KR102413654B1 - Eco-friendly synthetic wood containing coffee grounds and manufacturing method thereof - Google Patents

Abstract

The present invention provides an eco-friendly synthetic wood that contributes to environmental protection by using as a main component coffee foil, waste gypsum, and PETG recovered from waste plastics, which are waste resources, while reducing the shrinkage expansion rate and moisture absorption rate of the synthetic wood. Provided are an eco-friendly synthetic wood containing coffee foil capable of improving the formability, post-processing properties and weather resistance of synthetic wood, and a method for manufacturing the same.

Description

Eco-friendly synthetic wood containing coffee grounds and manufacturing method thereof

The present invention relates to an eco-friendly synthetic wood containing coffee foil and a method for manufacturing the same, and more particularly, to an eco-friendly environment that contributes to environmental protection using PETG recovered from coffee foil, waste gypsum, and waste plastics, which are waste resources, as main components. While providing synthetic wood, it is possible to reduce the shrinkage expansion rate and moisture absorption rate of synthetic wood, thereby reducing defects of synthetic wood, and including coffee foil, which can improve formability, post-processing, weather resistance, heat resistance and flame retardancy of synthetic wood It relates to an eco-friendly synthetic wood and a manufacturing method therefor.

Synthetic wood contains 50% or more of wood-based fibers and refers to flooring materials that are mainly installed outdoors. There are various types of this synthetic wood, and wood flour, rice husks, and reeds are the main components.

The wood flour has a high lignin component, and defects such as cracking, swelling, cracking, and warping may occur in synthetic wood over time. The rice hull has a characteristic of having a high specific gravity and coarse fibers, thereby reducing the life of the cylinder screw of the machine, and there is a problem in that processing is not easy due to low workability. The process of collecting and pulverizing the reeds is too complicated to process, and fine dust is generated when crushed, which can be harmful to the human body, and the powder is too light to be transported in the hopper, so it is difficult to form.

Conventional synthetic wood is manufactured by mixing such reeds and wood flour. At this time, there is a great difficulty in mixing and molding due to the difference in specific gravity between reeds and wood flour. Moreover, there is a difference in the particle shape of reeds and wood flour, so post-processing sanding (brush) There is a problem in that the synthetic wood does not look good after treatment.

In addition, one of the biggest causes of defects in such synthetic wood is the rate of shrinkage and expansion. In the case of conventional synthetic wood prepared by mixing reed and wood flour, the shrinkage and expansion rate and water absorption rate are above a certain level, so there is a problem in that defects frequently occur during the manufacture of synthetic wood.

Meanwhile, a study from the Harvard School of Public Health found that women who drank four cups of coffee, 8 ounces (about 227 milliliters) of coffee per day, had a 20 percent lower risk of developing depression. It has been found to affect the same brain chemicals.

In addition, two 8-ounce coffee cups contain about 200 mg of caffeine, and some studies have found that this amount improves long-term memory. It makes them function better, and drinking two cups of coffee a day has also been shown to help prevent liver diseases such as cirrhosis.

A Harvard University study that looked at the results of 28 studies found that drinking coffee was associated with a 33% lower risk of type 2 diabetes and a 59% lower risk of gout in men who drank coffee daily. Coffee also has the effect of lowering uric acid levels in the blood, and a 2012 study found that women who consumed three or more cups of coffee per day had a significantly lower risk of basal cell cancer.

As the efficacy of coffee is known as described above, coffee consumption is rapidly increasing every year. Accordingly, along with the increase in coffee imports, the amount of coffee grounds that are thrown away after brewing coffee is also greatly increasing every year. Coffee beans are mainly produced in coffee shops and coffee factories. According to statistics in March 2017, there are over 90,000 coffee shops in Korea, which is more than the number of chicken restaurants and convenience stores combined.

However, the Ministry of Environment's measures for recycling coffee beans are still in their infancy. Coffee beans are classified as household waste according to the Waste Management Act and most have been landfilled or incinerated.

In addition, since coffee foil has excellent moisture control ability and has a directionality, if it is used as a synthetic wood, there is an advantage in that the above characteristics can be utilized. However, even if the coffee grounds are recycled, since the synthetic wood is manufactured by adding a large amount of additional chemical additives after minimizing the content thereof, it is not environmentally friendly, and the efficiency of recycling coffee leaves is lowered.

