JP2014224328A - Radiation shielding flexible container bag, and radiation shielding bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation shielding woven fabric having high strength and elongation and capable of reducing the leakage quantity of radiation of a radioactive substance covered therewith to the outside, a radiation shielding flexible container bag and a radiation shielding cover including the same, and a radiation shielding bag.SOLUTION: The radiation shielding woven fabric is formed by weaving a tape yarn that has a strength of 3.0 cN/dt or greater and is formed by using a raw material for kneading including 20-90 wt.% of thermoplastic synthetic resin and 10-80 wt.% of barium sulfate. The radiation shielding flexible container bag, the radiation shielding cover and the radiation shielding bag are made by using the woven fabric as a raw material. Thus, the strength is high, and the leakage quantity of radiation of a covered radioactive substance to the outside was able to be reduced.

Description

  The present invention relates to a radiation shielding fabric containing barium sulfate which is a kind of radiation shielding raw material, a radiation shielding flexible container bag and a radiation shielding cover, and a radiation shielding bag produced using the radiation shielding fabric.

With the accident at TEPCO's Fukushima Daiichi Nuclear Power Station on March 11, 2011, a wide range of soils, mainly in Fukushima Prefecture, are contaminated with radioactive materials. The area of soil contamination is large, and the Ministry of Agriculture, Forestry and Fisheries is working on the development of decontamination technology for the soil that is the basis of food production. As part of this, in Fukushima Prefecture, taking into account the ground (paddy fields, fields) and the degree of contamination, topsoil (filler) is scraped from soil with a radioactive cesium concentration of 5000 Bq / kg or more.
Specifically, the topsoil is scraped off by heavy machinery (yumbo), filled into a flexible container bag, transported to a predetermined temporary storage location, and stored until moving to an intermediate storage facility installed in the future. . In the temporary storage method, a flexible container bag filled with contaminated soil is covered with a water shielding sheet or the like.

Utility Model Registration No. 3173174

  By the way, a conventional flexible container bag cuts a plurality of raw fabrics woven with a tape yarn made of thermoplastic resin such as polyethylene and polypropylene into component sheets of a predetermined shape, and then sews adjacent component sheets together. It has a bag shape and does not have a radiation shielding function. Therefore, a large amount of radiation from the contaminated soil leaks outward from the flexible container bag, which increases the level of radioactive contamination of workers engaged in long-term work not only at the site of topsoil cutting but also at the storage location. Had occurred.

  Therefore, as a result of diligent research, the inventor has formed a raw material for kneading of 20 to 90% by weight of a thermoplastic synthetic resin and 10 to 80% by weight of barium sulfate as a raw material from which a component sheet of a flexible container bag is cut. Using a radiation-shielding fabric woven from slits, heat-stretched tape yarns, a lightweight, flexible, radiation-shielding flexible container bag (similar to a radiation shielding cover) is obtained that is light and flexible and not easily torn even when piercing sharp objects. The inventor found that the problem could be solved and completed the present invention.

  The present invention provides a radiation shielding fabric, a radiation shielding flexible container bag and a radiation shielding cover, and a radiation shielding bag using the same, which are high in strength and capable of reducing the amount of external leakage of the radioactive material covered. It is an object.

  The invention according to claim 1 is woven from a tape yarn having a strength of 3.0 cN / dt or more and made using a raw material for kneading of 20 to 90% by weight of a thermoplastic synthetic resin and 10 to 80% by weight of barium sulfate. A radiation shielding fabric.

The raw material for kneading here is a raw material for producing a tape yarn used when weaving a radiation shielding fabric, and specifically includes various thermoplastic synthetic resins and barium sulfate.
Examples of the thermoplastic synthetic resin that is the main raw material for kneading include polypropylene, polyethylene, vinyl chloride, nylon, and polyester. Among these, for example, polypropylene that can ensure the strength, elongation, and durability required for the flexible container bag is preferable. Examples of the properties of the thermoplastic synthetic resin include pellets, granules, and powders.

Barium sulfate is harmless to the human body, and is taken as a contrast agent for digestive organs during, for example, an in-vivo examination using X-rays. Also, the impact on the environment is very small compared to lead.
Precipitating barium sulfate is preferable because of compatibility with the thermoplastic resin.
The property of barium sulfate is arbitrary, for example, powdery or liquid. However, the property of barium sulfate is preferable because it is easy to knead with the main raw material. In that case, the average particle size of the powdered barium sulfate is 10 μm or less, preferably 5 μm or less. If it exceeds 10 μm, it is difficult to uniformly disperse in film formation, and problems such as fish eyes occur. Moreover, the kneading raw material is slit into a predetermined width after film formation, and is heated and stretched to form a tape yarn. However, if the average particle size of the barium sulfate powder exceeds 10 μm, the yarn is easily cut during stretching. Become.

  The amount of barium sulfate added is 10 to 80% by weight based on 100% by weight of the kneading raw material. Correspondingly, the addition amount of the thermoplastic synthetic resin is 20 to 90% by weight on an internal basis with respect to 100% by weight of the kneading raw material. When the amount of barium sulfate added is less than 10% by weight (when the amount of thermoplastic synthetic resin added exceeds 90% by weight), the radiation shielding effect of the radiation shielding fabric cannot be obtained. If the amount of barium sulfate added exceeds 80% by weight (the amount of thermoplastic synthetic resin added is less than 20% by weight), it becomes difficult to form a film as an intermediate product of a tape yarn.

  A raw material for kneading may be mixed with a radiation shielding raw material different from barium sulfate or a substance (additive) having no radiation shielding effect. As different radiation shielding materials, for example, tungsten, bismuth, cerium and the like can be employed. Examples of additives include various additives used for thermoplastic resins, such as antioxidants, light stabilizers, ultraviolet absorbers, neutralizers, lubricants, blocking agents, flame retardants, and pigments.

The tape yarn is generally produced by forming a film from a thermoplastic synthetic resin as a raw material, forming a plurality of slits in the film to form a tape, and then stretching each tape while heating. The tape yarn is made by weaving warps and wefts without any gaps (densely) so that a radiation shielding fabric having a high radiation shielding effect is woven.
When the strength of the tape yarn is 3 cN / dt or less, sufficient strength as a flexible container fabric cannot be obtained.

  The invention according to claim 2 is the radiation shielding fabric according to claim 1, wherein the content of the barium sulfate is 30 to 50% by weight in the kneading raw material.

  When the content of barium sulfate in the kneading raw material is less than 30% by weight, it is difficult to obtain a shielding effect. On the other hand, if it exceeds 50% by weight, uniform dispersion with the thermoplastic resin becomes difficult, film formation and heat stretching are not stable, and it is difficult to obtain a tape yarn having sufficient strength for a radiation shielding fabric.

  According to a third aspect of the present invention, at least one additive selected from a light stabilizer and an ultraviolet absorber is contained in the kneading raw material in an amount of 0.1-2. The radiation shielding fabric according to claim 1 or 2, wherein 0% by weight is added.

  According to the third aspect of the present invention, when the radiation shielding fabric is used as a raw material for the flexible container bag and a raw material (raw fabric) for the radiation shielding cover, these are often used outdoors. High weather resistance is required for exposure to sunlight. As a method for improving the weather resistance, addition of a light stabilizer, an ultraviolet absorber and carbon black can be employed. The added amount is at least one selected from light stabilizers and ultraviolet absorbers, and is 0.1 to 2.0% by weight on the basis of 100% by weight of the raw material for kneading (total in the case of multiple types) % By weight).

  As a hindered amine light stabilizer which is a kind of light stabilizer, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) ) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) .di (tridecyl) -1,2,3,4-butanetetracarboxylate And polycondensates of 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and diethyl succinate. Examples of UV absorbers include 2-ethylhexyl-2-cyano-3,3′-diphenyl acrylate, ethyl-2-cyano-3,3′-diphenyl acrylate, octyl-2-cyano-3,3′-diphenyl acrylate Cyanoacrylate ultraviolet absorbers such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, benzophenone ultraviolet absorbers such as 2-hydroxy-4-octoxybenzophenone, 2- (2′-hydroxy- 5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole and other benzotriazole ultraviolet absorbers, resorcinol monobenzoate, 2,4-di-t-butylphenyl -3′-5′-di-t-butyl-4′- Mud carboxymethyl benzoate-based ultraviolet absorbers such as benzoate and the like.

  The invention according to claim 4 is a radiation shielding flexible container bag having a plurality of component sheets obtained by cutting an original fabric, and sewing the adjacent ones among the plurality of component sheets. The said original fabric is a radiation shielding flexible container bag which consists of a radiation shielding fabric of any one of Claims 1-3.

The use of the radiation shielding flexible container bag is not limited. For example, it is suitable for outdoor work, especially for transportation and storage of contaminated soil (contaminated topsoil) contaminated with radioactive substances.
A flexible container bag is a bag (cloth) made of tape yarn made mainly of polypropylene or the like. The bottom of the bag body or the trunk is sewn to the lower end of the suspension belt. A cylindrical charging part for charging the filler into the body part is sewn on the (upper peripheral part).
As the bag main body, a general one in which a cloth having a dense warp and weft (no gap) is sewn so as to prevent the filler (particularly contaminated soil) from leaking. In addition, you may employ | adopt the bag main body which provided the draining function by making yarn density low.

