JPS624229B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a synthetic resin decorative board, which is characterized by excellent adhesion between the paint applied to the surface layer of the decorative board and the surface of the decorative board. This relates to decorative boards. [Prior art] Thermosetting synthetic resin decorative boards are generally used as surface materials for furniture and architectural interiors, and are usually combined with a decorative layer with an arbitrary pattern or color and various surface finishes such as brushed finish or embossed finish. , it can be finished into decorative boards with designs suitable for various uses. However, in recent years, thermosetting resin decorative boards obtained using the above production method have been combined with wood-based materials to produce low tables,
When manufacturing tables and other fixtures, as a final finishing step on the surface layer of each component after assembly, transparent uncolored or slightly colored urethane-based, acrylic-based, or aminoalkyd-based paints are applied. In recent years, a method has been adopted in which the surface layer of the thermosetting resin decorative board and wood is completely painted to give it a distinctive design. In such a production method, a thermosetting material obtained by a so-called normal molding method in which a metal backing plate or metal foil is directly contacted with the surface of coated or impregnated paper or cloth with a thermosetting synthetic resin and heated and pressurized. Even if a highly transparent paint like the one mentioned above is applied to the surface layer of a plastic decorative board,
The adhesion between the surface layer of the decorative board and the paint is insufficient, and the surface performance as a thermosetting resin decorative board, which is required in practice, has to be tested for water resistance, heat resistance, and cross-cut adhesion. It has been found that the coating film peels off easily in such cases, which poses a practical problem. As a means of improving these, in order to improve the adhesion between the surface layer of the decorative laminate and the coating film, the surface layer of the thermosetting resin decorative laminate is usually sanded and roughened to improve adhesion. It is well known that technical means such as measuring the However, when sanding is applied, the color and pattern of the printed layer used for the surface layer of the decorative board are worn away, causing the problem that the board loses its characteristics as a decorative board. Therefore, in order to improve these defects, it is necessary to apply acrylic, urethane, or aminoalkyd paint to the surface layer of the decorative board in advance to create a coating layer, or to coat the decorative board's printed paper (patterned paper). A special lightweight thin paper is used for the overlay layer to give the surface layer thickness.
A method is used in which the surface layer of the decorative board is sanded to roughen the surface and to prevent the pattern of the printed layer from disappearing, thereby obtaining the desired decorative board with excellent paint adhesion. The above method has enough paint adhesion to meet the required performance as a decorative board, but since it is necessary to create an overlay layer or a paint film layer, it is difficult to maintain the vivid color of a decorative board over all patterns. The problem arises that it is not possible to produce Furthermore, since sanding is required, the number of processing steps increases, resulting in various disadvantages such as not being economically advantageous. When molding a decorative board using a thermosetting resin such as an amino resin such as a melamine resin, an epoxy resin, a diallyl phthalate resin, or a polyester resin, the surface layer of the decorative board is made of stainless steel, duralumin, etc. Usually, the desired appearance is achieved by applying heat and pressure to the contact plate. In this case, it is in contact with the surface of the metal plate. Decorative board surface layer
When thermosetting resin is fluidized and hardened by heating and pressurizing at 100-200°C, it is molded into a very dense surface. In other words, depending on the ratio of the resin composition and the base material, paper or cloth,
It is finished in a resin-rich state, and if you observe the surface microscopically (observing the appearance using an electron microscope), you will find that it has a dense and smooth finish that cannot be said to have a decorative board appearance that can be expected to have the desired paint adhesion. It's summery. Therefore, there is almost no so-called anchor effect in which the resin-based paint adheres to or integrates with the surface layer of the decorative board, and peeling occurs even under normal conditions in the grid cut test, and it also peels off due to moisture absorption, water absorption, heating, and other external influences. , a phenomenon occurs in which the coating film easily peels off. [Object of the invention] The present invention has discovered a means of forming a surface layer with good paint adhesion by simply press-molding a thermosetting resin decorative board by heating and pressurizing it without performing secondary processing such as surface sanding. It is something that The appearance of the decorative laminate manufactured by the present invention was microscopically observed using an electron microscope, and during press molding by heating and pressurizing,
Various studies were conducted on a method of thermosetting the printed decorative paper used for thermosetting resin decorative boards while leaving the cellulose content exposed on the surface layer as much as possible. Basically, when the decorative laminate surface layer is hardened under pressure, the material in contact with the decorative laminate is softened by heat, and the thermosetting resin applied to and impregnated into the decorative laminate printing decorative paper/cloth becomes microscopic. It has been found that a method in which the material is cured while it is in an uneven state is desirable. [Structure of the Invention] At least the surface layer of the present invention is made of paper or cloth coated with or impregnated with a thermosetting synthetic resin mainly composed of an amino resin such as a melamine resin, a diallyl phthalate resin, a polyester resin, or an epoxy resin. Obtained by contacting a thermoplastic synthetic resin film or sheet with a melting point of 100 to 190°C to the surface of a heat-pressing type thermosetting synthetic resin decorative laminate material, performing high-temperature, high-pressure lamination molding, and then peeling off the film or sheet. This is a method for producing a surface-coated synthetic resin decorative board, characterized in that the surface of the decorative board having fine surface irregularities is coated with a solethane-based, acrylic-based, aminoalkyd-based, or polyester-based paint. In order to achieve this purpose, in contact with the decorative board surface layer,
Materials that regulate appearance, such as thermoplastic synthetic resin films or sheet materials, such as polypropylene, polyethylene, polyester, or vinylon, must be heated at 100°C.
