JP4154305B2 - WOODEN MOLDED ARTICLE AND METHOD FOR PRODUCING WOODEN MOLDED ARTICLE - Google Patents

Description

  The present invention relates to a molded body using a wooden material and a method for manufacturing the same, and more particularly to a wooden molded body suitable for use in contact with human skin and a method for manufacturing the same.

  As a substitute for petroleum resources, or as a substitute for solid wood, wood molding, which is made of wood, grass leaves, stems or husks of shells, etc., formed into small pieces such as chips, flakes, fibers, etc. There is a body. The woody molded body can be used as a base material for installing interior materials such as trims and panels of vehicles and buildings, tiles, interior panels, and the like. For wood molded products, strength, rigidity, sound insulation, water resistance, heat resistance, surface, etc. are devised according to the application, such as the material type, shape, binder type and blending ratio, and pressure conditions. Desirable numerical values have been achieved in various properties such as coefficient of friction, smoothness, and color. (For example, see Patent Documents 1 and 2.)

JP 2002-86421 A Japanese Patent Laid-Open No. 7-40314

  In the woody molded body, for example, when light weight and high strength are to be achieved, it is considered that the surface side is formed to be harder and the inside has a low density. In this case, it is preferable that the surface side is typically denser, that is, a piece of wood material is compressed and less compressed internally. However, since the low specific gravity small piece material is generally weaker than the high specific gravity small piece material, the low specific gravity small piece material and the high specific gravity small piece material are laminated and added simultaneously. When pressure molding is performed, a uniform compressive force is applied to the whole, and a molded body having a small density difference is often obtained as a whole. In addition, for example, in the case of imparting heat insulation properties, it is preferable to keep the structure of the wood material and keep the gap held by the structure, but for strength, rigidity and surface hardness, it is smooth. A dense construction is preferred, for which the wood material has to be compressed. Such a molded body having portions with different degrees of compression in the thickness direction has a method in which each portion is formed by pressure molding and then bonded, but this takes time.

Therefore, an object of the present invention is to provide a method for manufacturing a woody molded body in which a low compression portion and a high compression portion are pressure-molded simultaneously. Thereby, for example, a method for producing a woody molded body having a high surface hardness and a small surface heat flux is provided.
Another object of the present invention is to provide a wood molded body in which a low density portion and a high density portion are simultaneously molded. Thereby, for example, a woody molded body having a high surface hardness and a small surface heat flux is provided.

The first invention of the present invention for solving the above-mentioned problems is that a woody material derived from herbs or a woody material having a density of 0.3 g / cm ³ or less is mechanically destroyed in a dried state after being collected. A low compression layer in which the pieces are assembled so that the fibers in the pieces are regularly arranged, and a piece of wood material and a binder resin. A pre-molding laminate having a high compression layer in which small pieces of material are gathered so that the fibers in the small piece material are irregular rather than the low compression layer, It is a manufacturing method of the wooden molded object provided with a density part.
In the second invention, the small piece material of the low compression layer is a thin piece material that is long in the fiber running direction, and the thin piece material is assembled in parallel to the low compression layer and adjacent to the low compression layer. And a method for producing a woody molded body in which a pre-molding laminate having a high compression layer forming a surface is heated and pressed.
Further, the third invention is the second invention, wherein a high compression layer is provided at the center of the pre-molding laminate and subjected to heat and pressure molding, and then at least the surface high compression layer is removed to form the central high compression layer. This is a method for producing a woody molded body for producing a thin portion.

