JPH04187427A - Composite panel - Google Patents

Abstract

PURPOSE:To obtain a light composite panel capable of being inexpensively prepared and having high durability and suitable for various uses inclusive of a container material by forming a base film composed of a thermoplastic synthetic resin, a primer layer having weatherability and a surface protective layer composed of a cured resin on a wooden base material. CONSTITUTION:A polypropylene film is used as a base film 2 and a primer of a mixed resin system consisting of polymethyl methacrylate and a vinyl chloride/vinyl acetate copolymer is applied to the surface of the base film 2 to provide a primer layer 3. Polyester acrylate type ultraviolet curable paint containing benzophenone as an ultraviolet absorber is applied on the primer layer 3. This laminated film is passed under an ultraviolet lamp at a speed of 15m/min and the surface film of the curable paint is cured to form a protective layer 4. A polyamide adhesive is applied to plywood with 2.7nm thickness and the laminated film is laminated to the plywood so that the polypropylene film is turned downwardly. By this method, a composite panel can be inexpensively prepared without using a special material or apparatus.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a composite board used as a material for containers and as a building material for exterior and interior applications. [Prior Art] For example, a typical material for manufacturing containers is a steel plate coated with an appropriate coating. Containers made of steel plates have high strength and durability, but needless to say, they are heavy, difficult to handle, and relatively expensive. FRP board is known as a high-strength and lightweight material.
Because it is expensive, it can only be used for special purposes. The material used to easily manufacture containers is plywood laminated with polyvinyl chloride sheets.
However, this material is unsatisfactory in terms of the durability of the product container because the polyvinyl chloride sheet has poor weather resistance and heat resistance and has low surface hardness. (Problem to be Solved by the Invention 1) An object of the present invention is to provide a composite board that can be manufactured at low cost, is lightweight, and has high durability, and is suitable for various uses including container materials. Means for Solving the Problem] As shown in the drawings, the composite board of the present invention has a wooden base material (1)
Above, it comprises a thermoplastic synthetic resin base film (2), a weather-resistant primer layer (3), and a cured resin surface protection layer (4). Known plate-like materials such as plywood and particle board may be used as the wooden base material. It is preferable to select a base film that is inexpensive, easy to color or print, and has some degree of flexibility. Examples of such thermoplastic resin films include polyethylene, polypropylene, polyvinyl chloride,
Films of polyvinylidene chloride, polyvinyl alcohol, polyethylene terephthalate, polycarbonate, nylon, polystyrene, ethylene-vinyl acetate copolymer, (2) tyrene-vinyl alcohol copolymer, and ionomer. In particular, a polypropylene film is most suitable because cracks are unlikely to occur due to environmental changes. The thickness of the base film is 0.25-0.65N
ri is appropriate. The primer layer is preferably formed by applying a material with excellent weather resistance, such as a fluororesin, an acrylic resin, a mixture thereof, or polycarbonate, in the form of a paint. A crosslinking agent such as isocyanate may be added to the acrylic resin paint. It is a recommended embodiment to substantially improve weather resistance by incorporating a weather resistant pigment into the base film and/or primer layer. As weather-resistant pigments, quinacridone, isoindolinone, phthalocyanine blue, carbon black, etc. are known, and an appropriate one is selected from these for use. The cured resin forming the surface protective layer is a thermosetting resin or an ionizing radiation-curable resin. Examples of ionizing radiation-curable resins include oligomers such as epoxy acrylate, urethane acrylate, acrylic acid-modified alkyd, and acrylic-modified polyester, and neopentyl glycol diacrylate, etc. for the purpose of adjusting the crosslinking structure and viscosity. Pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolpropane
A mixture of monomers such as trimethacrylate is used. These can be sufficiently cured by electron beam, but when curing by ultraviolet irradiation, benzoin type, acetophenone type, benzyl ketal type, ketone/
It is common to add a photopolymerization initiator such as an amine type. In order to ensure adhesion to the base sheet, the intermediate layer, and even the protective layer, plastics of the same type or closely related to these may be added. Typical examples of ionizing radiation are electron beams and ultraviolet rays.
The former is emitted from various electron beam accelerators, and is 50 to 100
An electron beam with an energy key in the range 0 KeV, preferably 100 to 30 OKeV is used, the latter coming from a high-pressure mercury lamp or other ultraviolet source. Thermosetting resins include phenolic resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine/urea cocondensation resin, silicone resin, and polysiloxane. There are resins, etc.
If necessary, a crosslinking agent, a curing agent such as a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier, an extender, and the like are added. In order to impart weather resistance to the surface protective layer, it is preferable to add an ultraviolet absorber such as benzotriazole, benzophenone, finely powdered ferric oxide, finely powdered zinc white, or the like. However, when using an ultraviolet curable resin as the surface protective layer, the absorption wavelength band of the ultraviolet absorber is the wavelength band that degrades the cured resin, so as not to inhibit the curing of the resin.
It is necessary to select an ultraviolet absorber so that it is not substantially different from the wavelength band in which the resin is cured. - For example, when polyester acrylate resin is cured by ultraviolet light, the curing wavelength is centered around 254 to 360 nm, while the wavelength that degrades the facilitative resin is about 340 nm.
Since the wavelength range is 340 nm or more, an ultraviolet absorber having an absorption wavelength of 340 nm or more, such as benzophenone, is used. Generally, the surface protective layer has a thickness of about 10 to 15 μm to ensure its effectiveness. When a picture or pattern is provided on a base film or the like, the surface protective layer is formed of a colorless or colored transparent resin, but if not provided, the surface protective layer may be opaque. The surface of the protective layer can also be made matte. To make it matte, known methods such as adding a matte material to the resin or shaping the resin layer using a shaping film or an embossing plate may be used. The method for manufacturing the composite board of the present invention is arbitrary, and includes a step of sequentially laminating a base film, a primer layer, and a curable resin layer on a wood base material and curing the surface thereof. It can also be produced by applying a primer thereon, then applying a curable resin thereon and subjecting it to an appropriate curing treatment to obtain a laminated film, and pasting this onto a wood base material. [Function] By using a material with excellent weather resistance for the primer layer provided on the base film and using a cured resin with high surface hardness as the surface protective layer, the composite board has excellent weather resistance and scratch resistance. It gets expensive. These effects are ensured by the presence of a base film with appropriate flexibility.

