Molding composition manufacturing method, molded body manufacturing method, molding material, and molded body

Abstract

According to an embodiment, the present invention provides a molding composition manufacturing method including: a step for obtaining a raw material composition containing inorganic solid materials and an organic material that is liquidized by being heated, to glue the inorganic solid materials together; a step for heating the raw material composition in a material space; and a step for extruding the heated raw material composition, as a molding composition, from the material space.

Description

Method for producing molding composition, method for producing molded body, molding material, and molded body

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 309,019, filed February 11, 2022, the contents of which are incorporated herein by reference.

[0002] Known molding techniques for producing molded articles having a desired shape include injection molding, extrusion molding, and blow molding. These techniques are widely used as simple methods for achieving a desired shape (see, for example, Patent Document 1). In these methods, a thermoplastic resin material in a fluidized state at high temperature is extruded into a mold having a predetermined shape, and a predetermined molding process is carried out to impart the corresponding shape to the resin material.

[0003] Japanese Patent Application Publication No. 11-240051

[0004] On the other hand, the above molding methods are not suitable for producing molded bodies containing inorganic materials. This is because, in general, many inorganic materials do not fluidize at the heating temperatures used in the above molding techniques, and molded bodies made by solidifying inorganic material powders tend to be brittle. For this reason, it is not easy to use molding techniques such as injection molding and extrusion molding to mold inorganic materials.

[0005] The problem to be solved by the present invention is to provide a method for producing a molding composition, a method for producing a molded body, a molding material, and a molded body, which can easily produce a molded body from a raw material composition containing an inorganic material.

[0006] The present invention may include the following aspects. [1] A method for producing a molding composition, comprising the steps of obtaining a raw material composition containing inorganic solid materials and an organic material that is fluidized by heating and bonds the inorganic solid materials together, heating the raw material composition in a material space, and extruding the heated raw material composition from the material space as the molding composition. [2] The method according to [1], wherein the organic material is a plant material. [3] The method according to [1] or [2], wherein the organic material includes one or more selected from the group consisting of lignin, cellulose, hemicellulose, and sugar. [4] The method according to any one of [1] to [3], wherein the inorganic solid material includes one or more selected from the group consisting of one or more types of concrete, one or more types of cement, one or more types of minerals, one or more types of metals, one or more types of ceramics, one or more types of glass, one or more types of slag, one or more types of lime, one or more types of incineration ash, and composite materials thereof. [5] The method according to any one of [1] to [3], wherein the mass m of the organic material is １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２ is greater than 1. [6] The method according to any one of [1] to [5], wherein the raw material composition further contains water. [7] The method according to any one of [1] to [6], wherein the heating temperature in the step of heating the raw material composition is 60°C or more and 240°C or less. [8] The method according to any one of [1] to [7], further comprising a step of applying pressure to the heated raw material composition. [9] A method for producing a molded body, comprising a step of molding a molding composition produced by the method according to any one of [1] to [8] into a predetermined shape.

[10] The method according to [9], wherein the molded body is formed by injection molding, extrusion molding, insert molding, blow molding, or inflation molding.

[11] A method comprising: an inorganic solid material; and an organic material that is fluidized by heating to bond the inorganic solid materials together, wherein the mass m of the organic material １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２

[12] A molding material comprising: an inorganic solid material; and an organic material that bonds the inorganic solid materials together and that can be fluidized by heating, wherein a mass m of the organic material １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２ is greater than 1.

[0007] According to the present invention, it is possible to provide a method for producing a molding composition that allows a molded body to be easily obtained from a raw material composition that contains an inorganic material, a method for producing a molded body, a molding material, and a molded body.

[0008] 1A and 1B are cross-sectional views showing a molding device and a method of using the same according to an embodiment, a molding device and a method of using the same according to an embodiment, and a molding device and a method of using the same according to an embodiment.

[0009] Hereinafter, a method for producing a molding composition, a method for producing a molded body, a molding material, and a molded body according to an embodiment will be described. Note that the following embodiment shows one aspect of the present invention, does not limit the present invention, and can be arbitrarily modified within the scope of the technical concept of the present invention. Furthermore, each configuration and each feature of the embodiment can be arbitrarily combined.

[0010] <Method for producing molding composition> According to one embodiment, there is provided a method for producing a molding composition, comprising: (1) a step of obtaining a raw material composition containing inorganic solid materials and an organic material that is fluidized by heating and bonds the inorganic solid materials together (hereinafter referred to as a "raw material preparation step"); (2) a step of heating the raw material composition in a material space (hereinafter referred to as a "heating step"); and (3) a step of extruding the heated raw material composition from the material space as a molding composition (hereinafter referred to as an "extrusion step").

[0011] The present inventors have found that the above method allows a raw material composition containing an inorganic solid material to be extruded for molding. Steps (1) to (3) included in the above method are described below. Note that these steps may be performed in parallel.

[0012] (1) Raw Material Preparation Step First, the organic materials and inorganic solid materials are prepared. Then, they are mixed to obtain a raw material composition. Other materials may be added together with the organic materials and inorganic solid materials. Examples of other materials include water, additives, etc.

[0013] The order in which the materials are added is not particularly limited. All the materials may be mixed at once, or may be mixed in multiple stages.

