JPS6319328B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a synthetic resin molded article having a perforated metal plate attached to its surface.

A synthetic resin molded body with a metal plate attached to its surface is
Already known. However, most of the ones known so far did not have holes in the surface metal plate. In other words, synthetic resin molded articles with perforated metal plates attached to the surface and patterns created by the metal plates have not been produced until now. The reason is that it is cumbersome to attach a metal plate with holes and patterns to the surface of synthetic resin.
Also, it was not possible to firmly adhere the film. Therefore, perforated metal plates have been embedded inside resin moldings exclusively as internal reinforcing materials.

The inventor came up with the idea of attaching a metal plate with holes, thereby expressing a pattern, to the surface of a synthetic resin molded body, thereby expressing the pattern with the metal plate. We then investigated a method for firmly and efficiently attaching a perforated metal plate to the surface of a synthetic resin molded body.

In order to firmly attach a perforated metal plate to the surface of a synthetic resin molded body, it is conceivable to first make a synthetic resin molded body and then adhere or fuse the metal plate onto this surface. However, with this method, it is difficult to accurately position the metal plate on the synthetic resin molded body, and it is time-consuming and has problems in terms of efficiency.

The inventor came up with the idea of extruding molten resin onto a metal plate with a large number of holes, thereby integrating the metal plate with the resin. For this reason, the inventor placed a release sheet on a metal plate, covered the hole with the release sheet, closed the hole on one side only, and extruded resin around this, Later, I tried peeling off the release sheet from the metal plate to expose the metal plate. The results showed that it was possible to integrate the composite resin more efficiently than by making a synthetic resin molding and then bonding a metal plate on top of it.

However, it was found that simply covering the holes in a metal plate and extruding the coating around it did not allow the metal plate to adhere firmly to the synthetic resin, and therefore a good molded product could not be obtained. . As a result of further investigation, we found that if the edges of the holes in the metal plate were slightly bent into an arc shape against the synthetic resin, the metal plate and the synthetic resin would be firmly integrated during extrusion coating. I confirmed that it was reached. Furthermore, in order to facilitate the peeling of the release sheet, we learned that cuts should be made in the resin located on both side edges of the release sheet. This invention was made based on such knowledge.

The gist of the present invention is to use a metal plate in which a large number of holes are drilled, and the edge of the metal plate adjacent to the holes is slightly curved on the same surface. In addition, in this invention, a release sheet is brought into contact with the above-mentioned surface of the metal plate, the top of the hole is closed with the sheet, and the hole-blocking material obtained in this way is put into an extruder, and the area around the hole-blocking material is The main idea is to extrude coat the material. Furthermore, this invention covers the hole blockers with resin by attaching resin also on the release sheet, and provides a notch in the coated resin portion located at the edge of the release sheet to make the cut. The key point is to peel off the release sheet from the metal plate along the lines to expose the surface of the perforated metal plate.

This invention involves drilling a large number of holes in a metal plate, curving the edges of the metal plate close to the holes on the same surface, and applying a release sheet to the opposite side of the surface to form one end of the hole. The hole-blocking material obtained in this way is introduced into a crosshead die attached to an extruder and passed through, and the resin is extruded around the hole-blocking material in the die to form a release sheet. A resin molded body of a desired shape is formed on the side where no mold exists, and resin is also adhered onto the release sheet, and a cut is made in the resin located at the edge of the release sheet, so that the resin softens. The present invention relates to a method for manufacturing a synthetic resin molded article having a perforated metal plate attached to its surface, characterized in that a release sheet is peeled off from the metal plate while the metal plate is being heated.

An example of the implementation of the method of the present invention will be specifically explained with reference to the drawings as follows. In that case, FIG. 1 is a perspective view showing a part of the method of this invention, FIG. 2 is a partially enlarged view of the cross section taken along the line - in FIG. 1, and FIG. FIG. 4 to 6 are side views of an apparatus implementing the method of the invention. FIG. 7 is a partially cutaway enlarged perspective view of a synthetic resin molded article manufactured by the method of the present invention.

In this invention, a metal plate is used as one of the materials. The metal plate is perforated with a number of holes and the edges adjacent to the holes are curved towards the same surface of the plate. An example of such a metal plate is designated by the reference numeral 1 in FIGS. 1 and 2. In FIGS. 1 and 2, a metal plate 1 is provided with a large number of holes 11.
The total area of 1 covers more than one-third of the area of the original metal plate. In addition, the edge 12 adjacent to the hole 11
is slightly bent in an arc shape toward the lower side of the metal plate 1, and therefore curved in a convex shape toward the upper side of the metal plate 1. The degree of protrusion due to the curvature is greater than the thickness of the metal plate.

