JP2006082353A - Woody thermoplastic resin composition and method for producing woody thermoplastic resin molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding method using a woody thermoplastic resin composite for a molding, for example a wide building material with surface waving or twisting suppressed molded by a simple press molding method, which maintains surface properties and warmth specific to a woody raw material and the woody thermoplastic resin composite for obtaining the molding. <P>SOLUTION: A thermoplastic resin composition comprising 30-80 wt.% of the woody raw material containing at least 20 wt.% of crushed wood chips at least 1 mm in thickness or width, below 10 mm in length, and below 3 in aspect ratio and 20-70 wt.% of a thermoplastic resin is charged in a mixing container equipped with agitation blades. Agitation is continued until the resin is melted by frictional heat by agitation and mixed with the woody raw material to form a molten mixture. The molten mixture is charged in a press mold and cooled while being pressurized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a composite of a wood thermoplastic resin obtained by mixing a wood-based material and a thermoplastic resin, and a method for molding a molded product obtained by melting and pressing the wood thermoplastic resin composite. The obtained molded product can be used for various panel-shaped building materials and the like.

  Conventionally, a mixture of woody raw materials such as fine powdery wood powder and thermoplastic resin is the best, and this is molded using an extruder, so that it can be used as a peripheral edge in houses and various decks. Many materials are used as long building materials.

  For example, a method is known in which a wood-based raw material having a long side of 1 to 10 mm is mixed with a thermoplastic resin to be pelletized, and the pellet is molded with an extruder (see, for example, Patent Document 1).

  However, in the method of Patent Document 1, the thermoplastic resin is filled into the cell wall of the wood-based raw material at the time of pelletization, and at the time of extrusion molding, the nozzle is clogged, or the shrinkage ratio of the wooden raw material and the thermoplastic resin is reduced. There is a problem that a fine powdery woody raw material has to be used for the reason that the product is twisted due to the difference.

  In addition, because it passes through a high-temperature mold, a thermoplastic resin skin layer is formed on the surface of the resulting molded body, and the wood-based raw material is completely covered with resin, so that the feel and warmth inherent to wood are lost. There's a problem. Further, if secondary processing such as polishing or decorating the surface is performed in order to improve the touch or the like, the processing cost is high and the product tends to be expensive.

  Furthermore, to obtain a wide molded body, it is necessary to increase the capacity of the extruder. Due to the difference in shrinkage between the wood-based raw material and the thermoplastic resin, the surface of the resulting molded product is increasingly wavy and twisted. There is a problem that it is easy to occur and uniform molding is difficult.

  Separately, wooden boards such as particle board, OSB (Oriented Strand Board), MDF (Medium Density Fiber Board) using wood-based raw materials and thermosetting resin, or LSL (Laminated Strand Wood-based materials that can be used as structural materials such as lumbar) and PSL (parallel strand lumbar) are generally distributed and used in various applications. There is a problem that there is.

  As a method for obtaining a molded article having a different diameter, there is a method in which a thermoplastic resin and a wood piece are put into a mixer having blades rotating at high speed and stirred, melted by frictional heat, a molten mixture is taken out and press-molded. It is known (for example, refer to Patent Document 2).

According to the method of Patent Document 2, it is not necessary to perform a pre-process such as pre-drying of the thermoplastic resin and the wood pieces, and it is possible to perform atypical molding without using the wood-based raw material as a fine powder. However, even in this method, there is a problem that the wood pieces are divided by the high-speed rotating blades, the wood pieces are substantially powdered in the molten mixture, and the wood-based raw material is also covered with the resin.
JP 2003-291116 A JP-A-11-226956

  The present invention is capable of forming a molded product such as a wide building material with less undulation and twisting on the surface by a simple press molding method, and the obtained molded product maintains the surface property and warmth inherent to the woody material. The object of the present invention is to provide a molding method of a molded article using a thermoplastic resin composite and a woody thermoplastic resin composite for obtaining the molded article.

  The woody thermoplastic resin composition (Invention 1) according to claim 1, wherein the woody raw material contains 20% by weight or more of crushed wood chips having a thickness or width of 1 mm or more, a length of less than 10 mm and an aspect ratio of less than 3. It consists of 30 to 80% by weight and 20 to 70% by weight of thermoplastic resin.