[0014] The method for mixing the materials is not particularly limited. For example, mixing methods include manual stirring, mortar (manual or automatic), ball mill, planetary mill, vibration mill, rotor mill, hammer mill, disper mill, mixer, homogenizer, etc. The conditions for mixing are not particularly limited. For example, the materials can be mixed in the atmosphere at room temperature and normal pressure, but the temperature, pressure, atmosphere, etc. may be set as appropriate.

[0015] (1-1) Organic Material The organic material can have the function of fluidizing the entire composition so that molding such as injection molding or extrusion molding can be performed. The organic material is not particularly limited as long as it is a material that becomes fluid when heated and exhibits adhesive properties. The organic material can adhere and fix particles of the surrounding inorganic solid material to each other by being fluidized by heating and then cooled. This can improve the strength and density of the molded body.

[0016] (Types of Organic Materials) Examples of organic materials include, but are not limited to, plant-derived materials, animal-derived materials, synthetic resin materials, etc. The organic material may contain two or more of these materials.

[0017] For example, the organic material is a plant material. In this specification, "plant material" refers to a material contained in a plant or a derivative thereof. Examples of plant materials include lignin, cellulose, hemicellulose, sugar, etc. In terms of raw materials, there are no particular limitations, but examples include coniferous trees such as cedar, cypress, and pine; broad-leaved trees such as beech, castanea, and maple; grasses such as rice, wheat, bamboo, and sugarcane; grains such as rice, wheat, corn, millet, foxtail millet, barnyard millet, edamame, soybeans, adzuki beans, peas, and coffee beans; vegetables such as pumpkin, cabbage, lettuce, onion, carrot, radish, burdock, Chinese cabbage, broccoli, cauliflower, spinach, komatsuna, bok choy, tomato, watermelon, melon, bell pepper, paprika, cucumber, bamboo shoots, and tea leaves; and vegetables such as oranges, mandarins, Iyokan, strawberries, and bananas. Examples of organic materials include fruits such as lettuce, black currant, apple, persimmon, pear, cherry, pineapple, grape, blueberry, and peach; tubers such as potato, sweet potato, purple potato, taro, nagaimo, and yamaimo; mushrooms such as shiitake, maitake, enokitake, shimeji, nameko, and mushroom; seaweed such as sea lettuce, wakame, kombu, mekabu, hijiki, and nori; other plants (e.g., plant waste and residues discharged from plant factories); lignocellulosic materials; and artificial materials (e.g., waste and residues containing lignin and / or cellulose discharged from paper mills). The organic materials may be in any form, including, but not limited to, wood flour, wood chips, sawdust, plant stems, leaves, flowers, and plant-derived waste and residues. Plant materials such as isolated lignin, cellulose, hemicellulose, and sugars may also be used.

[0018] As used herein, "lignin" refers to a polymer having a basic structure formed by the polymerization of lignin monomers, which may be partially substituted with substituents and may bond or form a complex with other compounds. The type of lignin is not particularly limited, and may include S-type lignin, G-type lignin, H-type lignin, etc. The organic material may contain lignin having a structure formed by the polymerization of one or more types of lignin monomers. The lignin may contain monomers other than lignin monomers as polymerization units.

[0019] As used herein, "cellulose" refers to a polymer having a basic structure in which β-glucose is linearly polymerized via glycosidic bonds, and may be partially substituted with a substituent, may be bonded to other compounds (e.g., lignin), or may form a complex with other compounds.

[0020] As used herein, a "sugar" refers to a compound that has a carbonyl group or an aldehyde group and multiple hydroxyl groups, and may be partially substituted with a substituent, and may be bonded to or form a complex with another compound.

[0021] For example, the organic material is an animal material. As used herein, "animal material" refers to a material contained in an animal or a derivative thereof. Examples of animal materials include, but are not limited to, proteins.

[0022] For example, the organic material is a synthetic resin material. Examples of synthetic resin materials include thermoplastic resins. Specific examples include polyolefins (polyethylene, polypropylene, etc.), polystyrene, polyvinyl chloride, polyacrylonitrile, polyvinyl alcohol, polyesters (polyethylene terephthalate, etc.), polycarbonate, and polyamide. However, the raw material composition and the molding composition do not necessarily need to contain a synthetic resin material.

[0023] For example, the organic material may include one or more selected from the group consisting of lignin, cellulose, hemicellulose, and sugar. These materials can be obtained from plants. Therefore, using these materials as organic materials is preferable in that it allows the reuse of plant-derived resources that have not been sufficiently reused in the past, thereby contributing to sustainability.

[0024] Without being bound by theory, it is believed that lignin, cellulose, hemicellulose, and sugars fluidize the entire raw material composition at high temperatures, thereby enabling extrusion for molding. Furthermore, it is believed that these materials function like an adhesive, adhering and fixing particles of the inorganic solid material together after cooling, thereby maintaining the shape of the molded body and improving the strength of the molded body.

[0025] Since fibrous materials have resistance to tensile force, organic materials containing fibrous materials are preferred because they can improve the tensile strength of molded articles. Examples of fibrous materials that can be used as organic materials include cellulose, hemicellulose, nylon fiber, polyester fiber, and acrylic fiber. However, the raw material composition and molding composition do not necessarily need to contain fibrous materials.

