JP4087171B2 - Manufacturing method of resin molding containing wood flour - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a wood powder-containing resin molded body that can be suitably used particularly for an interior material for an architecture, an exterior material, a base material, and the like.
[0002]
[Prior art]
Products made by mixing resin and wood powder and molded by extrusion, injection, etc., can have a wooden texture in appearance and feel compared to those obtained by molding the resin alone, and also due to fading, corrosion, and termites Eating damage is much better than wood, and it has the advantages of wood and resin.
[0003]
In addition, regarding the preservation of the global environment, which shows an increase in wealth, carbon is fixed because it can be reused by crushing, crushing it into wood powder, mixing it with resin, and molding it without incineration of wooden construction waste, etc. Can be connected. Because of these advantages, the product has attracted attention in recent years, and various inventions have been made for the product and its manufacturing method.
[0004]
Among them, when the weight occupied by wood flour in the entire product is 50% or more, it can be processed as wood, and therefore various attempts have been made to increase the amount of wood flour blended with the resin.
[0005]
For example, a product obtained by blending wood powder with a vinyl chloride resin to prepare a molding resin composition, and molding the composition by injection molding or extrusion molding, and a method thereof have been proposed.
[0006]
In addition, when a resin having a small MI is used, the wood powder is difficult to be uniformly dispersed in the molding resin composition. Therefore, the molding resin composition is prepared by blending the wood powder into an olefin resin having a relatively large MI. Methods have been proposed for making and extruding or injection molding the composition.
[0007]
[Problems to be solved by the invention]
However, among the products as described above and the production method thereof, using vinyl chloride resin, the dispersibility of the wood flour in the molding resin composition is good, and the moldability is excellent. There is a possibility that harmful substances may be generated in the treatment when it is no longer needed, and there is a concern about generation of harmful hydrogen chloride gas especially when incinerated.
[0008]
In addition, it is sufficient to mix a wood powder with an olefin-based resin having a relatively large MI to create a molding resin composition by directly feeding it into an extruder or injection molding machine and stirring with a screw while melting. If the wood powder is to be dispersed, it is necessary to extremely increase the L / D value of the extruder for extrusion molding, and the equipment becomes large and expensive. In order to sufficiently disperse the wood flour in the composition with an ordinary L / D extruder, it is necessary to create a molding resin composition in the form of pellets or granulation raw materials once with an extruder or special mixer There is. Such a molding resin composition is again injected into an extruder or injection molding machine to perform molding, but it takes an extra step of forming the composition, and extra heat is required to repeat melting and cooling. It was also necessary.
[0009]
If an olefin resin having a relatively large MI is used, extrusion pressure cannot be applied to the molten molding resin composition, and extrusion molding itself becomes difficult. In order to perform extrusion molding using an olefin-based resin having a relatively large MI, the extrusion pressure is applied to the molten molding resin composition by molding while cooling without releasing the pressure in the extruder. Although it is possible to mold, in such a method, the speed of extrusion is limited, and there is a problem in efficiency in production.
[0010]
Therefore, the present invention is intended to solve the above-described problems and to provide a method for producing a wood powder-containing resin molded body in which wood powder is blended at a high ratio and the production efficiency is high.
[0011]
[Means for Solving the Problems]
As a result of earnest research, the inventors have blended wood powder with a bulk specific gravity of 0.2 or more into a polyolefin-based synthetic resin and molded it, so that the wood powder can be blended at a high ratio and the efficiency in production can be increased. As a result, the present invention has been completed.
[0012]
That is, the method for producing a wood powder-containing resin molded article according to the present invention comprises 50 to 90% by weight of wood powder having a bulk specific gravity of 0.2 or more and 10 to 50% by weight of olefin synthetic resin. A method of molding a compounded resin molding, wherein the resin extruded from an extruder is shaped by a sizing mold.
