JP2003167099A - Method of manufacturing radiological image converting panel long body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of stably manufacturing a long body of a radiological image converting panel capable of providing a radiological image of high quality. <P>SOLUTION: In this method of continuously manufacturing a radiological image converting panel having a base and a phosphor layer, the long base is sent out while applying the tensile force thereto by a feed roller of which the moment of inertia is controlled within a range of 0.5-20kg.m<SP>2</SP>, further a long phosphor sheet composed of a phosphor and a binder is sent out by another feed roller while applying the tensile force thereto, the base and the phosphor sheet are overlapped to each other, and then heated and pressed by a calender roller to adhere the phosphor sheet onto the base to form the phosphor layer, simultaneously the phosphor layer is compressed, and then the base with the phosphor layer is taken up by a take-up roller while applying the tensile force thereto. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a radiation image conversion panel used in a radiation image information recording / reproducing method utilizing a stimulable phosphor.

[0002]

2. Description of the Related Art When radiation such as X-rays is irradiated, a part of the radiation energy is absorbed and accumulated, and then, when irradiated with electromagnetic waves (excitation light) such as visible light and infrared rays, the accumulated radiation energy is changed. A stimulable phosphor having a property of emitting light (such as a stimulable phosphor exhibiting stimulated luminescence) is used to apply a test object to a sheet-shaped radiation image conversion panel containing the stimulable phosphor. After the radiation image information of the subject is once stored and recorded by irradiating the transmitted or emitted radiation from the subject, the panel is scanned with excitation light such as laser light and sequentially emitted as emitted light, and the emitted light is emitted. A radiation image information recording / reproducing method, which consists of photoelectrically reading an image signal to obtain an image signal, is widely used in practice. The panel that has finished reading is erased of the remaining radiation energy, and then prepared and used repeatedly for the next imaging.

A radiation image conversion panel (also called a stimulable phosphor sheet) used in a radiation image information recording / reproducing method.
Is composed of a support and a stimulable phosphor layer provided thereon as a basic structure. However, when the stimulable phosphor layer is self-supporting, a support is not always necessary.
A protective layer is usually provided on the upper surface of the stimulable phosphor layer (the surface not facing the support) to protect the phosphor layer from chemical alteration or physical impact. There is.

The phosphor layer usually comprises stimulable phosphor particles and a binder containing and supporting the phosphor particles in a dispersed state. However,
The phosphor layer is formed only by an aggregate of stimulable phosphors without a binder formed by a vapor deposition method or a sintering method, or a polymer substance is provided in a gap between the aggregates of stimulable phosphors. Those impregnated with are also known.

Further, as another method of the above-mentioned method of recording / reproducing radiation image information, Japanese Patent Application No. 2000-400426 filed by the present applicant.
In the specification, a radiation image conversion panel containing at least a stimulable phosphor (phosphor for energy storage) and a radiation image conversion panel which separates a radiation absorption function and an energy storage function in a conventional stimulable phosphor. Then, a radiation image forming method has been proposed which uses a combination with a phosphor screen containing a phosphor that emits light in the ultraviolet to visible region (phosphor for absorbing radiation). In this method, radiation that has passed through a subject is first converted into light in the ultraviolet or visible region by the radiation-absorbing phosphor of the screen or panel, and the light is then converted into a radiation image by the energy-storing phosphor of the panel. Store and record as information. Next, the panel is scanned with excitation light to emit emitted light, and the emitted light is photoelectrically read to obtain an image signal. Such a radiation image conversion panel and a fluorescent screen are also included in the present invention.

The radiation image information recording / reproducing method (and the radiation image forming method) has a number of excellent advantages as described above, and even the radiation image conversion panel used in this method is as high as possible. It is desired to provide an image having high sensitivity and good image quality (sharpness, graininess, etc.).

As a method for continuously producing a long body of the above-mentioned radiation image conversion panel, as described in Japanese Patent No. 2597516, a long phosphor sheet composed of a phosphor and a binder is used. It is sent out from a roll while applying tension, the phosphor sheet and a long-sized support sent out from another roll are superposed, and the phosphor is continuously heated and pressed using a calendar roll to obtain a phosphor. A method is known in which the sheet is joined to a support and the phosphor sheet that becomes the phosphor layer is compressed.
By compressing and attaching the phosphor layer on the support, the packing density of the phosphor in the phosphor layer is increased, so that the image quality of the radiation image formed using the obtained radiation image conversion panel can be improved. it can.

