JPS5936844B2 - Decorative board manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention involves embossing an overlay sheet material on a base material using a resin embossing mold plate through a layer of a water-based molding resin composition containing an α-olefin maleic anhydride copolymer resin. The present invention relates to a method of manufacturing a decorative board having a remarkable unevenness effect at low cost and with good workability by molding.

Conventionally, it has been known to produce a decorative board with a three-dimensional effect by pasting a printed thin paper onto the surface of a base material with an adhesive, and then pressing or hot-pressing it with an embossed molding plate having irregularities (for example, , Special Publication No. 35139, 1984, Special Publication No. 1977-
10914 etc.).

However, all of these have many drawbacks and require complicated manufacturing methods, making it difficult to put them into practical use. For example, thin paper is bonded to the surface of the base material with adhesive and molded at high pressure and high temperature using a metal embossing molding plate to create irregularities on the base material, so the base material is soft. Plywood is the main material, and embossing is difficult to perform on hard organic materials such as particle board and hardboard, or inorganic boards such as asbestos slate and calcium silicate boards, which have significant irregularities. Furthermore, irregularities on the surface of the base material (cracks in plywood,
Pinholes, etc.) may appear on the surface, so do not use sealant,
It was necessary to perform sufficient sanding, etc. In addition, adhesive is usually used to bond thin paper, but if a filler is used to prevent the adhesive from penetrating into the base material and causing poor adhesion, the moisture in the adhesive It becomes impossible to volatilize the liquid, causing packs and paper cracks, which requires a drying process. In addition, attempts have been made to perform embossing by increasing the amount of adhesive applied to the base material, but current adhesives have a low resin solid content, and if a large amount is applied, the hardening process However, there are disadvantages such as thinning of the eyes, wrinkles, paper cracking, and punctures caused by moisture in the adhesive. Another method is to impregnate the base material and the thin paper with a thermoplastic resin such as polyvinyl alcohol, ethylene vinyl acetate copolymer resin, or a thermosetting resin such as melamine, phenol, benzoguanamine, diallyl phthalate, or alkyd resin. Attempts have also been made to insert paper and apply heat and pressure using an embossing template, but
Thermoplastic resins require the use of cold press after hot pressing, and the performance of the resulting decorative board is poor in heat resistance, chemical resistance, and solvent resistance, and the surface hardness is also low.

On the other hand, the method of emboss molding using thermosetting resin-impregnated paper has limited molding conditions; for example, for melamine resin, the molding temperature is 150°C, the pressure is 801<g/Cd, and the time is 30 minutes, and for diallyl phthalate resin, Molding temperature 135℃
, a pressure of 151<fl/Cl, and a time of 15 minutes, which typically requires high temperature, high pressure, and a long time.
In addition, both require expensive impregnated paper and require an increased number of steps, which are serious disadvantages. As a result of intensive research to eliminate these drawbacks of conventional methods, the present inventors have developed an inexpensive resin by interposing a thick layer of a specific water-based resin for molding between the base material and the overlay sheet material. Embossed templates can be used, and there is no need to seal even if the base material has some unevenness.Furthermore, even on hard base materials, it is possible to use embossed mold plates with a polyurethane feel. We have discovered a method for manufacturing overlay/embossed decorative boards that is economical and has good workability, allowing unevenness differences to be on the order of millimeters (approximately 5 mm), whereas in some cases the unevenness was on the micron order of about 150 μm. Ta.

That is, according to the present invention, a layer made of a water-based resin composition for molding containing a d-olefin maleic anhydride copolymer resin is applied on a base material, an overlay sheet material is stuck on the layer, Next, a resin embossed mold plate with an uneven pattern is placed on top of it, and then heated and pressurized.
The layer made of the water-based resin composition for molding is molded into a cured resin layer having an uneven pattern corresponding to the uneven pattern of the shaping plate, and at the same time, the overlay sheet material is firmly fixed onto the base material through the cured resin layer. characterized by being fixed to
A method for manufacturing a decorative board having a prominent uneven pattern on its surface is provided.

Substrates that can be used in the method of the present invention include any substrate that can be used as a decorative laminate substrate, such as plywood, hardboard, particle board, gypsum board, asbestos slate board, calcium silicate board, wood cement board, and resin board. Although not particularly limited, it has been difficult to provide deep embossing with conventional methods.