As the external shape of the bag body, for example, a circular round shape in a plan view, a square shape in a plan view, and the like can be adopted.
The radiation shielding flexible container bag may have an inner bag. As the inner bag, for example, a bag made of synthetic resin such as polyethylene can be employed. The inner bag may be double or triple or more. Further, the radiation shielding fabric of the present invention can be sewn into a cylindrical shape or a bag shape and used as an inner bag.
As an input part, what sewn cloth (radiation shielding textiles) in the shape of a cylinder, or what processed various synthetic resin sheets into the shape of a cylinder, etc. are also employable.
In addition, a drawstring type, in which a fastening string is attached to the upper peripheral edge of the input part so that the input part (saddle part) can be narrowed down, is a general input part. A belt may be used to tie the opening of the charging portion.

As used herein, “raw fabric” refers to a tape yarn having a strength of 3.0 cN / dt or more and made from a raw material for kneading 20 to 90% by weight of a thermoplastic synthetic resin and 10 to 80% by weight of barium sulfate. A cloth (radiation shielding fabric) woven using warp and weft.
The “component sheet” cut from the original fabric here is at least the trunk and the bottom constituting the bag body. In addition, an insertion portion provided around the upper end of the trunk portion, a suspension belt sewn on the trunk portion, a reinforcing cloth (frame) for reinforcing the connection of the suspension belt to the bag body, and the like may be included.
A radiation shielding film such as an aluminum film may be laminated on at least one of the front and back surfaces of the component sheet. Thereby, the radiation shielding effect of the radiation shielding flexible container bag is further enhanced.

  The invention according to claim 5 is a radiation shielding cover made of the radiation shielding fabric according to any one of claims 1 to 3, which is a sheet material that covers a radioactive substance storage body.

The use of the radiation shielding cover is arbitrary. For example, it can be used as a cover for covering a flexible container bag filled with radioactively contaminated soil (radiation shielding).
The shape and size of the radiation shielding cover are arbitrary.

  The invention according to claim 6 is a bag body produced by sewing an outer bag obtained from a raw fabric and an inner bag in which a radiation shielding metal foil layer is laminated on a synthetic resin base film layer, An outer cloth provided in the opening of the bag body through a wire fastener and obtained from the original fabric, and an inner cloth in which the radiation shielding metal foil layer is laminated on the synthetic resin base film layer are sewn. It is a radiation shielding bag provided with the cloth lid produced | generated by wearing, Comprising: The said original fabric is a radiation shielding bag which consists of a radiation shielding textile fabric in any one of Claims 1-3. is there.

The use of the radiation shielding bag is arbitrary. For example, in addition to being used as a general bag filled with a radioactive substance, it may be used as an inner bag of a flexible container bag (including the radiation shielding flexible container bag according to claim 4). When used as an inner bag, the radiation shielding effect of the radiation shielding flexible container bag can be further enhanced, and since it is not exposed to sunlight for a long time, the main raw material (synthetic resin) of tape yarn for weaving the raw fabric There is no need to add a weathering agent, and the strength of the original fabric can be prevented from decreasing due to the addition of the weathering agent.
As the external shape of the bag body, for example, a circular round shape in a plan view and a square shape in a plan view can be adopted.
As the raw fabric for the outer bag and the raw fabric for the outer fabric, for example, the original fabric described in claim 4 can be adopted.

As a material for the synthetic resin base film layer, for example, polyethylene, polypropylene, or the like can be employed. The synthetic resin base film layer for the inner bag and the synthetic resin base film layer for the inner cloth may be the same material or different materials.
As the radiation shielding metal foil layer, for example, an aluminum foil or the like can be employed. The radiation shielding metal foil layer for the inner bag and the composite radiation shielding metal foil layer for the inner fabric may be the same material or different materials.
The number of laminated layers of the synthetic resin base film layer and the radiation shielding metal foil layer is arbitrary. As the number of these layers increases, the strength of the bag body and the cloth lid increases, and the self-supporting property of the radiation shielding bag increases, and the work of holding the opening of the radiation shielding bag during filling of the radioactive substance becomes easier.
As the line fastener (slide fastener), for example, various zippers, chucks, and the like can be employed.

  According to the radiation shielding fabric according to claim 1, warp and weft produced using a raw material for kneading of 20 to 90% by weight of a thermoplastic synthetic resin and 10 to 80% by weight of barium sulfate as the radiation shielding fabric. Therefore, the radiation shielding effect by barium sulfate can be obtained for the radioactive material covered with the radiation shielding fabric. Moreover, since the radiation shielding fabric is a cloth in which a tape yarn having a strength of 3.0 cN / dt or more is woven as warps and wefts, it has a higher elongation than a fabric made of general fibrous warps and wefts. . Thereby, the radiation shielding fabric is suitable as an original fabric of a radiation shielding flexible container bag in which a heavy object is stored.

  In particular, according to the radiation shielding woven fabric according to claim 2, when the content of barium sulfate is 30 to 50% by weight in the raw material for kneading, both the film formation and stretching of the thermoplastic synthetic resin are stabilized, and the radiation A shielded tape yarn is obtained.

  Moreover, according to the radiation shielding fabric of Claim 3, the weather resistance of a radiation shielding fabric can be improved by adding a weathering agent.

  According to the radiation shielding flexible container bag according to claim 4, because the radiation shielding fabric according to any one of claims 1 to 3 is adopted as an original fabric for the component sheet of the flexible container bag. Barium sulfate kneaded into the tape yarn shields part of the radiation. Thereby, the quantity which the radiation of the filled radioactive substance leaks out of a bag can be reduced.

  According to the radiation shielding cover of claim 5, since the radiation shielding fabric according to any one of claims 1 to 3 is adopted as a sheet material covering the radioactive substance storage body, for example, radioactive By covering the radiation shielding flexible container bag filled with the soil contaminated with the substance with the radiation shielding cover, the amount of radiation leaking out of the bag can be reduced as compared with the case of the radiation shielding flexible container bag alone.

According to the radiation shielding bag of claim 6, since the cloth lid having the radioactive substance shielding effect is provided on the bag body having the radioactive substance shielding effect via the wire fastener so as to be opened and closed, the filled radioactive substance The amount of radiation leaking out of the bag can be reduced. In addition, because the bag body uses a multi-layered inner bag sewn on the outer bag, and the cloth lid uses a multi-layered inner cloth sewn on the outer cloth, the radiation shielding bag is high. It becomes strength.
In addition, since the lid cloth is provided at the opening of the bag main body via the wire fastener, the opening and closing operation of the opening of the bag main body is easy, and the sealing performance of the bag main body by the lid cloth can be enhanced.

1 is a perspective view of a radiation shielding fabric according to an embodiment of the present invention. It is a principal part enlarged plan view of the radiation shielding fabric which concerns on the Example of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a whole block diagram of the manufacturing apparatus of the tape yarn used as the warp and weft of the radiation shielding fabric based on the Example of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall perspective view of a radiation shielding flexible container bag manufactured by adopting a radiation shielding fabric according to an embodiment of the present invention as an original fabric. It is a perspective view which shows the use condition of the radiation shielding cover produced using the radiation shielding textile which concerns on the Example of this invention. It is a perspective view which shows the partial opening state of the cover cloth of the radiation shielding bag produced using the radiation shielding fabric based on the Example of this invention.

Examples of the present invention will be specifically described below.
1 and 2, S is a radiation shielding fabric according to the present invention, and this radiation shielding fabric S is composed of 20 to 90% by weight of a thermoplastic synthetic resin (here, polypropylene) and 10 to 80% by weight of barium sulfate. This is a cloth (woven fabric) woven from the warp yarn 40 and the weft yarn 41 using a tape yarn having a strength of 3.0 cN / dt or more produced using the blend (raw material for kneading) as the warp yarn 40 and the weft yarn 41.
Polypropylene is a homopolymer of propylene, or a propylene-based one, and α-olefins such as ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and acrylic acid. Random copolymers, block copolymers, or graft copolymers with unsaturated carboxylic acids such as ethyl acrylate and derivatives thereof, vinyl esters such as vinyl acetate, unsaturated aromatic compounds such as styrene and methylstyrene, etc. Coalescence can be mentioned.
The melt flow rate of the polypropylene resin (measured according to JIS K 7210-1976 “Thermoplastic Plastic Flow Test Method”, Condition 14, Table 1, Test Temperature 230 ?, Test Load 21.18 N, hereinafter referred to as MFR) is not particularly limited. However, if it is 0.1 to 10 g / 10 min, preferably 0.5 to 5 g / 10 min, the extrusion yarn is good and the strength of the obtained tape yarn is sufficient, which is desirable.

As shown in FIG. 3, in the production of the radiation shielding fabric S, first, a main raw material a made of polypropylene and a radiation shielding raw material b made of barium sulfate are composed of 20 to 90% by weight of the main raw material a. The raw material mixer 30 is charged with a blending ratio (inner split) in which the shielding raw material b is 10 to 80% by weight. In order to improve the weather resistance of the radiation shielding fabric S, at least one additive c selected from a light stabilizer and an ultraviolet absorber is added to the raw material mixer 30 with respect to the mixture of the raw materials a and b. And 0.1 to 2.0% by weight may be added.
In the raw material mixer 30, both raw materials a, b, and c are mixed to obtain a blend (raw material for kneading) d. Thereafter, the compound d is put into a T-die extruder 31 where a wide film 32 is continuously formed while melting both raw materials a, b and c.

