JPS59211900A - Radiation image conversion panel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radiation image conversion panel. More specifically, 1 the present invention provides a radiation image conversion panel comprising a support and a phosphor layer comprising a binder supporting the stimulable phosphor provided on the support in a dispersed state F; It is related to.

2. Description of the Related Art Conventionally, a so-called radiographic method has been used to obtain a radiographic image in the form of a combination of a radiographic film having an emulsion layer made of a silver salt photosensitive material and an intensifying screen. Recently, as an alternative to the radioradiography method, for example, U.S. Pat.
No. 859,527 specification and JP-A-55-12145
A radiation image conversion method using a stimulable phosphor, as described in the above publication, has attracted attention. This radiation image conversion method uses a radiation image conversion panel (stimulable phosphor sheet) containing a stimulable phosphor. The stimulable phosphor is absorbed by the stimulable phosphor, and then the stimulable phosphor is excited with electromagnetic waves (excitation light) selected from visible light and infrared rays in a time-series manner. Fluorescence (
The fluorescent light is emitted as stimulated luminescence (stimulated luminescence), this fluorescence is read photoelectrically to obtain an electrical signal, and the generated electrical signal is converted into an image.

The radiographic image conversion method described in L has the advantage that a radiographic image rich in information can be obtained with far fewer exposed line breaks than in the case of conventional radiography. Therefore, this radiation image conversion method has a high utility value especially in direct medical radiography such as X-ray photography for the purpose of medical diagnosis.

The radiation image conversion panel used in the radiation image conversion method described in L is composed of a support and a light layer provided on one side of the support. The surface of the layer opposite the support (the surface facing away from the support) is generally provided with a transparent protection 11 to protect the phosphor layer from chemical alteration or physical impact. protected from.

The phosphor layer consists of a stimulable phosphor and a binder that supports the stimulable phosphor in a dispersed state. When irradiated with electromagnetic waves selected from light and infrared rays, it emits light (
It has the property of exhibiting (photostimulated luminescence). Therefore,
The radiation transmitted through the subject or emitted from the subject is absorbed by the phosphor layer of the radiation image conversion panel in proportion to the amount of radiation, and the radiation image of the subject or subject is displayed on the radiation image conversion panel. It is formed as an image of accumulated energy. This accumulated image can be emitted as stimulated luminescence (fluorescence) by exciting it with electromagnetic waves (excitation light) selected from visible light and infrared rays, and this stimulated luminescence can be read photoelectrically and converted into an electrical signal. This makes it possible to image the accumulation of radiation energy.

The radiation image conversion method is a very advantageous image forming method as mentioned above, but the radiation image conversion panel used in this method also has high sensitivity, similar to the intensifying screen used in conventional radiography. , and image quality (!!'fl sharpness, graininess, etc.) are desired to be excellent.

1. The sharpness of the image in the radiation image information method using stimulable phosphor described above is basically determined by the spread of fluorescence (instantaneous light emission) in the intensifying screen, as in conventional radiography. Rather, it is determined by the spread of the excitation light within the radiation image conversion panel. This is because the radiation energy accumulation images accumulated in the radiation image conversion panel are retrieved in a time-series manner, so that the bright nope emission due to the excitation light irradiated within a certain time is the same as that when the excitation light was irradiated within that time. Although it is recorded as the output from a group of phosphor particles in the panel, the excitation light spreads within the panel due to scattering or reflection, and also excites phosphor particles existing outside the irradiation target phosphor particles Iff. If the irradiation 1
This is because the output from a wider area than the target phosphor particle group will be recorded.

Therefore, in general, the image quality, particularly the sharpness, of a radiation image conversion panel is improved by reducing the thickness of the phosphor layer, but at the same time, the sensitivity tends to decrease. In order to improve the image quality without causing this deterioration, the mixing ratio of the binder and the stimulable phosphor in the phosphor layer is reduced, and the phosphor layer of the panel is made of stimulable phosphor. It is desirable to have a phosphor layer filled with high density.