A major feature of the present invention is that hardboard, particle board, asbestos slate board, gypsum board, calcium silicate board, etc. can be used. A water-based resin composition containing a d-olefin maleic anhydride copolymer resin that is applied as a thick layer on a base material is an important material for molding polyurethane-like three-dimensional structures that cannot be achieved with conventional adhesives. It is necessary to have good moldability without punctures, thinning, or paper cracking, and also to have adhesive properties. Known molding resin compositions have almost no volatile components and have a resin composition close to 100%. for example,
Thermosetting resins, which have been known for a long time, and thermoplastic resins, whose demand has increased in recent years, are the two main molding resins, but neither of them contains water in their resin compositions. In other words, when talking about thermosetting resins, the main types are area resins, melamine resins, and phenol resins, but these are also called formaldehyde resins, and formalin is one of the main raw materials, and the synthesis reaction is completed. At this point, the water in formalin is mixed with the resin and volatile components (mainly water).
In order to use this as a molding resin, moisture is naturally separated and removed by heating and decompression, followed by cooling, pulverization, and sieving. in this case,
After the synthesis reaction is complete, a large amount of energy is consumed to remove a large amount of water. In addition, since formaldehyde is contained in the removed water and steam, wastewater treatment must meet wastewater quality standards.
Further, the formaldehyde contained in the steam must be incinerated again, which requires a large amount of energy to be consumed again.
As described above, the process is long, consisting of reaction, water removal, crushing, and sieving, and there are difficulties in processing the removed water, resulting in poor productivity. On the other hand, the main types of thermoplastic resins are polyethylene, polypropylene, vinyl chloride, ethylene vinyl acetate, etc., but these resins are in powder or pellet form.
Naturally, it does not contain water.

Therefore, there are no particular problems with productivity, but during the molding process, the resin is heated and melted to a temperature at least 50°C higher than the softening point of the resin to become a liquid, which consumes a large amount of energy and requires cooling. It has the disadvantage that it cannot be burned, and also has the serious disadvantage of being easily combustible. In this way, conventional molding resin compositions are basically molded and cured in a state in which they are heated and melted to give them fluidity, so the essential condition is that they contain no volatile components. there was.

Although these resin compositions have good molding performance,
When an overlay sheet is molded at the same time as in the production of decorative laminates, paper cracking occurs because the overlay sheet is not given plasticity. d- in the present invention
Since the aqueous resin composition containing the olefin maleic anhydride copolymer resin contains an appropriate amount of water, it can impart plasticity to the overlay sheet, is easy to handle, and is inexpensive. The aqueous resin composition containing the α-olefin maleic anhydride copolymer resin has a solid content of 0.1 to 20% as the solid content of the d-olefin maleic anhydride copolymer resin aqueous solution.
20 parts by weight, solid content of vinyl acetate resin emulsion
~60 parts by weight, 2 to 15 parts by weight as solid content of area formaldehyde resin initial condensate, and fillers (wood flour, fiber,
The composition has a water content of 10 to 40% by weight and is formed by mixing 5 to 100 parts by weight of calcium carbonate, etc.).

The above aqueous resin composition used for molding in the present invention has the advantage of having suitable fluidity due to heat of the vinyl acetate resin emulsion, which is a thermoplastic resin, and good crack resistance of the thermoplastic resin, and the properties of the thermosetting resin. In combination with the property of rapidly curing and forming a hard resin layer by heat of the area formaldehyde resin initial condensate, α
- By blending the olefin maleic anhydride copolymer resin, the balanced effect and crosslinking effect of the thermosetting resin and thermoplastic resin are mutually enhanced, resulting in improved durability such as heat resistance, crack resistance, toughness, etc., and moldability. , is highly suitable for the purpose of the present invention. Further, the resin composition has a moisture content of 10 to 4
Because it contains 0%, it can be used as a viscous liquid and has good flow, which is convenient for forming uneven patterns. The advantages of this invention include being able to work at low pressure and low temperature, improving adhesion by improving wetting with the base material and thin paper, and appropriately softening the overlay sheet such as thin paper. brings various benefits to The addition of fillers is aimed at regulating moisture content, lowering costs and improving performance. For example, an inorganic powder may be used to add flame resistance, and an organic powder may be used to add adhesion or impact resistance, depending on the purpose. When carrying out the method of the present invention, first, the aqueous resin composition for molding as described above is coated using a coater such as a bottom coater, reverse coater, roll coater, etc. as shown in FIG. An amount sufficient to finally form an uneven pattern of the desired depth on the upper surface of the base material 1, specifically, about 30 to 4507/Trl in terms of solid content (for comparison, ordinary adhesive The amount of adhesive applied in the manufacture of decorative boards by
An overlay sheet (paper or nonwoven fabric) 3 of approximately 007/Rrl is attached. These overlay sheets may or may not be colored or printed with a pattern (wood grain pattern, abstract pattern, etc.), and may be coated with lacquer, urethane, urethane, etc. on the colored or printed pattern. It may or may not be coated with a paint such as aminoalkyd. This coating is usually applied as a final step after molding is completed. Next, as shown in FIG. A resin embossed forming plate 4 with an uneven pattern is placed in a suspended press 6, and the uneven patterned surface of the forming plate is brought into contact with the surface of the overlay sheet at a temperature of 50 to 120°C and a pressure. 1~15k
g/CTl for 30 to 200 seconds (in FIG. 1, 5 is a cushion rubber sheet).