  The method for producing a wooden thermoplastic resin molded body according to claim 2 (invention 2) is characterized in that the wooden thermoplastic resin composite is put into a mixing container provided with a plurality of stirring blades, and the thermoplastic resin is friction caused by stirring. It is melted by heat, stirred until the thermoplastic resin and the wood-based raw material are mixed to form a molten mixture, and the molten mixture is put into a press mold and cooled while being pressurized.

  The invention according to claim 3 (invention 3) is that, in the molten mixture after being put into the press mold, the distribution of wood crushing chips in the molten mixture is distributed more on the surface than inside, and the wood crushing It is a manufacturing method of the woody thermoplastic resin molding of the invention 2 characterized in that the chip is exposed on the surface.

  In the invention according to claim 4 (invention 4), the mixing container has a clearance in which the wood crushing chip can move between the stirring blade and the inner surface of the container, and the number of rotations of the stirring blade is 3000 to 3000. It is a manufacturing method of the woody thermoplastic resin molding of the invention 2 or 3 characterized by being 6000 rpm.

  The tree species of the wood-based material used in the inventions 1 to 4 is not particularly limited as long as it is a general-purpose architectural or structural wood-based material. For example, conifers such as cedar, cypress, spruce, fur, radiatapine, etc .; broadleaf trees such as birch, apton, chamelere, sengonlaut, aspen, etc., but not only plant materials produced from these forests, , Plant materials produced outside the forest, such as Kouliang, can also be included.

  Forms that can be used as wood-based raw materials are not particularly limited, but, for example, logs of the above-mentioned tree species, raw materials such as thinned wood, scraps generated at factories and residential construction sites, waste pallet materials discarded after transportation of materials, building dismantling Arbitrary woody materials such as dismantling waste materials and waste materials such as distribution packing materials that are sometimes generated can be used as raw materials (hereinafter referred to as woody materials) in combination of one or several kinds.

  In the invention 1, the wood-based raw material is in the range of 30% by weight to 80% by weight in all raw materials. The mixing ratio (parts by mass) of the wood-based raw material and the thermoplastic resin is preferably 30:70 to 80:20, more preferably 40:60 to 70:30, and still more preferably 50:50 to 60:40.

  If the ratio of the wood-based material exceeds 80% by weight, mutual dispersion becomes difficult during melt mixing, and the thermoplastic resin does not physically bond with the wood-based material, making it easy to nest into the molded product, resulting in poor moldability. There are things to do. If the ratio of the wood-based material is less than 30% by weight, the thermoplastic resin is completely filled in the holes of the temporary conduit of the wood-based material, and the characteristics of the porous wood-based material are lost. There is a problem that the feel of the obtained molded product is deteriorated, and it is difficult to obtain a sufficient wood texture. Therefore, it is preferable to appropriately adjust the supply amount so that the mixing ratio is within the above range.

  The woody raw material in the raw material contains 20% by weight or more of crushed wood chips having a thickness or width of 1 mm or more, a length of less than 10 mm, and an aspect ratio of less than 3. If the width or thickness is less than 1 mm, the wood crushing chips may be broken by collision and subdivided when the thermoplastic resin is melted by the stirring blades. Molding is possible even if the length is greater than 10 mm, but if it is too large, irregularities are conspicuous on the surface of the molded product, and the appearance may be deteriorated. In order not to apply a large load to the stirrer when the mixture is made into a molten mixture, it is preferably less than 10 mm.

  If the aspect ratio is 3 or more, the thermoplastic resin is unevenly covered on the surface of the wood-based raw material, and there is a risk that the appearance and the feel of wood will be lost. In addition, the chance of collision between the wood crushing tip and the stirring blade increases, and the thickness or width of the wood crushing tip becomes 1 mm or less. The risk of being less than 20% by weight increases.

  Moreover, when the crushing chip | tip of the said dimension is less than 20 weight% in a wood type raw material, the fault that the molded article obtained will lose the touch peculiar to a wood type raw material will come out.

  Thus, the crushed wood chip in the wood-based material is preferably 20% by weight or more, more preferably 30% by weight or more, and further preferably 45% by weight or more, as long as the width or thickness is 1 mm or more. The remainder may be made of a woody material having a width or thickness of less than 1 mm. In this case, the remaining woody material may have a length of 10 mm or more or an aspect ratio of more than 3.

