JP2753987B2 - Manufacturing method of decorative board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of applying a resin coating agent to the entire surface of a plywood, using a wooden board filled with recesses formed by conduits or the like on the surface, and applying overlaying, painting, etc. thereon. The present invention relates to a method for producing a decorative board comprising:

[0002]

2. Description of the Related Art A plywood is used as a base plate, and a decorative veneer is provided on an upper surface thereof.
In a decorative board manufactured by laminating decorative paper or the like, the surface smoothness and color unevenness greatly affect the commercial value. The color and grain of the surface of the plywood are various depending on the raw wood, and because there are bug holes and cracks on the surface, to prevent uneven color of the surface of the decorative board and to obtain smoothness, after manufacturing the plywood, It has been conventional to apply a repair agent and a filler, and for these, fillers such as abrasive powder, titanium paste, and various repair agents such as latex, epoxy resin, and urethane resin paint are used. ing.

[0003]

Conventionally, recesses to be repaired, such as bug holes, differ depending on the type of material, the size of the hole, the depth, etc. and do not occur at fixed locations. Had a method of applying putty-like objects with a trowel or the like with a lot of manual labor. Such work requires a large amount of labor and time, and it can fill large cracks and bug holes, but cannot fill the recesses due to the conduits scattered all over the plywood. In many cases, the adhesiveness between the adhesive and the top-applied member became poor, and after the production of the decorative board, blisters were generated on the surface, and the commercial value was often lost.

On the other hand, in order to reflect the recent situation of difficulty in recruitment, in order to simplify the above-mentioned manual work, various fillers are blended with the adhesive for decorative application, and the decorative application member and the base plate are combined. A method has been developed to provide both sealing and repair effects at the same time as bonding. However, in such a method, although the labor can be saved, the amount of the filler to be added is limited, so that the sealing and repairing effects cannot be sufficiently exhibited, and the adhesive performance tends to deteriorate. The present invention is intended to solve the above-described problems related to decorative board production, and applying a resin coating agent to the entire surface of the plywood while applying a special method to pressurize the conduit on the surface,
It is an object of the present invention to provide a decorative board having a smooth surface and no color unevenness by using a wooden board obtained by completely filling recesses such as cracks and a method of manufacturing the same.

[0005]

According to the present invention, there is provided a method for producing a decorative board comprising an aqueous latex having a minimum film-forming temperature of 5 ° C. or higher, a polyfunctional aziridine compound having two or more aziridinyl groups in a molecule, and a filler. If necessary, further formaldehyde resin, a resin coating agent comprising a curing agent for the resin,
By applying pressure to the entire surface of the plywood while applying pressure, the wooden board obtained by filling the conduits, grooves, cracks, etc. of the board surface with the coating agent is used as a base plate, and the surface of the wood board is , Overlay, painting and the like.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the above-mentioned copying means that a coating agent is applied to the surface of a plywood, and then the coated surface is pressed with an iron or the like. In order to apply the pressure, for example, a doctor knife made of a thin steel plate usually used for coating is applied at a certain angle so that a few cm of the tip of the doctor knife is almost parallel to the surface of the wood board (plywood) to be coated. It is arranged on a board surface, and the application agent is pressed with a knife, and the applied application agent is pressed against the wooden board surface at the tip end surface of the knife. Usually, a knife coater is used as a coating device.

[0007] As a coating member for applying the profile pressure, a doctor knife made of a thin steel plate having appropriate elasticity as described above is used so that the tip of the knife has an appropriate width and is in contact with the surface of the object to be coated. However, as with the doctor knife, any other flexible member can be used as long as the distal end portion has an appropriate width (length) and can be brought into contact with the surface of the object to be coated. For example, a rubber plate, a plastic plate, or the like can be used.

