JP2008185567A - Method for manufacturing radiation image conversion panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiation image conversion panel of excellent durability which prevents a substrate from corroding owing to phosphors by using a polyparaxylene film as an isolation film for isolating a phosphor layer from the substrate and keeps the phosphor layer without exfoliation over a long-period because the adhesion between the polyparaxylene film and the phosphor layer is high. <P>SOLUTION: The problem is solved by forming the phosphor layer on the polyparaxylene film through a vapor phase deposition method after forming the polyparaxylene film on the surface of the substrate which has a metal surface and giving plasma treatment to the polyparaxylene film. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a radiation image conversion panel such as a so-called IP (Imaging Plate), and more particularly to a method for manufacturing a radiation image conversion panel that can prevent corrosion of a panel substrate and has excellent durability.

  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 (stimulable (accumulative)) phosphor panel having the photostimulable phosphor layer (stimulable phosphor layer). Radiation image information recording / reproducing system that uses (referred to as “sheet”)) is known, and has been put into practical use, for example, as FCR (Fuji Computed Radiography) manufactured by Fuji Film.
In this system, a radiation image (radiation image) 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 scanned two-dimensionally with excitation light to generate stimulated emission, and this stimulated emission light is photoelectrically read to obtain an image signal, and an image generated based on this image signal is A radiation image of the subject is output to a display device such as a CRT or a recording material such as a photographic photosensitive material.

The conversion panel is usually prepared by dispersing a stimulable phosphor powder in a solvent containing a binder and applying the paint to a glass or resin panel-like support and drying. Created by.
On the other hand, as shown in Patent Document 1, a phosphor panel in which a phosphor layer is formed on a substrate by a vapor deposition method (vacuum film forming method) such as vacuum evaporation or sputtering is also known. Phosphor layers by vapor deposition are formed in a vacuum, so there are few impurities, and since there are almost no components such as binders other than stimulable phosphors, there is little variation in performance and luminous efficiency. Has excellent properties of being very good.

In many cases, the substrate of the conversion panel is also required to act as a reflection layer for the stimulated emission light emitted from the phosphor layer. In addition, due to its light weight, an aluminum plate (aluminum alloy plate) whose surface is polished to a mirror surface is often used as the substrate.
On the other hand, as a stimulable phosphor having good stimulable light emission characteristics, as shown in Patent Document 1, a so-called alkali halide-based compound represented by a general formula, “CsBr: Eu” or “CsCl: Eu” is used. Stimulable phosphors are known.

Here, as is well known, aluminum is subject to significant erosion by halides, particularly moisture-absorbed halides. Therefore, when forming a phosphor layer made of a halide such as an alkali halide using aluminum as a substrate, the substrate is separated from the phosphor layer to prevent corrosion of the substrate by the phosphor. It is necessary to form an isolation layer.
As this isolation layer, Patent Document 1 discloses that a polyparaxylylene film (hereinafter referred to as a parylene film) is used.

  As is well known, a parylene film is a film obtained by polymerizing paraxylylene or a paraxylylene derivative, and is excellent in hydrophobicity, corrosion resistance, heat resistance, and non-gas permeability, and is used as a capacitor derivative film or various protective films. It's being used.

JP 2004-251883 A

  However, although the parylene layer is excellent in the performance of isolating the phosphor layer and the substrate, the adhesion with the phosphor layer decreases with time. For this reason, in a conversion panel in which a phosphor layer (phosphor layer) is formed on a parylene film as disclosed in Patent Document 1, sufficient durability cannot be obtained, and the fluorescent panel is used while being used. The body layer peels off and the conversion panel becomes unusable.

  The object of the present invention is to eliminate the problems based on the above prior art, and in a radiation image conversion panel using a phosphor, by using a polyparaxylylene film as an isolation layer for isolating the phosphor layer and the substrate, To provide a radiation image conversion panel with excellent durability that prevents corrosion of the substrate by the body, has high adhesion between the polyparaxylene film and the phosphor layer, and does not peel off the phosphor layer over a long period of time. It is in.

