JPH10309707A - Woody molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a woody effect similar to natural lumber by specifying the rate of a total cross sectional area of a woody molded article formed by coating the outer surface of lumber with a coating layer of a foamed resin composition consisting of a specific synthetic resin and wood powder. SOLUTION: The surface of lumber is coated with a coating layer made of foaming a resin composition filled with 1-100 pts.wt. wood powder in 100 pts.wt. synthetic resin, and the rate of a cross sectional area of lumber is made 40-90% with respect to the total cross section of a woody molded article. For example, 1 pts.wt. azodicarbonamide is added to a composition having 50 pts.wt. wood powder of 100 meshes or lower to 100 pts.wt. polyvinylchloride, and a coating layer is formed on the outer periphery of lumber by use of a head die having its cross section formed into a threshold. Furthermore, two stripes of a recessed groove are formed on the surface for making a woody molded article being 70% in the rate of a cross section of lumber with respect to the total cross sectional area of the woody molded article. In this manner, a woody molded article is obtained having the same strength as natural lumber and a woody effect similar to natural lumber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wooden molded product which is a composite material of wood and a synthetic resin, which is used as a decorative board such as a rim, a skirting board, a sill and furniture in a house, and an interior member of a vehicle. .

[0002]

2. Description of the Related Art In recent years, a synthetic resin molded article has been given characteristics close to the surface characteristics of natural wood, and the surrounding edge of a house-made member, a skirting board, a sill, furniture or a vehicle interior member has been made of natural wood. Attempts have been made to make the texture closer to that of the original. As means for making the texture close to that of natural wood, a woody article is obtained by coloring the wood in a color tone similar to that of wood, adding a predetermined amount of wood powder to synthetic resin, and foaming.

[0003] However, since the linear expansion coefficient of synthetic resin is larger than that of wood, expansion and contraction by temperature is large. For this reason, it is necessary to design in consideration of the expansion and contraction width, and there is a problem that a squeak sound is generated when a gap is generated by expansion and contraction.
Further, on a floor of a house such as a sill, there is a problem that rigidity of a synthetic resin molded product is lower than that of wood, so that it cannot be used with a similar design to wood in terms of strength.
In addition, there is a problem in that wood is warped due to humidity, has a non-uniform wood grain pattern due to nature, and high-quality products having a uniform wood grain are expensive and difficult to obtain.

[0004]

In order to achieve the above-mentioned object, the present invention relates to a method for producing 100 parts by weight of synthetic resin and 1 to 100 parts of wood flour.
A wooden molded article in which the outer surface of wood is covered with a coating layer obtained by foaming a resin composition consisting of parts by weight, wherein the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wooden molded article is 40 to 95%. Features.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. In the present invention, examples of the synthetic resin include a polyvinyl chloride resin and an ABS resin. The amount of wood flour to be filled was 1 to 10 wood flour per 100 parts by weight of synthetic resin.
0 parts by weight. If the amount of wood flour is less than 1 part by weight, a woody feeling cannot be obtained, and if it is added more than 100 parts by weight, resin melt viscosity increases, resulting in poor molding or uneven foaming, and the woody feeling is impaired. It is. Examples of the foaming agent include azodicarbonamide and dinitrosopentamethylteramine, which are organic foaming agents. These organic foaming agents are added in an amount of 0.5 to 5 parts by weight with respect to 100 parts by weight of the synthetic resin, so that the expansion ratio is 1.5 to 2.5 times.

[0006] Glued wood, veneers and the like are used as the core wood, and the wood cut to a predetermined size is supplied to an extruder having a crosshead die, and a synthetic resin is extruded with a screw through the crosshead die to form a core. And cool it down to form a synthetic resin coating on the outer surface of the wood. Applying a woodworking adhesive such as a vinyl acetate emulsion to the outer periphery of the wood, or forming a hot melt adhesive layer by co-extrusion can increase the adhesive strength between the synthetic resin and the wood.