According to the pressure application according to the present invention, the coating agent is squeezed and applied at the part of the coater which is in line contact with the surface of the object to be coated at a certain angle as in the conventional knife coater. Since the coating agent at the portion of the tip of the coater that is in surface contact is in a pressurized state, the coating agent in the flat portion flows into a concave portion such as a groove on the surface of the workpiece and is filled in a pressurized state. Therefore, it is preferable to select the contact width of the tip portion according to the depth of the concave portion on the surface of the workpiece.

The resin coating composition used in the present invention comprises an aqueous latex having a minimum film-forming temperature of 5 ° C. or higher, a polyfunctional aziridine compound having two or more aziridinyl groups in a molecule, a filler, and, if necessary, formaldehyde. An application agent comprising a base resin and a curing agent for the resin (special curing agent). More specifically, the aqueous latex, a polyfunctional aziridine compound, a formaldehyde-based resin, those comprising a dedicated curing agent and a filler, further include those comprising the aqueous latex, a polyfunctional aziridine compound and a filler, and the like. .

[0010] After the coating agent is applied to the surface of the wooden board, it is dried in a dryer. In the process, when the resin coating agent contains a formaldehyde resin, the thermosetting formaldehyde resin is rapidly cured in the presence of a special curing agent and has a high film forming temperature (5 ° C. or higher). Forms a hard coating. Therefore, it is possible to prevent the coating liquid from excessively penetrating into the wood, to reduce lightening, and to prevent sticking during deposition. When a polyfunctional aziridine compound is contained, curing of the aqueous latex is accelerated by the aziridine compound, and the same effect is obtained. Further, since the coating film after drying is hard and uniform, clogging hardly occurs during surface treatment with a sander, and grinding can be easily performed. As a result, a uniform and smooth base plate surface can be obtained, and in the surface processing such as overlaying and painting, the close contact with the upper processing member is completed, and color unevenness and blistering can be prevented.

Examples of the aqueous latex include emulsions of ethylene vinyl acetate resin, vinyl acetate resin, acrylic resin, acrylic acid-acrylate copolymer resin, acrylic-styrene copolymer resin, acrylic-ethylene-styrene copolymer resin, and the like. There are styrene butadiene latex, carboxylated chloroprene rubber latex and the like, and among them, those having a minimum film-forming temperature of 5 ° C. or more can be used alone or in combination. Latex having a film forming temperature of 5 ° C. or less has a soft coating film upon drying, is difficult to grind during sanding, and reduces workability.

The formaldehyde resin includes urea resin, melamine resin, phenol resin, urea melamine co-condensation resin, resorcinol resin, acetone resin and the like, and one or more of these can be used in combination. As fillers, talc, clay, calcium carbonate, titanium,
Usual fillers such as mica, bentonite, asbestos, wood flour, soy flour, blood flour and corn gluten can be used. Examples of the modifying agent include a viscosity imparting agent such as sodium polyacrylate and cellulose ether; a surfactant such as sodium dodecylbensulfonate; a dispersant such as melaminesulfonic acid and polycarboxylic acid; a water-soluble epoxy compound; There is a coating strength reinforcing agent such as formal and the like, and one or more of these can be used in combination as needed.

As a special curing agent, ammonium chloride,
There are inorganic salts such as ammonium sulfate which react with free formaldehyde in a coating agent to generate an acid, inorganic acids such as hydrochloric acid and sulfuric acid, carboxylic acids such as malic acid and citric acid, and organic sulfonic acids such as paratoluenesulfonic acid. One or more of these can be used in combination. The amount of the dedicated curing agent added is in the range of 0.01 to 0.5, preferably 0.05 to 0.30, by weight based on the formaldehyde resin. When the ratio is less than 0.01, the curing of the coating agent becomes insufficient, which causes a decrease in grinding performance during sticking during the deposition of the base plate and processing of the sander. On the other hand, when the ratio is 0.5 or more, the curing occurs rapidly, so that the pot life of the coating agent is shortened and the coating operation becomes difficult.

A polyfunctional aziridine compound is a compound represented by the general formula

Embedded image (Wherein, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) and have two or more aziridinyl groups represented by Things.