[0013]
By using the polyolefin-based resin, it is possible to suppress the generation of harmful substances such as harmful hydrogen chloride gas during incineration. Moreover, the wood powder having a bulk specific gravity of 0.2 or more is compared with a wood powder having a bulk specific gravity of about 0.1 to 0.15, which is a wood powder (hereinafter referred to as a conventional wood powder) used for forming a conventional woody molded product. Since it has few voids and is easily dispersed in the resin, it can be blended at a high ratio, and even if it is directly fed into the molding machine without creating pellets or granulation raw materials, It can be easily kneaded with a resin, and the production efficiency can be high. Moreover, since the wood powder has a large bulk specific gravity, it is possible to increase the weight of the wood powder with respect to a certain volume, and it is easy to increase the weight ratio of the wood powder.
[0014]
Here, the wood powder used for forming the conventional woody molded product is obtained by crushing and pulverizing wood and the like, and the gap between the wood powder particles becomes smaller as the particle size of the wood powder becomes smaller. However, the bulk specific gravity of the conventional wood flour is limited to about 0.1 to 0.15. Wood flour with a bulk specific gravity of 0.2 or more is obtained by physically compressing ordinary crushed and pulverized wood flour to further reduce voids, and the physical bonding force required at the time of molding is easily released. Therefore, the obtained molded product does not have a portion where the wood powder is concentrated, and the mechanical strength can be prevented from being lowered.
[0015]
Moreover, the manufacturing method of the wood powder compounding resin molding concerning this invention contains 70-90 weight% of wood flour 0.4-0.6 bulk specific gravity, and contains 10-30 weight% of olefin synthetic resins. A method of molding a wood powder-containing resin molded body, wherein the resin extruded from an extruder is shaped by a sizing mold.
[0016]
According to the present invention, by using wood flour having a bulk specific gravity of 0.4 to 0.6, the same effect as that of the invention according to claim 1 can be obtained, and a wood having a bulk specific gravity of 0.4 to 0.6. Since the powder has few voids and a small particle size, the wood powder is densely present in the resin, and the molded body has a higher specific gravity and improved strength than those using ordinary wood powder. The bending strength and Young's modulus, which are disadvantages of the conventional wood powder-containing resin molded body, can be increased.
[0017]
Here, wood flour with a bulk density of 0.4 to 0.6 is obtained by further breaking down the conventional wood flour obtained by pulverization into fine particles by breaking down the pipes and phloem pipes using a compressor or the like. Mainly having a scaly shape. Such wood powder has a small particle size, and there are few voids derived from conduits and pedestrian tubes, and there is very little moisture in the voids like normal wood powder, making it difficult to absorb moisture. Even at the time of thermoforming such as extrusion and injection, it is possible to prevent a decrease in resin pressure and generation of nests due to vaporization of contained water. Such wood flour may be used in the form of a powder, or may be compressed and granulated to facilitate handling.
[0018]
The method for producing a wood powder-containing resin molding according to the present invention is characterized in that the olefin-based synthetic resin has an MI of 10 or more.
[0019]
Moreover, the manufacturing method of the wood powder compounding resin molding concerning this invention contains 50-90 weight% of wood flours with a bulk specific gravity of 0.2 or more, and contains 10-50 weight% of olefin synthetic resins. A resin molded body having a compounded resin molded body as an inner layer and an outer layer, wherein the outer layer contains 60 to 100% by weight of a thermoplastic resin and 0 to 40% by weight of a filler. A method of molding a body, wherein a resin extruded from an extruder is shaped by a sizing mold.
[0020]
Further, the filler is wood powder.
[0021]
Further, the outer layer is characterized in that a woody pattern is formed.
[0022]
[0023]
According to the method for producing a wood powder-containing resin molded body according to the present invention, it is possible to mold without applying extrusion pressure so much by using wood powder having a bulk specific gravity of 0.2 or more. It is not necessary to continue to apply the extrusion pressure while cooling at the time, and it is possible to reshape the sizing mold by releasing the extrusion pressure once. Therefore, it is not necessary to reshape while cooling. Efficiency can be increased.
[0024]
Moreover, the manufacturing method of the wood powder-containing resin molded body according to the present invention is characterized in that, in any of the above manufacturing methods, the extruder includes a wood powder drying step and a wood powder and resin kneading step. It is what.