Moreover, the 4th invention of this invention is provided with the surface part to which the small piece material of the wood material was couple | bonded with the binder in the compression state, and the wood material or wood book which was provided adjacent to the said surface part, and originated from herbs In a state in which the wood material having a density of 0.3 g / cm ³ or less is mechanically destroyed in a state after being dried after being collected, the small pieces formed by the binder are assembled so that the fibers are regularly arranged. It is a woody molded object provided with the low-density part couple | bonded.
Further, the fifth invention is a woody molded body having an overall average density of 0.7 g / cm ³ or less.
A sixth aspect of the present invention is the woody molded body according to any one of the above, wherein the small piece material constituting the low density portion is formed into a thin piece material that is long along the longitudinal direction of the fiber, and the surface portion, the low density portion, It is the woody molded object assembled so that it may extend in parallel with the boundary surface.
A seventh aspect of the present invention is any one of the above wood molded articles, comprising a front portion and a low density portion from both surfaces toward the inside, wherein a small piece of wood material is between the low density portions on both sides. The core is a wood molded body that is joined by a binder in a compressed state and has a higher density core than the low density portion, and that forms a projecting portion that protrudes in the thickness surface of the wood molded body.

ADVANTAGE OF THE INVENTION According to this invention, the wooden molded object which has a part from which a density differs can be obtained easily by providing the manufacturing method of the wooden molded object which press-molds a low compression part and a high compression part simultaneously. In addition, by providing the wood molded body and the wood molded body in which the low density portion and the high density portion are simultaneously molded, a wood molded body having various functions can be easily obtained. Furthermore, the wooden molded object which can be utilized favorably for the site | part which contacts human skin can be supplied. For example, by producing a wood molded body by providing a high compression portion on the surface and a low compression portion on the inside thereof, the wood having a high density portion on the surface and having a low density portion adjacent to the high density portion A molded body can be produced. In such a wooden molded body, the surface retains higher strength, hardness, etc., and heat transfer to the inside of the wooden molded body is suppressed by the low density portion, and the heat flux of the surface is reduced. It becomes a molded body.
In particular, according to the method for producing a woody molded body of the first invention, a woody material derived from herbs or a woody material having a density of 0.3 g / cm ³ or less mechanically in a state of being dried after being collected. The broken piece material has a low density, and the low compression layer assembled so that the fibers in the small piece material are regularly arranged has the fibers arranged more irregularly than the low compression layer. High compression strength than the high compression layer. For this reason, even if the whole pre-molded body including the high compression layer and the low compression layer is heated and pressed at a constant pressure, the low compression layer can maintain a low density satisfactorily. Therefore, it is possible to manufacture a wood molded body having a low density portion and a high density portion by a simple method.
In this specification, “0.3 g / cm ³ or less” for the wood material is not limited to a material that is 0.3 g / cm ³ or less in the state of a thin piece material, and appropriately treats the wood material after sampling. In addition, a material having an apparent density of 0.3 g / cm ³ in a dry state is also included. For example, for a material obtained in a state having a hollow portion such as a tube, the apparent density including the volume of the hollow portion may be 0.3 g / cm ³ or less.

Moreover, according to the manufacturing method of the wooden molded object of 2nd invention, since the low compression layer has the flake material long in the fiber direction gathered in parallel with the layer, it gives bending strength to the obtained wooden molded object. be able to. The flake material is preferably arranged so as to extend in an arbitrary direction in a direction parallel to the layer, whereby the bending strength in any direction can be improved. By providing a high compression layer constituting the surface adjacent to the low compression layer, the strength of the surface, that is, the hardness can be maintained. Therefore, it is possible to produce a wood molded body that prevents weight increase, has high surface hardness, and good bending strength. In this case, if the high density portion formed by the high compression layer constituting the surface is sufficiently thin, for example, 2 mm or less, the high density of the surface that is insulated from the center portion of the wooden molded body by the low density portion. The heat flux in the density part is significantly reduced. Therefore, it is possible to obtain a woody molded body that has a small surface heat flux and hardly feels a temperature difference.
According to the manufacturing method of the third aspect of the invention, by controlling the thickness of the central high compression layer, the characteristics formed by the high compression layer and the low compression layer on the surface can be maintained, and the strength is good at the desired thickness. Can be produced. In addition, since the central high-compression layer is molded at a high density, it maintains a good strength. Therefore, the high-density portion formed by the surface high-compression layer may be removed to provide a thin portion having a good strength. it can.