On the other hand, the radiation image storage panel has sufficient mechanical strength to prevent the support and phosphor layer from easily separating even when subjected to mechanical damage such as impact, dropping, bending, etc. It needs to be strong. In particular, the radiation image storage panel itself hardly changes in quality even when irradiated with radiation or electromagnetic waves ranging from visible light to infrared rays, so it can be used repeatedly over a long period of time. is the imaging of radiation images by radiation irradiation and subsequent electromagnetic wave irradiation,
Furthermore, even if a mechanical shock is applied during handling of the radiation image conversion panel during operations such as erasing residual radiation image information, failures such as separation of the support and the phosphor layer will not occur. is necessary.

However, the binder of the phosphor layer in contact with the support and the bright J
The smaller the mixing ratio (binder/stimulable phosphor) with the stimulable phosphor (binder/stimulable phosphor), the higher the loading of the stimulable phosphor in the phosphor layer, the more the interaction with the support becomes. Adhesion strength with the body layer tends to be low F.

For example, it has been proposed to use cellulose derivatives as a binder for radiation image conversion panels in view of the dispersibility of the photostimulated cellulose 1 phosphor in the binder solution (coating solution). However, the mechanical strength of the 111 panel is insufficient, and the phosphor layer in particular tends to peel off from the support. It has also been proposed to use polyester resin as a binder for the phosphor layer from the viewpoint of flexibility and adhesion to the support.
In this case, an i
It is difficult to obtain nine layers.

Furthermore, when a phosphor layer is provided on a support by a normal coating method using the binder described in 1-1, since these binders have low affinity with the stimulable phosphor, the phosphor layer During the drying process, the binder and stimulable phosphor particles tend to separate relatively easily, and as a result, a relatively large number of phosphor particles aggregate on the support side, while There are relatively fewer phosphor particles on the side where the irradiation and stimulated luminescence readings are carried out, and the so-called binder
Floating J occurs. In such a radiation image storage panel, especially when the phosphor layer is highly filled, the stimulable phosphor particles in the phosphor layer aggregate on the support side, causing the phosphor layer and the support to Sufficient adhesion strength cannot be obtained,
In addition, on the panel surface side, the excitation light tends to spread due to the lifting of the binder, resulting in a problem in that the image quality tends to deteriorate.

An object of the present invention is to provide a radiation image conversion panel that has both the characteristics of being able to provide images with high sharpness and mechanical strength, particularly high adhesion strength of a phosphor layer to a support. It is something.

The above object 1j is a radiation image conversion panel having a support and a phosphor layer made of a binder that contains and supports the stimulable phosphor in a dispersed state, which is provided on the support 1-.・General formulas (I), (II) and (■): (However, R+
, R3 and R5 are each a hydroxide or an alkyl group; R2 is any one of an alkyl group, a cycloalkyl group, an aryl group, a heterocyclic group, and an aralkyl group, and R4 is either itself or an alkyl group. and R2≠R4; and X, y and 2 each represent a molar percentage, 5≦X≦99, l≦y+z
≦95, and x+y+z≧90)
This is achieved by a radiation image storage panel characterized by containing a (meth)acrylic copolymer having repeating units represented by , in a range of 5 to 100% by weight.

Next, the present invention will be explained in detail.

The present invention uses a (meth)acrylic copolymer as a binder for a phosphor layer of a radiation image storage panel.
In a radiation image conversion panel, the sharpness of the obtained image is improved and the mechanical strength of the panel is improved.

That is, the (meth)acrylic copolymer used in the present invention has high affinity with the phosphor particles. Therefore, by including a (meth)acrylic copolymer in the binder of the radiation image storage panel, the binder can be filled with the stimulable phosphor at a high density. In addition, even if the phosphor layer is filled with stimulable phosphor at a high density, the binding agent does not easily lift up, so it is possible to increase the adhesion strength between the phosphor layer and the support. The (meth)acrylic copolymer used in the present invention is flexible and therefore has excellent bending resistance, which can improve the mechanical strength of the panel against hard blows, bending, and the like.