Metal plates include aluminum, stainless steel,
Plates made of various metals such as iron, copper, brass, silver, and gold can be used. Among them, aluminum is preferred. These metal plates are also perforated. Preferably, the holes are made by drawing and punching. This is because, with draw-cutting, the edge of the hole can be curved convexly toward the same plane at the same time as the hole is punched. The shape of the hole is arbitrary, and various patterns can be created by changing the shape of the hole.

As the metal plate, it is desirable to use a band-shaped body. Furthermore, when a band-shaped metal plate is used, it is desirable to leave ear portions on both sides of the metal plate in the longitudinal direction where holes are not made. Further, it is desirable that the surface of the metal plate 1 opposite to the side from which the edge 12 protrudes (hereinafter simply referred to as the surface) be painted. Also,
It is desirable to apply an adhesive to the surface of the metal plate 1 from which the edge 12 protrudes (hereinafter referred to as the back surface).

A release sheet 2 is brought into contact with the surface of the metal plate 1.
The release sheet 2 is made of metal foil, metal plate, synthetic resin,
A sheet made of paper, etc. is used. When a synthetic resin is used for the sheet, a synthetic resin that does not have adhesion or weldability to the extruded resin described later is used.
For example, when ABS resin is used as the resin for extrusion coating, polyester resin, fluororesin, etc. are used as the release sheet. These sheets are desirably coated with a release agent 21, such as silicone resin or fluororesin, on the surface that is to be in contact with the metal plate, and are desirably used in the form of a tape.

The release sheet 2 is brought into contact with the surface of the metal plate 1. At this time, the release sheet 2 is positioned so as to close the hole in the metal plate 1 only on one side. metal plate 1
When using a belt-like body with no holes left on both longitudinal edges of the belt-like body, as shown in Figure 1, the edges of both sides should be slightly away from the release sheet 2. It is desirable to abut the release sheet 2 away from both side edges of the metal plate 1 so that it is exposed.

As described above, the release sheet 2 is attached to the metal plate 1.
The pore-blocking material thus obtained is introduced into and passed through a crosshead die 3 attached to the extruder. That is, the hole blocker is advanced in the direction of arrow a, and the resin is coated around the hole blocker in the crosshead die 3. Coating the resin around the hole blockers within the crosshead die 3 is known as extrusion coating, and therefore detailed explanation will be omitted here.

The hole-blocking material extruded and coated in the nozzle 3 becomes an extrudate as shown by reference numeral 4 in FIG. 3, and is extruded from the nozzle 3 and advances in the direction of arrow b. However, in FIG. 3, part of the release sheet is peeled off to show the internal structure of the extrudate, but the part where the release sheet is actually peeled off is not at a position near the die 3. The extruded product 4 includes a metal plate 1 with a release sheet 2 in contact with the surface thereof, a molded body 5 made of extruded resin on the back surface of the metal plate 1, and a release sheet 2. A resin layer 6 made of extruded resin is also attached on top of 2 to form an integrated structure. The resin layer 6 does not need to be attached to the entire surface of the release sheet 2, but may be attached to at least both side edges.
In this way, the extruded product 4 has a structure in which the molded body 5 and the resin layer 6 surround and cover the metal plate 1 and the release sheet 2.

In the extruded product 4, cuts 7 are provided in the resin layer 6 located on both longitudinal edges of the release sheet 2. The cut 7 is for facilitating cutting between the resin layer 6 and the molded body 5, and is for facilitating cutting between the resin layer 6 and the molded body 5.
This is to make it easier to peel off the metal plate 1 from the metal plate 1.

After the extrudate 4 leaves the die 3, it is cooled to a state where it can maintain its shape without deforming itself, and then the release sheet 2 is peeled off from the metal plate 1.

The method of the invention is carried out as described above, and the entire process is illustrated in FIGS. 4-6. In FIG. 4, the perforated metal plate 1 is unwound from the roll 81, and the release sheet 2 is unwound from the roll 82 and is brought into contact with the surface of the metal plate to close the holes in the metal plate 1. The hole-clogging material thus obtained is introduced into a crosshead die 3 attached to an extruder 83, and is extruded and coated with resin within the die 3 to become an extrudate, which is then discharged from the die 3.
After the extrudate is cooled in a water tank 84, it is sandwiched between a pair of rolls 85, from which the release sheet 2 is peeled off, and then taken up by a take-up roll 86 and cut by a cutter 87 to remove the surface. A synthetic resin molded body with a perforated metal plate attached thereto is obtained.