  As a method of obtaining the above-mentioned wood-based raw material, a method of cutting wood into a stick by cutting veneered wood with a hammer mill or rotary cutter into a chopsticks shape, cutting a log with a flaker rotary blade and strand And a method of crushing a wood-based material by rotating a roll with a blade on the surface of a uniaxial crusher.

  And generally, the thickness and length of the wood-based raw material crushed as described above are uneven. Accordingly, the wood-based raw material is classified and adjusted in size so that 20% by weight or more of wood crushing chips having a width or thickness of 1 mm to 10 mm and an aspect ratio of less than 3 are contained. The classification method is not particularly limited as long as it can be classified with a certain range of thickness and length. For example, a classification method using a classifier such as a wave roller system, which is a device that classifies continuously based on the thickness of the chip, a method using a sieve with a predetermined opening, and the like can be given.

  For example, the raw material of wood is roughly pulverized to a few centimeters with a jaw crusher or gylen tri-crusher, then introduced into a hammer mill, cutter mill, roll mill, etc., and pulverized to a width or thickness of several millimeters. The obtained finely pulverized needle-shaped product is passed through a sieve having an opening of 7 mm to remove the wood pieces having a longer side of more than 10 mm, and further passed through a sieve having an opening of 0.7 mm to remove the woody raw material having a longer side of less than 1 mm, You may make it the average size of a wood type raw material become in the range of 1 mm-10 mm. If it does in this way, the wood-type raw material whose 20 weight% in a wood-type raw material is a wood crushing chip | tip of 1 mm-10 mm is obtained.

  The aspect ratio of the individual fragments of the woody material obtained by the type and moisture content of the woody raw material, or the coarse and fine pulverization methods varies. Therefore, when the content of the wood crushing chips having an aspect ratio of less than 3 in the wood-based material obtained by the above method is less than 20% by weight, the opening of the sieve to be used is changed to change the amount of the wood-based material. A general method such as a method of changing the size, a shape of a hammer or blade in a crusher, a method of adjusting the clearance between the chamber and the hammer, or the blade may be used.

  Furthermore, it is preferable that the moisture content of the wood-based raw material is constant. By making the moisture content constant, the quality variation of the molded product obtained from the wood thermoplastic resin composite is reduced. A preferable water content is 0 to 10% by weight. The method for making the water content constant is not particularly limited, but for example, a method of leaving the wood-based raw material for a certain time in a temperature-controlled oven can be mentioned. Incidentally, when left in an oven at 50 ° C. for 24 hours, the water content is maintained at about 5%.

  The wood-based raw material may be subjected to various treatments such as antiseptic and antifungal treatments. By using the wood-based raw material that has been subjected to antiseptic treatment, the molded product 9 obtained from this wood-based thermoplastic resin composite exhibits antiseptic and antifungal effects.

  In addition, after crushing the wood-based raw material as it is or to an arbitrary size, after putting it in a pressure cooker and heating it to 200 ° C., for example, releasing the pressure and crushing the material that has been ruptured by the impact of the pressure difference at that time You may add what was made into powder by the machine and was made into the crushed wood flour. As is generally known, the addition of explosive wood flour is preferable because the strength of the molded product is remarkably improved.

  The thermoplastic resin used is not particularly limited as long as the resulting molded product has excellent bending strength and can be melted by mixing and stirring. For example, fluorine resin, polystyrene resin, (meth) acrylic acid ester resin , Vinyl chloride resin, polyethylene, polypropylene (PP), polyamide, polyester resin, and the like, and only one or several of these are used in combination. These resins may contain stabilizers, lubricants and the like. Among these, polyolefin resins such as polyethylene and PP are desirable because of their low cost.

  The thermoplastic resin may be in the form of powder or pellets, but the lower the powder, the more uniform the dispersibility with the wood-based material during kneading, so the lower limit is not particularly limited. In addition, since the raw material cost is high in powder form, it is desirable to use a pellet-shaped thermoplastic resin.