On the other hand, a large amount of waste gypsum is generated during the desulfurization process and the manufacturing process of phosphoric acid, hydrofluoric acid, boron, and titanium. The gypsum produced in this way contains harmful impurities in itself. And it is not effective due to the limitation of the throughput as well as lowering the durability. In addition, if it is deposited in nature as it is, the risk of groundwater contamination increases.

Until now, for recycling of waste gypsum, it can be used only through a complex refining process such as washing, neutralization, calcination, and granulation. As such, it has been a cause of preventing the recycling of waste gypsum for reasons such as limited allowances for concerns about environmental hazards and more economical reasons for the producers who discharge gypsum to store them in a gypsum store than to pay for handling them. Currently, more than 3 million tons of waste gypsum is discharged in Korea per year, and about 20 million tons of gypsum is stored. This remains a problem to be solved worldwide, as in developed countries, in the case of the United States, more than 1 trillion tons are stockpiled.

Domestic Patent Publication No. 2017-0030163

The present invention has eco-friendly properties by maximally excluding chemical additives while maximally utilizing PETG recovered from waste plastics and coffee foil and waste gypsum, which are wastes, and can reduce the shrinkage expansion rate and moisture absorption rate of synthetic wood, thereby reducing product defects. An object of the present invention is to provide an eco-friendly synthetic wood containing coffee foil and a method for manufacturing the same so that the formability, post-processing, weather resistance, heat resistance and flame retardancy of the synthetic wood can be improved.

One aspect of the present invention, coffee grounds; Based on 100 parts by weight of the coffee foil, 250 to 550 parts by weight of wood-based fibers; 120 to 300 parts by weight of polyethylene terephthalate glycol (PETG); 20 to 100 parts by weight of waste gypsum; 5 to 15 parts by weight of a polyethylene (PE: Polyethylene)-based lubricant; and 5 to 15 parts by weight of an inorganic pigment; It provides an eco-friendly synthetic wood containing coffee foil containing a.

According to a preferred feature of the present invention, the coffee foil may have a water content of 15% or less, the content of ester-based oil may be 14 to 16% by weight based on the total weight of the coffee foil, and the moisture content of the waste gypsum may be 5% or less have.

Another aspect of the present invention is coffee foil and, with respect to 100 parts by weight of the coffee grounds, 250 to 550 parts by weight of wood-based fibers, 120 to 300 parts by weight of PETG, 20 to 100 parts by weight of waste gypsum, 5 to 15 parts by weight of PE lubricant. A first step of preparing a mixture by mixing 5 to 15 parts by weight of parts and inorganic pigments at 70 to 100° C. in a blender; a second step of cooling the mixture twice to lower the temperature of the mixture to 40° C. or less; a third step of putting the cooled mixture into an extruder to make pellets; and a fourth step of putting the pellets into a molding machine and molding them into synthetic wood; It provides a method for producing an eco-friendly synthetic wood containing coffee foil comprising a.

According to a preferred feature of the present invention, before the first step, the drying operation of the coffee foil may be performed by a screw heater method so that the water content of the coffee foil is 15% or less, and in the first step, the waste gypsum has a water content 5% or less can be used.

According to an embodiment of the present invention, it is possible to manufacture eco-friendly synthetic wood as well as to exclude the use of chemical additives as much as possible and to include PETG recovered from waste plastics and coffee leaves, waste gypsum, and waste plastics as main components. It can contribute to environmental protection by reducing the amount of waste and waste plastics, and it can reduce product defects by reducing the shrinkage expansion rate and moisture absorption rate of synthetic wood. There is an effect that can provide a synthetic wood having moldability, post-processing properties, weather resistance, heat resistance and flame retardancy.

1 is a flowchart illustrating a method for manufacturing synthetic wood according to an embodiment of the present invention.
Figure 2 is a photograph showing the dried coffee foil used in manufacturing the synthetic wood of the present invention.
3 is a photograph showing the collected coffee leaves.
Figure 4 is a photograph showing that the coffee foil of Figure 3 is pulverized.
5 is a photograph showing the process of collecting waste plastics.
6 is a photograph showing the process of pulverizing waste plastic.
7 is a photograph showing the pulverized waste plastic.
8 is a photograph showing the process of producing the pellets.
9 is a photograph showing the process of producing a product from the pellets.

