JP2001133598A - Radiological image converting panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiological image converting panel excellent in durability, a flaw-proof property and an anti-foul property. SOLUTION: In this radiological image converting panel 40 having a support 3, a phosphor layer 1 formed of stimulable phosphor, which is laminated on the support 3, a resin film 5 laminated on the phosphor layer 1 and a protective layer (4-6) formed by a hard coat film 4 and an anti-foul film 6, the light transmissivity of the stimulation luminescent light and stimulating light having wavelength of 400 nm to 900 nm in the protective layer (4-6) is 90% to 100%, and the pencil hardness of the protective layer (4-6) is 2H or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation image conversion panel used for a radiation image conversion method using a stimulable phosphor.

[0002]

2. Description of the Related Art As an alternative to the conventional radiographic method, for example, a radiation image conversion method using a stimulable phosphor as described in JP-A-55-12145 is known. This method uses a radiation image conversion panel (a stimulable phosphor sheet) containing a stimulable phosphor, and transmits radiation transmitted through a subject or emitted from a subject to the stimulable phosphor of the panel. By absorbing the radiation energy stored in the stimulable phosphor in the form of fluorescence (excitation light) by time-sequentially exciting the stimulable phosphor with visible or infrared electromagnetic waves (excitation light) The fluorescent light is emitted as photostimulated light, the fluorescence is read photoelectrically to obtain an electric signal, and a radiation image of a subject or a subject is reproduced as a visible image based on the obtained electric signal. The panel after reading is prepared for the next photographing after the remaining image is erased. That is, the radiation image conversion panel is used repeatedly.

According to this radiographic image conversion method, a radiographic image with a large amount of information can be obtained with a much smaller exposure dose than the radiographic method using a combination of a conventional radiographic film and an intensifying screen. There is an advantage that it can be obtained. Furthermore, in contrast to the conventional radiographic method, which consumes radiographic film for each photographing, the radiographic image conversion method uses the radiographic image conversion panel repeatedly, which is advantageous in terms of resource conservation and economic efficiency. It is.

The radiation image conversion panel used in the radiation image conversion method has, as a basic structure, a support and a stimulable phosphor layer provided on the surface of the support. However,
When the phosphor layer is self-supporting, a support is not necessarily required. The stimulable phosphor layer usually comprises a stimulable phosphor and a binder containing and supporting the stimulable phosphor in a dispersed state. However, there is also known a stimulable phosphor layer which does not include a binder formed by a vapor deposition method or a sintering method and is composed of only an aggregate of the stimulable phosphor. Further, there is known a radiation image conversion panel having a stimulable phosphor layer in which a polymer substance is impregnated in a gap between stimulable phosphor aggregates.
In any of these phosphor layers, the stimulable phosphor has a property of exhibiting stimulable emission when irradiated with excitation light after absorbing radiation such as X-rays. Radiation emitted from the specimen is absorbed by the stimulable phosphor layer of the radiation image conversion panel in proportion to the radiation dose, and a radiation image of the subject or the subject is formed on the panel as an accumulated image of radiation energy. . This accumulated image can be emitted as stimulated emission light by irradiating the excitation light, and the accumulated image of radiation energy is imaged by photoelectrically reading the stimulated emission light and converting it into an electric signal. It is possible to do.

[0005] A protective layer is usually provided on the surface of the stimulable phosphor layer (the surface not facing the support) to protect the phosphor layer from chemical alteration or physical impact. are doing. The protective layer is formed by applying a solution prepared by dissolving a transparent organic polymer substance such as a cellulose derivative or polymethyl methacrylate in an appropriate solvent onto the phosphor layer, or polyethylene. An organic polymer film such as terephthalate or a sheet for forming a protective film such as a transparent glass plate is separately formed and provided on the surface of the phosphor layer using an appropriate adhesive, or an inorganic compound is deposited on the phosphor by vapor deposition or the like. Those formed on a layer are known.

Of these, organic polymer films and resin coatings are more flexible than glass plates and those obtained by vapor-deposition of inorganic compounds, and a protective film formed by laminating an organic polymer sheet on a phosphor layer. Layers generally have the advantage of high strength. Further, since the organic polymer film and the resin coating film are formed by applying and drying the coating material for forming the protective film on the phosphor layer, they have an advantage that they can be manufactured by a relatively simple process.

In the practice of the radiation image conversion method, the radiation image conversion panel emits radiation (records a radiation image), irradiates excitation light (reads a recorded radiation image), and irradiates erasing light (remains). It is repeatedly used in a cycle of “erasing a radiation image”. The transfer of the radiation image conversion panel to each step is performed by a conveying means such as a belt or a roller. After one cycle, the panels are usually stacked and stored. However, when the radiation image conversion panel having the protective layer formed by coating as described above is repeatedly used, the radiation image conversion panel is formed on the radiation image conversion panel because, for example, abrasion occurs on the surface of the protective layer. The quality of radiographic images tends to gradually decrease. Since it is desired that the radiation image conversion panel also provides an image having high sensitivity and good image quality (sharpness, granularity, etc.), similarly to the conventional radiographic method, it is desired that the above-mentioned scratches Preventing occurrence is a very important issue.

As a radiation image conversion panel having a coating film capable of preventing a decrease in sensitivity of the radiation image conversion panel due to repeated use as described above, the present applicant has already formed a coating film containing a fluorine-based resin soluble in an organic solvent. Image conversion panel having a protective layer (see JP-A-2-193100)
No.). The formation of an inorganic compound on the surface of a protective layer is known from Japanese Patent Publication No. 6-52320. However, a coating film containing a fluorine resin is not always at a satisfactory level in hardness, and it is industrially difficult to uniformly form a layer made of an inorganic compound over a relatively large area such as a panel. Since the flexibility of the obtained layer was not sufficient, it could not be said that the durability in repeated use for many times (long term) was sufficient.