  To achieve the above object, the present invention forms a polyparaxylylene film on the surface of a substrate having a metal surface, performs plasma treatment on the surface of the polyparaxylylene film, and then performs a vapor deposition method. The present invention provides a method for producing a radiation image conversion panel, wherein a phosphor layer is formed on the polyparaxylylene film.

  In the present invention, it is preferable that an oxide film is formed on the polyparaxylylene film and the phosphor layer is formed on the oxide film.

  In the present invention, the surface of the substrate is preferably an aluminum simple substance or an aluminum alloy.

  According to the present invention having the above-described configuration, when a radiation image conversion panel such as an IP (Imaging Plate) or a flat panel detector is manufactured, a polyparaxylylene film is used as an isolation layer that separates the substrate and the phosphor layer. In addition to preventing corrosion of the substrate due to the phosphor, the polyparaxylylene film and the phosphor layer formed on the polyparaxylylene film by performing plasma treatment on the surface of the polyparaxylylene film It is possible to obtain a radiation image conversion panel excellent in durability, which can obtain a sufficient adhesion force with a film such as the above and can prevent a decrease in the adhesion force and does not peel off the phosphor layer over a long period of time.

  Hereinafter, the manufacturing method of the radiation image conversion panel of this invention is demonstrated in detail with reference to the suitable Example shown by attached drawing.

The conceptual diagram of an example of the radiation image conversion panel produced with the manufacturing method of this invention in FIG. 1 is shown.
The radiation image conversion panel 10 (hereinafter referred to as the conversion panel 10) shown in FIG. 1 basically includes a substrate 12, a polyparaxylylene film 14, and a phosphor layer 18.
The conversion panel 10 has a phosphor layer 18 made of a stimulable phosphor, and captures a radiation image by accumulating (recording) radiation transmitted through the subject, and a radiation image captured by the incidence of excitation light. This is a so-called IP (Imaging Plate) that emits stimulated emission light in response to the above.

  The present invention is not limited to the conversion panel 10 having the phosphor layer 18 made of a stimulable phosphor, and radiation image conversion such as a flat panel detector having a phosphor layer that emits (fluoresces) upon incidence of radiation. A panel (scintillator panel) may be used.

In the present invention, the substrate 12 of the conversion panel 10 is not particularly limited as long as it has a metal surface, and various kinds of materials can be used. In addition, in the conversion panel 10, since the surface of the board | substrate 12 is also calculated | required as an effect | action as a reflective surface of the photostimulated luminescence light which the fluorescent substance layer 18 emitted, it is preferable to have high light reflectivity, such as a mirror surface.
A preferred example of the substrate 12 is a substrate 12 made of aluminum or an aluminum alloy in that it is lightweight and has good light reflectivity, and the effects of the present invention can be suitably expressed. Or the board | substrate 12 formed by forming metal layers, such as an aluminum layer, on the surface of base materials, such as a glass plate, can also be utilized suitably.
In addition, of course, the metal used as the board | substrate 12 and the metal layer formed in the said base material surface may contain trace components, such as magnesium for corrosion prevention.

In the method for manufacturing the conversion panel 10 of the present invention, a polyparaxylylene film 14 (hereinafter referred to as a parylene film 14) is formed on the surface of the substrate 12 as described above.
The parylene film 14 is a film formed by polymerizing paraxylylene or a paraxylylene derivative, and is excellent in corrosion resistance, heat resistance, and non-gas permeability. In the present invention, as described above, the parylene film 14 is provided as an isolation layer (barrier layer) that separates the phosphor layer 18 and the substrate 12 in order to prevent corrosion of the substrate 12 by the phosphor. Thereby, the conversion panel 10 by this invention has implement | achieved the very excellent corrosion resistance of the board | substrate 12. FIG.
Prior to the formation of the parylene film 14, the surface of the substrate 12 is preferably cleaned (preferably, degreased and cleaned) with an alkaline cleaner containing silicate. Furthermore, after washing / drying, it is preferable to perform a primer treatment using a primer for the parylene film 14 such as trimethoxysilylpropyl methacrylate.
Both the cleaning of the substrate 12 and the primer treatment may be performed by a known method using a known cleaning or primer. For example, in the case of a primer treatment using trimethoxysilylpropyl methacrylate, trimethoxysilylpropyl methacrylate is evaporated and the substrate 12 (formation surface of the parylene film 14) is exposed to the vapor.