Specific examples of the polyfunctional aziridine compound include trimethylolpropane tris [3- (1-aziridinyl) propionate], trimethylolpropane tris [3- (1-aziridinyl) butyrate], and trimethylolpropane tris [3 -(1- (2-methyl) aziridinyl) propionate], trimethylolpropane tris [3- (1-aziridinyl) -2-methylpropionate], pentaerythritol tris [3- (1
-Aziridinyl) propionate], pentaerythritol tetra [3- (1-aziridinyl) propionate], diphenylmethane-4,4'-bis-N, N'-
Ethylene urea, 1,6-hexamethylene bis-N,
N'-ethyleneurea, 2,4,6- (triethyleneimino) -Syn-triazine, bis [1- (2-ethyl)
Aziridinyl] benzene-1,3-carboxylic acid amide.

The polyfunctional aziridine compound is used as a crosslinking agent for an aqueous latex. The compounding amount is 0.1 to 10 parts by weight based on 100 parts by weight of the aqueous latex. If the amount is less than 0.1 part by weight, the strength of the coating film becomes insufficient, and if it exceeds 10 parts by weight, it is not economical.

The following are used as surface treatment of the base plate: A) For overlay plywood: decorative veneer, resin film, resin impregnated paper, resin veneer, resin-treated veneer, decorative paper, cloth, metal plate, cork , Wood flour, fibers, minerals, asbestos board, etc. B) For painted plywood: nitrocellulose lacquer, amino alkyd resin paint, polyester resin paint, polyurethane resin paint, etc., depending on the application, one or more kinds Can be used in combination. As an adhesive used for bonding with the base plate in the case of overlay plywood, urea formaldehyde resin, formaldehyde resin such as melamine formaldehyde resin, ethylene vinyl acetate resin, vinyl acetate resin, acrylic resin, styrene butadiene copolymer resin and the like There are aqueous latex and the like, and one or more of these can be used in combination. If necessary, such as flour, clay, calcium carbonate, talc, water, etc., are blended with conventional adhesives for plywood production. Fillers and substances that serve as extenders can be added and mixed for use. Further, as a curing agent into the resin composition, inorganic salts such as ammonium chloride,
An inorganic acid such as hydrochloric acid or an organic acid such as malic acid can be added for use.

According to the present invention, as a resin coating agent, a composition obtained by appropriately blending a formaldehyde resin, a polyfunctional aziridine compound, a filler, and a dedicated curing agent with an aqueous latex having a minimum film-forming temperature of 5 ° C. or higher. Used, when applying, against the surface of the plywood, so that a flexible member such as a knife for application hits the surface of the substrate to be coated from the line,
The coating agent filled in the recesses such as grooves and cracks present on the surface of the workpiece is subjected to surface pressure due to the bending of the tip of the flexible member, and is filled in a compressed state to a volume greater than the volume of the recesses. After passing through the flexible member, the coating agent filled in the concave portion of the object drops to the atmospheric pressure and then swells to the volume of the concave portion or more. The expansion allows filling without thinning, and at the same time, filling of a conduit portion that is evident on the plate surface, which could not be achieved by manual operation. Further, in the step of drying the plywood after applying the coating agent, the formaldehyde-based resin in the coating agent causes a rapid cross-linking reaction in the presence of the curing agent, and at the same time, has a high film forming temperature (5 ° C. or higher). Since the aqueous latex forms a strong coating film, it can be easily ground without clogging during sanding. As a result, a base plate having a uniform and smooth surface is obtained, and when performing surface processing such as overlaying or painting on the base plate, problems such as color unevenness and blistering can be solved.