[0026] (Particle size of organic material) The organic material can be refined and / or sorted until the maximum particle size falls within the desired range, for example, by crushing, chopping, or sieving the raw material. In this specification, the term "maximum particle size" refers to the size of the pores of a mesh sieve with square pores of a predetermined size used to separate "particles that passed through the sieve" from a particle group. In other words, the maximum particle size of the "particles that passed through the sieve" is the size of the pores of the sieve used. The maximum particle size of the organic material when mixed with other materials is, for example, 100 nm or more and 50 mm or less. If the maximum particle size of the organic material is less than 100 nm, the burden of crushing the material may be excessively large. If the maximum particle size of the organic material is more than 50 mm, the organic material may not be sufficiently fluidized even at high temperatures. The maximum particle size of the organic material is preferably 1 μm or more and 10 mm or less, 10 μm or more and 5 mm or less, or 100 μm or more and 1 mm or less. Preferably, the maximum particle size of the inorganic solid material is smaller than the diameter of the extrusion outlet 30 of the molding device 10, which will be described later. Note that these upper and lower limit values ​​can be combined arbitrarily.

[0027] (Amount of Organic Material Added) When the total amount of materials to be mixed is 100 parts by mass, the amount of organic material added is, for example, 50 parts by mass or more and 99 parts by mass or less, preferably 60 parts by mass or more and 90 parts by mass or less, or 70 parts by mass or more and 80 parts by mass or less. These upper and lower limit values ​​can be combined arbitrarily.

[0028] (1-2) Inorganic Solid Material The inorganic solid material can have the function of improving the density and / or durability (for example, fire resistance or insect resistance) of the molded body to be produced. The inorganic solid material may be any inorganic material that is solid at room temperature and normal pressure.

[0029] (Types of inorganic solid materials) The inorganic solid materials are not particularly limited, but include, for example, one or more selected from the group consisting of one or more types of concrete, one or more types of cement, one or more types of minerals, one or more types of metals, one or more types of ceramics, one or more types of glass, one or more types of slag, one or more types of lime, and one or more types of incineration ash, and composite materials thereof.

[0030] Concrete contains any known cementing material, any known coarse aggregate, any known fine aggregate, and water. For example, concrete contains cementing materials such as Portland cement, ground granulated blast furnace slag, silica fume, and fly ash; water; fine aggregates such as natural sand, blast furnace slag, and limestone sand; and coarse aggregates such as natural gravel, coarse blast furnace slag aggregate, limestone gravel, and steel slag roadbed material. Concrete may further contain an air entraining agent. The amount of each component in the concrete can be determined as desired.

[0031] Concrete may further contain any material other than those mentioned above. For example, concrete may further contain any additive such as a shrinkage reducing agent, a water reducing agent, a cement dispersant, etc. Concrete may further contain a fiber material, a metal material, a ceramic material, a plastic material, wood, wood chips, grass, paper, cloth, glass, soil, clay, paint, adhesive, etc.

[0032] Specifically, the concrete may be concrete structures of any shape, concrete waste, or concrete in various forms such as fragments, granules, or powder obtained by crushing or pulverizing concrete structures. The inorganic solid material may also be concrete waste, such as concrete rubble generated during the construction of structures such as buildings, roads, railways, and utility poles. Using concrete waste allows for the effective use of concrete resources that have not been sufficiently reused in the past, which is advantageous in terms of both cost and sustainability.

[0033] In this specification, "cement" refers to a powder that can be used as a raw material for building materials such as mortar, concrete, etc. Examples of cement include Portland cement, ground granulated blast furnace slag, silica fume, fly ash cement, alumina cement, etc.

[0034] As used herein, "mineral" may refer to a natural mineral, an artificial substance, or a material of biological origin. Examples of minerals, or mixtures or composites of minerals, include sand, gravel, silt, clay, gravel, stone, diatomaceous earth, etc.

[0035] As used herein, the term "metal" includes elemental metals and alloys. Examples of metals include iron, steel, aluminum, copper, brass, etc.

[0036] As used herein, the term "ceramics" refers to heat-treated inorganic materials. Examples of ceramics include metal oxides, metal carbides, metal nitrides, and inorganic materials that do not contain metal elements (e.g., diamond, silicon, carbon fiber, silicon carbide, fullerenes, and boron carbide).

[0037] As used herein, "glass" refers to a solid material comprising at least partially amorphous silicon oxide. Examples of glasses include soda-lime glass, quartz glass, silicate glass, borosilicate glass, etc.

[0038] As used herein, "slag" refers to a by-product produced when smelting metals from ores. Examples of slag include blast furnace slag, steelmaking slag, and non-ferrous slag.

[0039] In this specification, "lime" is a general term for quicklime (calcium oxide) and slaked lime (calcium hydroxide), and also includes materials containing calcium oxide and / or calcium hydroxide as the main component.

[0040] As used herein, "incineration ash" refers to the powder remaining after burning a substance. Examples of incineration ash include fly ash.

[0041] Preferably, the inorganic solid material comprises one or more selected from the group consisting of concrete, cement, sand, gravel, stone, diatomaceous earth, slag, gypsum, lime, ash, fly ash, metal, brick, and glass. These materials are advantageous in that they are easily available and have not been fully utilized in the past.