[0009]

As described above, due to repeated use of the panel, the surface of the protective layer of the radiation image storage panel repeatedly comes into contact with the surface of another object, and as a result, abrasion occurs on the surface of the protective layer. This abrasion tends to cause the deterioration of the finally obtained radiation image or the deterioration of the quality of image information related to the radiation image.

The present invention has been made in view of such circumstances, and aims at improving the scratch resistance of the protective layer surface by repeated use of the panel, and having sufficient flexibility from the viewpoint of durability in repeated use. It is an object to provide a radiation image conversion panel.

[0011]

The radiation image conversion panel of the present invention comprises a phosphor layer comprising at least a stimulable phosphor,
In a radiation image conversion panel having a protective layer composed of an organic resin film laminated on the phosphor layer, the protective layer has a light transmittance of 90% to 100% for stimulated emission light and excitation light having a wavelength of 400 nm to 900 nm. Wherein the pencil hardness of the protective layer is 2H or more.

The wavelength of the protective layer is from 400 nm to 900 n.
m has a light transmittance of 90% for stimulated emission light and excitation light.
To 100%, particularly preferably 92% to 100%.

The pencil hardness means a hardness measured by a so-called pencil scratch resistance test for examining hardness by scratching the surface of a film using pencils having different hardnesses. The pencil hardness of the protective layer of the present invention is preferably 2H or more, particularly preferably about 3H to 6H.

The protective layer is desirably made of a high-hardness resin film. What is high hardness of high hardness resin film?
A resin film having a pencil hardness of 2H or more, especially about 3H to 6H, for example, a methacryl resin (PMMA), a tricyclodecane resin (trade name: AR)
TON, manufactured by JSR Corporation).

[0015] The protective layer may be formed of a hard coat film. The hard coat film is a film in which ultra-hard particles having a high hardness are dispersed in a transparent resin film. The ultra-fine particles having a high hardness have a Mohs hardness of 5 or more, a particle size of 0.5 μm or less, and further 0.2 μm. The following are preferred. For example, fine particles having no characteristic absorption in the visible light region, such as silica particles, silica sol, alumina particles, and alumina sol are preferable. PMM is a transparent resin containing fine particles.
In addition to A and PC, a radiation-curable resin, a two-pack curable resin, a fluorine-containing resin, and the like can be used. The content of the fine particles in the resin is 10 to 80 wt% by weight, and more preferably 30 to 80 wt%.
~ 60 wt% is preferred. In addition, the transparent resin has a wavelength of 4
A resin having a light transmittance of 90% to 100% for stimulated emission light and excitation light of 00 nm to 900 nm,
Hereinafter, the term transparent resin is used in this sense.

Further, a resin film may be further provided on the phosphor layer side of the hard coat film. As the resin film, polyethylene terephthalate (PE
General transparent resin films such as T), polycarbonate (PC), and triacetyl cellulose (TAC) can be used.

It is preferable that each of the high hardness resin film and the hard coat film has an antifouling film on its surface. The antifouling film is a layer for preventing contamination of the surface of the radiation image conversion panel, and is preferably a film made of a fluorinated resin, and a radiation-curable fluorinated resin or a thermosetting fluorinated resin soluble in a solvent. Particularly preferred for construction.

The protective layer has a thickness of 0.5 μm to 15 μm.
μm, more preferably 1 μm to 10 μm.
m is preferred.

The protective layer of the radiation image storage panel of the present invention may contain a cross-linking agent, a hardening agent, an anti-yellowing agent, and the like. In order to increase the durability of the protective layer, it is preferable to use a cross-linked material.

[0020]

According to the radiation image conversion panel of the present invention, there is provided a radiation image conversion panel having at least a phosphor layer composed of a stimulable phosphor and a protective layer composed of an organic resin film laminated on the phosphor layer. 400 nm to 900 wavelength of protective layer
90% light transmittance for stimulated emission light and excitation light
And the pencil hardness of the protective layer is set to 2H or more, so that even if the surface of the protective layer of the radiation image storage panel comes into contact with the surface of another object due to repeated use of the panel, scratches are less likely to occur, and It is possible to reduce the deterioration of the radiation image due to the abrasion or the deterioration of the quality of the image information related to the radiation image.

In the case of a protective layer in which an inorganic compound is applied to the surface of a radiation image storage panel, the flexibility of the radiation image storage panel cannot be said to be sufficient even if the protective layer is rich in scratch resistance. Although there was a problem in durability in use, the protective layer of the radiation image conversion panel of the present invention uses an organic resin film having sufficient flexibility, so that the radiation image conversion panel has sufficient durability. It can be a panel.

When the protective layer further includes an antifouling film, a radiation image conversion panel having antifouling properties in addition to the above-described scratch resistance and durability can be obtained.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A radiation image conversion panel according to the present invention will be described with reference to the drawings. 1 to 4 are cross-sectional views of a radiation image conversion panel according to an embodiment of the present invention.
The radiation image conversion panel of the present invention has at least a phosphor layer made of a stimulable phosphor and a protective layer made of an organic resin film, but the phosphor layer also has a function as a support. Apart from this, in a normal radiation image conversion panel, a support is provided on the back surface of the phosphor layer opposite to the side on which the protective layer is provided, and this will be described as an example.

