Hydrogen generating molded body

Abstract

To provide a hydrogen generating molded article in which the occurrence or growth of cracks is effectively suppressed.SOLUTION: A hydrogen generating molded article that generates hydrogen by coming into contact with water, wherein (1) the hydrogen generating molded article includes a first resin-containing layer, a second resin-containing layer, and a third resin-containing layer that are sequentially stacked, and (2) the second resin-containing layer includes 1 to 15% by weight of hydrogen generating particles capable of generating hydrogen by coming into contact with moisture, (3) The first resin-containing layer and the third resin-containing layer contain 0% by weight or more and less than 3% by weight of hydrogen generating particles capable of generating hydrogen by contact with moisture, (4) a total thickness of the first resin-containing layer, the second resin-containing layer, and the third resin-containing layer is 25 to 30 μ m, and (5) a thickness of the second resin-containing layer is 5 to 8 μm.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a molded body that generates hydrogen, and more particularly to a molded body that generates hydrogen when it comes into contact with moisture or a substance containing moisture. [Background technology]

[0002] In recent years, it has become clear that when hydrogen gas, water, or liquid containing hydrogen is applied to the human body, beneficial effects are obtained. For this reason, materials that can generate hydrogen or materials that contain hydrogen have been proposed.

[0003] For example, a container with a hydrogen generating function has been proposed, which includes a hydrogen generating layer containing a particulate hydrogen generating agent for supplying hydrogen to a liquid substance contained inside the container (Patent Document 1).

[0004] Also disclosed is a hydrogen generating molded article (Patent Document 2) made of a resin composition containing hydrogen generating particles that generate molecular hydrogen upon contact with moisture. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-104455 [Patent Document 2] Japanese Patent Application Laid-Open No. 2019-182699 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in these conventional materials, a gas layer is formed by a small amount of molecular hydrogen generated by the reaction of moisture in the atmosphere with the hydrogen generating particles, which may cause cracks to form on the surface.

[0007] If the cracks thus generated grow, the molecular hydrogen generated from the hydrogen generating molded body will easily escape, making it impossible to enjoy its hydrogen generating ability. Not only that, if the sheet-shaped hydrogen generating molded body is used as a packaging material, for example, the packaging material itself may become more prone to tearing, and contents other than hydrogen may leak out.

[0008] Therefore, a primary object of the present invention is to provide a hydrogen generating molded article in which the occurrence or growth of cracks is effectively suppressed. [Means for solving the problem]

[0009] The present inventors have conducted extensive research in light of the problems of the prior art and have found that the above-mentioned object can be achieved by a hydrogen generating molded body having a specific configuration, thereby completing the present invention.

[0010] That is, the present invention relates to the following hydrogen generating molded article and method for producing the same. 1. A hydrogen generating molded body that generates hydrogen upon contact with water, (1) The hydrogen generating molded article includes a first resin-containing layer, a second resin-containing layer, and a third resin-containing layer laminated in this order, (2) The second resin-containing layer contains 1 to 15 wt % of hydrogen generating particles capable of generating hydrogen upon contact with moisture, (3) The first resin-containing layer and the third resin-containing layer contain hydrogen generating particles capable of generating hydrogen upon contact with moisture in an amount of 0% by weight or more and less than 3% by weight, (4) The total thickness of the first resin-containing layer, the second resin-containing layer, and the third resin-containing layer is 25 to 30 μm, (5) The thickness of the second resin-containing layer is 5 to 8 μm. A hydrogen generating molded body characterized by: 2. The hydrogen generating molded article according to item 1, wherein the hydrogen generating particles contain at least one selected from the group consisting of metal hydride particles, metal elements, and alloys containing these elements. 3. The hydrogen generating molded article according to item 1, wherein the hydrogen generating particles have a volume average particle size of 1 to 100 μm. 4. The hydrogen generating molded article according to item 1, wherein the hydrogen generating particles contain magnesium hydride. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a hydrogen generating molded article in which the occurrence or growth of cracks is effectively suppressed.