When carrying out such a continuous process, it is desirable to elongate the elongated body in order to improve the productivity. However, if the length of the elongated body is increased, vibration due to expansion and contraction of the support caused by a difference in tension between the support delivery roll and the take-up roll of the support (laminate) provided with the phosphor layer, Vibration due to slippage on the calendar roll increases. Then, these vibrations cause unevenness in the rotation speed of the calendar roll, and further cause uneven compression of the phosphor layer, which causes unevenness in the packing density of the phosphor, and thus manufactured. Artifacts (image defects) may be generated on a radiation image formed by using the radiation image conversion panel.

[0009]

DISCLOSURE OF THE INVENTION As a result of studying the above-mentioned problems in the continuous calendering process, the present inventor has found that the inertia moment applied to the roll becomes small especially in the latter half of the stage where the support is fed from the feed roll. It was found that the vibration amplitude increases due to the expansion and contraction of the support. Therefore, by attaching a flywheel to the feed roll of the support and controlling the moment of inertia of the roll within a certain range, the vibration of the support is effectively suppressed,
It has been found that the calendar process can be carried out stably.

Therefore, the present invention is to provide a method for stably producing a long body of a radiation image conversion panel which gives a high quality radiation image.

[0011]

The present invention is a method for producing a long body of a radiation image storage panel having a phosphor layer on a support, wherein the moment of inertia is 0.5 to 20 kg.m.
^From the delivery roll controlled within the range of ² , the long support is delivered under the application of tension, while the other delivery roll is made up of the long phosphor consisting of the phosphor and the binder. The sheet is sent out under tension, the support and the phosphor sheet are superposed, and pressed under heating with a calendar roll to bond the phosphor sheet to the support to form a phosphor layer. At the same time, the phosphor layer is compressed, and then the support provided with the phosphor layer is wound with a winding roll under tension.

In the present invention, the long support also includes a support provided with an auxiliary layer such as an undercoat layer on one or both sides thereof.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the manufacturing method of the present invention, the moment of inertia of the support feeding roll is 0.5 to 10 k.
It is preferable to control within the range of g · m ² . It is preferable to control the moment of inertia of the delivery roll by mounting a flywheel on the fixed shaft of the support delivery roll.

The difference between the tension when the support is fed and the tension when the support is wound is preferably in the range of 0 to 1000 g / cm. The diameter of the support delivery roll is preferably in the range of 100 to 2000 mm, and the diameter of the support take-up roll is preferably in the range of 100 to 2000 mm.

The elastic modulus of the long support is 1000 to 1
It is preferably in the range of 0000 MPa, and the elastic modulus of the elongated phosphor sheet is preferably in the range of 50 to 500 MPa.

The method for manufacturing the radiation image storage panel of the present invention will be described in detail below, taking the case where the phosphor is a stimulable phosphor as an example.

The elongated support is generally a sheet or film made of a flexible resin material, metal, ceramic or the like and having a thickness of 50 μm to 1 mm. A resin material is preferable. The support may be transparent, or the support may contain a light-reflecting substance for reflecting excitation light or emitted light (eg, alumina particles, titanium dioxide particles, barium sulfate particles), Alternatively, voids may be provided. Alternatively, the support may contain a light absorbing substance (eg, carbon black) for absorbing excitation light or emitted light. Examples of the resin material that can be used for forming the support include polyethylene terephthalate,
Various resin materials such as polyethylene naphthalate, aramid resin, and polyimide resin can be mentioned.

In a known radiation image conversion panel, it is known to provide an undercoat layer to enhance the adhesiveness between the support and the phosphor layer. In addition, in order to improve the sensitivity or image quality (sharpness, graininess) of the panel, a light reflecting layer made of a light reflecting substance such as titanium dioxide, or a light absorbing layer made of a light absorbing substance such as carbon black, etc. It is known to provide. Also for the support used in the present invention, it is possible to provide these various layers, their configuration is the purpose of the desired radiation image conversion panel,
It can be arbitrarily selected according to the application. Further, for the purpose of improving the sharpness of the image, the surface of the support on the side of the phosphor layer (the undercoat layer (adhesion-imparting layer) on the surface of the support on the side of the phosphor layer, a light reflection layer or a light absorption layer, etc.) When the auxiliary layers are provided, they may be the surfaces of these auxiliary layers), and fine irregularities may be formed.