[0025]
The wood powder and resin kneading step is characterized in that a screw of a conical type is used.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be specifically described below with reference to the drawings.
FIG. 1 shows an embodiment according to the present invention, and is a perspective view showing a wood powder-containing resin molded body according to the present invention. 1 shows a molded article 10 containing 20% by weight of a polyolefin-based synthetic resin having an MI of 10 or more and 80% by weight of a wood flour having a bulk specific gravity of 0.2 or more and obtained by molding with heat.
[0027]
The polyolefin-based synthetic resin is not particularly limited as long as it can be molded, and an α-olefin polymer such as ethylene, propylene, and butene may be used alone. A copolymerized product may be used.
[0028]
The MI of the polyolefin-based synthetic resin is preferably 10 or more. Wood flour having a bulk specific gravity of 0.2 or more is relatively easily dispersed, but when it is contained in an amount of 50 to 90% by weight, it is difficult to disperse in a resin having a small MI. By setting the MI to 10 or more, the wood powder can be smoothly dispersed, and the fluidity is enhanced, thereby facilitating molding.
[0029]
Furthermore, it is more preferable to use wood flour having a bulk specific gravity of 0.4 to 0.6. By using such wood powder of bulk specific gravity, it becomes easier to disperse and form the wood flour in the resin, and it is easier to contain 70 to 90% by weight of wood flour in the molded body.
[0030]
FIG. 2 shows an embodiment according to the present invention. The inner layer contains 20% by weight of a polyolefin-based synthetic resin having an MI of 20 or more and 80% by weight of wood flour having a bulk specific gravity of 0.2 or more. It is a perspective view which shows the molded object which used what contained 60-100 weight% of resin and 0-40 weight% of fillers as an outer layer.
[0031]
Since the inner layer 1 contains 80% by weight of wood flour, there is a high possibility that a portion that is not covered with the resin will appear, and if the inner layer 1 is exposed on the outer surface, a portion where the wood flour is exposed is generated and the portion is corroded. There is a risk of being damaged by termites. In order to prevent such a problem, the outer layer 2 is formed outside the inner layer 1 to form a molded body 10.
[0032]
The outer layer 2 may be adhered to the inner layer 1 with an adhesive or the like, but is molded simultaneously with the molding of the inner layer 1 using a compatible synthetic resin for the olefin-based synthetic resin used for forming the inner layer 1. It is preferable. By forming by such a method, the outer layer 2 can be formed in the same process as the case of forming the inner layer 1 alone without performing deposition or the like, and the production can be efficient.
[0033]
As described in the previous section, the outer layer 2 is preferably made of a synthetic resin that is compatible with the synthetic resin used to form the inner layer 1, and the inner layer 1 and the outer layer 2 are sufficiently integrated by being molded simultaneously. It becomes. Moreover, in order to form the outer layer 2, a synthetic resin may be used independently and a filler may be mix | blended. For the purpose of improving moldability, weather resistance, etc., a plasticizer, a stabilizer, a foaming aid, an ultraviolet absorber, a pigment, and the like may be blended as necessary.
[0034]
As the filler, as inorganic filler, silica powder, alumina powder, mica powder, glass fiber, talc, glass fiber, calcium carbonate, barium sulfate, aluminum hydroxide, calcium hydroxide, clay, milled fiber, sand, stone, Examples of organic fillers such as minerals and microballoons include cellulose powders such as wood powder and pulp, organic fibers, plastic powders, and crosslinked powders such as silicone and phenol. These may be used alone or in combination of two or more.
[0035]
As the filler used for the outer layer 2, wood flour is preferably selected from the group described in the previous section. The wood powder-containing resin molded body according to the present invention is suitably used for architectural applications as described above, and can be provided with a wood texture in appearance and touch by blending wood powder. If the filler is wood powder, it can be reused easily by crushing, crushing, etc. and using it again as a raw material even when the molded body is no longer needed.
[0036]
Moreover, the outer layer 2 may form a wood-like pattern, and by forming such a pattern, it is possible to provide a wooden texture that is stronger in appearance and touch. A wood-like pattern may be formed by processing such as embossing or sanding, and a plurality of colored synthetic resin materials colored in different tones are mixed as described in Japanese Patent Application Laid-Open No. 2000-301670 by the present applicant. May be formed.