An additive is not specifically limited, What is necessary is just to select suitably and use the well-known additive according to a use.
For example, additives such as α, β-unsaturated carboxylic acid monomers, mixing accelerators such as acid-modified olefins and acid-modified low-molecular olefins; reinforcing materials such as glass fibers and carbon fibers; UV absorbers and UV degradation prevention Various stabilizers such as additives and antioxidants; (internal) lubricants such as lead stearate, colorants such as pigments and extender pigments; various fillers, preservatives, flame retardants, antioxidants, nucleating agents, etc. Various additives etc. are mentioned. These additives can be used alone or in combination of two or more.

  The addition of a mixing accelerator is preferable because the adhesion between the wood-based raw material and the thermoplastic resin is improved. As the mixing accelerator, those that form a hydrophilic group in the end of the polymer or in the molecule are preferable, and the type and bonding position of the hydrophilic group are not particularly limited. Modified olefin-based admixture accelerators that form hydrophilic groups in the polymer and admixture accelerators having hydrophobicity and hydrophilicity are particularly preferred because they exhibit excellent effects even at low amounts.

  The addition amount of the various additives is not particularly limited as long as the addition amount is appropriately adjusted according to the kind of the additive so that a desired effect can be obtained. For example, when MAPP (maleic anhydride-modified polypropylene) is used as an additive, the additive is preferably added in an amount of 2 parts by mass or more with respect to a total of 100 parts by mass of the thermoplastic resin (PP) and the woody material. More preferably, it is suitably added so as to be 3 parts by mass or more, preferably 5 parts by mass or less, more preferably 4 parts by mass or less. If the additive amount is small, the additive may not sufficiently exhibit the effect of improving the adhesion between the thermoplastic resin and the woody material. Even if it is added in a large amount, a remarkable improvement effect may not be obtained.

  A method for producing a woody thermoplastic resin molding of the second aspect of the present invention is to put a predetermined weight of the above wood-based raw material and thermoplastic resin into a mixing container provided with a plurality of stirring blades, and rotate the stirring blades at high speed to obtain a piece of wood. And a thermoplastic resin, and a molten mixture obtained by mixing a thermoplastic resin melted by frictional heat generated by stirring and a wood-based material is cooled and pressed while being pressed.

  The wood-based raw material is supplied to a known melt mixing apparatus (described later) together with a thermoplastic resin, preferably an additive. Each of these raw materials may be provided with a feeder and supplied separately to the apparatus, or a premixed material may be supplied to the apparatus, and the supply method is not particularly limited.

  The melt mixer may be a general device as long as it is a device that melts the resin with frictional heat generated when mixing the wood-based raw material and the thermoplastic resin to obtain a mixture obtained by mixing the wood-based raw material. . That is, for example, as an example, the rotating shaft inserted into the melt mixing chamber is provided with a plurality of stirring blades for melting the thermoplastic resin by frictional heat, and the wood-based raw material and the resin mixed in the preceding process Is fed into the chamber and the stirring blades are rotated to obtain a molten mixture in which the wood-based raw material is mixed with the molten thermoplastic resin (for example, K-mixing machine, manufactured by Kohan (trade name) ) And the like. In this method, the wood-based raw material and the thermoplastic resin can be melt-mixed without any pretreatment such as preliminary drying, and without making the wood-based raw material into a fine powder.

  In the present invention, as the woody material, a woody material containing 20% by weight or more of crushed wood chips having a thickness or width of 1 mm or more, a length of less than 10 mm, and an aspect ratio of less than 3 is used in the piece of wood. This prevents the wood-based material from being destroyed by the high-speed rotating blades, so that the wood-based material is practically close to powder in the melt mixer chamber and is not covered with resin. Yes.

  That is, among the wood crushing chips put into the chamber, those with a thickness or width of 1 mm or more are less likely to be destroyed even under impact by high-speed agitation, and can maintain their shape. The number of times that the wood crushing chip collides with the stirring blade is reduced by setting the value to less than 3. Therefore, the woody crushing chip of this shape maintains the original shape even after melt mixing.

  The wood thermoplastic resin composite is made into a molten mixture. When the molten wood thermoplastic resin composite is filled in a press mold and cooled while being pressed, a molded product using the wood thermoplastic resin composite is used. Is obtained.