The elastic modulus of the thus obtained long-sized support (including the auxiliary layer when the support is provided with the auxiliary layer) is determined by the vibration of the support in the calendar treatment step described later. In order to suppress
It is preferably in the range of 0 MPa.

Separately, a long phosphor sheet is prepared.
The stimulable phosphor is preferably a stimulable phosphor that emits stimulated emission in the wavelength range of 300 to 500 nm when irradiated with excitation light in the wavelength range of 400 to 900 nm. Examples of such stimulable phosphors are described in detail in JP-B-7-84588, JP-A-2-193100 and JP-A-4-310900. As a preferred stimulable phosphor, an alkaline earth metal halide phosphor activated with europium or cerium (eg, BaFBr:
Examples thereof include Eu, BaF (Br, I): Eu), and cerium-activated rare earth oxyhalide-based phosphors.

Of these, the rare earth activated alkaline earth metal fluoride halide stimulable phosphor represented by the basic composition formula (I): M ^II FX: zLn ... (I) is particularly preferable. However, M ^II is B
represents at least one alkaline earth metal selected from the group consisting of a, Sr and Ca, and Ln represents Ce, Pr, S
m, Eu, Tb, Dy, Ho, Nd, Er, Tm and Y
Represents at least one rare earth element selected from the group consisting of b. X represents at least one halogen selected from the group consisting of Cl, Br and I. z is 0 <z ≦
It represents a numerical value within the range of 0.2.

As M ^II in the above basic composition formula (I),
It is preferable that Ba accounts for more than half. Ln is preferably Eu or Ce. Further, in the basic composition formula (I), it appears as F: X = 1: 1 in the notation, but this shows that it has a BaFX type crystal structure, and the stoichiometric composition of the final composition is shown. It does not indicate the composition. In general, a state in which a large number of F ⁺ (X ⁻ ) centers, which are vacancy points of X ⁻ ions, are generated in the BaFX crystal is preferable in order to enhance the photostimulation efficiency for light of 600 to 700 nm. At this time, F is often slightly over X.

Although omitted in the basic composition formula (I), the following additives may be added to the basic composition formula (I), if necessary. bA, wN ^I , xN ^II , yN ^III where A represents a metal oxide such as Al ₂ O ₃ , SiO ₂ and ZrO ₂ . In preventing sintering between M ^II FX particles, it is preferable to use an average particle size of the primary particles has low reactivity with M ^II FX in the following ultrafine particles 0.1 [mu] m. N ^I represents a compound of at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs, N ^II represents a compound of an alkaline earth metal consisting of Mg and / or Be, and N ^III is Al, Ga, In,
It represents a compound of at least one trivalent metal selected from the group consisting of Tl, Sc, Y, La, Gd and Lu. As these metal compounds, it is preferable to use halides as described in JP-A-59-75200, but it is not limited thereto.

Further, b, w, x and y are respectively M ^II
It is the amount of addition when the number of moles of FX is 1, and is 0.
≦ b ≦ 0.5, 0 ≦ w ≦ 2, 0 ≦ x ≦ 0.3, 0 ≦ y ≦
It represents a numerical value within each range of 0.3. These figures do not represent the elemental ratios contained in the final composition with respect to additives that are reduced by firing and subsequent cleaning treatments. In addition, some of the above compounds may remain as the compounds just added in the final composition,
^Some react with or are incorporated into ^II FX.

In addition to the above basic composition formula (I), if necessary, Z described in JP-A-55-12145 can be used.
n and Cd compounds; TiO ₂ , BeO, MgO, C which are metal oxides described in JP-A-55-160078.
aO, SrO, BaO, ZnO, Y ₂ O ₃ , La ₂ O ₃ , I
n ₂ O ₃ , GeO ₂ , SnO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , Th
O ₂ ; Zr and Sc compounds described in JP-A-56-116777; B compound described in JP-A-57-23673; As described in JP-A-57-23675.
And Si compounds; tetrafluoroboric acid compounds described in JP-A-59-27980; JP-A-59-4728.
Hexafluorosilicic acid, hexafluorotitanic acid, and hexafluorozirconic acid monovalent or divalent salts described in JP-A No. 9-58; V, Cr described in JP-A-59-56480; Mn, F
Compounds of transition metals such as e, Co and Ni may be added. Further, in the present invention, not only the phosphor containing the above-mentioned additive, but any substance having a composition which is basically regarded as a rare earth activated alkaline earth metal fluorohalide stimulable phosphor. May be

