JPS58110250A - Manufacture of same-state embossed 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 The present invention relates to a method for manufacturing a thermosetting resin decorative board having an uneven pattern that matches the pattern and having good surface properties such as wear resistance.

Thermosetting resin decorative boards such as melamine decorative boards generally have a pattern on a base material (usually a laminate of kraft paper itself impregnated with a thermosetting resin, called a core sheet). The printed decorative base paper (pattern sheet) and an overlay sheet to prevent the printed pattern on the decorative base paper from being worn away are impregnated with a thermosetting resin liquid, pre-dried, and then laminated, and the laminated body is placed on a pair of hot plates. It can be obtained by sandwiching the mixture in between and heating and pressurizing it.

However, in the thermosetting resin decorative board manufactured in this way, the presence of an overlay sheet used to protect the printed pattern clouds the printed pattern and makes the appearance unclear, so it is difficult to improve the decorative effect. is not a good thing. In order to eliminate these drawbacks of the conventional method, instead of the overlay sheet, a resin layer containing abrasion-resistant mineral fine particles is formed on the printed pattern layer of the decorative base paper to improve the abrasion resistance of the decorative board. A method has also been proposed (Japanese Unexamined Patent Publication No. 53-9
However, although the presence of the mineral fine particle-containing layer in this method is improved compared to the overlay sheet, it is true that it visually contributes as a shielding layer. Therefore, it can be said that the effect of improving visual clarity is limited only by reducing the shielding effect. In addition, the decorative board obtained by this method has a decorative effect only by the printed pattern, similar to the decorative board obtained by the above-mentioned overlay sheet, so the decorative effect must be 141 tones on a flat board. .

On the other hand, many methods have been proposed for producing thermosetting resin decorative boards that have three-dimensional decorative effects.

A typical example is a method in which suppression is performed using a roller or template with an uneven surface. However, with these methods, it is extremely difficult to obtain an uneven pattern that is in sync with the printed pattern applied to the surface of the decorative board.

On the other hand, the printed version has an uneven pattern that is in sync with the printed pattern.
Known methods for obtaining plates include a method using a thick layer of printing ink, and a method using resin fill in the printed and non-printed areas. However, although these methods provide an uneven pattern that is in sync with the printed pattern in principle, it is inevitable that the unevenness will be reduced in the final heating and press forming process between hot plates, resulting in sufficient three-dimensionality. It is hard to say that it has any effect. In order to eliminate such drawbacks, the research group to which the present inventor belongs has already developed a method for manufacturing a decorative board with symmetrical embossed projections (Japanese Unexamined Patent Application Publication No. 1983-1992).
-111554). In this method, a normal printing layer with a desired pattern is formed on decorative base paper using normal printing ink, a foamed printing layer with a desired pattern is formed using heat-foaming printing ink, and then a foamed printing layer with a desired pattern is formed using a heat-foaming printing ink. The decorative base paper on which the printing layer has been formed is impregnated with a thermosetting resin and dried to form an impregnated paper, and this impregnated paper is combined with a base material, and then heated and pressure molded. .

However, this method also has some drawbacks. The biggest problem is that it is difficult to obtain a synchronized embossed pattern with a desired degree of three-dimensionality while maintaining the surface properties of the product.

That is, when this method is applied to decorative laminate 14 having a normal overlay sheet, the heat-foamable printing layer is placed under the overlay sheet, and when heated and pressure-molded between a pair of heating plates, the heat-foamable printing layer The ink printed portion permeates the fibers of the overlay sheet and foams while curing together with the impregnating thermosetting resin layer in that portion. Since the heated and foamed portion of the foamable ink is weakened compared to other portions, it adheres to one of the pair of heating plates when the pair is opened and is selectively removed.

However, in reality, due to the presence of the overlay sheet, the removal of the heated foam section is not as selective;
Rather than sufficient recesses, only a matte-like matte portion is formed. Furthermore, since the heated and foamed ink is required to float through the overlay sheet, it is inevitable that the printed pattern will be slightly blurred.