The radiation image conversion panel 10 shown in FIG. 1 is formed by laminating a protective layer composed of a phosphor layer 1 and a high hardness resin film 2 on a support 3. The protective layer may be one in which an antifouling film is further provided on the high hardness resin film 2. The radiation image conversion panel 20 shown in FIG.
The protective layer includes a phosphor layer 1 and a hard coat film 4 laminated on a support 3. The protective layer may be one in which an antifouling film is further provided on the hard coat film 4. The radiation image conversion panel 30 shown in FIG. 3 is formed by laminating a protective layer composed of a phosphor layer 1, a resin film 5 and a hard coat film 4 on a support 3. FIG.
The radiation image conversion panel 40 shown in FIG. 5 is obtained by further laminating the antifouling film 6 on the hard coat film 4 of the radiation image conversion panel 30 shown in FIG.

The high-hardness resin film or the like serving as a protective layer may be formed by applying a coating solution capable of forming these protective layers on the phosphor layer, or separately forming these protective layers. Then, pressure may be applied to the surface of the phosphor layer using an appropriate adhesive. For example, in the former method, a coating solution for the protective layer is applied onto the phosphor layer (if a film has already been formed on the phosphor layer), dried, and then cured if necessary. Formed. In the latter case, for example, a heat-sensitive adhesive layer such as a soft acrylic type or a soft polyester type is provided on the side (back surface) of the protective layer in contact with the phosphor layer, which is in contact with the phosphor layer, and is thermally bonded to the phosphor layer. Can be formed. When an antifouling film for preventing contamination is further provided, it may be coated, dried, and cured separately from the high-hardness resin film or the like, or may be simultaneously coated, dried, and cured.

The radiation-curable resin that can be used as the transparent resin of the hard coat film is a resin containing a prepolymer which is a radiation-curable composition and is suitable for use, for example, an unsaturated resin such as polyester acrylate. Preferred are polyesters, urethane-modified unsaturated polyesters such as urethane-polyester acrylate, and liquid polyesters having an acrylic group as a terminal group. As an unsaturated copolyester having an acrylic terminal group,
European Patent Publication No. 207257 and Radia
t. Phys. Chem. Vol.33, No.5,443 ~
450 (1989). The latter liquid copolyester does not contain low molecular weight unsaturated monomers and other volatiles and is of very low toxicity (th
e journal Adhasion 1990 He
ft 12, page 12). The manufacture of a wide variety of radiation-curable acrylic polyesters is from German Offen
Lengungsschrift No.2838691
Are disclosed. Further, a mixture of two or more prepolymers may be used. The UV curable coating composition comprises:
For example, the journal "Coating" 9 /
88, pp. 348-353.

When the radiation curing is carried out by ultraviolet radiation (UV), a photoinitiator is present in the composition of the protective film to polymerize the monomer and to crosslink the prepolymer and the prepolymer for curing the protective film composition. Preferably act as a catalyst for initiating the reaction. Also, a photosensitizer may be present to promote the effect of the photoinitiator.

Suitable photoinitiators for the UV curable coating composition include organic carbonyl compounds, for example, benzoin ether compounds such as benzoin isopropyl and isobutyl ether, benzyl ketal compounds such as ketoxime esters, benzophenone, o- Benzophenone compounds such as benzoylmethylbenzoate, for example, acetophenone, trichloroacetophenone, 1,1-
Acetophenone-based compounds such as dichloroacetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, for example, 2-chlorothioxanthone, 2-ethylthioxanthone; and 2-
Thioxanthone compounds such as hydroxy-2-methyl-propiophenone, 2-hydroxy-4'-isopropyl-2-methylpropiophenone, and 1-hydroxycyclohexylphenyl ketone are preferred.

A particularly preferred photoinitiator is 2-hydroxy-
2-methyl-1-phenyl-propan-1-one, which is trade name DAROCUR 1173,
E. of Darmstadt, Germany Commercially available from Merck. The aforementioned photopolymerization initiators can be used alone or as a mixture of two or more. Examples of suitable photosensitizers include, for example, British Patent 1,314,556, British Patent 1,486,911, US Pat. No. 4,255.
There are certain aromatic amino compounds as described in US Pat. No. 513, and merocyanine and carbostyril compounds as described in US Pat. No. 4,282,309.

The fluororesin which can be used for the transparent resin of the hard coat film or the antifouling film is a resin composition containing a fluorine resin which is soluble in an organic solvent. Copolymers containing coalesced or fluorine-containing olefins as copolymer components are preferred.

In order to improve the hardness and scratch resistance and to improve and adjust the luminous performance, these protective layers may be added with inorganic or organic particles, lubricants, coloring agents, etc. in addition to the polymer resin. Is also good.

The inorganic particles preferably have no significant absorption band between 400 nm and 900 nm.
Silica and the like are preferred. As organic particles, melamine resin particles, benzoguanamine resin particles, silicone resin particles,
Fluororesin particles, cured acrylic resin powder, polyester resin powder, and the like are preferred. Particle size from 5 nm to 1
It is preferably 00 μm, more preferably about 10 nm to 5 μm.

As the lubricant, a fluorine-based surfactant,
Fluorine-based oils, modified polysiloxane-based oils, perfluoroalkyl group-containing polysiloxane oils and the like are preferred, and the content is preferably 0.01 to 10% by weight in the protective layer or on the surface.

As the fluorine-based surfactant, a perfluoroalkyl group-containing oligomer is preferable. Specifically, Megafac series manufactured by Dainippon Ink and Chemicals, Inc., particularly, F-110, F-116, and F-series 120, F-142
D, F-144D, F-150, F-160, F-17
1, F-172, F-173, F-177, F-178
A, F-178K, F-179, F-183, F-18
4, F-191, F-812, etc., Surflon series manufactured by Asahi Glass Co., Ltd., especially S-381, S-383, S-
393, SC-101, SC-105, KH-40, etc.
FC series manufactured by Sumitomo 3M Co., Ltd., especially FC-430, F
C-431 and the like are preferred. As the fluorinated oil, Daifoil manufactured by Daikin Industries, Ltd. is preferable. Specific examples of perfluoroalkyl group-containing polysiloxane oils include X-22-819 and X-22 manufactured by Shin-Etsu Silicone Co., Ltd.
-820, X-22-821, X-22-822, FL
100, FS1265 manufactured by Toray Silicone Co., Ltd., and FQF501 manufactured by Toshiba Silicone Co., Ltd. are preferable.

