JPS5832622B2 - Method for manufacturing decorative board with foam coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a decorative material having a foamed coating film by directly providing an unfoamed foamed coating layer on the surface of a base material such as plywood, hard fiberboard, particle board, wood wool cement board, etc., and heating the layer. This invention relates to a method for manufacturing a board.

2. Description of the Related Art Conventionally, decorative boards used for floor finishing materials, mural materials, etc. have been coated with a foamed resin coating on the surface of a substrate.

This decorative board is usually manufactured by adhering a foamed sheet material that has been formed into a sheet in advance to the surface of a substrate.

When this method is used, the process of attaching the foam sheet material to the surface of the base material is complicated and it is difficult to firmly adhere the foam sheet material to the surface of the base material.Also, since a continuous sheet is cut and attached, each decorative board has to be attached separately. There are drawbacks such as different surface patterns.

Therefore, in order to form a foamed coating film on the surface of a base material, it would be possible to heat and foam the unfoamed paint applied to the surface of the base material and mold it appropriately to manufacture a decorative board. is in good shape.

However, according to this method, the surface layer of the coating film can be easily heated and foamed, but the lower layer of the coating film is blocked from heat by the surface layer and the thick base material, leaving the unfoamed and uncured 1-
! : The adhesion between the foam molding layer and the base material is insufficient, and the heat insulation and elasticity of the foam molding layer do not reach the desired values.

Therefore, it is possible to preheat the base material to 80 to 120°C in order to heat it from the base material side in the same way as when applying foamed resin to the sheet, but heating thick substrates such as plywood or hard fiberboard can be considered. This is due to the loss of thermal energy, which causes uneven moisture content of the substrate or partial carbonization, which not only makes it impossible to obtain a uniformly foamed film, but also causes warping of the substrate. It is not possible to carry out stable industrial production.

Specifically, the present invention provides a method for manufacturing a decorative board that can form a uniform foamed hardened layer without causing any problems with the surface of the foamed resin layer as well as the base material. With the goal.

That is, the method for manufacturing a decorative board according to the present invention does not require the coating film formed on the surface of the base material to be formed using a single type of foamed resin material, but rather the coating film is formed from several types of foamed resin materials having different foaming temperatures. However, by forming the resin material from the lower layer to the upper layer, the foaming temperature is increased according to the temperature gradient during heat treatment.
When this coating film is heated, uniform foaming can occur over the entire shield.

According to this method, the lower layer of the coating is made of foamed resin with a relatively low foaming and softening temperature, and the foaming and softening temperature is gradually increased toward the upper layer, so the coating is kept at a constant temperature. Even if a temperature gradient occurs in the coating film when heated for a certain period of time, the coating film can be foamed evenly over the entire layer, and the lower layer will foam and harden in the same way as the upper layer without overheating the surface layer. A decorative board having a decorative layer can be manufactured.

Since the base material is not preheated when manufacturing this decorative board, thermal energy is not consumed and there is no concern that the base material will warp.

This will be explained in more detail as follows.

As the substrate 1 of the decorative board, an appropriate material such as plywood, hard fiberboard, particle board, wood wool cement board, etc. is used.

Then, a plate with an appropriate thickness is selected depending on the intended use of the product. For example, if this product is to be used as a flooring material, a thick plate is selected as the base material.

A multilayer coating film 2 made of foamed resin paint is formed on the surface of this substrate.

However, when forming this coating film, each layer 2a, 2b, 2c is formed from a foamed resin with a different foaming and softening temperature, and moreover, the foaming and softening temperature is raised stepwise from the lower layer 2a to the upper layer 2c. Let it form.

The coating resin used to form this coating film is a thermoplastic synthetic resin such as vinyl chloride, vinyl acetate emulsion, thermoplastic urethane, or soft vinyl chloride paste, and the blowing agent mixed in the resin is azodicarbonamide. , dinitrosopentamethylenetetramine, organic blowing agents such as benzenesulfonylhydrazide, bicarbonate)
Inorganic foaming agents such as IJum and ammonium carbonate are used.

When preparing a paint mixture of resins and foaming agents selected from these, resins and foaming agents with well-balanced softening and foaming temperatures are mixed to obtain foamed paints that soften and foam at different temperatures. Or, 0BP (dibutyl phthalate),
Adjust the degree of softening by increasing or decreasing the amount of plasticizers such as DOP (di-2-ethylhexyl phthalate), or adjust the degree of foaming by adding decomposition retardants such as fumaric acid, phthaloyl chloride, and hydroxynone. Prepare several types of paints with different foaming and softening temperatures by adjusting them.