[0012] In particular, the hydrogen generating molded body of the present invention has a multi-layer structure in which each layer is controlled to a specific thickness, and further, the layer containing the hydrogen generating particles is sandwiched between other layers, so that the hydrogen generating particles in the hydrogen generating molded body are less likely to react with moisture in the atmosphere. This suppresses the formation of new gas layers that may be generated by the reaction, and also suppresses the growth of fine gas layers that already exist. As a result, even if moisture in the atmosphere reacts with some of the hydrogen generating particles, cracks are less likely to occur on the surface. This effectively suppresses or prevents the phenomenon of molecular hydrogen permeating through cracks. On the other hand, moisture slowly penetrates over time, allowing the hydrogen generating particles to come into contact with moisture at the desired time, generating molecular hydrogen.

[0013] In particular, when the hydrogen generating molded article of the present invention is manufactured by the manufacturing method described below, the materials constituting each layer are laminated in a molten state and substantially without stretching, so that the formation of voids around the hydrogen generating particles due to stretching can be avoided. If such voids are formed, the hydrogen generating particles become more susceptible to reaction with moisture in the atmosphere (especially in the voids) even during the manufacturing process, causing the voids to grow and ultimately cause cracks. In this regard, the manufacturing method of the present invention can also suppress the formation of voids that could serve as the starting point for cracks, as described above, so that the occurrence of cracks can be more effectively suppressed or prevented.

[0014] Such a hydrogen generating molded article can be used by itself as a hydrogen supply material, and can also be suitably used as a component of an article that requires hydrogen supply (for example, packaging material, container, etc.). [Brief explanation of the drawings]

[0015] [Figure 1] 1 is an image diagram of a cross-sectional example of a hydrogen generating molded body according to a preferred embodiment of the present invention. [Figure 2] The photographs of the appearance of the hydrogen generating molded body when no cracks have occurred (FIG. 2A) and when cracks have occurred (FIGS. 2B and 2C) are shown, respectively. DETAILED DESCRIPTION OF THE INVENTION

[0016] 1. Hydrogen generating compact The hydrogen generating molded article of the present invention (molded article of the present invention) is a hydrogen generating molded article that generates hydrogen upon contact with water, (1) The hydrogen generating molded article includes a first resin-containing layer, a second resin-containing layer, and a third resin-containing layer laminated in this order, (2) The second resin-containing layer contains 1 to 15 wt % of hydrogen generating particles capable of generating hydrogen upon contact with moisture, (3) The first resin-containing layer and the third resin-containing layer contain hydrogen generating particles capable of generating hydrogen upon contact with moisture in an amount of 0% by weight or more and less than 3% by weight, (4) The total thickness of the first resin-containing layer, the second resin-containing layer, and the third resin-containing layer is 25 to 30 μm, (5) The thickness of the second resin-containing layer is 5 to 8 μm. It is characterized by:

[0017] An image of the layer structure of the molded product of the present invention is shown in Figure 1. As shown in Figure 1, the molded product of the present invention 1 has a first resin-containing layer 10, a second resin-containing layer 20, and a third resin-containing layer 30 laminated in this order, with hydrogen-generating particles 22 dispersed in the second resin-containing layer 20. As shown in Figure 1, the molded product of the present invention can be in the form of a sheet (laminate), which makes it suitable for use as a packaging material, etc. In the molded product of the present invention 1 of Figure 1, the first resin-containing layer 10 and the second resin-containing layer 20 are laminated so as to be in direct contact with each other, and the second resin-containing layer 20 and the third resin-containing layer 30 are laminated so as to be in direct contact with each other.

[0018] In this case, at least one of the first resin-containing layer and the third resin-containing layer is preferably the outermost layer, but other layers may be laminated thereon. The outermost layer can effectively supply hydrogen to an object (e.g., food) to which hydrogen is to be supplied by being in direct contact with the object.