Although the above-mentioned drawbacks are alleviated when no overlay sheet is used, in this case, the surface properties of the finished decorative laminate are of course significantly degraded.

The present invention solves the above-mentioned problems with the conventional method for manufacturing thermosetting resin decorative laminates, and produces thermosetting resin decorative laminates that have an uneven pattern that matches the printed pattern while maintaining desired surface properties. The purpose is to

According to the research of the present inventor, the above-mentioned object is achieved by using the above-mentioned JP-A-53-9 in place of the overlay sheet when applying the method described in the above-mentioned JP-A-54-111554.
It has been found that this can be achieved by forming a resin layer containing wear-resistant mineral fine particles as described in Japanese Patent No. 2875 and the like. That is, the method for producing a tone embossed decorative board of the present invention involves forming a normal printing layer of a desired pattern on a decorative base paper.

A decorative sheet formed by sequentially forming a heat-foamable printed layer with a desired pattern and a resin layer containing wear-resistant mineral fine particles is impregnated with a thermosetting resin liquid and further dried, and the resulting impregnated decorative sheet is used as a base. It is characterized in that it is laminated on a material, and the laminated body is sandwiched between a pair of hot plates and molded under heat and pressure.

The reason why a thermosetting resin decorative board with harmonious appearance and surface properties can be obtained by the method of the present invention is considered to be as follows.

(a) Unlike the case where an overlay sheet is used, the mineral fine particle-containing resin layer is removed from the four parts of the decorative board obtained by the present invention, so deterioration of the surface properties in that part is unavoidable. However, in thermosetting resin decorative boards, such partial loss of the surface protective layer often causes almost no problem. For example, the most attractive pattern to add to a thermosetting resin decorative board is a wood grain pattern, and it is often desirable to form recesses that match the conduit pattern, especially as is the case with natural tree roots. . In this case, since the conductive/α pattern is in the form of fine lines, the loss of the protective layer in that area will almost always lead to a decrease in surface properties, especially wear resistance, which is usually the most required physical property. There is no.

(b) Since the four-part pattern does not have a resin layer containing fine mineral particles, the depth of the four-part pattern increases.

(Compared with a simple resin film, the resin layer containing mineral fine particles can selectively remove the pattern part easily, and a four-part pattern with sharp edges can be obtained.

(b) Visually, the mineral fine particle-containing resin layer serving as a shielding layer is selectively removed in the patterned area, albeit slightly.

Hereinafter, the method for manufacturing a thermosetting resin decorative board of the present invention will be explained in more detail with reference to the drawings. In the following description, 1
%" and "parts" are based on weight unless otherwise specified.

As shown in FIG. 1, the decorative base paper 1 used in the present invention includes:
Generally, a printing layer 2 made of a normal printing ink is provided by a normal printing method such as gravure printing, gravure offset printing, silk screen printing, flexo printing, etc., and furthermore, according to the present invention, a printing layer 2 made of a heat-foamable printing ink is applied. A foamable printed layer 3 is provided. As the heat-foamable ink, for example, 10 parts per 100 parts of binder resin.
A product obtained by adding ~50 parts of a blowing agent and mixing and kneading with a solvent is used. As the foaming agent, foamed capsules such as microspheres manufactured by Dow Chemical Company or microtools manufactured by Matsuhemoto Yushi Pharmaceutical Co., Ltd. (both are vinylidene chloride-acrylonitrile copolymer microcapsules containing neopentane and others); azodicarbonate; Organic blowing agents that generate N2 or ao2 by thermal decomposition such as amide, azobisisobutyronitrile, dinitropentamethylenetetramine, paratoluenesulfonylhydrazide, and 4,4-oxybenzenesulfonylhydrazide; and stopper, ammonium carbonate, etc. Inorganic foaming agents and the like are used. In addition, the binder resins constituting the foamable ink include ethyl cellulose, ethyl hydroxyethyl cellulose, cellulose acetate phlohione),
Cellulose derivatives such as nitrocellulose and cellulose acetate, styrene resins and styrene copolymer resins such as polystyrene and polyα-methylstyrene, polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate,
Acrylic or methacrylic resin alone or copolymer resin such as polybutyl acrylate, rosin, rosin-modified maleic acid resin, rosin-modified phenol resin, rosin ester resin such as polymerized rosin, polyvinyl acetate resin, coumaron resin, vinyl toluene m Among resins, vinyl chloride resins, polyester resins, polyurethane resins, butyral resins, polyamide resins, vinyl chloride-vinyl acetate copolymer resins, etc., it is preferable that the softening temperature of the binder resin and the decomposition or foaming temperature of the blowing agent are close to each other. And, for the binder resin,
One or more binder resins are selected and used, which will be described later and have low permeability to the paint constituting the resin layer containing wear-resistant mineral fine particles.