A material that can be thermally softened is desirable. Polyurethane-based, acrylic-based, aminoalkyd-based, polyester-based, etc., paints are applied to the surface of the decorative board obtained by heating and pressurizing and molding using this method, and cured to produce a thermosetting resin with a painted finish. I got a decorative board. Adhesion of the surface layer of the decorative board was confirmed by a grid cut test. There was no difference in adhesion after immersion in a solvent and after water absorption as compared to room temperature, confirming that excellent properties were obtained for practical use. Next, a typical example will be described. Example 1 A decorative paper impregnated with melamine resin and dried by a conventional method, and core-impregnated paper obtained by impregnating and drying a phenol resin on kraft paper by a conventional method were used, and one piece of the melamine resin-impregnated decorative paper and the phenol resin-impregnated core were used. Multiple sheets of paper are laminated, a 20μ to 50μ polypropylene film (melting point 150 to 180℃) is placed on the surface layer of the melamine resin-impregnated paper, and a metal embossed backing plate is set on top of the melamine resin-impregnated paper at 160℃ and 100Kg/cm. ² for 50 minutes, and after cooling, the polypropylene film was peeled off to obtain the desired decorative board. The surface layer of the melamine decorative board thus obtained was spray painted with a 3-minute colored urethane resin paint (manufactured by Takashi Kubo Paint, OT, 696-6831) to obtain the final target decorative board. . The test results for the paint film adhesion of the decorative board are shown in Attached Table (1), and it has superior adhesion compared to a product press-molded with a duralumin backing board. Example 2 One sheet of decorative impregnated paper impregnated and dried with diallyl phthalate resin and one sheet of impregnated paper for the core, which was also prepared by impregnating diallyl phthalate resin into kraft paper and drying, were laminated, and a 20μ PE film (melting point
The film was heated and pressed at 135°C and 90 kg/cm ² and after cooling, the PE film was peeled off to obtain the intended decorative board. The decorative board was spray-painted with a urethane resin paint (Kansai Paint, AC Urethane Clear No. 611) to obtain a decorative board with a surface coating finish. The test results for paint film adhesion are shown in Attached Table (1). Comparative Example 1 Using decorative impregnated paper impregnated with melamine resin and dried, and core impregnated paper impregnated with phenol resin and dried, one sheet of the melamine resin impregnated paper and five sheets of phenol resin impregnated core paper were laminated, and duralumin made paper was laminated. The board was set on the surface layer of melamine resin-impregnated paper and molded under heat and pressure in the same manner as in Example 1 to obtain the desired decorative board. A urethane resin paint (OT696-6831, manufactured by Takashi Kubo Paint) was spray-coated on the surface layer of the decorative board in the same manner as in Example 1 to obtain a painted decorative board. The test results for paint film adhesion are shown in Attached Table (1). 【table】

Claims (1)

[Claims] 1 Heat-pressing type thermosetting synthetic resin in which at least the surface layer is coated with or impregnated with a thermosetting synthetic resin mainly composed of amino resin such as melamine resin, diallyl phthalate resin, polyester resin, or epoxy resin. A decorative board having fine surface irregularities obtained by contacting a thermoplastic synthetic resin film or sheet with a melting point of 100 to 190°C to the surface of a resin decorative board constituent material, performing high-temperature, high-pressure lamination molding, and then peeling off the film or sheet. A method for producing a surface-coated synthetic resin decorative board, which comprises applying a urethane-based, acrylic-based, aminoalkyd-based, or polyester-based paint to the surface of the laminate.