[0019] Generally, when a hydrogen generating molded body is manufactured in the atmosphere, the resin and hydrogen generating particles are kneaded and molded. This can cause moisture in the atmosphere to react with the hydrogen generating particles, generating gaseous molecular hydrogen on the surface of the hydrogen generating particles, forming a fine gas layer. Because the molecular hydrogen in this gas layer is a low-molecular-weight compound, it quickly escapes from the molded body over time, and air from the atmosphere flows into the gas layer. When the hydrogen generating molded body is completed in this state, it is thought that the hydrogen generating molded body will have fine gas layers (pores) near the surface of the multiple hydrogen generating particles. After completion, when the hydrogen generating particles react with moisture in the atmosphere, the fine gas layers grow, and cracks originating from these gas layers appear, reducing the strength or hydrogen generating capacity of the hydrogen generating molded body. That is, when stress, such as bending, is applied to the hydrogen generating molded body, cracks begin to form at the edges of the gas layers present at the interface between the resin matrix and the multiple hydrogen generating particles, ultimately causing cracks in the hydrogen generating molded body and ultimately reducing the hydrogen generating capacity.

[0020] In contrast, as described above, in the molded product 1 of the present invention, the second resin-containing layer 20 containing the hydrogen generating particles 22 is protected by the first resin-containing layer 10 and the third resin-containing layer 30, making it difficult for moisture in the air to permeate. Therefore, even if fine gas layers are present in the hydrogen generating molded product, further growth can be suppressed, making it difficult for reaction between moisture in the air and the hydrogen generating particles to occur. At the same time, the layer structure described above can also suppress the formation of new gas layers. As a result, the molded product of the present invention can suppress the occurrence of cracks, or even if fine gas layers are present, further crack growth can be suppressed. This makes it possible to provide a hydrogen generating product with excellent durability, hydrogen generating ability, etc.

[0021] In particular, in the present invention, by setting the total thickness A (FIG. 1) of the first resin-containing layer 10, the second resin-containing layer 20, and the third resin-containing layer 30 to 25 to 30 μm and the thickness B (FIG. 2) of the second resin-containing layer 20 to 5 to 8 μm, the molded product of the present invention is further less likely to develop cracks on the surface (FIG. 2A). In this way, it is possible to prevent cracks from developing on the surface of the molded product, and it is possible to provide a hydrogen generating molded product with excellent durability.

[0022] (1) Second resin-containing layer The matrix (base material) constituting the second resin-containing layer of the molded body of the present invention functions as a support for fixing the hydrogen generating particles, and also has the function of supplying water molecules to the hydrogen generating particles and allowing molecular hydrogen emitted from the hydrogen generating particles to pass through.

[0023] The second resin-containing layer contains a resin and hydrogen generating particles, and the resin primarily functions as a matrix to support the hydrogen generating particles dispersed therein. Therefore, the type of resin is not particularly limited as long as it fulfills this role. For example, in addition to polyolefin resins such as low-density polyethylene, high-density polyethylene, linear low-density polyethylene, and polypropylene, at least one of synthetic resins such as styrene resin, vinyl chloride resin, polyester resin (polyethylene terephthalate, polybutylene terephthalate, etc.), polyamide resin, urethane resin, fluororesin, modified fluororesin, epoxy resin, polyethylene glycol, ethylene-vinyl alcohol copolymer resin, and polyethylene oxide can be used. In particular, in the present invention, polyolefin resins are preferred from the viewpoint of crack suppression effect, and polypropylene is particularly preferred.

[0024] The content of the resin in the second resin-containing layer is not limited, but is usually about 80 to 95% by weight, and preferably 85 to 90% by weight.

[0025] The hydrogen generating particles may be any particles that generate hydrogen upon contact with moisture. In this case, the moisture may be liquid water, a composition (solid) containing water, or water vapor, and upon contact with the moisture, the particles react to generate hydrogen (molecular hydrogen, including hydrogen gas).