[0042] (Particle size of inorganic solid material) As with organic materials, inorganic solid materials can be refined and / or selected until the maximum particle size falls within the desired range, for example, by crushing or sieving the raw material. The maximum particle size of the inorganic solid material is, for example, 100 nm to 50 mm. If the maximum particle size of the inorganic solid material is less than 100 nm, the crushing burden on the material may be excessively large. If the maximum particle size of the inorganic solid material is greater than 50 mm, the gaps between the constituent particles of the produced molded body may become large, potentially reducing the strength of the entire molded body. The maximum particle size of the inorganic solid material is preferably 1 μm to 10 mm, 10 μm to 5 mm, or 100 μm to 1 mm. Preferably, the maximum particle size of the inorganic solid material is smaller than the diameter of the extrusion outlet 30 of the molding device 10 described below. Note that these upper and lower limits can be combined arbitrarily.

[0043] (Amount of inorganic solid material added) When the total amount of materials to be mixed is 100 parts by mass, the amount of inorganic solid material added is, for example, 10 parts by mass or more but less than 50 parts by mass, and preferably 15 parts by mass or more and 45 parts by mass or less, 20 parts by mass or more and 40 parts by mass or less, or 25 parts by mass or more and 35 parts by mass or less. These upper and lower limits can be combined arbitrarily.

[0044] When the total amount of the organic material and the inorganic solid material is 100 parts by mass, the amount of the organic material added is, for example, more than 50 parts by mass and not more than 99 parts by mass. That is, the amount of the inorganic solid material added is, for example, not less than 1 part by mass and less than 50 parts by mass. The mass m of the organic material １ and the mass of the inorganic solid material m ２ Relative to m １ / m ２ is, for example, greater than 1 and less than or equal to 100. Preferably, m １ / m ２ may be 1.5 or more and 50 or less, 2 or more and 20 or less, 3 or more and 10 or less, or 4 or more and 8 or less. These upper and lower limit values ​​can be arbitrarily combined. When the amount of the organic material added is less than 50 parts by mass (i.e., m １ / m ２ If the ratio is 1 or less), the amount of organic material contained in the molding composition will be insufficient, and sufficient fluidity may not be achieved during molding. As a result, the molding composition may not be able to be injected (see the Examples below for details. However, since the Examples below only examine pressures up to a certain upper limit, it is considered that injection may be possible depending on the applied pressure even when the amount of organic material added is less than 50 parts by mass). If the amount of organic material added is more than 99 parts by mass (i.e., the amount of inorganic solid material added is less than 1 part by mass), the amount of flammable components in the molded body will be high, and sufficient fire resistance may not be achieved. Furthermore, the molded body may not be able to exhibit sufficient resistance to insect damage and mold growth.

[0045] (1-3) Water In the raw material preparation step, water may be added to the organic material and the inorganic solid material. In this case, the raw material composition contains water. The timing of adding water is not particularly limited, but in order to allow water to permeate the raw material composition before heating, it is preferable to add water to the raw material composition before the heating step.

[0046] According to the examples described below, the addition of water increased the fluidity of the molding composition, making it easier to extrude, while also tending to increase the porosity of the molding composition. Without being bound by theory, the effect of water will be considered below. A possible mechanism for the increase in fluidity is that high-temperature steam denatures the organic material, resulting in improved fluidity. For example, if the organic material contains lignin or hemicellulose, a possible mechanism for the improvement is that these components are decomposed by high-temperature steam, resulting in improved fluidity. A possible mechanism for the increase in porosity is that the water contained in the molding composition evaporates upon heating, resulting in the formation of voids in the molding composition.

[0047] In this specification, the ratio of the mass of added water to the total mass of components other than water in the raw material composition is referred to as "moisture content." A moisture content of 0% means that no water was added, and a moisture content of 100% means that the same amount of water was added as the mass of components other than water in the raw material composition. The moisture content is, for example, 0% to 200%, 5% to 100%, or 10% to 50%. These upper and lower limits can be combined arbitrarily.

[0048] (1-4) Additives In addition to the above organic materials, inorganic solid materials, and water, other additives may be added as needed. Examples of additives include adhesives, plasticizers, reinforcing materials, colorants, dispersants, antioxidants, flame retardants, stabilizers, and foaming agents.

[0049] In addition, an alkali component, another organic material, another inorganic solid material, or the like may be further added for the purposes of making the molding composition suitable for molding methods such as extrusion molding and injection molding, improving the fillability of the molding composition into a mold, and / or improving the properties of the molded body (for example, flexural strength, compressive strength, tensile strength, surface properties, etc.).

[0050] The form of the raw material composition is not particularly limited. For example, in the raw material composition, the organic material and the inorganic solid material may be mixed in the form of powder or particles. The raw material composition may be in a powder form (including a powder form moistened with water) or may be solidified into a predetermined shape such as a pellet. Preferably, the raw material composition has the form of a powder in which a powder of an organic material and a powder of an inorganic solid material are mixed.

[0051] (2) Heating Step In the heating step, the raw material composition is heated to a predetermined temperature. In the heating step, heat treatment is carried out so as to fluidize the organic material. Preferably, the organic material fluidized by the heat treatment penetrates into the gaps between the particles of the inorganic solid material, resulting in substantially the entire molding composition being fluidized. The heating method is not particularly limited, and any heating means such as a hot plate or a heating furnace can be used.