The rare earth activated alkaline earth metal fluorohalide stimulable phosphor represented by the above basic composition formula (I) usually has an aspect ratio of 1.0 to 5.0. . The stimulable phosphor particles used in the radiation image storage panel according to the present invention generally have an aspect ratio of 1.0 to 2.
0 (preferably 1.0 to 1.5), and the median diameter (Dm) of particle size is 1 μm to 10 μm.
(Preferably 2 μm to 7 μm), and σ / Dm where σ is the standard deviation of the particle size distribution
Is 50% or less (preferably 40% or less). Further, the shape of the particles includes a rectangular parallelepiped type, a regular hexahedron type, a regular octahedron type, a 14-sided type, an intermediate polyhedron type and an irregular type crushed particle.
A tetrahedral type is preferable.

However, in the present invention, the phosphor is not limited to the stimulable phosphor, and may be a phosphor that absorbs radiation such as X-rays and emits light (instantaneously) in the ultraviolet or visible region. . An example of such a phosphor is LnT.
aO ₄ : (Nb, Gd) system, Ln ₂ SiO ₅ : Ce system, L
nOX: Tm system (Ln is a rare earth element), CsX system (X is a halogen), Gd ₂ O ₂ S: Tb, Gd ₂ O ₂
S: Pr, Ce, ZnWO ₄ , LuAlO ₃ : Ce, Gd
_{3 Ga 5 O 12: Cr,} Ce, it may be mentioned such as HfO _2.

The particulate stimulable phosphor is dispersed and dissolved in a suitable organic solvent together with a binder to form a coating solution. The ratio of binder to phosphor in the coating solution is usually 1: 1 to 1: 1.
The value should be in the range of 00 (weight ratio). This ratio is particularly preferably in the range of 1: 8 to 1:40 (weight ratio). Various types of resin materials are known for the binder that dispersively supports the stimulable phosphor particles, and in the formation of the phosphor layer according to the present invention, any known binder resin is mainly used. It can be appropriately selected and used from resin materials. The coating solution further contains a dispersant for improving the dispersibility of the phosphor in the coating solution,
A plasticizer for improving the binding force between the binder and the phosphor in the phosphor layer after formation, an anti-yellowing agent for preventing discoloration of the phosphor layer, a curing agent, a cross-linking agent, etc. Additives may be mixed.

The coating solution thus prepared is uniformly applied to the surface of the peelable temporary support by an appropriate application means to form a coating film. The temporary support can be arbitrarily selected from the above supports and can be peeled off by adding a release agent or the like thereto. Further, as a coating means, a doctor blade, a roll coater, a knife coater, or the like can be used. Then, the coating film is dried to complete the production of the phosphor sheet.
The thickness of the phosphor sheet varies depending on the characteristics of the intended radiation image conversion panel, the type of phosphor, the mixing ratio of the binder and the phosphor, etc., but is usually in the range of 20 μm to 1 mm, and preferably It is in the range of 50 to 500 μm.

The elastic modulus of the phosphor layer of the obtained long phosphor sheet is 50 to 500 M in order to suppress the vibration of the support and the laminate in the following calendar treatment step.
It is preferably in the range of Pa.

The above long support and phosphor sheet are heated and pressed by a calendering apparatus as shown in FIGS. 1 and 2 to form a phosphor layer on the support.

FIG. 1 is a schematic sectional view of a calendering apparatus used in the method of the present invention, and FIG. 2 is a schematic side view of a support delivery roll provided in the calendering apparatus. Figure 1
In the calendar processing device, the support delivery roll 11, the support tension pickup rolls 12a, 12
b, phosphor sheet delivery roll 13, intermediate roll 14
a, 14b, temporary support take-up roll 15, phosphor sheet tension pickup rolls 16a, 16b, 1
6c, primary calendar roll 17, secondary calendar roll 1
8, tension pickup rolls 19a for laminated body, 1
9b, and a laminate winding roll 20.

In the present invention, the support delivery roll 11
As shown in FIG. 2, a flywheel (flywheel) 33 is attached to the shaft center (fixed shaft) 32 of the roll body 31. The moment of inertia of the roll body 31 varies depending on the material and thickness of the support, the length of one roll, etc.
With the installation of this flywheel 33, generally 0.5
It is controlled within the range of 20 to 20 kg · m ² . Preferably, the moment of inertia is controlled within the range of 0.5 to 10 kg · m ² .