[0037]
FIG. 3 is a perspective view showing an embodiment of a wood powder mixed resin molded body according to the present invention. An outer layer 2 is formed on the upper surface of the inner layer 1 to form a molded body 10, and can be suitably used for a flooring of a building.
[0038]
FIG. 4 is a perspective view showing an embodiment of a wood powder mixed resin molded body according to the present invention, and shows a molded product 10 in which an inner layer 1 is formed on the outer side of a pipe 3 and an outer layer 2 is formed on the outer side thereof. It is. By using the pipe 3 made of metal, the steel pipe can be provided with a strength much higher than that of the resin molded product while having a wooden texture in terms of appearance and touch.
[0039]
FIG. 5 is a perspective view showing an embodiment of the wood powder mixed resin molded body according to the present invention, in which a molded body 10 having an outer layer 2 formed on the outer side of the inner layer 1 and having a hollow portion 101 opened downward is shown. It is shown. By setting it as such a shape, the molded object 10 can be made to fit in the core material formed using the metal etc., and it can use it suitably for a handrail etc. In order to make it easy to fit the core material, it is preferable to use a flexible resin such as an elastomer as the olefin-based synthetic resin used to form the inner layer 1.
[0040]
FIG. 6 is an explanatory view showing an embodiment of a manufacturing apparatus for a wood powder blended resin molded body according to the present invention. In the present embodiment, a molded body is formed by extrusion molding. Wood powder is put into the hopper H1, stirred by the screw of the extruder E, and heated to reduce the water content. If moisture is contained in the wood powder, it will be vaporized during molding, leaving bubbles in the molded product, or explosively expelling when molding pressure is applied, which is dangerous because it is dangerous. It is preferable that the water content be 2% by weight or less.
[0041]
The dried wood powder is sent to the extruder E, mixed with the olefin-based synthetic resin charged from the hopper H2, stirred by the screw of the extruder E, kneaded, and extruded or extruded in a molten or softened state. Sent to type K. The molded body 10 whose shape is adjusted to some extent by the extrusion mold K is sent to the sizing mold S and shaped while being cooled. The molded body 10 shaped by the sizing mold S is cooled in the cooling tank R and taken up by the take-up machine T.
[0042]
FIG. 7 shows a cross section of the above embodiment, and the wood powder W supplied from the hopper H1 to the extruder E is stirred by the screw C and heated by the extruder E in the drying step P1. The moisture contained in is converted into water vapor and is dried by being discharged from the vent B1. The dried wood powder W is sent to the extrusion step P2, mixed with the olefin-based synthetic resin F supplied from the hopper H2, and stirred and kneaded by the screw C to obtain the composition M. Unnecessary gas generated from the olefin resin F and the wood powder P is discharged from the vent B2. By connecting the wood powder drying process P1 and the extrusion process P2 in this way, the dried wood powder can be sent to the wood powder and resin kneading process without discharging, preventing scattering of the wood powder. In addition, the amount of heat can be saved without the need for reheating.
[0043]
The composition M is sent to the extrusion mold K in a melted or softened state, and is discharged as a molded body 10 in a state where the shape is adjusted to some extent by the extrusion mold K. The discharged molded body 10 is further shaped while being cooled by the sizing mold S, and cooled in the cooling bath R.
[0044]
The screw C of the extruder E is preferably a conical biaxial screw. The conical biaxial screw has a high kneading ability between the resin and the filler, and can be suitably used to uniformly disperse the wood flour in the molding resin composition according to the present invention. The biaxial screws may be in different directions or in the same direction.