By filling the phosphor layer of the radiation image storage panel with a stimulable phosphor at a high density, it becomes possible to obtain images with high sitting sharpness without significantly lowering the sensitivity of the panel. Furthermore, because lifting of the binder in the phosphor layer is less likely to occur, even if the mixing ratio of binder and stimulable phosphor is the same, the images obtained are sharper than those of conventional radiation image conversion panels. It is possible to significantly improve the degree of

The radiation image conversion panel of the present invention having the preferable characteristics as described above in 1-1 can be manufactured, for example, by the following method.

The phosphor layer is basically a layer consisting of a binder containing and supporting stimulable phosphor particles in a dispersed state.

The binder, which is a characteristic requirement of the present invention, has the above-mentioned general formula (
, l), (n) and (III).

In the above general formulas (I), (I[) and (III), R1, R3 and R5 are each hydrogen or, when an alkyl group, 1 to 4 groups such as methyl, ethyl, propyl, butyl, etc. Preferably, it is an alkyl group having a carbon atom.

R2 is preferably an alkyl group having 1 to 20 carbon atoms such as methyl, ethyl, propyl, butyl, hexyl; 5 to 12 carbon atoms such as cyclopentyl, cyclohexyl
cycloalkyl groups having 7 to 20 carbon atoms; aryl groups such as phenyl; heterocyclic groups such as pyridyl; and aralkyl groups having 7 to 20 carbon atoms such as benzyl, phenylethyl, phenylpropyl, phenylbutyl, naphthylmethyl. It is one of the following.

R4 is hydrogen, or methyl when it is an alkyl group,
If it is an alkyl group having 1 to 6 carbon atoms such as ethyl, propyl, butyl, hexyl.

However, R4 is not the same as R2.

The (meth)acrylic copolymer preferable as a binder for the radiation image storage panel of the present invention is preferable from the viewpoint of affinity with bright J-beam phosphor particles and film hardness when a coating film is formed. 2 is 50≦X≦95.5≦y+z≦
50, and a numerical value in the range of x+y+Z≧95. Also, X, y and 2 are 70≦X≦95, y=o
, 5≦2≦30 and xy+z≧95. It is particularly preferable that x+y+z=100.

When x+y+z is less than 100, it means that the (meth)acrylic copolymer contains other repeating units, and examples of such other repeating units include aliphatic alkylene, styrene, Mention may be made of divalent groups derived from vinyl derivatives and acrylamide.

In addition, the above-mentioned general formulas (I) and (■) used in the present invention
The (meth)acrylic copolymer having a repeating center represented by It can be obtained by carrying out a copolymerization reaction by a known method using as raw materials monomers selected from , methacrylate trile, and, if desired, other monomers that can be copolymerized with these monomers.

The (meth)acrylic copolymer used in the present invention is
It may be crosslinked with a crosslinking agent.

Examples of the crosslinking agent include aliphatic or aromatic polyisocyanates.

In the phosphor layer, the above-mentioned (meth)acrylic copolymer is used in a binder containing 5 to 100% by weight. However, from the viewpoint of the dispersibility of the phosphor particles in the binder solution, the uniformity of coating, and the hardness of the coated film, the binder for the phosphor layer should be 40 to 90% of the above (meth)acrylic copolymer. Preferably, the composition is based on weight percentages and balances of other binder components.

In the present invention, examples of the binder component that is combined with the (meth)acrylic copolymer include polyester, polyurethane, polyisocyanate, cellulose derivative,
Polyalkyl methacrylate.

Examples include synthetic polymeric substances such as cellulose resins, amino resins, melamine resins, and the like. Particularly preferred among such binder components are nitrocellulose, polyalkyl methacrylates, and mixtures of nitrocellulose and polyisocyanates.

As mentioned above, the 117-vector phosphor is a phosphor that exhibits stimulated luminescence when irradiated with radiation and then with excitation light, but from a practical standpoint, excitation in the wavelength range of 400 to 800 nm is preferred. The phosphor is preferably a phosphor that exhibits stimulated luminescence in the wavelength range of 300 to 500 nm when exposed to light. Examples of the stimulable phosphor used in the radiation image conversion panel of the present invention include SrS:Ce, Sm, and SrS:Eu described in US Pat. No. 3,859,527 [11].

