JPS5863446A - Manufacture of melamine decorative board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] This invention relates to a decorative board using aldehyde tree impregnated paper.

Conventionally, a so-called melamine decorative board is known in which a base paper having good permeability is impregnated with a thermosetting melamine/formaldehyde resin, and then laminated onto a base material and cured by heating and pressure. Also known is a technique of printing a pattern on base paper in advance to create a decorative board having a surface-resistant pattern. Furthermore, in order to further enhance the design of this surface, many techniques have been proposed to intentionally create unevenness or differences in gloss. In particular, providing unevenness or differences in gloss that match the pattern can dramatically enhance the design of the surface, and the following methods have been proposed and partially put into practical use.

A typical method is to use a shaping material such as a metal film during hot-pressing to create irregularities or differences in gloss on the surface of the decorative board. However, in this method,
Accurate synchronization between the pattern and the surface condition is generally difficult;
Although it is a simple and stable method, it is difficult to achieve sufficient effects in terms of design. A similar method of forming unevenness on the surface and matching it with the pattern is to apply coloring agent only to the four areas after applying unevenness to the surface during hot press, for example, applying ink to the entire surface. There is a so-called wiping method in which the ink is scraped off from the convex parts after coating, but this method not only has production problems such as low mechanical stability, but also because the ink is exposed on the surface of the four parts. It has a physical property disadvantage in that the surface properties, which are one of the characteristics of melamine decorative boards, are significantly degraded in some areas.

A method for forming surface irregularities without using a forming plate is to use a foaming ink or the like to foam the impregnated paper or during hot press to give only those areas a different surface shape. Proposed. However, with this method, it is not possible to express fine details, and not only is there a problem with the color stability of the recessed portions, but also the foamed portions tend to deteriorate physically. A method has also been proposed in which defects in the physical properties of the surface are improved by removing this area by a method such as polishing after foaming, but this method requires a removal process after pressing, resulting in a decrease in productivity. , price increases are inevitable.

Methods for synchronized embossing include the so-called chemical embossing method, which changes the hardening speed of the resin and takes advantage of the difference in shrinkage, or a method that uses liquid repellent ink to coat the surface with liquid resin and create recesses in that area. Although these methods have been proposed, they hardly produce the unevenness effect under the conditions of hot press, and cannot be said to be effective methods.

The present invention was made in order to eliminate these drawbacks, and relates to the production of a melamine decorative board having a surface roughness and density that matches the pattern using a simple and inexpensive method. The pattern is printed on the base paper, and the melamine
In the production of melamine decorative boards, which are impregnated with formaldehyde resin, dried, then placed on a substrate and hardened and molded by heat and pressure, ink containing a basic substance and normal ink are used as the pattern ink, and low-pressure ink is used as the impregnating resin. A decorative melamine board characterized in that by using a melamine-formaldehyde resin, the glossy state of the part surface corresponding to the pattern formed by the ink containing the basic substance is made different from the glossy state formed by the surface of the mirror plate. The present invention provides a method for manufacturing the same and various methods for making the same more effective.

Printing is performed on base paper with good permeability using normal ink and ink on the acidic side or alkaline side, impregnated with a thermosetting resin promoted by an acid curing agent, and pressurized.
A method of expressing the difference in color by heating is disclosed in Japanese Patent Application Laid-Open No. 54-45576, but as a result of specific studies on this method, the present inventors have found that it is effective in terms of expression effect and stability. The conclusion was that it was still unsatisfactory.

In other words, in the case of acidic ink, there is less change in gloss compared to alkaline ink, and when the pH is adjusted with additives that are liquid at room temperature such as liquid organic amines and mineral acids, and when the pH is adjusted with liquid additives such as liquid organic amines and mineral acids, If highly water-soluble additives such as oxides are used, problems such as bleeding of the pattern at the printing paper stage, blocking, lack of stability of the resin liquid due to elution into the impregnating resin liquid during impregnation, and impregnating resin may occur. Defects such as unevenness due to elution and movement of additives as they move on the base paper during impregnation, and gloss spots due to migration of additives during pressurization and heating occur. We have come to realize that it is necessary to overcome these deficiencies regarding agents and Iiki. As a result of considering these points, in order to produce a melamine decorative board that has a sharp effect and has a difference in surface condition that is stable and in sync with the pattern, based on the principle shown above,
As an additive, it is a stable basic compound that is solid in the range from room temperature to heat processing temperature, has low solubility in water and impregnating resin, and has no deliquescent property that can be easily dispersed in the ink, especially alkaline earth metals. We discovered that hydroxides are effective and that thermoplastic resins, which are highly hydrophobic and melt when heated and pressurized, are most suitable for ink binders (instead of cellulose binders, which are commonly used as ink binders). The invention has been completed.

That is, the gist of the present invention is to apply a pattern to a base paper with good permeability using an ink containing a basic substance as a pattern ink and a normal ink, impregnate with melamine-formaldehyde resin, dry it, and then apply it on the base material. The ink containing the basic substance is placed on the plate and hardened and molded under pressure and heat to make the surface corresponding to the ink containing the basic substance in a different state from the surface formed by the mirror plate, so that the difference in the surface state in sync with the pattern can be observed. In the method for producing a melamine decorative board having a basic substance, a basic substance, particularly a hydroxide of an alkaline earth metal, which is solid in the range from room temperature to 200°C and is substantially insoluble in water, is used as the basic substance, This method of producing a melamine decorative board is characterized in that a highly hydrophobic thermoplastic resin having a softening point lower than the heating temperature during curing and molding is used as a binder for the ink containing a sexual substance.