In addition to the vehicles mentioned above, foaming inks also contain dyes and
Pigment colorants, plasticizers, stabilizers, surfactants, drying agents,
Auxiliary desiccants, curing agents, emulsifiers, thickeners, fillers, dispersants, solvents, and diluents can be appropriately added and kneaded.

Furthermore, it is preferable to add a liquid repellent agent to prevent penetration of the thermosetting resin liquid from the viewpoint of forming the recesses, and it is preferable to add silicone oil, wax, grease, etc.

The heat-foamable printed layer 3 is formed by, for example, gravure printing, gravure offset printing, silk screen printing, flexographic printing, intaglio printing, etc. so as to match the pattern of the normal printed layer 2. The amount of coating (on a dry basis; the same applies to other layers below) varies depending on the pattern to be formed, but for example, when forming a conduit pattern, 1 to 1
Approximately 11'IAn'' is appropriate.

Next, as shown in FIG. 2, a layer 4 containing wear-resistant mineral particles is formed to obtain a cosmetic sheet A).

As the wear-resistant mineral fine particles, alumina, silica, silicon carbide, zirconium oxide, cerium oxide, etc. having a particle size of 10 to 50 mm are preferably used, and alumina is particularly preferred because of its hardness and economic efficiency.

The mineral fine particle-containing resin layer 4 contains 10 of such mineral particles.
0 parts to 25 to 25 parts of a binder resin such as microcrystalline cellulose, acrylic resin, carboxymethyl cellulose, methyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, etc.
It is obtained by mixing and kneading 50 parts of the coating material with water and a solvent or dispersion medium, applying the coating by gravure coating, roll coating, air knife coating, etc., and drying. If necessary, a bond promoter such as a silane coupling agent may be added to the ink to improve the bond between the mineral fine particles and the thermosetting resin. The coating amount is 5 to 1054/m", especially 3.5 to 5.0 ψ/m"
A male grade is preferable. If the amount applied is too small, the effect of improving surface properties such as wear resistance will be poor, and if it is excessive, formation of recesses will be inhibited.

The thus obtained decorative sheet A is impregnated with a resin liquid containing a thermosetting resin such as melamine-formaldehyde resin, diallyl phthalate resin, unsaturated polyester resin, benzoguanamine resin, epoxy resin, etc. using a normal impregnation device, By heating and drying at a temperature below the curing temperature, an impregnated decorative sheet B as shown in FIG. 3 is obtained.

Next, the thus obtained impregnated decorative sheet B is layered on a base material such as core paper, hot tickle board, plywood, etc., and heated by being sandwiched between a pair of heating plates (bell plates) 7a and 7b. Apply pressure. Thereafter, when the hot plates 7a and 7b are opened, as shown in FIG. 5, the mineral fine particle-containing resin layer 4 and the thermosetting resin layer 5 are almost integrated, and the foamed printing@3 that has been foamed by heating becomes brittle.

In addition, the thermosetting resin in the surrounding area is pushed away and becomes brittle, and this area adheres to the mineral fine particle-containing resin layer 4 and the hot plate 7a and is removed, so that a slight recess 3a is formed.