  As in the invention 3, in the molten mixture in which the wood-based raw material is mixed with the thermoplastic resin melt, the wood crushing chips in the molten mixture are distributed more on the surface than the inside, and the wood crushing chips are exposed on the surface. ing. Therefore, a molded body produced by putting it into a press mold and cooling it while being pressed has a woody material exposed on the surface of the molded body. Therefore, the appearance and feel of the molded body are close to those of wood, and a molded product using the wood thermoplastic resin composition maintaining the surface property and warmth unique to the wood-based raw material can be obtained.

  In order to obtain a molten mixture in which a large amount of wood crushing chips are distributed on the surface, the invention 4 can move the wood crushing chips between the stirring blades of the mixing vessel for producing the molten mixture and the inner surface of the vessel. Clearance and the rotation speed of the stirring blade is 3000 to 6000 rpm. Since the rotational speed is high, the thermoplastic resin put into the mixing container is melted by frictional heat, and the woody raw material is mixed with the melted resin to form a molten mixture.

  At this time, the wood crushing chips to be mixed are unevenly distributed on the inner wall side of the mixing container by the stirring blades. Since the clearance between the mixing blade and the inner wall of the mixing vessel is provided with a size that allows the movement of the wood crushing chip, the unevenly distributed wood crushing chip is unevenly distributed near the surface of the molten mixture. is there.

  In the woody thermoplastic resin composition of the invention 1, 30% by weight to 80% by weight of the raw material is 20% by weight of wood crushing chips having a thickness or width of 1 mm or more, a length of less than 10 mm and an aspect ratio of less than 3. Because it is a wood-based material that contains the above, and the remaining weight is a thermoplastic resin, it enables molding of wide building materials with less waviness and twist on the surface, while maintaining the surface properties and warmth inherent to wood-based materials The effect that the molded article using the existing wood thermoplastic resin composition is obtained is expressed.

  In invention 2, the raw material having the composition of invention 1 is put into a mixing vessel provided with a plurality of stirring blades, and the stirring blades are rotated at high speed to stir the pieces of wood and the thermoplastic resin, and friction generated by stirring. Since the thermoplastic resin melted by heat is melted, and the wood-based raw material is mixed with the melted thermoplastic resin, the wood crushing chip maintains the original shape even after the melt mixing. Furthermore, the other woody raw materials are in a fine powder state, and an effect is obtained that a molten mixture dispersed inside the molten mixture as a filler is obtained.

  Since this molten mixture is filled in a molding die of a press molding machine and cooled while being pressurized, it is possible to perform atypical molding having ribs, etc., and there is no need to attach a heating device to the press molding die. Has the effect of simplifying.

  In the invention 3, when the content of the wood crushing chips in the molten mixture is distributed more on the surface than inside the molten mixture, and the sub-crushing chips are exposed on the surface of the molten mixture, the obtained molded product is a book. It is possible to reduce the meat weight and to form a wide wood thermoplastic resin molded body without twisting or undulation, and can impart a touch and warmth peculiar to wood-based materials. Moreover, the effect that the moisture absorption / release property peculiar to a wood type raw material is provided is expressed.

  Further, in the invention 4, the clearance between the stirring blade of the mixing container for producing the molten mixture and the inner surface of the container is a clearance that allows the wood crushing chip to move, and the rotation speed of the stirring blade is 3000 to 6000 rpm. Therefore, the thermoplastic resin is melted by frictional heat, and the wood-based raw material is mixed with the melted resin to form a molten mixture, and the wood crushing chips are distributed more on the surface than inside the molten mixture.

  Embodiments of the present invention will be described below with reference to the drawings. In all the examples, PP was used as the thermoplastic resin, and crushed building waste was used as the wood-based material. The raw materials were mixed as described in Table 1 (described later), and the conditions for melting and molding the wood thermoplastic resin composite for press molding were as follows.

  FIG. 1 is a cross-sectional view showing the operating principle of a melt mixer used in the practice of the present invention. FIG. 2 is an example of a molding method of a wood thermoplastic resin composite molded article, and (a) is a schematic cross-sectional view of an example of a mass of a molten mixture containing a large amount of wood crushing chips on the surface side. ) Is a press molding step, and (c) is a cross-sectional view of the resulting molded product.

  That is, the molten mixture of the wood thermoplastic resin composite was prepared by mixing 9 kg of the raw material having the composition shown in Table 1 with the above-described general melt mixer (K-mixing machine, manufactured by Kohan (trade name), capacity 5 L, number of blades. 4 pieces, stirring speed 3600 rpm), and stirring was continued until the internal temperature reached 180 ° C. to obtain a molten mixture.