[0052] (2-1) Heat Treatment The heating temperature in the heating step is, for example, 60°C or higher and 240°C or lower. If the heating temperature is lower than 60°C, the organic material may not be sufficiently fluidized, making it difficult to extrude the molding composition. If the heating temperature is higher than 240°C, the organic material may carbonize or ignite. Preferably, the heating temperature is 80°C or higher and 230°C or lower, 100°C or higher and 200°C or lower, or 120°C or higher and 180°C or lower. These upper and lower limits can be combined arbitrarily. The heating temperature may be changed as appropriate during the molding process.

[0053] (2-2) Pressure Treatment In addition to the heat treatment, a pressure treatment can be performed in which pressure is applied to the raw material composition. The pressure treatment can be performed after the temperature has been raised to the heating temperature, in parallel with the temperature increase to the heating temperature, or before the heat treatment. For example, the above method can further include a step of applying pressure to the heated raw material composition (hereinafter referred to as the "pressure step"). By applying pressure to the heated raw material composition, the material is compressed while the organic material is in a molten state, thereby reducing voids inside the molding composition. By molding using this molding composition, a molded body with few voids can be formed.

[0054] The pressure applied to the raw material composition during the pressure treatment is, for example, 0.01 MPa or more and 400 MPa or less. If the applied pressure is less than 0.01 MPa, the raw material composition may not be sufficiently pressurized. If the applied pressure is 400 MPa or more, excessive pressure may adversely affect the molding device. Preferably, the applied pressure is 0.1 MPa or more and 300 MPa or less, 1 MPa or more and 200 MPa or less, or 10 MPa or more and 100 MPa or less. Note that these upper and lower limit values ​​can be combined arbitrarily. The applied pressure may be changed as appropriate during the molding process.

[0055] Before the heat treatment and / or pressure treatment, a step of selecting a heating temperature and / or applied pressure that can extrude the molding composition may be performed depending on the molding conditions. The molding conditions include, for example, the type, amount, and form of the organic material and inorganic solid material contained in the raw material composition, the amount of water in the raw material composition, the processing of the raw material powder, the size and shape of the mold used, and the diameter of the extrusion opening. For example, the heating temperature and / or applied pressure can be selected by referring to a database that records heating temperatures and / or applied pressures that are suitable for extruding the molding composition for various combinations of molding conditions.

[0056] (2-3) Configuration of the Molding Apparatus An example of the configuration of a molding apparatus will be described below with reference to the drawings. Figures 1 to 3 are cross-sectional views of a molding apparatus 10 and a method for using the molding apparatus 10. The molding apparatus 10 accommodates and heats a raw material composition P1, and applies pressure to the heated raw material composition P1 by sandwiching it from above and below, thereby extruding it to the outside as a molding composition P2.

[0057] The molding device 10 may have a storage means for storing the raw material composition P1 in the material space, a heating means for heating the raw material composition P1 in the material space, a pressurizing means for applying pressure to the raw material composition P1 in the material space, an extrusion means for extruding the heated and pressurized raw material composition P1 from the material space to the outside as a molding composition P2, and a molding means for molding the extruded molding composition P2 into a predetermined shape.

[0058] For example, as shown in Fig. 1, a molding apparatus 10 has a lower member 12 and an upper member 14. The lower member 12 and the upper member 14 are joined together to form a cavity C (an example of a "material space") capable of containing a raw material composition P1 therein. Preferably, the lower member 12 and the upper member 14 are made of a material with excellent heat conductivity. More preferably, the lower member 12 and the upper member 14 are made of a metal.

[0059] The lower member 12 has a lower heating member 20 (an example of a "heating means"), a base 22, and a storage member 24 (an example of a "storage means"). The lower heating member 20 is attached to the underside of the base 22 and heats the molding device 10 from below. The storage member 24 is a cylindrical member attached to the upper surface of the base 22 and supported by the base 22. The storage member 24 has an internal space capable of storing the raw material composition P1. An extrusion port 30 penetrating the peripheral wall is formed in the peripheral wall of the storage member 24.

[0060] The upper member 14 has an upper heating member 26 and a pressing member 28. The upper heating member 26 (an example of a "heating means") is attached to the upper surface of the pressing member 28 and heats the molding apparatus 10 from above. The pressing member 28 (an example of a "pressure means" and an "extrusion means") has a piston shape so that it can be inserted into the internal space of the accommodating member 24 from above. A cavity C is formed by inserting the pressing member 28 into the internal space of the accommodating member 24. The cavity C is sealed except for an extrusion port 30.

[0061] A method for heating the raw material composition P1 using the molding apparatus 10 will be described. First, the molding apparatus 10 is heated to a predetermined temperature by the lower heating member 20 and the upper heating member 26. Next, the raw material composition P1 is introduced into the internal space of the housing member 24. The raw material composition P1 is heated by the preheated molding apparatus 10. Thereafter, as shown in FIG. 1 , a pressing member 28 is inserted into the internal space of the housing member 24, thereby joining the lower member 12 and the upper member 14. The raw material composition P1 is pressed from above by the pressing member 28. This promotes heat exchange between the raw material composition P1 and each member of the molding apparatus 10, and compresses the raw material composition P1 within the cavity C. As a result, the entire raw material composition P1 is heated.

