JPS61133898A - Radiation shielding material - 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 (Industrial Field of Application) The present invention relates to a radiation ffl shielding material, more specifically, a radiation ffl shielding material suitable for an interior material coated to prevent radiation transmission and exposure in a medical radiation generation room, etc. 6 regarding X shielding material
The shielding material of the present invention is suitable, for example, as a floor tile.

(Conventional technology) Conventionally, various materials have been used as radiation shielding materials.

For example, thin lead plates, lead blocks, and sheets made by mixing lead powder or lead oxide powder with plastic are known. However, once a lead plate becomes wrinkled, it is difficult to flatten it, which hinders repeated use, and lead blocks have the disadvantage that they cannot be adapted to changes in use location or shape.

In addition, recently, regulations have become stricter regarding X-ray room interior materials such as X-ray protective tiles, and conventional products cannot pass the new standards, so countermeasures have been desired.

(Problems to be Solved by the Invention) An object of the present invention is to solve the above-mentioned problems and to provide a shielding material that completely eliminates the danger to radiation irradiation workers.

(Means for solving problem c, σ) The present invention is based on an fj41 layer consisting of a synthetic resin layer containing iron or iron compound powder, and a synthetic resin layer containing lead-like powder on the back side of the fj41 layer. The present invention relates to a radiation shielding material characterized in that a second layer is laminated.

The present invention will be explained below based on the drawings. FIG. 1 is a sectional view of the shielding material of the present invention. (1), (2), and (3) are synthetic resin parts, and the synthetic resins include vinyl chloride homopolymer (PVC), coperimer of vinyl chloride and ethylene or vinyl acetate, ethylene-vinyl acetate copolymer, and acrylic resin. , thermoplastic polyurethane, thermoplastic polyester, etc.

The first layer of the present invention is obtained by adding iron or iron compound powder (hereinafter abbreviated as iron powder, etc.) to the synthetic resin part (1), kneading it, and forming it into a sheet by, for example, the Kaleng method. Iron powder, etc. (4) includes iron powder, iron oxide powder, 7-elite, iron sand, metal W1. The particle size thereof is preferably about 350 μm or less, more preferably about 250 μm or less.

The amount of iron powder etc. added is 10-5 in terms of metallic iron in the first layer.
0% (weight%, the same applies hereinafter), preferably about 20 to 30%
It is. The thickness of the sheet is preferably about 0.3 to 0.7 II1 m.

The second layer of the present invention is produced in the same manner as the first layer except that lead or lead compound powder (hereinafter abbreviated as lead powder, etc.) is used instead of iron powder or the like. Lead powder, etc. (5) includes lead powder, white lead powder, lead oxide, preferably with an aspect ratio of 30 to 150.
S#iJl! Examples include lead fibers with a millimeter of 5 or less.

The amount of lead powder etc. added is approximately 50~ in terms of metallic lead in the 2nd N.
85%, preferably about 60-80%. The particle size of lead powder, etc. and the thickness of the PIS two-layer sheet are 1/! The same as in is preferred.

As a more preferred embodiment of the present invention, a third layer consisting of a synthetic resin layer to which iron powder (4°) and lead powder (5°) are added can be laminated on the lower surface of 11<2M. The third layer is the first
This layer can be created in the same manner as the second layer. The amount of iron powder, etc. added is preferably about 5 to 15%, and the amount of lead powder, etc. added is about 20 to 5%.
0% is preferred. The thickness of the third layer of the synthetic resin portion (3) is preferably about 0.3 to 11IIIn.

The radiation shielding material of the present invention can be produced by laminating the first layer, the second layer, and optionally the third layer in this order, and then hot-pressing the layer with a press, laminator, Ohma machine, or the like. Further, a PVC layer having a thickness of 1 ml or less, preferably 0.2 to 0.5 mm, may be provided as a decorative material layer on the first layer.

Furthermore, a backing material (6) can be provided on the second layer or the lower surface of fifJ37Fl. PVC as lining material
Examples include layers, felt, nonwoven fabric, cheesecloth, and the like.

(Effects of the Invention) The radiation shielding material of the present invention has an iron-containing layer on the surface and a barb-containing layer on the back, so it does not cause any deformation and can fully satisfy the stricter JIS Z4818 standard. It has this excellent effect.

Even more surprisingly, the necessary radiation #l shielding properties can be obtained by directly adhering the shielding material of the present invention to a mortar base, whereas conventional methods had no choice but to temporarily adhere a lead sheet, aluminum plate, etc. to the base. Compared to conventional methods, construction is easier and construction costs can be significantly reduced.

(Example) The present invention will be explained below with reference to Examples.

Example 1 Compositions A, B, and C having the formulations (parts by weight) shown in Table 1 were each heated at 160°C, mixed and mixed to give zero
．． 51 thick sheet, A is the first layer, B is the second WI,
C as the third layer, laminated in this order using a laminator, and after providing a PVC backing material on the bottom surface of the third layer,
After removing distortion using a hot air oven (C), this was punched out to obtain a radiation shielding floor tile with a thickness of 2 m.

Example 2 1111 layers of A in Example 1 and 12 layers of Ble:ff were laminated in this order using a laminator to obtain a thickness of 11111 layers.
11 radiation shielding materials were obtained.

The obtained floor tiles and shielding materials were tested in accordance with the method of JiS Z4508 at a voltage of 80 kV, using aluminum plates, lead plates, and concrete plates as standard plates to determine the scattering xi of X-rays reflected from the surface, and the weight percentage. and the scattering ratio was measured. The results are shown in Table 2.

Experiment number 1 is 15fim thick aluminum plate, 2 is 5n
+m thick lead plate, 3 is 110fflI11 thick concrete plate. Experiment numbers 4 to 6 are the radiation #l shielding floor tiles of Example 1, and experiment numbers 7 to 9 are samples in which the radiation shielding material of Example 2 is laminated to the standard plate of Experiment Numbers 1 to 3 above.

As an interior material for an X-ray room, the scattering ratio must be 0.4 or less according to JIS 74818. The scattering ratio of the present invention was 0°4 or less, and a satisfactory X-ray shielding effect was obtained.

Also, even when using a concrete board as the base, JIS is sufficient.
It was able to pass the Z4818 standard.

Chapter 1 Table Table 2

[Brief explanation of drawings]

Figure PpJ1 is a cross-sectional view of the radiation shielding material of the present invention, (1)
~(3) is the synthetic sugar part, (4) and (4゛) are iron or iron compound powder, (5) and (5') are lead or lead compound powder, and (6) is the lining material. . (Above) Patent applicant: Toyo Linoleum Co., Ltd. Kawase
Kazuo

Claims (4)

[Claims] (1) A first layer consisting of a synthetic resin layer containing iron or iron compound powder, and a second layer consisting of a synthetic resin layer containing lead or lead compound powder on the back side of the first layer. radiation shielding material. (2) The radiation according to claim 1, wherein a third layer consisting of a synthetic resin layer containing iron or iron compound powder and lead or lead compound powder is laminated on the back side of the second layer. Shielding material. (3) The radiation shielding material according to claim 1 or 2, wherein the content of iron or iron compound in the first layer is about 10 to 50% by weight in terms of metallic iron. (4) The radiation shielding material according to claim 1 or 2, wherein the content of lead or a lead compound in the second layer is about 50 to 85% by weight in terms of metallic lead.