JPS5932900A - Radiation image conversion sheet - 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 is a radiation image falsification sheet (
(hereinafter referred to as "fluorescent sheet"). 91 In detail, it relates to a fluorescent sheet that does not easily cause radiographic (ψ) rays, and has a film made of an organic film with a JFk constant haze rate (≦Morriness value). line, (X111I
i! When it is irradiated with radiation such as β rays, the J energy is accumulated inside the phosphor, and later the phosphor is irradiated with 1f rays and infrared electromagnetic waves], and the row width is heated. When you do this, it emits fluorescent light. 2. This kind of semen accumulation firefly [1]
Firefly consisting of body) Y monolayer is paper, plus boots, metal? W plate etc. is I') ノ, C6 support □ body "plate shape, drano,
A) that takes the form of a light bulb covers the unknown fine print (hereinafter, these will be collectively referred to as ``fluorescence sea 1'') and transmits radiation through the body. A radiation latent image of the subject is stored and stored, and later the phosphor layer of the phosphor sheet is irradiated with viewing light, infrared rays, and other electromagnetic waves, and the body 11v. By heating the sheet and making it emit light, and detecting the emitted fluorescence, it is accumulated and recorded within the fluorescent sheet. 6) 1: Radiation division to see radiological images: A search method is being put into practical use (for example, in the United States/NVrtT US as
No. 5a527, 11'-'+Open IJ (35!11.24
(See No. 29 Kasani). ″ □ By the way, one layer of the phosphor layer is on the surface of the phosphor layer of the phosphor sheet.
Protects against rain and cracks, and protects against moisture and chemicals.
Conventionally, organic fluorocarbons have been used for the purpose of improving physical and chemical properties such as preventing

