JP2843992B2 - Manufacturing method of radiation image conversion panel - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for manufacturing a radiation image conversion panel having a stimulable phosphor layer, and more specifically, to prevent the intrusion of moisture, guarantee the setting performance, and improve the performance. The present invention relates to a method for manufacturing a radiation image conversion panel having good durability.

[Conventional technology]

Radiation images such as X-ray images are often used for diagnosis of diseases.

In order to obtain this X-ray image, an X-ray image conversion method for directly extracting an image from a phosphor layer instead of a silver halide photosensitive material has been devised.

This method uses radiation transmitted through the subject (generally X-rays)
The phosphor is absorbed by the phosphor, and then the phosphor is excited by, for example, light or heat energy to cause the phosphor to emit radiation energy accumulated by the radiation absorption as fluorescence. It is a method to become.

Specifically, for example, U.S. Pat. No. 3,859,527 and JP-A-55-12144 disclose a radiation image conversion method using a stimulable phosphor and using visible light or infrared light as stimulating excitation light.

This method uses a radiation image conversion panel (hereinafter abbreviated as a conversion panel) having a stimulable phosphor layer (hereinafter abbreviated as a stimulable layer).
The latent image is formed by applying radiation transmitted through the subject to the stimulating layer of the conversion panel, accumulating radiation energy corresponding to the radiation transmittance of each part of the subject, and then forming the stimulating layer. By scanning with stimulating excitation light, the radiation energy stored in each section is emitted and converted into light, and an image is obtained by an optical signal based on the intensity of the light.

This final image may be reproduced as a hard copy or reproduced on a CRT.

The conversion panel used in this radiation image conversion method emits the stored energy by scanning the stimulating excitation light after accumulating the radiation image information, so that the radiation image can be accumulated again after the scanning, and can be used repeatedly. It is possible.

Therefore, it is desirable that the conversion panel has a performance that can withstand long-time use or repeated use many times without deteriorating the image quality of the obtained radiation image. For this purpose, the photostimulable layer of the conversion panel needs to be sufficiently protected from external physical or chemical stimuli.

In the conventional conversion panel, in order to solve the above-mentioned problem, a method of providing a protective layer covering the photostimulated layer surface on the support of the conversion panel, sealing the peripheral edge of the conversion panel, and protecting the photostimulated layer is used. I have been.

This protective layer is formed by directly applying a protective layer coating solution on the photostimulable layer, as described in JP-A-59-42500, for example. It is formed by a method of bonding on the exhausted layer.

Also, for sealing the periphery of the conversion panel, for example, a method of immersing only the periphery of the conversion panel in an organic polymer solution, or applying an organic polymer solution to the periphery to form a polymer film and sealing it. A method of sealing the peripheral portion with a sealant and fixing the sealant from the outside with a fixing member
No. 61-237099), and a method of sealing in a state where the peripheral portion is covered with an extended portion of a protective layer (Japanese Patent Application Laid-Open No. 61-237100).

In order to further improve the moisture resistance, a protective layer having a greater moisture-proof effect than the conventional protective layer is used, and a stimulable layer is surrounded between the support and the protective layer, and the spacer is bonded and sandwiched (Japanese Patent Application (Japanese Patent Application No. 63-141523) has been proposed, and a method of enhancing the moisture-proofing effect by filling the outside of the spacer with a filler also serving as a moisture-proof material has been proposed (Japanese Patent Application No. 63-141523).

[Problem to be solved]

However, such prior art conversion panels,
Although it can prevent intrusion of moisture from the outside when used in a normal atmosphere, it can still be prevented when used under severe temperature and humidity conditions or when a phosphor that is sensitive to moisture is used. Deterioration of the phosphor due to penetration of moisture has been a problem.

In addition, even if a protective layer is provided on the stimulable layer and the periphery of the conversion panel is sealed, the stimulable phosphor absorbs moisture during the process of manufacturing the conversion panel, and the set characteristics of the conversion panel are lost. A drop occurs. Further, since the degree of the moisture absorption largely depends on the atmosphere in the manufacturing process, there is a problem that the characteristics of the conversion panels vary widely and quality reliability is lost. Therefore, when a means of heating and drying is employed, the conversion panel is broken and deformed due to air expansion, so that it is not possible to adopt a sealed form for measuring performance durability.