Next, the fluorescence of the radiation image conversion panel of the present invention will be described.
The stimulable phosphor constituting the body layer will be described. Photostimulable firefly
The light body is irradiated with radiation as described above,
Is a phosphor that shows stimulated emission when irradiated
Excitation light whose wavelength is in the range of 400 to 900 nm
Shows stimulated emission in the wavelength range of 300 to 500 nm
It is desirable that the phosphor be a phosphor. Radiation image conversion of the present invention
Examples of stimulable phosphors used in panels include U.S.
No. 3,859,527, SrS: Ce,
Sm, SrS: Eu, Sm, ThO₂: Er and L
a₂O₂S: Eu, Sm, JP-A-55-12142
ZnS: Cu, Pb, BaO xAl₂O₃: Eu
(Provided that 0.8 ≦ x ≦ 10) and M^IIO xSi
O₂: A (however, M^IIIs Mg, Ca, Sr, Zn,
Cd or Ba, A is Ce, Tb, Eu, Tm,
Pb, Tl, Bi, or Mn, and x is 0.5 ≦
x ≦ 2.5) described in JP-A-55-12143.
(Ba_1-xy, Mg_x, Ca_y) FX: aEu
²⁺(Where X is at least one of Cl and Br)
X and y are 0 <x + y ≦ 0.6 and x
y ≠ 0 and a is 10^-6≦ a ≦ 5 × 10^-2In
LnOX: xA described in JP-A-55-12144.
(However, Ln is La, Y, Gd, and Lu
X is at least one of Cl and Br
And A is at least one of Ce and Tb;
And x is 0 <x <0.1).
(Ba) described in No. 12145_1-x, M²⁺ _x) FX:
yA (where M²⁺Are Mg, Ca, Sr, Zn, and
And Cd, X is Cl, Br and
At least one of I, A is Eu, Tb, Ce, T
m, Dy, Pr, Ho, Nd, Yb, and Er
And x is 0 ≦ x ≦ 0.6, y
Is 0 ≦ y ≦ 0.2).
M described in No. 8^IIFX xA: yLn (where M
^IIIs Ba, Ca, Sr, Mg, Zn, and Cd
A is BeO, MgO, CaO, S
rO, BaO, ZnO, Al₂O₃, Y₂O₃, La₂
O₃, In₂O₃, SiO₂, TiO₂, ZrO₂, G
eO₂, SnO₂, Nb₂O₅, Ta₂O₅, And T
hO₂At least one of Ln is Eu, Tb,
Ce, Tm, Dy, Pr, Ho, Nd, Yb, Er, S
at least one of m and Gd, X is Cl, B
r and at least one of I, x and
y is 5 × 10 each^-5≦ x ≦ 0.5 and 0 <y ≦
0.2) and a phosphor represented by the composition formula
No. 6-116777, (Ba)_1-x, M^II _x)
F₂ ・ ABaX₂: YEu, zA (where M^IIIs
Beryllium, magnesium, calcium, strontium
At least one of zinc, cadmium,
X is at least one of chlorine, bromine and iodine
The species, A, is a minor of zirconium and scandium.
A, x, y, and z are each
0.5 ≦ a ≦ 1.25, 0 ≦ x ≦ 1, 10^-6≦ y ≦ 2
× 10^-1, And 0 <z ≦ 10^-2Is the composition formula
Phosphors described in JP-A-57-23673.
(Ba_1-x, M^II _x) F₂ ・ ABaX ₂: YE
u, zB (where M^IIIs beryllium, magnesium
Calcium, strontium, zinc and cadmium
X is chlorine, bromine, and
At least one of urine, a, x, y, and
And z are 0.5 ≦ a ≦ 1.25, 0 ≦ x ≦ 1,
10^-6≦ y ≦ 2 × 10^-1, And 0 <z ≦ 2 × 10
^-1Phosphor represented by the composition formula
No. 23675 (Ba)_1-x, M^II _x) F₂ 
・ ABaX ₂: YEu, zA (where M^IIIs berili
Um, magnesium, calcium, strontium, sub
At least one of lead and cadmium, X is a salt
At least one of nitrogen, bromine and iodine, A is
At least one of arsenic and silicon, a,
x, y, and z are respectively 0.5 ≦ a ≦ 1.25, 0
≦ x ≦ 1, 10^-6≦ y ≦ 2 × 10^-1, And 0 <z
≦ 5 × 10^-1Is a phosphor represented by the composition formula:
M described in JP-A-58-69281^IIIOX: xC
e (however, M^IIIAre Pr, Nd, Pm, Sm, E
u, Tb, Dy, Ho, Er, Tm, Yb, and Bi
At least one trivalent metal selected from the group consisting of
X represents one of Cl and Br or
X is 0 <x <0.1)
Phosphor described in JP-A-58-206678.
Ba of_1-xM_{x / 2}L_{x / 2} FX: yEu²⁺(T
Where M is a group consisting of Li, Na, K, Rb and Cs
Represents at least one alkali metal selected from the group consisting of:
L is Sc, Y, La, Ce, Pr, Nd, Pm, S
m, Gd, Tb, Dy, Ho, Er, Tm, Yb, L
selected from the group consisting of u, Al, Ga, In, and Tl
Represents at least one trivalent metal; X is Cl,
At least one selected from the group consisting of Br and I
And x is 10^-2≦ x ≦ 0.
5, y is 0 <y ≦ 0.1).
Phosphor, BaFX • described in JP-A-59-27980.
xA: yEu²⁺(Where X is Cl, Br, and
At least one halogen selected from the group consisting of I
Yes; A is a calcined product of a tetrafluoroborate compound
And x is 10^-6≦ x ≦ 0.1, y is 0 <y ≦
0.1) and a phosphor represented by the composition formula
BaFX.xA: yEu described in 9-47289²⁺
(Where X is a group consisting of Cl, Br and I
A is at least one halogen selected;
Safluorosilicic acid, hexafluorotitanic acid and hex
Salts of monovalent or divalent metals of safluorozirconic acid
At least selected from the group consisting of hexafluoro compounds
Is also a calcined product of a compound; and x is 10^-6
≦ x ≦ 0.1, y is 0 <y ≦ 0.1)
Phosphors described in JP-A-59-56479.
BaFX xNaX ': aEu²⁺(However, X and
X ′ is at least one of Cl, Br and I, respectively.
X and a are each 0 <x ≦ 2, and
And 0 <a ≦ 0.2).
And M described in JP-A-59-56480.^IIFX ・ x
NaX ': yEu²⁺: ZA (where M^IIIs Ba,
At least one selected from the group consisting of Sr and Ca
X and X 'are each an alkaline earth metal of the species
At least one selected from the group consisting of Cl, Br, and I
A is V, Cr, Mn, F
at least one transition selected from e, Co, and Ni
And x is 0 <x ≦ 2, y is 0 <y ≦
0.2 and z is 0 <z ≦ 10^-2Is the composition formula
Phosphors described in JP-A-59-75200
M^IIFX ・ aM^IX'.bM '^IIX " ₂・ CM
^III X "'_ThreeXA: yEu²⁺(However, M^IIIs B
at least selected from the group consisting of a, Sr, and Ca
Is also a kind of alkaline earth metal;^IIs Li, Na,
At least selected from the group consisting of K, Rb, and Cs
Is also a kind of alkali metal;^IIIs Be and M
at least one divalent metal selected from the group consisting of
Yes; M^III Is from Al, Ga, In, and Tl
At least one trivalent metal selected from the group consisting of:
A is a metal oxide; X is from Cl, Br, and I
At least one halogen selected from the group consisting of:
X ', X "and X"' are F, Cl, Br, and I
At least one halogen selected from the group consisting of
A is 0 ≦ a ≦ 2, b is 0 ≦ b ≦ 10^-2,
c is 0 ≦ c ≦ 10^-2And a + b + c ≧ 10^-6In
X is 0 <x ≦ 0.5, y is 0 <y ≦ 0.2)
A phosphor represented by the following composition formula:
M in number^IIX₂・ AM^IIX '₂: XEu²⁺(T
But M^IIIs selected from the group consisting of Ba, Sr and Ca
At least one alkaline earth metal;
And X 'is selected from the group consisting of Cl, Br and I
At least one halogen and X'X ';
A is 0.1 ≦ a ≦ 10.0, x is 0 <x ≦ 0.2
Stimulable phosphor represented by the following formula:
M described in -101173^IIFX ・ aM^I X ': x
Eu²⁺(However, M^IIIs from Ba, Sr and Ca
At least one alkaline earth metal selected from the group consisting of
And M^I Is selected from the group consisting of Rb and Cs
X is Cl, B
at least one member selected from the group consisting of r and I
X 'consists of F, Cl, Br and I
At least one halogen selected from the group;
Where a and x are 0 ≦ a ≦ 4.0 and 0 <, respectively.
x ≦ 0.2) stimulable fluorescence represented by the composition formula:
And M described in JP-A-62-25189.^I X: xB
i (where MI is selected from the group consisting of Rb and Cs)
X is Cl,
At least one member selected from the group consisting of Br and I
Is halogen; and x is a number in the range 0 <x ≦ 0.2
Stimulable phosphor represented by the following composition formula:
LnOX: xCe described in 2-229882 (however,
Ln is at least one of La, Y, Gd, and Lu
X is at least one of Cl, Br and I
X is 0 <x ≦ 0.2, and the ratio between Ln and X is
0.500 <X / Ln ≦ 0.998, and
The maximum wavelength λ of the stimulable excitation spectrum is 550 nm <λ <
Cerium-activated rare earth oxyha represented by 900 nm)
And a logenide phosphor.

