JP2001260108A - Composite board of wood and plastic, and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite board of wood and plastic, and its manufacturing method, wherein a wood tip having a size of a 100 mesh sieve can be also used, and plastic (thermoplastic resin) such as polyethylene, polystyrene, polypropylene and polyvinyl chloride which are discharged as municipal waste and inductrial waste and almost all of which are disposed of by incineration, can be utilized as a binder. SOLUTION: A wood and plastic composite board containing 40-150 pts.wt. of the thermoplastic resin to 100 pts.wt. of wood material chip and/or powder is provided. Further a method for manufacturing the wood and plastic composite board is provided wherein 100 pts.wt. of wood material chip and/or powder, and thermoplastic resin in which 40-150 pts.wt. of the thermoplastic resin is ground, are dry mixed, and after forming a mat, the mat is molded by thermo- compression.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can be obtained using plastic (thermoplastic resin) such as polyethylene, polystyrene, polypropylene and polyvinyl chloride discharged as wood waste, general waste and industrial waste such as house demolition materials. The present invention relates to a wood / plastic composite board and a method for manufacturing the same.

[0002]

2. Description of the Related Art In order to reuse waste wood such as house demolition materials, waste wood, waste paper and plastic are mixed, ground and fiberized, and the plastic is melted in the grinding process to form uniform fibers. A method for producing a wood material by heating and extruding the material into a wood material is disclosed in
90409 discloses this.

According to the prior art, there is an advantage that waste wood can be effectively used as a resource, used paper can be used as a fiber material, and waste plastic can be effectively reused.

[0004]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 8-290 is disclosed.
As is apparent from Examples 3 to 6 described on page 8 of the publication, the method for producing woody material disclosed in Japanese Patent Publication No. 409 is a method of producing fibrous wood / waste paper and plastic in a molten state. Extrusion molding of the mixture is used as building materials such as sills, wood materials used for furniture, Buddhist altars and the like.

However, it is difficult to extrude a wood chip and / or a composite material in which powder and plastic are mixed to obtain a building material or the like. In addition, there is a problem that productivity is low.

According to the present invention, wood chips having a size of 3 mm mesh sieve or larger can be used, and polyethylene, polystyrene, and the like, which are discharged as general waste and industrial waste and most of which are incinerated or landfilled, can be used. It is an object of the present invention to provide a wood / plastic composite board capable of using a plastic (thermoplastic resin) such as polypropylene or polyvinyl chloride as a binder, and a method for manufacturing the same.

[0007]

According to a first aspect of the present invention, a woody material chip and / or powder: 100 parts by weight, thermoplastic resin: 40 to 150 parts by weight. A wood / plastic composite board comprising:

[0010] The invention according to claim 2 is characterized in that wood material chips and / or powder: 100 parts by weight and 40 parts by weight to 1 part by weight.
Dry mixing 50 parts by weight of the ground thermoplastic resin,
Subsequently, after forming the mat, the mat is hot-pressed, and the method is a method for producing a wood / plastic composite board.

According to a third aspect of the present invention, there is provided a wood powder:
00 parts by weight and 40 to 150 parts by weight of the pulverized thermoplastic resin are dry-mixed, then formed by forming a mat, and then hot-pressed to form a wood-plastic composite. A method for producing a wood / plastic composite board, which comprises reheating the board to a temperature close to the melting point of the thermoplastic resin and subjecting the board to processing for imparting design properties.

According to a fourth aspect of the present invention, there is provided a pulverized wood / plastic composite board comprising 40 to 150 parts by weight of a thermoplastic resin to 100 parts by weight of wood chips and / or powder. And wood chips and / or
Or thermoplastic resin: 40 with respect to powder: 100 parts by weight
The ratio of the mixture of parts by weight to 150 parts by weight is 75/25 to 2
This is a recycled wood / plastic composite board obtained by hot pressing a 5/75 raw material.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on preferred embodiments.

[0012] The inventors discharge and incinerate waste wood such as house demolition materials and general waste and industrial waste such as, for example, waste of agricultural polyethylene waste and waste of polystyrene paper as a material for food trays. To manufacture wood-plastic composite boards that can use plastics (thermoplastic resins) such as polyethylene, polystyrene, polypropylene, and polyvinyl chloride that have been landfilled as starting materials (primary materials), include polyethylene, polystyrene, polypropylene, In order to take advantage of the characteristics of plastic (thermoplastic resin) such as polyvinyl chloride, we applied particle board manufacturing technology,
Based on hot-cold press forming, wood and plastic (thermoplastic resin) binder
The manufacturing process of plastic composite board was studied.