In view of the above circumstances, an object of the present invention is to provide a radiation image conversion panel that prevents deterioration due to intrusion of moisture into a stimulable phosphor, guarantees setting performance, and has good performance durability.

[Means for solving the problem]

The present invention provides a radiation image conversion apparatus comprising a support, a stimulable phosphor layer, and a protective layer, wherein a spacer surrounding the periphery of the stimulable phosphor layer is provided between the support and the protective layer, and sealed. The panel manufacturing method is characterized in that a notch serving as a ventilation hole is provided in the spacer, the radiation image conversion panel is heated and dried, and then the notch is sealed and hermetically sealed.

In the aspect of the present invention, when sealing the notch and sealing, insert a spacer piece fitted into the notch, sealing,
It is preferable to seal.

The configuration of the conversion panel manufactured according to the present invention includes:
The support and the protective layer are interposed between the photostimulable layer, and a spacer is provided around the periphery of the photostimulable layer. The stimulable layer may be adhered to the support or the protective layer, but it is preferable that the stimulable layer and the protective layer are not in contact with each other, and it is more preferable that a low refractive index layer is present between the stimulable layer and the protective layer.

FIGS. 1 and 2 schematically show an example of a conversion panel manufactured according to the present invention, wherein 1 is a photostimulable layer, 2 is a protective layer, 3 is a support, and 4 is a low refractive index layer. Reference numeral 5 denotes a spacer, and reference numeral 6 denotes a sealing member sealing the notch.

3 and 4 show a form in which a sealing member is further filled outside the spacer.

5 and 6 show a form in which a spacer piece 6 'fitted into the notch is inserted into the notch portion of the spacer, and the space between the spacer and the spacer is sealed with a sealing agent, which contributes to the moisture-proof effect. It is large.

Further, in the present invention, the partition member facing the notch hole inside the notch portion for preventing contamination of the photostimulable layer due to inflow of the sealing member used for sealing the spacer piece is heated. It may be provided in a form that does not hinder drying (degassing).

As the protective layer body used in the present invention, a protective layer body having a good light-transmitting property and capable of being formed into a sheet shape is used. In order to efficiently transmit the photostimulated excitation light and the photostimulated emission, the protective layer preferably has a high light transmittance in a wide wavelength range, and the light transmittance is preferably 80% or more.

Examples of such a material include plate glass such as borosilicate glass and chemically strengthened glass, and organic polymer compounds such as PET, drawn polypropylene, and polyvinyl chloride. Borosilicate glass shows a light transmittance of 80% or more in the wavelength range of 330 nm to 2.6 μm, and quartz glass shows a high light transmittance even at a shorter wavelength.

Further, it is preferable to provide an anti-reflection layer such as MgF _{2 on} the surface of the protective layer body, because it has an effect of efficiently transmitting the stimulating light and the stimulating light and also has the effect of reducing the decrease in sharpness.

The thickness of the protective layer is 50 μm to 5 mm, and preferably 100 μm to 3 mm in order to obtain good moisture proofness.

After forming the photostimulable layer on the support or the protective layer, a spacer is provided between the support and the protective layer so as to surround the photostimulable layer. There is no particular limitation as long as it can be held in a state of being shielded from the atmosphere, and glass, ceramics, metal,
Plastic or the like can be used.

The spacer preferably has a moisture permeability of 30 g / m ² · 24 hr or less. If the moisture permeability is too large, the stimulable phosphor deteriorates due to moisture entering from the outside, which is not preferable.

The thickness of the spacer is preferably equal to or greater than the thickness of the photostimulable layer, and the width of the spacer mainly depends on the moisture-proof property (the moisture permeability) of the contact portion between the spacer, the support and the protective layer. ) And is preferably 1 to 30 mm. If the width of the spacer is too small, it is not preferable from the viewpoints of the stability, strength, and moisture resistance of the spacer. If the size is too large, the size of the conversion panel becomes unnecessarily large, which is not preferable.