In the manner described above, a thermosetting resin decorative board having a synchronized embossed profile according to the present invention is obtained. However, if the coating amount of the foamed printing layer on the impregnated decorative sheet is small, the adhesion and removal of the resin in the foamed printing section 3 will be insufficient, and the concave portions will not be formed uniformly, resulting in a matte state. Sometimes it stops. In such a case, it is preferable to further perform solvent coating and polishing as post-processes. That is, on the surface of the decorative board obtained as shown in FIG.
When microcapsules are used as the binder resin and foaming agent constituting the foamable resin layer 3, such as ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate and butyl acetate, and aromatic solvents such as toluene. A roll coater is used to apply a solvent that has the effect of dissolving the capsule wall.
When applied with a flow tool or the like, the remaining foamable printed layer 3b swells (Fig. 6), and the surface is then polished with a flow roller or the like to further selectively remove the parts weakened by the swelling. As a result, it becomes possible to form a clearer concave portion 3C (Fig. 7).

Thereafter, post-treatments such as heating or radiation irradiation treatment for drying or curing are performed as necessary.

As described above, according to the method for producing a tuned embossed decorative board of the present invention, a thermosetting resin decorative board having both excellent surface physical properties and a tuned double embossed pattern giving an excellent three-dimensional effect can be obtained.
In particular, production 1 of a wood-grain-like thermosetting resin decorative board with concave conduit pattern portions is optimal.

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

Example 1 A wood grain pattern was gravure printed on the surface of a colored base paper for decorative boards with a square meter basis of 80 ψ/- using a conventional gravure ink having the following formulation.

Using conventional gravure ink, a conduit portion that completely matched the wood grain pattern obtained in Section L was gravure printed using a heat-foamable ink having the following composition.

Heat-foamable ink■ (Dawukee Cuff, manufactured by Co., Ltd., Air) A resin solution containing alumina fine particles of the following composition was applied to the decorative paper obtained as above for 3.5S using an air knife coating method.
It was applied in a coating amount of L/m (dry) and dried at a temperature of 100°C to obtain a decorative sheet.

Resin liquid water containing alumina fine particles 890
Thialumina (average particle size 30μ) 7% Microcrystalline cellulose 1.8chi (manufactured by Hakusui Unicar Co., Ltd., A-
1100) Carboxymethylcellulose 0.8% Next, this decorative sheet is impregnated with a thermosetting resin 115 liquid consisting of 50 parts of melamine formaldehyde resin, 45 parts of water, and 5 parts of isopropyl alcohol, and a conventional diallyl phthalate resin or melamine resin. The sheet was impregnated with melamine resin at a ratio of 90 P/ln' (dry) using a commercially available impregnating device, and dried to obtain an impregnated decorative sheet.

This impregnated decorative sheet was laminated on four sheets of core paper, the laminated body was sandwiched between two mirrored plates, and the pressure was set to 100 using a heat press.
When heat and pressure molding was carried out under the conditions of Shun/1yxj, 135°Cl2O, the conduit pattern matched the wood grain pattern normally printed, and was matte compared to the surrounding area, resulting in a 3D shape with some recesses. We were able to obtain a high-pressure melamine decorative board with matching embossing.

Furthermore, approximately 10% of N[ethyl acid] was applied to the entire surface of the obtained decorative board.
When it was applied at a ratio of 7/- and polished with a puff roller, the concave portions of the four pipe portions became deeper and a decorative board with a more three-dimensional effect was obtained.

The surface abrasion resistance of the decorative board thus obtained was determined by JI
Evaluation was made by S thermosetting resin decorative board abrasion test. The evaluation results are shown in the table below along with the evaluation results for the high-pressure melamine decorative board produced using the overlay sheet by a conventional method.