Further, in the woody molded body of the fourth invention of the present invention, the surface part is provided adjacent to the surface part as a small piece of wood material is bonded in a compressed state and has high strength and high hardness. The low density part reduces the heat transferability with the inside of the wooden molded body, and the heat flux is reduced. Therefore, it is a woody molded body that is not easily damaged and that does not feel a temperature difference even when touched.
In the fifth invention, since the average density of the entire molded body is 0.7 g / cm ³ or less, it is lightweight.
In the sixth invention, since the fibers extend in parallel with the low density portion in the low density portion, the wood molded body has a higher bending strength.
In the seventh aspect of the invention, the wood molded body is further provided with a core portion having a density higher than that of the low density portion at the center in the thickness direction of the wood molded body, and a projecting portion projecting on the thickness surface of the wood molded body is formed by the core portion. ing. Therefore, it is a wooden molded body in which the heat flux of the front portion is small and the strength of the protruding portion is ensured.

The best mode for carrying out the present invention will be described below with reference to the drawings.
1 and 2 show a woody molded body 1 according to an embodiment of the present invention. The woody molded body 1 is a panel that can be used as an indoor flooring, and is formed in a square plate shape. Further, the wooden molded body 1 is connected to the same adjacent wooden molded body 1 so that it can be connected in the same plane. And a mezzanine portion 4 formed in a groove shape on the thickness surface of the side. The OZane part 3 corresponds to the protruding part and the thin part in the present invention.

The woody molded body 1 includes front portions 11 on both surfaces, and low density portions 13 are provided adjacent to the front portion 11.
The front portion 11 is composed of a small piece of wood material 11a and a binder, and the small piece of wood material 11a is in a compressed state. The small piece of wood material is made of various wood materials derived from woods and herbs, and is formed into powder, granules, fibers, chips, flakes, and the like. Here, woody materials derived from trees and herbs include wood and bark, palm husks, sisal, rice, jute, kenaf, and other plants collected from various trees such as conifers, broadleaf trees, and tropical trees. For example, bast plants. Moreover, the material processed chemically appropriately, such as sugarcane bagasse and pulp, may be used. For example, it may be formed in a fiber mat shape. The small piece material 11a constituting the surface portion 11 is selected in consideration of the property to be applied to the surface portion 11, the surface color to be applied, and the like. When it is desired to obtain the high-density surface portion 11, a shape having a small diameter such as a granular shape or a powder shape, a shape such as a chip shape that can be easily deformed and easily formed into a dense state by compression is preferable. Further, when it is desired to color the surface of the wooden molded body 1 or to form a whitish color, for example, it is preferable to use a kenaf core (core material) or basara. It is preferable to use a core.
In addition, when the same material as the small piece material 13a included in the low-density portion 13 described later is used, the material type necessary for creating the wooden molded body 1 can be reduced, and the specific gravity is lighter and stronger. Since the high surface part 11 is easy to be formed, it is preferable.

  The binder of the front portion 11 is made of a known binder resin that can hold the small pieces 11a in a compressed state to each other and hold them in a plate shape. Although it may be a thermoplastic resin, typically, it is a thermosetting resin, and if it is a urea resin, a melamine resin, a phenol resin, a urethane resin, etc., the surface part 11 with higher heat resistance and strength is easily formed, preferable. Further, it may be an adhesive material derived from a wood material such as lignin in wood. The ratio of the binder resin to the small piece material 11a is not particularly limited, but the small piece material: binder resin can be 9.5: 0.5 or more and 5: 5 or less in the weight ratio. When the binder resin is less than 0.5%, the small pieces are not sufficiently bonded, and the surface easily breaks. Moreover, when binder resin exceeds 50%, specific gravity will become large and the low heat transferability originating in a woody material will be lost. Preferably, the weight ratio of the small piece material: binder resin is 9.5: 0.5 or more and 7: 3 or less, and more preferably, the weight ratio of the small piece material: binder resin is 9.2: 0.8 or more. When the ratio is 8: 2 or less, it is easy to obtain the surface portion 11 having good strength and rigidity, light weight, and reduced heat transfer properties.