In many cases, the transparent protective film is crossed. However, these; fi fit(), irno, ri(+,
1. It was used as a general film (・The world was first used as a fluorescent sheet.
/-Copy range like a laser tip-(CoherenC
When a good light source of y) is used as an IjjrJ light source, a certain amount of light will be generated during the manufacturing process of the crushing membrane (i.e., the mausoleum film). , RUWASU, KA (101 to previous μm culm reduction), ``Radiographic image with streaks and partial membrane thickness, and strongyles - E4, 20.7□7゜W ,-1,I-7ikJetヮ1.
. 1,9. B. It is extremely uneconomical in industry to sort out uniform organic films for removal. There is a problem and I would like to see an improvement. The present invention has been made in view of the above-mentioned situation. - Combined with excitation light with good beam coherency 1゛1
JLj L, far″゛1″′combined 1 is also radiation “””
The purpose is to obtain a phosphorescent sheet in which image '4' ・:: is less likely to occur. As a result of the samurai's divine research on the retention of fluorescent sheets, the inventors of wood discovered that the retention of fluorescent sheets was ``5j'' (the haze rate of the organic film used as a film and the noise of radiographic images). Appearance and 1
There is a correlation between, and has a specific haze rate.
l□15, e1,4,)j! The world of "l" line image noise, 11. Obtained fluorescent sheet
I'll find that I can do it. The fluorescent light of the present invention is combined with a binder and an accumulative substance dispersed in the binder. /The phosphor layer and the combined intestinal membrane are laminated on the supporting body in this Ili.
7), the above protection @ armpit has a haze rate of 5
It is characterized by consisting of ~40% organic finosino. To produce the fluorescent sheet of the present invention, (1) Mix the stimulable phosphor and the binder in a suitable solvent, peel it off from the substrate, and adhere it onto a support. After forming a phosphor layer on the surface of the phosphor layer, either an organic film is attached to the surface of the phosphor layer for 1 inch, or a coating solution made of a resin that becomes an organic film after drying is applied to the phosphor layer. Apply to layer surface 1
7) Dry to form a pupil-retaining film made of a film on the surface of the phosphor layer. The protective film of the fluorescent sheet of the present invention has ASTM D-103
Haze rate is 5 to 40% when measured by the method described in
Polyester films such as polyethylene terephthalate, polymethacrylate films, nitrocellulose films, cellulose acetate films, etc.
1° film is used, but it has low elongation properties and is 17. Oyo. 1lIi, ltsu2,1
□K, 7,. :shi, □2. . Ka, I'p'
r, jK□49. It is best to use polyesterdelf ilms such as care, 7kets, 7'z v-mouths, etc. Also, please stop J[1, please! (Iy, press 1 limit 4, but,
I used one from 5 to 25 Jim. ! Yes,
Hold Is j'>% haze failure 1 (・rao [rui 1 (
Shishi Firno's 1m Kl, the difference in degree of polymerization, the difference in the degree of polymerization, the angle included, 1 + 51. '[
□Other than that, the same organic film was used (the nth of the thickness was different), and the surface of the organic film was uniformly matted. (1) It is possible to attenuate (1) C:Mj by changing the ftl1 and 11 thickness of the organic film or by applying appropriate surface treatment. A poppy protective film can be provided from an organic film having a haze ratio of It is not recognized that - as the haze rate of the organic film used increases, the radiation of the phosphor sheet increases as the organic film is used. The noise in one shot is reduced, but the sensitivity gradually decreases, and when the haze rate is higher than 40 inches, the feeling becomes worse.
From a practical point of view, since II is approximately 0 or less than the conventional one, 4011! t is less than or equal to i
It is preferable to use an organic film with a haze rate of 8 to 25% for zl' and lr. The various materials used in the fluorescent sheet of the present invention, other than the retention film, are the same as those used in conventional fluorescent sheets. 1. As a storage fluorophore, i, Sr8: Cs, Eu, BrB:
Bu, Sm, 'ZnS: Cu, Pb, (Z
n, Cd)S :hl+t,X ((j,l,X
halogen), LnOX:,,A (LH and Ln is La
At least one of 5Y, Gd and Lu, X is CI
and Br in □ at least 1′], and A is Ce and at least one in
X: Ln (where M is A4g, Ca, 5rSZn and C ((), after receiving one irradiation, excitation '1- or A phosphor that emits fluorescence when the soil is heated is used. As the binder resin, nitrified cotton, agglomerated vinyl-vinyl acetate copolymer, polyvinyl butyral, etc. are used. Also, as a support material For use with plastic films such as Naruross Tatefinome, polyrecarbonate films, paper, glass plates, aluminum, etc.N4
1 and 1 are applied, and if necessary, a light absorbing layer and a reflective layer are provided on the surface of these supports. - The fluorescent sheet of the present invention produced as described above is
After storing and recording the radiation image of the subject, the radiation image is reproduced by excitation with excitation light with good coherency, such as a laser beam. Although the sensitivity is reduced by '1'', the radiographic image noise can be significantly reduced.Next, the present invention will be explained with reference to Examples.Example 1 BaFBr: gu2+ fluorophore (Storage fluorophore) 8
A phosphor coating solution was prepared by mixing 1 part of heavy In and 1 part of tonitrocellulose (binder) with a solvent. Next, apply this coating solution horizontally by 1 to 1 cm.
black polyethylene terephthalate film (support)
Apply it evenly on top with a knife coater 1. Dry for about 30 minutes
A phosphor layer with a thickness of 0 μm was formed. Next, on the surface of this phosphor layer, a polyethylene alkaline/phthalate film (manufactured by Toshisha Co., Ltd.,
Fluorescent sheet) A was prepared by adhering a film made of Lumirror type P-30). Apart from this, as a comparative example 1, the film thickness was 12μ as a Hosai membrane.
A polyethylene terephthalate film (manufactured by Toshisha Co., Ltd., Lumirrtine S-30) having a haze rate of 2.5 inches was prepared in the same manner as in Fluorescent Sheet 1-A except that R was used. Created. Fluorescent sheet) A, and Fluorescent sheet R, He −
A radiographic image of the same object obtained using Ne laser light as excitation light (a fluorescent sheet was excited with He-Np laser light (I7j The obtained radiographic image f#7 information was reproduced on photographic film) When compared with Fluorescent Sheet) 8', the sensitivity of Fluorescent Sheet) A is approximately 95% of that of Fluorescent Sheet 1-R.
However, by correcting the gaps in image reproduction on photographic film 1 and the difference in sensitivity between the respective phosphor sheets, the corresponding parts of both reproduced images had the same degree of blackening. (,;',) When compared in this way, a large amount of pure noise was clearly visible to the naked eye on the radiation image obtained with the fluorescent sheet R, whereas the fluorescent sheet R) On the 2 & cross-line image obtained by A, the noise of the Ar rays that appears on the image obtained with the fluorescent light 1-H is removed.
rt I couldn't get enough of it. Example 2 A polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., Polyester Film Noise E 1512) having a film thickness of 12 μm and a haze ratio of 22 was used as a haze protective film. -y-・Excluding fireflies of Example 1)゛(, sheet h
and 4N- to prepare a fluorescent sheet B. If'-Nev-the-)" B and the fluorescent light produced for comparison.
'l; is used as excitation light (・radiation-pure image of the same subject obtained (each fire Y4 sea) k When excited with He-Ne laser light, 1 and 2) radiographic image f8" When the information was reproduced on photographic film and compared with the results, it was found that there were about 90 hits each for firefly, )1-C113, black Jj, fluorescent sheet R, but the image reproduction on photographic film was At this time, correct the □sensitivity□ difference of each fluorescent sheet (2,
The corresponding part of both reproduced images is pVJ-. Kurohihire, f, (7;, ryoi 1-2, 7, :,: When I did 5, the radiant group 1 portrait was reduced by 1↓1 by the fluorescent sheet R.)
While a large number of linear noises were clearly visible to the naked eye, there were no visible noises that appeared on the radiographic images obtained with the optical sheet □B and on the images obtained with the fluorescent sheet □R. : No linear noise was observed at all. □, 1・ 1′j・ ■ Su,,,11. 1. ・：

Claims (1)

[Claims] (11: A phosphor layer consisting of a binder and stimulable phosphor particles dispersed in the binder and a security film are laminated in this order on a support.) In the radiation image conversion sheet, the film has a -\Iz ratio (haze value) of 5 to 40.
% of organic fill, [conversion sea]. σ) The radiographic image conversion sheet according to the range 1. (3) The peritoneal membrane J! is 5 to 25 zlrn). or the radiation image converting sheet according to item 2. (4) The scope of claim 1, item 2, or 3 of the patent "i) 9, wherein the film is a polyethylene terephthalate film. Radiant pure conversion sheet described in section.