In the present invention, the parylene film 14 is not particularly limited, and various known parylene films can be used.
In particular,

  Etc.

  Among them, polymonochloroparaxylylene (Parylene C) represented by Chemical Formula 1, polydichloroparaxylylene (Parylene D) represented by Chemical Formula 2, and polytetrafluoroparaxylylene (Parylene HT) represented by Chemical Formula 4 have water permeability. Low and suitable for use. Among them, in particular, polytetrafluoroparaxylylene (Parylene HT) represented by Chemical Formula 4 having high heat resistance is preferably used.

  The method for forming the parylene film 14 is not particularly limited, and may be formed by various known vapor deposition methods such as vacuum deposition, sputtering, CVD (Chemical Vapor Deposition), and plasma polymerization. More precisely, it is formed by a vapor deposition polymerization method.

As an example, using a solid dimer such as diparaxylylene as a raw material, the first step in which vaporization of this diparaxylylene occurs, the second step in which diradical paraxylylene is generated by thermal decomposition of the dimer, and the substrate 12 The adsorption and polymerization of the diradical paraxylylene are performed at the same time to form a high molecular weight polyparaxylylene film, which is a third process.
In this step, the degree of vacuum is generally 0.1 to 100 Pa (10 ^{−3 to 1} Torr), the first step is 100 ° C. to 200 ° C., the second step is 450 ° C. to 750 ° C., the third step. The process is usually performed at room temperature. Moreover, a 3rd process is good also considering the temperature of the board | substrate 12 as the temperature of the range from room temperature to 100 degreeC as needed.

The thickness of the parylene film 14 is not particularly limited, but is preferably 2 μm to 20 μm.
By setting the thickness of the parylene film 14 within the above range, sufficient isolation performance (electrical insulation and moisture isolation) between the phosphor layer 18 and the substrate 12 can be obtained, and peeling can be prevented. To obtain favorable results.
More preferably, the thickness of the parylene film 14 is 5 μm to 15 μm.

  In the method for manufacturing the conversion panel 10 of the present invention, the surface of the parylene film 14 is subjected to plasma treatment, and then the phosphor layer 18 is formed.

Usually, since the parylene film 14 is hydrophobic, even if the phosphor layer 18 is formed on the surface of the hydrophobic parylene film 14, good adhesion is obtained between the parylene film 14 and the phosphor layer 18. I can't.
Therefore, in the manufacturing method of the present invention, after the parylene film 14 is formed, the surface of the parylene film 14 is subjected to plasma treatment. By performing plasma treatment on the surface of the parylene film 14, the surface of the parylene film 14 is modified from hydrophobic to hydrophilic. As a result, sufficient adhesion can be obtained between the parylene film 14 and the phosphor layer 18, and a decrease in adhesion can be prevented, and the phosphor layer 18 does not peel off over a long period of time. Panel 10 can be obtained.

  The plasma processing method is not particularly limited as long as the surface of the parylene film 14 can be irradiated with plasma gas, but a method of radiating plasma to the surface of the parylene film 14 using a plasma gun is exemplified. In addition to this, as the plasma processing method, a known method such as plasma cleaning or PE (plasma etching) used in CVD or the like can be used.

  The gas used for the plasma treatment is not particularly limited as long as it does not react with the surface of the parylene film 14, but a rare gas such as He, Ne, or Ar can be suitably used.