In addition, it is preferable that the moisture permeability of the contact portion between the spacer, the support and the protective layer is 30 g / m ² · 24 hr or less.

The spacer is required to be in close contact with the support and the protective layer in order to impart moisture-proof properties to the conversion panel and to keep the thickness of the low refractive index layer constant. Here, for example, an adhesive or the like is used for bringing the spacer into close contact with the support and the protective layer, and the adhesive is preferably one having moisture resistance. Specifically, epoxy resin, phenol resin, cyanoacrylate resin, vinyl acetate resin,
Vinyl chloride resin, urethane resin, acrylic resin,
Organic polymer adhesives such as ethylene vinyl acetate resin, olefin resin, chloroprene rubber, and nitrile rubber, silicone adhesives, and inorganic adhesives containing alumina, silica, and the like as main components, and the like. Among these, epoxy resins and silicone resins used for encapsulating semiconductors and electronic components are preferable because of their excellent moisture resistance,
In particular, epoxy adhesives are suitable because they have low moisture permeability.

For the purpose of improving the adhesion of the spacer support or the contact portion between the spacer and the protective layer body, an undercoat layer may be provided on the contact surface of the spacer, the support and the protective layer body with other layers, Surface treatment can also be performed.

The thus-configured conversion panel is then heated and dried to remove the moisture contained in the photostimulable layer. At this time, it is a feature of the present invention that the spacer has a notch.

The notch of the spacer may be at any part of the spacer or at any number of places, but preferably at one or two places. The width of the notch varies depending on the size of the conversion panel and the number of notches, but is suitably selected from the range of 2 to 40 mm. If the width is too narrow, drying is not performed sufficiently. On the other hand, if the width is too large, it is difficult to seal and seal with an adhesive, or the durability is lowered, which is not preferable.

Heat drying is carried out at 40 to 100 ° C. for 0.1 to 3 hours, and is preferably performed under reduced pressure because the dehumidifying effect is high.

Immediately after the heating and drying, the notch of the spacer is sealed using, for example, the above-mentioned adhesive and sealed. It is more preferable to replace the air inside the conversion panel with a dry gas after drying because the set performance of the conversion panel can be maintained. It is preferable that the notch be sealed and sealed in a dry gas atmosphere because moisture can be prevented from entering through the notch.

The conversion panel manufactured according to the present invention further seals the outside of the spacer and the periphery of the conversion panel with a sealing member.
It is preferable because the moisture-proof effect is enhanced. Sealing is performed by using the above-mentioned adhesive as a sealing member, sealing by glass fusion using sealing glass such as low-melting glass, or sealing with an extension of the protective layer body. Among them, glass fusion is particularly preferred because of its excellent airtightness.

Further, in a mode in which a spacer piece that fits into the notch is inserted, after heating and drying the stimulating layer, the spacer piece may be inserted and sealed with the above-mentioned adhesive.

In this embodiment, the spacer piece is preferably made of the same material as the spacer. The adhesive used preferably has a product of Young's modulus and coefficient of thermal expansion of 0.3 (N / m ² ) ( ⁰ K ⁻¹ ) or less.

In the conversion panel manufactured according to the present invention, it is preferable to have a low refractive index layer between the photostimulable layer and the protective layer, since the sharpness reduction due to the protective layer is suppressed.

The low-refractive-index layer exists in a state where the low-refractive-index layer is shielded from the external atmosphere by the spacer. The provision of the low-refractive-index layer makes it possible to substantially increase the thickness of the protective layer body. In addition, the moisture proof property and durability of the conversion panel can be further improved.

Examples of such a low refractive index layer include a layer made of an inert gas such as air, nitrogen, and argon, and a layer having a refractive index of substantially 1 such as a vacuum layer; ethanol (refractive index: 1.36), methanol (refractive index). 1.33) and diethyl ether (refractive index)
It can also be a layer composed of a liquid such as 1.35). In addition to these, the low refractive index layer may be, for example, CaF ₂ (refractive index 1.23 to 1.
26), Na ₂ AlF ₆ (refractive index 1.35), MgF ₂ (refractive index 1.38), S
It can also be a layer made of a material such as iO ₂ (refractive index 1.46).