[0062] (3) Extrusion Step In the extrusion step, the heated raw material composition P1 is extruded to the outside as a molding composition P2. An example of the extrusion step using the molding apparatus 10 will be described below with reference to FIGS.

[0063] As shown in FIG. 2 , further pressure is applied in the direction in which the lower member 12 and the upper member 14 approach each other. For example, a downward load is applied to the upper surface of the upper heating member 26, thereby pressing the lower member 12 and the upper member 14 together. The sufficiently heated organic material becomes fluidized and can enter the gaps between the particles of the inorganic solid material through compression. This allows the organic material and the inorganic solid material to mix more homogeneously, increasing the contact area between them. The fluidized organic material functions as a matrix material for the inorganic solid material, fluidizing the entire raw material composition P1. As a result, as shown in FIG. 2 , the raw material composition P1 is extruded under pressure from the cavity C through the extrusion port 30 into the external space as a molding composition P2. This molding composition P2 is ready for molding.

[0064] It is preferable that the molding apparatus 10 is capable of performing both the heating step and the extrusion step, since this allows molding of the molding composition P2 to be carried out easily.

[0065] <Method for producing a molded body> According to one embodiment, there is provided a method for producing a molded body, comprising: (4) a step of molding the molding composition produced by the above method into a predetermined shape (hereinafter referred to as the "molding step"). The molding step may be performed subsequent to or in parallel with the above extrusion step. Hereinafter, an example of a method for producing a molded body from molding composition P2 will be described with reference to FIG. 3.

[0066] (4) Molding Step FIG. 3 shows an example of a method for processing molding composition P2 using molding apparatus 10. In FIG. 3, a mold 40 is used to mold molding composition P2. As shown in FIG. 3, mold 40 is coupled to the outlet of extrusion nozzle 30. Mold 40 has a female mold 42 and a male mold 44. A recess having a predetermined shape for forming a molded product is formed in female mold 42. A protrusion having a predetermined shape for forming a molded product in cooperation with female mold 42 is formed in male mold 44. When female mold 42 and male mold 44 are coupled, the recess of female mold 42 and the protrusion of male mold 44 do not completely contact each other, forming a gap G corresponding to the shape of the molded product.

[0067] The mold 40 (an example of a "molding means") is coupled to the housing member 24 so that the recess of the female mold 42 communicates with the extrusion port 30. With the housing member 24 and the mold 40 coupled together, the molding composition P2 is extruded from the extrusion port 30 and fills the gap G. The female mold 42 and the male mold 44 are then separated, and the molding composition P2 cools and solidifies on the protrusion of the male mold 44. This results in a molded product having a shape corresponding to the gap G.

[0068] In this way, by extruding molding composition P2 fluidized by the organic material from extrusion port 30 of molding device 10, a molded article having any shape corresponding to mold 40 can be produced. Note that the molding method of molding composition P2 is not limited to the above example. Although the method shown in Figure 3 is injection molding, various molding methods such as extrusion molding, insert molding, blow molding, and inflation molding can be used for molding composition P2 extruded from extrusion port 30.

[0069] (5) Other Treatments The raw material composition may be subjected to an appropriate pretreatment. The pretreatment may be performed, for example, before or after mixing the raw materials in the raw material preparation step. Specifically, the pretreatment may involve a treatment to depolymerize the polymer (e.g., alkali treatment, autoclave treatment, or enzyme treatment). Any base, such as KOH, NaOH, or LiOH, may be used for the alkali treatment. Other pretreatments, such as acid treatment, oxidation treatment, blasting treatment, hydrolysis treatment, and bleaching treatment, may also be performed. After pretreatments such as alkali treatment or acid treatment, a washing treatment may be performed. Specifically, washing treatments such as water washing, washing in a neutralization chamber, and neutralization treatment with acid or alkali may be performed to bring the raw material to a predetermined state (e.g., a predetermined pH). Such pretreatments and / or washing treatments may be performed to provide the raw material composition P1 containing an organic material and an inorganic solid material with properties and characteristics suitable for a desired molding method.

[0070] When the raw material composition P1 contains a fibrous material, the fiber direction of the fibrous material may be controlled by known techniques so as to obtain a molding composition P2 having properties and characteristics suitable for the desired molding method, or so as to obtain a molded body having the desired strength characteristics.

[0071] As described above, by appropriately performing operations such as heating, pressurization, addition of water, and pretreatment on a raw material composition containing an organic material and an inorganic solid material, a molding composition having properties and characteristics (e.g., fluidity, thermal shear resistance, viscosity, density, etc.) suitable for a desired molding method can be obtained. For example, a molding composition having a desired shear capacity or shear rate can be obtained. This allows known simple molding methods to be applied to raw material compositions containing inorganic solid materials. Therefore, a molded body having a desired shape can be easily obtained from a raw material composition containing inorganic solid materials. Furthermore, by using an organic material to bond inorganic solid materials together, the strength of the molded body can be improved compared to a molded body made only of inorganic solid materials.

