JP3058987B2 - Manufacturing method of artificial bamboo - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method for producing a knotted pseudo bamboo material obtained by coating a thermoplastic core material with a molten plastic material.

[0002]

2. Description of the Related Art Various methods for producing plastic artificial bamboo used mainly for agricultural and horticultural use or for landscaping are known. For example, Japanese Patent Publication No. 54-28441 and Japanese Patent Publication No. 54-37823 relating to the invention and device of the present applicant.
And JP-A-55-150327.

[0003] Natural bamboo materials are classified into male bamboo and female bamboo. Among them, male bamboo has a high knot as shown in FIG. The outer diameter of the bamboo is slightly narrower toward the center, whereas the female bamboo has a lower knot as shown in FIG. The feature is that it does not.

[0004]

In the above-mentioned conventional techniques for producing a pseudo-bamboo material of this kind, there is no distinction between male bamboo and female bamboo, that is, the height of the nodes and stems is constant, and Because of the straightness, no matter how the color was applied, there was a problem that the texture was significantly different from that of a natural bamboo material, so that the material did not go out of the pseudo-bamboo area.

[0005]

Means for Solving the Problems The present inventor has intensively conducted experiments and improvements in order to solve the above-mentioned problems in the prior art, and has arrived at the present invention. That is, while the tubular core material is sent out from the die opening of the extruder at a constant speed, a molten plastic material of one or two colors for a light ground color film and / or a dark color pattern film is coated on the core material surface. In the method of manufacturing a pseudo-bamboo material in which the knots are raised by stopping the sending of the core material at a fixed time interval while wearing,
In the production of Otake, a core made of a thermoplastic plastic material with a relatively low melting point is used as the core material, and only the nodes raised at regular intervals by the molten plastic material are cooled and hardened on the surface of this core material, so that it can be used before and after. The so-called stalks between the nodes of the stalks were extended and the outer diameter was gradually reduced toward the center.

In the above-mentioned conventional method for producing artificial bamboo material, when producing female bamboo, a tubular body made of a thermoplastic material of the same quality as that of male bamboo is used as a core material,
By means of cooling and hardening only the stalks between the nodes before and after being raised at regular intervals on the surface of the core material, a method of extending the nodes and reducing the diameter was used.

[0007]

According to the present invention having the above-mentioned structure, according to the first aspect of the present invention, the node raised by the molten plastic material at the exit of the die opening is cooled and hardened by water or cold air.
Since the core material is also softened by the latent heat of the molten plastic material that has been spread between the other stem portions, that is, between the front and rear nodes, this portion is extended by receiving the pulling force of the front draw-out roller, and this extension is accompanied by this extension. The outer diameter of the stalk gradually decreases toward the center, and the diameter difference between the stalk and the node, which is hardened by the reduced diameter of the stalk and is not affected by the pulling force of the pull-out roller, is increased. It has a special effect of giving the texture of Otake.

According to the second aspect of the present invention, contrary to the above case, only the stem between the nodes after the molten plastic material is cooled and hardened. Although the part does not stretch, the uncooled nodes are stretched by the tensile force of the roller because the core material is also softened by the latent heat of the melted plastic material that has been laid and raised, and the outer diameter is commensurate with that. Because it decreases
This has the effect of reducing the volume of the knots and obtaining the texture of female bamboo.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of the present invention will be described below in more detail with reference to the drawings shown in the embodiments. FIG. 1 shows an embodiment relating to a bamboo bamboo-like material, and FIG. In each of the figures, reference numeral 1 denotes a commonly used double-extrusion extruder, 2 denotes a die port of the extruder, 3 denotes a cooling device provided facing the die port 2, and 4 denotes a relatively low melting point. A core material made of a plastic material, and further, 5.5 ′ denotes a two-color plastic film deposited on the surface of the core material 4.

Although the cooling device 3 is most effective by jetting cold water or cold air, other means may be used. Alternatively, a two-color plastic material coated on the core material 4 may be used. The coating 5,5 'is a ground color coating 5 of natural bamboo such as light green (raw bamboo) or light yellow (dead bamboo).
And a pattern film 5 'on the upper layer, which is applied so that the color tone gradually decreases from the node 6 toward a subsequent node (not shown). Since the elevating means and the like are already known technologies by the present applicant, their descriptions are omitted in this section.