Sm, Th02:E r, and La2O2S:E
u, Sm, ZnS described in JP-A-55-12142 Kano Publication
:Cu, Pb, BaO11xA1203 :Eu (however, 0.8≦X≦10), and M”O fist
i O2: A (However, Mll is Mg, Ca, S
r, Zn, Cd, or Ba, and A is Ce, Tb,
Eu, Tm, Pb, T-text, Bi, or Mn, and X
is 0.5≦X≦2.5), as described in JP-A-55-12143 (
B a 1-X-)”+ M gX+ C
a Y) FX: aEu” (where, X is at least one of C0 and Br, X and y are 0 x + y ≦ 0.6, and x y # O-c,
a is to-'≦a≦5×10-2), LnO described in JP-A-55-12144
X: xA (Ln is La, Y, Gd, and Lu
X is at least one of C1 and Br, A is at least one of Ce and Tb, and X is O<x<O, l), JP-A-Sho 55-12145 (B
ax-x, M2+x) FX: yA (However, M2
+ is at least one of Mg, Ca, Sr, Zn, and Cd (7), X is at least one of C1, Br, and ■, A is Eu, Tb, Ce, Tm, Dy, P
at least one of r, Ho, Nd, Yb, and Er, and X is 0≦X≦0.6, and y is 0≦y≦0
．． 2).

etc. can be mentioned.

However, the stimulable phosphor used in this 93 light! The material is not limited to the phosphors described in ±1, but any phosphor that exhibits stimulated luminescence when exposed to radiation and then irradiated with excitation light may be used.

The nine-body layer A1 can be formed on the support, for example, by the following method.

First, the stimulable phosphor and binder described in (1) are added to a suitable solvent and mixed thoroughly to prepare a coating solution in which phosphor particles are uniformly dispersed in the binder solution.

Examples of solvents for preparing the coating solution include lower alcohols such as methanol, ethanol, n-propanol, and n-butamel; chlorine-containing hydrocarbons such as methylene chloride and ethylene chloride; acetone, methyl ethyl ketone, methyl isobutyl ketone, etc. Ketones; esters of lower fatty acids and lower alcohols such as methyl acetate, ethyl acetate, and butyl acetate; ethers such as dioxane, ethylene glycol 7-methyl ether, and ethylene glycol 7-methyl ether; and mixtures thereof. .

The mixing ratio of 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 phosphor, etc., but in general, the mixing ratio of the binder and the stimulable phosphor is :1 to 1:100 (11', :a: Lt
), preferably from 1:8 to 1:50
(i quantity ratio).

Incidentally, the coating liquid has a phosphor content nk in the coating liquid.
A dispersing agent to improve the properties of the phosphor, and U (various additives such as plasticizers) to improve the bonding force between the binder and the phosphor in the phosphor layer after formation. Examples of dispersants used for such purposes include phthalic acid, stearic acid, caproic acid, lipophilic surfactants, etc.And examples of plasticizers include: Phosphate esters such as phosphorus diphenyl, tricresyl phosphate, and diphenyl phosphate; Phthalate esters such as diethyl phthalate and dimethoxyethyl phthalate; Glycolic acid esters such as ethyl phthalyl ethyl glycolate and butyl butyl phthalate; , polyesters of polyethylene glycol and aliphatic dibasic acids, such as polyesters of I-diethylene glycol and adipic acid, and polyesters of diethylene glycol and succinic acid.

The coating solution containing the phosphor and binder prepared as described above is then uniformly applied to the surface of the support to form a coating film of the coating solution.

This coating operation can be carried out using conventional coating means such as a doctor blade, roll coater, knife coater, etc.

The formed coating film is then dried by gradually heating to complete the formation of the phosphor layer on the support. The thickness of the phosphor layer depends on the characteristics of the intended radiation image conversion panel,
Although it varies depending on the type of phosphor, the mixing ratio of the binder and the phosphor, etc., it is usually 20 gm to 1 mm. However, the thickness of this layer is preferably 50 to 500 gm.

