JPS6123538B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for manufacturing a large reflective screen with special directivity, in which the joints are particularly inconspicuous, chemical changes are less likely to occur after adhesion, and manufacturing is simplified. .

As an example of a reflective screen, as shown in Fig. 1, a metal foil, for example, an aluminum foil 1, on which a reflective surface has countless elongated fine irregularities (wrinkles) extending in the vertical direction, is attached to a shape-retaining material 2, and the brightness is Some proposals have been made to improve this. Such a screen is said to have narrower directivity in the vertical direction than its directivity in the horizontal direction. As shown in FIG. 2A, this aluminum foil 1 is formed by pressing two aluminum foils 1 and 1' with rolling rollers 3a and 3b (the pressing surfaces are mirror-finished) and rolling them. , minute irregularities substantially perpendicular to the transfer direction are formed on the contact surface between the two. Then, as shown in FIG. 2B, this aluminum foil 1 is placed on a mold 4, its periphery is fixed with a frame 5, and the air is evacuated from a hole 6 provided in the mold 4 using a vacuum pump. Perform vacuum forming. Next, as shown in Figure 2C, with the aluminum foil 1 fixed on the mold 4, the FRP is inserted from the back side.
(Glass cloth impregnated with polyester resin) (trade name) 7 is applied and cured to complete the process. As the shape-retaining material 2, low-foaming polyurethane resin can be used,
In this case, as shown in FIG. 2D, the resin may be injected and molded using the upper mold 8.

The height h of such a screen is at most the width of the aluminum foil 1. As the width of this aluminum foil 1,
Currently, the maximum size that is easily available is 1250 (mm).

Therefore, if a screen with larger dimensions is to be manufactured, it is necessary to bond two or more sheets of aluminum foil together. As a method, Figure 3A
As shown in FIG. 2, a method is conceivable in which two screens each having shape-retaining materials 2a and 2b adhered to aluminum foils 1a and 1b are brought together and bonded together using a single-sided adhesive tape 9. According to this method, the joint becomes wider, and as shown in FIG. 3B, the end of the joint swells up, making it impossible to form a correct spherical shape.

Further, as shown in FIG. 4A, the end surfaces of the two aluminum foils 1a and 1b are brought together in advance,
Paste together with single-sided adhesive tape 9 and attach it as shown in Figure 2B.
A conceivable method is to place it on a mold in the same manner as above, perform vacuum forming on the mold, and then apply a synthetic resin material in this state. In this method, since tension is applied to the aluminum foil during vacuum forming, misalignment occurs between the aluminum foils 1a and 1b and the adhesive surface of the single-sided adhesive tape 9, as shown in FIG. This occurs, and this opening 10 appears as a black line, and
This has the disadvantage that the components of the single-sided adhesive tape 9 seep out, and since the aluminum foils 1a and 1b are very thin (30μ), it is difficult to bring them together. Therefore, when the aluminum foils 1a and 1b are butted together, as shown in FIG.
A manufacturing method in which the aluminum foil 1b is cut along an arrow is considered, but there is a problem in that the reflection characteristics of the cut surface of the aluminum foil 1b change due to curling or meandering, and the seam becomes noticeable depending on the viewing angle. Furthermore, in the manufacturing method shown in Fig. 4, the single-sided adhesive tape 9 and the synthetic resin material such as FRP come into contact with each other, causing chemical interference between the two, resulting in loss of uniformity of the single-sided adhesive tape 9, and unevenness on the reflective surface. may occur.

In view of the above-mentioned points, the present invention aims to provide a method for manufacturing a large-sized screen in which joints are less noticeable, chemical changes after adhesion are less likely to occur, and manufacturing is easy.

Hereinafter, to explain one example of the present invention, the fifth
In the figure, 1a and 1b are aluminum foils with minute irregularities extending in the vertical direction, as described above.
2 is a shape-retaining material. The height h' of the screen is, for example, 1800 (mm), and the width W is 2400 (mm).
The manufacturing process of the screen of this example consists of a process of bonding two sheets of aluminum foil 1a and 1b, a process of vacuum forming, and a process of applying a shape-retaining material. When pasting the aluminum foils 1a and 1b together, as shown in FIG. 5B and C, double-sided adhesive tape 11
Use. That is, the respective ends of the aluminum foils 1a and 1b are arranged and bonded to both adhesive surfaces of the double-sided adhesive tape 11 so as to partially overlap with each other. in this case,
The aluminum foil 1a located on the reflective surface side of the bonded portion is bonded so that its end surface protrudes by, for example, about 1 mm (see FIG. 6). The double-sided adhesive tape 11 is a non-hardening material that does not become hard after adhesion, and has viscosity and ductility. Therefore, it can follow the elongation when the aluminum foil is pulled during vacuum forming, and due to this elongation. The edges of the portions that were protruded during bonding are aligned with the edges of the double-sided adhesive tape 11 as shown in FIG. 5C. For example, the double-sided adhesive tape 11 has a thickness of 20 to 25 mm.
(μ), and the width is 30 to 100 (mm). Also,
As for the double-sided adhesive tape 11, it is preferable to use only an adhesive layer rather than having an adhesive layer provided on both sides of the base, since this prevents the base from being misaligned with the adhesive layer.

According to the present invention described above, it is possible to obtain a large screen with a height greater than the maximum width of aluminum foil.
Then, the seams of the screen are shown in Figure 3 or Figure 4 A and B.
It can be made less conspicuous than the screen obtained by the manufacturing method shown in . Furthermore, according to the manufacturing method shown in FIG. 4, there is a risk that chemical interference may occur due to contact between the adhesive tape and the shape-retaining material, resulting in unevenness on the reflective surface. Since the adhesive tape 11 is covered with the aluminum foils 1a and 1b, there is almost no chemical interference between the two. Furthermore, since the end faces of the aluminum foils 1a and 1b are not brought into contact with each other, it is easy to manufacture and has the advantage of high mass productivity, and there is no gap between the end faces after vacuum forming.

In addition, the double-sided adhesive tape only needs to have adhesiveness and ductility at least during molding.For example, a thermosetting double-sided adhesive tape is used, vacuum forming is performed after the pasting process, and in that state, double-sided adhesive tape is used. The tape may be heated and cured, and then FRP may be applied. According to this manufacturing method,
It takes a long time for FRP to harden (about 6 hours), which has the advantage of preventing the bonded part from shifting during that time.

In the above description, the reflective surface is a spherical surface, but even if the reflective surface is a flat plate, the same benefits can be obtained by applying the present invention since the reflective surface is usually applied with tension or pressed. Moreover, not only vacuum forming but also press forming and roll forming may be used.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an example of the screen, FIG. 2 is a diagram showing its manufacturing process, and FIGS. 3 and 4 are diagrams used to explain several methods of manufacturing the screen.
FIG. 5 is a plan view, a sectional view, and a partially enlarged sectional view of an example of the present invention, and FIG. 6 is an enlarged sectional view of the present invention. 1, 1a, 1b are aluminum foils with directivity,
2, 2a, and 2b are shape-retaining materials, and 11 is a double-sided adhesive tape.

Claims (1)

[Claims] 1 At least two directional metal foils,
The ends of each of the metal foils are arranged so as to partially overlap, and an adhesive material having adhesiveness and ductility is interposed between the overlapping parts of each of the metal foils at least during molding. Glue the ends of the foil so that the metal foil located on the reflective surface side protrudes a little extra at the bonded portion, and place each of the bonded metal foils on a mold having a convex surface. Then, by vacuum forming, each of the metal foils is stretched at least in a direction perpendicular to the extension direction of the bonded portion to form a convex shape, and the back surface of each of the metal foils formed into a convex shape has a shape-retaining material. A manufacturing method for large screens that use common materials.