic materials can be used as long as it can transmit radiation and stimulated emission light. As an inorganic material, for example, (a) a substance that forms the above moisture-proof layer, such as silicon oxide, in powder form, (b) one or more metal alkoxides and hydrolysates thereof, and ( c) At least one kind of tin chloride is used. On the other hand, as the organic material, a water-soluble polymer substance such as polyvinyl alcohol (PVA) or methyl cellulose is used.

  The organic-inorganic composite compound layer is formed by applying a coating agent containing the inorganic material and the organic material as an aqueous solution or a water / alcohol mixed solution and using the mixture as a main component. The specific forming method is not particularly limited, and various coating methods such as sol-gel method, gravure coating, roll coating, doctor blade coating, dip coating, slide coating and extrusion coating, screen printing method, spraying method, etc. Various film forming means can be used. The thickness of the organic-inorganic composite compound layer is not particularly limited, but is a thickness that can provide good moisture-proof performance, and can prevent the total thickness of the protective layer 14 from being increased. It is preferable that it is 0.3 micrometer-1 micrometer. Further, the ratio of the inorganic material to the organic material in the organic-inorganic composite compound layer is such that the defect filling effect of the functional film 38 can be suitably obtained, that is, the organic-inorganic composite compound layer itself exhibits moisture resistance and the protective layer 36 as a whole. From the standpoint that the organic-inorganic composite compound layer can exhibit a barricade effect, the amount of the organic material is preferably 10 wt% to 50 wt%, particularly preferably 20 wt% to 40 wt%.

In the present invention, the adhesive layer 38 is used for sealing and adhering the phosphor layer 14 with the protective layer 36 (sheet material 30). The adhesive layer 38 is adapted to receive radiation and emit emitted light from the phosphor layer 14. There is no particular limitation as long as it has optical characteristics that do not hinder, but thermoplastic resins such as polyester, polyamide, polyimide, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal, methyl polymetalate, polycarbonate, and polyurethane are preferable. .
Advantages of using the thermoplastic resin will be described in detail later in the method for manufacturing a conversion panel.

  On the other hand, as shown in FIG. 1A, in this embodiment, the conversion panel body 26 includes a substrate 12, a frame 20 fixed on the substrate 12, and a phosphor layer 14 formed inside the frame 20. It is comprised by.

In the present invention, the substrate 12 is not particularly limited, and various substrates used in ordinary phosphor panels can be used according to heat resistance against subsequent vapor deposition and heat treatment.
Examples include plastic films such as cellulose acetate film, polyester film, polyethylene terephthalate film, polyamide film, polyimide film, triacetate film and polycarbonate film; formed from quartz glass, alkali-free glass, soda glass, heat-resistant glass (Pyrex ^TM, etc.), etc. Examples of such a glass plate include: a metal sheet such as an aluminum sheet, an iron sheet, a copper sheet, and a chromium sheet; or a metal sheet having a metal oxide coating layer;
In the present invention, the substrate 12 may be the film or the sheet itself, or a reflective film for reflecting the photostimulated luminescent light on the surface of the base material, or further reflected on the reflective film. You may have a barrier film for protecting a film | membrane, the protective film of a base material, etc.

In the present embodiment, a frame 20 having a predetermined thickness, outer shape, and width is provided on the surface of the substrate 12 in accordance with the formation region of the phosphor layer 14 on the substrate 12 (that is, the imaging region of the phosphor panel).
The shape of the frame 20 is not particularly limited, and may be appropriately limited according to the imaging region of the conversion panel 10. However, in the illustrated example, the shape is a quadrangular prism with open upper and lower surfaces.
Further, the material for forming the frame 20 is not particularly limited, but for example, the same material as that of the substrate 12 is preferable in order to reduce deformation due to a difference in coefficient of thermal expansion when the temperature of the conversion panel 10 changes.

  In the present embodiment, as described above, the frame 20 is provided on the substrate 12, and the protective layer 36 for sealing the phosphor layer 14 is adhered to the frame 20. When sealing 14, the surface of the phosphor layer 14 and the protective layer 36 can be bonded on substantially the same plane, so that the phosphor layer 14 can be easily sealed and sealed. The phosphor layer 14 can be protected at times.