Note that the phosphor layer does not necessarily have to be formed by directly applying the coating liquid to the support as described above; for example, it is possible to form the phosphor layer by separately applying the coating liquid onto a sheet such as a glass plate, metal plate, plastic sheet, etc. After the phosphor layer is formed by drying, it may be pressed onto the support, or the support and the phosphor layer may be bonded together using an adhesive.

The support used in the present invention can be arbitrarily selected from various materials used as supports for intensifying screens in conventional radiography.

Examples of such materials include cellulose acetate,
Films of plastic materials such as polyester, polyethylene terephthalate, polyamide, polyimide, triacetate, polycarbonate, aluminum foil,
Examples include metal sheets such as aluminum alloy foil, ordinary paper, baryta paper, resin-coated paper, pigment paper containing pigments such as titanium oxide, and paper sized with polyvinyl alcohol. However,
When considering the characteristics and handling of the 4-wire i conversion panel as an information recording material, a particularly preferred material for the support in the present invention is a plastic film. This plastic film may be kneaded with a light-absorbing substance such as carbon black, or may be kneaded with a light-reflective substance such as di-titanium oxide. The former is a support suitable for a high sharpness type radiation image conversion panel, and the latter is a support suitable for a high sensitivity type radiation image conversion panel.

In known radiation image conversion panels, gelatin is added to the surface of the support on the side where the phosphor layer is provided in order to strengthen the bond between the support and the phosphor layer, or to improve the sensitivity or image quality of the radiation image conversion panel. A polymeric material such as is coated to create a single layer of adhesive properties, or a light-reflecting layer made of a light-reflecting material such as titanium dioxide, or a light-absorbing layer made of a light-absorbing material such as carbon blank is provided. This is also being done. The support used in the present invention can also be provided with these various layers, and their configurations can be arbitrarily selected depending on the purpose, use, etc. of the desired radiation image storage panel.

Furthermore, as described in Japanese Patent Application No. 57-82431 filed by Mizu applicant, in order to improve the sharpness of the obtained image, the surface of the support on the phosphor layer side (the fluorescent layer of the support) If an adhesion-imparting layer, a light-reflecting layer, or a light-absorbing layer is provided on the surface of the body layer (meaning the surface), even if minute irregularities are uniformly formed on the surface. good.

In a typical radiation image conversion panel, a transparent protective film for physically and chemically protecting the phosphor layer is provided on the surface of the phosphor layer on the side opposite to the side in contact with the support. It is preferable that such a transparent protection pattern 1 be provided also for the radiation image conversion panel of unexposed lino.

The transparent protective film can be made of, for example, cellulose d4 such as cellulose acetate or di-cellulose; or a synthetic material such as polymethyl methacrylate, polyvinyl butyral, polyvinyl formal, polycarbonate-1, polyvinyl acetate, or vinyl chloride-vinyl acetate copolymer. It can be formed by coating the surface of the phosphor layer with a solution prepared by dissolving a transparent polymer material such as a polymer material in an appropriate solvent. Alternatively, it can also be formed by a method such as adhering a transparent thin film separately formed from polyethylene terephthalate, polyethylene, vinylidene chloride, polyamide, etc. to the surface of the phosphor layer using a suitable adhesive. The thickness of the transparent protective film thus formed is preferably about 3 to 20 μm.

Next, Examples and Comparative Examples of the present invention will be described.

However, each of these does not limit the present invention. In each of the following, "part" represents "modified part" unless otherwise specified.

[Example 1] Particles of photostimulable divalent europium-activated barium fluoride bromide phosphor (BaFBr:Eu2+) and an acrylic copolymer (Cryscoat P-10180s, manufactured by Dai-11 Ink Kagaku ■; however, x =60.y=30 and z=IO) After adding methyl ethyl ketone to the mixture, stir and mix thoroughly using a propeller mixer to uniformly disperse the phosphor particles and mix the binder and the phosphor. Ratio is 1:25 (weight ratio)
A coating liquid having a viscosity of 25 to 35 PS (25°C) was prepared.