[Example 1] A polypropylene film with a thickness of 0.25 m is used as the base film, and a mixed resin primer "D Primer" (manufactured by Moroboshi Ink) of boromethyl methacrylate and vinyl chloride-vinyl acetate copolymer is applied to the surface of the film. After drying, a primer layer was applied at a coating weight of 15 g/m. On top of that, a polyester acrylate-based UV-curable paint lN containing benzophenone as a UV absorber.
-1cKX-2J (manufactured by Dainichiseika Chemical Industry Co., Ltd.) was applied in an amount of 1'5 or 83/l after drying. This laminated film was heated for 15 minutes under an ultraviolet lamp (output 160 W/cm) consisting of four ozone-generating high-pressure mercury lamps.
It passed through at a speed of m/min to cure the curable paint film on the surface to form a protective layer. Apply polyamide adhesive on 2.7# thick plywood,
A composite plate of the present invention was obtained by laminating the above laminated films with the polypropylene film facing down. [Example 2] A polypropylene film with a thickness of 0.651110 was used as the base film, and a mixed resin primer "D Primer" of polymethyl methacrylate and vinyl chloride-vinyl acetate copolymer containing a metallic pigment was used on the base film (Moroboshi). A primer layer with a coating amount of 15!iF/m was applied and dried. On top of that, a polyester acrylate-based ultraviolet curable paint rH containing hensifhenone as an ultraviolet absorber was applied.
CKX-2J (manufactured by Dainichiseika Kagyo Kogyo) was applied so that the coating amount after drying was 129/㎜, and this film was passed under the same ultraviolet lamp as in Example 1 at a speed of 10 H/n+in. Provided with a protective layer. The above laminated film was coated on a wood base (
The composite board of the present invention was obtained by laminating the composite board on plywood.

【Effect of the invention】

The composite board of the present invention is light because it is made of wood and synthetic resin. Can be manufactured without using special materials or equipment,
It's cheap. It also has high durability. In addition to being suitable as a material for containers, this 'composite board can also be used as an interior or exterior building material, and has a wide range of uses.

[Brief explanation of the drawing]

The drawings are schematic cross-sectional views for explaining the present invention in detail. 1...Wood base material 2...-Base film 3.
・・Primer @ 4・・Surface protective layer patent applicant
Dai Nippon Printing Co., Ltd. Representative Patent Attorney Souo Suga

Claims (1)

[Claims] Thermoplastic synthetic resin base film on wood base material,
A composite board comprising a weather-resistant primer layer and a hardened resin surface protection layer.