By controlling the moment of inertia of the support delivery roll 11 within the above range, it is possible to effectively suppress the expansion and contraction of the support and the vibration due to the slip on the calendar roll. In particular, even in the latter half of feeding the support in which the winding diameter of the roll is small, the inertia moment is maintained above a certain level, so that the amplitude of vibration can be prevented from increasing.

The calendar roll is composed of a primary roll 17 and a secondary roll 18, and is composed of a pair of upper and lower rolls 17a and 17b and 18a and 18b, respectively. Each of the pair of rolls is a metal roll and / or a rubber roll. The primary roll 17 is a driven roll, and the lower secondary roll 18b is a drive roll.

The elongated support 21 wound around the support delivery roll 11 is delivered from the roll 11,
Tension pickup rolls 12a, 12b for support
Through to the primary roll 17. At this time, tension is applied to the support 21. This tension is added to the support 21 by suitably changing the rotation speed and the rotation timing between the delivery roll 11 and the secondary roll 18. Tension pickup rolls 12a, 1
Reference numeral 2b is a load (tension) detecting means, and the rotation condition of the delivery roll 11 or the secondary roll 18 is adjusted as necessary based on the detected tension.

On the other hand, the long phosphor sheet 22 wound around the phosphor sheet feeding roll 13 is the roll 1
After being sent out from No. 3 and passing through the intermediate rolls 14a and 14b, only the peelable temporary support 23 of the phosphor sheet 22 is taken up by the temporary support take-up roll 15. The phosphor sheet 22 ′ (consisting only of the phosphor layer) from which the temporary support has been peeled off passes through the tension pickup rolls 16 a, 16 b, 16 c for the phosphor sheet, and then the primary roll 1
Head to 7. At this time, the phosphor sheet 22 (and 2
2 ') is under tension. This tension is added to the phosphor sheet 22 by suitably changing the rotation speed and the rotation timing between the delivery roll 13 and the secondary roll 18. In addition, the rotation condition of the delivery roll 13 or the secondary roll 18 is adjusted as necessary based on the tension detected by the tension pickup rolls 16a to 16c.

The support 21 and the phosphor sheet 22 'are superposed on each other immediately before the primary roll 17, and then the primary roll 1 is formed.
7. Then, it is heated and pressurized while passing through the secondary roll 18. Generally, the heat treatment is performed in the temperature range of 30 ° C. to 200 ° C., and the pressure treatment is performed in the pressure range of 5 to 100 MPa. By this heat and pressure treatment, the support 21
A phosphor sheet (that is, a phosphor layer) 22 'is adhered and integrated on the top. At the same time, the phosphor layer is compressed, the voids in the phosphor layer are reduced, and the packing density of the phosphor is increased.

Support (laminate) 2 provided with a phosphor layer
3 is a tension pickup roll 19a for laminated body,
After passing through 19b, it is wound by the laminate winding roll 20. At this time, the laminate 23 is under tension. This tension is applied to the secondary roll 18 and the take-up roll 2.
It is added to the laminated body 23 by suitably changing the rotation speed and the rotation timing with respect to zero. In addition, the rotation condition of the secondary roll 18 or the take-up roll 20 is adjusted as necessary based on the tension detected by the tension pickup rolls 19a and 19b.

In order to prevent wrinkles, distortions, non-uniform adhesion and compression in the above processing steps, the elongated support 21 is formed.
The tension applied to is usually 20 to 2000 g / cm. The tension applied to the elongated phosphor sheet 22 is generally in the range of 10 to 700 g / cm.
In order to improve the flatness of the support, higher tension than that of the phosphor sheet is usually applied to the support. The tension applied to the laminated body 23 is generally 20 to 1500 g.
/ Cm range. In order to suppress the vibration due to expansion and contraction of the support body, the difference between the tension when the support body 21 is sent out and the tension when the laminated body 23 is wound is 20 to 1500 g.
It is preferably in the range of / cm. Note that these tensions may vary depending on the material and thickness of the support and the phosphor sheet.

In order to suppress the vibration of the support (and the laminate), the diameter of the support delivery roll 11 is generally in the range of 100 to 2000 mm, and the diameter of the laminate winding roll 20 is 100 to 2000 mm. Is in the range.