[0072] <Molding Material> According to one embodiment, the molding material includes an inorganic solid material and an organic material that is fluidized by heating and bonds the inorganic solid materials together, and the mass m of the organic material １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２ A molding material is provided, wherein:

[0073] The molding material is used as a material for forming a molded body. The term "molding material" includes both the raw material composition P1 and the molding composition P2 described above. The form of the molding material is not particularly limited, and may be a mixture of solid powders such as raw material composition P1, an at least partially fluidized composition such as molding composition P2, or a composition in a solidified state from a fluid. Preferably, the molding material can be used in a molding method applicable to thermoplastic resin materials, such as injection molding, extrusion molding, blow molding, or inflation molding.

[0074] In the molding material, m １ / m ２is, for example, 100 or less. Preferably, m １ / m ２ may be 1.5 or more and 50 or less, 2 or more and 20 or less, 3 or more and 10 or less, or 4 or more and 8 or less. These upper and lower limit values ​​can be combined arbitrarily.

[0075] The molding material has a porosity of, for example, 0% to 90%. The porosity is measured by Archimedes' method. Preferably, the porosity of the molding material is 10% to 80%, 20% to 70%, 25% to 60%, or 30% to 50%.

[0076] <Molded body> According to one embodiment, a molded body includes an inorganic solid material and an organic material that bonds the inorganic solid materials together and can be fluidized by heating, and the organic material has a mass m １ and the mass of the inorganic solid material m ２ Relative to m １ / m ２ is greater than 1.

[0077] In the molded body, m １ / m ２ is, for example, 100 or less. Preferably, m １ / m ２ may be 1.5 or more and 50 or less, 2 or more and 20 or less, 3 or more and 10 or less, or 4 or more and 8 or less. These upper and lower limit values ​​can be combined arbitrarily.

[0078] The molded body has a porosity of, for example, 0% to 90%. The porosity is measured by Archimedes' method. Preferably, the porosity of the molded body is 10% to 80%, 20% to 70%, 25% to 60%, or 30% to 50%.

[0079] The present invention will be described below with reference to experimental examples, but the present invention is not limited to the following experimental examples.

[0080] Example 1-1 (Production of Raw Material Composition) Cedar wood flour (product name: Domestic Cedar Flour, 300 μm pass, manufactured by Naka Wood Co., Ltd.) was prepared as an organic material. 300 μm pass refers to passing through a sieve with a mesh size of 300 μm. Therefore, the maximum particle size of the wood flour used was approximately 300 μm. Concrete powder obtained by pulverizing concrete rubble was prepared as an inorganic solid material. Specifically, the concrete rubble was pulverized and passed through a sieve with a mesh size of 105 μm to obtain concrete powder with a maximum particle size of approximately 105 μm. The organic material and inorganic solid material were mixed at a mass ratio of 4:1. 10 parts by mass of water was added to 100 parts by mass of this mixture and mixed. This resulted in a powdered raw material composition.

[0081] (Heating and Injection) The raw material composition was heated and injected using the molding apparatus 10 shown in FIG. 1 . Specifically, the lower member 12 and the upper member 14 of the molding apparatus 10 were preheated to 180°C by the heating members 20 and 26, respectively, and then the powdered raw material composition P1 was introduced into the cavity C within the molding apparatus 10. Next, a 1-ton load was applied in the direction in which the lower member 12 and the upper member 14 approached each other and maintained for 5 minutes, and it was confirmed whether the molding composition P2 was injected from the extrusion port 30 of the housing member 24 of the lower member 12. If injection was not confirmed after applying and maintaining a 1-ton load for 5 minutes, the load was increased by 1 ton every 5 minutes up to a maximum of 7 tons, and the presence or absence of injection and the load at which injection was confirmed were confirmed. As a result, when a 2-ton load was applied, the molding composition P2 was injected from the extrusion port 30. Note that the inner diameter of the housing member 24 of the molding apparatus 10 used was 14 mm, and the area to which the load was applied was approximately 154 mm. ２ Therefore, a load of 2 tons is converted into a pressure of approximately 128 MPa.

[0082] Examples 1-2, 1-3, and Comparative Example 1 (Changing the Mass Ratio of Organic Material to Inorganic Solid Material) In Examples 1-2, 1-3, and Comparative Example 1, the presence or absence of injection was confirmed in the same manner as in Example 1-1, except that the mass ratio of the organic material to the inorganic solid material was changed as shown in Table 1 below. Specifically, the mass ratio of the organic material to the inorganic solid material was changed within a range of 3:1 to 1:1. As a result, injection was confirmed in Examples 1-2 and 1-3, but injection of molding composition P2 was not confirmed in Comparative Example 1, even when a load of 7 tons was applied.

[0083] Examples 2-1 to 2-5 (Changing Heating Temperature) In Examples 2-1 to 2-3, the heating temperature was changed from that of Example 1-1 (where the mass ratio of organic material to inorganic solid material was 4:1), as shown in Table 1 below, and the presence or absence of injection was confirmed. In Examples 2-4 and 2-5, the heating temperature was changed from that of Example 1-2 (where the mass ratio of organic material to inorganic solid material was 3:1), and the presence or absence of injection was confirmed. As a result, injection of molding composition P2 was confirmed in all of the examples.