Furthermore, the conditions for the plasma treatment are not particularly limited, and the required durability, that is, the adhesion between the parylene film 14 and the phosphor layer 18, the type of the parylene film 14, the type of the phosphor layer 18, the conversion panel 10 What is necessary is just to determine by layer structure of this, board | substrate size, etc.
According to the study of the present inventor, the plasma processing conditions are that when Ar plasma processing is performed using a plasma gun, the Ar flow rate is 5 sccm to 40 sccm, the plasma discharge voltage is 100 V to 150 V, Preferably, the time is 5 minutes to 120 minutes.

In the method for manufacturing the conversion panel 10 of the present invention, as described above, the phosphor layer 18 is formed on the parylene film 14 after the plasma treatment is performed on the surface of the parylene film 14. As schematically shown in FIG. 1, the phosphor layer 18 formed by vacuum deposition, in particular, the phosphor layer 18 made of an alkali halide phosphor has a columnar crystal structure.
In the method for manufacturing the conversion panel 10 of the present invention, the stimulable phosphor used as the phosphor layer 18 is not particularly limited, and various known phosphors can be used.

In particular, the general formula “M ^I X · aM ^II X” disclosed in Japanese Patent Application Laid-Open No. 61-72087 is disclosed in that the effect of the present invention is easily exhibited and good photostimulated luminescence characteristics are obtained. An alkali halide photostimulable phosphor represented by “ ₂ · bM ^III X” ₃ : cA ”is preferably used.
(In the above formula, M ^I is at least one selected from the group consisting of Li, Na, K, Pb 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, 0 ≦ a <0.5, 0 ≦ b <0.5, and 0 <c ≦ 0.2.)
Among them, have excellent photostimulated luminescence characteristics, and in terms of such the effect of the present invention is obtained particularly well, M ^I contains at least Cs, X contains at least Br, further, A However, 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, 56-116777, 58-69281. 58-206678, 59-38278, 59-75200, and the like, various photostimulable phosphors disclosed in each publication can be suitably used.

The radiation image conversion panel produced in the present invention is not limited to the conversion panel 10 having the phosphor layer 18 made of a stimulable phosphor, and as described above, fluorescence that emits light (fluoresces) upon incidence of radiation. The radiation image conversion panel which has the fluorescent substance layer which consists of a body may be sufficient.
As such phosphors, all known ones can be used. Similarly, the following general formulas are used in that the effects of the present invention are easily manifested and good photostimulated luminescence properties are obtained. :
M ^I X · aM ^II X ′ ₂ · bM ^III X ″ ₃ : zA
An alkali metal halide phosphor represented by the formula is preferably exemplified.
(In the above formula, M ^I represents at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs, and M ^II represents Be, Mg, Ca, Sr, Ba, Ni, Cu, Represents at least one alkaline earth metal or divalent metal selected from the group consisting of Zn and Cd, and M ^III represents Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy , Ho, Er, Tm, Yb, Lu, Al, Ga, and In represent at least one rare earth element or trivalent metal. X, X ′, and X ″ are F, Represents at least one halogen selected from the group consisting of Cl, Br, and I, and A represents Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu , Na, Mg, Cu, A and at least one rare earth element or metal selected from the group consisting of g, Tl, and Bi, and a, b, and z are 0 ≦ a <0.5, 0 ≦ b <0.5, and 0 <, respectively. (Represents a numerical value within the range of z <1.0.)
In particular, it is preferred that Cs is contained as M ^{I in the} general formula, ^I is preferably contained as X, T1 or Na is preferably contained as A, and z is 1 × 10 ^It is preferable that the numerical value is within a range of ⁻⁴ ≦ z ≦ 0.1. Among these, alkali metal halide phosphors represented by the formula “CsI: Tl” are preferably used.

