KR20150122105A - Radioactivity protective sheet and method for manufacturing radioactivity protective sheet - Google Patents

Abstract

The purpose of the present invention is to provide a radioactivity protection sheet, which can protect a body or an article from radioactivity in an easy manner and can block radioactivity in daily life, and a method for manufacturing the same. The radioactivity protection sheet of the present invention includes radiation blocking layers containing chlorosulfonated polyethylene and radioactive-ray-blocking particles. The radioactive-ray-blocking particle includes tungsten or tungsten compounds (a), and/or barium or a barium compound (b). The radioactivity protection sheet is a laminate having a plurality of the radiation blocking layers. Moreover, the radioactivity protection sheet includes the radiation blocking layers which include radiation blocking layers including tungsten or tungsten compounds (a) and radiation blocking layers including barium or a barium compound.

Description

TECHNICAL FIELD [0001] The present invention relates to a radiation protection sheet and a radiation protection sheet,

The present invention relates to a radiation protection sheet and a method of manufacturing the same.

Examples of the clothes considering the adverse effect on the human body by the radioactive material include: A. a radiation protective clothing for preventing the radioactive material such as radioactive dust from being deposited on the human body, and a radiation protective clothing for shielding the radiation emitted by the radioactive material.

In the above radioactive protective clothing (A), even if the radioactive dust floats in the air, the radioactive dust is deposited on the clothes without being deposited on the human body, and then the radioactive dust adhered to the clothes is washed away, It is possible to prevent the dust from adversely affecting the human body. However, this radiation protective clothing does not shield the radiation itself, but even if the radiation protective clothing is worn, the wearer is exposed to radiation and is exposed.

On the other hand, in the above radiation protective clothing (B), for example, in the case of performing work in a nuclear power plant, it is used to prevent exposure of workers. As this radiation protective clothing, a layer containing lead is generally used to shield radiation. However, since lead is concerned about health damage, it is necessary to pay close attention when disposing of the radiation protection clothing after the content period.

It is also proposed that the radiation protective clothing (B) has a polymer layer in which a polymer such as polyurethane is mixed with a radiopaque material (JP-A-2008-538136). In this publication, barium sulfate, tungsten and the like are exemplified in addition to lead as a radiopaque material. However, since the radiation protective clothing described in this publication is made to have a high radiation shielding effect, it is necessary to include a large amount of the radiation-impermeable material, and as a result, it becomes very heavy and also becomes a high liquid.

Nowadays, people who consider protecting the body from radiation exposure by radiation are increasing even in a place other than a special place such as a nuclear power plant, that is, a place of everyday life. However, even if the radiation protective clothing (A) is worn, the radiation is exposed to radiation. In addition, since the radiation protective clothing (B) is very heavy and expensive, it is not realistic to wear it in daily life.

Japanese Patent Publication No. 2008-538136

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a radiation protection sheet capable of easily and accurately shielding radiation and being easily usable in daily life, and a method of manufacturing the radiation protection sheet.

In order to solve the above problems,

Chlorosulfonated polyethylene,

Radiation shielding particles

And a radiation shielding layer containing the radiation shielding layer,

Wherein the radiation shielding particles

(a) a tungsten or tungsten compound, and / or

(b) a barium or barium compound

Is a radiation protection sheet.

Since the radiation protection sheet has the radiation shielding layer containing the chlorosulfonated polyethylene and the radiation shielding particles, the radiation shielding layer can shield the radiation shielding layer. Particularly, since the radiation shielding sheet mainly contains chlorosulfonated polyethylene as the binder of the radiation shielding layer, radiation can be shielded not only by the radiation shielding particles but also by the binder. For this reason, when the radiation protection sheet is used, for example, when a radiation protection clothing is produced, the radiation can be shielded more accurately than the conventional radiation protection clothes. In addition, the radiation protection sheet contains chlorosulfonated polyethylene and is therefore excellent in weather resistance, ozone resistance, chemical resistance and the like. For this reason, the radiation protection sheet can be suitably used for an article intended for long-term outdoor use. In addition, the chlorosulfonated polyethylene has excellent color stability and exhibits rubber-like elasticity at room temperature. Therefore, the chlorosulfonated polyethylene is easy to be processed into a fashionable product such as a radiation protective clothing, and the feeling of wearing when this fashioned product is worn is also good. In addition, since the radiation shielding sheet uses (a) tungsten or a tungsten compound and / or (b) barium or barium compound as radiation shielding particles and does not use lead, the radioactive shielding sheet Disposal methods and environmental pollution prevention measures are not troublesome.

It is preferable that the radiation shielding sheet contains barium sulfate as the radiation shielding particles. By employing barium sulfate as the radiation shielding particles as described above, it is possible to accurately shield the radiation by the radiation shielding particles which are relatively easy to obtain.

The radiation protection sheet may have a plurality of the radiation shielding layers. As a result, for example, there is a limitation in the coating amount of the coating machine used when the radiation protection sheet is produced, so that even when a desired film thickness can not be obtained with a single coating, A desired film thickness can be achieved.

The radiation protection sheet may be provided with a radiation shielding layer containing (a) a radiation shielding layer containing tungsten or a tungsten compound, and (b) a radiation shielding layer containing a barium or barium compound. Thus, the color tone of the outer surface can be selected while maintaining the radiation shielding effect of the radiation protection sheet. Specifically, the (a) tungsten or tungsten compound is mainly black, and (b) the barium or barium compound is mainly white or colorless, so that the color tone of the outer surface can be appropriately selected. For example, in the case where the radiation protection sheet is used for an article in which contamination is not conspicuous, (a) a radiation shielding layer containing tungsten or a tungsten compound is arranged on the outer surface, and on the contrary, (B) a radiation shielding layer containing barium or barium compounds may be arranged on the outer surface. (B) a radiation shielding layer containing barium or a barium compound is arranged on the outer surface of the radiation protection sheet; (b) a red or blue coloring matter other than the barium or barium compound is added; A picture may be printed on the outer surface side of the layer so as to give the radiation protection sheet the decorative effect. As described above, since the radiation protection sheet can be provided with designability, it is possible to distinguish each radiation protection sheet by setting a difference in appearance. That is, for example, it is possible to distinguish between the content of the radiation shielding particles and the size of the radiation protection sheet (the size of the coating formed by the radiation protection sheet) by color, for example.