BaFBr: Eu2 + phosphor 500 parts Acrylic copolymer 20 parts Methyl ethyl ketone 110 parts Next, a carbon-incorporated polyethylene terephthalate film (support, thickness: 250 gm) placed horizontally on a glass plate was placed on the second side. The coating liquid was applied uniformly using a doctor blade. After coating, the support on which the coating film was formed was heated to 90' C1 and at a wind speed of 1.
It was heated and dried for 10 minutes at a speed of 0 m/sec.

In this way, a phosphor layer having a layer thickness of about 250 pm was formed on the support l-.

Then, a transparent film of polyethylene terephthalate (thickness: 12 JLm, with a polyester adhesive attached) is placed on top of this phosphor layer with the adhesive layer side facing down to protect the transparency. A film was formed to produce a radiation image storage panel consisting of a support, a phosphor layer and a transparent protective film.

[Example 2] In Example 1, aliphatic polyisocyanate (crosslinking agent; Sumidur N, Sumidur urethane) was added to the coating solution.
A support was obtained by carrying out the same treatment as in Example 1, except that nitrocellulose (binder) and tricresyl phosphate (01 plasticizer) were added to make the coating solution have the following composition. , a radiation image storage panel composed of a phosphor layer and a transparent protective film was manufactured.

1.5 parts BaFBr2 Eu2+ phosphor 500 parts acrylic copolymer 16 parts polyisocyanate 1.0 parts nitrocellulose 2.5 parts tricresyl phosphate
0.5 part methyl ethyl ketone
95 parts [Example 3] In Example 1, aliphatic polyisocyanate (crosslinking agent; Sumidur N, Resident Bayer Urethane ■) was added to the coating solution.
), polymethyl methacrylate (binder, BR-1
07, = made by Hishishi Yon), nitrocellulose (binder)
A support, a phosphor layer, and a transparent protective film were formed by the same treatment as in Example 1 except that tricresyl phosphate (plasticizer) was added and the coating solution had the following composition. A radiation image conversion panel was manufactured using the following methods.

1 color 1 color BaFBr: Eu2+ phosphor 500 parts acrylic copolymer 14 parts polyisocyanate I 1.0 parts polymethyl methacrylate 2.0 parts nitrocellulose
2.5 parts tricresyl phosphate
0.5 part methyl ethyl ketone
95 parts [Comparative Example 1] In Example 1, a linear polyester resin (Vylon #500, manufactured by Toyobo ■) and nitrocellulose were used instead of the acrylic copolymer as the binder, and triylene isocyanate (crosslinked) was added to the coating solution. A support, A radiation image storage panel composed of a phosphor layer and a transparent protective film was manufactured.

BaFBr: Eu2+ phosphor 500 parts Linear polyester resin 17 parts Triylene isocyanate 0.8 parts Nitrocellulose 2.0 parts Tricresyl phosphate
0.2 part n-butanol
5.7 parts methyl ethyl ketone
87 parts [Comparative Example 2] The method of Comparative Example 1 was followed, except that the coating liquid had the following composition and the mixing ratio of the binder and the phosphor was 1:15 (heavy lubricant ratio). A radiation image conversion panel consisting of a support, a phosphor layer, and a transparent protective film was manufactured by performing the same treatment as described above.

Ikuminato" 1 Imonoki BaFBr: Eu"ii photoresist 500 parts Linear polyester resin 28.1 parts I lilylene isocyanate 1.3 parts nitrocellulose 3.1 parts tricresyl phosphate
0.5 part n-butanol
5.7 parts methyl ethyl ketone
75 parts [Comparative Example 3] In Example 1, nitrocellulose was used instead of the acrylic copolymer as the binder, and tricresyl phosphate (plasticizer) and n-butanol (solvent) were added to the coating solution 4J. Except that the liquid had the following composition and the mixing ratio of binder and phosphor was 1:15 (tunpu ratio).
A radiation image storage panel composed of a support, a phosphor layer and a transparent protective film was manufactured by carrying out the same treatment as in Example 1.