[0084] Examples 3-1 to 3-7, Comparative Example 2 (Changes in Water Content) In Example 3-1, the presence or absence of injection was confirmed in the same manner as in Example 1-1, except that 100 parts by mass of water was added to 100 parts by mass of the mixture of organic material and inorganic solid material, as shown in Table 1 below. In Examples 3-2 to 3-7, the heating temperature and the mass ratio of the organic material to the inorganic solid material were variously changed from those in Example 3-1, and the presence or absence of injection was confirmed. As a result, injection was confirmed in Examples 3-1 to 3-7, but injection of molding composition P2 was not confirmed in Comparative Example 2, even when a load of 7 tons was applied. Note that although injection was confirmed in Example 3-1, the specific load value is unknown.

[0085] <Examples 4-1 and 4-2> (No Use of Water) In Examples 4-1 and 4-2, whether or not injection occurred was confirmed without adding water, as shown in the following Table 1. As a result, injection of molding composition P2 was confirmed in both Examples.

[0086] Example 5 (Use of Thermoplastic Resin) In Example 5, the presence or absence of injection was confirmed in the same manner as in Example 1-1, except that polyethylene (product name: small polyethylene fine powder, manufactured by Featherfield Co., Ltd.) was used as the organic material. As a result, injection of molding composition P2 was confirmed.

[0087] Table 1 below shows the experimental parameters and results for each example and comparative example. The "moisture content" column indicates the ratio of the amount of water added (by mass) to the total mass of the organic material and inorganic solid material. The "success / failure" column indicates "Yes" if injection was confirmed, and "No" if injection was not confirmed up to a load of 7 tons.

[0088] As described above, it was confirmed that when the mass ratio of the organic material to the inorganic solid material was greater than 1:1, the molding composition could be extruded even without the inclusion of a synthetic resin material. It was also confirmed that the molding composition could be extruded even when a synthetic resin material (polyethylene) was used instead of wood flour. On the other hand, when the mass ratio of the organic material to the inorganic solid material was 1:1 or less, as in Comparative Examples 1 and 2, injection of molding composition P2 was difficult at loads up to at least 7 tons. On the other hand, as the mass ratio of the organic material to the inorganic solid material increased, the injection load decreased, and injection tended to become easier. Similarly, as the heating temperature and moisture content increased, the injection load decreased, and injection tended to become easier.

[0089] <Evaluation of Porosity> As shown in Table 2 below, the molding composition P2 injected in the examples was immersed in alcohol (95% ethanol) for 24 hours and then removed. In each example, an increase in the mass of molding composition P2 was confirmed before and after the immersion experiment. The increase in mass before and after immersion was divided by the mass before immersion to calculate the "alcohol absorption rate." The "porosity" was also calculated using Archimedes' law. That is, the mass before immersion (bone-dry state) (dry mass), the mass after immersion (water-saturated mass), and the mass in the alcohol solution (mass in water) were each measured, and the value of (water-saturated mass - dry mass) / (water-saturated mass - mass in water) was calculated as the "porosity."

[0090]

[0091] As described above, it was confirmed that the alcohol absorption rate and porosity tend to decrease as the content of the organic material in the raw material composition increases. It was also confirmed that the alcohol absorption rate and porosity tend to decrease as the water content decreases. It is believed that the smaller the porosity, the more the organic material penetrates into the gaps between the particles of the inorganic solid material, adhering the particles of the inorganic solid material together.

[0092] 10...molding device, 12...lower member, 20...lower heating member, 22...base, 24...accommodating member, 30...extrusion port, 14...upper member, 26...upper heating member, 28...pressure member, 40...mold, 42...female mold, 44...male mold, C...cavity, P1...raw material composition, P2...molding composition.

Claims

1. 1. A method for producing a molding composition, comprising: obtaining a raw material composition including inorganic solid materials and an organic material that is fluidized by heating and bonds the inorganic solid materials together; heating the raw material composition in the material space; extruding the heated raw material composition from the material space as the molding composition; A method comprising:

2. The organic material is a plant material. The method of claim 1.

3. The organic material comprises one or more selected from the group consisting of lignin, cellulose, hemicellulose, and sugars.

3. The method according to claim 1 or 2.

4. The inorganic solid material comprises one or more selected from the group consisting of one or more types of concrete, one or more types of cement, one or more types of minerals, one or more types of metals, one or more types of ceramics, one or more types of glass, one or more types of slag, one or more types of lime, and one or more types of incineration ash, and composite materials thereof; 3. The method according to claim 1 or 2.

5. The mass m of the organic material １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２ is greater than 1, 3. The method according to claim 1 or 2.

6. The raw material composition further contains water.

3. The method according to claim 1 or 2.

7. The heating temperature in the step of heating the raw material composition is 60°C or higher and 240°C or lower.

3. The method according to claim 1 or 2.

8. further comprising applying pressure to the heated feedstock composition.

3. The method according to claim 1 or 2.

9. A method for producing a molded body, comprising: A method comprising the step of molding a molding composition produced by the method of claim 1 or 2 into a predetermined shape.

10. The molded body is molded by injection molding, extrusion molding, insert molding, blow molding, or inflation molding.

10. The method of claim 9.

11. an inorganic solid material; an organic material that is fluidized by heating and bonds the inorganic solid materials together; Including, The mass m of the organic material １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２ is greater than 1, Molding material.

12. an inorganic solid material; an organic material that bonds the inorganic solid materials together and that can be fluidized by heating; Including, The mass m of the organic material １ and the mass m of the inorganic solid material ２ Relative to m １ / m ２ is greater than 1, Molded body.