(B) a radiation shielding layer comprising (a) an average particle size of the tungsten or tungsten compound, and (c) an average particle size of the tungsten or tungsten compound, (B) the average particle diameter of the barium or barium compound to the diameter may be 0.01 or more and 0.1 or less. As a result, barium or barium compounds (b) having an average particle diameter smaller than that of (a) tungsten or tungsten compound having a large average particle diameter are introduced into a gap, and the barium or barium compound The density can be increased, and the radiation shielding effect of the radiation protection sheet can be enhanced.

The radiation protection sheet preferably has a ratio of (b) barium or barium compound (a) to (a) tungsten or tungsten compound of 5 mass% or more and 50 mass% or less. Thus, (b) the barium or barium compound can sufficiently enter into the gap between the (a) tungsten or the tungsten compound, and the density of the radiation shielding particles in the radiation protection sheet can be increased. As a result, the radiation shielding effect of the radiation protection sheet can be further enhanced.

It is preferable that the proportion of the above radiation shielding particles in the radiation shielding layer is 30 mass% or more and 85 mass% or less. As a result, a radiation shielding effect to such an extent as to effectively protect the wearer from radiation can be imparted to the radiation protection sheet, and the production can be relatively easily performed.

It is preferable that the areal density of the radiation shielding particles in the radiation shielding layer is 0.1 g / cm ² or more and 1 g / cm ² or less. This also makes it possible to suitably apply the radiation shielding effect to the radiation protection sheet to such an extent that the wearer or the like can be effectively protected from the radiation.

The radiation protection sheet may further comprise a base layer. Thus, the strength of the radiation protection sheet can be improved.

The radiation protection sheet may further include an antifouling layer on the outermost layer. Thus, it is possible to make it difficult for the contaminants such as radioactive substances to adhere to the outer surface of the radiation protection sheet. As a result, the wearer and the like can be protected more effectively from the radioactivity, and the radioactive material is hardly attached to the radioactive protective sheet and the attached radioactive material can be easily removed.

The antifouling layer may be a resin layer whose main component is an olefin resin. The olefin-based resin layer has a high surface tension and can exhibit excellent antifouling properties.

According to another aspect of the present invention,

(A) a tungsten or tungsten compound and / or (b) a barium or barium compound are dispersed as a radiation shielding particle in a binder containing chlorosulfonated polyethylene as a main component and a material for preparing a radiation shielding layer forming material A preparation process,

A sheet forming step of forming the radiation shielding layer forming material on the sheet body

Of the radiation shielding sheet.

According to the above production method, a radiation protection sheet comprising a chlorosulfonated polyethylene and a radiation shielding layer containing the radiation shielding particles is obtained. The radiation protection sheet can protect the wearer easily from radiation and radiation in daily life as described above.

"Radiation" means the ability to emit radiation when an unstable nucleus is converted to a stable nucleus. "Radiation" means electromagnetic waves such as X-rays and γ-rays emitted from the radioactivity (radioactive material), and particle beams such as α-rays, β-rays and neutron rays. The " average particle diameter " is a volume average particle diameter, and is a value measured at 23 DEG C by dynamic light scattering measurement. Specifically, a submicron particle diameter analyzer (" NICOMPMODEL370 " manufactured by NOZAKI SANGYO KABUSHIKI KAISHA) was used as a measuring device, and as a sample to be measured, a radiation having a radiation shielding particle content of 0.1 to 2.0% by mass was dispersed in tetrahydrofuran A shielding particle dispersion was used. The term " plane density " means the ratio (mass) of the radiation shielding particles per unit area (1 cm ² ) in the planar direction of the radiation protection sheet.

INDUSTRIAL APPLICABILITY As described above, the present invention can provide a radiation protection sheet and a method of manufacturing the radiation protection sheet that can shield radiation easily and accurately, and can be easily used in everyday life.

1 is a schematic cross-sectional view showing a radiation protection sheet according to an embodiment of the present invention.
Fig. 2 is a schematic sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Fig. 1; Fig.
Fig. 3 is a schematic cross-sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Figs. 1 and 2. Fig.
Fig. 4 is a schematic sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Figs. 1 to 3. Fig.
Fig. 5 is a schematic sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Figs. 1 to 4. Fig.
Fig. 6 is a schematic sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Figs. 1 to 5. Fig.
7 is a schematic cross-sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Figs. 1 to 6. Fig.
8 is a schematic cross-sectional view showing a radiation protection sheet according to a different embodiment from the radiation protection sheet of Figs. 1 to 7. Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings appropriately.

[First Embodiment]

≪ Radiation Protection Sheet (1) >

The radiation protection sheet 1 of Fig. 1 is composed of a sheet-shaped flexible radiation shielding layer containing chlorosulfonated polyethylene and radiation shielding particles. The radiation shielding particles include (a) tungsten or tungsten compounds and (b) barium or barium compounds.