The present inventors have assumed a structural board, a thin plywood, a fiberboard substitute and a composite board having a design property as a wood / plastic composite board. The structural board is specified in JIS A 5908. The goal was a wood-plastic composite board that cleared the physical properties of 18 types of particle board. In addition, the resulting wood
The possibility of recycle of plastic composite board as raw material (secondary raw material) was also examined.

Therefore, the present inventors mechanically dry mix wood powder such as wood chips and / or sander powder and crushed waste plastic (thermoplastic resin), and form the mat to form a mat. Based on the process of hot-pressing this mat to obtain a wood-plastic composite board, the dimensions and shape of the chip, the mixing ratio of wood chip / waste plastic, the adhesion of plastic to the wood chip, and the layer composition of the mixture (single layer Or upper and lower surface layer and core layer 3
Layer), hot-pressing conditions, means for reducing the weight of the board, thickness, additives, and the like. As a result, by the following process, in the case of a composite board for structural surface materials, a wood / plastic composite board that clears the physical properties of 18 types of particle boards specified in JIS A 5908 could be manufactured. .

The process for obtaining a wood / plastic composite board according to the present invention comprises the steps of crushing and drying demolition wood and scraps of houses and the like to obtain wood chips, polystyrene paper which is used for agricultural waste plastics and food trays. Process of coarsely pulverizing plastic such as waste and pulverizing it to obtain pulverized plastic, weighing each of the wood chips and pulverized plastic and then dry-mixing with, for example, a cylindrical rotary stirring mixer, and forming the mixture And a step of hot-pressing the mat by hot pressing and a simple cold pressing.

First, the size of the wood chip, which is one of the starting materials, will be described. The structural board is a composite board having a thickness of 9 mm or more. A wood chip for obtaining a wood / plastic composite board as a structural surface material has a size of 20 mm mesh pass to 5 mm mesh pass and a size on a 3 mm mesh sieve.
In the case of a fine wood chip such as a 3 mm mesh pass, it cannot contribute to the strength development of the obtained composite board. On the other hand, when coarse wood chips such as those on a 20 mm mesh sieve are used, the affinity with the thermoplastic resin as the binder is deteriorated, and the strength of the obtained composite board is reduced.

Next, the thin plywood and the wood / plastic composite board as a substitute for the fiberboard are, for example, MDF (medium density fiberboard) substitutes having a thickness of about 3 mm. In this case, the wood chip used has a size of about 7 mm mesh pass and about 3 mm mesh sieve. This size range is limited by the dimensions, especially the thickness, of the composite board.

Wood chips used in the manufacture of a wood / plastic composite board, which is used as a ceiling panel, a waist wall, a door panel, or the like and has a design having a design by embossing on its surface, have a fine uneven pattern. It must be fine that can be formed. Therefore,
A powdery wood material chip finer than a 2 mm mesh pass, such as sander powder, is used.

[0019]

According to the present invention, as shown in the following embodiments,
For wood-plastic composites for structural facings,
A wood / plastic composite board having physical properties equivalent to or greater than those of 18 types of particle boards specified in JIS A 5908 could be manufactured. In the manufacturing process, it is important to remove steam during the hot pressing process. The wood / plastic composite material as a substitute for thin plywood and fiberboard obtained by the present invention is MDF (medium density fiberboard) JIS M-2.
It has physical properties equivalent to 5 types or more. Further, it is possible to obtain a composite board provided with an embossed pattern having excellent design properties and used as a ceiling panel or the like. The design and decoration of such composite boards are important, and the strength and physical properties are secondary. Therefore, they are crushed and pulverized to produce a new design and decorative wood / plastic composite board. Can be recycled.

[0020]

EXAMPLES Example 1 Layer Configuration: Single Layer Wood Chip Size: 12 mm Mesh Pass Plastic: Pulverized Waste Agricultural Polyethylene Wood Chip / Plastic Mixing Ratio: 70/30 (Weight Ratio) Board Thickness: 9 mm Additive: Melamine resin powder (addition amount (parts by weight of wood chips): 5 parts by weight) Hot pressure condition: Hot press pressure: 50 kgf / cm ² , temperature: 170 ° C, time: 10 minutes Cooling condition: Cold press pressure: 1 kgf / cm ² , time: 10 minutes

Table 1 shows the primary physical properties of the wood / plastic composite board obtained in Example 1.

[Table 1] As is clear from Table 1, except for the normal bending Young's modulus which is a reference value of JIS A 5908 relating to particle boards, a wood / plastic composite having physical properties equivalent to or greater than those of 18 types of particle boards specified in JIS A 5908. The board is obtained.