The process shown in FIG. 5 is that the release sheet 2 is used in rotation as an endless belt.
This is different from the process shown in Figure 4. Specifically, the release sheet 2 is brought into contact with the surface of the perforated metal plate 1 and enters the crosshead die 3, becomes an extrudate 4, exits the die 3, and is then cooled in a water tank 84. ,
It is sandwiched between a pair of rolls 85, where the extrudate 4
The process is the same as that shown in FIG. 4 in that it is peeled off. However, the peeled release sheet is then further stripped of the resin layer 6 by the roll 88, leaving only the release sheet, and the direction is changed by the roll 89 to be reused. 4
The process is different from the one shown in the figure.

In the process shown in FIG. 6, a molded body having an irregular cross section is produced. The process shown in FIG. 6 is different in that a group of rolls 9 are attached after the release sheet 2 is brought into contact with the surface of the perforated metal plate 1 and before it is introduced into the crosshead die 3. Figures 4 and 5
The process is different from the one shown in the figure. The roll group 9 is for making the cross section of the hole-occluded material obtained by abutting the release sheet 2 against the metal plate 1 into an irregular shape. The process shown in FIG. 6 is different in that the release sheet 2 is left as it is without being peeled off, and is peeled off immediately before use.

In the method of this invention, various thermoplastic resins can be used for producing the molded body. For example, as described above, resins such as ABS resin, vinyl chloride resin, and olefin resin can be used.
These resins generally have poor adhesion to metals, so if particularly strong adhesion is required, an adhesive is used on the back side of the metal plate.

According to the method of this invention, a release sheet is brought into contact with the surface of a perforated metal plate to form a hole blocker, which is introduced into a crosshead die and penetrated, and a covering is formed by extrusion molding. Thereafter, simply by peeling off the release sheet, a synthetic resin molded body with a metal plate attached to the surface can be produced, so that the molded body can be manufactured efficiently and easily. Moreover, since we made a cut in the resin located at the edge of the release sheet,
The release sheet can be easily peeled off, and therefore a synthetic resin molded article having a metal plate attached to its surface can be manufactured more easily and efficiently.

Further, according to the method of the present invention, holes are made in a metal plate, the edges of the metal plate adjacent to the holes are made to protrude to the back side, a release sheet is brought into contact with the surface of the metal plate, and this is introduced into a crosshead die. Since the resin is extruded and coated by passing through the metal plate, the resin penetrates into the hole in the metal plate without knowing the back side, and as shown in Figure 7, the protruding edge of the metal plate sinks into the resin, and the resin surface is exposed to the metal plate. A product with a structure that is equivalent to or slightly concave is obtained. Therefore, the metal plate can be firmly integrated with the resin without using an adhesive, and even more firmly when an adhesive is used. Moreover, since the side edge of the metal plate facing the hole does not appear on the surface of the product, the product has a beautiful appearance. Furthermore, since the mold release sheet is also coated with resin and the mold release sheet is peeled off, the boundary between the resin and the metal plate is made clear, and the aesthetic appearance of the product is therefore improved.

As described above, the method of the present invention is excellent as a method itself, and also has the advantage of increasing the value of the product.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a part of the method of this invention, and FIG. 2 is a partially enlarged view of a cross section taken along the line - in FIG. FIG. 3 is a perspective view showing another part of the method of this invention. 4 to 6 are side views showing an embodiment of the method of the present invention together with an apparatus. FIG. 7 is a partially cutaway enlarged perspective view of a synthetic resin molded article manufactured by the method of the present invention.

Claims (1)

[Claims] 1. Drill a large number of holes in a metal plate, curve the edges of the metal plate close to the holes on the same surface, and press a release sheet on the opposite side of the above surface to cover only one end of the holes with the sheet. The hole-blocking material thus obtained is introduced into a crosshead die attached to the extruder and passed through, and the resin is extruded around the hole-blocking material in the die to form the resin on the side where the release sheet is not present. At the same time as forming a resin molded body of a desired shape, resin is also adhered onto the release sheet, and a cut is made in the resin located at the edge of the release sheet, so that the release sheet can be peeled off from the metal plate. A method for producing a synthetic resin molded body with a perforated metal plate attached to its surface.