Note that the above-mentioned JP-A-60-84381 describes
M listed^IIX₂・ AM^IIX '₂: XEu²⁺Photostimulable firefly
The following additives are added to the light body.^IIX₂・ AM
^IIX '₂May be contained in the following proportions per mole
No. BM described in JP-A-60-166379^IX "
(However, M^I Is selected from the group consisting of Rb and Cs
X "is F,
At least selected from the group consisting of Cl, Br and I
A kind of halogen, and b is 0 <b ≦ 10.0
BKX "described in JP-A-60-221483.
・ CMgX "'₂・ DM^III X ""₃(However, M
^III Is a group consisting of Sc, Y, La, Gd and Lu
At least one trivalent metal selected, X ",
X "'and X" "are both from F, Cl, Br and I
At least one halogen selected from the group consisting of
And b, c and d are respectively 0 ≦ b ≦ 2.0, 0
≦ c ≦ 2.0, 0 ≦ d ≦ 2.0, and 2 × 10
^-5.Ltoreq.b + c + d); JP-A-60-228592.
YB (where y is 2 × 10^-4≦ y ≦ 2 ×
10^{− 1}Described in JP-A-60-228593.
BA (where A is SiO₂And P₂O₅Consists of
At least one oxide selected from the group; and
b is 10^-4≦ b ≦ 2 × 10^-1JP-A-61-61
BSiO described in JP-A-120883 (where b is 0 <
b ≦ 3 × 10^-2And JP-A-61-120885.
BSnX "₂ (However, X "is F, Cl,
At least one member selected from the group consisting of Br and I
Halogen and b is 0 <b ≦ 10^-3In
BCsX "described in JP-A-61-235486.
・ CSnX "' ₂ (However, X "and X" 'are each
At least one selected from the group consisting of F, Cl, Br and I
Are a kind of halogen, and b and c are
0 <b ≦ 10.0 and 10 respectively^-6≦ c ≦ 2 × 10
^-2And JP-A-61-235487.
BCsX "・ yLn³⁺(However, X "
At least one selected from the group consisting of F, Cl, Br and I
Ln is Sc, Y, Ce, P
r, Nd, Sm, Gd, Tb, Dy, Ho, Er, T
at least one selected from the group consisting of m, Yb and Lu
Is a kind of rare earth element, and b and y are each
0 <b ≦ 10.0 and 10^-6≦ y ≦ 1.8 × 1
0^-1Is).