[0026] Such hydrogen generating particles are preferably particles containing one or more metals selected from the group consisting of metal hydride particles such as magnesium hydride, calcium hydride, barium hydride, beryllium hydride, strontium hydride, lithium hydride, sodium hydride, sodium borohydride, lithium sodium hydride, silicon hydride, etc., and simple metals such as magnesium and aluminum, and alloys containing these metals. Among these, magnesium hydride is preferred.

[0027] The size of the hydrogen generating particles is not particularly limited, but preferably has a volume average particle diameter of about 1 to 100 μm. Therefore, it can be set to, for example, 10 to 50 μm. If the volume average particle diameter is less than 1 μm, the hydrogen generating particles tend to aggregate, which may result in poor dispersibility in the resin. If the volume average particle diameter exceeds 100 μm, the weight of the hydrogen generating particles may result in poor dispersibility in the resin.

[0028] In particular, in the present invention, the volume average particle diameter may be equal to or larger than the thickness of the second resin-containing layer. That is, the present invention also encompasses cases where the volume average particle diameter D of the hydrogen generating particles and the thickness t of the second resin-containing layer satisfy the relationship D≧t. Therefore, for example, it is possible to set 3t≧D≧1.5t. Even when the hydrogen generating particles are large, the hydrogen generating particles protruding from the second resin-containing layer are covered by the first resin-containing layer or the third resin-containing layer, and therefore can be prevented from rapidly reacting with moisture in the atmosphere. On the other hand, since the hydrogen generating particles are close to the outermost surface of the first resin-containing layer or the second resin-containing layer, when the molded article of the present invention comes into contact with water, the desired hydrogen generating capacity can be more reliably obtained while more effectively suppressing the occurrence of cracks.

[0029] In the present invention, the volume average particle size of the hydrogen generating particles is the value of the average particle size D50 (50% particle size) calculated from the result of the volume cumulative particle size distribution of the hydrogen generating particles measured by laser diffraction method.

[0030] The content of the hydrogen generating particles in the second resin-containing layer is not limited, but is usually about 1 to 15 wt %, and preferably 3 to 15 wt %. By setting the content within this range, a sufficient amount of hydrogen can be generated and the occurrence of cracks can be more effectively suppressed.

[0031] The second resin-containing layer may contain other components within the range that does not impair the effects of the present invention. Examples of other components include colorants, plasticizers, antioxidants, etc. The total content of these components may be, for example, 5% by weight or less in each layer, but is not limited to this.

[0032] (2) First Resin-Containing Layer and Third Resin-Containing Layer The first resin-containing layer and the third resin-containing layer are layers for suppressing the reaction of the hydrogen generating particles in the second resin-containing layer with moisture in the air, particularly during and after the production of the molded article of the present invention.

[0033] The resin contained in the first resin-containing layer and the third resin-containing layer is not particularly limited, and examples thereof include polyolefin resins such as low-density polyethylene, high-density polyethylene, linear low-density polyethylene, and polypropylene, as well as at least one synthetic resin such as styrene resin, vinyl chloride resin, polyester resin (polyethylene terephthalate, polybutylene terephthalate, etc.), polyamide resin, urethane resin, fluororesin, modified fluororesin, epoxy resin, polyethylene glycol, ethylene-vinyl alcohol copolymer resin, and polyethylene oxide.

[0034] In the present invention, among these resins, it is preferable to use at least one of polyolefin resin (particularly polypropylene) and ethylene-vinyl alcohol copolymer resin from the viewpoint of crack suppression effect, etc. Furthermore, it is preferable to employ a polyolefin resin (particularly polypropylene) for the layer of the first resin-containing layer and the third resin-containing layer that is closer to the target to which hydrogen is supplied.

[0035] In the present invention, the types of resins contained in the first resin-containing layer and the third resin-containing layer may be the same or different.