The phosphor forming the phosphor layer 14 is not particularly limited, and various types can be used. Preferably, a photostimulable phosphor that exhibits stimulated emission in a wavelength range of 300 nm to 500 nm by excitation light having a wavelength of 400 nm to 900 nm is used.
As a preferred example, an alkali halide photostimulable phosphor represented by a general formula “M ^I X · aM ^II X ′ ₂ · bM ^III X ₃ ″: cA” disclosed in JP-A-61-72087. Is exemplified.
(In the above formula, M ^I is at least one selected from the group consisting of Li, Na, K, Rb and Cs, and M ^II is Be, Mg, Ca, Sr, Ba, Zn, Cd, Cu and at least one trivalent metal selected from the group consisting of Ni, M ^III is, Sc, Y, La, Ce , Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, At least one trivalent metal selected from the group consisting of Tm, Yb, Lu, Al, Ga and In, and X, X ′ and X ″ are selected from the group consisting of F, Cl, Br and I A is from Eu, Tb, Ce, Tm, Dy, Pr, Ho, Nd, Yb, Er, Gd, Lu, Sm, Y, Tl, Na, Ag, Cu, Bi, and Mg. At least one selected from the group consisting of . Also, a 0 ≦ a <0.5, a 0 ≦ b <0.5, it is 0 <c ≦ 0.2.)

In particular, M ^I includes at least Cs, X includes at least Br, and has A in that it has excellent stimulated light emission characteristics and the effects of the present invention can be satisfactorily obtained. An alkali halide photostimulable phosphor that is Eu or Bi is preferred, and among these, photostimulable phosphors represented by the general formula “CsBr: Eu” are particularly preferred.

  In addition, U.S. Pat. No. 3,859,527, JP-A-55-12142, 55-12144, 55-12145, 57-148285, and 56-116777. Stimulable phosphors disclosed in publications such as 58-69281, 59-75200, and 59-38278 are also preferred.

In the present invention, the phosphor layer 14 is preferably made of such a stimulable phosphor, and is obtained by various vapor deposition methods such as vacuum deposition, sputtering, and CVD (Chemical Vapor Deposition).
Among them, the phosphor layer 14 formed by vacuum deposition is preferable in terms of productivity and the like, and in particular, the material of the phosphor component and the material of the activator (activator) component are separately heated and evaporated. The phosphor layer 14 formed by multi-source vacuum deposition is preferable.

The phosphor layer 14 is not limited to any particular film formation conditions. The phosphor layer is obtained by appropriately forming film conditions determined according to the film formation method, the composition of the phosphor layer 14 to be formed, and the like. 14 may be sufficient. As an example, in the case of vacuum deposition, a phosphor layer obtained by forming a film at a film formation rate of 0.05 μm / min to 300 μm / min at a vacuum degree of 1 × 10 ⁻⁵ Pa to 1 × 10 ⁻² Pa. 14 is preferred. In addition, when formed by multi-source vacuum evaporation, the evaporation rate of both materials is controlled so that the amount ratio of the base component and the activator component falls within the target range.
Further, according to the examination by the applicant of the present application, when the above-mentioned various photostimulable phosphors, particularly alkali halide photostimulable phosphors, especially CsBr: Eu, are formed by vacuum deposition, the system is once used. After evacuating the interior to a high degree of vacuum, argon gas, nitrogen gas or the like is introduced into the system to obtain a medium vacuum degree of about 0.01 Pa to 3 Pa, particularly about 0.5 Pa to 1.5 Pa. It is preferable to form the phosphor layer 14 by performing vacuum deposition by resistance heating or the like. Although the alkali halide phosphor layer 14 such as CsBr: Eu has a columnar crystal structure, the phosphor layer 14 obtained by forming a film under such a vacuum has a particularly good columnar crystal structure. It is preferable in terms of the sharpness of the photostimulated luminescence characteristic image.
Further, the phosphor layer 14 formed may be heated at 300 ° C. or lower, preferably 200 ° C. or lower during film formation by heating the substrate 12 or the like.
Furthermore, although there is no limitation also in thickness, the fluorescent substance layer 14 of 50 micrometers or more, especially 200 micrometers or more is preferable.

  In the present embodiment, the adhesive layer 38 is formed on the surface of the protective layer 36 of the sheet material 30. However, the present invention is not limited to this, and the surface of the phosphor layer 14 of the conversion panel body 26 is not limited thereto. It may be provided.

  Hereinafter, the manufacturing method of the conversion panel 10 of this invention is demonstrated.

In the present embodiment, as a preferred example, a thermoplastic resin is used for the adhesive layer 38 that bonds the protective layer 36, the surface of the phosphor layer 14 and the upper surface of the frame 20, and the first pressure bonding and the heat bonding (thermocompression bonding) are performed by thermal lamination (thermocompression bonding). The second pressure bonding is performed.
In the method for manufacturing the conversion panel 10 of the present invention, first, as shown in FIGS. 1A to 1B, the phosphor layer 14 of the conversion panel 26 was formed with a thermoplastic resin on the surface of the sheet material 30. The adhesive layer 38 is laminated so as to face each other. Next, the substrate 12 is heated so that the temperature of the substrate 12 becomes 100 ° C. to 130 ° C. Note that the heating temperature of the substrate 12 at this time may be appropriately determined according to the adhesive layer 38. Moreover, although the heating of the board | substrate 12 here makes it possible to implement a thermal lamination more effectively as 1st crimping | compression-bonding mentioned later, it is not necessarily required.
After the heating of the substrate 12, as shown in FIG. 1 (b), in this embodiment, the surface of the sheet material 30 is moved while being pressed by the roller 60, and thermal lamination is performed as the first pressure bonding. Then, the sheet material 30 and the surface of the phosphor layer 14 and the upper surface of the frame 20 are pressure-bonded via the adhesive layer 38. Preferably, thermal lamination is performed while the roller 60 is heated and / or the substrate 12 is heated and pressed. Note that the heating temperature of the roller 60 and / or the substrate 12 at this time may be appropriately determined according to the adhesive layer 38.