Among the above stimulable phosphors, a divalent europium-activated alkaline earth metal halide-based phosphor and a cerium-activated rare earth oxyhalide phosphor are particularly preferred because they exhibit high-luminance stimulable emission. However, the stimulable phosphor used in the present invention is not limited to the above-described phosphors, and any phosphor can be used as long as it exhibits stimulable emission when irradiated with radiation and then irradiated with excitation light. There may be.

The stimulable phosphor layer of the radiation image storage panel of the present invention comprises not only a stimulable phosphor and a binder containing the stimulable phosphor in a dispersed state but also supporting the stimulable phosphor. It may be composed of only a stimulable phosphor aggregate or a phosphor layer in which a polymer substance is impregnated in a gap between the stimulable phosphor aggregates.

Next, the method for producing the radiation image storage panel of the present invention will be described by taking, as an example, a case where the phosphor layer comprises a stimulable phosphor and a binder containing and supporting the stimulable phosphor in a dispersed state.

The phosphor layer can be formed on a support by the following known method. First, a stimulable phosphor and a binder are added to a solvent and mixed well to prepare a coating solution in which the stimulable phosphor is uniformly dispersed in a binder solution. The mixing ratio between the binder and the stimulable phosphor in the coating solution varies depending on the characteristics of the intended radiation image conversion panel, the type of the phosphor, and the like. Generally, the mixing ratio between the binder and the phosphor is 1%. 1 to 1: 100 (weight ratio), particularly preferably from 1: 8 to 1:40 (weight ratio). The coating solution containing the phosphor and the binder prepared as described above is then uniformly applied to the surface of the support to form a coating film. This coating operation is performed by a normal coating means, for example, a doctor blade,
It can be performed by using a roll coater, a knife coater, an extrusion coater, or the like.

The support can be arbitrarily selected from materials known as supports for conventional radiation image conversion panels. In a known radiation image conversion panel, a phosphor layer is provided to enhance the bond between the support and the phosphor layer or to improve the sensitivity or image quality (sharpness, granularity) of the radiation image conversion panel. A polymer material such as gelatin is applied to the surface of the support on the side to form an adhesion-imparting layer, or a light-reflective layer made of a light-reflective material such as titanium dioxide, or a light-absorbent material such as carbon black It is known to provide an absorption layer or the like. The support used in the present invention can also be provided with these various layers, and the configuration thereof can be arbitrarily selected depending on the desired purpose and application of the radiation image storage panel. Further, JP-A-58-20020
As described in No. 0, in order to improve the sharpness of the obtained image, the surface of the support on the side of the phosphor layer (the surface of the support on the side of the phosphor layer, the adhesion imparting layer, the light reflecting layer, Alternatively, in the case where a light absorbing layer or the like is provided, the surface thereof means fine irregularities. After forming a coating on the support as described above, the coating is dried to complete the formation of the stimulable phosphor layer on the support. The thickness of the phosphor layer depends on the characteristics of the intended radiation image conversion panel, the kind of the phosphor, the mixing ratio of the binder to the phosphor, and the like, but is usually 20 μm to 1 mm.
More preferably, it is 0 to 500 μm. The stimulable phosphor layer does not necessarily need to be formed by directly applying a coating solution on the support as described above. For example, a separate sheet such as a glass plate, a metal plate, or a plastic sheet may be used. After forming a phosphor layer by applying a coating solution thereon and drying, the support and the phosphor layer may be joined by pressing the phosphor layer on a support or using an adhesive or the like. .

For the purpose of improving the sharpness of the obtained image, at least one of the layers constituting the radiation image conversion panel of the present invention absorbs excitation light,
The stimulated emission light may be colored by a colorant that does not absorb the light (see Japanese Patent Publication No. 54-23400). Examples will be described below.

Example Preparation of Phosphor Layer As a coating solution for forming a phosphor sheet, a tetrahedral phosphor (BaFBr _0.85 I _0.15 : Eu ²⁺ ) 1000 was used.
And a binder (polyurethane elastomer; Dainippon Ink and Chemicals, Inc., Pandex T-5265H)
(Solid)) was dissolved in methyl ethyl ketone (MEK) to obtain a solid content concentration of 13 wt%, and 246 parts of a crosslinking agent (polyisocyanate; Nippon Polyurethane Industry Co., Ltd.)
3 parts of Coronate HX (solid content 100%) and 15 parts of a yellowing inhibitor (epoxy resin; Yuka Shell Epoxy Co., Ltd., Epicoat # 1001 (solid)) were added to 69 parts of MEK, and the mixture was dissolved at 2400 rpm using a dissolver. After dispersing for 2 hours, a 30 Ps coating solution was prepared (weight ratio of binder / phosphor = 1/20). This coating solution is applied on a polyethylene terephthalate sheet (temporary support, thickness: 190 μm) to which a silicone release agent has been applied by an extrusion coater, dried, and then peeled off from the temporary support to obtain a phosphor sheet. (Sheet thickness: 200 μm, application width = 3
00 mm). The above operation was repeated to prepare a plurality of phosphor sheets.

