JP2010155393A - Flow molding of lumber using solvent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a flow-molded article of lumber, using a solvent having a hydrogen bond capability and the flow-molded article obtained by the method. <P>SOLUTION: In the method for manufacturing the flow-molded article of a vegetable material, the vegetable material impregnated with the solvent having a weak self-cohesive force and the hydrogen bond capability is charged in a mold and pressurized at room temperature or while being heated, so that the mutual positional relationship of component cells is changed, and the material is fluidized, packed in the mold by being fluidized/deformed, compressed, and consolidation-molded to be molded into the molded article having a three-dimensional shape. The flow-molded article of the vegetable material having a cup-shaped deep bottom structure which is manufactured by the method is provided. The vegetable material is added with the solvent, deformed by being pressurized, packed in the mold, compressed to obtain the flow-molded article with a complicated three-dimensional shape molded. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a fluid molded body of a plant-based material, and more specifically, a plant-based material into which a solvent having a small self-aggregation force and a hydrogen bonding ability is injected is put into a mold, The present invention relates to a method for producing a fluid molded body of a plant-based material, which is formed by pressurizing and deforming to flow-fill in a mold, and compacting by applying a compression force to form a three-dimensional shape, and a molded body obtained by the method. Is. The present invention forms a plant material such as wood or bamboo, which is expected to be highly utilized as a reproducible resource, into a three-dimensional shaped molded body with a simple apparatus and mild processing conditions. The present invention provides a method for producing a fluid molded body of a plant material and a product thereof.

  Plant-based materials such as wood, bamboo, vegetation, and agricultural waste are reproducible materials and have recently attracted attention as materials that replace plastics that are made from petroleum, which is a buried resource. In order to form the plant-based material into a desired three-dimensional shape, as a conventional technique, a method in which plate-shaped wood is pressed with a mold (Patent Document 1), or a rod-shaped wood is added with a mold. A method of forming by pressing (Patent Document 2) has been proposed.

  As another prior art, there has been proposed a method (Patent Document 3) in which a resin is mixed into powdered wood so as to have fluidity, which is poured into a mold, and cooled and solidified. In the method of pressing and molding these rod-like or plate-like wood with a mold, the cells constituting the material are deformed by being compressed by the pressurization, so the amount of deformation due to compression is limited. The shape that can be manufactured is limited. In addition, in the above-described method using wood powder as a raw material, much time and energy are required for pulverizing wood.

  Therefore, the present inventors have previously proposed a method for forming a plant-based material that is deformed by changing the mutual positional relationship of constituent cells with respect to the plant-based material (Patent Document 4). This method has the advantage that the material does not need to be powdered and can be formed by a simple device such as a press. In order to move the constituent cells to each other by this method, the intercellular layer existing between the cells is destroyed, and the destruction of the intercellular layer includes the presence of a certain amount of adsorbed moisture on the intercellular layer, and A temperature condition exceeding 100 ° C. is required.

  However, in the above method, in the middle of molding, the evaporated water may be dissipated from the mold clearance and the flow conditions may change, and excessive moisture to suppress the change of moisture due to evaporation. Since the injection of pressure may cause an abnormal increase in pressure inside the material such as puncture, which may cause molding defects and mold breakage, it is a technical problem to solve them in this technical field. It was.

JP 2006-076055 A JP 2004009567 A JP 2002-146195 A JP 2008-036941 A

  Under such circumstances, the present inventors can reliably solve the problems of the prior art in view of the prior art, and efficiently form the plant-based material with simple equipment and processes. We have earnestly researched with the goal of developing new molding technology that makes it possible.

  As a result, the present inventors have compared the molding method using water by impregnating a plant-based material with a solvent having a low self-aggregation force, that is, a cohesive energy density and a hydrogen bonding ability. The present inventors have found that it is possible to change the mutual positional relationship of cells to flow and deform the material, and thereby to greatly reduce the molding temperature and pressure, and to complete the present invention. .

  The present invention forms a plant material such as wood or bamboo, which is expected to be highly utilized as a reproducible resource, into a three-dimensional shaped molded body with a simple apparatus and mild processing conditions. An object of the present invention is to provide a method for producing a fluid molded body of a plant material and a product thereof.

