JPS6215324B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] This invention relates to a method for producing artificial bamboo that can be used as a building material.

[Background technology]

Conventional artificial bamboo made from synthetic resin foam is made by injecting foamable colored urethane resin 4 from a single nozzle 3 into the mold frame of a silicone rubber mold 2 in a lower mold 1 as shown in FIG. 1, for example. However, after the upper mold 5 was overturned, it was manufactured by foaming and curing it.

However, because the artificial bamboo produced in this way has a uniform surface, it does not have stripes of subtle color shading along the length or dark colored protruding knots that are found in natural bamboo. It lacked a natural feel.

[Purpose of the invention]

An object of the present invention is to provide a method for producing artificial bamboo that has a color similar to that of natural bamboo and is rich in natural appearance.

[Disclosure of the invention]

The method for manufacturing artificial bamboo of the present invention is to mold colored foamable resin along the longitudinal direction of a concave mold surface provided on the upper surface of a lower mold and having a cross-sectional arc shape and horizontal grooves for forming knots extending in the width direction. After injecting in stripes at appropriate intervals in the width direction of the surface, an upper mold is placed on the lower mold surface to foam the foamable resin, forming a large number of fine shading stripes in the longitudinal direction. It is also characterized by forming dark-colored knot-like protrusions in the width direction.

In this way, according to the present invention, the colored foamable resin is injected into the concave mold surface in a striped manner, so that the density of the resin after foaming becomes uneven in a striped manner, and areas with high density become dark colored and Areas with low density become lighter in color, creating a striped shading pattern on the surface. In addition, the colored foamable resin injected into the horizontal grooves provided on the recessed mold surface is not sufficiently foamed in that area even during foaming treatment, resulting in high density, so dark knots may not be formed. This, combined with the striped shading pattern described above, results in a beautiful appearance that closely resembles that of natural bamboo.

Embodiment An embodiment of the present invention will be explained with reference to FIGS. 2 to 8. That is, the lower mold 6 used in this example
A silicone rubber mold 7 with an arc-shaped cross section is set in
As shown in FIG. 2, a transverse groove 8 is provided across the middle part of the longitudinal direction, and while the fan-shaped nozzle 9 provided above is moved along the longitudinal direction, appropriate intervals are formed on the arcuate surface of the sector-shaped nozzle. Colored foamable resin (urethane resin, etc.) is ejected from the pores 10 arranged at intervals.
Inject 11. After arranging the colored foamable resin 11 in stripes at appropriate intervals as shown in FIG. 3, the upper mold 12 is overturned and foamed as shown in FIG. 4. Artificial bamboo 13 made of hard foam Manufacture.

As shown in FIG. 5, the artificial bamboo 13 manufactured in this way has uneven density in the striped areas where the colored foamable resin 11 is injected, as shown in FIG. is dark in color, and the low-density portion b is pale in color, creating a striped shading pattern. Furthermore, even if the colored foamable resin 11 injected into the horizontal grooves 8 of the silicone rubber mold 7 as shown in FIG. The density is higher than that of part b, and as a result, this part a has a dark color.

The obtained artificial bamboo 13 is shown in FIG. In this artificial bamboo 13, fine irregularities are further provided along the longitudinal direction of the silicone rubber mold 7, and a large number of fine colored stripes and irregularities are formed in the longitudinal direction of the surface 15, and dark colored stripes and irregularities are formed in the horizontal direction. Since the knot-like protrusions 16 are formed, the synergistic effect of these protrusions makes the appearance as beautiful as that of natural bamboo. Moreover, when a green colored urethane resin is used as the colored foamable resin 11, the surface turns yellow over time, and it is possible to obtain a change in color tone that is exactly the same as that of natural bamboo.
In addition, the striped pattern has a deep color due to the change in density of the foam, and the surface has striped irregularities, so the shading effect creates an excellent texture and three-dimensionality that cannot be obtained with conventional printing. I can express my feelings. Furthermore, it is convenient for construction if a tongue-and-groove fitting mold (not shown) is attached to both sides of the silicone rubber mold 7 to provide a male groove 14 and a female groove 14a on both sides of the artificial bamboo 13. be.

In addition, the outer surface of the artificial bamboo is made into a sheet-like material made of a transparent synthetic resin, and appropriate grooves are provided on the inner surface of the sheet-like material, and the grooves are densely filled with a colored foamable resin composition. You may. Furthermore, when manufacturing artificial bamboo, it is also possible to use foamable resin mixtures with different foaming properties to foam the bamboo to form a patterned material.

〔Effect of the invention〕

According to this invention, colored foamable resin is injected into the concave mold surface in stripes, so the density of the resin after foaming becomes uneven in stripes, with areas of high density becoming dark colored and areas of low density. becomes lighter in color and can create a striped shading pattern on its surface. In addition, the colored foamable resin injected into the horizontal grooves provided on the recessed mold surface is not sufficiently foamed in that area even during foaming treatment, resulting in high density, which prevents the formation of dark knots. This, combined with the striped shading pattern described above, results in a beautiful appearance that closely resembles that of natural bamboo.

[Brief explanation of the drawing]

FIG. 1 is a perspective view for explaining the conventional method;
Fig. 2 is a perspective view illustrating an embodiment of the method of the present invention, Figs. 3 and 4 are explanatory diagrams each using a cross section of Fig. 2, and Fig. 5 is a partially enlarged view of Fig. 4. 6 and 7 are explanatory diagrams using the longitudinal section of FIG. 2, respectively, and FIG. 8 is a perspective view showing the obtained artificial bamboo. 6...Lower mold, 7...Silicone rubber mold, 8...
...Horizontal groove, 9...Sector nozzle, 10...Small hole, 11
...Colored foamable resin, 13...Artificial bamboo, 16...
Nodular prominence.

Claims (1)

[Claims] 1. Colored foamable resin is applied at appropriate intervals in the width direction of the mold surface along the longitudinal direction of the recessed mold surface provided on the upper surface of the lower mold, which has an arc-shaped cross section and a lateral groove for forming knots extending in the width direction. After injecting the resin in stripes, an upper mold is placed over the lower mold surface to foam the foamable resin, forming many finely shaded stripes in the longitudinal direction and dark nodules in the width direction. A method for producing artificial bamboo, characterized by forming protrusions.