[0019]

【Example】

Embodiment 1 FIG. 50 parts of a urea melamine co-condensation resin having a solid content of 72% (HONEN CORPORATION product UW-096) and an acrylic resin emulsion (Mitsubishi Yuka Birdish product YJ-3031D, minimum film formation temperature 15 ° C, solid content 48)
%) Was previously mixed and stirred. Next, after mixing 0.5 part of carbon black and 20 parts of clay, 5 parts of ammonium chloride is added and mixed uniformly, and 3 parts of trimethylolpropane tris [3- (1-aziridinyl) propionate] is mixed. did. Thereafter, the mixture was supplied from the mixing tank to the traverser by a snake pump, and was uniformly discharged from the traverser onto the line as a resin coating material for repair and filling. The discharged liquid was uniformly applied to the surface of the plywood by a knife coater having a knife angle of 20 ° and a contact width of 15 mm with respect to the plate surface of the tip of the knife, and then dried and deposited at 90 ° C. The plywood that had been left standing for 24 hours was subjected to sanding treatment to form a base plate.

Embodiment 2 FIG. Styrene / acrylic copolymer resin emulsion (Hoechst synthetic product Movinyl 868,
100 parts of the minimum film forming temperature of 20 ° C. and the solid content of 50%) were previously stirred. Next, 0.15 parts of carbon black, 0.15 parts of bengara, 30 parts of calcium carbonate, 10 parts of wood flour
And 3 parts of water, then uniformly mixed, 6 parts of pentaerythritol tris [3- (1-aziridinyl) propionate] was added, and the mixture was thoroughly mixed. Then, the coating solution was treated in the same manner as in Example 1. Was applied to the surface of the plywood, dried and deposited, followed by sanding to obtain a base plate.

Embodiment 3 FIG. 100 parts of styrene / acrylic acid alkyl ester copolymer emulsion (Mitsubishi Yuka Bird dish product YJ-1595D, minimum film formation temperature 20 ° C, solid content 53%) in 1 part of silicone foam stabilizer (Nihon Unicar product L-5421) 1 Was added and mixed and stirred in advance. Next, after mixing 0.5 parts of Bengala, 10 parts of wood flour, and 5 parts of talc, 10 parts of paratoluenesulfonic acid was added and uniformly mixed.
6 parts of 4'-bis-N, N'-ethyleneurea are added,
After sufficient mixing, this coating solution was applied to the surface of the plywood in the same manner as described in Example 1, dried and deposited, and then sanded to obtain a base plate.

Embodiment 4 FIG. Melamine resin with a solid content of 60% (Hounen Corporation product MW-085) 80
Parts, vinyl acetate / ethylene / vinyl chloride copolymer resin emulsion (Hoechst synthetic product Movinyl 191E, minimum film forming temperature 30 ° C, solid content 50%) 20 parts and viscosity imparting agent (Sannobuco SN thickener 803) 2 parts Stirred. Next, carbon black 0.
After mixing 5 parts, 30 parts of titanium oxide and 20 parts of clay,
10 parts of ammonium sulfide was added and mixed uniformly to obtain bis [1- (2-ethyl) aziridinyl] benzene-1,
After adding 4 parts of 3-carboxylic acid amide and mixing well, the obtained coating solution was applied to the surface of plywood in the same manner as described in Example 1, dried and deposited, and then sanded to finish the base plate. Obtained.

Embodiment 5 FIG. Plate in the same manner as in Example 4 except that pentaerythritol tris [3- (1-aziridinyl) propionate] was used instead of bis [1- (2-ethyl) aziridinyl] benzene-1,3-carboxyamide. Was repaired and sealed.

Comparative Example Vinyl acetate resin (Polysol PS-
(3HA minimum film formation temperature 3 ° C.) 100 parts, diethylene glycol 5 parts, clay 30 parts, talc 5 parts and water 5 parts are mixed and stirred. Further, 0.15 part of carbon black and 0.15 part of bengara were mixed. This mixture was applied to the surface of the plywood, dried and deposited in the same manner as in Example 1, and then sanded.