The low-refractive-index layer of the conversion panel manufactured by the present invention is preferably a gas layer or a vacuum layer because of its high effect of preventing sharpness from decreasing.

The thickness of the low refractive index layer is practically 0.05 μm to 3 mm.

In order to sufficiently impart the effect of reducing sharpness reduction to the low refractive index layer, the low refractive index layer is preferably in close contact with the photostimulable layer. Therefore, if the low refractive index layer is a liquid layer, a gas layer and a vacuum layer, it may be left as it is, but the low refractive index layer is the above-mentioned CaF ₂ , Na ₃ AlF ₆ , MgF ₂ , SiO _2, etc. When formed on the surface, the stimulable layer and the low-refractive-index layer are brought into close contact with each other by, for example, an adhesive. In this case, the refractive index of the adhesive is preferably close to the refractive index of the photostimulable layer.

The stimulable phosphor used in the present invention, after being exposed to the first light or high-energy radiation,
Stimulation such as thermal, mechanical, chemical or electrical (stimulated excitation)
Is a phosphor that exhibits stimulated emission corresponding to the amount of the first light or high-energy radiation. However, from a practical viewpoint, it is preferably a phosphor that exhibits stimulated emission by excitation light of 500 nm or more. As such a stimulable phosphor,
For example BaSO are described in JP 48-80487 _4: AX,
SrSO are described in JP 48-80489 _4: AX, JP 5
3-39277 Li ₂ B ₄ O ₇ : Cu, Ag, etc.
_{2 O · (B 2 O 2} ) x: Cu and _{Li 2 O · (B 2 O} 2) x: Cu, Ag , etc., in U.S. Pat. No. 3,859,527 SrS: Ce, Sm, SrS : Eu, Sm, La 2 O ₂ S: Eu,
Phosphors represented by Sm and (Zn, Cd) S: Mn.

Further, ZnS: Cu, Pb described in JP-A-55-12142
Phosphor, the general formula BaO · xAl ₂ O _3: barium aluminate phosphor represented by Eu, and the general formula M ^II O · xSiO _2: alkaline earth metal silicate phosphor represented by A are exemplified. Further, an alkaline earth fluoride halide represented by the general formula (Ba ₁ x yMgxCay) FX: eEu ²⁺ described in JP-A-55-12143, described in JP-A-55-12144. and has the general formula LnOX: phosphor represented by xA, the general formulas described in ^{_{JP-a-55-12145 (Ba 1 M II x)}} FX: phosphor represented by yA, JP 55-84389 A phosphor represented by the general formula BaFX: xCe.yA described in JP-A-55-160078; and a rare earth element-activated divalent metal full represented by the general formula M ^II xFX.xA: yLn described in JP-A-55-160078. Orhalide phosphor, general formula ZnS: A, CdS: A, (Zn, Cd) S: A, S: A, ZnS: A,
X and CdS: a phosphor represented by A, X, any one of the following general formulas xM ₃ (PO ₄ ) ₂ .NX ₂ : yAM ₃ (PO ₄ ) ₂ described in JP-A-59-38278. phosphor represented by yA, any one of formulas nReX below that is described in _{JP-a-59-155487 3 · mAX '2: xEu} nReX 3 · mAX' 2: xEu, phosphor represented by ySm the following general are described in JP-a-61-72087 formula ^{M I X · aM II X '} 2 · bM III X "3:. alkali halide phosphor, etc. represented by cA can be mentioned in particular alkali halide phosphor Is preferred since a photostimulable layer can be easily formed by a method such as vapor deposition or sputtering.

In addition, alkaline earth fluorohalide phosphors and alkali halide phosphors are particularly remarkably deteriorated by moisture, and the effect of the present invention is great.

However, the stimulable phosphor used in the present invention is:
The phosphor is not limited to the above-described phosphor, and any phosphor may be used as long as it emits stimulating light when irradiated with stimulating excitation light after irradiation with radiation.