  The surface of the obtained film 32 is provided with the cutting edges of a large number of cutters 33 arranged at a fixed pitch in the weft direction of the film 32, and the film 32 is slit into a plurality of thick tapes. 32a. Next, downstream from the installation position of each cutter 33, the tape-like object 32a is stretched in the warp direction (the length direction of the tape) on the heated arc-shaped hot plate 34, and then the arc-shaped heat is applied. Many tape yarns Y are manufactured by annealing each tape-like product 32b drawn by the plate 35.

  Thereafter, the obtained tape yarns Y are warped into beams, and the tape yarn Y is then woven as a warp 40 and a weft 41 by an automatic loom (weaving device), whereby the radiation shielding fabric S is obtained. At the time of weaving, the warp 40 and the weft 41 are woven without any gaps (densely) (FIG. 2). The radiation shielding fabric S manufactured in this way can be employed as an original fabric for a flexible container bag, for example. In addition, it can also be used as curtains, curtains, grass protection sheets, covers and the like.

  Thus, as the radiation shielding fabric S, a cloth obtained by weaving a tape yarn Y using a blend d of a main raw material a made of a thermoplastic synthetic resin and a radiation shielding raw material b made of barium sulfate as a raw material is adopted. The radiation shielding raw material b contained in the material shields a part of the radiation covered by the radiation shielding fabric S, for example, from radioactive substances in the contaminated topsoil. Therefore, the amount of radiation leaking out of the radiation shielding fabric S can be reduced. Further, since the warp 40 and the weft 41 of the radiation shielding fabric S are woven without gaps (FIG. 2), the strength is higher than that of a general fabric composed of the fibrous warp 40 and the weft 41, and from the gaps. Since radiation is difficult to leak, the amount of radiation leaking out of the flexible container bag can be further reduced.

Next, with reference to FIG. 4, another radiation shielding flexible container bag (hereinafter, flexible container bag) according to the present invention will be described.
As shown in FIG. 4, the flexible container bag 10 has a plurality of component sheets obtained by cutting the raw fabric A (FIG. 1) made of the radiation shielding fabric S, and adjacent ones of the plurality of component sheets. Made by sewing.

Hereinafter, these components will be specifically described.
The flexible container bag 10 is sewn at the upper end of the trunk portion 11 with a bag body 13 having a trunk portion 11 whose upper end is open, and a bottom portion 12 that is sewn to and closes the lower end of the trunk portion 11. A cylindrical charging portion 15 for loading contaminated top soil (radioactive material) shaved from soil contaminated with the substance into the trunk portion 11, a square reinforcing cloth frame 16 sewn on the bottom surface of the bottom portion 12, and reinforcement Four suspension belts 17 whose lower ends are connected to the four corners of the cloth frame 16 and two upper ends of one set and two adjacent groups are connected, and the upper end of each suspension belt 17 is connected to the body 11. Reinforcing cloth 18 for sewing to the upper end of the bag, two suspension ropes 19 spanned between the upper end portions of each set of the suspension belt 17, and a synthetic resin ( Here, an inner bag 20 made of polyvinyl chloride) is provided.

The flexible container bag 10 here is, for example, a round bag having an internal capacity of 1.0 m ³ . Among these, the trunk portion 11 and the bottom portion 12 constituting the bag body 13, the input portion 15, the reinforcing cloth frame 16, the suspension belt 17, and the reinforcing cloth 18 are the original material woven from the tape yarn Y shown in FIG. This is a component sheet obtained by cutting anti-A into a predetermined shape.
At the time of cutting the component sheet including the body portion 11 and the bottom portion 12, the raw fabric A made of the radiation shielding fabric S is sent to a cutting machine, where the body portion 11 and the bottom portion 12 are cut out of the raw fabric A by laser cutting or the like. Cut.
Each component sheet including the obtained body portion 11 and the bottom portion 12 uses an electric sewing machine, and the adjacent ones are sewn together, whereby the flexible container bag 10 is manufactured.

  When the bag is used, the flexible container bag 10 is transported to the site by a truck or the like. At the site, for example, contaminated topsoil contaminated with a radioactive substance (such as radioactive cesium) is scraped off by a yumbo, and this is sequentially filled into the inner bag 20 of the opened flexible container bag 10. After the filling is completed, the operator binds the opening of the inner bag 20 and further binds the input unit 15 with a binding string. Thereafter, the operator hooks each suspension rope 19 of the flexible container bag 10 on the bucket of the Yumbo, and the driver of the Yumbo rotates the arm upward to lift the flexible container bag 10 and loads it on the truck bed. Thereafter, the truck travels on the road and transports it to a predetermined storage location, where the flexible container bag 10 is lowered and stored for a predetermined period.

  Thus, as the raw fabric A, the radiation shielding fabric S obtained by weaving the tape yarn Y using the blend d of the main raw material a made of thermoplastic synthetic resin and the radiation shielding raw material b made of barium sulfate as the raw material is used. The radiation shielding raw material b kneaded into the yarn Y shields a part of the radiation contained in the contaminated topsoil. Therefore, the amount of radiation leaking out of the flexible container bag 10 from the contaminated topsoil filled in the inner bag 20 can be reduced. Further, since the warp 40 and the weft 41 of the radiation shielding fabric S are woven without gaps (FIG. 2), the tensile strength is higher than that of a fabric composed of general fibrous warps and wefts, and from the gaps. Since radiation is difficult to leak, the amount of radiation leaking out of the flexible container bag 10 can be further reduced.

Next, another radiation shielding cover according to the present invention will be described with reference to FIG.
As shown in FIG. 5, the radiation shielding cover 50 is made of the radiation shielding fabric S and covers a large number of flexible container bags 10 stored in a predetermined temporary storage place, so that the outside of the bag is covered. The amount of radiation to leak can be reduced as compared with the case of the flexible container bag 10 alone.

Next, the radiation shielding bag according to the present invention will be described with reference to FIG.
As shown in FIG. 6, the radiation shielding bag 60 is an alternative to the inner bag 20 of the flexible container bag 10 shown in FIG. 4, and the outer bag 61 obtained from the raw fabric A made of the radiation shielding fabric S. And a bag body 65 produced by sewing an inner bag 64 in which a radiation shielding metal foil layer 63 is laminated on a transparent synthetic resin base film layer 62, and an opening of the bag body 65 through a wire fastener 66. And an outer cloth 67 obtained from an original fabric A made of a radiation shielding fabric S and an inner cloth 68 in which a radiation shielding metal foil layer 63 is laminated on a transparent synthetic resin base film layer 62. And a cloth lid 69 prepared by wearing.

Thus, since the radiation shielding bag 60 is used as the inner bag 20 of the flexible container bag 10, the radiation shielding effect of the flexible container bag 10 can be further enhanced, and it is stored in the bag body 13 during use and is not exposed to sunlight. Therefore, it is not necessary to add a weathering agent to the main raw material of the tape yarn Y, and it is possible to prevent a decrease in strength of the original fabric due to the addition of the weathering agent.
The bag body 65 is a circular round shape in plan view with the entire upper surface open, and the cloth lid 69 is a circular shape in plan view having a diameter substantially the same as the opening diameter of the bag main body 65. 66 is provided over the entire upper edge of the bag body 65 and the entire outer edge of the cloth lid 69. Thus, by simply sliding the line fastener 66 along the opening edge of the bag main body 65 while ensuring the maximum opening on the upper surface of the bag main body 65 so that the filling (such as contaminated topsoil) can be easily put into the bag, The cloth lid 69 can be opened and closed easily and reliably. Moreover, the workability of opening and closing the cloth lid 69 is higher than that of fastening the inner bag using a conventional string.

  The inner bag 64 and the inner cloth 68 are made of a sheet having a three-layer structure in which one radiation shielding metal foil layer 63 made of aluminum foil is sandwiched between two transparent synthetic resin base film layers 62. . Therefore, in the inner bag 64 and the inner cloth 68, the synthetic resin base film layer 62 disposed on the inner side of the bag serves as a protective film, and, for example, the radiation shielding metal foil layer 63 comes into contact with the filler when filling the filler. It is possible to prevent the radiation shielding effect from being reduced. Moreover, the radiation shielding bag 60 of the present invention employs a configuration in which the metallic gloss surface of the radiation shielding metal foil layer 63 is exposed through the transparent synthetic resin base film layer 62 in the inner space of the bag body 65. . Therefore, even in a poor working environment where only a small amount of light can be obtained, such as in a dark place or at night, the inner surface of the bag body 65 ( Light is diffusely reflected by the fungus image glossy surface, and the entire inner surface of the bag can be illuminated by this light. As a result, the operator who moves heavy machinery (yumbo) at the site of scraping contaminated topsoil in the dark or at night makes it easier to visually recognize the opening position of the bag body 65, and the accuracy of bagging of the contaminated topsoil at night etc. Each work efficiency can be improved.