The chlorosulfonated polyethylene has crystallinity inhibited by introducing chlorine into crystalline polyethylene and imparted with rubber elasticity. Since chlorosulfonated polyethylene does not contain a double bond in its main chain, it is excellent in weather resistance, ozone resistance, heat resistance, flame retardancy and the like, and also has a radiation shielding effect because it contains chlorine as a halogen. Since the radiation protection sheet 1 has rubber elasticity by containing such chlorosulfonated polyethylene as a binder, it can be easily deformed and processed depending on the shape of the object to be coated. For example, as the decorative material such as a coat, It can be suitably used. The radiation protection sheet (1) is excellent in weather resistance, ozone resistance, heat resistance, and the like by having the above chlorosulfonated polyethylene, so that it can be suitably used for long-term use in outdoor use and for articles used for outdoor work .

The chlorosulfonated polyethylene can be produced, for example, by chlorinating and chlorosulfonating a polyethylene dissolved in a solvent by reacting chlorine and sulfurous acid gas using a catalyst. Examples of the polyethylene as the raw material include high-density polyethylene and low-density polyethylene. When high-density polyethylene is used as the raw material polyethylene, chlorosulfonated polyethylene having high mechanical strength and excellent workability is obtained. When low-density polyethylene containing long chain branches is used in the polyethylene, the solution viscosity is low when dissolved in a solvent Chlorosulfonated polyethylene excellent in coatability can be obtained. As the chlorosulfonated polyethylene, trade name "TOSO-CSM" part number "TS-320" available from TOSOH CORPORATION may be used.

Among the above-mentioned (a) tungsten or tungsten compounds, the tungsten compound is not particularly limited as long as it is a compound containing tungsten. Examples of the tungsten compound include carbides (WC, W ₂ C), oxides (WO, WO ₂ , Borides, or complex compounds with other metals such as tungsten alloys. As the (a) tungsten or tungsten compound, tungsten and its carbide, which are easily available and relatively inexpensive, are preferable. As tungsten, trade name " High purity W powder ", manufactured by Nippon Tungsten Co., Ltd., may be used.

The (a) tungsten or tungsten compound is preferably a fine powder. The upper limit of the average particle diameter of the (a) tungsten or tungsten compound is preferably 10 占 퐉, more preferably 7 占 퐉, and further preferably 5 占 퐉. On the other hand, the lower limit of the average particle diameter is preferably 0.5 占 퐉, more preferably 1 占 퐉, and further preferably 2 占 퐉. When the average particle diameter of the (a) tungsten or tungsten compound is larger than the upper limit value, the (a) tungsten or tungsten compound may fall off from the radiation protection sheet, and (a) the average particle diameter of the tungsten or tungsten compound Is lower than the lower limit, there is a possibility that (a) tungsten or tungsten compound is not uniformly dispersed in the radiation shielding layer.

Among the barium compounds or barium compounds (b), barium compounds are particularly preferably used from the viewpoint of availability and the like, but other compounds containing barium can be used, and examples thereof include barium chloride, Barium, barium titanate, and the like.

The barium or barium compound (b) is preferably a fine powder. The upper limit of the average particle diameter of the barium or barium compound (b) is preferably 2.3 占 퐉, more preferably 1.8 占 퐉, and further preferably 1.5 占 퐉. On the other hand, the lower limit of the average particle diameter is preferably 0.3 占 퐉, more preferably 0.8 占 퐉, and further preferably 1 占 퐉. If the average particle diameter of the barium or barium compound (b) is larger than the upper limit value, (b) the barium or barium compound may not be able to fill the gaps between (a) tungsten or tungsten compounds closely, On the other hand, if the average particle diameter of the barium or barium compound (b) is smaller than the lower limit value described above, it may be difficult to handle (b) the barium or barium compound at the time of production.

The barium or barium compound (b) preferably has a smaller average particle diameter than the (a) tungsten or tungsten compound. The ratio of the average particle diameter of the (b) barium or barium compound to the average particle diameter of the (a) tungsten or tungsten compound is preferably 0.01 or more and 0.1 or less, more preferably 0.03 or more and 0.08 or less, More preferable. By setting the average particle diameter of the (b) barium or barium compound to (a) the average particle diameter of the tungsten or tungsten compound within the above range, particles (a) Small (b) barium or barium compounds can enter effectively. As a result, the density of the radiation shielding particles in the radiation shielding layer can be increased and the radiation shielding effect of the radiation protection sheet 1 can be enhanced.

The upper limit of the ratio of (b) barium or barium compound to (a) tungsten or tungsten compound is preferably 50% by mass, more preferably 43% by mass, still more preferably 34% by mass. On the other hand, the lower limit of the ratio of (a) barium or barium compound to (a) tungsten or tungsten compound is preferably 5 mass%, more preferably 8 mass%, and even more preferably 10 mass%. (a) the ratio of barium or barium compound (b) to tungsten or tungsten compound is higher than the upper limit, (a) the ratio of barium or barium compound to excess gaps between tungsten or tungsten compounds is excessive (B) the effect of adding the barium or barium compound may be weakened, and the coating liquid containing both of them may become liable to be in a petrified state, which may result in difficulty in coating. Further, There is a fear that flexibility may be deteriorated. On the other hand, if (a) the ratio of barium or barium compound (b) to (a) tungsten or tungsten compound is lower than the lower limit value, (a) the gap between tungsten or tungsten compound (B) the barium or barium compound can not sufficiently fill the gaps between (a) tungsten or tungsten compounds.

The radiation protection sheet 1 may contain a substance having radiation shielding effect in addition to the above (a) tungsten or tungsten compound and (b) barium or barium compound. Examples of such a material include materials containing an element having an atomic number of 30 or more, and examples thereof include zinc, yttrium, strontium, zirconium, hafnium, niobium, molybdenum, tantalum, tin, lead, And the like. Of these, tin, molybdenum, niobium, tantalum, zirconium, and compounds thereof are preferable from the standpoint of availability.