In the method of the present invention, the stimulable phosphor layer comprises:
It is formed on a support or a protective layer by a coating method, a vapor deposition method, or the like.

Such a photostimulable layer may be a photostimulable layer group comprising one or more photostimulable layers containing at least one of the aforementioned photostimulable phosphors. Further, the stimulable phosphor contained in each stimulable layer may be the same or different.

The thickness of the stimulable layer of the conversion panel varies depending on the sensitivity of the intended conversion panel to radiation, the type of stimulable phosphor, etc., but when no binder is contained, a range of 10 μm to 1000 μm, preferably 20 μm to Selected from the range of 800 μm,
When it contains a binder, it is selected from the range of 20 μm to 1000 μm, preferably the range of 50 μm to 500 μm.

Examples of the support used in the present invention include various polymer materials, glass, ceramics, and metals.

Examples of the polymer material include films of cellulose acetate film, polyester film, polyethylene terephthalate, polyamide, polyimide, triacetate, polycarbonate and the like. Examples of the metal include a metal sheet or metal plate of aluminum, iron, copper, chromium, or the like, or a metal sheet or metal plate having a coating layer of the metal oxide. Examples of the glass include chemically strengthened glass and crystallized glass. Examples of the ceramic include a sintered plate of alumina or zirconia.

Further, the layer thickness of these supports varies depending on the material of the support to be used and the like, but is generally 80 μm to 5 mm, and is preferably 200 μm from the viewpoint of easy handling and obtaining good moisture-proof properties. ~ 3mm.

The surface of the support may be a smooth surface or a mat surface for the purpose of improving the adhesion to the stimulable phosphor layer. Also, the surface of the support may be an uneven surface,
A surface structure in which minute tile plates independent of each other are densely arranged may be used.

Further, on these supports, an undercoat layer may be provided on the surface on which the stimulable layer is provided for the purpose of improving the adhesiveness with the stimulable layer, and if necessary, a light reflecting layer and a light absorbing layer may be provided. And so on.

The conversion panel manufactured according to the present invention is used in a radiation image conversion method schematically shown in FIG.

That is, the radiation from the radiation generator 41
The light enters the conversion panel 43 through 42.

This incident radiation is absorbed by the photostimulable layer of panel 43,
The energy is accumulated, and an accumulation image of the radiation transmission image is formed.

Next, the accumulated image is excited by the stimulating light from the stimulating light source 44, and the intensity of the stimulating light is proportional to the amount of accumulated radiation energy. By performing the photoelectric conversion by the conversion device 45, reproducing the image by the image reproduction device 46, and displaying the image by the image display device 47, the radiation transmission image of the subject can be observed.

When the conversion panel is manufactured by the method of the present invention, the stimulable layer from which moisture has been removed by heating and drying can be kept in a dry state, so that the setting performance of the conversion panel can be guaranteed.

〔Example〕

 Next, the present invention will be described with reference to examples.

Example 1 A crystallized glass support (400 mm × 500 mm) having a thickness of 1 mm was set in a vapor deposition apparatus by an electron beam method (EB method). Next, an alkali halide phosphor (RbBr; 0.0006Tl) was placed in a water-cooled crucible and pressed to form a crucible.

Subsequently, the inside of the vapor deposition apparatus was evacuated to a vacuum degree of 5 × 10 ⁻⁶ Torr. Next, while holding the support at 80 to 100 ° C.,
Power was supplied to the B gun to evaporate the stimulable phosphor.

In order to obtain the desired photostimulable layer, the deposition rate was controlled by a film thickness monitor so as to be 10 ⁴ l / min. The electron beam scanned the stimulable phosphor surface of the crucible in a raster shape.

The vapor deposition was terminated when the thickness of the photostimulable layer reached 300 μm.

First, a glass spacer having a thickness of 700 μm and a width of 5 mm is provided on the first layer so that an air layer having a thickness of 400 μm is provided on the photostimulated layer.
They were arranged as shown in the figure, and the spacer was provided with one notch (width 10 mm). The spacer and the support were adhered with an epoxy resin adhesive (AV-138, manufactured by Ciba-Geigy).

