Radiation shielding material and production method therefor

Patent metadata

Field	Value
Publication number	US-10128010-B2
Application number	US-201515536578-A
Country	US
Kind code	B2
Filing date	Dec 14, 2015
Priority date	Dec 15, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

[Object] To provide a radiation shielding material that includes a resin composition obtained by filling a matrix formed of resin with a radiation-absorbing substance and is capable of obtaining a structure in which transparency is significantly improved as compared with the conventional radiation shielding material while having a radiation shielding effect similar to that of the conventional radiation shielding material. [Solving Means] A radiation shielding material includes: a resin composition containing a proportion of 20 to 80 vol % of fluoride powder containing barium as a constituent element. The fluoride powder is favorably barium fluoride or lithium barium fluoride, the resin favorably has a refractive index (n) of 1.4 to 1.6, and particularly, a difference between a refractive index of the resin and a refractive index of the fluoride powder is favorably within ±0.05.

First claim

The invention claimed is:

1. A radiation shielding material, comprising:
a resin composition containing a proportion of 20 to 80 vol % of fluoride powder containing barium as a constituent element, wherein
a difference between a refractive index of resin constituting the resin composition and a refractive index of the fluoride powder is within ±0.05.

2. The radiation shielding material according to claim 1 , wherein
the fluoride powder is barium fluoride or lithium barium fluoride.

3. The radiation shielding material according to claim 1 , wherein
resin constituting the resin composition has a refractive index of 1.4 to 1.6.

4. The radiation shielding material according to claim 1 , wherein
an average particle diameter of the fluoride powder is 10 to 500 μm.

5. A radiation shielding material formed of a molded body, the molded body including a filling layer formed of a resin composition obtained by filling metal fluoride powder in resin, wherein
a density of the metal fluoride powder is not less than 4.6 g/cm 3 ,
a difference between a refractive index of the resin and a refractive index of the metal fluoride powder is within ±0.07, and
a part or whole of the filling layer in a thickness direction includes a layer in which a filling rate of the metal fluoride powder is not less than 40 vol %.

6. The radiation shielding material according to claim 5 , wherein
metal fluoride constituting the metal fluoride powder is formed of simple metal fluoride or a solid solution of a plurality of metal fluorides.

7. The radiation shielding material according to claim 5 , wherein
a particle shape of the metal fluoride powder is a spherical shape.

8. The radiation shielding material according to claim 5 , wherein
the refractive index of the resin is not less than 1.4 and not more than 1.6.

9. The radiation shielding material according to claim 8 , wherein
the resin is epoxy resin, vinyl chloride resin, acrylic resin, cycloolefin resin, or silicone resin.

10. The radiation shielding material according to claim 5 , wherein
a total light transmittance of the molded body is not less than 65%.

11. The radiation shielding material according to claim 5 , wherein
a haze of the molded body is not more than 40%.

12. The radiation shielding material according to claim 5 , wherein
a lead equivalent of the molded body is not less than 1.0 mmPb.

13. The radiation shielding material according to claim 5 , wherein
the molded body is a lens part of goggles or spectacles.

14. The radiation shielding material according to claim 5 , wherein
the molded body is a pipe for transporting liquid containing a radioactive substance.

15. The radiation shielding material according to claim 5 , wherein
the molded body is a radiation shielding sheet.

16. The radiation shielding material according to claim 5 , wherein
the molded body is a syringe for radioactive substance-containing liquid.

17. A production method for a radiation shielding material, comprising:
preparing resin and metal fluoride powder, a difference between a refractive index of the resin and a refractive index of the metal fluoride powder being within +0.07, a density of the metal fluoride powder being not less than 4.6 g/cm 3 ;
preparing a resin composition including the resin and the metal fluoride powder; and
molding the resin composition, at least a part of the resin composition including a layer in which a filling rate of the metal fluoride powder being not less than 40 vol %.

18. The production method according to claim 17 , wherein
the preparing the metal fluoride powder includes adjusting a refractive index of the metal fluoride powder by making solid solution of the metal fluorides.

19. The production method according to claim 17 , wherein
the preparing the resin includes adjusting a refractive index of the resin by a mixture of resins having different refractive indices.

Assignees

• Tokuyama Corp

Inventors

• Miyazaki Kojiro

Classifications

• G21F5/018

  Syringe shields or holders (syringe shielding for applying radioactive material to the body {A61M5/1785}) · CPC title

• G21F1/103 Primary

  Dispersions in organic carriers · CPC title

• G21F3/02

  Clothing · CPC title

• G21F3/00

  Shielding characterised by its physical form, e.g. granules, or shape of the material · CPC title

• G21F1/10

  Organic substances; Dispersions in organic carriers · CPC title