Next, as shown in FIG. 1C, the backing film 32 is peeled from the protective layer 36.
Thereafter, as shown in FIG. 1 (d), the surface of the protective layer 36 is moved while being pressed by the same roller 60 as described above, and thermal lamination is performed as a second pressure bonding, whereby the protective layer 36 and the phosphor The surface of the layer 14 and the upper surface of the frame 20 are pressure bonded. In this case as well, it is preferable to perform thermal lamination in which the roller 60 is heated and / or the substrate 12 is heated and pressure-bonded.
It should be noted that the heating temperature of the roller 60 and / or the substrate 12 at this time may be appropriately determined according to the adhesive layer 38.

  As described above, the method for manufacturing the conversion panel 10 of the present invention uses the sheet material 30 to which the backing film 32 and the protective layer 36 are adhered, thereby improving handling properties and preventing the protective layer 36 from wrinkling. The first pressure bonding can sufficiently secure the peeling workability of the backing film 32. Moreover, the manufacturing method of the conversion panel 10 of this invention can strengthen the adhesive force of the protective layer 36 and the fluorescent substance layer 14 by performing 2nd crimping | compression-bonding. Further, by performing the second pressure bonding, in the conventional report such as Patent Document 1 described above, as shown in FIG. 4A, a step between the surface of the hillock 150 or the phosphor layer 114 and the upper surface of the frame 120 is obtained. The protective layer 36 floats due to the above, but the protective layer 36 can be made to follow the hillock 50 as shown in FIG. 2A, and further, as shown in FIG. 36 can follow the level difference between the surface of the phosphor layer 14 and the upper surface of the frame 20, and the floating of the protective layer 36 due to these can be minimized. As a result, it is possible to minimize the degradation of the image quality of the radiation image due to the float and to prevent the decrease in the adhesion strength between the protective layer 36 and the phosphor layer 14 due to the float. Can be obtained. Furthermore, the yield of the radiation image conversion panel can be improved.

In particular, in the present embodiment, when the adhesive layer 38 is formed of a thermoplastic resin, the adhesive layer 38 is softened and the tackiness is increased by performing thermal lamination as the first pressure bonding. The adhesion strength between the material 30 (protective layer 36) and the surface of the phosphor layer 14 and the upper surface of the frame 12 is improved, and the sheet material 30 and the surface of the phosphor layer 14 and the upper surface of the frame 12 can be adhered with sufficient adhesion. it can.
In particular, in this embodiment, when the adhesive layer 38 is formed of a thermoplastic resin, the adhesive layer 38 is softened and the tackiness is increased by performing thermal lamination as the second pressure bonding. In a state where the layer 36 follows the hillock 50 as shown in FIG. 2 (a), or the protective layer 36 follows the step between the surface of the phosphor layer 14 and the upper surface of the frame 16 as shown in FIG. 2 (b). In this state, it is adhered to the surface of the phosphor layer 14 and the upper surface of the frame 20.

  In the present embodiment, the adhesive layer 38 is formed of a thermoplastic resin, but the present invention is not limited to this. For example, a UV curable adhesive may be used. In this case, after manufacturing the conversion panel 10, the adhesive is applied to the protective layer 36 of the sheet material 30, and the adhesive application surface of the sheet material 30 is opposed to the phosphor layer 14 of the conversion panel 26 and laminated. The first pressure bonding is performed, and then the backing film 32 of the sheet material 30 is peeled off, and then the second pressure bonding is performed. After the second pressure bonding, the adhesive is cured by UV irradiation. Even in this case, by using the sheet material 30 on which the backing film 32 and the protective layer 36 are adhered, the handling property is improved and the protective layer 36 is prevented from being wrinkled. Can be secured sufficiently. In addition, by performing the second pressure bonding, the adhesion between the protective layer 36 and the phosphor layer 14 can be further increased. Further, the protective layer 36 can be made to follow the hillock 50, and the surface of the phosphor layer 14 and It is possible to follow a step with the upper surface of the frame 20.