In this way, as shown in FIG. 2, the cured resin 2' and overlay sheet 3' formed into a pronounced uneven pattern similar to the pronounced uneven pattern of the forming plate are fixed to the upper surface of the base material 1. A board is obtained. The present invention is also characterized in that a resin embossing mold plate can be used because the hot-press molding conditions are extremely low temperature, low pressure, and short time as described above.

Although resin-made embossed mold plates are inferior in physical durability compared to metal ones, they can sufficiently withstand the level of heat and pressure used in the present invention, and are resistant to volatile moisture during hot-press molding. It has the advantages of being indestructible, lightweight, easy to work with, can be reproduced in large quantities, and is inexpensive. Reproductions are easily produced from original natural or artificial models, or from master molds made from them, using paper impregnated with thermosetting resins such as melamine, epoxy, diallyl phthalate, etc. be able to. The molded product having a remarkable uneven pattern obtained in the above manner can be coated with commonly used transparent paints, colored paints such as lacquer, polyester, urethane, alkyd, epoxy, amino resin paints, etc. to improve its surface properties. It is also possible to improve the design effect. Next, the present invention will be specifically explained using examples. All parts and percentages in each example are based on weight. Example 1 Spretsuda was used on lauan plywood with a thickness of 2.7 mm,
1507 is an aqueous resin composition with a non-volatile content of 64%.
A printed thin paper of weight 23R/A coated with brown monochrome gravure printing is layered on a diallyl phthalate resin embossed mold plate with leather pattern unevenness ("Ran" manufactured by Chiyoda Gravure Printing Co., Ltd.). Plate) was inserted into a suspended molded press, and heated at 100°C with a weight of 5 kg/(1-JMo V1
, After being hot-pressed for 30 seconds and taken out from the press, it was found that there was no effect of grain fading due to the conduit of the base plywood, and the surface with fine leather patterns and irregularities in some places was faithfully reproduced. A reproduced embossed surface was obtained.

Next, a urethane resin was applied to this surface using a roll coater and dried to obtain a decorative board having an uneven surface.
Example 2 2011 particle board using Spretzda,
500y of a water-based resin composition with a non-volatile content of 70%
/Cll coating, 80V/A titanium paper with dark reddish brown monochrome printing was pasted on top of it, and on top of that, a diallyl phthalate resin embossing template with a deep uneven Kamakura-bori pattern was attached. Insert the stacked components into a forming press,
Hot and pressure molded under the conditions of 80℃, 5kg/Cd, 200 seconds,
After cooling, a coat of paint was applied, resulting in a decorative board with a deeply engraved Kamakura-bori pattern, which is not seen in conventional embossed decorative boards.

Example 3 A gypsum board with a thickness of 9 ml was coated with 200% of a water-based resin composition with a non-volatile content of 72% using a roll coater.
A wood grain pattern was applied to a 35r/Cd thin paper using gravure printing, and then a pre-coated decorative paper coated with a urethane transparent paint was applied, and a deep uneven pattern that matched the wood grain pattern was created on top of it. Insert the constituent material in which the attached diallyl phthalate resin embossed mold plates are stacked together into a molding press, and press 12.
As a result of hot pressing under the conditions of 0° C., 3 kg/(-JMo V1, 60 seconds), a precoated thin paper embossed decorative gypsum board with noticeable irregularities was obtained.

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view showing the process of the present invention, and FIG. 2 is a sectional view of a decorative board according to the present invention. In the figure, 1 is a base material, 2 is a coating layer of an aqueous resin composition for molding containing α = olefin maleic anhydride copolymer resin, 2' is a layer formed by molding and hardening it, 3 is an overlay sheet, and 4 is a molded and cured overlay sheet, 4 is a resin embossed mold plate, 5 is a cushion rubber sheet, and 6 is a press.

Claims (1)

[Scope of Claims] 1. A layer made of a water-based resin composition for molding containing an α-olefin maleic anhydride copolymer resin is applied on a base material, an overlay sheet material is stuck on the layer, and then A resin embossed mold plate with a concavo-convex pattern is placed thereon, and then heated and pressurized to form a layer made of the water-based resin composition for molding into a concave-convex pattern corresponding to the concave-convex pattern of the mold plate. A method for producing a decorative laminate having a prominent uneven pattern on its surface, which comprises forming a patterned cured resin layer and at the same time firmly fixing the overlay sheet material onto a base material via the cured resin layer. 2. The aqueous resin composition for molding has a solid content of 0.1 to 20 parts by weight in the α-olefin maleic anhydride copolymer resin aqueous solution and 20 to 20 parts in solid content of the vinyl acetate resin emulsion.
The method according to claim 1, which is a composition having a water content of 10 to 40% by weight, comprising 60 parts by weight, 2 to 15 parts by weight as a solid content of a urea formaldehyde resin precondensate, and 50 to 100 parts by weight of a filler. 3 Solid content of water-based resin composition for molding is 30 to 45
2. A method according to claim 1, which is applied as a layer on the substrate in an amount of 0 g/m^2.