JPH0143605B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a long article having a surface coating layer.

When forming a layer of a coating material such as a resin on the surface of a long object, such as a rod or a cylinder, an extrusion molding machine is generally used.

By the way, the above-mentioned coating layer tends to shrink when it cures, even if there are differences in the orientation and molding shrinkage rate of the material, and especially the shrinkage force in the longitudinal direction can cause shrinkage or the formation of wrinkles. There is a risk of inviting

In particular, the above problem becomes even more serious when the elongated object has a smooth surface or when the covering material is made of a non-foaming resin.

One solution to this problem is to prevent shrinkage of the surface coating layer, especially in the longitudinal direction, by forming a surface coating layer on the surface of a long object such as a rod via an adhesive layer. It is known that

However, with the above-mentioned means of interposing an adhesive,
Polyolefin resins such as polyethylene, which exhibit aversion to adhesives, cannot be used as the surface coating material. In other words, the selection of surface coating materials is limited by the adhesive. Regarding the adhesive itself, if it is solvent-based, the surface coating layer must be extruded while the adhesive is not dry, so the heat during molding evaporates the solvent, which causes the surface coating layer to be extruded. There is a risk that wrinkles may form in the layer, and therefore, it is inconvenient that only solvent-free adhesives can be used. Such problems are unavoidable as long as the above adhesive is used.

This invention was made in view of the above circumstances,
When forming a non-foaming resin coating layer on the surface of a long substrate having a smooth surface by extrusion molding, among the concave and convex lines extending on the surface of the substrate in a direction intersecting the longitudinal direction thereof. It is an object of the present invention to provide a method for manufacturing a long article that can prevent the shrinkage of the surface coating layer during curing by forming at least one of the following, thereby eliminating the possibility of wrinkles and the like. There is.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a rod obtained by the method for manufacturing a long article of the present invention, in which 1 is a base having a smooth surface, 2 is made of a non-foamed resin, and the surface of the base 1 is The formed surface coating layer 3 is a groove formed on the surface of the substrate 1.

The method for manufacturing the rod having the surface coating layer 2 is as follows.

First, on the surface of the base 1 having a smooth surface, a second
As shown in Figure A, grooves 3 such as V-shaped grooves are intermittently formed in the direction orthogonal to the longitudinal direction of the base 1, that is, around the axis of the base. The concave shape 3 is not limited to a V-shaped groove, but can be selected from other cross-sectional shapes such as a U-shaped groove.

After forming grooves 3 on the surface of the base body 1, the surface of the base body 1 is coated in a layered manner with a non-foaming resin coating material 2 using an extrusion molding machine M as shown in FIG. 2B. By curing the rod, a rod having a surface coating layer 2 as shown in FIG. 1 can be obtained.

Here, even if the surface coating layer 2 tends to shrink during curing, the grooves 3 formed on the surface of the base 1 have a function of fixing the base 1 to the coating layer 2 in the longitudinal direction. Therefore, the shrinkage in the longitudinal direction is prevented, and there is no risk of shrinkage or wrinkles.

Furthermore, since the surface coating layer 2 can be formed on the surface of the substrate 1 without using an adhesive, flexibility is given to the selection of the coating material.

In addition, in this example, the thickness of the portion of the surface coating layer 2 corresponding to the grooves 3 is large;
If a portion of the coating layer 2 is damaged over time, the spread of the damage is likely to be prevented by the thick portion, and therefore the area to be repaired can be minimized.

Furthermore, since the grooves 3 are arranged intermittently in the longitudinal direction of the base 1, it is easy to cut the rod into predetermined lengths. Therefore, it can be easily processed using cutting methods, for example.

By the way, in the above-described embodiment, the grooved stripes 3 are formed on the surface of the base body 1, but the grooved stripes 30 may be formed as shown in FIG. 3. This thing is
Since the thickness of the portion of the surface coating layer 2 corresponding to the ridges 30 becomes smaller, the thickness of the coating layer 2 decreases over time.
If a portion of the base body 1 is damaged, the damage will spread around the axis of the base body 1 along the ridges 30, and will be prevented from spreading to other parts. Therefore, only the damaged part can be cut out using the damaged part around the axis, and repair is easy in this case as well.

In addition, in the above embodiment, the concave or convex strips 3, 3
0 is formed around the axis of the base body 1 as an example, but these may be formed in any direction that intersects the longitudinal direction of the base body 1. For example, the grooves 30 in FIG.
They may be arranged in a spiral pattern extending in the longitudinal direction of the surface of the base 1, as shown in FIG. Of course, a configuration in which the grooves 3 and the protrusions 30 described above are combined is also possible.

As described above, in the present invention, prior to forming a non-foaming resin coating layer on the surface of a substrate having a smooth surface, at least one of concave and convex stripes is formed on the surface of the substrate, intersecting the longitudinal direction of the substrate. By forming one of them, shrinkage of the surface coating layer can be suppressed without using an adhesive, and the formation of wrinkles and shrinkage can be effectively prevented.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway sectional view showing an example of a long product obtained by the manufacturing method of the present invention, FIG.
FIG. 3 is an explanatory diagram of another embodiment of the present invention, and FIG. 4 is a perspective view of a long article base showing a modified example of the main part. be. DESCRIPTION OF SYMBOLS 1...Substrate, 2...Surface coating layer, 3,300...
...concave stripe, 30...convex stripe.

Claims (1)

[Claims] 1. When forming a non-foaming resin coating layer on the surface of a long substrate having a smooth surface by extrusion molding, concave and convex lines extending in a direction intersecting the longitudinal direction of the substrate are formed on the surface of the substrate. A method for manufacturing a long article, characterized in that at least one of the following is formed.