[0007]

【Example】

(Example 1) 100 parts by weight of polyvinyl chloride resin
1 part by weight of azodicarbonamide was added to a composition filled with 50 parts by weight of wood flour or less, and using a head die having a sill-shaped cross section, a thickness of 33 mm, a width of 90 mm,
A covering layer having a foaming ratio of 1.5 times is formed on the outer peripheral surface of a 1800 mm long wood, and the dimensions of the wooden molded product are 45 mm thick, 98 mm wide, 21 mm wide as a sill groove, and 3 mm deep.
Was formed on the surface to obtain a wood molded product in which the ratio of the sectional area of wood to the total sectional area of the wooden molded product was 70%.

(Example 2) A crosshead die having a cross-sectional shape of a periphery obtained by adding 1 part by weight of azodicarbonamide to a composition in which 100 parts by weight of polyvinyl chloride resin is filled with 100 parts by weight of wood flour of 100 mesh or less. Is used to form a coating layer having a foaming ratio of 1.5 times on the outer peripheral surface of wood having a thickness of 15 mm, a width of 50 mm and a length of 1800 mm, and the dimensions of the wooden molded product are 17 mm in thickness and 55 mm in width. A wooden molded product was obtained in which the ratio of the sectional area of the wood to the sectional area was 80%.

(Example 3) A crosshead die having a threshold cross section was prepared by adding 1 part by weight of azodicarbonamide to a composition in which 100 parts by weight of polyvinyl chloride resin and 50 parts by weight of wood flour having a size of 100 mesh or less were added. 33 mm thick and 90 mm wide with a vinyl acetate emulsion applied to the surface using
mm, the expansion ratio is 1.
5 times coating layer is formed, the size of the wooden molded product is 45m thick
m, 98 mm in width, 21 mm in width as a sill groove, 3 mm in depth, and 3 mm in depth, formed on the surface two grooves, and the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wood-formed product was 70%. Product was obtained.

(Example 4) A crosshead die having a sill-shaped cross section was prepared by adding 1 part by weight of azodicarbonamide to a composition in which 100 parts by weight of polyvinyl chloride resin was filled with 50 parts by weight of wood flour of 100 mesh or less. 37 mm thick and 80 cm wide with a vinyl acetate emulsion applied to the surface using
mm, the expansion ratio is 1.
5 times coating layer is formed, the size of the wooden molded product is 45m thick
m, 98 mm in width, 21 mm in width as a sill groove, 3 mm in depth, and 3 mm in depth, formed on the surface two grooves, and the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wood-formed product was 70%. Product was obtained.

(Example 5) A crosshead die having a sill-shaped cross section was prepared by adding 1 part by weight of azodicarbonamide to a composition in which 100 parts by weight of a polyvinyl chloride resin was filled with 50 parts by weight of wood flour of 100 mesh or less. A vinyl acetate emulsion was coated on the surface with a thickness of 28 mm and a width of 70 mm.
mm, the expansion ratio is 1.
5 times coating layer is formed, the size of the wooden molded product is 45m thick
m, 98 mm in width, 21 mm in width, 3 mm in depth as a sill groove, formed on the surface two grooves, and the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wood-formed product was 45%. Product was obtained.

Comparative Example 1 A conventional wood sill,
Wood with a thickness of 45 mm, a width of 98 mm, a length of 1800 mm, and two grooves having a width of 21 mm and a depth of 3 mm formed on the surface as sill grooves.

Comparative Example 2 1 part by weight of azodicarbonamide, which is a composition obtained by filling 50 parts by weight of wood powder of 100 mesh or less with 100 parts by weight of a polyvinyl chloride resin, was added to form a crosshead die having a threshold cross section. Using a vinyl acetate emulsion applied on the surface, thickness 40 mm, width 42 m
m, expansion ratio 1.5 on the outer peripheral surface of wood 1800 mm long
Double coating layer is formed, and the size of the wooden molded product is 45m in thickness.
m, 98 mm in width, 21 mm in width as a sill groove, 3 mm in depth, and 3 mm in depth, formed on the surface two grooves, and the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wood-formed product was 39%. Product was obtained.