In the manufacturing method of the present invention, the method for forming the phosphor layer 18 is not particularly limited, and various vapor deposition methods such as sputtering and CVD can be used. From the viewpoint of the crystal structure, vacuum deposition is preferably used. In particular, when the phosphor layer 18 made of a stimulable phosphor is formed, the film forming material of the phosphor component and the activator (activator) component is heated with another crucible (evaporation source). Preferably, the phosphor layer is formed by binary vacuum evaporation that evaporates.
There are no particular limitations on the film forming conditions and heating means when performing vacuum vapor deposition, but once the system is evacuated to a high degree of vacuum, argon gas, nitrogen gas, or the like is introduced into the system. It is preferable that the degree of vacuum is about 01 to 3 Pa (hereinafter referred to as medium vacuum for convenience), and vacuum deposition is performed by heating the film forming material by resistance heating or the like under the medium vacuum. The phosphor layer 18 formed by the vapor deposition method is formed of columnar crystals independent of each other. The phosphor layer 14 obtained by forming a film under such a medium vacuum, in particular, an alkali halide such as CsBr: Eu. The phosphor layer 14 of the system has a particularly good columnar crystal structure, and is preferable in terms of photostimulated luminescence characteristics and image sharpness.

  After the phosphor layer is formed in this way, heat treatment (annealing) is performed as necessary, and the phosphor layer 18 is hermetically sealed with a protective film having moisture resistance to produce the conversion panel 10. To do.

  In FIG. 2, an example of the conversion panel by another aspect of the manufacturing method of this invention is shown. In addition, since the conversion panel 20 manufactured by this manufacturing method has the structure similar to the conversion panel 10 shown in FIG. 1 except having the oxide film 22 between the parylene film 14 and the phosphor layer 18, The same members are denoted by the same reference numerals, and the manufacturing method is basically the same, so that different steps will be mainly described.

In the conversion panel 20 shown in FIG. 2, the parylene film 14 is formed in the same manner as the conversion panel 10, and after the plasma treatment is performed on the surface of the parylene film 14, an oxide film is preferably formed on the parylene film 14. 22 is formed.
By having such an oxide film 22, the adhesion between the parylene film 14 and the phosphor layer 18 can be further improved, and the conversion panel 20 having higher durability can be manufactured.

  The oxide film 22 is not particularly limited, and various oxide films can be used. However, silicon oxide is preferable in that an excellent effect of improving the adhesion between the parylene film 14 and the phosphor layer 18 can be obtained. A film, a germanium oxide film, a tin oxide film, a titanium oxide film, a zirconium oxide film, an aluminum oxide film, and the like can be suitably used, and in particular, an effect of improving the adhesion between the parylene film 14 and the phosphor layer 18 is particularly preferable. In this respect, a silicon oxide film can be suitably used.

Although there is no limitation in particular in the film thickness of the oxide film 22, about 0.05 micrometer-3 micrometers are preferable. By setting the thickness of the oxide film 22 within the above range, higher adhesion between the parylene layer 14 and the phosphor layer 18 can be obtained, and the parylene film is completely covered and at the same time, the occurrence of cracks is small. This is preferable.
More preferably, the thickness of the oxide film 22 is 0.1 μm to 2 μm.

The method for forming the oxide film 22 is not particularly limited, and may be formed by a known thin film forming method such as vacuum deposition, sputtering, CVD, or plasma polymerization.
In particular, vacuum deposition is suitable. Note that vacuum deposition may be performed by resistance heating, electron gun heating, or ion beam heating, and a known heating method can be used, and may be appropriately selected depending on the film forming material. . In particular, plasma assisted deposition, in which film formation is performed while irradiating plasma on the substrate being deposited (the surface of the parylene film 14) using a plasma gun or the like, and ion deposition is performed on the substrate being deposited using an ion gun or the like. Ion-assisted vapor deposition in which a film is formed and ion plating in which film formation is performed while ion collision is performed by applying an electric field to a substrate are preferable.
By using plasma assist vapor deposition, ion assist vapor deposition, and ion plating, a dense oxide film 22 having good adhesion can be formed. Among these, plasma-assisted vapor deposition and ion-assisted vapor deposition are particularly preferable because they can form the oxide film 22 with better adhesion.

  As mentioned above, although the manufacturing method of the radiation image conversion panel of this invention was demonstrated in detail, this invention is not limited to the above-mentioned example, In the range which does not deviate from the summary of this invention, various change and improvement are performed. Of course, you may.