[0036] The resin contents in the first resin-containing layer and the third resin-containing layer are not particularly limited, but are usually 90 to 100% by weight, and preferably 95 to 100% by weight. In this case, the resin contents in the first resin-containing layer and the third resin-containing layer may be the same or different from each other.

[0037] The first resin-containing layer and the third resin-containing layer may contain other components as long as they do not impair the effects of the present invention. Examples of other components include colorants, plasticizers, antioxidants, etc. The total content of these components in each layer may be, for example, 5% by weight or less, but is not limited to this.

[0038] The first resin-containing layer and the third resin-containing layer may contain hydrogen generating particles in a range of 0% by weight or more and less than 3% by weight. Therefore, for example, the content can be set to 0% by weight or more and 2% by weight or less, or, for example, 0% by weight or more and 1% by weight or less. In the present invention, the layer that generates hydrogen is particularly the second resin-containing layer. Therefore, the first resin-containing layer and the third resin-containing layer do not need to contain hydrogen generating particles, but a small amount is allowed within a range that does not impair the effects of the present invention. In particular, the content of hydrogen generating particles in the first resin-containing layer and the third resin-containing layer is preferably 0% by weight.

[0039] The thicknesses of the first resin-containing layer and the third resin-containing layer are not particularly limited as long as the total thickness A of the first resin-containing layer, the second resin-containing layer, and the third resin-containing layer is 25 to 30 μm and the thickness B of the second resin-containing layer is in the range of 5 to 8 μm, as shown in FIG. 1 .

[0040] In particular, the thicknesses of the first resin-containing layer and the third resin-containing layer are preferably each in the range of 5 to 20 μm. For example, if the thickness of the first resin-containing layer is 5 μm, the thickness of the third resin-containing layer may be set in the range of 12 to 20 μm, depending on the thickness of the second resin-containing layer 20 (5 to 8 μm). Also, for example, if the thickness of the first resin-containing layer is 10 μm, the thickness of the third resin-containing layer may be set in the range of 7 to 15 μm, depending on the thickness B of the second resin-containing layer (5 to 8 μm).

[0041] The first resin-containing layer and the third resin-containing layer may have the same thickness or different thicknesses, as long as the total thickness A of the first resin-containing layer, the second resin-containing layer, and the third resin-containing layer is 25 to 30 μm and the thickness B of the second resin-containing layer is within the range of 5 to 8 μm.

[0042] (4) Shape and usage of the hydrogen generating molded body The shape of the hydrogen generating molded article can be appropriately set depending on its application, etc. A typical example is a sheet (film) shape, but is not limited to this. When the final product is in the form of a bottle, tray, cup, dish, bag, etc., the shape can be appropriately set depending on the shape. In these cases, a shape can be preferably adopted in which the first resin-containing layer or the third resin-containing layer can be in direct contact with the surface that contacts the object that supplies hydrogen.

[0043] Furthermore, the size of these is not particularly limited as long as the desired amount of hydrogen generation is obtained. When the molded product of the present invention is in the form of a sheet, it is preferable that the thickness is about 1 to 200 μm, particularly from the viewpoint of strength or hydrogen generation quality.

[0044] In the present invention, two or more molded articles of the present invention can be used in combination. In this case, the type and content of the resin component, the type and content of the hydrogen-generating particles, etc., of the two or more molded articles of the present invention can be the same or different from each other. For example, a laminate can be used in which a sheet-shaped molded article a of the present invention is laminated with a sheet-shaped molded article b of the present invention, the type of the resin component and the type of the hydrogen-generating particles of which are different from those of the molded article a. The laminate can be either two-layered or three or more layers.