Further, the bag main body 65 includes an outer bag 61 obtained from the raw fabric A made of the radiation shielding fabric S and an inner bag in which the radiation shielding metal foil layer 63 is laminated on the transparent synthetic resin base film layer 62. 64 is sewn and has high shape retention as a bag (with a feeling of stickiness), and the radiation shielding bag 60 can be made self-supporting even without a bag self-supporting aid. Bagging can be performed.
As the tape yarn Y for raw material, for example, a main raw material a made of polypropylene and a radiation shielding raw material b made of barium sulfate are mixed in such a ratio that the main raw material a is 70% by weight and the radiation shielding raw material b is 30% by weight. Those made from the combined formulation d can be employed.
The wire fastener 66 moves the slider between a pair of left and right base tapes in which a large number of elements (service teeth) are arranged in a row, whereby the left and right elements are sequentially meshed or released, and the fastener can be freely opened and closed. This is a linear hook. As the wire fastener 66, a plastic fastener having higher weather resistance than that of a metal fastener is employed.

When the radiation shielding bag 60 is used, for example, contaminated topsoil scraped off by the yumbo is sequentially filled into the radiation shielding bag 60 in the flexible container bag 10 in which the cloth fastener 66 is removed and the cloth lid 69 is opened. After filling, the operator closes the line fastener 66, closes the opening of the radiation shielding bag 60, and further binds the input portion 15 with a binding string.
As described above, according to the radiation shielding bag 60, the bag body 65 having the radioactive substance shielding effect is provided with the cloth lid 69 having the radioactive substance shielding effect through the wire fastener 66 so as to be freely opened and closed. The amount of radioactive material radiation leaking out of the bag can be reduced. In addition, the bag body 65 employs a multi-layer structure inner bag 64 sewn to the outer bag 61, and the cloth cover 69 employs a multi-layer structure inner cloth 68 sewn to the outer cloth 67. The radiation shielding bag 60 becomes high in strength and the radiation shielding bag 60 becomes appropriately hard, so that the self-supporting property of the radiation shielding bag 60 and the self-supporting property of the flexible container bag 10 can be improved.
In addition, since the cloth lid 69 is provided at the opening of the bag body 65 via the wire fastener 66, the opening and closing operation of the opening of the bag body 65 is easy, and the sealing of the bag body 65 by the cloth lid 69 is achieved. Can be increased.

  Next, in order to confirm how the increase or decrease in the amount of barium sulfate added affects the performance of barium sulfate in the radiation shielding fabric of the present invention: 1. radiation shielding test; 2. Textile strength test; A weather resistance test was conducted, and the results are shown in Table 1 (Test Examples 1 to 11 and Comparative Examples 1 to 3). Each test method and the evaluation method of each test are as follows.

1. Radiation shielding test method At a height of 1 m from the floor, the detector is separated from the radiation source to the measurement center by 25 cm, and there is a net when there is a sample (with sample) and when there is no sample (without sample). The dose rate (removing the background dose rate) is measured 10 times, and the shielding rate is obtained from the average value of the measured values.
Radiation source: Cesium 137 Radiation source 10MBq (as of December 16, 2009)
Japan Isotope Association radiation dose rate standard gamma ray source CS454CE (source number 8101)
Measuring instrument: NaI (Tl) scintillation survey meter Aroka TCS-171B
Background dose rate = 0.04 ± 0.01 μSv / hr
Dose rate when no sample is present = 15.7 ± 0.1 μSv / hr
Shielding rate = (1−with sample / without sample) × 100
It is.
-Evaluation method of radiation shielding Since general synthetic resins of polyethylene and polypropylene do not have a radiation shielding function, the presence or absence of a shielding effect by adding barium sulfate was evaluated.

2. Test method for fabric strength and elongation test method for fabrics and knitted fabrics JIS L 1096-2010, 8.14 Tensile strength and elongation method A (strip method).
-Evaluation method of fabric strong elongation test Flexible container for non-dangerous goods It evaluated in comparison with the strong elongation required as a main body material of JISZ1651-2008.

3. Weather resistance test method Sunshine carbon arc lamp type light resistance tester and weather resistance tester JIS B 7753-2007.
-Weather resistance evaluation method Weather resistance test The residual strength ratio after 900 hours of irradiation was evaluated as 70% or more of the initial strength.

Next, the implemented test examples 1 to 11 and comparative examples 1 to 3 performed for comparison will be described.
[Test Example 1]
First, the tape yarn Y is manufactured using the tape yarn manufacturing equipment shown in FIG. That is, a main raw material a made of polypropylene in the form of pellets (polypropylene resin is a single polymer, MFR, 0.8 g / 10 min) is used, and a radiation shielding raw material b made of powdered barium sulfate is used as a main raw material a. 90 wt% and the radiation shielding raw material b is blended so as to be 10 wt% into a raw material mixer to obtain a blend d. Thereafter, the compound d is put into a T-die extruder 31, and a wide film 32 is continuously formed at a T-die temperature of 240 ° C. while kneading both raw materials a and b. Next, the film 32 is slit with a cutter 33 to obtain a large number of thick tapes 32a, which are then stretched in the warp direction on an arc-shaped hot plate 34 heated to 140 ° C., Further, the tape-like product 32b after stretching was annealed by an arc-shaped hot plate 35 at 140 ° C. to obtain a large number of tape yarns Y. Thereafter, each tape yarn Y is warped into a beam, and then the radiation shielding fabric S is woven by an automatic loom using the tape yarn Y as the warp 40 and the weft 41 (FIGS. 1 and 2).
The radiation shielding fabric S was subjected to a radiation shielding test, a fabric strength elongation test, and a weather resistance test. The results are shown in Table 1.

[Test Example 2]
In Test Example 2, in the production process of the tape yarn Y, the main raw material was set to 80% by weight, the radiation shielding raw material b was set to 20% by weight and charged into the raw material mixer to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 3]
In Test Example 3, in the production process of Tape Yarn Y, the main raw material was set to 70% by weight, the radiation shielding raw material b was set to 30% by weight and charged into the raw material mixer to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 4]
In Test Example 4, in the production process of Tape Yarn Y, the main raw material was set to 60% by weight, the radiation shielding raw material b was set to 40% by weight, and the raw material was mixed to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 5]
In Test Example 5, in the production process of Tape Yarn Y, the main raw material was set to 50% by weight and the radiation shielding raw material b was set to 50% by weight into the raw material mixer to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 6]
In Test Example 6, in the production process of the tape yarn Y, the main raw material was set to 40% by weight, the radiation shielding raw material b was set to 60% by weight, and charged into the raw material mixer to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 7]
In Test Example 7, in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, a product (compound) in which these raw materials a and b are mixed, A test piece of radiation shielding fabric S was obtained in the same manner as in Test Example 1, except that the weathering agent c was 0.2% by weight and was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[Test Example 8]
In Test Example 8, in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, the raw material a and b were mixed (mixture). A test piece of radiation shielding fabric S was obtained in the same manner as in Test Example 1, except that 0.4% by weight of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[Test Example 9]
In Test Example 9, in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, in addition to the mixture (mixture) of these raw materials a and b A test piece of radiation shielding fabric S was obtained in the same manner as in Test Example 1, except that 0.6 wt% of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[Test Example 10]
In Test Example 10, in the production process of the tape yarn Y, in addition to 70% by weight of the main raw material a and 30% by weight of the radiation shielding raw material b, the product (compound) in which these raw materials a and b were mixed was added. A test piece of radiation shielding fabric S was obtained in the same manner as in Test Example 1, except that 1.0% by weight of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[Test Example 11]
In Test Example 11, in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, the material (compound) in which these raw materials a and b are mixed is added. A test piece of radiation shielding fabric S was obtained in the same manner as in Test Example 1, except that 2.0% by weight of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[Comparative Example 1]
In Comparative Example 1, a test piece of radiation shielding fabric S was prepared in the same manner as in Test Example 1, except that only the main raw material a was introduced into the raw material mixer in the production process of the tape yarn Y to obtain the compound d. Got. The results are shown in Table 1.

[Comparative Example 2]
Comparative Example 2 was a test example except that in the production process of tape yarn Y, the main raw material was 95% by weight and the radiation shielding raw material b was 5% by weight, which was charged into the raw material mixer to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Comparative Example 3]
In Comparative Example 3, in the production process of the tape yarn Y, the main raw material was set to 30% by weight and the radiation shielding raw material b was set to 70% by weight, but the film was not formed. The results are shown in Table 1.

As can be seen from Table 1, the radiation shielding effect increased as the amount of barium sulfate added in the blend (raw material k) d increased, but the fabric strength and elongation decreased. However, when the addition amount of barium sulfate was 10 to 80% by weight, both the radiation shielding effect and the fabric strong elongation were evaluated as raw materials for the flexible container bag 10. In particular, when the addition amount of barium sulfate is 30 to 50% by weight, for example, when the radiation shielding fabric S is used as the raw fabric A for the flexible container bag 10, a suitable radiation shielding effect and fabric strength are obtained. Obtained.
As for the weather resistance, good results are obtained when the amount of the weathering agent in the formulation d is 0.2 to 2.0% by weight, particularly when the amount is 0.6 to 2.0% by weight. Optimum weather resistance was obtained.

  The present invention is useful, for example, as a technique for storing and transporting contaminated topsoil contaminated with radioactive substances.

10 Radiation shielding flexible container bag,
50 radiation shielding cover,
60 radiation shielding bags,
61 Outer bag,
62 synthetic resin base film layer,
63 radiation shielding metal foil layer,
64 inner bag,
65 bag body,
66 line fastener,
67 Outer cloth,
68 Inner cloth,
69 cloth lids,
S radiation shielding fabric,
Y tape yarn,
a Main raw material (thermoplastic synthetic resin),
b Radiation shielding material (barium sulfate),
c Additives (weatherproofing agents),
d Formulation (raw material for kneading).

