JPH0579482B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to oil finishing, which is one of the means for improving the appearance and durability of wood. This made mass production possible.

(Prior art and its problems) Oil finishing has traditionally been used for furniture, crafts, etc. as a finishing method that fully brings out the elegance of wood.

In other words, by infiltrating a drying oil such as linseed oil into the wood fiber structure, the oil intertwines between the wood fibers and hardens, emphasizing the shading and creating a deep wet color that cannot be achieved with simple painting. It gives a certain appearance.

However, in the conventional method, drying oil was applied from the surface and soaked in by oil sanding, which required repeating application and drying many times, resulting in extremely poor productivity.

On the other hand, in so-called WPC, which is made by injecting and curing synthetic resin into wood, which is currently widely used in industrial production of flooring materials, etc., the synthetic resin existing inside the wood undergoes radical polymerization by heating or radiation. It can be completely cured from scratch, but at that time, it is hardened homogeneously using a hot press to prevent the resin liquid from scattering, resulting in a glossy and transparent appearance that differs from that of an oil finish.

On the other hand, when aiming to improve industrial productivity by using an injectable liquid that is mainly composed of drying oil, even though it appears to be completely cured by heating and drying, etc.
Inside the material, there are many incompletely cured parts that have not undergone oxidative polymerization, and as they migrate to the front and back surfaces of the material due to changes in temperature and humidity, poor adhesion may occur if the material is integrated with the base plate, and the surface may become discolored or When applying a finishing coat, there are disadvantages such as color unevenness and poor coating, and contamination and cracking after long-term use.

(Object of the invention) The present invention has been made to improve the problems of the conventional art, and its purpose is to:
To provide a method for producing a wood decorative board capable of producing a large amount of wood decorative board with an oil finish finish that can be used for a long period of time.

(Means for Solving the Problems) In order to solve the above problems, the injected wood of the present invention is characterized in that the wood lamina has a drying oil and an unsaturated double bond, and is capable of radical polymerization. After impregnating the surface with a treatment solution containing a polymerizable substance, peroxide, and hardening agent as essential components and removing the treatment solution remaining on the surface, the surface is heated at a temperature of at least 40°C and at a wind speed of 1 m/sec or more. Expose to hot air for a certain period of time to harden.

According to claim 2, a thin wooden board is impregnated with a treatment liquid whose essential components are drying oil, a polymerizable substance made of a thermosetting resin, and a metal salt as a hardening agent, After removing the treatment liquid remaining on the surface, it is cured by exposing it to hot air at a temperature of at least 40°C and a speed of 1 m/sec or more for a certain period of time.

In claim 3, after adding a curing agent made of a metal salt internally to a thin wood board, a drying oil and a synthetic material having an unsaturated double bond and capable of radical polymerization are used. It is impregnated with a processing solution containing resin and peroxide as essential components, and after removing the processing solution that remains on the surface, it is exposed to hot air for a certain period of time to harden.

In claim 4, a hardening agent made of a metal salt is internally added to a thin wooden board in advance, and then a drying oil and a polymerizable substance made of a thermosetting resin are added as essential components. After the treatment liquid that remains on the surface is removed, it is exposed to hot air for a certain period of time to harden.

This technical method is adopted.

(Function) According to claims 1 and 2, a treatment liquid containing a drying oil, a polymerizable substance having an unsaturated double bond and capable of radical polymerization, a peroxide, and a curing agent as essential components; The treatment liquid, which has a drying oil, a polymerizable substance consisting of a thermosetting resin, and a metal salt as a curing agent, has a low molecular weight, so it can be easily molded into fine wood fiber structures by mechanical injection such as reduced pressure. Get inside.

After removing the excess treatment liquid on the wood surface, hot air is blown at a temperature of at least 40°C or higher and a speed of 1 m/sec or more for a certain period of time, so that the impregnated treatment liquid is
Cures without forming a film on the surface of the material.

Next, the hot air gradually penetrates deeply into the interior of the material due to its wind pressure, and comes into contact with the oxygen necessary to harden the drying oil present within the material, and reacts with the polymerizable substance to ensure hardening of the treatment liquid.

Furthermore, in claims 3 and 4, a hardening agent such as naphthenic acid metal salt or fatty acid salt that easily impregnates the wood is made to exist in the wood in advance, and then the treatment liquid is injected. Curing becomes easier.