[0045] In addition, the molded article of the present invention can be used in combination with other materials (substrates). The other materials are not particularly limited and may be, for example, metals (including alloys), ceramics, polymeric materials (resins, rubbers, etc.), glass, wood, stone, etc. Furthermore, flat materials include at least one of paper, metal cans, metal plates, metal foils, metal-deposited films, nonwoven fabrics, cloths, and resin sheets. Therefore, for example, a laminate can be used in which another layer (metal foil, etc.) is laminated on the surface of the sheet-like molded article a of the present invention and its first resin-containing layer or third resin-containing layer. The laminate can be either two-layered or three or more layers.

[0046] The molded article of the present invention can generate hydrogen (hydrogen gas) when the hydrogen generating particles in the second resin-containing layer come into contact with moisture, and can therefore be used as a hydrogen supply source for an object to which hydrogen is to be supplied (hydrogen supply destination).

[0047] The hydrogen supply destination may be in direct or indirect contact with the molded article of the present invention. Examples of hydrogen supply destinations include (a) foodstuffs such as beverages, meat, seafood, vegetables, and fruits, (b) processed foods made from such foodstuffs, (c) plants such as fresh flowers, fungi, bacteria, and seeds, and (d) others (blood for transfusion, infusions, bath water, laundry water, detergent, air, wound dressings, cosmetics, diapers, pet drinks, aquarium water, microorganisms, soil, feed, indoor spaces, the human body, and animals). These can be hydrogen supply destinations and also water sources for the hydrogen generating molded article, but the water source may be different from the hydrogen supply destination.

[0048] In the molded product of the present invention, it is particularly preferable that the hydrogen supply destination also serves as a moisture supply source for the hydrogen generating molded product. For example, when the molded product of the present invention (a bag made of a sheet-like molded product) is used as a packaging material for hydrogen water and hydrogen water is sealed in the bag, hydrogen is supplied from the molded product of the present invention to the hydrogen water, and the hydrogen water serves as a moisture supply source that supplies moisture to the molded product of the present invention (hydrogen supply source).

[0049] 2. Manufacturing method of hydrogen generating molded body One embodiment for producing a hydrogen generating molded article of the present invention will be described in detail below. Note that the following production method is merely one embodiment of the production method of the present invention, and is not intended to be limiting.

[0050] The hydrogen generating molded body can be suitably manufactured by a manufacturing method including, for example, (1) a step of compounding raw materials containing hydrogen generating particles and resin (compounding step), (2) a drying step of drying the obtained compound, and (3) a step of sandwiching the dried compound on both sides with raw materials containing resin but not hydrogen generating particles, and molding the compound while melting.

[0051] In the production method of the present invention, the above series of steps can all be carried out in the atmosphere, but they can also be carried out in an environment that is shielded from the atmosphere (especially moisture).

[0052] Compounding process In the compounding step, a raw material (first raw material) containing hydrogen generating particles and a resin is compounded. As a result, the hydrogen generating particles are dispersed in a matrix containing the resin. The form of the compound is not particularly limited, and it is usually granular (pellet-like). The compounding method is not particularly limited, and for example, a method of dissolving and kneading the raw material can be suitably used.

[0053] Drying process In the drying step, the obtained compound is dried. This allows the moisture adsorbed in the compound to be removed. The drying method is not limited as long as it can remove the predetermined amount of moisture, but at least one of dehumidification drying, hot air drying, nitrogen drying, vacuum drying, etc. can be preferably used, as it can substantially eliminate the voids in the molded product of the present invention.

[0054] The degree of drying is not particularly limited, but it is generally preferable that the water content of the compound be about 200 ppm by weight or less, and more preferably about 100 ppm by weight or less. By removing the water adsorbed in the compound in this way, the phenomenon of molecular hydrogen generation during the production of the hydrogen generating molded article can be more effectively suppressed.

[0055] Molding process In the molding process, the dried compound is sandwiched between two raw materials (second raw materials) containing resin but not containing hydrogen generating particles, and molded while melting. That is, the molten compound (first raw material) containing hydrogen generating particles is molded by sandwiching it between two molten materials of the second raw material. This allows for the production of a molded product with a "layer made of the second raw material / layer made of the first raw material / layer made of the second raw material" structure. In this way, it is possible to obtain a molded hydrogen generating product with a shape suited to the application while suppressing or preventing the formation of voids around the hydrogen generating particles.