  The low density portion 13 is a layer formed at a lower density than the surface portion 11 and contains a small piece 13a of wood material and a binder resin. In the low density portion 13, the small piece material 13 a is not compressed more than the small piece material 11 a of the front portion 11. That is, the wood material retains more of the low-density structure that the natural material possessed in nature, and the overall density is low.

The small piece material 13a in the low density portion 13 is selected from a lower density wood material, that is, a wood material having a low density in a natural state, that is, an uncompressed state. In general, a woody material collected from herbs is preferable because it has a lower density than a material derived from general woods. A small piece shape obtained by mechanically destroying a woody material having a density of 0.3 g / cm ³ or less in a dried state after collection is also suitable. Specific examples include cores of bast plants such as kenaf, sisal, and jute, and particularly low-density trees such as cedar and basara. Herbs are preferable because they can be cultivated, and it is easy to obtain a woody material in a dried state after collection, especially a core having an apparent density of 0.3 g / cm ³ or less. Particularly, kenaf core, which is an annual grass, is preferable because it can obtain a wood material of 0.3 g / cm ³ or less on average.

The shape of the small piece material 13 a is a shape that is easily arranged regularly in the low density portion 13. Examples of such shapes include shapes that can be easily aligned, such as flakes, strips, and blocks, that is, shapes that can form a relatively dense filling state without being compressed. The thin piece material is preferably arranged regularly and easily, for example, by deposition.
In addition, in this specification, a thin piece material shall mean the material which has the thickness which can maintain a flat shape, for example in the state mounted in the plane. For example, a very thin thin-skinned or film-like material that is wound like sawdust is flexible, so it is difficult to form a regular array, and it does not have the low-density structure inherent to woody materials. The density of the low density portion 13 tends to be high.

  The flake material can be formed with a cutter or an abrasive. If the flake material is formed longer, a regular arrangement is likely to be formed, and for example, the average length is preferably 100 mm or more. Further, preferably, the small piece material 13a contains longer fibers, or if the fiber arrangement in the natural state substantially parallel to each other is kept longer, the wood molded body 1 can be given bending strength. it can. Therefore, the flake material preferably has an array of fibers extending along the longitudinal direction. Therefore, when the small piece material 13a is a thin piece material, it is a thin piece material containing fibers extending along the surface direction of the thin pieces, and more preferably containing fibers extending along the longitudinal direction of the thin pieces.

  In addition, since the thin piece material containing the fiber extended along the thickness direction of a thin piece material has high compressibility in the thickness direction, it is easy to obtain the low density part 13 of a lower density. For example, as a low density portion 13, a layer made of a flake material having fibers along the longitudinal direction and a layer made of a flake material having fibers along the thickness direction may be provided.

  The binder which comprises the low density part 13 is binder resin similar to the binder of the surface part 11, and is not specifically limited. Moreover, it is preferable that the binder resin is the same as that of the surface part 11 because the number of materials is reduced and the surface part 11 and the low density part 13 are well bonded to each other. In the low density portion 13, the weight ratio between the small piece material 13a and the binder can be in the range of 9.5: 0.5 or more and 5: 5 or less. If the binder is less than 0.5%, the small piece material 13a, particularly the thin piece material 13a, is difficult to bond well, and if it exceeds 50%, the density due to the binder increases, and the density is sufficiently low. Don't be. Preferably, it is 9.5: 0.5 or more and 7: 3 or less, More preferably, it is 9.2: 0.8 or more and 8: 2 or less.

  As shown in FIG. 2, the wood molded body 1 is formed by a core portion 15 at the center. The core 15 includes a small piece of wood material and a binder resin. The small piece material and the binder resin of the core portion 15 can be selected from the small piece material and the binder resin as described in the front portion 11, respectively, and thus description thereof is omitted. The core portion 15 may be formed of the same material as the front portion 11 or may be formed from a different material, for example, the shape, size, material, or binder resin type of the small piece material, or the weight of the small piece material. At least one of the ratios may be different. The core portion 15 is formed at a higher density than the low density portion 13. Therefore, generally, the rigidity and strength are higher than those of the low density portion 13.