Further, in the present embodiment, the first pressure bonding is thermal lamination (thermocompression bonding). However, in the manufacturing method of the conversion panel 10 of the present invention, the present invention is not limited to this, and when the backing film 32 is peeled, Pressure bonding that can sufficiently bond the surface of the protective layer 36 of the sheet material 30 to the surface of the phosphor layer 14 and the upper surface of the frame 20 so that the protective layer 36 is not peeled off from the surface of the phosphor layer 14 together with the backing film 32. Any crimping method may be used.
Similarly, in the present embodiment, the second pressure bonding is thermal lamination (thermocompression bonding). However, in the present invention, the present invention is not limited to this, and the hillock 50 or fluorescent light having the protective layer 36 on the surface of the phosphor layer 14 is not limited thereto. Any crimping method may be used as long as the crimping method can follow the step between the surface of the body layer 14 and the upper surface of the frame 20.

  In the present embodiment, both the first pressure bonding and the second pressure bonding are performed from the front side of the phosphor panel 10, but the manufacturing method of the conversion panel 10 of the present invention is not limited to this. The at least one pressure bonding may be a pressure from the back surface of the substrate 12.

  In the present embodiment, the conversion panel 10 manufactured by the manufacturing method of the present invention is configured to have the frame 20, but the present invention is not limited to this, and as shown in FIG. Without providing the frame 20 on 12, the phosphor layer 14 is formed on the substrate 12 according to the imaging region of the conversion panel 10, the protective layer 36 is adhered to the phosphor layer 14 and the surface of the substrate 12, and fluorescence The body layer 14 may be sealed.

  As mentioned above, although the radiographic image conversion panel of the present invention manufactured by the manufacturing method of the radiographic image conversion panel of the present invention and the manufacturing method of the present invention has been described in detail, the present invention is not limited to the above-described embodiment. It goes without saying that various improvements and changes may be made without departing from the spirit of the invention.

It is a schematic manufacturing-process figure which shows one Embodiment of the manufacturing method of the radiation image conversion panel of this invention. (A) It is the figure which represented typically a part of radiation image conversion panel of this invention in which the protective layer follows the hillock in the fluorescent substance layer surface. (B) It is the figure which represented typically a part of radiation image conversion panel of this invention in which the protective layer follows the level | step difference of the fluorescent substance layer surface and a frame upper surface. It is a schematic block diagram which shows another embodiment of the radiation image conversion panel of this invention manufactured with the manufacturing method of this invention. (A) It is the figure which represented typically a part of conventional radiation image conversion panel at the time of hillock producing on the fluorescent substance layer surface. (B) It is the figure which represented typically a part of conventional radiation image conversion panel in case a protective layer does not follow a fluorescent substance layer surface and a frame upper surface.

Explanation of symbols

10 Radiation image conversion panel 12, 112 Substrate 14, 114 Stimulable phosphor layer 20, 120 Frame 22 Groove 26 Radiation image conversion panel body 30 Sheet material 32 Backing film 36, 136 Protective layer 38 Adhesive layer 50, 150 Hillock

Claims (7)

When manufacturing a radiation image conversion panel having a phosphor layer formed by a vapor deposition method and covering the phosphor layer with a protective layer,
A panel body formed by forming the phosphor layer on a substrate, and a sheet material formed by adhering the protective layer and a peelable backing film, the surface of the protective layer without the backing film or the surface of the phosphor layer After applying an adhesive to one or both of the above, the phosphor layer and the protective layer are laminated so as to face each other, and a first pressure bonding is performed to pressure-bond the panel body and the sheet material,
Then, the said backing film is peeled from the said protective layer, The 2nd crimping | compression-bonding which crimps | bonds the said protective layer and the said panel main body is performed, The manufacturing method of the radiation image conversion panel characterized by the above-mentioned.   2. The radiation image conversion panel according to claim 1, wherein an adhesive that bonds the phosphor layer and the protective layer is a thermoplastic resin, and the first pressure bonding and the second pressure bonding are thermocompression bonding. Method.   The method for manufacturing a radiation image conversion panel according to claim 1, wherein the protective layer has a thermal conductivity of 0.01 W / m · K to 10.0 W / m · K.   The method for producing a radiation image conversion panel according to claim 1, wherein the protective layer has a Young's modulus of 0.01 GPa to 100 GPa.   The method for producing a radiation image conversion panel according to claim 1, wherein the protective layer has a thickness of 1 μm to 20 μm.   The protective layer has a thermal conductivity of 0.1 W / m · K to 0.3 W / m · K, a Young's modulus of 1 GPa to 10 GPa, and a thickness of 1 μm to 10 μm. A method for producing the radiation image conversion panel according to claim 1.   The radiation image conversion panel manufactured by the manufacturing method of the radiation image conversion panel in any one of Claims 1-6.

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