The present invention for solving the above-described problems comprises the following technical means.
(1) A plant material impregnated with a solvent having a small self-aggregation force and a hydrogen bonding ability is placed in a mold, and pressure is applied at room temperature or under heating, thereby changing the mutual positional relationship between constituent cells. A flow molding body of a plant-based material, characterized in that the material is flow-filled into the mold by flowing and deforming, and formed into a three-dimensional shaped body by compacting by applying a compressive force. Manufacturing method.
(2) The method for producing a fluid molded body of a plant material according to the above (1), wherein the solvent having a small self-aggregating force and having a hydrogen bonding ability is dimethyl sulfoxide (DMSO) or dimethylformamide.
(3) A plant-based material is put into a mold, the material is flowed and deformed, and the mold is flowed and filled to apply a compressive force of about 10 MPa to 300 MPa to form a three-dimensional shape. The manufacturing method of the fluid molded object of the plant-type material as described in said (1) or (2) shaped to a body.
(4) The fluidized molded body of the plant-based material according to any one of (1) to (3), wherein the plant-based material before molding is separated into a single or a plurality as a bulk and is put into a mold. Manufacturing method.
(5) The plant-based material according to any one of (1) to (4), wherein the fiber orientation of the obtained molded body is controlled by adjusting the arrangement of the plant-based material before molding in the mold. A method for producing a fluid molded body.
(6) Any of (1) to (5) above, wherein the molding temperature and / or the molding pressure in the molding process is controlled to suppress thermal decomposition of the molded body and reflect the texture of the raw material on the molded body. A method for producing a fluid molded body of a plant material according to claim 1.
(7) The method for producing a fluid molded body of a plant material according to any one of (1) to (6), wherein the plant material is wood, bamboo, vegetation, or agricultural waste.
(8) A deep-bottom shaped molded body produced by the method according to any one of (1) to (7), wherein: 1) a compression molded body of dimethylsulfoxide (DMSO) or dimethylformamide-impregnated wood Yes, 2) The texture of the raw material is reflected in the molded body, and 3) a fluid molded body of plant material characterized by having a cup-like deep bottom structure.

Next, the present invention will be described in more detail.
In the present invention, a plant-based material impregnated with a solvent having a small self-aggregation force and a hydrogen bonding ability is placed in a mold, and pressure is applied at room temperature or under heating, thereby reciprocal positional relationship between constituent cells. It is characterized in that the material is fluidized and deformed by being changed and fluidized and filled in a mold, and compacted by applying a compressive force and shaped into a three-dimensional shaped product.

  In the present invention, a solvent having a small self-cohesion force, that is, a cohesive energy density is small and has a hydrogen bonding ability is high in polarity and hydrogen bonds with an OH group of wood, but has a low cohesive energy density, that is, a proton. Defined as meaning organic / inorganic liquids such as dimethyl sulfoxide, dimethylformamide, etc., which have low accepting power or donating power.

The solvent having a small self-cohesion force used in the present invention and having a hydrogen bonding ability will be described in more detail. The solvent used in the present invention has a hydrogen bonding ability of 1 cm ⁻¹ or more and an aggregation energy of 50 kJ / mol or less. Defined as a thing. Here, the hydrogen bonding ability is the difference between the wavelength (wave number) of the infrared absorption band of -OD stretching vibration in a dilute benzene solution of deuterium methanol and the absorption band wavelength (wave number) of the target liquid in a dilute solution. Indicates. This shift amount becomes an index indicating the magnitude of the proton accepting power of the target liquid. The amount of shift from the benzene solution of the infrared absorption band wavelength of C = O stretching vibration of acetophenone indicates proton donating power.

However, since both shift amounts are based on the absorption wavelength band of -OD in benzene, the π electrons of benzene show a certain degree of proton acceptability, so the shift amount may be negative. To do. However, in the present invention, this value is adopted because a liquid with a slight accepting / donating power is not included in the range [Document: Kagiya, T, Sumida, Y, Inoue, T, Bull. Chem. Soc. Jap. , 41, 767-773 (1968), Crowly, JD, Teague, GS, Lowe, JW, J. et al. Paint Technol. , 38, 269-280 (1966)]. The cohesive energy is derived from the cohesive energy density (energy required to evaporate a 1 cm ³ liquid) [literature: Hansen, CM, J. et al. Paint Technil. 39: 505, 104-117 (1967)].

  In the present invention, the plant-based material means a renewable organic resource synthesized by a plant using solar energy, water, soil, and air. The plant material which is a raw material of the fluid molded body of the present invention is not particularly limited, and the present invention can be applied to all plant materials having cell walls. Specifically, for example, wood, bamboo, herbs, and agricultural waste are exemplified as particularly suitable materials.

  In the case of the method for producing a fluid molded body of the present invention, the raw material is of a size that can be put into a mold such as a mold in order to change the mutual positional relationship between cells constituting the plant-based material and greatly deform the premise shape. If there is, the shape is not particularly limited. In addition, even if the plant-based material before molding is separated into a plurality as a bulk, the material is separated at the cellular level in the molding process, and these are integrated after molding. The method for producing a fluid molded body of the present invention can be applied in the same manner whether the bulk is single or plural.