  Hereinafter, the present invention will be described in more detail with reference to specific examples of the method for producing a radiation image conversion panel of the present invention.

[Example 1]
As the substrate 12, a plate (thickness 10 mm) made of an aluminum alloy (A5083) having an area of 450 × 450 mm was prepared.
The surface of the substrate 12 (the surface on the side where the phosphor layer 18 is formed) is washed with a cleaning agent, washed with water, dried, and then trimethoxysilyl as a primer by a vacuum apparatus comprising a vapor deposition chamber and a substrate processing chamber. The substrate surface was primed with propyl methacrylate.
Specifically, the substrate 12 was loaded at a predetermined position in the vacuum apparatus substrate processing chamber, and a container containing trimethoxysilylpropyl methacrylate was installed in the evaporation chamber.
After closing the vacuum apparatus, the substrate processing chamber is evacuated until the degree of vacuum in the substrate processing chamber reaches 0.4 Pa, and while continuing the vacuum evacuation, the temperature of the deposition chamber is increased from room temperature to 35 ° C. The degree of vacuum was about 13 Pa, and the surface of the substrate 12 was exposed to trimethoxysilylpropyl methacrylate as a primer to perform a primer treatment.

By using a vapor deposition apparatus for forming a parylene film comprising a raw material evaporation chamber, a thermal decomposition chamber, and a vapor deposition chamber on the surface of the substrate 12 subjected to the primer treatment (the surface of the primer ultrathin film), by chemical vapor deposition. A parylene film 14 having a thickness of 10 μm made of parylene HT was formed.
Specifically, ditetrafluoroparaxylylene was put into a predetermined position of the raw material evaporation chamber of the vapor deposition apparatus, and a container in which the substrate 12 was put in a predetermined position of the vapor deposition chamber was installed.
After closing the vapor deposition apparatus, the inside of the vapor deposition apparatus is evacuated to 0.4 Pa, and the thermal decomposition chamber is heated to keep the temperature at 700 ° C. Then, the temperature of the raw material evaporation chamber is increased from 100 ° C. to 160 ° C. Then, a parylene HT film having a thickness of 10 μm was formed on the surface of the substrate 12 at a speed of about 2 μm / hr.

After the parylene film 14 was formed, the surface of the parylene film 14 was subjected to plasma treatment using a plasma gun.
Specifically, a plasma gun is disposed so that the plasma is directed to the surface of the parylene film 14 formed on the substrate 12, and a voltage of 140 V is applied to the plasma gun while supplying 20 sccm of Ar gas. Plasma was generated, and Ar plasma was irradiated on the surface of the parylene film 14 for 30 minutes to perform plasma treatment of the parylene film 14.

After plasma treatment is performed on the surface of the parylene film 14, europium bromide is used as the activator component material (activator component film forming material), and phosphor component material (phosphor component film forming material). A phosphor layer 18 made of CsBr: Eu (stimulated) was formed on the surface of the substrate by binary vacuum deposition using cesium bromide.
In addition, both film-forming materials were heated with a resistance heating apparatus using a tantalum crucible and a 6 kW DC power source.

The substrate 12 on which the silicon oxide film 16 was formed was set on the substrate holder of the vacuum vapor deposition apparatus, and each film forming material was set at a predetermined position of the vacuum vapor deposition apparatus, and then the vacuum chamber was closed and evacuation was started. For the exhaust, a diffusion pump and a cryocoil were used.
When the degree of vacuum reaches 8 × 10 ⁻⁴ Pa, argon gas is introduced into the vacuum chamber to a degree of vacuum of 0.8 Pa, and then the DC power source is driven to energize the crucible, The formation of the phosphor layer was started. Note that the outputs of the DC power sources of both crucibles were determined according to experiments performed in advance so that the molar concentration ratio of Eu / Cs in the phosphor layer was 0.001: 1 and the film formation rate was 8 μm / min. Adjusted. Further, the substrate was heated by the heating means so that the substrate surface temperature before starting the phosphor layer deposition was 160 ° C.