Of course, the surface part 11, the low density part 13, and the core part 15 may contain other additives as appropriate. Examples of the additive include a well-known additive provided for the binder resin, a dispersant for preserving the binder resin more uniformly on the wood material, a preservative, and a colorant.
In particular, the front portion 11 may be printed in order to give a color and a pattern. In addition, in order to give antifouling property, a color, a pattern, luster, etc. to the surface, although coating may be given, in order to utilize the smaller heat flux of the surface part 11, it becomes the object of heat transfer. It is preferable that a foot or the like is in direct contact with the front portion 11.

  The ridge part 3 and the mezzanine part 4 of the wood molded body 1 are formed by a core part 15. The ozone part 3 and the mezzanine part 4 are formed in sizes and shapes that fit each other, and are parts that connect a plurality of woody molded bodies 1 in the same plane. The Ozone part 3 is preferable because it is hard and has good strength when formed in an arbitrary thickness within the thickness of the core part 15 in the thickness direction. On the other hand, since the low density portion 13 is easily crushed at a low density, in order to compensate for the clearance between the ridge portion 3 and the mezzanine portion 4, at least one surface of the ridge portion 3 and / or the mezzanine portion 4 is formed on the low density portion 13. It may be formed by.

  The wood molded body 1 has desired strength and rigidity obtained by a small piece of wood material by the core portion 15 and the surface portion 11, and the heat flux at the surface portion 11 is reduced by the low density portion 13. Therefore, it is a woody molded body which does not increase in weight or is reduced in weight and has a small heat flux and hardly senses a temperature difference. Moreover, since the anti-compression material of the low density part 13 is comprised from the thin piece material long along the fiber, compared with the wooden molded object 1 using only a chip | tip etc., bending strength is high. Therefore, it is also suitable for use at sites that require deflection.

  In the woody molded body 1, it is particularly preferable that the low-density portion 13 has a lower density because the surface heat flux is favorably reduced. Furthermore, in addition to such a low density portion 13, it is more preferable that the thickness of the surface portion 11 is thinner because the surface heat flux is reduced more favorably.

Next, the manufacturing method of the wooden molded body according to the present invention will be described by taking the case of manufacturing the wooden molded body 1 as an example.
First, the high compression layer made of the raw material of the surface portion 11, the low compression layer made of the raw material of the low density portion 13, and the high compression layer made of the raw material of the core portion 15 are in the order shown in FIGS. A pre-molding laminated body laminated on the substrate is prepared. The laminate before molding may be prepared so as to maintain a predetermined shape, or may be directly deposited on a press die for molding. For example, the raw material of the front part 11, the raw material of the low density part 13, the raw material of the core part 15, the raw material of the core part 15, and the low density part 13 in the pre-molding laminate forming means formed by the bottom plate and the rectangular frame forming each side plate It is possible to create a pre-molding laminate by depositing each material with a predetermined basis weight in the order of the raw material and the raw material of the surface portion 11.

  Here, the raw material of the high compression layer and the low compression layer contains at least the woody material forming the surface portion 11 or the low density portion 13 as described above. The binder resin raw material used as the binder may be added to each wood material in advance, or may be applied after each wood material is deposited with a predetermined basis weight to form a high compression layer or a low compression layer. If it is, you may give from the surface after producing the laminated body before shaping | molding. The binder resin material is typically dissolved in a solvent or dispersed in a dispersion medium to prepare a liquid, and a small piece of wood material is immersed in a binder resin bath, or a known coating method such as spraying or roller. It can be added by coating with. In addition, when adjusting the ratio of binder resin small, application | coating is preferable.