The upper limit of the proportion of the above radiation shielding particles in the radiation shielding layer 2 is preferably 85% by mass, more preferably 80% by mass, still more preferably 70% by mass. On the other hand, the lower limit of the proportion of the above radiation shielding particles in the radiation shielding layer 2 is preferably 30 mass%, more preferably 35 mass%, and still more preferably 40 mass%. If the ratio of the radiation shielding particles in the radiation shielding layer 2 is larger than the upper limit value, the proportion of the chlorosulfonated polyethylene serving as a binder is relatively decreased, so that the strength of the radiation shielding layer 2 may be lowered There is a possibility that it is difficult to apply the coating liquid containing the radiation shielding particles and the flexibility of the radiation protection sheet 1 may be deteriorated. On the other hand, if the ratio of the radiation shielding particles in the radiation shielding layer 2 is smaller than the lower limit value, the radiation shielding effect of the radiation shielding layer 2 is lowered and the body can not be effectively protected from radiation There is a concern.

The upper limit of the flat density of the radiation shielding particles in the radiation shielding layer ² is preferably 1 g / cm ² , more preferably 0.8 g / cm ² , and even more preferably 0.6 g / cm ² . On the other hand, the lower limit of the flat density of the radiation shielding particles in the radiation shielding layer ² is preferably 0.1 g / cm ² , more preferably 0.3 g / cm ² , and even more preferably 0.4 g / cm ² . If the density of the radiation shielding particles in the radiation shielding layer 2 is larger than the upper limit value, the radiation protection sheet 1 may become excessively heavy. On the other hand, in the radiation shielding layer 2, If the density of the shielding particles is smaller than the above lower limit value, the radiation shielding effect of the radiation shielding layer 2 is lowered, and the body may not be protected effectively from the radiation.

The upper limit of the thickness of the radiation shielding layer 2 is preferably 5 mm, more preferably 3 mm. On the other hand, the lower limit of the thickness is preferably 0.2 mm, more preferably 0.5 mm. If the thickness of the radiation shielding layer 2 is larger than the upper limit value, the radiation protection sheet 1 may become excessively thick, which may make it difficult to deform and modify the shape of the radiation shielding layer 2, 2 is less than the lower limit value, sufficient radiation protection effect may not be obtained and the strength of the radiation protection sheet 1 may be insufficient.

The radiation protection sheet 1 may have an antifouling layer 3 on the outermost layer. As described above, since the radiation protection sheet 1 has the outermost layer 3 on its outermost layer, it is possible to make it difficult for the radioactive substance to adhere to the outer surface of the radiation protection sheet 1. As a result, it is possible to more effectively protect the wearer from the radioactivity, and the radioactive substance is hardly adhered to the radioactive protective sheet and the attached radioactive substance can be easily removed. As the antifouling layer, a resin layer mainly composed of an olefin resin can be suitably employed. The olefin-based resin layer has a high surface tension and can exhibit excellent antifouling properties. As the antifouling layer 3, for example, a film containing a photocatalyst material, a film obtained by performing a hydrophilic surface treatment or an antistatic film may be employed.

The coating film containing the photocatalyst material can decompose contaminants such as fungi and bacteria attached to the outer surface of the radiation protection sheet 1 by ultraviolet rays from the outside to keep the outer surface of the radiation protection sheet 1 clean have. As a result, it is possible to make it difficult for the radioactive material to adhere to the outer surface of the radiation protection sheet 1.

As the photocatalyst material, for example, TiO ₂ , ZnO, SrTiO, CdS, GaP, InP, GaAs, BaTiO ₃ , K ₂ NbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , NiO, Cu ₂ O, SiC, SiO ₂ , MoS ₂ , InPb, RuO ₂ , and CeO ₂ . Among these, titanium oxide (TiO _2), peroxide titanium (per oxo titanate), zinc oxide (ZnO), tin oxide (SnO _2), strontium titanate (SrTiO _3), tungsten (WO _3), bismuth oxide (Bi ₂ O oxide ₃ ) and iron oxide (Fe ₂ O ₃ ) are preferable. The particle size of the photocatalytic material is preferably small because it has excellent photocatalytic activity, and specifically, the average particle diameter is preferably 50 nm or less, more preferably 20 nm or less.

The blending amount of the photocatalytic material in the coating containing the photocatalyst material is preferably as large as possible because a high photocatalytic activity can be obtained, and specifically, it is preferably 10% by mass or more and 70% by mass or less. If the compounding amount of the photocatalytic substance is less than 10% by mass, the photocatalytic activity may become insufficient. On the other hand, when the compounding amount of the photocatalytic substance exceeds 70% by mass, the photocatalytic activity becomes high, but the adhesion with the adjacent radiation shielding layer There is a fear of insufficiency and an insufficient surface abrasion strength of the antifouling layer resulting in a decrease in outdoor durability.

It is preferable that the photocatalytic substance is used after being supported on the inorganic porous fine particles. Thereby, the photocatalytic material can be uniformly dispersed in the antifouling layer. Examples of such inorganic porous fine particles include silica, synthetic zeolite, titanium zeolite, zirconium phosphate, calcium phosphate, calcium zinc phosphate, hydrotalcite, hydroxyepatite, silica alumina, calcium silicate, magnesium aluminosilicate, And the like. The average particle diameter of the inorganic porous fine particles is preferably not less than 0.01 mu m and not more than 10 mu m, more preferably not less than 0.05 mu m and not more than 5 mu m. In order to carry the photocatalytic material on the inorganic porous fine particles, it is preferable to carry out the surface treatment applying the sol-gel thin film production process using the metal alcohol latex containing the photocatalytic substance.

The thickness of the coating containing the photocatalyst material is preferably 0.1 m or more and 10 m or less. If the thickness is less than 0.1 m, the antifouling property may not be sufficiently obtained. On the other hand, when the thickness exceeds 10 m, the bending property of the antifouling layer is lowered, and cracks tend to occur easily.