[0056] The molding method may be a method in which the first raw material and the second raw material are molded in a molten state, and melt molding without stretching is particularly preferred. Molding in a molten state allows a laminate to be obtained in a substantially unstretched state, thereby suppressing or preventing the occurrence of voids around the hydrogen generating particles during production. As a result, a molded product in which crack generation is more effectively suppressed can be obtained. Specifically, any method, such as extrusion molding, injection molding, blow molding, or press molding, can be used. In particular, in the present invention, it is preferable to employ three-layer co-extrusion molding among extrusion molding methods, since it can more reliably obtain a molded product consisting of three layers as described above. Molding in a molten state allows a laminate to be obtained in a substantially unstretched state, thereby suppressing or preventing the occurrence of voids around the hydrogen generating particles during production. As a result, a molded product in which crack generation is more effectively suppressed can be obtained.

[0057] The melting temperature should be a temperature sufficient to laminate and form a film without stretching, and can be set appropriately depending on the type of resin raw material used, etc., but it is desirable to set the temperature to a temperature higher than the melting point of the resin with the highest melting point among the resins contained in the compound and the resins in the second raw material.

[0058] The shape of the molded product is not particularly limited, and may be any of a sheet or film shape, a bottle, a tray, a cup, a plate, a bag, and the like.

[0059] The obtained molded product is preferably stored in a state where it is prevented from coming into contact with moisture until it is used. For example, it may be stored under vacuum or in a sealed state in the presence of a desiccant.

[0060] Furthermore, the molded body obtained as described above is substantially in an unstretched state, and voids resulting from the hydrogen generating particles are absent or extremely few. That is, a structure can be obtained in which voids (particularly voids that may be formed by stretching) are substantially absent around the hydrogen generating particles. If this is stretched, there is a risk that new voids will be formed around the hydrogen generating particles or that minute voids will expand to an extent that will have an adverse effect. Therefore, it is desirable that the manufacturing method of the present invention does not include a stretching step. [Example]

[0061] The features of the present invention will be described in more detail below with reference to examples and comparative examples, but the scope of the present invention is not limited to these examples.

[0062] [Example 1] A commercially available magnesium hydride powder (Wako Pure Chemical Industries, Ltd., volume average particle size D50: 15 μm) was kneaded into a colorless, transparent polypropylene resin as a matrix to prepare a magnesium hydride-containing compound. The ratio was 6 parts by weight of magnesium hydride powder per 100 parts by weight of polypropylene resin. The magnesium hydride-containing compound was dried in a hot air dryer at 80°C for 3 hours. The moisture content of the dried magnesium hydride-containing compound was measured using a Karl Fischer moisture meter (Kyoto Electronics Manufacturing Co., Ltd.) under a nitrogen gas atmosphere, and was found to be less than 200 ppm (below the measurement limit). Next, a commercially available colorless and transparent polypropylene resin and a magnesium hydride-containing compound were melt-extruded to form a three-layer film consisting of a 10 μm-thick surface layer (A), a 7 μm-thick magnesium hydride-containing layer (B), and a 10 μm-thick food contact layer (C). The surface layer (A) and food contact layer (C) were made of a commercially available colorless and transparent polypropylene resin, and the magnesium hydride-containing compound was used for the magnesium hydride-containing layer (B).

[0063] [Example 2] A film was produced in the same manner as in Example 1, except that the magnesium hydride powder content in the magnesium hydride-containing layer (B) was 3 wt %, an ethylene-vinyl alcohol copolymer resin was used for the surface layer (A), and each layer was a 5 μm-thick surface layer (A), a 5 μm-thick magnesium hydride-containing layer (B), and a 15 μm-thick food contact layer (C).