  That is, the raw material G mixed in a predetermined blending amount is put into the hopper 14 of the melt mixer 1 shown in FIG. 1, and a predetermined amount (9 kg in this example) of the mixed raw material G is rotated by an electric motor or the like. 13 to the chamber 12. A plurality of stirring blades 121 are provided in the chamber 12 for mixing raw materials and melting the thermoplastic resin by frictional heat generated at that time.

  A gap S is provided between the stirring blade 121 and the inner wall of the chamber 12 in order to smoothly rotate the stirring blade 121. When the wood-based raw material G is mixed with the molten thermoplastic resin, the wood crushing chip T having a predetermined size of G in the wood-based raw material remains substantially in its original shape even after the melt-mixing. When the wood-based raw material G is mixed into the molten resin by the stirring blade 21, a large amount of the wood crushing chips T are present on the surface side of the lump of the molten mixture 2, and the wood-based raw materials having a smaller size are , It will be dispersed inside the mass. The fine powdery wood raw materials dispersed on the inside are dispersed as a filler inside the mass of the molten mixture 2, and the mass of the molten mixture 2 is unevenly distributed with a fine size on the center side and a large size on the surface side. It becomes.

  FIG. 2 shows a method for obtaining the molded product 5 by molding the molten mixture 2. The molten mixture 2 (FIG. 2A) in the above state is taken out from the discharge port 15, and filled in the press mold 3 (length 300 mm × width 300 mm) in the molten state (FIG. 2B). The molten mixture 2 filled at a mold temperature of 20 ° C. was pressurized while being pressurized at 20 MPa to obtain a molded product 4 (FIG. 2C).

  A No. 1 dumbbell test piece was sampled from the obtained flat plate-shaped product (length 300 mm × width 300 mm × thickness 5 mm), and the elastic modulus and tensile strength were measured according to JIS K 7113. Furthermore, after leaving the flat plate for one week in an atmosphere with an air temperature of 25 ° C. and a relative humidity of 50%, it is left in a constant temperature and humidity chamber with an air temperature of 40 ° C. and a relative humidity of 90% for measuring the rate of increase in weight. did.

  Table 1 shows the blending conditions of the raw materials, the properties of the wood crushing chips, the melting conditions, and the physical properties of the obtained molded product, divided into examples (referred to as comparative examples) performed for comparison with the examples.

  The plate material of the present invention can be applied to interior materials such as building floor materials, wall materials, and ceiling materials.

It is sectional drawing which shows the principle of operation of the melt mixer used in implementation of this invention. It is an example of the shaping | molding method of a woody thermoplastic resin composite molded product, (a) is typical sectional drawing of an example of the lump of a molten mixture, (b) is a press molding process, (c) is the molded product obtained. It is sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Melt mixer 12 Chamber 121 Stirrer blade 13 Screw 14 Hopper 15 Outlet 2 Molten mixture 3 Press molding die 4 Molded product G Raw material T Wood crushing chip S Gap

Claims (4)

  30% to 80% by weight of a wood-based material containing 20% by weight or more of wood crushing chips having a thickness or width of 1 mm or more, a length of less than 10 mm and an aspect ratio of less than 3, and a thermoplastic resin of 20 to 70% by weight A woody thermoplastic resin composition comprising:   The wood thermoplastic resin composite is put into a mixing vessel provided with a plurality of stirring blades, the thermoplastic resin is melted by frictional heat by stirring, and the thermoplastic resin and the wood-based raw material are mixed to obtain a molten mixture. A method for producing a woody thermoplastic resin molded article, characterized in that the molten mixture is poured into a press mold and cooled while being pressurized.   In the molten mixture after being put into the press mold, the distribution of wood crushing chips in the molten mixture is distributed more on the surface than inside, and the wood crushing chips are exposed on the surface. The manufacturing method of the woody thermoplastic resin molding of Claim 2. The said mixing container has clearance which the said wood crushing chip | tip can move between a stirring blade and a container inner surface, and the rotation speed of a stirring blade is 3000-6000 rpm, or characterized by the above-mentioned. The manufacturing method of the woody thermoplastic resin molding of Claim 3.

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