When the layer thickness of the phosphor layer 18 reached about 700 μm, the DC power supply was stopped, the energization to the crucible and the energization to the heater for heating the substrate were stopped, and the formation of the phosphor layer was completed.
When the temperature of the substrate 12 reached 100 ° C., the substrate (conversion panel 10) was removed from the substrate holder and removed from the vacuum chamber. Thereafter, the substrate 12 was subjected to a heat treatment at a temperature of 200 ° C. for 1 hour under a nitrogen atmosphere, and the conversion panel shown in FIG. 1 was produced.

[Example 2]
A silicon oxide film, which is an oxide film 22 having a thickness of about 0.1 μm, is formed on the surface of the parylene film 14 subjected to the plasma treatment by vacuum deposition using an ion assist method. A conversion panel 20 shown in FIG. 2 was produced in the same manner as in Example 1 except that the phosphor layer 18 was formed on the film.
The film formation conditions of the silicon oxide film as the oxide film 22 are as follows: the temperature in the apparatus is set to 100 ° C., argon gas is introduced into the system, and a 35 A plasma discharge current is supplied. In addition, argon ions were generated, and an EB current of 280 mA was supplied to the electron gun to evaporate SiO ₂ .
The deposition rate was controlled to 8 Å / sec, and a silicon oxide film, which was the oxide film 22, was deposited on the surface of parylene 14.

[Comparative Example 1]
A conversion panel was produced in the same manner as in Example 1 except that the surface of the parylene film 14 was not subjected to plasma treatment.

[Comparative Example 2]
A conversion panel was produced in the same manner as in Example 2 except that the surface of the parylene film 14 was not subjected to plasma treatment.

  The adhesion between the layers of the four types of conversion panels thus prepared was evaluated by the following method.

First, a nail having a surface for nailing (hereinafter simply referred to as a nailing surface) having an area of 20 mm ² is prepared, and the nail surface of the nail is attached to the surface of the phosphor layer of the conversion panel with an adhesive ( Bonding was performed using a product name: Bond Quick 5) manufactured by Konishi. Next, a gauge (manufactured by IMADA, product name: Digital Force Gauge) was fixed to the tip of the nail opposite to the nail driving surface. The gauge was pulled up perpendicularly to the surface of the phosphor layer 14, and the force with which the conversion panel film peeled was measured.
As a result, in the conversion panels of Examples 1 and 2, even when pulled up with a force of 20 kgf, that is, pulled up with a force of 20 kgf / 20 mm ² , film peeling does not occur between any layers as measured by a gauge. It was.
On the other hand, in the conversion panel of Comparative Example 1, film peeling occurred between the parylene film 14 and the phosphor layer 18 when the pulling force was 2 kgf as measured by a gauge. Furthermore, also in the conversion panel of Comparative Example 2, film peeling occurred between the parylene film 14 and the silicon oxide film 16 when the pulling force reached 3 kgf as measured by a gauge.
From the above results, the effects of the present invention are clear.

It is a schematic diagram of an example of the radiation image conversion panel by the manufacturing method of this invention. It is another schematic diagram of the radiation image conversion panel by the manufacturing method of this invention.

Explanation of symbols

10 (Radiation image) conversion panel 12 Substrate 14 Parylene film (polyparaxylylene film)
18 Phosphor layer 22 Oxide film

Claims (3)

  A polyparaxylylene film is formed on the surface of a substrate having a metal surface, a plasma treatment is performed on the surface of the polyparaxylylene film, and then a phosphor layer is formed on the polyparaxylylene film by vapor deposition. Forming a radiation image conversion panel.   The method for manufacturing a radiation image conversion panel according to claim 1, wherein an oxide film is formed on the polyparaxylylene film, and the phosphor layer is formed on the oxide film.   The method for producing a radiation image conversion panel according to claim 1, wherein the surface of the substrate is made of aluminum alone or an aluminum alloy.

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