Hereinafter, preferred embodiments of the present invention will be described. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, in the entire specification, 'including' a certain element means that other elements may be further included, rather than excluding other elements, unless otherwise stated.

The present invention is a synthetic wood obtained by recycling coffee leaves and other waste materials. As other waste materials, PETG and waste gypsum recovered from waste plastics are used. At this time, the synthetic wood of this embodiment may be a problem in the insufficient heat resistance of PETG, and since waste gypsum serves as a filler and a flame retardant, it is possible to compensate for this insufficient heat resistance and at the same time improve the flame retardancy of the synthetic wood.

The synthetic wood of the present invention may be formed in various forms such as, for example, boards or square wood, and includes coffee foil, wood-based fibers, PETG, waste gypsum, PE-based lubricants, and inorganic pigments.

At this time, the synthetic wood, coffee foil, and with respect to 100 parts by weight of the coffee foil, 250 to 550 parts by weight of wood-based fibers, polyethylene terephthalate glycol (PETG: Polyethylene Terephthalate Glycol) 120 to 300 parts by weight, waste gypsum 20 to 100 It may be configured to include 5 to 15 parts by weight of a PE lubricant and 5 to 15 parts by weight of an inorganic pigment.

As shown in Figure 2, it is preferable to use the coffee foil used in this embodiment is 15% or less moisture. At this time, the tannin contained in the coffee grounds is a natural pigment that prevents the discoloration of the pigment when exposed to ultraviolet rays, and the ester crab oil contained in the coffee foil plays the role of natural oil stain and lubricant, and the fine grain of wood flour during production. It can prevent dust generation and increase the life of production equipment.

Since the coffee foil has a property of controlling the surrounding moisture and has a directionality, when used as a synthetic wood, this property can act as an advantage that differentiates it from other synthetic wood.

In addition, since the coffee foil has a unique natural color of coffee, the synthetic wood can have a unique natural color of coffee, and at the same time, it can be expected that the color is not easily decolorized by ultraviolet rays.

At this time, the coffee foil should have a moisture content of 15% or less. When the moisture content of the coffee foil exceeds 15%, the bonding strength between the coffee foil and PETG is lowered due to moisture, so that it is difficult to obtain strength suitable for manufacturing synthetic wood.

In general, since the coffee foil from a coffee manufacturing plant has a moisture content of 60% or more, in this embodiment, it is preferable to use the coffee foil from a coffee shop having a moisture content of about 30%.

In addition, the coffee foil may contain 14 to 16% by weight of the ester-based oil based on the total weight. The ester-based oil may serve as a UV blocker, stabilizer, lubricant, antioxidant, and pigment added during the manufacture of conventional synthetic wood. In this embodiment, when manufacturing synthetic wood, chemical additives such as UV blockers, stabilizers, lubricants, antioxidants and pigments may not be added or the amount thereof may be minimized, thereby manufacturing eco-friendly synthetic wood.

When the content of the ester-based oil is less than 14% by weight, the roles of these UV blockers, stabilizers, lubricants, antioxidants and pigments are not properly implemented, and when the content of the ester-based oil exceeds 16% by weight, these UV blockers, Since the effects of the stabilizer, lubricant, antioxidant and pigment are no longer significantly increased, the maximum value of the content of the ester-based oil is preferably 16% by weight in consideration of the manufacturing cost.

The lignocellulosic fibers may be, for example, reeds, rice husks, wood flour, and the like, but the present invention is not limited thereto. These lignocellulosic fibers may serve to absorb the oil content of coffee beans.

If the content of the lignocellulosic fiber is less than 250 parts by weight based on 100 parts by weight of the coffee grounds, the content of oil contained in the coffee leaves is relatively increased, so that problems due to shrinkage and deformation of the product may occur, and the tannins contained in the coffee leaves It is difficult to see the effect on discoloration and weather resistance of wood-based fibers due to UV due to the low content of excess ester oil.

In addition, when the content of the lignocellulosic fiber exceeds 550 parts by weight based on 100 parts by weight of the coffee grounds, the content of tannins and ester-based oils contained in the coffee grounds is small, so the effect on discoloration and weather resistance of the lignocellulosic fibers by UV is shown. difficult.