In addition, since the outer surface of the antifouling layer is hydrophilic, the coating film subjected to the hydrophilic surface treatment can reduce the surface tension of the water-repellent sheet 1 when the surface of the radiation-protection sheet 1 has water droplets. As a result, water droplets flow down as water films, so that even if adhering contaminants such as radioactive substances adhere, they are washed away by rainfall or the like, and the outer surface of the radiation protection sheet 1 can be kept clean. Specific examples of the hydrophilic surface treatment include a method of applying a hydrophilic material such as silica or a titania based compound.

In addition, the film subjected to the antistatic treatment can make it difficult to generate static electricity on the outer surface of the radiation protection sheet 1. As a result, dust and dust in the air are hardly attracted to the outer surface of the antifouling layer due to static electricity, so that the radioactive material is less likely to adhere to the outer surface of the radiation protection sheet 1. Specific examples of the antistatic treatment include conductive metal oxide fine particles such as tin oxide, antimony oxide, antimony oxide-zinc oxide composite, antimony oxide-tin oxide composite (ATO), and indium oxide-tin oxide composite (ITO) And a method of applying the coating material containing the antistatic agent on the outermost surface of the radiation protection sheet 1.

In addition, various kinds of additives may be added to the radiation-protective sheet 1 insofar as the object of the present invention is not impaired. Examples of such various additives include dyes, pigments, inorganic reinforcing agents, plasticizers, processing aids, ultraviolet absorbers, light stabilizers, lubricants, waxes, nucleating agents, plasticizers, mold release agents, hydrolysis inhibitors, anti-blocking agents, antistatic agents, Antistatic agents, ion trap agents, flame retardants, flame retarding agents, inorganic fillers, and organic fillers.

The upper limit of the art aeration amount of radiation protective sheet 1, for example, 60L / m ² / sec and more preferably 50L / m ² / sec. On the other hand, as the lower limit of the aeration amount 20L / m ² / sec and more preferably 30L / m ² / sec. If the amount of air permeation of the radiation protection sheet 1 is larger than the upper limit value, the air permeability of the radiation protection sheet 1 is excessively high and there is a possibility that a fine radioactive dust or the like is passed and the wearer is exposed. On the other hand, If the airflow amount of the air bag 1 is smaller than the lower limit value, sufficient air permeability can not be obtained, and there is a possibility that heat or steam emitted by the wearer can not be sufficiently emitted to the outside.

The moisture permeability of such radiation protective sheet (1) includes, for example 100g / m ² / 24hr or less is preferable, and, 50g / m ² / 24hr, and more preferably not more than, 10g / m ² / 24hr or less is more preferred, and non moisture-permeable Is particularly preferable. When the moisture permeability of the radiation protection sheet 1 is larger than the upper limit value, radioactive moisture permeates and sufficient radiation shielding effect can not be obtained, which may cause the wearer or the like to be exposed. Further, it is preferable that at least the art radiation protective sheet (1) As the lower limit of the moisture permeability 1g / m ² / 24hr of. Here, this moisture permeability is a measured value measured at a temperature of 40 DEG C and a relative humidity of 90% in accordance with JIS ZO208 Cup method.

<Radiation protective clothing>

The radiation protection sheet 1 can be suitably used as a raw material for the radiation protective clothing by cutting and sewing by a known method. Since this radiation protective clothing can prevent the radioactive material from adhering to the wearer or the like, it is possible to effectively protect the wearer from radiation. In addition, since the radiation protection cloth prepared using the radiation protection sheet 1 is provided with the radiation shielding layer 2, radiation in daily life can be shielded, and the wearer can be protected simply from exposure.

<Advantages>

Since the radiation protection sheet 1 having the above structure is provided with the radiation shielding layer 2 containing the chlorosulfonated polyethylene and the radiation shielding particles, the radiation shielding layer 2 can prevent the wearer, It can effectively protect against radiation. In addition, since the radiation protection sheet 1 contains chlorosulfonated polyethylene, it can be suitably used for an article which is excellent in weather resistance, ozone resistance, chemical resistance and the like and which is intended for long-term outdoor use. The chlorosulfonated polyethylene has excellent color stability and exhibits rubber-like elasticity at room temperature. Therefore, the chlorosulfonated polyethylene is easy to be processed into embroidery products such as a coat, a hat, gloves, and the like, and the wearing feeling when worn is good. In addition, the radiation protection sheet 1 is provided with an antifouling layer on the outermost layer, so that the antifouling property of the radiation protection sheet 1 can be improved, thereby more effectively protecting the wearer from radiation, It is possible to effectively prevent the secondary contamination such as the radioactive material attached to the radiation protection sheet 1 being unintentionally moved to another place.

&Lt; Method for producing radiation-sensitive protective sheet (1)

The production method of the radiation protection sheet (1) comprises a material preparing step of preparing a material for forming a radiation shielding layer in which radiation shielding particles are dispersed in a chlorosulfonated polyethylene as a binder using a solvent; And a step of forming an antifouling layer on one side of the sheet body obtained in the sheet forming step.

Examples of the material preparation process include a method in which chlorosulfonated polyethylene, the radiation shielding particles and a solvent are charged into a stirrer and stirred to prepare a material for forming a radiation shielding layer.

The solvent is not particularly limited, and examples thereof include water and an organic solvent. It is also possible to use a latex in which water is used as a solvent and chlorosulfonated polyethylene is dispersed.