Below, '+11'1 Nuri jL night! 1 piece BaFBr:Eu” phosphor 500 parts 2j
・Rocellulose 32 parts Tricresyl phosphate 1.0 parts n-butanol 5.7 parts Methyl ethyl ketone
Each of the radiation image conversion panels manufactured as described in Section 75 was evaluated by the image sharpness test described below and the adhesion strength test of the Tatophoto layer to the support.

(1) Image sharpness test After irradiating the radiation image conversion panel with X-rays with a tube voltage of 80 KVp,
) to excite the phosphor particles, and the stimulated luminescence emitted from the phosphor layer is received by a light receiver (photomultiplier tube with spectral sensitivity S-5) and converted into an electrical signal, which is then converted into an image. The image was reproduced as an image by a reproduction device to obtain an image on a display device. The modulation transfer function (MTF) of the obtained image was measured and expressed as a spatial frequency of 2 cycles/mm.

(2) Adhesion strength test A radiation image storage panel was cut into a test piece having a width of 10 mm, and a cut was made at the interface between the phosphor layer and the support. Then, the adhesion strength of the phosphor layer to the support was measured by pulling apart the support portion of the test piece prepared in this manner and the phosphor layer and protective film portions. The measurement was performed using Tensilon (Bundle 7Y UTM-II- manufactured by Baldwin).
20), the two sections were pulled in the 1+' (l angle force direction (90° peeling)) at a pulling speed of 10 mm/min, so that the phosphor layer was 10 mm! All! l L
The adhesion strength was expressed by the force F (g/cm) acting during the test.

The results obtained for each radiation image conversion panel are
Shown in the table. In Table 1, B/P represents the bead mixing ratio of the binder and the phosphor.

Table 1 B/P vF: Adhesion strength, sharpness (weight ratio) (g/cm) (%) Example 1
1/25 370 342 1/25
460 343 1/25 400
33 Comparative Example 1 1/25 80 312
1/15 250 283 1/15
30 28 From the results summarized in Table 1,
The radiation image conversion panels (Examples 1 to 3) according to the present invention are as follows:
Compared to conventional radiation image conversion panels (Comparative Examples 1 to 3), the adhesion strength between the phosphor layer and the support is excellent even when the phosphor particles are packed in the GT light layer at a high density. , and it is clear that the image sharpness is also significantly superior.

Claims (1)

[Claims] ■. A support and a photoreceptor provided on the support
i!・In a radiation image conversion panel having a phosphor layer made of a binder containing and supporting a light substance in a dispersed state, the binder has the following formulas: (I), (I[) and (I[): (However, ,
R, R, and R5 are each hydrogen or an alkyl group; R2 is any one of an alkyl group, a cycloalkyl group, an aryl group, a multicyclic group, and an aralkyl group, and R4 is one of hydrogen and an alkyl group. and R2 is R4; and X, y and 2
respectively represent the molar white fraction, 5≦X≦99, l≦y
+z≦95, and x+y+z≧90), containing a (meth)acrylic copolymer having a repeating unit represented by 5 to 1% by weight,
A radiation image conversion panel characterized in that: 2゜J 2x of general formulas (I), (n) and (I[),
y and 2 are 50≦X≦95.5≦y+z≦50. )(+y+z≧95, and”
The binder described above binds the (meth)acrylic copolymer to 4
The radiation image conversion panel according to Claim WS1, characterized in that it contains gold orite in a range of 0 to 90% by weight. 3.1- General formulas (L), (II) and (I [I) x, y and 2 are 70≦X≦95, y=o, 5≦Z≦
30 and a numerical value in the range of x+y+z≧95 □. The radiation image conversion panel according to claim 2. 4゜x, y of the above general formulas (I), (n) and (I[)
and Z are )(+y+z=100).The radiation image storage panel according to claim 2, wherein the (meth)acrylic copolymer is crosslinked with a crosslinking agent. The radiation image conversion panel according to claim 1, characterized in that: 6. The radiation image conversion panel according to claim 5, characterized in that the crosslinking agent described in 6. is a polyisocyanate. 7.゜L Exhaustible phosphor is a divalent europium-activated alkaline earth metal fluorohalide phosphor, according to any one of claims 1 to 6. The radiographic image conversion panel described.