Next, a protective layer of glass having a thickness of 1 mm was placed on the spacer, and the portion where the spacer and the protective layer were in contact was adhered with the epoxy resin-based adhesive.

This was dried by heating at 80 ° C. under a reduced pressure of 1 × 10 ⁻² mmHg for 2 hours, and then the notch of the spacer was immediately sealed with the above epoxy resin adhesive and hermetically sealed, as shown in FIG. A conversion panel was manufactured.

Evaluation of the radiation image conversion panel obtained in this way is to leave the conversion panel for 60 days and 120 days under the conditions of 45 ° C and 85% RH for forced deterioration, and to examine the sensitivity reduction rate and fading reduction rate. Performed by

Further, when the stimulable layer on the support is sealed and sealed (sealed) with a protective layer body and a spacer to produce a conversion panel according to the present invention, the rate of decrease in sensitivity and the rate of decrease in fading before and after sealing are determined. Investigation was made to evaluate the performance degradation during the production of the conversion panel. In addition, the performance of the plate before sealing was evaluated in a vacuum and used as a reference in order to remove the influence of moisture. The results are shown in Table 2.

Sensitivity reduction rate: P Irradiate 10mR of X-ray with 80KVp tube voltage, and after t seconds, stimulate excitation by semiconductor laser light (780nm, 20mW), and detect photostimulated emission emitted from photostimulated layer by photodetector The magnitude of the obtained electric signal is converted into the sensitivity S of the conversion panel.
(T sec).

Five seconds after the X-ray irradiation, the sensitivity S ₀ ( ₅ sec) of the conversion panel before sealing, the sensitivity S _st ( ₅ sec) of the conversion panel before the forced degradation test after sealing, and the conversion after the forced degradation test From the sensitivity S ₆₀ ( ₅ sec) of the panel, the sensitivity reduction rate (P) was determined by the following equation.

Fading reduction rate: Q The decay rate of the stored energy between the irradiation of the X-rays and the reading of the signal with the laser beam, that is, the fading: F, can be obtained by the following equation.

However, S ( ₁₂₀ sec) is the sensitivity 120 seconds after X-ray irradiation,
S ( ₅ sec) represents the sensitivity after 5 seconds.

From the fading F ₀ of the conversion panel before sealing, the fading F _st after sealing before the forced deterioration test, and the fading F ₆₀ after the forced deterioration test, the fading reduction rate (Q) was determined by the following equation.

Sharpness Regarding the conversion panel before the forced deterioration test, spatial frequency 1 l
The MTF (modulation transfer function%) at p / mm was determined, and the sharpness of the conversion panel was evaluated.

Examples 2 to 5 A conversion panel was manufactured in the same manner as in Example 1 except that the vacuum drying conditions of the conversion panel, the width of the notch, and the sealing agent used for sealing were as shown in Table 1. did. However, in Example 4, vacuum drying was performed before sealing the protective layer in place of the vacuum drying of Example 1.

The same conversion as in Example 1 was performed on the obtained conversion panel.

Example 6 The thickness of the glass spacer was set to 300 μm, the thickness of the glass protective layer was set to 500 μm, and the bonding surface between the protective layer and the photostimulable layer was bonded with a polyurethane-based adhesive (Cemedine 1300, manufactured by Cemedine). A conversion panel was manufactured in the same manner as in Example 1 except that the conversion panel was performed, and the obtained conversion panel was evaluated.

Example 7 In Example 1, after the notch of the spacer was sealed with an epoxy resin-based adhesive and hermetically sealed, the gap between the support and the protective layer around the spacer was used in Example 1. A conversion panel was manufactured in the same manner as in Example 1 except that the conversion panel was sealed with a system adhesive, and the obtained conversion panel was evaluated.

Example 8 A conversion panel according to the present invention was manufactured in the same manner as in Example 1 except that the stimulable layer was formed by the following method.