  In the pre-molding laminate, the low compression layer small pieces are assembled so that the fibers in the small pieces are regularly arranged. For example, in a block-shaped small piece material, it arranges so that each surface may be in surface contact. In the case of a flake material, since it becomes substantially horizontal by depositing using gravity, it can be easily arranged regularly and assembled. Also, when arranging the fibers parallel to the layers, if you want to increase the bending strength in a given direction, place the flake material so that the fibers are perpendicular to the bending direction, and increase the overall bending strength. If desired, it is preferable to dispose the flake material in an arbitrary direction parallel to the surface. Alternatively, the low compression layer is not limited to a single layer, and may be a plurality of layers arranged with different regularity. For example, a layer in which fibers are arranged in parallel to the direction of the low compression layer and a layer in which fibers are arranged perpendicular to the direction of the low compression layer can be provided. Alternatively, it is possible to provide a layer parallel to the direction of the low compression layer and arranged in one direction at right angles or different angles.

  The pieces in the high compression layer are gathered so that the fibers in the piece are more irregular than the pieces in the low compression layer. For example, by forming the small piece material into a shape having a non-uniform shape or a complicated three-dimensional shape, the small piece material is gathered in a state where the fibers are directed in various directions by being deposited using gravity. A preferable shape of the small piece material for such a method is a chip shape, an irregular granular shape or the like. Or when selecting a thin piece material as a high compression layer, it is set as the thin piece material smaller than the small piece material of a low compression layer. The fiber mat or the like can be used as it is because the fiber direction is irregular when it is formed on the mat.

  Next, this laminate before molding is pressure-molded in a heated state. The pressure molding method is the same as in the case of a known wooden molded body. The pre-molding laminate containing a thermosetting resin as the binder resin is pressed with a press mold that has been heated to a temperature equal to or higher than the curing temperature of the binder resin in advance, and is cooled to the curing temperature, and then cooled. Let At this time, the pressurizing condition can be selected as appropriate, but the small compression material of the high compression layer is compressed and the small compression material of the low compression layer is not compressed more than the small compression material of the high compression layer. For example, when a thin piece material long in the fiber direction of the kenaf core is used as the low compression layer, the pressure is well maintained in a low density state when the pressure is in the range of 1.0 MPa to 5.0 MPa. Therefore, it is preferable.

  In the laminate before molding, in the low compression layer, the fibers are arranged more regularly and are not easily crushed. For this reason, the low compression layer maintains a low density state. Further, in the low compression layer, an anti-compression force is generated in the layer direction, so that a slightly large compression force is applied to the high compression layer constituting the surface and a good high density state is obtained. Thereby, the wooden molded object provided with a high compression part and a low compression part is obtained by the same heat-pressure shaping | molding as the past.

  When a thermoplastic resin is used as the binder resin, the entire laminate before molding is heated to a predetermined temperature, and then molded into a predetermined shape and thickness by a known method of pressing with a normal temperature press die. be able to.

Thereafter, it is appropriately adjusted to a predetermined shape using a known cutting means or the like. In the case of manufacturing the woody molded body 1, next, the ozone part 3 and the mezzanine part 4 are created.
In the creation of the Ozone part 3, the front part 11 (high compression layer), the low density part 13 (low compression layer), and the core part 15 (as appropriate) with a predetermined width along two adjacent edges of the wooden molded body 1 The central high compression layer) is removed by cutting with a known cutting means. Since the core portion 15 (the central high compression layer) that is exposed by this is a portion compressed higher, the Ozone portion 3 has high rigidity and high strength.
On the other hand, in the creation of the mezzanine portion 4, a concave groove having a size that allows insertion of the ozone portion 3 along the two end edges where the ozone portion 3 is not formed is created on the thickness surface. Specifically, it can be created by removing the core portion 15 (central high compression layer) and the low density portion 13 (low compression layer) as appropriate.