The PETG may be obtained from scrap or disposable containers generated during extrusion injection molding. The PETG has excellent processability, so that products with complex shapes can be easily made, thermal adhesiveness and transparency are good, and heat resistance, chemical resistance and mechanical properties are excellent. It is also suitable for recycling, so as in this embodiment, it is a material suitable for treatment and recovery from waste plastics for use.

In this case, the particle size of the PETG may be preferably 3 to 5 mm. If the particle size of the PETG is less than 3 mm, there may be a problem of stenosis between the resins due to the heat generated during pulverization. As PETG is separated and molded, it is difficult to expect constant physical properties.

Such PETG may include 120 to 300 parts by weight based on 100 parts by weight of coffee foil. When the content of PETG is less than 120 parts by weight based on 100 parts by weight of coffee leaves, it is difficult to improve the weather resistance and strength of synthetic wood and reduce shrinkage and expansion rate, and the PETG content exceeds 300 parts by weight based on 100 parts by weight of coffee leaves In this case, since the amount of PETG added is too large, there may be a problem of increased shrinkage and expansion. In addition, as the content of coffee grounds is relatively reduced, it may be difficult to satisfy the conditions that the synthetic wood of the present invention provides excellent moisture control ability and directionality expected from coffee leaves.

On the other hand, since the PETG plays a role in determining the strength of the synthetic wood, if you want to increase the strength of the synthetic wood to be produced, you can increase the amount of PETG, and conversely, to make a synthetic wood that is closer to environment-friendly than high strength. In this case, the amount of PETG may be reduced.

In addition, the PETG can act as an oil stain that prevents moisture penetration of the atmosphere by combining with the natural oil of coffee grounds, so it is easy to manufacture and use as a product using existing wood, such as a floorboard.

Gypsum is an oxide produced in nature, and the chemical formula of gypsum is CaSO ₄ ·2H ₂ O. The color of the gypsum is colorless, white, light gray, brown, yellow, red. It can have a glass luster or pearl luster. In addition, the gypsum has a silky luster in the variety having a fibrous tissue. Transparent to translucent, colorless under flaking. In addition, the gypsum is a mineral belonging to the monoclinic system, the hardness is 2, the specific gravity is 2.32. Such gypsum is mainly used in cement manufacturing and fertilizer manufacturing.

The waste gypsum used in this example is a remnant left after making cement or fertilizer, and currently more than 20 million tons in Korea are left unattended in the sea off Yeosu, causing environmental damage. In this case, the waste gypsum used in this embodiment may preferably be dried to a moisture content of 5% or less. In this way, waste gypsum with a moisture content of 5% or less has a similar composition to heavy carbon (calcium carbonate) and can replace the role of calcium carbonate.

The PE-based lubricant may serve to facilitate the flow of waste plastics, coffee leaves, and wood-based fibers without being carbonized by the temperature in the cylinder screw. In this embodiment, 102N, an LDPE wax-based product of Lion Chemtech, may be preferably used as a PE wax-based lubricant.

If the content of the PE lubricant is less than 5 parts by weight based on 100 parts by weight of the coffee foil, the flow of the raw material is not smooth in the cylinder screw part of the extruder, and thus a problem of becoming an unmolded product may occur, and the content of the PE lubricant If it exceeds 15 parts by weight with respect to 100 parts by weight of the coffee powder, the bonding force between the raw materials is lowered and the product strength is weak, which may cause a problem in product function.

As the inorganic pigment, sulfur oxide, iron oxide, and TIO ₂ may be used, and the present invention is not limited thereto, such as further adding other components if necessary.

If the content of the inorganic pigment is less than 5 parts by weight based on 100 parts by weight of coffee foil, a problem of discoloration by ultraviolet rays may occur, and if the content of the inorganic pigment exceeds 15 parts by weight based on 100 parts by weight of coffee foil, according to the lapse of time It may elute to the outside and cause contamination upon contact.

In addition, if necessary, for reasons such as changing the color of wood, an organic pigment may be further used. In this case, the organic pigment may be, for example, carbon black.

Hereinafter, a method of manufacturing an eco-friendly synthetic wood containing coffee foil of the present invention will be described in detail with reference to an embodiment.

Referring to FIG. 1 , a first step ( S20 ) of preparing a mixture by first mixing various materials is performed.