The apparatus used in the method of the present invention is not limited to the apparatus shown in FIGS. For example, the means for controlling the moment of inertia of the support delivery roll 11 is not limited to the mounting of the flywheel 33, and the moment of inertia is set by setting the weight or diameter of the shaft center 32 itself to a suitable range. It is possible to use any other means as long as it is within the range. Also, fluctuation (decrease) in the winding diameter of the delivery roll 11
Corresponding to the above, it is possible to provide the device with a function of changing the additional weight of the flywheel 33 in the middle of the calendar processing step. Alternatively, a flywheel may be mounted on the phosphor sheet delivery roll 13 and / or the laminate winding roll 20 to control the moment of inertia of the flywheel within a certain range.

A protective layer may be provided on the surface of the phosphor layer obtained by the above-mentioned calendar treatment, for the convenience of handling the radiation image conversion panel and for avoiding a change in characteristics. The protective layer is preferably transparent so that it hardly affects the incidence of excitation light or the emission of emitted light, and also sufficiently protects the radiation image conversion panel from external physical impact and chemical influences. In order to be able to do so, it is desirable to be chemically stable and have high physical strength.

As the protective layer, a solution prepared by dissolving a transparent organic polymer substance such as a cellulose derivative, polymethylmethacrylate, or an organic solvent-soluble fluororesin in an appropriate solvent is applied on the phosphor layer. Formed on the surface of the phosphor layer by using a suitable adhesive agent or an inorganic compound, or a sheet for forming a protective layer such as an organic polymer film such as polyethylene terephthalate is separately formed. What was formed into a film on the fluorescent substance layer by vapor deposition etc. is used. Further, in the protective layer, magnesium oxide, zinc oxide, titanium dioxide, light-scattering fine particles such as alumina, perfluoroolefin resin powder,
Various additives such as a lubricant such as a silicone resin powder and a crosslinking agent such as polyisocyanate may be dispersed and contained. The layer thickness of the protective layer is generally in the range of about 0.1 to 20 μm when it is made of a polymer material.

The surface of the protective layer may be further provided with a fluororesin coating layer in order to enhance the stain resistance of the protective layer. The fluororesin coating layer can be formed by applying a fluororesin solution prepared by dissolving (or dispersing) a fluororesin in an organic solvent onto the surface of the protective layer and drying.
Although the fluororesin may be used alone, it is usually used as a mixture of the fluororesin and a resin having high film forming property. Further, an oligomer having a polysiloxane skeleton or an oligomer having a perfluoroalkyl group can be used together. The fluororesin coating layer may be filled with a fine particle filler in order to reduce interference unevenness and further improve the quality of a radiation image. The layer thickness of the fluororesin coating layer is usually in the range of 0.5 μm to 20 μm. In forming the fluororesin coating layer, an additive component such as a cross-linking agent, a hardener, an anti-yellowing agent, etc. can be used. In particular, the addition of the crosslinking agent is advantageous for improving the durability of the fluororesin coating layer.

Although the radiation image conversion panel according to the present invention is obtained as described above, the configuration of the panel of the present invention may include various known variations. For example, for the purpose of improving the sharpness of the obtained image, at least one of the layers may be colored with a coloring agent that absorbs excitation light and does not absorb emitted light.

[0047]

Examples [Example 1] (1) Preparation of support Film-forming resin: soft acrylic resin (Chriscoat P-1018GS [20% toluene solution], Dainippon Ink and Chemicals, Inc.) 180g light reflection Material: Gadolinium oxide (Gd ₂ O ₃ ) fine particles (90% by weight of particles: 1 to 5 μm) 35 g Plasticizer: Phthalates (# 10, Daihachi Chemical Co., Ltd.) 4 g Conductive agent: Zinc oxide whiskers (Panatetra A-1-1, manufactured by Matsushita Amtec Co., Ltd.) 12 g Colorant: Ultramarine blue (SM-1, manufactured by Daiichi Kasei Co., Ltd.) 0.5 g

The material having the above composition was added to methyl ethyl ketone and mixed and dispersed using a propeller mixer to give a viscosity of 0.2.
A coating liquid for undercoat layer of 0.3 Ps was prepared. This coating solution was applied to a support (barium sulfate-kneaded polyethylene terephthalate sheet, thickness: 250 μm, Melinex # 335, ICI) provided with a light-shielding layer (layer thickness: about 1 μm) made of carbon black, silica and the above resin on one surface
Co., Ltd.) on the opposite surface, and dried to form an undercoat layer (layer thickness:
20 μm) was formed. This was wound around a roll to obtain a long-sized support having a light-shielding layer on one surface and an undercoat layer on the other surface.