The present invention relates to a radiation shielding flexible container bag and a radiation shielding bag manufactured using a radiation shielding fabric containing barium sulfate which is a kind of radiation shielding raw material .

With the accident at TEPCO's Fukushima Daiichi Nuclear Power Station on March 11, 2011, a wide range of soils, mainly in Fukushima Prefecture, are contaminated with radioactive materials. The area of soil contamination is large, and the Ministry of Agriculture, Forestry and Fisheries is working on the development of decontamination technology for the soil that is the basis of food production. As part of this, in Fukushima Prefecture, taking into account the ground (paddy fields, fields) and the degree of contamination, topsoil (filler) is scraped from soil with a radioactive cesium concentration of 5000 Bq / kg or more.
Specifically, the topsoil is scraped off by heavy machinery (yumbo), filled into a flexible container bag, transported to a predetermined temporary storage location, and stored until moving to an intermediate storage facility installed in the future. . In the temporary storage method, a flexible container bag filled with contaminated soil is covered with a water shielding sheet or the like.

Utility Model Registration No. 3173174

  By the way, a conventional flexible container bag cuts a plurality of raw fabrics woven with a tape yarn made of thermoplastic resin such as polyethylene and polypropylene into component sheets of a predetermined shape, and then sews adjacent component sheets together. It has a bag shape and does not have a radiation shielding function. Therefore, a large amount of radiation from the contaminated soil leaks outward from the flexible container bag, which increases the level of radioactive contamination of workers engaged in long-term work not only at the site of topsoil cutting but also at the storage location. Had occurred.

Therefore, as a result of diligent research, the inventor has formed a raw material for kneading of 50 to 70% by weight of a thermoplastic synthetic resin and 30 to 50% by weight of barium sulfate as a raw material from which a component sheet of a flexible container bag is cut. By adopting a radiation shielding fabric woven from slits, heat-stretched tape yarns, a radiation shielding flexible container bag that is lightweight and flexible and is not easily torn even when sharp objects are pierced can be obtained. As a result, the present invention was completed.

An object of the present invention is to provide a radiation shielding flexible container bag and a radiation shielding bag which have high strength and can reduce the amount of external leakage of radiation of a covered radioactive substance .

The invention according to claim 1 uses a raw material for kneading of 50 to 70% by weight of a thermoplastic synthetic resin and 30 to 50% by weight of barium sulfate, and produces a tape yarn having a strength of 3.0 cN / dt or more. Radiation shielding flexible made by weaving the raw fabric from this tape yarn and cutting the raw fabric to produce a plurality of component sheets, and sewing these adjacent component sheets together It is a container bag .

The raw material for kneading here is a raw material for producing a tape yarn used when weaving a radiation shielding fabric, and specifically includes various thermoplastic synthetic resins and barium sulfate.
Examples of the thermoplastic synthetic resin that is the main raw material for kneading include polypropylene, polyethylene, vinyl chloride, nylon, and polyester. Among these, for example, polypropylene that can ensure the strength, elongation, and durability required for the flexible container bag is preferable. Examples of the properties of the thermoplastic synthetic resin include pellets, granules, and powders.

Barium sulfate is harmless to the human body, and is taken as a contrast agent for digestive organs during, for example, an in-vivo examination using X-rays. Also, the impact on the environment is very small compared to lead.
Precipitating barium sulfate is preferable because of compatibility with the thermoplastic resin.
The property of barium sulfate is arbitrary, for example, powdery or liquid. However, the property of barium sulfate is preferable because it is easy to knead with the main raw material. In that case, the average particle size of the powdered barium sulfate is 10 μm or less, preferably 5 μm or less. If it exceeds 10 μm, it is difficult to uniformly disperse in film formation, and problems such as fish eyes occur. Moreover, the kneading raw material is slit into a predetermined width after film formation, and is heated and stretched to form a tape yarn. However, if the average particle size of the barium sulfate powder exceeds 10 μm, the yarn is easily cut during stretching. Become.

The amount of barium sulfate added is 30-50% by weight based on 100% by weight of the kneading raw material. Correspondingly, the amount of the thermoplastic synthetic resin added is 50 to 70% by weight based on 100% by weight of the raw material for kneading .

  A raw material for kneading may be mixed with a radiation shielding raw material different from barium sulfate or a substance (additive) having no radiation shielding effect. As different radiation shielding materials, for example, tungsten, bismuth, cerium and the like can be employed. Examples of additives include various additives used for thermoplastic resins, such as antioxidants, light stabilizers, ultraviolet absorbers, neutralizers, lubricants, blocking agents, flame retardants, and pigments.

The tape yarn is generally produced by forming a film from a thermoplastic synthetic resin as a raw material, forming a plurality of slits in the film to form a tape, and then stretching each tape while heating. The tape yarn is made by weaving warps and wefts without any gaps (densely) so that a radiation shielding fabric having a high radiation shielding effect is woven.
When the strength of the tape yarn is 3 cN / dt or less, sufficient strength as a flexible container fabric cannot be obtained.

  When the content of barium sulfate in the kneading raw material is less than 30% by weight, it is difficult to obtain a shielding effect. On the other hand, if it exceeds 50% by weight, uniform dispersion with the thermoplastic resin becomes difficult, film formation and heat stretching are not stable, and it is difficult to obtain a tape yarn having sufficient strength for a radiation shielding fabric.

In addition, when radiation shielding fabrics are used as raw materials for flexible container bags and raw materials (raw fabrics) for radiation shielding covers, they are often used outdoors, so they are exposed to sunlight for a long period of time, thus providing high weather resistance. Is needed. As a method for improving the weather resistance, addition of a light stabilizer, an ultraviolet absorber and carbon black can be employed. The added amount is at least one selected from light stabilizers and ultraviolet absorbers, and is 0.1 to 2.0% by weight on the basis of 100% by weight of the raw material for kneading (total in the case of multiple types) % By weight).

  As a hindered amine light stabilizer which is a kind of light stabilizer, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) ) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) .di (tridecyl) -1,2,3,4-butanetetracarboxylate And polycondensates of 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and diethyl succinate. Examples of UV absorbers include 2-ethylhexyl-2-cyano-3,3′-diphenyl acrylate, ethyl-2-cyano-3,3′-diphenyl acrylate, octyl-2-cyano-3,3′-diphenyl acrylate Cyanoacrylate ultraviolet absorbers such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, benzophenone ultraviolet absorbers such as 2-hydroxy-4-octoxybenzophenone, 2- (2′-hydroxy- 5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole and other benzotriazole ultraviolet absorbers, resorcinol monobenzoate, 2,4-di-t-butylphenyl -3′-5′-di-t-butyl-4′- Mud carboxymethyl benzoate-based ultraviolet absorbers such as benzoate and the like.

The use of the radiation shielding flexible container bag is not limited. For example, it is suitable for outdoor work, especially for transportation and storage of contaminated soil (contaminated topsoil) contaminated with radioactive substances.
A flexible container bag is a bag (cloth) made of tape yarn made mainly of polypropylene or the like. The bottom of the bag body or the trunk is sewn to the lower end of the suspension belt. A cylindrical charging part for charging the filler into the body part is sewn on the (upper peripheral part).
As the bag main body, a general one in which a cloth having a dense warp and weft (no gap) is sewn so as to prevent the filler (particularly contaminated soil) from leaking. In addition, you may employ | adopt the bag main body which provided the draining function by making yarn density low.

As the external shape of the bag body, for example, a circular round shape in a plan view, a square shape in a plan view, and the like can be adopted.
The radiation shielding flexible container bag may have an inner bag. As the inner bag, for example, a bag made of synthetic resin such as polyethylene can be employed. The inner bag may be double or triple or more. Further, the radiation shielding fabric of the present invention can be sewn into a cylindrical shape or a bag shape and used as an inner bag.
As an input part, what sewn cloth (radiation shielding textiles) in the shape of a cylinder, or what processed various synthetic resin sheets into the shape of a cylinder, etc. are also employable.
In addition, a drawstring type, in which a fastening string is attached to the upper peripheral edge of the input part so that the input part (saddle part) can be narrowed down, is a general input part. A belt may be used to tie the opening of the charging portion.

As used herein, the “ raw fabric” refers to a tape yarn having a strength of 3.0 cN / dt or more made from a raw material for kneading 50 to 70% by weight of a thermoplastic synthetic resin and 30 to 50% by weight of barium sulfate . A cloth (radiation shielding fabric) woven using warp and weft.
The “component sheet” cut from the original fabric here is at least the trunk and the bottom constituting the bag body. In addition, an insertion portion provided around the upper end of the trunk portion, a suspension belt sewn on the trunk portion, a reinforcing cloth (frame) for reinforcing the connection of the suspension belt to the bag body, and the like may be included.
A radiation shielding film such as an aluminum film may be laminated on at least one of the front and back surfaces of the component sheet. Thereby, the radiation shielding effect of the radiation shielding flexible container bag is further enhanced.

The use of the radiation shielding cover is arbitrary. For example, it can be used as a cover for covering a flexible container bag filled with radioactively contaminated soil (radiation shielding).
The shape and size of the radiation shielding cover are arbitrary.