Table 2 shows the results of in-plane shear tests on the wall panels using the wood / plastic composite boards obtained in Example 1.

[Table 2] As is clear from Table 2, the wall panel for the recycle construction method made using the wood / plastic composite board cleared the target wall magnification: 5 times. Thereby, it turned out that it can be used for structural members.

Table 3 shows the sound insulation performance and moisture permeability test results of the wood / plastic composite board obtained in Example 1.

[Table 3] As is evident from Table 3, the wood / plastic composite board of the present invention has excellent sound insulation and low moisture permeability as compared with particle board and plywood.

Table 4 shows the results of the termite resistance test of the wood / plastic composite board obtained in Example 1. In addition,
The termite resistance test was conducted by JWPAS Standard No. 11, laboratory test.
According to three comprehensive tests.

[Table 4] As is clear from Table 4, the wood / plastic composite board of the present invention is superior to plywood also in termite control.

Example 2 Layer Configuration: Single Layer Wood Chip Size: 7 mm Mesh Pass Plastic: Waste Polystyrene Pulverized Wood Chip / Plastic Mixing Ratio: 60/40 (Weight Ratio) Board Thickness: 9 mm Additives: None Heat Pressure Conditions: hot press pressure: 50 kgf / cm ² , temperature: 170 ° C., time: 10 minutes Cooling conditions: cold press pressure: 1 kgf / cm ² , time: 10 minutes

Table 5 shows the primary physical properties of the wood / plastic composite board obtained in Example 2.

[Table 5] Since polystyrene has lower flexibility than polyethylene, it has a normal normal bending Young's modulus of 3000 N / mm ² or more without adding a powdered melamine resin and has a JISA 5
The standard of the particle board 18 type specified in 908 was able to be cleared. Further, as is apparent from Table 5, other primary physical properties were improved by about 10% as compared with the wood / plastic composite board obtained in Example 1.

Example 3 As a substitute for thin plywood and fiberboard, set thickness: 2.7 mm
Manufactured a wood-plastic composite board. In the case of a thin material, the efficiency of removing steam during hot pressing is good,
The higher the content of waste polystyrene as a thermoplastic resin, the better the finish without breakage during hot pressing.

In this embodiment, the mixing ratio of wood chip / crushed plastic is 50/50 (weight ratio),
A wood / plastic composite board was manufactured under the conditions of a set thickness: 2.7 mm and a set specific gravity: 0.8. The resulting wood
Physical properties of plastic composite board, thickness: 2.7mm,
It is shown in Table 6 in comparison with JIS M-25 type MDF (medium density fiberboard).

[0029]

[Table 6] As is clear from Table 6, the thin wood / plastic composite board has a sufficient strength as compared with MDF (medium density fiberboard), and has physical properties such as moisture permeability and termite resistance that are higher than those of MDF. Are better.

Example 4 A composite board was manufactured under the following conditions in order to obtain a wood / plastic composite board excellent in design. Layer composition: Single layer Wood chip size: Sander powder (fine powder with a particle size of 2 mm mesh pass or less) Plastic: Waste polystyrene pulverized Wood chip / plastic mixture ratio: 50/50 (weight ratio) Board thickness: 5 mm Additive : None Hot pressure condition: Hot press Pressure: 50 kgf / cm ² , Temperature: 170 ° C., Time: 2 minutes Cooling condition: Cold press Pressure: 1 kgf / cm ² , Time: 10 minutes

The wood / plastic composite board thus obtained is kept for 10 to 15 minutes in a furnace maintained at an ambient temperature of 170 ° C., which is a temperature close to the melting point of polystyrene, and then at a pressure of 23 kgf / cm ² . It was pressed for 1 minute to give an embossed pattern. Specific gravity: 1.0 g / cm ³ ,
A composite board having a pattern with excellent design properties that can be used as a ceiling material or the like was obtained. In the composite board as in the present embodiment, designability, decorativeness is important,
Strength properties are secondary.

Example 5 The inventors carried out a recycle process in which a composite board was obtained again using the wood / plastic composite board for structural surface material obtained by the production method of the present invention as a raw material (secondary raw material). did. Table 7 shows the mixing ratio of the raw materials (primary raw materials) of the wood / plastic composite board obtained by the production method of the present invention and the physical properties of the obtained composite board. The hot pressing conditions were as follows: temperature: 170 ° C., time: 20 minutes.