  When the method for producing a fluid molded body of the present invention is applied to a plant-based material having a fiber structure, the fiber is hardly broken during the molding process. Therefore, the molded body may have a fiber structure as it is. Is possible. Moreover, since the arrangement of the plant-based material before molding in a mold such as a mold affects the fiber orientation after molding, the fiber orientation of the molded body can be controlled by the plant-based material arrangement before molding. .

  Next, the molding process of the plant material in the present invention will be described. In the present invention, the plant-based material impregnated with the above-described solvent is put into a mold, and pressure is applied at room temperature or under heating to change the mutual positional relationship of the constituent cells, thereby causing the material to flow and deform. Thus, the greatest feature is that it is fluidly filled into a mold, compacted by applying a compressive force, and shaped into a three-dimensional shaped product.

  According to the method for producing a fluid molded body of the present invention, the deformation of the plant material is caused not only by the compression of the cells but also by the movement of the cells. Compared to molding using only cell compression, the cell compression and cell movement enable a very large deformation.

  As a specific method for molding, for example, the bamboo impregnated with the above-mentioned solvent is put into a mold heated to about 200 ° C. and pressurized at about 1 MPa to 500 MPa, preferably 10 MPa to 300 MPa, more preferably about 200 MPa. . The bamboo under pressure is deformed by changing the mutual positional relationship between the constituent cells, and is fluidly filled into the mold. When fluid filling is completed, the pressure is released and the molded body is taken out. FIG. 1 shows an example of a molding method in the molding process of the present invention.

  FIG. 2 shows the compression test results of each wood sample in a completely dry state, a saturated water state, and a state of being impregnated with DMSO (dimethyl sulfoxide). It can be seen that the DMSO sample has already started to flow even though the consolidation has not been completed, and can be made to flow with a smaller displacement and pressure than the saturated sample. Moreover, as for the DMSO sample, the fiber cell after a flow has destroyed in the intercellular layer, as shown in FIGS. 3-5, and it can be said that a cell length does not become short easily. Therefore, a DMSO sample can provide a molded article having excellent strength characteristics and toughness.

  The method for producing a fluid molded body of the present invention includes the type of solvent to be used, the molding temperature, the molding pressure, the moisture content of the raw material, and the properties of the molded body obtained by appropriately setting the molding time to predetermined conditions. Can be controlled with high accuracy. For example, by setting the temperature, pressure and time, and molding at low temperature, high load, and short time, the thermal decomposition of the molded body can be suppressed and the texture of the raw material can be reflected in the molded body. On the other hand, in molding at a high temperature, the material is thermally decomposed to some extent, so that the material can be softened and the load necessary for molding can be reduced.

The present invention has the following effects.
(1) It is possible to provide a method for efficiently producing a fluid molded body using a plant-based material as a raw material by a simple method.
(2) Whether the plant-based material before molding is a single bulk or separated into a plurality, it can be integrated in the molding process.
(3) The fiber orientation of the obtained molded product can be controlled by the arrangement of the plant-based material before molding in the mold.
(4) Strict moisture adjustment is not required when the plant material flows.
(5) Since the method for producing a fluid molded body of a plant material of the present invention uses a plant material that is a recyclable resource as a raw material, it is useful as a fundamental solution to resource problems and waste problems. It is.

  EXAMPLES Next, although this invention is demonstrated concretely based on an Example, this invention is not limited at all by the following Examples.

  A material having a diameter of 29 mm and a thickness of about 15 mm was cut out from the cedar sapwood part, and this was impregnated with DMSO (dimethyl sulfoxide) and then subjected to an experiment. For molding, a backward extrusion molding method using a mold composed of a stepped punch, a cylinder, and a spacer was used. In FIG. 1, an example of the shaping | molding method by back extrusion method is shown. One material was put into the cylinder, and it was deformed by pressurizing at 30 MPa with a stepped punch. Thereafter, the molded body was taken out from the mold to obtain a cup-shaped molded body. The time required for molding was about 1 minute. The obtained molded body was hardly discolored and kept the texture of cedar.

  The same sample as in Example 1 was used for the experiment. For the molding, a backward extrusion molding method using a mold composed of a stepped punch, a cylinder, and a spacer was used (FIG. 1). Two materials were put in the cylinder in a stacked manner, and were pressed and deformed by a stepped punch at 30 MPa. Thereafter, the molded body was taken out from the mold. The two materials were integrated to obtain a cup-shaped molded body. The time required for molding was about 1 minute. The obtained molded body was hardly discolored and kept the texture of cedar.

  A 30 mm square material was cut out from the cedar sapwood part, and a compression test was performed in the direction perpendicular to the fiber without pulverizing a wood sample that was completely dry, saturated, and impregnated with DMSO (dimethyl sulfoxide). went. The saturated wood sample had a low press pressure until the displacement reached 15 mm, but a sudden rise in pressure occurred when the displacement was around 20 mm. Also, the value was close to that of the completely dry state.