Embodiment 6 FIG. A 2.5 mm thick 3-plyerone plywood prepared by the methods of Examples 1 to 5 and Comparative Example was used as a base plate, and a veneer of teak, dao, walnut, and rosewood was adhered thereon as a decorative sticking member, and its performance test was performed. Was performed. (1) Work conditions Base plate 2.5 mm thick, 3-ply Rawan plywood Veneer veneer 0.2 mm thick teak, dao, walnut, rosewood Adhesive compounding (* 1) Melamine resin 30 parts (* 2) Styrene butadiene latex 10 Part Flour 10 parts Malic acid 0.2 part Note: * 1 (ML-045, Honen Corporation) * 2 (JSR-0692, Japan Synthetic Rubber Co., Ltd.) Coating amount 10g / 900cm ² Open assembly time 5 minutes Closed assembly time 10 minutes Heat pressure condition 110 ℃ 8Kg / cm ² 60 seconds

(2) Test method (according to Japanese Agriculture and Forestry Standards for special plywood) (a) Type 2 immersion peel test After immersing the test piece in hot water of 70 ± 3 ° C for 2 hours,
Dry at ± 3 ° C for 3 hours. (B) Cold repeated test After fixing each of two test pieces of 15 cm square with a metal frame, the test pieces were left in a thermostat at 80 ± 3 ° C for 2 hours, and further −
The process of leaving in a thermostat at 20 ± 3 ° C. for 2 hours is repeated twice, and left to reach room temperature.

[0027] ：: no dry cracking observed △: slight dry cracking observed ×: considerable dry cracking observed

[0028] ：: Almost no dry cracking △: A small dry crack was slightly observed ×: A large dry crack was observed throughout

Example 7 2.5 mm prepared according to the methods of Examples 1 to 5 and Comparative Example.
A 3 ply thick plywood plate was used as a base plate, and a precoated paper was adhered thereon as a decorative sticking member, and the adhesion performance was compared. (1) Working conditions Base plate 2.5 mm thick, 3-ply Rawan plywood Decorative paper 23 g / m ² Pre-coated paper adhesive compounded (* 1) Melamine resin 30 parts (* 2) Styrene butadiene latex 10 parts Rice flour 15 parts Water 5 parts 0.2 parts of p-toluenesulfonic acid * 1 (HONEN CORPORATION product ML-04)
5) * 2 (Nippon Synthetic Rubber Co., Ltd. product JSR-0668) Coating amount 5.5 g / 900 cm ² Pre-drying 100-105 ° C 10 seconds Line speed 50 m / min Heat roll press 3 Surface temperature 30 ° C, 75 ° C, 65 ° C

(2) Test method (according to the Japanese Agricultural and Forestry Standards for special plywood) (a) Plane tensile test A test piece is bonded to a metal plate using a cyanoacrylate-based adhesive, and the cut has a depth reaching the base plate around the test piece. After attaching
Perform a plane tensile test. (B) Class 2 immersion peel test Same as the method described in Example 6.

[0031] Note: The numerical value above the plane tension column indicates the average value (Kgf / 25mm) of 20 pieces, and the numerical value in () indicates the paper or plywood member breaking rate (%).

Claims (2)

(57) [Claims] 1. A resin coating agent comprising an aqueous latex having a minimum film-forming temperature of 5 ° C. or higher, a polyfunctional aziridine compound having two or more aziridinyl groups in a molecule, and a filler is coated on the entire surface of the plywood. By using a wooden board obtained by filling recesses such as conduits, grooves, and cracks of the board surface with the coating agent as a base plate by applying pressure while performing processing such as overlaying and painting on the surface of the wood board. A method of manufacturing a decorative board, characterized by applying a method. 2. A resin coating comprising an aqueous latex having a minimum film forming temperature of 5 ° C. or higher, a polyfunctional aziridine compound having two or more aziridinyl groups in a molecule, a formaldehyde resin, a curing agent for the resin, and a filler. By applying an agent to the entire surface of the plywood and applying a pressure, a wooden board obtained by filling a concave portion such as a conduit, a groove, or a crack of the board surface with the coating agent is used as a base plate. A method for producing a decorative board, characterized in that the surface is subjected to processing such as overlaying and painting.