As mentioned above, the melamine decorative board according to the present invention not only has a wood grain-like embossed pattern with an excellent three-dimensional effect, but also has better wear resistance than the high-pressure melamine decorative board with an overlay sheet, which only has a general planar pattern. It can be seen that it has

Example 2 After obtaining a decorative sheet in the same manner as in Example 1, a quick-drying melamine resin (manufactured by Yasan Kagaku Kogyo Co., Ltd.) was applied to this decorative sheet.
A resin solution prepared using Santotsubu M-7r)O) was impregnated at a dry impregnation rate of 1iID8ψ/m'' and dried to obtain an impregnated decorative sheet.

This impregnated decorative sheet was stacked on a particle board having a thickness of 151 B, and heat-press molding was performed under the conditions of a pressure of 20 l/cd and 150'0.3 min. As a result, the conduit pattern part is
A low-pressure melamine decorative board with synchronized embossment that was in sync with the normal printing layer, was matte than the surrounding area, and had a three-dimensional effect with unevenness was obtained.

Example 3 A decorative sheet impregnated with the same alumina fine particle-containing resin liquid as in Example 1 was produced. However, as a foaming agent, Micropearl RQ-507 manufactured by Matsumoto Yushi Seiyaku Co., Ltd. was used instead of Microspheres manufactured by Dow Chemical Company. The obtained decorative sheet was impregnated with a thermosetting resin liquid of the following composition during drying for 120y.
-/- and dried in a hot air dryer having drying zones ranging from 6D''C to 100C to produce an impregnated decorative sheet.

Thermosetting resin liquid diallyl phthalate prepolymer 100 parts Benzoyl peroxide 3 parts Internal mold release agent
0.5 parts Polymerization inhibitor (hydroquinone)
0.01 part methylated silica (diameter 16 μm)
3 parts This impregnated decorative sheet was layered on a particle board with a thickness of 15 IIls, and using a duralumin board with a mirror finish, a pressure of 20 K9/am? , 130°C1
Heat and pressure molding was carried out under conditions of 15 minutes to obtain a tuned embossed diallyl phthalate decorative board in which the conduit pattern portion was somewhat matte than the surrounding area and slightly recessed.

Further, 10 f/- of ethyl acetate was applied to the above decorative board using a roll coater, and the surface was polished with a puff roller to obtain a decorative board with a three-dimensional effect in which the conduit pattern was further recessed.

[Brief explanation of the drawing]

1 to 7 are schematic cross-sectional views in the thickness direction of the decorative board to show each step of the manufacturing method of the tuned embossed decorative board of the present invention. The figure shows after formation of a resin layer containing fine mineral particles, Figure 3 shows after the thermosetting resin has been melted, Figure 4 shows the heat-pressing molding process, Figure 5 shows after heat-pressing molding, and Figure 6 shows after swelling by solvent coating. , and FIG. 7 respectively show the state after polishing. 1... Decorative base paper 2... Normal printing layer 3... Heat foamable printing @ (5a: after heating and pressure molding, 3b = solvent Swelling state after coating, 3C: after polishing) 4...Resin layer containing fine mineral particles 5...
...Thermosetting resin 6 ... Base material 7a, 7b ... Heat plate A ... Decorative sheet B ... Impregnated decorative sheet Fang 1 Fig. 8 Fig. Fang δ Fig. 7 Fig. Fig. 2 Fig. Fig. 4 Fig. Fig. 6

Claims (1)

[Scope of Claims] 1. A decorative sheet formed by sequentially forming on a decorative base paper an illll side layer with a desired pattern, a heat-foamable printed layer with a desired pattern, and a resin layer containing wear-resistant mineral fine particles, A synchronized sheet is impregnated with a thermosetting resin liquid and further dried, the obtained impregnated decorative sheet is laminated on a base material, and the laminated body is sandwiched between a pair of hot plates and molded under heat and pressure. Manufacturing method of embossed decorative board. 2. The method according to item 1 above, further comprising the step of applying a solvent to the surface of the obtained decorative board and then polishing it. 3. The above-mentioned No. 1 in which the pattern of the foam printing layer is a wood conduit pattern.
term or @2 term method. 4. The method according to any one of items 1 to 3 above, wherein the wear-resistant mineral fine particles are alumina with a particle size of 10 to 50 μm.