The invention according to claim 2 is a bag body produced by sewing an inner bag in which a radiation shielding metal foil layer is laminated on a synthetic resin base film layer on an outer bag obtained from a raw fabric, An inner cloth in which the radiation shielding metal foil layer is laminated on the synthetic resin base film layer is sewn to the outer cloth provided in the opening of the bag body through a fastener and obtained from the original fabric. A radiation shielding bag provided with a cloth lid manufactured by using a raw material for kneading of 50 to 70% by weight of a thermoplastic synthetic resin and 30 to 50% by weight of barium sulfate. A radiation shielding bag in which a tape yarn of 0 cN / dt or more is used, and the raw fabric is woven from the tape yarn .

The use of the radiation shielding bag is arbitrary. For example, in addition to being used as a general bag filled with a radioactive substance, it may be used as an inner bag of a flexible container bag (including the radiation shielding flexible container bag according to claim 1 ). When used as an inner bag, the radiation shielding effect of the radiation shielding flexible container bag can be further enhanced, and since it is not exposed to sunlight for a long time, the main raw material (synthetic resin) of tape yarn for weaving the raw fabric There is no need to add a weathering agent, and the strength of the original fabric can be prevented from decreasing due to the addition of the weathering agent.
As the external shape of the bag body, for example, a circular round shape in a plan view and a square shape in a plan view can be adopted.
As the raw fabric for the outer bag and the raw fabric for the outer fabric, for example, the original fabric described in claim 4 can be adopted.

As a material for the synthetic resin base film layer, for example, polyethylene, polypropylene, or the like can be employed. The synthetic resin base film layer for the inner bag and the synthetic resin base film layer for the inner cloth may be the same material or different materials.
As the radiation shielding metal foil layer, for example, an aluminum foil or the like can be employed. The radiation shielding metal foil layer for the inner bag and the composite radiation shielding metal foil layer for the inner fabric may be the same material or different materials.
The number of laminated layers of the synthetic resin base film layer and the radiation shielding metal foil layer is arbitrary. As the number of these layers increases, the strength of the bag body and the cloth lid increases, and the self-supporting property of the radiation shielding bag increases, and the work of holding the opening of the radiation shielding bag during filling of the radioactive substance becomes easier.
As the line fastener (slide fastener), for example, various zippers, chucks, and the like can be employed.

As the radiation shielding fabric, weaved warp and weft made using a kneading raw material of thermoplastic synthetic resin 50 to 70% by weight and barium sulfate 30 to 50% by weight. A radiation shielding effect by barium sulfate is obtained for the radioactive material covered. Moreover, since the radiation shielding fabric is a cloth in which a tape yarn having a strength of 3.0 cN / dt or more is woven as warps and wefts, it has a higher elongation than a fabric made of general fibrous warps and wefts. . Thereby, the radiation shielding fabric is suitable as an original fabric of a radiation shielding flexible container bag in which a heavy object is stored.

In particular, when the content of barium sulfate is 30 to 50% by weight in the kneading raw material, both film formation and stretching of the thermoplastic synthetic resin are stable, and a radiation shielding tape yarn is obtained.

Moreover, the weather resistance of a radiation shielding textile can be improved by adding a weather resistance agent .

According to the radiation shielding flexible container bag of claim 1, since the radiation shielding fabric is adopted as the raw material for the component sheet of the flexible container bag, the barium sulfate kneaded into the tape yarn shields a part of the radiation. To do. Thereby, the quantity which the radiation of the filled radioactive substance leaks out of a bag can be reduced.

According to the radiation shielding bag of claim 2, since the cloth lid having the radioactive substance shielding effect is provided on the bag body having the radioactive substance shielding effect via the wire fastener so as to be opened and closed, the filled radioactive substance The amount of radiation leaking out of the bag can be reduced. In addition, because the bag body uses a multi-layered inner bag sewn on the outer bag, and the cloth lid uses a multi-layered inner cloth sewn on the outer cloth, the radiation shielding bag is high. It becomes strength.
In addition, since the lid cloth is provided at the opening of the bag main body via the wire fastener, the opening and closing operation of the opening of the bag main body is easy, and the sealing performance of the bag main body by the lid cloth can be enhanced.

1 is a perspective view of a radiation shielding fabric according to an embodiment of the present invention. It is a principal part enlarged plan view of the radiation shielding fabric which concerns on the Example of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a whole block diagram of the manufacturing apparatus of the tape yarn used as the warp and weft of the radiation shielding fabric based on the Example of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall perspective view of a radiation shielding flexible container bag manufactured by adopting a radiation shielding fabric according to an embodiment of the present invention as an original fabric. It is a perspective view which shows the use condition of the radiation shielding cover produced using the radiation shielding textile which concerns on the Example of this invention. It is a perspective view which shows the partial opening state of the cover cloth of the radiation shielding bag produced using the radiation shielding fabric based on the Example of this invention.

Examples of the present invention will be specifically described below.
1 and 2, S is a radiation shielding fabric according to the present invention, and this radiation shielding fabric S is composed of 20 to 90% by weight of a thermoplastic synthetic resin (here, polypropylene) and 10 to 80% by weight of barium sulfate. This is a cloth (woven fabric) woven from the warp yarn 40 and the weft yarn 41 using a tape yarn having a strength of 3.0 cN / dt or more produced using the blend (raw material for kneading) as the warp yarn 40 and the weft yarn 41.
Polypropylene is a homopolymer of propylene, or a propylene-based one, and α-olefins such as ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and acrylic acid. Random copolymers, block copolymers, or graft copolymers with unsaturated carboxylic acids such as ethyl acrylate and derivatives thereof, vinyl esters such as vinyl acetate, unsaturated aromatic compounds such as styrene and methylstyrene, etc. Coalescence can be mentioned.
The melt flow rate of the polypropylene resin (measured according to JIS K 7210-1976 “Thermoplastic Plastic Flow Test Method”, Condition 14 in Table 1, Test Temperature 230 ° C., Test Load 21.18 N), hereinafter referred to as MFR) is not particularly limited. However, if it is 0.1 to 10 g / 10 min, preferably 0.5 to 5 g / 10 min, the extrusion yarn is good and the strength of the obtained tape yarn is sufficient, which is desirable.

As shown in FIG. 3, in the production of the radiation shielding fabric S, first, a main raw material a made of polypropylene and a radiation shielding raw material b made of barium sulfate are composed of 20 to 90% by weight of the main raw material a. The raw material mixer 30 is charged with a blending ratio (inner split) in which the shielding raw material b is 10 to 80% by weight. In order to improve the weather resistance of the radiation shielding fabric S, at least one additive c selected from a light stabilizer and an ultraviolet absorber is added to the raw material mixer 30 with respect to the mixture of the raw materials a and b. And 0.1 to 2.0% by weight may be added.
In the raw material mixer 30, both raw materials a, b, and c are mixed to obtain a blend (raw material for kneading) d. Thereafter, the compound d is put into a T-die extruder 31 where a wide film 32 is continuously formed while melting both raw materials a, b and c.

  The surface of the obtained film 32 is provided with the cutting edges of a large number of cutters 33 arranged at a fixed pitch in the weft direction of the film 32, and the film 32 is slit into a plurality of thick tapes. 32a. Next, downstream from the installation position of each cutter 33, the tape-like object 32a is stretched in the warp direction (the length direction of the tape) on the heated arc-shaped hot plate 34, and then the arc-shaped heat is applied. Many tape yarns Y are manufactured by annealing each tape-like product 32b drawn by the plate 35.

  Thereafter, the obtained tape yarns Y are warped into beams, and the tape yarn Y is then woven as a warp 40 and a weft 41 by an automatic loom (weaving device), whereby the radiation shielding fabric S is obtained. At the time of weaving, the warp 40 and the weft 41 are woven without any gaps (densely) (FIG. 2). The radiation shielding fabric S manufactured in this way can be employed as an original fabric for a flexible container bag, for example. In addition, it can also be used as curtains, curtains, grass protection sheets, covers and the like.

  Thus, as the radiation shielding fabric S, a cloth obtained by weaving a tape yarn Y using a blend d of a main raw material a made of a thermoplastic synthetic resin and a radiation shielding raw material b made of barium sulfate as a raw material is adopted. The radiation shielding raw material b contained in the material shields a part of the radiation covered by the radiation shielding fabric S, for example, from radioactive substances in the contaminated topsoil. Therefore, the amount of radiation leaking out of the radiation shielding fabric S can be reduced. Further, since the warp 40 and the weft 41 of the radiation shielding fabric S are woven without gaps (FIG. 2), the strength is higher than that of a general fabric composed of the fibrous warp 40 and the weft 41, and from the gaps. Since radiation is difficult to leak, the amount of radiation leaking out of the flexible container bag can be further reduced.

Next, with reference to FIG. 4, another radiation shielding flexible container bag (hereinafter, flexible container bag) according to the present invention will be described.
As shown in FIG. 4, the flexible container bag 10 has a plurality of component sheets obtained by cutting the raw fabric A (FIG. 1) made of the radiation shielding fabric S, and adjacent ones of the plurality of component sheets. Made by sewing.