[Table 7]

The composite board was pulverized by a swing hammer type pulverizer to obtain a secondary raw material. Without classifying secondary raw materials,
Used as is. A composite board was manufactured by changing the mixing ratio of the pulverized secondary raw material and the primary raw material, and a physical bending test was performed to confirm physical properties. The primary raw material is a mixture of wood chips / crushed polystyrene = 60/40 in advance. Table 8 shows the test results.

[0034]

[Table 8] As is clear from Table 8, secondary material / primary material = 75 /
When the mixing ratio is set to 25, 50/50, or 25/75, the target strength as a structural surface material, JISA 5
908 is defined, particle board 18 type (bending strength in a normal state: 18 kgf / mm ² or more, normally flexural Young's modulus: 3000 kgf / mm ² or more) could be cleared. In particular, secondary material / primary material = 50/5
When the mixing ratio was 0, 25/75, the same strength physical properties as those of the composite board manufactured using only the primary raw material could be obtained. Thus, when waste polystyrene is used, the secondary material: 50% can be recycled.

When using agricultural polyethylene as a raw material,
It is preferable that the mixing ratio of secondary raw material / primary raw material is 25/75.

Example 6 The inventors manufactured a composite board by a recycle process of obtaining a wood / plastic composite board using only secondary materials. As a result, when 100% of the secondary material was used, the strength level of the wood / plastic composite board obtained from only the primary material could not be maintained. Therefore, an attempt was made to produce a wood / plastic composite board by adding ground polystyrene, which is one of the primary materials, to the secondary material. Table 9 shows the amount of the discarded polystyrene waste and the strength properties of the obtained composite board.

[0037]

[Table 9] As is clear from Table 9, a composite produced from only the primary material was added by adding 20 to 40 parts by weight of a pulverized waste polystyrene, which is one of the primary materials, to 100 parts by weight of the secondary material. A composite board having strength properties comparable to the board can be obtained.

[0038]

According to the present invention, plastics (thermoplastic resins) such as polyethylene and polystyrene, which are discharged as waste wood and general waste or industrial waste such as house demolition materials and mostly incinerated, are utilized. hand,
A wood / plastic composite board with excellent physical properties can be obtained as a building material such as a structural face material, a thin plywood, or a fiberboard substitute, and it can be used as a decorative material such as a waist wall, a ceiling panel, and a door panel. A wood / plastic composite board with excellent design properties can be obtained.

According to the third aspect of the present invention, the wood / plastic composite board is reheated to near the melting point of the plastic by utilizing the properties of the thermoplastic resin, whereby embossing and the like can be performed. Excellent wood / plastic composite boards can be provided. The wood / plastic composite board having excellent design properties can be 100% recycled into a new design / decorative wood / plastic composite board by crushing and pulverizing the board.

According to the fourth aspect of the present invention, a recycled wood / plastic composite board for obtaining a wood / plastic composite board again using a wood / plastic composite board as a structural surface material as a raw material (secondary raw material). Can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) // B29K 105: 06 B29K 105: 06 311: 14 311: 14 B29L 31:10 B29L 31:10 F term ( Reference) 2B260 AA11 AA20 BA01 BA05 BA15 BA18 CB01 CD02 CD04 DA01 DA18 EA01 EA04 EA05 EB02 EB04 EB06 EB15 EB21 4F204 AA50 AH47 AH48 FA01 FB01 FB21 FF21 FF51 FN07 FN11 FN15 FQ01 AF011001

Claims (4)

[Claims] 1. Wood chips and / or powder: 10
A wood / plastic composite board comprising 40 parts by weight to 150 parts by weight of a thermoplastic resin with respect to 0 parts by weight. 2. Wood chips and / or powder: 10
0 weight part and 40 weight parts to 150 weight parts of the pulverized thermoplastic resin are dry-mixed, then formed by forming a mat, and then hot-pressed. A method of manufacturing a composite board. 3. Wood material powder: 100 parts by weight and 40 to 150 parts by weight of the pulverized thermoplastic resin are dry-mixed, then formed into a mat, and then hot-pressed. A method for producing a wood / plastic composite board, which comprises reheating the resulting wood / plastic composite board to a temperature close to the melting point of the thermoplastic resin to give a design property. 4. Wood chips and / or powder: 10
Pulverized wood / plastic composite board having 40 parts by weight to 150 parts by weight with respect to 0 parts by weight of thermoplastic resin, and 100 parts by weight of wood chip and / or powder: with respect to 100 parts by weight of thermoplastic resin: A recycle wood / plastic composite board obtained by hot-pressing a raw material having a mixture ratio of 40 parts by weight to 150 parts by weight of 75/25 to 25/75.