Preparation of Support A solution prepared by dissolving Byron 300 (an unsaturated polyester resin manufactured by Toyobo Co., Ltd.) in MEK (solid content = 15 wt%)
In 100 parts, FS-10P MEK dispersion (SnO ₂ (Sb-doped) needle-like fine particles manufactured by Ishihara Sangyo Co., Ltd. (long axis =
(0.2 to 2 μm, short axis = 0.01 to 0.02 μm); solid content = 30 wt%) 56.4 parts and MEK 48 parts were added to prepare a liquid having a viscosity of about 0.3 ps, which was supported. Body (polyethylene terephthalate sheet (Toray Lumirror S-10 250 μm; haze degree (typical) = 2)
7)) was applied so as to have a thickness of 3 μm.

Heat Compression Treatment Using a calender, one of the phosphor sheets was overlaid so that the release surface layer at the time of application was in contact with the undercoat layer surface of the support, and a calender roll (φ200 mm; metal roll) was used. Thermal compression was performed at a total load of 1.6 tons, an upper roll temperature of 60 ° C., a lower roll temperature of 60 ° C., and a feed rate of 1 m / min.

Example 1 5 μm thick ARTON (JS
A polyester resin solution (Toyobo Co., Ltd., Byron 30SS) was applied to a film (pencil hardness 2H, manufactured by R Co., Ltd.) and dried to form an adhesive layer (adhesive application weight 2 g / m ² ). The ARTON film was adhered to the phosphor layer via an adhesive layer using a laminating roll, and then an emboss pattern was formed. Thereby, the surface roughness (Ra =
A 0.2 μm) protective layer (high-hardness resin film) was formed to prepare a panel.

Example 2 A fluororesin (fluoroolefin copolymer; JSR) was placed on a 6 μm-thick PET support sheet (Lumilar 6c-F53, Toray Industries, Inc.).
92.5 parts of Opstar JN7205 (30% MIBK solution), 5 parts of crosslinking agent (polyisocyanate; Sumitomo Bayer Urethane Co., Ltd., Sumidur N3500 (solid content 100%)), inorganic filler dispersion (Sumitomo) Chemistry
11 parts of AKP-50 manufactured by Co., Ltd., a silane coupling agent,
Shin-Etsu Chemical Co., Ltd .: 2 wt% KBM403, MIBK26
37 parts, a catalyst (dibutyltin dilaurate; Kyodo Yakuhin Co., Ltd., KS1260)
0.0004 parts, methyl isobutyl ketone (MIBK)
66.5 parts were added, and a hard coat film coating solution obtained by stirring with a dissolver was applied, and then dried and cured to a thickness of 2
A μm hard coat film was provided. Next, a polyester resin solution (Toyobo Co., Ltd., Byron 30SS) was applied and dried on the side opposite to the side on which the hard coat film was provided to form an adhesive layer (adhesive application weight 2 g / m ² ). This PET
The film was adhered to the phosphor layer via an adhesive layer using a laminate roll, and then an emboss pattern was formed. In this way, a protective layer (resin film + laminated hard coat film) having a surface roughness (Ra = 0.2 μm) was formed, and a panel was formed.

Example 3 A 6 μm thick PET support sheet (Lumirror 6c-F53, Toray Industries, Inc.)
PHA (dipentaerythritol hexaacrylate)
45 parts, inorganic filler (manufactured by Nissan Chemical Co., Ltd., MEK silica sol (solid content 30%), silane coupling agent, Shin-Etsu Chemical Co., Ltd .: 2 wt% added to KBM503 (solid content 100%) and reacted in advance. ) 92 parts, 127 parts of MEK were added, a hard coat film coating solution obtained by stirring with a dissolver was applied, dried, and then UV-cured with a high-pressure mercury lamp 1.0 J / cm ³ to form a 2 μm thick hard coat film. Provided. Next, a fluorine-based resin (fluoroolefin-based copolymer; JSR
92.5 parts of Opstar JN7205 (30% MIBK solution), 5 parts of crosslinking agent (polyisocyanate; Sumitomo Bayer Urethane Co., Ltd., Sumidur N3500 (solid content 100%)), catalyst (dibutyltin dilaurate; Kyodo Yakuhin, KS1260) 0.0004 parts,
66.5 parts of MIBK was applied at 1 g / m ² and dried, and 12
Cured at 0 ° C. Further, a polyester resin solution (Toyobo Co., Ltd. Byron 30SS) was applied on the side opposite to the side on which the hard coat film was provided, and dried to form an adhesive layer (adhesive application weight 2 g / m ² ). This PET film is
Using a laminating roll, an emboss pattern was formed after bonding to the phosphor layer via an adhesive layer. As a result, a protective layer (resin film +
A laminate type hard coat film + an antifouling film) was formed to prepare a panel.

Example 4 The hard coat film coating solution used in Example 2 was coated on the phosphor layer after the heat compression treatment with a coating thickness of 2 μm.
m, dried, and cured at 120 ° C., and then an embossed pattern was formed. Thus, a protective layer (coating type hard coat film) having a surface roughness (Ra = 0.2 μm) was formed, and a panel was formed.