Hereinafter, these components will be specifically described.
The flexible container bag 10 is sewn at the upper end of the trunk portion 11 with a bag body 13 having a trunk portion 11 whose upper end is open, and a bottom portion 12 that is sewn to and closes the lower end of the trunk portion 11. A cylindrical charging portion 15 for loading contaminated top soil (radioactive material) shaved from soil contaminated with the substance into the trunk portion 11, a square reinforcing cloth frame 16 sewn on the bottom surface of the bottom portion 12, and reinforcement Four suspension belts 17 whose lower ends are connected to the four corners of the cloth frame 16 and two upper ends of one set and two adjacent groups are connected, and the upper end of each suspension belt 17 is connected to the body 11. Reinforcing cloth 18 for sewing to the upper end of the bag, two suspension ropes 19 spanned between the upper end portions of each set of the suspension belt 17, and a synthetic resin ( Here, an inner bag 20 made of polyvinyl chloride) is provided.

The flexible container bag 10 here is, for example, a round bag having an internal capacity of 1.0 m 3. Among these, the trunk portion 11 and the bottom portion 12 constituting the bag body 13, the input portion 15, the reinforcing cloth frame 16, the suspension belt 17, and the reinforcing cloth 18 are the original material woven from the tape yarn Y shown in FIG. This is a component sheet obtained by cutting anti-A into a predetermined shape.
At the time of cutting the component sheet including the body portion 11 and the bottom portion 12, the raw fabric A made of the radiation shielding fabric S is sent to a cutting machine, where the body portion 11 and the bottom portion 12 are cut out of the raw fabric A by laser cutting or the like. Cut.
Each component sheet including the obtained body portion 11 and the bottom portion 12 uses an electric sewing machine, and the adjacent ones are sewn together, whereby the flexible container bag 10 is manufactured.

  When the bag is used, the flexible container bag 10 is transported to the site by a truck or the like. At the site, for example, contaminated topsoil contaminated with a radioactive substance (such as radioactive cesium) is scraped off by a yumbo, and this is sequentially filled into the inner bag 20 of the opened flexible container bag 10. After the filling is completed, the operator binds the opening of the inner bag 20 and further binds the input unit 15 with a binding string. Thereafter, the operator hooks each suspension rope 19 of the flexible container bag 10 on the bucket of the Yumbo, and the driver of the Yumbo rotates the arm upward to lift the flexible container bag 10 and loads it on the truck bed. Thereafter, the truck travels on the road and transports it to a predetermined storage location, where the flexible container bag 10 is lowered and stored for a predetermined period.

  Thus, as the raw fabric A, the radiation shielding fabric S obtained by weaving the tape yarn Y using the blend d of the main raw material a made of thermoplastic synthetic resin and the radiation shielding raw material b made of barium sulfate as the raw material is used. The radiation shielding raw material b kneaded into the yarn Y shields a part of the radiation contained in the contaminated topsoil. Therefore, the amount of radiation leaking out of the flexible container bag 10 from the contaminated topsoil filled in the inner bag 20 can be reduced. Further, since the warp 40 and the weft 41 of the radiation shielding fabric S are woven without gaps (FIG. 2), the tensile strength is higher than that of a fabric composed of general fibrous warps and wefts, and from the gaps. Since radiation is difficult to leak, the amount of radiation leaking out of the flexible container bag 10 can be further reduced.

Next, another radiation shielding cover according to the present invention will be described with reference to FIG.
As shown in FIG. 5, the radiation shielding cover 50 is made of the radiation shielding fabric S and covers a large number of flexible container bags 10 stored in a predetermined temporary storage place, so that the outside of the bag is covered. The amount of radiation to leak can be reduced as compared with the case of the flexible container bag 10 alone.

Next, the radiation shielding bag according to the present invention will be described with reference to FIG.
As shown in FIG. 6, the radiation shielding bag 60 is an alternative to the inner bag 20 of the flexible container bag 10 shown in FIG. 4, and the outer bag 61 obtained from the raw fabric A made of the radiation shielding fabric S. And a bag body 65 produced by sewing an inner bag 64 in which a radiation shielding metal foil layer 63 is laminated on a transparent synthetic resin base film layer 62, and an opening of the bag body 65 through a wire fastener 66. And an outer cloth 67 obtained from an original fabric A made of a radiation shielding fabric S and an inner cloth 68 in which a radiation shielding metal foil layer 63 is laminated on a transparent synthetic resin base film layer 62. And a cloth lid 69 prepared by wearing.

Thus, since the radiation shielding bag 60 is used as the inner bag 20 of the flexible container bag 10, the radiation shielding effect of the flexible container bag 10 can be further enhanced, and it is stored in the bag body 13 during use and is not exposed to sunlight. Therefore, it is not necessary to add a weathering agent to the main raw material of the tape yarn Y, and it is possible to prevent a decrease in strength of the original fabric due to the addition of the weathering agent.
The bag body 65 is a circular round shape in plan view with the entire upper surface open, and the cloth lid 69 is a circular shape in plan view having a diameter substantially the same as the opening diameter of the bag main body 65. 66 is provided over the entire upper edge of the bag body 65 and the entire outer edge of the cloth lid 69. Thus, by simply sliding the line fastener 66 along the opening edge of the bag main body 65 while ensuring the maximum opening on the upper surface of the bag main body 65 so that the filling (such as contaminated topsoil) can be easily put into the bag, The cloth lid 69 can be opened and closed easily and reliably. Moreover, the workability of opening and closing the cloth lid 69 is higher than that of fastening the inner bag using a conventional string.

  The inner bag 64 and the inner cloth 68 are made of a sheet having a three-layer structure in which one radiation shielding metal foil layer 63 made of aluminum foil is sandwiched between two transparent synthetic resin base film layers 62. . Therefore, in the inner bag 64 and the inner cloth 68, the synthetic resin base film layer 62 disposed on the inner side of the bag serves as a protective film, and, for example, the radiation shielding metal foil layer 63 comes into contact with the filler when filling the filler. It is possible to prevent the radiation shielding effect from being reduced. Moreover, the radiation shielding bag 60 of the present invention employs a configuration in which the metallic gloss surface of the radiation shielding metal foil layer 63 is exposed through the transparent synthetic resin base film layer 62 in the inner space of the bag body 65. . Therefore, even in a poor working environment where only a small amount of light can be obtained, such as in a dark place or at night, the inner surface of the bag body 65 ( Light is diffusely reflected by the fungus image glossy surface, and the entire inner surface of the bag can be illuminated by this light. As a result, the operator who moves heavy machinery (yumbo) at the site of scraping contaminated topsoil in the dark or at night makes it easier to visually recognize the opening position of the bag body 65, and the accuracy of bagging of the contaminated topsoil at night etc. Each work efficiency can be improved.

Further, the bag main body 65 includes an outer bag 61 obtained from the raw fabric A made of the radiation shielding fabric S and an inner bag in which the radiation shielding metal foil layer 63 is laminated on the transparent synthetic resin base film layer 62. 64 is sewn and has high shape retention as a bag (with a feeling of stickiness), and the radiation shielding bag 60 can be made self-supporting even without a bag self-supporting aid. Bagging can be performed.
As the tape yarn Y for raw material, for example, a main raw material a made of polypropylene and a radiation shielding raw material b made of barium sulfate are mixed in such a ratio that the main raw material a is 70% by weight and the radiation shielding raw material b is 30% by weight. Those made from the combined formulation d can be employed.
The wire fastener 66 moves the slider between a pair of left and right base tapes in which a large number of elements (service teeth) are arranged in a row, whereby the left and right elements are sequentially meshed or released, and the fastener can be freely opened and closed. This is a linear hook. As the wire fastener 66, a plastic fastener having higher weather resistance than that of a metal fastener is employed.

When the radiation shielding bag 60 is used, for example, contaminated topsoil scraped off by the yumbo is sequentially filled into the radiation shielding bag 60 in the flexible container bag 10 in which the cloth fastener 66 is removed and the cloth lid 69 is opened. After filling, the operator closes the line fastener 66, closes the opening of the radiation shielding bag 60, and further binds the input portion 15 with a binding string.
As described above, according to the radiation shielding bag 60, the bag body 65 having the radioactive substance shielding effect is provided with the cloth lid 69 having the radioactive substance shielding effect through the wire fastener 66 so as to be freely opened and closed. The amount of radioactive material radiation leaking out of the bag can be reduced. In addition, the bag body 65 employs a multi-layer structure inner bag 64 sewn to the outer bag 61, and the cloth cover 69 employs a multi-layer structure inner cloth 68 sewn to the outer cloth 67. The radiation shielding bag 60 becomes high in strength and the radiation shielding bag 60 becomes appropriately hard, so that the self-supporting property of the radiation shielding bag 60 and the self-supporting property of the flexible container bag 10 can be improved.
In addition, since the cloth lid 69 is provided at the opening of the bag body 65 via the wire fastener 66, the opening and closing operation of the opening of the bag body 65 is easy, and the sealing of the bag body 65 by the cloth lid 69 is achieved. Can be increased.

Next, in order to confirm how the increase or decrease in the amount of barium sulfate added affects the performance of barium sulfate in the radiation shielding fabric of the present invention: 1. radiation shielding test; 2. Textile strength test; A weather resistance test was performed, and the results are shown in Table 1 ( Test Examples 3 to 5, Reference Examples 1, 2, 6 to 11, and Comparative Examples 1 to 3 ). Each test method and the evaluation method of each test are as follows.