The method for forming the photostimulable layer is as follows. First, a coating solution was prepared by dispersing 8 parts by weight of a BaFBr: Eu phosphor having an average particle diameter of 2 μm and 1 part by weight of polyvinyl butyral (binder) using a solvent (cyclohexanone). Next, this coating solution was uniformly applied on the same support as in Example 1 placed horizontally, and left standing all day long to form a photostimulable layer.

The same conversion as in Example 1 was performed on the obtained conversion panel.

Example 9 In Example 1, the notch of the spacer was sealed with an epoxy resin-based adhesive, and then a glass spacer piece having the same width as the notch was further inserted and sealed. A conversion panel was obtained.

Example 10 A conversion panel was obtained in the same manner as in Example 9 except that an acrylic resin was used for the spacer pieces.

The same evaluation as in Example 1 was performed on the conversion panels obtained in Examples 9 and 10.

Comparative Example (1) After forming a photostimulable layer in the same manner as in Example 1, a glass protective layer having a thickness of 1 mm was overlaid on the photostimulable layer, and the peripheral portion of the photostimulable layer was used in Example 1. The panel was sealed with the same epoxy resin-based adhesive as before, and a conversion panel was manufactured. The same conversion as in Example 1 was performed on the obtained conversion panel.

Comparative Example (2) A conversion panel was manufactured in the same manner as in Comparative Example (1) except that a polyethylene terephthalate film having a thickness of 10 μm was used instead of using the glass protective layer. The same conversion as in Example 1 was performed on the obtained conversion panel.

Table 2 also shows the results of evaluation of the conversion panels of Examples 2 to 10 and Comparisons (1) and (2).

[Effects of the Invention] From Table 2, it can be seen that the conversion panels manufactured by the method of the present invention of Examples 1 to 10 can almost completely prevent the invasion of water at the time of manufacturing. The deterioration of the characteristics was remarkably small, and the performance (set performance) at the time of manufacturing the conversion panel was sufficiently maintained. Also, high temperature,
The set performance was maintained for a long period of time even under high humidity, and it had excellent durability. However, in Example 6, since no low refractive index layer was provided between the photostimulable layer and the protective layer, the sharpness of the image was deteriorated.
Further, in Example 7, the deterioration of the performance was extremely small even with the forced deterioration for a longer period. Further, by inserting a notched glass spacer piece as in Example 9, higher durability was exhibited.

[Brief description of the drawings]

1 to 6 are a plan view and a sectional view of an embodiment of a radiation image conversion panel manufactured according to the present invention, FIG. 2 is a sectional view taken along line AA 'of FIG. 1, and FIG. Is B- in FIG.
FIG. 6 is a sectional view taken along the line B ', and FIG. 6 is a sectional view taken along the line CC' of FIG. FIG. 7 is an explanatory diagram of a radiation image conversion method using a radiation image conversion panel. DESCRIPTION OF SYMBOLS 1 ... Photostimulation layer 2 ... Protective layer 3 ... Support 4 ... Low refractive index layer 5 ... Spacer 6 ... Sealing member (notched portion) 6 '... Spacer piece 41 ... Radiation generation Apparatus 42 Subject 43 Radiation image conversion panel 44 Stimulation excitation light source 45 Photoelectric conversion apparatus 46 Radiation image reproducing apparatus 47 Radiation image display apparatus 48 Filter

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-61-237099 (JP, A) JP-A-61-237100 (JP, A) JP-A-63-216000 (JP, A) JP-A-1- 316697 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G21K 4/00

Claims (2)

(57) [Claims] 1. A radiation image comprising a support, a stimulable phosphor layer and a protective layer, wherein a spacer surrounding the periphery of the stimulable phosphor layer is provided between the support and the protective layer to seal the radiation image. In the method for manufacturing a conversion panel, a method for manufacturing a radiation image conversion panel, comprising: providing a notch serving as a ventilation hole in a spacer; heating and drying the radiation image conversion panel; sealing and sealing the notch; . 2. The method of manufacturing a radiation image conversion panel according to claim 1, wherein, when the notch is sealed and sealed, a spacer piece fitted into the notch is inserted, sealed and sealed. Method.