As a material used at this time, coffee foil and, with respect to 100 parts by weight of the coffee foil, 250 to 550 parts by weight of wood fiber, 120 to 300 parts by weight of PETG, 20 to 100 parts by weight of waste gypsum, 5 to 15 parts by weight of PE lubricant parts and 5 to 15 parts by weight of inorganic pigments.

At this time, as shown in FIG. 3 , the first collected coffee leaves have a high water content and thus have a light brown color. Since coffee foils having such a high water content cannot be used as raw materials for synthetic wood, the collected coffee leaves are ground as in FIG. 4 . After drying, using a large dryer, etc., the drying operation is performed so that the moisture content is lowered to 15% or less (S10).

At this time, since the drying efficiency of the hot air drying method is very low due to the high moisture content of the initially collected coffee leaves, the drying operation of the coffee leaves may be preferably performed using the screw heater method having excellent drying efficiency.

The screw heater type drying apparatus used in this embodiment includes a semicircular electric furnace with an open top, a screw installed in the electric furnace in the longitudinal direction, and a heater installed at the bottom of the electric furnace, so that the coffee grounds are transported by the screw However, the coffee leaf may be dried in such a way that moisture contained in the coffee leaf is evaporated due to the heating of the heater installed below the screw.

As shown in FIG. 2 , the coffee foil dried in this way has a dark dark brown color, and in this case, the ester-based oil may be included in an amount of 14 to 16% by weight based on the total weight of the coffee foil.

The ester-based oil replaces the role of a UV blocker, a stabilizer, a lubricant, an antioxidant, and a pigment, etc. added during the manufacture of conventional synthetic wood, and in this embodiment, a UV blocker, a stabilizer, a lubricant, an antioxidant and Chemical additives such as pigments may not be added or the amount thereof may be minimized, thereby making it possible to manufacture eco-friendly synthetic wood.

The PETG may be obtained from scrap or disposable containers generated during extrusion injection molding. Specifically, as in FIG. 5 , waste plastic is collected, the scrap or disposable container is separated through hardness measurement and carbonization comparison, and then PETG separated through this operation is crushed through a plastic crusher as in FIG. 6 . Thus, as shown in FIG. 7, after making particles having a size of 3 to 5 mm, these particles are used as a material of the mixture.

Since the PETG plays a role in determining the strength among the properties of the mixture, if you want to increase the strength of the synthetic wood to be made, you can increase the amount of PETG. Reduce the amount of PETG.

The PETG has a disadvantage in that heat resistance is weak. The waste gypsum used in this example can be used by pulverizing the remaining residues having a moisture content of 5% or less among the remaining residues used in cement manufacturing or fertilizer manufacturing, supplementing the heat resistance of PETG, and acting as an auxiliary flame retardant to produce synthetic wood. It may play a role in improving the flame retardancy.

If the content of the waste gypsum is less than 20 parts by weight based on 100 parts by weight of coffee foil, there may be a problem that the heat resistance and flame retardancy of the synthetic wood do not satisfy the standard values, and the content of the waste gypsum is 100 parts by weight based on 100 parts by weight of coffee foil Exceeding the value may increase the load when molding synthetic wood, shorten the life of the screw of the molding device, and cause a problem in that the hole of the die is clogged.

The PE lubricant serves to facilitate the flow of PETG during extrusion without carbonization of waste plastics, coffee leaves, and wood-based fibers by the temperature in the cylinder screw. In this embodiment, preferably, 102N may be used as a PE wax-based lubricant.

The inorganic pigment is preferably sulfur oxide iron oxide TIO ₂ may be used. In addition, an organic pigment may be further used if necessary for the purpose of further changing the color of wood, and in this case, carbon black may be used as the organic pigment.

Next, it is possible to prepare a mixture by mixing the various materials prepared as above in a blender at 70 to 100 ℃ (S20).

At this time, if the temperature of the blender is less than 70 ℃, the molecular mixing between the materials is not made properly, in particular, there may be a problem that the bonding strength between the coffee foil and PETG is lowered, and if the temperature of the blender exceeds 100 ℃, at least one of the materials There may be a problem that some parts are carbonized. At this time, the preferred operating temperature of the Singhi blender may be 80°C.