(Example 5) The coating solution of the hard coat film used in Example 3 was coated on the phosphor layer after the heat compression treatment with a coating thickness of 2 μm.
m, and after drying, 1.0 J /
UV curing was performed at cm ³ to provide a hard coat film having a thickness of 2 μm. Further, the antifouling film coating solution used in Example 3 was applied thereon at 1 g / m ² , dried, and cured at 120 ° C.
Thereafter, an emboss pattern was applied. As a result, a protective layer (coating type hard coat film + antifouling film) having a surface roughness (Ra = 0.2 μm) was formed, and a panel was formed.

Example 6 5 g of a hydroxyl group-containing silicone oil X-22-2809 (about 66% solution manufactured by Shin-Etsu Silicone Co., Ltd.) as a lubricant was added to the hard coat film coating solution used in Example 2, and a melamine resin. Powder (Nippon Shokubai
18 g of Eposter S6 manufactured by Co., Ltd. and 0.3 g of dispersant (Plenact AL-M manufactured by Ajinomoto Co., Inc.) were added to prepare a coating solution, and a protective layer (coating type hard coat film + organic resin powder +
A panel was prepared in the same manner as in Example 2 except that a lubricant was formed.

(Comparative Example 1) ARTO used in Example 1
A panel was prepared in the same manner as in Example 1, except that a 6 μm-thick PET film (Lumirror 6c-F53, Toray Industries, Inc.) was used instead of the N film.

Comparative Example 2 An inorganic filler dispersion (AKP50 manufactured by Sumitomo Chemical Co., Ltd. was used as a silane coupling agent, Shin-Etsu Chemical Co., Ltd .: K) from the hard coat film coating solution used in Example 2.
A panel was prepared in the same manner as in Example 2 except that 2 wt% was added to BM403 (100% solids and reacted in advance).

(Comparative Example 3) An inorganic filler dispersion (MIBK silica sol (solid content: 30%) manufactured by Nissan Chemical Industries, Ltd., solid content: 30%) was used as a silane coupling agent from the hard coat film coating solution used in Example 4, and Shin-Etsu Chemical Co., Ltd. : KBM503 (solid content 100
%) Was prepared in the same manner as in Example 4 except that 2% by weight) was added and reacted in advance.

(Evaluation Experiment) Measurement of light emission intensity and sharpness After irradiating each of the above radiation image conversion panels with X-rays having a tube voltage of 80 KVp, He-Ne laser light (wavelength: 63)
(2.8 nm), and the stimulated emission of each panel was measured. The measurement result was evaluated as a relative value with Comparative Example 1 being 100%.

2. Pencil hardness Evaluation was made according to the pencil scratch resistance test method of JIS K5400.

3. Scratch resistance The scratch resistance of each protective layer surface was measured by the following method. First, the radiation image conversion panel was 25.2 cm x 3
The sample was cut into a rectangle of 0.3 cm to prepare a measurement sample. Next, PET used as a support of the radiation image conversion panel
The sample was placed on the sheet with the protective layer side of the sample down. In this state, the sample was repeatedly reciprocated 10,000 times in a stroke of 10 cm, and the support and the base sheet were rubbed. Then, the surface of the protective layer of the sample was visually observed and evaluated. The evaluation was performed based on the following four criteria.

A: Scratch scarcely occurred.

B: Some abrasion occurred, but no problem in practical use.

C: Many scratches occur.

D: Very many scratches occur.

4. Antifouling property The antifouling property of each protective layer surface was measured by the following method. First, the radiation image conversion panel was 25.2 cm x 3
The sample was cut into a rectangle of 0.3 cm to prepare a measurement sample. Next, the panel was repeatedly reciprocated 10,000 times with a rubber roller used in a radiation image converter in a stroke of 10 cm, and the panel and the rubber roller were rubbed. Then, the surface of the protective layer of the sample was visually observed and evaluated. The evaluation was performed based on the following four criteria.

A: Almost no dirt adhered.

B: Some dirt adhered, but no practical problem.

C: Many stains adhere.

D: Very large amount of dirt adhered.

Table 1 shows the results obtained by the above evaluation methods.

[0068]

[Table 1] As is clear from Table 1, the radiation image conversion panel having the protective layer having a pencil hardness of 2H or more is excellent in the anti-scratch property. A radiation image conversion panel having more excellent antifouling properties was obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a radiation image conversion panel according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a radiation image conversion panel according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a radiation image conversion panel according to a third embodiment of the present invention.

FIG. 4 is a sectional view showing a radiation image conversion panel according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Phosphor layer 2 High hardness resin film 3 Support 4 Hard coat film 5 Resin film 6 Antifouling film 10 Radiation image conversion panel

Claims (8)

[Claims] 1. A radiation image conversion panel having at least a phosphor layer composed of a stimulable phosphor and a protective layer composed of an organic resin film laminated on the phosphor layer, wherein the wavelength of the protective layer is from 400 nm to 900 nm. A light transmittance for stimulating light and excitation light of 90% to 100%, and a pencil hardness of the protective layer is 2H or more. 2. The radiation image conversion panel according to claim 1, wherein the pencil hardness of the protective layer is 3H to 6H. 3. The radiation image conversion panel according to claim 1, wherein the protective layer is made of a high-hardness resin film. 4. The radiation image conversion panel according to claim 3, wherein the high hardness resin film further has an antifouling film on a surface of the high hardness resin film. 5. The radiation image storage panel according to claim 1, wherein the protective layer is made of a hard coat film. 6. The radiation image conversion panel according to claim 5, wherein the hard coat film has a resin film on the phosphor layer side of the hard coat film. 7. The radiation image conversion panel according to claim 5, wherein the hard coat film further has an antifouling film on a surface of the hard coat film. 8. The protective layer has a thickness of 0.5 μm to 15 μm.
8. The method according to claim 1, wherein the thickness is μm.
Item 6. A radiation image conversion panel according to Item 1.