  This is considered to be due to the low reaction force only by compressing the cells up to 20 mm. If the displacement further proceeds beyond 20 mm when the compression is completed, the pressure of the saturated sample decreases. At this time, for the first time, the saturated sample begins to flow. On the other hand, the pressure of the DMSO sample has already started to increase when the displacement is 12 mm. This is because the pressure has increased because the flow has already started and the contact area between the sample and the mold has increased even though the consolidation has not been completed.

  The sample impregnated with DMSO started to flow with a smaller displacement and pressure compared to the saturated sample. FIG. 2 shows a pressure-displacement curve when a cypress material in a completely dry state, a saturated water state, and a dimethyl sulfoxide (DMSO) impregnated state is compressed in a direction perpendicular to the fiber. On the other hand, ethanol showed a higher pressure than water, and started to flow when the displacement was around 20 mm, as in the saturated sample. FIG. 3 shows a pressure-displacement curve obtained by adding the results of acetone and ethanol in addition to FIG. In addition, acetone caused splitting fracture without flowing (FIG. 3).

  After the end of flow, the fracture surface was observed by SEM. In FIG. 4, the SEM image of the torn surface after a flow is shown. In the sample in the completely dry state, the fiber cells are completely compressed by the compaction, and the cells appear to be broken in a form of tearing. Acetone also appears to be further compressed. On the other hand, in the DMSO-impregnated sample, cell compression has not progressed, and pits connecting the cells are clearly confirmed. This indicates that destruction has occurred between cells.

  As described above in detail, the present invention relates to a method for producing a fluid molded body of a plant material and the fluid molded body. According to the present invention, a plant system to which a solvent having hydrogen bonding ability is added and impregnated is provided. To fill and mold the material, pressurize and deform it to flow-fill into the mold, apply compressive force to compact the material, and create and provide a molded body with a complicated three-dimensional shape Can do. The present invention relates to a method for producing a fluid molded body of a plant-based material that can replace a plastic product made from petroleum as a raw material with a fluid molded body of a plant-based material that can cope with environmental and resource problems, and a product thereof. Useful for providing.

An example of the shaping | molding method of the shaping | molding process in this invention is shown. The pressure-displacement curve when a cypress material in a completely dry state, a saturated water state, and a dimethyl sulfoxide (DMSO) impregnated state is compressed in a direction perpendicular to the fiber is shown. The pressure-displacement curve which added the result of acetone and ethanol in addition to the cypress material of FIG. 2 is shown. It is a fracture surface after flowing, and shows an SEM image after flowing cypress in a completely dry state. It is a fracture surface after flowing, and shows an SEM image after flowing cypress swollen with acetone. It is a fracture surface after flowing, and shows an SEM image after flowing cypress swollen with dimethyl sulfoxide.

Claims (8)

  A plant-based material impregnated with a solvent having a small self-aggregation force and a hydrogen-bonding ability is placed in a mold, and pressure is applied at room temperature or under heating to change the mutual positional relationship of the constituent cells. A method for producing a fluid molded body of a plant-based material, characterized by forming a three-dimensional molded body by fluidly filling and molding it in a mold and applying compression to form a compact.   The method for producing a fluid molded body of a plant material according to claim 1, wherein the solvent having a small self-cohesive force and having a hydrogen bonding ability is dimethyl sulfoxide (DMSO) or dimethylformamide.   Plant material is put into a mold, the material is flowed and deformed, and the mold is flowed and filled, so that it is compacted by applying a compressive force of about 10 MPa to 300 MPa, and applied to a three-dimensional shaped compact. A method for producing a fluid molded body of a plant-based material according to claim 1 or 2, which is shaped.   The method for producing a fluid molded body of plant-based material according to any one of claims 1 to 3, wherein the plant-based material before molding is separated into a single or a plurality as a bulk and charged into a mold.   The method for producing a fluid molded body of a plant material according to any one of claims 1 to 4, wherein the fiber orientation of the resulting molded body is controlled by adjusting the arrangement of the plant material before molding in the mold. .   The plant system according to any one of claims 1 to 5, wherein in the molding process, the molding temperature and / or the molding pressure is controlled to suppress thermal decomposition of the molded body and reflect the texture of the raw material in the molded body. A method for producing a fluid molded body of material.   The method for producing a fluid molded body of a plant material according to any one of claims 1 to 6, wherein the plant material is wood, bamboo, vegetation, or agricultural waste.   A molded product having a deep bottom shape produced by the method according to any one of claims 1 to 7, wherein the molded product is a compression molded product of 1) dimethyl sulfoxide (DMSO) or dimethylformamide-impregnated wood. A fluid molded body of a plant-based material, wherein the texture is reflected in the molded body, and 3) has a cup-like deep bottom structure.