Comparative Example 3 100 parts by weight of a polyvinyl chloride resin was added with 1 part by weight of an azodicarbonamide composition filled with 50 parts by weight of wood powder of 100 mesh or less, and a crosshead die having a sill-shaped cross section was prepared. Using a vinyl acetate emulsion applied to the surface, thickness 43mm, width 96m
m, expansion ratio 1.5 on the outer peripheral surface of wood 1800 mm long
Double coating layer is formed, and the size of the wooden molded product is 45m in thickness.
m, 98 mm in width, 21 mm in width as a sill groove, 3 mm in depth, 3 mm in depth, formed on the surface two grooves, and the ratio of the cross-sectional area of wood to the total cross-sectional area of the wood molded product was 96%. Product was obtained.

Comparative Example 4 1 part by weight of a composition, azodicarbonamide, filled with 100 parts by weight of polyvinyl chloride resin and 110 parts by weight of wood powder of 100 mesh or less was added, and a crosshead die having a sill-shaped cross section was prepared. Using a vinyl acetate emulsion applied to the surface, a thickness of 33 mm and a width of 90
mm, the expansion ratio is 1.
5 times coating layer is formed, the size of the wooden molded product is 45m thick
m, 98 mm in width, 21 mm in width as a sill groove, 3 mm in depth, and 3 mm in depth, formed on the surface two grooves, and the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wood-formed product was 70%. Product was obtained.

Table 1 shows the results of evaluation of the woody molded products of the examples and comparative examples by the following measuring methods and evaluation criteria. (1) Coefficient of linear expansion (1 / ° C) Amount of expansion and contraction (mm) with respect to temperature change from -20 ° C to 60 ° C
÷ 80 (° C.) ÷ 1800 (mm) <Evaluation criteria> 10 × 10 ^-6 or less: good ○ Exceeding 10 × 10 ^-6 : bad × (2) Load deflection (mm) Supported by a double-ended beam with a span interval of 900 mm Deflection amount when a center load of 15 kg is applied under the conditions <Evaluation criteria> 30 mm or less: good ○ Exceeds 30 mm: bad × (3) Warpage (mm) From the condition of absolute drying at 60 ° C to the condition of 90% relative humidity The amount of warpage changed <Evaluation criteria> 5 mm or less: Good ○ Exceeding 5 mm: Poor × (4) Surface appearance Wood texture by visual observation <Evaluation criteria> 4 or more in 5 grade evaluation: Good ○ 3 in 5 grade evaluation: Somewhat Defective で 2 or less in 5-grade evaluation: Defective ×

[Table 1] From Table 1, the outer surface of the wood was covered with a coating layer obtained by foaming a resin composition in which 100 parts by weight of synthetic resin was filled with 1 to 100 parts by weight of wood flour. A wood molded product having a ratio of 40 to 95% has a linear expansion coefficient of 10 × 10 ⁻⁶ or less, a weight deflection of 30 mm or less, and a warpage of 5 mm or less, which is excellent in strength and warpage and is visually observed. The wood texture is 4 on a 5-point scale
As described above, it can be seen that a molded article having a strength similar to that of natural wood and close to the texture of natural wood can be obtained.

[0017]

According to the present invention, it is possible to make a woody article such as a decorative panel such as a rim, a sill, furniture or the like in a house, and a wooden molded article such as an interior member of a vehicle close to the texture of natural wood. There is an advantage that the strength is the same as that and the warpage can be reduced.

Claims (1)

[Claims] 1. 100 parts by weight of synthetic resin and 1 to 100 wood flour
A wooden molded article in which the outer surface of wood is covered with a coating layer obtained by foaming a resin composition consisting of parts by weight, wherein the ratio of the cross-sectional area of the wood to the total cross-sectional area of the wooden molded article is 40 to 95%. Characteristic wooden molded products.