(2) Preparation of phosphor sheet Photostimulable phosphor: Tetrahedral BaF (Br _0.85 I _0.15 ): Eu ²⁺ 10000 g Binder: Polyurethane elastomer (Pandex T-5265H [solid] dissolved in methyl ethyl ketone) Solid concentration 13% by weight, Dainippon Ink and Chemicals Co., Ltd. 2462g Crosslinking agent: Polyisocyanate (Coronate HX [solid content 100%], Nippon Polyurethane Industry Co., Ltd.) 30g Yellowing prevention Agent: Bisphenol A type epoxy resin (Epicoat # 1001 [solid], Yuka Shell Epoxy Co., Ltd.) 150 g

Methyl ethyl ketone 69
In addition to 0 g, a dispersing machine (10 L: 140 mm diameter cross blade) was used to mix and disperse at 2500 rpm for 1 hour to prepare a coating solution having a viscosity of 30 Ps (binder: phosphor (weight ratio) = 1: 20). . Half of this coating solution was uniformly applied with a width of 400 mm to the surface of a temporary support (polyethylene terephthalate sheet coated with a silicone-based release agent, thickness: 190 μm) with a Giesser solution, and after drying, A long phosphor sheet wrapped around a roll (thickness: 300
μm) was obtained.

(3) Heat and pressure treatment The above long support and phosphor sheet were loaded into a calendar treatment apparatus as shown in FIGS. 1 and 2, and heat and pressure were applied under the following treatment conditions. The treatment was performed to provide a stimulable phosphor layer on the support and to compress the phosphor layer.

Roll for feeding support: Moment of inertia: 1.0 kg · m ² Roll diameter: 300 mm Tension for feeding support: 600 g / cm Tension for feeding phosphor sheet: 40 g / cm Temporary support Tension for winding: 25g / cm Laminated body Tension during winding: 250g / cm Primary roll (metal roll pair, diameter: 200mm) Upper roll temperature: 70 ° C Lower roll temperature: 60 ° C Effective pressure: 30MPa Feed rate: 3m / min Secondary Roll (metal roll pair, diameter: 300 mm) Upper roll temperature: 75 ° C. Lower roll temperature: 40 ° C. Effective pressure: 35 MPa Feed rate: 3 m / min

(4) Attaching a protective layer An unsaturated polyester resin solution (Vylon 30SS, manufactured by Toyobo Co., Ltd.) was applied to the surface of a polyethylene terephthalate film having a thickness of 6 μm, and dried to form an adhesive layer (adhesive application). Weight: 2 g / m ² ). After laminating this film on the stimulable phosphor layer through an adhesive layer using a laminating roll, an emboss pattern is attached to the film surface,
A protective layer (surface roughness Ra: 0.2 μm) was provided. Thus, according to the method of the present invention, a radiation image conversion panel composed of the light-shielding layer, the support, the undercoat layer, the stimulable phosphor layer and the protective layer was produced.

[Embodiment 2] A radiation image conversion panel according to the present invention was prepared in the same manner as in Embodiment 1 except that the inertial moment of the support feeding roll was changed to 3.0 kg · m ^2. Manufactured.

[Embodiment 3] A radiation image conversion panel according to the present invention was manufactured in the same manner as in Embodiment 1, except that the moment of inertia of the support feeding roll was changed to 10 kg · m ² . .

[Comparative Example 1] A comparative example was carried out in the same manner as in Example 1 except that the flywheel was not attached to the support feeding roll and the inertia moment was changed to 0.2 kg · m ² . A radiation image conversion panel for was manufactured.

[Evaluation of Performance of Radiation Image Conversion Panel] The image unevenness of each obtained radiation image conversion panel was evaluated as follows. In addition, during the panel manufacturing, the unevenness of the feeding speed of the support in the calendering process was measured online.