As the sheet forming step, a method of forming a sheet body by coating the radiation shielding layer forming material obtained in the material preparing step on a process paper to be continuously flowed can be mentioned. As a means for applying the radiation shielding layer forming material to the process paper, well-known methods can be used. For example, a slit coat method, a roll coat method, a blade coat method, an air knife coat method, a flow coat method, a gravure coat method, A spray method or a bar coating method may be used. In addition to the above, known methods such as solution casting (solution casting), melt extrusion, calendering, compression molding, T-die molding and inflation can be employed. Alternatively, for example, there is a method of dropping the radiation shielding layer forming material from a charger onto a process paper, and vibrating the process paper onto which the radiation shielding layer forming material is dropped to form the radiation shielding layer forming material into a uniform sheet shape have. Among them, it is preferable to use a roll coating method which can be applied even if the radiation shielding layer forming material has a high viscosity, and the coating width can be easily changed. The sheet forming step includes a step of drying the applied radiation shielding layer forming material, and the drying step may be a known drying method such as natural drying or hot air drying.

Examples of the antifouling layer forming step include a method in which a photocatalytic material supported on inorganic porous fine particles is contained and dispersed in a suitable binder and is coated on one side of the sheet body obtained in the sheet forming step . As a method for coating the photocatalyst material dispersed in the binder on the sheet member, for example, the coating method used in the sheet forming step can be used.

[Second Embodiment]

&Lt; Radiation protection sheet (11) >

Next, the radiation-protection sheet 11 according to the second embodiment of the present invention will be described below with reference to Fig.

The radiation protection sheet 11 of Fig. 2 comprises a radiation shielding layer 12 comprising chlorosulfonated polyethylene and (a) a tungsten or tungsten compound, (b) a chlorosulfonated polyethylene, and (b) Layer 13 as shown in Fig. The radiation protection sheet 11 is a laminate in which the radiation shielding layer 12 and the radiation shielding layer 13 are laminated. The radiation protection sheet 11 is composed of only this laminate.

The upper limit of the average thickness of the radiation shielding layer 12 is preferably 1 mm, more preferably 700 탆, and further preferably 500 탆. On the other hand, the lower limit of the average thickness of the radiation shielding layer 12 is preferably 10 占 퐉, more preferably 100 占 퐉, and further preferably 300 占 퐉. If the average thickness of the radiation shielding layer 12 is larger than the upper limit value, the radiation protection sheet 11 becomes heavy and thick, which may lower the handling property. On the other hand, if the average thickness of the radiation shielding layer 12 is smaller than the lower limit value, it may be difficult to form a uniform radiation shielding layer 12 in the manufacturing process.

The average thickness of the radiation shielding layer 13 is the same as the average thickness of the radiation shielding layer 12.

The kinds and average particle diameters of the (a) tungsten or tungsten compound contained in the radiation shielding layer 12 and the (b) barium or barium compound contained in the radiation shielding layer 13 are the same as in the first embodiment (A) a tungsten or tungsten compound and (b) a barium or barium compound, respectively. The ratio of the radiation shielding particles in the radiation shielding layer 12 and the radiation shielding layer 13 and the planar density (the sum of the radiation shielding particles contained in the both layers 12 and 13 in the unit area) Is the same as the radiation shielding layer 2 of the first embodiment.

<Advantages>

The radiation protection sheet 11 is formed by laminating the radiation shielding layer 12 and the radiation shielding layer 13 so that the radiation protection sheet 11 can be irradiated from the radiation to the wearer And the like. Since the (a) tungsten or tungsten compound mainly has a black color and the (b) barium or barium compound is mainly white or colorless, the radiation protection sheet 11 is colored on one side and the other side So that the color tone of the outer surface of the radiation protection sheet 11 can be appropriately selected. Specifically, in the case where the radiation protection sheet 11 is used for an article in which contamination is not conspicuous, the radiation shielding layer 12 is arranged on the outer surface, and conversely, when the radiation protection sheet 11 is used for a product The radiation shielding layer 13 may be arranged on the outer surface. The radiation shielding layer 13 may be arranged on the outer surface of the radiation protection sheet 11 and then a red or blue pigment may be added to the barium or barium compound to form the radiation shielding layer 13. Alternatively, Or a picture may be printed on the radiation protection sheet 11 to give the radiation protection sheet 11 designability. As described above, since the radiation protection sheet can be provided with designability, it is possible to distinguish each radiation protection sheet by setting a difference in appearance. That is, it is possible to distinguish between the content of the radiation shielding particles and the size of the radiation protection sheet (the size of the coating formed by the radiation protection sheet) depending on the color of the outer surface.

&Lt; Method of Manufacturing Radiation Protection Sheet 11 >

The method for producing the radiation protection sheet 11 is not particularly limited. For example, a radiation shielding layer forming material, which is a material of the radiation shielding layer 12, and a radiation shielding layer forming material of the radiation shielding layer 13 And a sheet forming step of forming the radiation shielding layer forming material in a sheet form. The sheet forming step includes a step of forming a radiation shielding layer 12 using one of the radiation shielding layer forming materials obtained in the material preparing step, a step of forming a radiation shielding layer 12 on the radiation shielding layer 12, And a step of laminating the shielding layer 13. Here, the material preparing step and the sheet forming step can be used, for example, in substantially the same manner as the material preparing step and sheet forming step used in the first embodiment described above.

As the sheet forming process, for example, a radiation shielding layer 12 is first formed on a process paper, and a radiation shielding layer forming material serving as a material of the radiation shielding layer 13 is formed on the surface of the radiation shielding layer 12 A method of laminating the radiation shielding layer 13, and the like. In contrast to this, a radiation shielding layer 13 is formed on the process paper, and a radiation shielding layer forming material, which becomes the material of the radiation shielding layer 12, is coated on the surface of the radiation shielding layer 13, (12) may be laminated. In addition to this method, it is also possible to form the radiation shielding layer 12 and the radiation shielding layer 13 separately and then heat-bond them, or to laminate them together with an adhesive .

[Third embodiment]

&Lt; Radiation protection sheet (21) >

Next, the radiation protection sheet 21 according to the third embodiment of the present invention will be described below while referring to Fig.

