JPS63234B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a decorative board using melamine resin impregnated paper. More specifically, the present invention relates to a method for manufacturing a melamine decorative board having a surface with a three-dimensional effect due to unevenness or gloss differences that match the pattern. In the past, many proposals have been made regarding the production of decorative laminates that have an uneven surface that matches the pattern, but it is possible to change the conventional process by delaying the hardening of the impregnated resin only in specific pattern areas. The method of obtaining a three-dimensional effect that is almost in sync with the pattern would be a very attractive method if it could be done stably. The present inventors first developed a method using an ink containing a basic substance that is solid at room temperature and has virtually no water solubility, such as an alkaline earth metal hydroxide, as an ink that delays curing, and as a binder. An application has been filed for a method using a partially crosslinked polyurethane resin to peel off only the interlayers of the resin layer in areas where curing is delayed, creating recesses in those areas and eliminating the luster, but these methods have been further investigated. As a result, they completed an invention for an improved method for more stable production. A substance that is solid at room temperature and has virtually no water solubility is used as a substance that delays the curing of melamine resin.
By dispersing this in ink, it can be used as pattern ink for concave or matte parts of products, especially to prevent the pattern from bleeding during the impregnation and pressing process, suppress changes in the impregnating liquid PH, It is characterized by being able to form embossed areas stably and sharply, but on the other hand, in order to achieve the effect of basic substances, a large amount of powder is mixed into the ink, or the amount of ink applied is larger than usual. However, it was not completely satisfactory, especially from the viewpoint of printing suitability and not reducing the efficiency of actual production. In order to achieve printability, especially sufficient ink transferability, it is clear that it is not desirable to add a large amount of powder that reduces the strength within the layer during ink transfer, but conventional methods, For example, there is a limit to the improvement of printability by improving the binder, and there is no suitable method that does not reduce the heat-resistant interlaminar strength required during pressing. The present invention has been made in view of these points, and in order to reduce the necessary amount of a basic substance that is solid at room temperature and is contained in an ink that delays curing without reducing the embossing effect, it is possible to use a relatively coarse basic substance that is solid at room temperature. By using a filler containing a grain component in combination, it is possible to reduce the adhesion between the basic substance particles and the surface coverage by the binder, thereby increasing the effective surface area of the basic substance. The filler used for this purpose varies depending on the size and shape of the particles, but those with too large a particle size are unsuitable as an ink component, and those with a small particle size are not only used to fill voids but also This is also unsuitable as it causes an increase in viscosity. As a result of the study, the most effective particle size was found to be an average particle size of 2.
It was found that a range of ~20μ is appropriate. Regarding the chemical composition of the filler, considering the purpose, water-soluble and strongly acidic ones are excluded, but it is arbitrary as long as it is chemically relatively inert and dispersible.
Commonly available minerals such as aluminum hydroxide, calcium carbonate, barium sulfate, and talc can be used, but silicon dioxide powder is particularly suitable for this purpose. The amount of filler added is preferably about the same volume ratio as the basic substance; if the amount of filler added is too large, printability, which is the intended purpose, will be inhibited. Materials other than the filler used in the present invention may be those normally used for manufacturing melamine decorative boards, and in particular, the base paper, pattern ink other than the part forming the recesses, impregnating resin, base material, etc. There is no limit, but when used in combination with a resin with high heat resistance such as urethane as a binder for ink that delays curing, it is important to avoid peeling between the resin layers in areas where curing is delayed during press release. By using a mechanism that simultaneously removes the board and attaches a portion of the resin to the forming plate, it is possible to continuously create melamine decorative boards with an embossed surface that matches the pattern without having to clean the forming plate. It is very advantageous in terms of work as it can be made easily. Next, examples of the present invention will be described, but the present invention is not limited to the following examples unless it departs from the spirit thereof. [Example 1] A wood grain background pattern was printed on 80 g/m ² titanium-containing paper using normal ink with a cellulose binder,
Furthermore, after printing the conduit handle using the following inks 1 and 2, impregnating it with the following melamine resin 1,
By drying at 120°C for 5 minutes, a mixed paper with a mixed resin ratio of 60% was prepared. This was placed on a particle board with the printed side facing up, a forming plate was applied, the top and bottom of the whole was sandwiched between cushioning materials, and after pressing at 145°C and 15 kg/cm ² for 5 minutes, the forming plate was removed and allowed to cool. As a result, ink 2 removes the decorative board from which the conduit part has partially peeled off in the ink layer, and ink 1
Thus, a beautiful decorative board was obtained in which the conduit portion had a concave portion where the ink layer was peeled off as a whole.

[Example 2]

After printing a wood grain background pattern on 80g/ ^m2 titanium-containing paper using regular ink with a cellulose binder, a gravure conduit plate (screenless) with a plate depth of 60μ was used to achieve the same embossing effect with the same amount of ink. The following ink 3 and ink 4 were printed. Ink 3 could be printed normally, but ink 4 had unstable transfer of the conduit stem. Impregnated paper was prepared in the same manner as in Example 1, and pressed into a decorative board.
Ink 3 was used to obtain a beautiful decorative board in which the surface resin layer of the conduit part was peeled off, the conduit part became a concave part, and the gloss had disappeared. Furthermore, when the forming plate used at this time was used in the pressing process of melamine mixed paper, no traces of conduits were left behind on the surface of the subsequent decorative board. On the other hand, those using Ink 4 were partially embossed, but the design was insufficient.

【table】 [Brief explanation of the drawing]

The drawings are schematic diagrams showing the steps of the present invention, and the case of Example 2 is shown as an example. FIG. 1 is a cross-sectional view of the mixed paper, FIG. 2 is a cross-sectional view of the product before pressing, and FIG. 3 is a cross-sectional view of the product after being taken out from the press. 1... Impregnated resin, 1'... Impregnated resin on the ink that retards the curing of the resin, 1''... Impregnated resin attached to the forming plate, 2... Ink that delays the curing of the resin, 3... Normal ink, 4...Base paper, 5...Substrate, 6...Formation plate, 7...Cushion material, 8...
Hot plate.

Claims (1)

[Scope of Claims] 1 A pattern paper for impregnation with an ink layer that delays the curing of the impregnated resin is impregnated with melamine resin, and after drying, the paper is overlapped with the substrate and a molding plate is applied to the paper and heated and pressurized to delay the curing. In the manufacturing method of melamine decorative board, which makes the surface condition of the exposed part different from other parts, the ink contains a basic substance that is solid at room temperature as an ink that delays curing, and has an average particle size in the range of 2 to 20μ. A method for producing a melamine embossed decorative board, characterized by using ink containing a filler. 2. The method according to claim 1, characterized in that silicon dioxide is used as the filler having an average particle size in the range of 2 to 20 microns. 3. Claim No. 3, characterized in that in order to make the surface condition of the delayed portion different from that of other portions, unevenness is formed by peeling the resin in the delayed hardening portion between the layers. The method described in paragraphs 1 and 2.