Next, the second step of lowering the temperature of the mixture to 40° C. or less is performed by putting the mixture in a cooling device and cooling it twice. In this process, the lignocellulosic fibers absorb the moisture and oil remaining in the coffee grounds, thereby solving problems caused by entanglement between the raw materials caused by the ester-based oil.

Next, as shown in FIG. 8, the third step of making pellets by introducing the mixture cooled to 40° C. or less into the extruder proceeds.

The extruder may use a conical type extruder having a cylinder screw diameter of 92 mm or more. In this case, the cylinder screw is composed of five sets of heaters to enable temperature control, and a hole for discharging oil vapor may be formed in the center of the cylinder. And, the temperature of the cylinder may be, based on the direction from the hopper to the die, at No. 1 230°C, No. 2 240° C., No. 3 210° C., No. 4 210° C., and No. 5 205° C., At this time, the temperature error for each number may be ±5 ℃.

The pellets thus prepared may preferably have a diameter of 3 to 5 mm and a length of 2 to 4 mm.

Next, as in FIG. 9 , the fourth step of molding the pellets into a synthetic wood form of a desired shape is performed by putting the pellets into a molding machine. In this case, the molding machine may be used again with the previously used conical type extruder.

At this time, in order to mold the product into a desired shape, the structure of the mold may be appropriately designed. The mold is a part where the plate heater fastening part is fastened with the cylinder part of the machine, it is fastened within 300 mm, and the part from the discharge part to 300 mm serves as a cooling part through the thermal medium oil, and the temperature is maintained at 110 to 150 ° C. Should be.

In addition, the molded synthetic wood may be cooled while passing through the portion after the ejection portion in such a mold.

In addition, the synthetic wood molded in this way can be further processed to form a pattern desired by the user using an embossing machine or the like on the surface of the synthetic wood, or to smooth the surface or process the surface into a predetermined pattern form, if necessary.

The eco-friendly synthetic wood of the present invention produced by the above method, as a substitute for wood construction materials that has the advantages of wood and plastic at the same time, can be easily manufactured through extrusion molding as well as coffee as a waste By recycling foil and waste gypsum, it is possible to reduce waste, and by using waste plastic that is difficult to recycle, an eco-friendly effect can be expected to reduce the amount of plastic used.

The present invention is not limited by the above-described embodiment. Therefore, various types of substitution, modification and change will be possible by those skilled in the art within the scope not departing from the technical spirit of the present invention described in the claims, and it is also said that it falls within the scope of the present invention. something to do.

S10: coffee leaf drying step
S20: mixture preparation step
S30: mixture cooling step
S40: mixture pelletizing step
S50: Composite Wood Forming Stage

Claims (4)

coffee gourd;
With respect to 100 parts by weight of the coffee foil,
250 to 550 parts by weight of wood-based fibers;
120 to 300 parts by weight of polyethylene terephthalate glycol (PETG);
20 to 100 parts by weight of waste gypsum;
5 to 15 parts by weight of a polyethylene (PE: Polyethylene)-based lubricant; and
5 to 15 parts by weight of an inorganic pigment; Eco-friendly synthetic wood with coffee foil containing The method according to claim 1, wherein the coffee foil has a moisture content of 15% or less and an ester-based oil content of 14 to 16% by weight based on the total weight of the coffee foil,
Eco-friendly synthetic wood containing coffee foil, characterized in that the moisture content of the waste gypsum is 5% or less. Coffee foil and, with respect to 100 parts by weight of the coffee foil, 250 to 550 parts by weight of wood-based fibers, 120 to 300 parts by weight of PETG, 20 to 100 parts by weight of waste gypsum, 5 to 15 parts by weight of PE lubricant, and 5 to 15 parts by weight of inorganic pigments A first step of preparing a mixture by mixing parts by weight in a blender at 70 to 100° C.;
a second step of cooling the mixture twice to lower the temperature of the mixture to 40° C. or less;
a third step of putting the cooled mixture into an extruder to make pellets; and
a fourth step of putting the pellets into a molding machine and molding them into synthetic wood; A method for producing an eco-friendly synthetic wood containing coffee foil comprising a. The method according to claim 3, wherein, before the first step, drying of the coffee leaves is performed by a screw heater method so that the moisture content of the coffee leaves is 15% or less,
In the first step, the waste gypsum is a method for producing an eco-friendly synthetic wood containing coffee foil, characterized in that using a moisture content of 5% or less.

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