[0064] [Example 3] A film was produced in the same manner as in Example 1, except that the magnesium hydride powder content of the magnesium hydride-containing layer (B) was 15 wt % and the thickness was 8 μm, and the thicknesses of the surface layer (A) and food contact layer (C) were each 11 μm.

[0065] [Comparative Example 1] A film was produced in the same manner as in Example 1, except that the thickness of the magnesium hydride-containing layer (B) was 10 μm.

[0066] Comparative Example 2 A film was produced in the same manner as in Example 1, except that the thickness of the surface layer (A) and the food contact layer (C) was 7 μm.

[0067] Comparative Example 3 A film was produced in the same manner as in Example 1, except that the thicknesses of the surface layer (A), the magnesium hydride-containing layer (B), and the food contact layer (C) were each 20 μm.

[0068] Comparative Example 4 A film was produced in the same manner as in Example 2, except that the thickness of the magnesium hydride-containing layer (B) was 10 μm.

[0069] Comparative Example 5 A film was produced in the same manner as in Example 2, except that the thickness of the magnesium hydride-containing layer (B) was 9 μm and the thickness of the food contact layer (C) was 20 μm.

[0070] Comparative Example 6 A film was produced in the same manner as in Example 3, except that the content of magnesium hydride powder was 18 wt %.

[0071] Comparative Example 7 A film was produced in the same manner as in Example 1, except that the content of magnesium hydride powder in the magnesium hydride-containing layer (B) was 1 wt % and the thickness was 4 μm.

[0072] [Test Example 1] The films obtained in each of the Examples and Comparative Examples were examined for the presence or absence of voids, appearance, and strength according to the following methods. The results are shown in Table 1.

[0073] (1) Appearance The appearance of the obtained film was evaluated visually, and those with bubbles or holes due to bubbles were marked "X", and those without bubbles or holes were marked "O". Table 1 shows examples of the appearance of films with no bubbles or holes (Fig. 2A), with bubbles (Fig. 2B), and with holes (Fig. 2C).

[0074] (2) Strength Each film was cut into a size of 1.5 cm x 10 cm, and then each end was grasped with a finger and pulled strongly in the longitudinal direction. Films that were torn by the force of human fingers were marked "X", films that did not tear but cracked (partial breakage) were marked "△", and films that did not tear or crack were marked "O".

[0075] [Table 1]

[0076] As is clear from the results in Table 1, the hydrogen generating molded body of the present invention suppresses cracks that occur due to the reaction between moisture in the atmosphere and the particulate hydrogen generating agent (hydrogen generating particles) dispersed in the resin matrix, and can therefore achieve relatively high strength.

Claims

1. A hydrogen generating molded body that generates hydrogen upon contact with water, (1) The hydrogen generating molded article includes a first resin-containing layer, a second resin-containing layer, and a third resin-containing layer laminated in this order, (2) The second resin-containing layer contains 1 to 15 wt % of hydrogen generating particles capable of generating hydrogen upon contact with moisture, (3) The first resin-containing layer and the third resin-containing layer contain hydrogen generating particles capable of generating hydrogen upon contact with moisture in an amount of 0% by weight or more and less than 3% by weight, (4) The total thickness of the first resin-containing layer, the second resin-containing layer, and the third resin-containing layer is 25 to 30 μm, (5) The thickness of the second resin-containing layer is 5 to 8 μm. A hydrogen generating molded body characterized by:

2. 2. The hydrogen generating molded article according to claim 1, wherein the hydrogen generating particles contain at least one selected from the group consisting of metal hydride particles, simple metals, and alloys containing these.

3. 2. The hydrogen generating molded article according to claim 1, wherein the hydrogen generating particles have a volume average particle size of 1 to 100 μm.

4. The hydrogen generating molded article according to claim 1 , wherein the hydrogen generating particles contain magnesium hydride.

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