As a base paper with good permeability, a paper containing titanium of about 80 to 120 g/I is usually used, but there is no particular limitation. Desirably, it is preferable to use so-called neutral paper having a pH of around 7 in view of the life of the impregnated paper when impregnated with melamine resin and the stability of the difference in surface condition during curing. As a normal ink,
Oil-based and water-based materials using cellulose binders that are generally used for printing on impregnated paper may be used, and there are no particular limitations as long as they do not significantly impede resin penetration or adhesion with base paper or other overprinting inks. . A typical base material is a wood-based material such as particle board, but any material that has the properties required for the product and is compatible with the process may also be used (it may also be molded at the same time as the lamination of impregnated paper). Melamine/formaldehyde resin is used as the impregnating resin.

The acid curing agent (including a latent curing agent) may be one commonly used as a curing agent, and of course may contain a penetration aid and other additives as necessary. Melamine/formaldehyde resins include 15-15, which is called low-pressure melamine.
For applications that are molded at a pressure of about 25 kt/cdt,
Typical examples are those called fast-curing types, which are characterized by short-time molding, but there are no particular limitations for the purpose of the present invention, and they can be selected depending on the equipment and conditions.

Basic substances include strong inorganic alkalis such as representative alkali metal hydroxides, monoethanolamine,
Organic amines such as ethylenediamine are unsuitable, as they are thermally and chemically stable within the temperature range from room temperature to molding temperature.
A basic compound that has substantially no deliquescent property or water solubility, and <
K Mg(OH)2, Ba(OH)2, Ca(OH2
Hydroxides of alkaline earth metals such as No. 2 are suitable.

The melamine decorative board produced by the method of the present invention can be produced using a simple method without substantially changing the conventional creation process, and has a surface that stably has a three-dimensional effect that is in sync with the pattern, with almost no increase in price. It is a beautiful decorative board that visually resembles the real thing, especially in the wood grain pattern, and is used in a wide range of applications such as furniture, interior decoration, walls, ceilings, and floors. Examples are shown below.

[Example 1] , 80 g/rrlf) Tan-containing acid-free paper was printed with a wood grain pattern using ink using a normal cellulose binder, and then ink with the following composition 1 was printed on top of it. A base paper for impregnation was created by printing a conduit plate. This is impregnated with an aqueous solution of melamine/formaldehyde resin for ordinary low-pressure melamine decorative laminates containing acid hardeners and penetrants and dried to create impregnated paper containing resin equivalent to 150% of the weight of the base paper. Place it on a particle board with a length of 70 m.
% Glossy mirror plate and cushion material are stacked in order, and the mirror plate temperature is 1.
It was pressed for 4 minutes at 50° C. and a pressure of 20 ky/7, and then cooled.

As a result, a melamine decorative board with a three-dimensional effect was obtained, the surface of which had lost its luster in the conduit portion.

[Example 2] A tile pattern was printed on 80 g/nl titanium-containing neutral paper using an ink using a normal cellulose binder and an ink having composition 2 below, and then a normal fast-curing type melamine decorative board resin was printed on this. Impregnated paper with an aqueous solution of The sheets preheated to 150° C. were stacked together with a cushioning material, pressed for 50 seconds at a mirror plate temperature of 150 to 160° C. and a pressure of 25 kII/cII, and then immediately taken out and cooled.

As a result, a tile-like melamine decorative board with a three-dimensional effect was obtained in which the gloss of the joint parts printed with the ink of Composition 2 disappeared and the other parts were glossy.

[Example 3] 100 g/m" titanium-containing neutral paper was printed with the ink using a normal cellulose binder to print the blurred version and the bone version of the wood grain pattern, and after printing the conduit part with the ink of Composition 3. ,
Ordinary low-pressure melamine laminate lamella, the weight of the formaldehyde resin after drying is 17° relative to the base paper.
Impregnated paper was prepared by impregnating and drying it so that it became %. This impregnated paper is layered on top of a chip sheet that has been mixed with wood chips and a urea resin curing agent and temporarily pressed after mixing, and then a 70' glossy mirror plate and a brush B7 material are layered in order to form a 15'O'C2aky.
/cr/! The sample was pressed for 6 minutes, cooled, and then taken out. As a result, the gloss of the conduit part disappeared and a surface-decorated chipboard with a three-dimensional feel in harmony with the wood grain pattern was obtained. 1 Patent applicant Kazuo Suzuki, Representative of Toppan Printing Co., Ltd.

Claims (4)

[Claims] (1) A pattern is formed on a base paper with good permeability, then impregnated with melamine/formaldehyde resin, dried, and then placed on a base material and hardened and molded by heat pressure when manufacturing a melamine decorative board. In a method in which an ink containing a basic substance in addition to a normal ink is used as the ink, and the condition of the surface of the molded product that is imitated by the ink containing the basic substance is made different from that of other parts, the basic substance is It is solid in the range from to molding heating temperature, water soluble,
A method for producing a melamine decorative board, characterized in that a basic compound having substantially no deliquescent property is used. (2) The method for producing a melamine decorative board according to claim 1, characterized in that an alkaline earth metal hydroxide is used as the basic substance. (3) The melamine according to claim 1, characterized in that a thermoplastic or thermosetting resin that is hydrophobic and has a property of softening below the molding temperature is used as the binder of the ink containing the basic compound. Method of manufacturing decorative board. (4) Production of a melamine decorative board according to claim 3, characterized in that a thermoplastic resin mainly composed of vinyl chloride/vinyl acetate copolymer is used as a binder for the ink containing a basic substance. ’ until method.