After irradiating the surface of the radiation image conversion panel with a tungsten tube and an X-ray (about 10 mR) with a tube voltage of 80 kVp, a semiconductor laser beam having a wavelength of 660 nm was applied so that the excitation energy on the panel surface was 8 J / m ^2. The photostimulable luminescent light emitted from both front and back surfaces of the panel was received by a light receiver (photomultiplier tube with spectral sensitivity S-5) and converted into an electric signal to obtain a radiation image. The presence or absence of image unevenness in the obtained radiation image was visually determined. The obtained results are summarized in Table 1.

[0059]

[Table 1]                                 Table 1 ────────────────────────────────────   Example Support uneven feed speed Image unevenness ────────────────────────────────────   Example 1 There is slight vibration of 9 to 10 Hz, which is not observed   Example 2 There is slight vibration of 5 to 6 Hz, which is not observed   Example 3 Strong vibration of 5 to 6 Hz Not observed ────────────────────────────────────   Comparative Example 1 Corresponding to strong vibration of 9 to 10 Hz, 9 to 10 Hz                                                     Visualize image unevenness ────────────────────────────────────

As is clear from the results in Table 1, the radiation image storage panels manufactured according to the method of the present invention (Examples 1 to 3) were compared with the radiation image storage panels for comparison (Comparative Example 1). Thus, the vibration of the support was reduced, and as a result, a good radiation image without image unevenness was obtained. On the other hand, in the radiation image conversion panel for comparison, the vibration of the support was strong, and the obtained image had image unevenness.

[0061]

According to the manufacturing method of the present invention, the length of the support long body can be made long by controlling the inertia moment of the roll within a certain range by attaching a flywheel to the support delivery roll. Also, it is possible to effectively suppress the vibration of the support and the laminated body, and it is possible to prevent uneven rotation speed of the roll and uneven compression of the phosphor layer due to the uneven rotation speed. That is, the calendering treatment can be stably carried out even if the elongated support is long. Further, since the applicable pressure range of the calendar roll can be widened, it is possible to freely set the pressure according to the purpose. Further, since it is possible to prevent unevenness in the packing density of the phosphor, the radiation image conversion panel manufactured by using the manufacturing method of the present invention can give a radiation image without image defects such as image unevenness. .

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a calendar processing apparatus used in a manufacturing method of the present invention.

2 is a schematic side view of a support delivery roll provided in the apparatus of FIG. 1. FIG.

[Explanation of symbols]

11 Support delivery roll 13 Phosphor sheet delivery roll 15 Temporary support winding roll 17 Primary Calendar Roll 18 Secondary Calendar Roll 20 Laminate roll 31 roll body 32 roll axis 33 flywheel

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroki Saito             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. F term (reference) 2G083 AA03 BB01 CC02 CC04 EE02

Claims (8)

[Claims] 1. A method for producing a long body of a radiation image conversion panel having a phosphor layer on a support, comprising a delivery roll whose moment of inertia is controlled within a range of 0.5 to 20 kg.m ^2. , A long support is fed under tension, while a long phosphor sheet made of a phosphor and a binder is fed out under tension from another feed roll, and the support and the By stacking the phosphor sheet and pressing it under heating with a calendar roll, the phosphor sheet is adhered to form a phosphor layer on the support, and at the same time, the phosphor layer is compressed, and then the phosphor layer is pressed. A method comprising winding a support provided with a layer with a winding roll under tension. ^2. The method of manufacturing a radiation image conversion panel according to claim 1, wherein the moment of inertia of the support delivery roll is controlled within a range of 0.5 to 10 kg · m ² . 3. The method of manufacturing a radiation image conversion panel according to claim 1, wherein a flywheel is mounted on a fixed shaft of the support delivery roll to control the moment of inertia of the delivery roll. 4. The method for producing a radiation image conversion panel according to claim 1, wherein the difference between the tension when the support is fed out and the tension when the support is wound is 1000 g / cm or less. . 5. The method of manufacturing a radiation image conversion panel according to claim 1, wherein the diameter of the support delivery roll is in the range of 100 to 2000 mm. 6. The method for manufacturing a radiation image storage panel according to claim 1, wherein the diameter of the support take-up roll is in the range of 100 to 2000 mm. 7. The method of manufacturing a radiation image storage panel according to claim 1, wherein the elastic modulus of the elongated support is in the range of 1000 to 10000 MPa. 8. The method of manufacturing a radiation image storage panel according to claim 1, wherein the elastic modulus of the elongated phosphor sheet is in the range of 50 to 500 MPa.