Several types of paints prepared in advance are sequentially applied onto the substrate 1 using paint equipment such as a flow coater, knife coater, or roll coater, starting from the one with the lowest foaming softening temperature.
Forms a thick coating of 2 coats or more.

Prior to forming this coating film, it is preferable to form a waterproof layer on the surface of the substrate 1 in advance by applying a sheen.

By forming this waterproof layer, it is possible to prevent moisture that evaporates from the substrate when the coating film is heated from being mixed into the foaming agent or the paint and inhibiting its foaming and curing.

When the rolled decorative board is used for something that is easily exposed to moisture, such as flooring, it should be coated with sheen on the back side or coated with moisture-proof or waterproof paper to prevent it from stretching or warping due to moisture absorption. It is a good idea to paste it.

When the coating film thus formed on the substrate is heat-treated in an infrared drying oven or hot air drying oven, the upper layer of the coating film is at a high temperature and the lower layer is at a low temperature. If the film is set in advance to foam and soften at a temperature corresponding to the temperature rise slope, uniform foaming can be achieved over the entire layer of the coating film even if there is a difference in temperature rise.

For example, the thickness is 14 mm, the specific gravity is 0.9, and the length is 180 cm.

A waterproof layer was formed by coating 5 layers of acrylic urethane based sheen on the surface of a 30 cm wide fiberboard and drying it to form a waterproof layer.A plate-like body with polyethylene waterproof paper welded to the back was used as a substrate and the following was applied to the surface. A three-layer coating film was formed using the following paint.

Vinyl chloride paste resin is used as a paint for the lower layer without residue.
... 100 parts ffi agent N) Bp-dibutyl phthalate) ... 80 parts Stabilizer ......
・・・・・・・・・・・・Two parts blowing agent (
AZDN-azobisisobutyronitrile, decomposition temperature 90
~115℃)......3 parts of unfoamed synthetic resin were applied to a thickness of 0.1 using a flow coater, and then vinyl chloride paste resin was applied as the middle layer paint...・・・・・・・・・
...100 parts plasticizer (DBP)...
・・・50 parts stabilizer・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・2 parts blowing agent (0BSH=4.4'
-Oxybisbenzene sulfonylhydrazide, decomposition temperature 120-140°C)
......3 parts of unfoamed synthetic resin are applied to a thickness of 0.1 mm using a flow coater, and finally, vinyl chloride paste resin is applied as the surface coating material...・・・
・・ios plasticizer (DBP)・・・・・・・・・
・・30 parts stabilizer・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・Two parts blowing agent (DPT-dinitrosopentamethylenetetramine, decomposition temperature 130-1
90°C)...3 parts pigment...
・・・・・・・・・・・・・・・・・・・・・・・・
.........6 parts of unfoamed synthetic resin paint was applied to a thickness of 0.1 m771 using a flow coater.

Then, this three-layer coating film with a thickness of 0.3 mm was heated at 1800C.
After heat treatment for 10 minutes at a temperature of was completed.

Thereafter, a printed pattern with a matching pattern was formed on each coated film by gravure printing.

If necessary, the surface of the foamed resin molding layer may be screen printed with foamed paint to form a convex pattern after heat treatment, or gravure printed with ink containing a decomposition retardant, if necessary. The cosmetic properties can be enhanced by forming an embossed pattern after heat treatment.

As described above, according to the present invention, a uniform foamed resin molded layer can be provided directly on a substrate, and a high-quality decorative board with good heat retention and elasticity and strong adhesive strength between the substrate and the foamed molded layer is produced. can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged sectional view of a state in which a coating film is formed on a substrate surface according to the present invention, and FIG. 2 is a partially enlarged sectional view of a state in which the coating film shown in FIG. 1 is foamed. Explanation of symbols: 1...Substrate, 2...Coating film, 2a. 2b, 2c... Each paint layer having different foaming and softening temperatures for forming the coating film 2, 3... Foamed resin molding layer.

Claims (1)

[Claims] 1 A multilayer coating film is formed on the surface of a substrate such as plywood, hard fiberboard, particle board, wood wool cement board, etc. using a resin paint mixed with a foaming agent, and when forming this coating film, each layer has a different foaming softening temperature. Corresponding to the temperature gradient that occurs during heat treatment of the coating film, paints with a higher foaming and softening temperature are used from the lower layers to the upper layers, and by heat-treating the coating film obtained in this way, the foaming softening temperature is increased over all layers. A method for producing a decorative board having a foamed coating film, which is characterized by uniformly foaming the foamed coating film.