1. Radiation shielding test method At a height of 1 m from the floor, the detector is separated from the radiation source to the measurement center by 25 cm, and there is a net when there is a sample (with sample) and when there is no sample (without sample). The dose rate (removing the background dose rate) is measured 10 times, and the shielding rate is obtained from the average value of the measured values.
Radiation source: Cesium 137 Radiation source 10MBq (as of December 16, 2009)
Japan Isotope Association radiation dose rate standard gamma ray source CS454CE (source number 8101)
Measuring instrument: NaI (Tl) scintillation survey meter Aroka TCS-171B
Background dose rate = 0.04 ± 0.01 μSv / hr
Dose rate when no sample is present = 15.7 ± 0.1 μSv / hr
Shielding rate = (1−with sample / without sample) × 100
It is.
-Evaluation method of radiation shielding Since general synthetic resins of polyethylene and polypropylene do not have a radiation shielding function, the presence or absence of a shielding effect by adding barium sulfate was evaluated.

2. Test method for fabric strength and elongation test method for fabrics and knitted fabrics JIS L 1096-2010, 8.14 Tensile strength and elongation method A (strip method).
-Evaluation method of fabric strong elongation test Flexible container for non-dangerous goods It evaluated in comparison with the strong elongation required as a main body material of JISZ1651-2008.

3. Weather resistance test method Sunshine carbon arc lamp type light resistance tester and weather resistance tester JIS B 7753-2007.
-Weather resistance evaluation method Weather resistance test The residual strength ratio after 900 hours of irradiation was evaluated as 70% or more of the initial strength.

Next, Test Examples 3 to 5 (and Reference Examples 1 , 2, 6 to 11) performed and Comparative Examples 1 to 3 performed for comparison will be described.
[ Reference Example 1 ]
First, the tape yarn Y is manufactured using the tape yarn manufacturing equipment shown in FIG. That is, a main raw material a made of polypropylene in the form of pellets (polypropylene resin is a single polymer, MFR, 0.8 g / 10 min) is used, and a radiation shielding raw material b made of powdered barium sulfate is used as a main raw material a. 90 wt% and the radiation shielding raw material b is blended so as to be 10 wt% into a raw material mixer to obtain a blend d. Thereafter, the compound d is put into a T-die extruder 31, and a wide film 32 is continuously formed at a T-die temperature of 240 ° C. while kneading both raw materials a and b. Next, the film 32 is slit with a cutter 33 to obtain a large number of thick tapes 32a, which are then stretched in the warp direction on an arc-shaped hot plate 34 heated to 140 ° C., Further, the tape-like product 32b after stretching was annealed by an arc-shaped hot plate 35 at 140 ° C. to obtain a large number of tape yarns Y. Thereafter, each tape yarn Y is warped into a beam, and then the radiation shielding fabric S is woven by an automatic loom using the tape yarn Y as the warp 40 and the weft 41 (FIGS. 1 and 2).
The radiation shielding fabric S was subjected to a radiation shielding test, a fabric strength elongation test, and a weather resistance test. The results are shown in Table 1.

[ Reference Example 2 ]
Reference Example 2 is a reference example except that in the production process of tape yarn Y, the main raw material is 80% by weight and the radiation shielding raw material b is 20% by weight, which is charged into the raw material mixer to obtain the compound d. In the same manner as in Example 1, a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 3]
In Test Example 3, in the production process of the tape yarn Y, the main raw material was set to 70% by weight, the radiation shielding raw material b was set to 30% by weight and charged into the raw material mixer to obtain the compound d. Reference Example In the same manner as in Example 1 , a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 4]
In Test Example 4, in the production process of tape yarn Y, the main raw material was set to 60% by weight and the radiation shielding raw material b was set to 40% by weight into the raw material mixer to obtain the compound d. Reference Example In the same manner as in Example 1 , a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Test Example 5]
In Test Example 5, in the production process of the tape yarn Y, the main raw material was 50% by weight and the radiation shielding raw material b was 50% by weight, which was charged into the raw material mixer to obtain the compound d. Reference Example In the same manner as in Example 1 , a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[ Reference Example 6 ]
In Reference Example 6, in the manufacturing process of the tape yarn Y, except that the main raw material was 40% by weight, the radiation shielding material b was charged into a raw material mixing machine as 60 wt% so as to obtain a formulation d are reference examples In the same manner as in Example 1 , a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[ Reference Example 7 ]
In Reference Example 7 , in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, a product (compound) in which these raw materials a and b are mixed, A test piece of radiation shielding fabric S was obtained in the same manner as in Reference Example 1 , except that the weathering agent c was 0.2% by weight and was added to the raw material mixer to obtain the blend d. The results are shown in Table 1.

[ Reference Example 8 ]
In Reference Example 8 , in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, a mixture (mixture) of these raw materials a and b was used. A test piece of radiation shielding fabric S was obtained in the same manner as in Reference Example 1 , except that 0.4% by weight of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[ Reference Example 9 ]
In Reference Example 9 , in the manufacturing process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, a mixture (mixture) of these raw materials a and b was used. A test piece of the radiation shielding fabric S was obtained in the same manner as in Reference Example 1, except that 0.6 wt% of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[ Reference Example 10]
In Reference Example 10 , in the manufacturing process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, a mixture (mixture) of these raw materials a and b was used. A test piece of the radiation shielding fabric S was obtained in the same manner as in Reference Example 1 except that 1.0% by weight of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[ Reference Example 11]
In Reference Example 11 , in the production process of the tape yarn Y, in addition to the main raw material a being 70% by weight and the radiation shielding raw material b being 30% by weight, a mixture (mixture) of these raw materials a and b was used. A test piece of radiation shielding fabric S was obtained in the same manner as in Reference Example 1 except that 2.0% by weight of the weathering agent c was added to the raw material mixer to obtain the compound d. The results are shown in Table 1.

[Comparative Example 1]
In Comparative Example 1, a test piece of radiation shielding fabric S was prepared in the same manner as in Reference Example 1 except that only the main raw material a was introduced into the raw material mixer in the production process of the tape yarn Y to obtain the compound d. Got. The results are shown in Table 1.

[Comparative Example 2]
In Comparative Example 2, in the production process of the tape yarn Y, the main raw material was set to 95% by weight, the radiation shielding raw material b was set to 5% by weight and charged into the raw material mixer to obtain the compound d. Reference Example In the same manner as in Example 1 , a test piece of radiation shielding fabric S was obtained. The results are shown in Table 1.

[Comparative Example 3]
In Comparative Example 3, in the production process of the tape yarn Y, the main raw material was set to 30% by weight and the radiation shielding raw material b was set to 70% by weight, but the film was not formed. The results are shown in Table 1.

As can be seen from Table 1, the radiation shielding effect increased as the amount of barium sulfate added in the blend (raw material k) d increased, but the fabric strength and elongation decreased. However, when the addition amount of barium sulfate was 10 to 80% by weight, both the radiation shielding effect and the fabric strong elongation were evaluated as raw materials for the flexible container bag 10. In particular, when the addition amount of barium sulfate is 30 to 50% by weight, for example, when the radiation shielding fabric S is used as the raw fabric A for the flexible container bag 10, a suitable radiation shielding effect and fabric strength are obtained. Obtained.
As for the weather resistance, good results are obtained when the amount of the weathering agent in the formulation d is 0.2 to 2.0% by weight, particularly when the amount is 0.6 to 2.0% by weight. Optimum weather resistance was obtained.

  The present invention is useful, for example, as a technique for storing and transporting contaminated topsoil contaminated with radioactive substances.

10 Radiation shielding flexible container bag,
50 radiation shielding cover,
60 radiation shielding bags,
61 Outer bag,
62 synthetic resin base film layer,
63 radiation shielding metal foil layer,
64 inner bag,
65 bag body,
66 line fastener,
67 Outer cloth,
68 Inner cloth,
69 cloth lids,
S radiation shielding fabric,
Y tape yarn,
a Main raw material (thermoplastic synthetic resin),
b Radiation shielding material (barium sulfate),
c Additives (weatherproofing agents),
d Formulation (raw material for kneading).

Claims (6)

  A radiation-shielding woven fabric woven from a tape yarn having a strength of 3.0 cN / dt or more and made using a kneading raw material of 20 to 90% by weight of a thermoplastic synthetic resin and 10 to 80% by weight of barium sulfate.   The radiation shielding fabric according to claim 1, wherein the content of the barium sulfate in the kneading raw material is 30 to 50% by weight.   The at least one additive selected from a light stabilizer and an ultraviolet absorber is added to the kneading material in an amount of 0.1 to 2.0% by weight based on 100% by weight of the kneading material. Or the radiation shielding textiles of Claim 2. A radiation shielding flexible container bag having a plurality of component sheets obtained by cutting an original fabric, and sewing the adjacent ones among the plurality of component sheets,
The radiation shielding flexible container bag which the said original fabric consists of a radiation shielding textile fabric in any one of Claims 1-3.   A radiation shielding cover made of a radiation shielding fabric according to any one of claims 1 to 3, wherein the sheet material covers a radioactive substance storage body. An outer bag obtained from the original fabric,
A bag body produced by sewing an inner bag in which a radiation shielding metal foil layer is laminated on a synthetic resin base film layer;
An outer cloth provided at the opening of the bag body through a wire fastener and obtained from the original fabric;
A radiation shielding bag comprising a cloth lid made by sewing an inner cloth in which the radiation shielding metal foil layer is laminated on the synthetic resin base film layer,
The radiation shielding bag which the said original fabric consists of the radiation shielding textiles in any one of Claims 1-3.

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