[0045]
【The invention's effect】
According to the invention described in claim 1, by using the polyolefin resin, it is possible to suppress the generation of harmful substances such as harmful hydrogen chloride gas at the time of incineration. Moreover, the wood powder having a bulk specific gravity of 0.2 or more is compared with a wood powder having a bulk specific gravity of about 0.1 to 0.15, which is a wood powder (hereinafter referred to as a conventional wood powder) used for forming a conventional woody molded product. Since it has few voids and is easily dispersed in the resin, it can be blended at a high ratio, and even if it is directly fed into the molding machine without creating pellets or granulation raw materials, It can be easily kneaded with a resin, and the production efficiency can be high. Moreover, since the wood powder has a large bulk specific gravity, it is possible to increase the weight of the wood powder with respect to a certain volume, and it is easy to increase the weight ratio of the wood powder.
[0046]
According to invention of Claim 2, while using the wood flour of bulk specific gravity 0.4-0.6, while obtaining the same effect as the invention of Claim 1, bulk specific gravity of 0.4- Since 0.6 wood powder has few voids and small particle size, the wood powder is densely present in the resin, and the molded body has a higher specific gravity than that using ordinary wood powder. At the same time, the strength is improved, and the bending strength and Young's modulus, which are disadvantages of the conventional wood powder-containing resin molded body, can be increased.
[0047]
Further, according to the method for producing a wood powder-containing resin molded body according to the present invention, the wood powder having a bulk specific gravity of 0.2 or more can be molded without applying much extrusion pressure. There is no need to continue to apply extrusion pressure while cooling in the machine, and the extrusion pressure can be released once and shaping with a sizing mold is possible, so there is no need for shaping while cooling and production is achieved by increasing the line speed. The efficiency in the can be increased.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment according to the present invention.
FIG. 2 is a perspective view showing an embodiment according to the present invention.
FIG. 3 is a perspective view showing an embodiment according to the present invention.
FIG. 4 is a perspective view showing an embodiment according to the present invention.
FIG. 5 is a perspective view showing an embodiment according to the present invention.
FIG. 6 is an explanatory view showing an embodiment of an apparatus for producing a wood powder blended resin molded body according to the present invention.
FIG. 7 is a cross-sectional view showing an embodiment of an apparatus for producing a wood powder-containing resin molded body according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Inner layer 2 Outer layer 3 Pipe 10 Molding body 101 Hollow part E Extruder H Hopper K Extrusion die S Sizing R Cooling tank P1 Drying process P2 Extrusion process B Vent W Wood powder F Olefin type synthetic resin M Composition

Claims (8)

  A method for molding a wood powder-containing resin molded body containing 50 to 90% by weight of wood flour having a bulk specific gravity of 0.2 or more and 10 to 50% by weight of an olefin synthetic resin, which is extruded from an extruder. A method for producing a wood powder-containing resin molded product, wherein the resin is shaped by a sizing mold.   A method for molding a wood powder-containing resin molded body containing 70 to 90% by weight of wood powder having a bulk specific gravity of 0.4 to 0.6 and 10 to 30% by weight of an olefinic synthetic resin. A method for producing a wood powder-containing resin molded product, comprising shaping a resin extruded from a machine with a sizing mold.   The method for producing a wood powder-containing resin molded article according to claim 1 or 2, wherein the olefin-based synthetic resin has a MI of 10 or more.   Resin molded body containing a wood powder-containing resin molded body containing 50 to 90% by weight of wood powder having a bulk specific gravity of 0.2 or more and 10 to 50% by weight of an olefinic synthetic resin as an inner layer, and forming an outer layer The outer layer is a method of molding a wood powder-containing resin molded body containing 60 to 100% by weight of a thermoplastic resin and 0 to 40% by weight of a filler, and is a resin extruded from an extruder. A method for producing a wood powder-containing resin molded article, characterized by shaping a sizing mold.   The method for producing a wood powder-containing resin molded body according to claim 4, wherein the filler is wood powder.   The method for producing a wood powder-containing resin molded body according to claim 4 or 5, wherein the outer layer is formed with a woody pattern.   It is a manufacturing method of the wood flour compounding resin molding according to any one of claims 1 to 6, wherein the extruder comprises a wood powder drying step and a wood powder and resin kneading step. A method for producing a wood powder-containing resin molded body.   The method for producing a wood powder-containing resin molded body according to claim 7, wherein the kneading step of the wood powder and the resin uses a conical biaxial screw.

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