The radiation protection sheet 21 of Fig. 3 has a base layer 22 on which a radiation shielding layer is laminated, specifically a base layer 22, a radiation shielding layer 13 and a radiation shielding layer 12 in this order Respectively. More specifically, the radiation shielding layer 12 and the base layer 22 are laminated so as to sandwich the radiation shielding layer 13 so as to be the outermost layer of the radiation protection sheet 21, respectively.

The base layer 22 is laminated on one surface of the radiation protection sheet 21 to improve the strength of the radiation protection sheet 21 and is composed of a fabric or a knitted fabric. The fiber constituting the base layer 22 is not particularly limited and examples thereof include polyester fibers, acetate fibers, polyamide fibers, aramid fibers, carbon fibers, rayon fibers, acrylic fibers, polyurethane fibers, Terephthalamide fiber, high-density polyethylene fiber, cotton, hemp or wool, glass fiber, carbon fiber and the like. Among these, cotton, polyester fiber, polyparaphenylene terephthalamide fiber and high-density polyethylene fiber are preferable, and cotton and polyester fiber are more preferable. These fibers may be subjected to brushed treatment.

The thickness of the base layer 22 is not particularly limited and may be, for example, 1 mm or less, preferably 0.1 mm or more and 1 mm or less, and more preferably 0.2 mm or more and 0.5 mm or less. If the thickness of the base layer 22 is less than the lower limit value, there is a fear that the durability of the radiation protection sheet 21 is lowered. On the other hand, if the thickness of the base layer 22 is larger than the upper limit value, (21) becomes heavy and thick, and the handleability may be deteriorated. The thickness of the base layer 22 is an average value of the results measured at five arbitrary locations within a 2 cm radius circle using a trade name &quot; Dial Sikness Gauge DS-1211 &quot; (manufactured by Niigata Seiki Seisakusho) .

The radiation shielding layer (a) 12 and the radiation shielding layer (b) 13 in the radiation protection sheet 21 are the same as the radiation shielding layer (a) 12 and the radiation shielding layer The radiation shielding layer (b) 13 may have the same structure as the radiation shielding layer (b) 13.

<Advantages>

Since the radiation protection sheet 21 further comprises the base layer 22 on one side of the radiation protection sheet 11 in the second embodiment, the strength of the radiation protection sheet 21 And durability can be improved. In the case where the radiation protection sheet 21 is used as a material for a dressing such as a radioactive protective clothing, the base layer 22 is arranged on the side of the wearer in contact with the wearer, have.

&Lt; Method of Manufacturing Radiation Protection Sheet 21 >

The method for producing the radiation protection sheet 21 is not particularly limited. For example, a radiation shielding layer forming material, which is a material of the radiation shielding layer 12, and a radiation shielding layer forming material of the radiation shielding layer 13 And a sheet forming step of forming the radiation shielding layer forming material in a sheet form. The sheet forming step includes a step of laminating the radiation shielding layer 13 on the base material layer 22 using one of the radiation shielding layer forming materials obtained in the material preparing step and the step of laminating the radiation shielding layer 12 to the other radiation shielding layer And a step of laminating the radiation shielding layer 13 made of the layer forming material. Here, the material preparing step may be substantially the same as the material preparing step used in the first embodiment described above, for example. The step of laminating the radiation shielding layer 12 on the radiation shielding layer 13 may be the same as the method of the second embodiment described above, for example.

The radiation shielding layer 13 may be formed in a sheet shape and the radiation shielding layer 13 may be formed on the base layer 22, And the like. In this case, the radiation shielding layer 13 can be laminated on the base layer 22 by so-called transfer. Specifically, as in the first embodiment described above, the radiation shielding layer forming material is coated on the process paper, the base layer 22 is superimposed on the radiation shielding layer forming material in the semi-cured state, So that the radiation shielding layer 13 can be laminated on the base layer 22. The laminating step is not limited to the above-described method, and a method of thermally bonding the formed base layer 22, the radiation shielding layer 12 and the radiation shielding layer 13, a method of laminating and bonding them through an adhesive May be employed. When the base layer 22 is hard to infiltrate with the radiation shielding layer forming material, a method of directly coating the radiation shielding layer forming material on the base layer 22 without using the above-mentioned process paper It is also possible to adopt it.

[Other Embodiments]

The present invention is not limited to the above-described embodiments, but can be carried out by various modifications and improvements other than those described above.

The radiation shielding layer 12 and the radiation shielding layer 13 are stacked one by one in the radiation shielding sheet 11 in the second embodiment. However, as shown in Fig. 4, the radiation shielding layer 11 and the radiation shielding layer 13 are sandwiched The radiation shielding layer 12 may be formed in a three-layer structure (radiation protection sheet 31) laminated on both sides of the radiation shielding layer 13 in order to receive the radiation shielding layer 13 12) and the radiation shielding layer 13 may be alternately stacked, and each of them may have a four-layer structure (radiation protection sheet 41). 6, the radiation protection sheet 51 is made of a radiation shielding layer 2 so as to sandwich the radiation shielding layer 2 having (a) tungsten or tungsten compound and (b) barium or barium compound as radiation shielding particles, Layer structure in which the layer 12 is laminated on both sides of the radiation shielding layer 2.

In the third embodiment, the radiation protection sheet 21 is laminated so that the base layer 22 is the outermost surface of the radiation protection sheet 21, but the base layer 22 is formed as shown in Fig. 7 The radiation shielding layer 12 and the radiation shielding layer 13 may be laminated so as to be sandwiched between the radiation shielding layer 12 and the radiation shielding layer 13 and may be arranged inside the radiation shielding sheet 61 The radiation shielding layer 12, the radiation shielding layer 13, the base layer 22, the radiation shielding layer 13 and the radiation shielding layer 12 may be laminated in this order as shown in Fig. (71).