In FIGS. 1 and 2, 8.8 'is a resin chamber separated into two shades of light and shade, 9 is a cylinder for extruding a resin for a ground color coating, and 10 is an extrusion cylinder for a resin for a pattern coating. As shown, these devices are mechanisms known as extruders.

First, a method of manufacturing a bamboo-like artificial bamboo material will be described with reference to FIG.
Is instantaneously cooled and hardened by the cooling device 3,
The stem 7 between the front node 6 'and the core 6 is sufficiently softened by the latent heat of the applied film, so that the product is moved in the axial direction (arrow) slightly faster than the feeding speed of the core 4. The stem 7 is elongated by the action of a pulling roller (not shown) that pulls out the core material 4 and the core material 4 is gradually reduced in diameter with the film toward the center of the stem, and is already hardened and deformed. The difference in diameter from the nodal section is increased, giving the texture of Otake.

Next, a method of producing a female bamboo-like artificial bamboo material will be described. The film of the stem 7 following the front node 6 ′ raised by the molten plastic material at the exit of the die opening 3 is sequentially cooled by the cooling device 3. If the core 4 is cooled and hardened and only the subsequent node 6 is left uncooled, the core material 4 in this portion is softened by the latent heat of the molten plastic material applied to the node 6, so that the delivery speed of the core 4 is The node 6 is extended by the action of the pulling force of the pull-out roller, which pulls out the product in the axial direction at a slightly faster speed, and its core material is shrunk in the inner diameter direction together with the film, and is already hardened and deformed. The diameter difference from that of No. 7 is reduced, and the texture of female bamboo can be easily expressed.

In the above two methods, the case where the core material 4 is insufficiently softened only by the latent heat of the portion of the plastic film which is not cooled and hardened, and the portion 6 or 7 cannot be extended even by the pulling force of the drawing roller. In some cases, the core material 4 in this portion may be separately heated and softened so that it can be extended.

[0015]

As described above, the artificial bamboo material of the present invention has a body shape which is not uniform as in the prior art, but is a natural bamboo material, especially a male bamboo which requires a complicated shape. Can be easily produced by conventional molding equipment, and if it is subjected to a coloring process such as raw bamboo or dead bamboo using the conventionally known coloring technique, it more closely resembles natural bamboo. The remarkable effect that the artificial bamboo can be mass-produced economically is obtained.

In addition, in the shortage of forest resources as in recent years, the real orientation at the consumer stage is no exception in fields such as horticulture and landscaping. With the satisfaction of consumers in these areas,
If the sluggish demand in recent years can be alleviated or eliminated, its effectiveness will be even more remarkable.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of an extrusion molding machine showing a process of manufacturing a bamboo-like artificial bamboo material according to the present invention.

FIG. 2 is a longitudinal sectional view of an extrusion molding machine showing a process of manufacturing a female bamboo-like artificial bamboo material according to the present invention.

FIG. 3 is a partial front view showing a form of a natural bamboo.

FIG. 4 is a partial front view showing a form of a natural female bamboo.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 extruder 2 die opening 3 cooling device 4 core material 5 ・ 5 ′ plastic material 6.6 ′ node 7 stem 8.8 ・ 8 resin chamber 9.110 Extrusion cylinder for ground color / pattern coating

Claims (2)

(57) [Claims] (1) While feeding a tubular core material from a die opening of an extruder at a constant speed, a molten plastic material is put on the core material surface, and the core material delivery is stopped at a constant time interval. In a method of manufacturing a pseudo-bamboo material having raised nodes, a core made of a thermoplastic material having a relatively low melting point is used as a core, and the nodes raised on the surface of the core at regular intervals are cooled and hardened. The method according to claim 1, wherein the stem between the nodes is extended. 2. A die of an extruder for extruding a tubular core material at a constant speed.
The molten plastic material is removed from the core
Stops sending core material at regular time intervals while attaching to the surface
How to manufacture pseudo-bamboo lumber with raised joints
In the method, a tubular body made of a thermoplastic material having a relatively low melting point is used as a core material, and only the stems between the nodes that are raised at regular intervals on the surface of the core material are cooled and hardened to extend the nodes. A method for producing a female bamboo-like artificial bamboo material, characterized in that: