JPH0241136Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an ultraviolet curable FRP sheet with good processability and storage stability.

(Prior technology) Recently, as a new type of molding material, colorless and transparent polyvinyl alcohol is used to coat both sides of an uncured glass fiber-containing unsaturated polyester resin layer (hereinafter referred to as FRP layer) that can be cured by ultraviolet irradiation. A UV-curable FRP sheet covered with a resin film (hereinafter referred to as PVA film) has been developed.

This sheet is convenient because when it is bent into a desired shape and irradiated with ultraviolet light, the FRP layer quickly hardens and the desired molded product can be obtained, but it has the following problems.

(Problems to be solved by the invention) In other words, the ultraviolet curable FRP sheet is
Since the FRP layer is completely unhardened, it has the property of being soft and stiff. Therefore, for example, the seventh
As shown in the figure, even when obtaining a molded product with an extremely simple L-shaped cross section, the FRP sheet is
A mold 101 is required to maintain the L-shape of 00, and it is difficult to obtain a satisfactory molded product without such a mold 101. This was particularly a problem when molding to match the actual product at the construction site. Although this seems convenient, it is surprisingly inconvenient.

In addition, this sheet hardens in a short time when UV rays pass through the PVA film on both sides and hit the FRP layer, so it must be stored or transported in a UV-impermeable packaging bag such as a silver paper bag. There is also the inconvenience of not being able to do so.

The present invention aims to solve these problems.

(Means for solving the problem) For that purpose, the ultraviolet curing type according to the present invention
In the FRP sheet, both sides of the desired portion of the glass fiber-containing unsaturated polyester resin layer are coated with a removable UV-impermeable film. It has a structure in which it is a hardened part.

(Functions and Effects) When an ultraviolet curable FRP sheet having such a configuration is used, the cured portion of the FRP layer cannot be bent, and only the soft uncured portion can be bent. Therefore,
If only the parts that need to be bent in advance according to the desired molded product are made uncured parts, and the other parts are made hard parts, the shape-retaining mold 10 as shown in FIG. 7 described above can be formed.
1, it is possible to easily bend the uncured part, and in this folded state, the UV-impermeable film on both sides of the uncured part is peeled off and UV rays and sunlight are removed from the uncured part. When applied to the sheet, the uncured portion quickly hardens and the desired molded product can be obtained, resulting in much improved workability compared to conventional sheets.

Furthermore, since both surfaces of the uncured portion of such a sheet are covered with a UV-impermeable film, the uncured portion will not be cured by exposure to UV rays even in an unpackaged state. Therefore, unlike conventional sheets, there is no need to store them in ultraviolet blocking packaging bags, and they can be stored and transported as they are, which is very convenient.

Hereinafter, the present invention will be described in detail with reference to Examples.

(Example) Figure 1 shows the ultraviolet curable FRP according to the present invention.
FIG. 2 is a plan view showing an embodiment of the sheet, and FIG. 2 is a partially enlarged sectional view of the same embodiment, where 1 is an FRP
Both sides of this FRP layer 1 are covered with alternating wide strip-shaped ultraviolet-transmissive films 2, 2 and narrow-width strip-shaped ultraviolet opaque films 3, 3. The portion covered with the ultraviolet-transmissive films 2, 2 becomes a cured portion 11 that has been cured by receiving ultraviolet rays, and the portion covered with the ultraviolet-impermeable films 3, 3 becomes an uncured portion 12 that has not yet been cured. There is.

Such a sheet is easily manufactured by laminating an uncured FRP layer with ultraviolet ray transmitting films 2 and ultraviolet opaque films 3 arranged alternately on both sides and irradiating them with ultraviolet rays. Only the portion irradiated with ultraviolet rays through the ultraviolet transmissive film 2 is cured and becomes a cured portion 11, and the portion blocked by the ultraviolet ray impermeable film 3 is not cured and becomes an uncured portion 12.

This FRP layer 1 is mainly composed of unsaturated polyester resin, which is blended with glass fiber, an ultraviolet curing agent (e.g., disulfide-based curing agent), a diluent (e.g., styrene), etc. Similar to the FRP layer in FRP sheets, for example, FRP in PALAPREG LHZ (trade name of UV-curable FRP sheet manufactured by BASF)
The layers are partially cured as described above. The uncured part of the FRP layer 1 is soft and deformable, and the surface is sticky and sticky, but the cured part 11, which is partially cured by ultraviolet irradiation as described above, is strong. It becomes impossible to bend.

Both the ultraviolet-transmissive film 2 and the ultraviolet-opaque film 3 are adhered and laminated on both sides of the FRP layer 1 using the adhesiveness of its surface before partially curing the FRP layer 1 as described above. Since the ultraviolet transmitting film 2 is provided to eliminate the stickiness of the uncured FRP layer 1 and improve handling, it is possible to use various conventional transparent synthetic resin films (colorless transparent or colored transparent) that can transmit ultraviolet rays. ) can be used, and either one that adheres to the cured portion 11 or one that peels off as the FRP layer 1 is partially cured may be used. In addition, when using a peelable transparent synthetic resin film such as a polyvinyl alcohol resin film as the ultraviolet transmitting film 2,
After the FRP layer 1 is partially cured, the film is peeled off and the cured portion 11 is exposed.
For example, acrylic resin film, polyvinyl chloride resin film, fluororesin film, polycarbonate resin film, polystyrene resin film, polyester resin film, cellophane film, etc. It is desirable to cover and protect both sides of the cured portion 11 using an adhesive transparent synthetic resin film such as the above.

On the other hand, the ultraviolet opaque film 3 covering both sides of the unhardened portion 12 of the FRP layer 1 is provided to preserve the unhardened portion 12 without hardening until use. Various colored and opaque synthetic resin films containing large amounts of titanium powder or other pigments to block approximately 90% or more of ultraviolet rays, chemical paper, and single-sided adhesive silver paper are used. Since the ultraviolet opaque film 3 is adhered and laminated by the adhesiveness of the uncured portion 12 as described above, it can be peeled off.

In the ultraviolet curable FRP sheet having the above structure, both sides of the uncured portion 12 of the FRP layer 1 are covered with ultraviolet opaque films 3, 3, and ultraviolet rays do not hit the uncured portion 12, so unlike conventional sheets. It is possible to store it naked or transport it to the site without storing it in a UV-blocking packaging bag, etc., and it can also be made into a square corrugated board as shown in Figure 3 using the following procedure. Can be easily processed. That is, the sheet is bent at each uncured portion 12 to form a rectangular wave shape, and then the ultraviolet opaque film 3 covering both sides of the uncured portion 12 is peeled off to expose the uncured portion 12, and exposed to ultraviolet rays or The uncured portion 1 is irradiated with sunlight.
It is only necessary to harden 2. If the ultraviolet transmitting film 2 is the above-mentioned peelable synthetic resin film, by peeling and removing the film, a square corrugated plate having a single layer structure of only the FRP layer 1 as shown in FIG. 3 can be obtained. Further, when the ultraviolet transmitting film 2 is the above-mentioned adhesive synthetic resin film, only both surfaces of the cured portion 11 are covered with the film, resulting in a square corrugated plate.

When curing the uncured portion 12 indoors using an ultraviolet lamp or the like, one that emits ultraviolet light with a wavelength of 365 to 400 nm is preferably used, and the irradiation time depends on the thickness of the uncured portion 12. If it is 5 to 6 mm or less, it is sufficient to take several minutes.

As mentioned above, in the sheet of the embodiment shown in FIGS. 1 and 2, at least the uncured portion 12 of the FRP layer 1 is exposed after processing and is likely to deteriorate.In order to prevent this, the sheet shown in FIG. As in the embodiment, both sides of the entire FRP layer 1 are covered with UV-transparent films 2, 2 made of adhesive transparent synthetic resin films, and only the uncured portion 12 is further covered with UV-impermeable films 3, 3. It is preferable to configure With such a structure, it becomes a processed product with a three-layer structure in which both sides of the entire FRP layer 1 are covered and protected by the UV-transmitting films 2, 2 bonded thereto, which has the advantage of improved weather resistance. If an adhesive film with excellent weather resistance, such as an acrylic resin film, is used as 2, 2, the weather resistance can be significantly improved.

FIG. 5 is a perspective view showing another embodiment of the present invention. In this ultraviolet curable FRP sheet, both sides of a central flat uncured portion 12 covered with an ultraviolet opaque film 3 are exposed to ultraviolet rays. The hardened portion 11 is covered with the transparent films 2 and 2 and is shaped in advance into a corrugated plate shape. Such a sheet is used, for example, as a roofing material to cover the ridge of agricultural and horticultural greenhouses, etc., and the uncured portion 12 is bent on site to match the angle of the ridge.
All that is required is to peel off the ultraviolet opaque film 3 and irradiate the uncured portion 12 with sunlight to harden it, which is very convenient as it allows the angle to be adjusted freely on site.

Fig. 6 is a perspective view showing yet another embodiment of the present invention, in which this ultraviolet curable FRP sheet is shaped like an expanded rectangular box without a lid, and the bottom and four sides of the sheet are shaped like a rectangular box without a lid. The portion that is covered with an ultraviolet transmitting film 2 is a hardened portion, and the portion of the boundary line between the bottom surface and the four side surfaces is covered with an ultraviolet opaque film 3 and is a bendable uncured portion. and,
Overlapping allowances 4 are bent at right angles at both ends of a pair of opposing side wall portions, and fastener insertion holes 5 are formed at both end edges of these overlapping allowances 4 and the other pair of opposing side wall portions.
are drilled in multiple locations.

Such a sheet is made into a box shape by bending the uncured portion covered with the ultraviolet opaque film 3 at right angles, and fixing the sheet by inserting a stopper into the stopper insertion hole 5 so that the four side wall portions do not unfold again. Then, by simply peeling off and removing the ultraviolet opaque film 3 and leaving it in a place exposed to sunlight, the uncured portion will naturally receive ultraviolet rays and harden, forming a strong box, which is extremely convenient. It is.

[Brief explanation of drawings]

Fig. 1 is a plan view of an embodiment of the present invention, Fig. 2 is an enlarged partial sectional view of the same embodiment, Fig. 3 is a sectional view of a square corrugated plate obtained by processing the same embodiment, and Fig. 4 5 is an enlarged partial sectional view of another embodiment of the present invention, FIGS. 5 and 6 are perspective views of still another embodiment of the present invention, and FIG. 7 is an explanatory diagram of a conventional example. DESCRIPTION OF SYMBOLS 1... FRP layer, 11... Cured part, 12... Uncured part, 2... UV-transmissive film, 3... UV-impermeable film.

Claims (1)

[Scope of utility model registration request] Both sides of the desired portion of the glass fiber-containing unsaturated polyester resin layer are coated with a removable ultraviolet opaque film, and this coated portion is an uncured portion that has not yet been cured, and the other portion is a cured portion that has been cured by exposure to ultraviolet light. An ultraviolet curing type that is characterized by
FRP sheet.