The base layer 22 may be made of other materials, for example, a rubber sheet, a synthetic resin sheet, a nonwoven fabric, or the like. The base layer 22 may be laminated in the middle part of the radiation prevention layer in addition to being laminated as in the third embodiment.

The radiation protection sheet may be used in addition to the radiation protective clothing, such as raincoats, hats, gloves, boots, and aprons. It can also be suitably used as a sheet of an outdoor article such as an umbrella, a tent, a winter coat, or a waterproof sheet, for example.

[Experimental Example 1]

A radiation shielding layer forming material (coating liquid) was prepared in which tungsten was used as the radiation shielding particles and the radiation shielding particles were dispersed in chlorosulfonated polyethylene as a binder using a solvent. Further, toluene was used as a solvent, and 4 mass% of the total mass of the radiation shielding particles and the binder was added.

The content of the radiation shielding particles (the content of the radiation shielding particles in the radiation shielding layer) with respect to the total mass of the binder and the radiation shielding particles with respect to the above preparation was changed. As a result of the experiment, it has been found that a coating liquid capable of being coated suitably is obtained when the content is 85% by mass or less.

[Experimental Example 2]

A radiation shielding layer-forming material (coating liquid) was prepared in which tungsten and barium sulfate were used as radiation shielding particles, and the radiation shielding particles were dispersed in chlorosulfonated polyethylene as a binder using a solvent. Further, toluene was used as a solvent, and 4 mass% of the total mass of the radiation shielding particles and the binder was added. The content of the radiation shielding particles (the content of the radiation shielding particles in the radiation shielding layer) relative to the total mass of the binder and the radiation shielding particles at the time of preparation was 80 mass%.

As to the above preparation, experiments were conducted by changing the ratio of tungsten to barium sulfate (ratio of barium sulfate to tungsten) as shown in Table 1 below. As a result of the experiment, it was found that 50% by mass or less is preferable and 43% or less is more preferable when the ratio of barium sulfate to tungsten exceeds 60% by mass (two stages from the top of Table 1) . Further, it was found that when no more than 34% by mass (after the fourth stage from the top of Table 1), the petrification state does not occur and is better

INDUSTRIAL APPLICABILITY As described above, the radiation protection sheet of the present invention can shield radiation accurately and simply, and can be easily used in everyday life.

One… Radiation protection sheet 2 ... Radiation shielding layer
3 ... Five layers of stratum ... Radiation protection sheet
12 ... The first radiation shielding layer 13 ... The second radiation shielding layer
21 ... Radioactive Protection Sheet 22 ... The substrate layer
31 ... Radiation protection sheet 41 ... Radiation protection sheet
51 ... Radioactive Protection Sheet 61 ... Radiation protection sheet
71 ... Radiation protection sheet

Claims (4)

As a radiation protection sheet,
One layer is laminated so that one layer and the other layer are in contact with each other by coating the forming material of the other layer on one layer, and one layer is exposed on one surface, and the other layer is exposed on the other surface 1 radiation shielding layer and a second radiation shielding layer,
Wherein the first radiation shielding layer and the second radiation shielding layer comprise a binder containing 50 parts by mass or more of chlorosulfonated polyethylene with respect to 100 parts by mass of the binder composition and the radiation shielding particles dispersed in the binder,
Wherein the polyethylene as the raw material of the chlorosulfonated polyethylene is high-density polyethylene,
Wherein the radiation shielding particles of the first radiation shielding layer are tungsten or tungsten compounds having an average particle diameter of 0.5 탆 or more and 10 탆 or less and the radiation shielding particles of the second radiation shielding layer have a mean particle diameter of 0.3 탆 or more and 2.3 탆 or less, Barium compound,
Wherein the content of the radiation shielding particles in each of the first radiation shielding layer and the second radiation shielding layer is 30 mass% or more and 85 mass%
Wherein the first radiation shielding layer and the second radiation shielding layer have an average thickness of 300 탆 or more and 500 탆 or less, respectively. The radiation protection sheet according to claim 1, wherein the radiation shielding particles comprise barium sulfate. The radiation protection sheet according to claim 1, wherein the total area density of the radiation shielding particles in the first radiation shielding layer and the second radiation shielding layer is 0.1 g / cm ² or more and 1 g / cm ² or less. A method for producing a radiation protection sheet,
(A) a tungsten or tungsten compound having an average particle diameter of not less than 0.5 μm and not more than 10 μm, or (b) an average particle diameter of not less than 50 μm and not more than 10 μm, as the radiation shielding particles, to a binder containing 50 parts by mass or more of chlorosulfonated polyethylene per 100 parts by mass of the binder composition A material preparing step of dispersing a barium or barium compound having a diameter of 0.3 mu m or more and 2.3 mu m or less using a solvent to prepare a plurality of radiation shielding layer forming materials,
A sheet forming step of forming the radiation shielding layer forming material on the sheet body
To have,
The polyethylene used as the raw material of the chlorosulfonated polyethylene used in the material preparation process is high-density polyethylene,
In the sheet forming step,
(a) a first radiation shielding layer wherein the radiation shielding particles are tungsten or a tungsten compound;
(b) after forming one of the layers of the second radiation shielding layer in which the radiation shielding particles are a barium or barium compound, by coating the forming material of the other layer on the one layer, Layered structure of the first radiation shielding layer and the second radiation shielding layer, one of the layers being exposed on one surface and the other layer being exposed on the other surface, Lt; / RTI &gt;
Wherein a content of the radiation shielding particles in each of the first radiation shielding layer and the second radiation shielding layer is 30 mass% or more and 85 mass% or less, and the average thickness of the first radiation shielding layer and the second radiation shielding layer is 300 μm or more Wherein the thickness of the radiation protection sheet is 500 mu m or less.

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