In the present invention, for example, a wood material having a density of 0.3 g / cm ³ or less, for example, a kenaf core, is used for the entire surface layer, low density layer, and core layer, and the binder resin is 10% of the weight of the wood material in each. (Weight ratio of woody material: binder resin is 9: 1) and heated and pressure-molded to obtain an average density of 0.7 g / cm ³ or less and a bending strength of 10 Mpa or more. A molded body can be obtained. Such a wooden molded body has a small heat flux, makes it difficult to feel a temperature difference, and is lighter than a general plywood or resin board. For this reason, it is suitable for flooring. In addition, in FIG. 3, the result of having measured the time change of the heat flux (a) of the surface in this wooden molded object and the heat flux (b) of the surface of the wooden molded object of the same thickness which does not have a low density part is shown. Show. As shown in FIG. 3, since the heat flux becomes smaller sooner after the maximum of the heat flux that appears within 1 second immediately after contact, it is difficult to feel a temperature difference for a short time after contact, for example, a foot during walking. That is, when the flooring is cold, it does not feel too cold, and when the flooring is warmed, it does not feel too hot.

In addition, this invention is not limited to the said embodiment.
The wooden molded body is not limited to a floor material, and may be an inner wall material, a ceiling material, a furniture decorative material, or the like. Alternatively, indoor floor materials, inner wall materials, and ceiling materials such as vehicles and ships may be used. Among the woody molded bodies, a type having a small surface heat flux is particularly suitable for a portion that touches human skin. Therefore, for example, by adding water resistance, it is also preferable to apply to a part such as a washroom, a bathroom, a sauna, a dressing room, etc., walking with bare feet or sitting on the floor. In the woody molded body 1 of the present embodiment, the surface portion and the low density portion are provided on both surfaces, but it is needless to say that a configuration relating to only one surface may be provided.

  Moreover, in the manufacturing method of the wooden molded object which concerns on this invention, it is not limited to the manufacturing method of a wooden molded object provided with a high compression part in a front part, and a low compression part adjacent to a front part, Various density gradients are provided. A woody molded body can be produced. For example, it is possible to obtain a wood molded body having a low compression portion in the front portion and a high compression portion inside so that the surface is soft and smooth. Also, a plurality of different types of low compression layers may be provided.

It is a perspective view which shows one Embodiment of the wooden molded object of this invention. It is the elements on larger scale of the woody molded object of FIG. It is a graph which shows the time-dependent change of the heat flux of the wooden molded object which concerns on one embodiment of this invention, and a conventional product.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wood molded object 3 Ozone part 4 Mezzanine part 11 Front part 13 Low density part 15 Core part

Claims (4)

Containing a small piece of material obtained by mechanically destroying a woody material having a density of 0.3 g / cm ³ or less and a binder resin in a state where the woody material derived from herbs or the woody material is dried after being collected, A low compression layer in which the small pieces are assembled so that the fibers in the small pieces are regularly arranged;
A pre-molding laminate comprising a small piece of wood material and a binder resin, and a high compression layer in which the small pieces are gathered so that fibers in the small piece material are irregular rather than the low compression layer. In the production of a wooden molded body having a low density part ,
The small piece material of the low compression layer is made into a thin piece material that is long in the fiber running direction, and the thin piece material is assembled in parallel to the low compression layer and the surface is formed adjacent to the low compression layer. After forming a high compression layer in the center of the pre-molding laminate comprising heat and pressure molding, at least remove the high compression layer on the surface to create a thin part composed of the central high compression layer , Manufacturing method. A surface part in which small pieces of wood material are joined together by a binder in a compressed state;
A density of 0.3 g / cm in a state where the woody material or woody material derived from the herbs is dried after being collected, provided adjacent to the surface part. ^Three A low density portion in which small pieces formed by mechanically destroying the following wood material are joined together by a binder in a state where the fibers are assembled so that the fibers are regularly arranged;
With both surfaces inside,
Between the low-density parts on both sides, a small piece of wood material is bonded by a binder in a compressed state, and has a core part with a higher density than the low-density part,
The core portion is a wood molded body that forms a protruding portion that projects in the thickness surface of the wood molded body. The woody molded product according to claim 2, wherein the overall average density is 0.7 g / cm ³ or less . The small piece material constituting the low density portion is formed into a thin piece material that is long along the longitudinal direction of the fiber, and is assembled so as to extend in parallel with the boundary surface between the surface portion and the low density portion. 2. A woody molded article according to 2 or 3 .

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