As a result, oxidative polymerization is possible even inside the wood, and the variation in curing is reduced, so there is less migration of the treatment liquid inside the wood to the surface side, making it possible to harden the entire inside of the thin wood board.

In addition, the presence of the treatment solution of the present invention reduces hemicellulose and glinin in the wood components, which are defects caused by the scattering of hydroxyl groups in the wood components when untreated wood is exposed to hot air. , there is no deterioration of resins, etc., and the hydrophilic properties of cellulose, hemicellulose, etc. are modified, and the original performance and texture of the wood is not impaired, and the oil finish gives it the appearance of polished wood for a long time. I can do it.

(Example) The present invention will be described in detail below. The thin wood boards used in the present invention include oak, teak, zelkova, quince, ash, elm, cypress, etc. In this example, for example, oak veneer was used. If the wood thin board is too thin, the back side will be transparent, which is undesirable, but in order to take advantage of the unique texture of wood, it is preferably 0.8 mm or more.

In addition, it is possible to make use of the cracks on the back that occur during manufacturing, such as with rotary veneers or sliced veneers, or to perform treatments such as insizing on the back side of thin wood boards to increase the contact area between the treatment liquid and hot air, which will be described later. is preferred.

The treatment liquid used in the first invention includes various drying oils (coconut oil, castor oil, rice bran oil, soybean oil, tall oil, Cobalt,
Varnishes containing naphthenic acid or fatty acid salts such as lead, calcium, manganese, zircon, etc., in amounts appropriate to the drying conditions; A polymerizable substance consisting of a synthetic resin capable of radical polymerization,
For example, polymerizable monomers such as polyester, urethane, acrylic, and styrene, prepolymers, polymers, and other alkyd resins are mixed to increase water resistance and hardenability, and if necessary, colored translucent (dye) (transparent) treatment liquid.

In the second invention, instead of the polymerizable substance made of a radically polymerizable synthetic resin having one or more unsaturated double bonds, a thermosetting resin such as a phenolic resin or a melamine resin is added to the various drying oils, and an oil-based Mix it to the extent that it does not damage it.

It is necessary to adjust the viscosity of the treatment liquid depending on the wood species and thickness of the veneer, but in this case, a hydrocarbon solvent is added to adjust the injection.

The thin wood board is impregnated with a treatment liquid consisting of drying oil and a polymeric substance by mechanical injection such as under reduced pressure, and after removing the treatment liquid remaining on the surface, it is heated at a temperature of at least 40°C or higher for 1 m/min. It is cured by exposing it to hot air at a speed of at least 1 second (preferably at least 5 m/sec) for a certain period of time. Circulate the wind in such a way that the front and back surfaces of the thin wood boards are directly exposed to the hot air. The above hot air temperature is preferably preheated to 40°C in the initial stage and finally heated to 150 to 180°C for several hours. Warping and cracking can be prevented by combining cooling and preheating schedules, but at least the above If the process of exposing the material to hot air is not carried out for a predetermined period of time, the treatment liquid inside the material will not be able to completely harden, and the initial objective will not be achieved.

Further, in the third and fourth inventions, unlike the first and second inventions, naphthenic acid metal salts such as cobalt, lead, calcium, manganese, zircon, etc., lauric acid, stearic acid, etc. are used as a hardening agent in the thin wood board at a concentration of 20% or less. A curing agent that helps harden the drying oil is added internally to the material in advance, such as by impregnating it with an aqueous solution of fatty acid metal salts such as eg, by immersion or by injecting it under reduced pressure or pressure, and then drying it.

The treatment liquid used in the third invention does not require metal salts such as naphthenic acid metal salts such as cobalt, lead, calcium, manganese, and zircon or fatty acid metal salts from the treatment liquid of the first invention, does not contain them, or has no effect. A polymeric substance consisting of a radically polymerizable synthetic resin having one or more unsaturated double bonds (-C=C-) in the molecule, and the various drying oils mentioned above, as well as the various drying oils mentioned above. Add peroxide and adjust to suit drying conditions. The rest is the same as the first invention.

Furthermore, the treatment liquid used in the fourth invention is a treatment liquid of the second invention that does not require the above-mentioned metal salt as an essential requirement, and is obtained by adding a polymerizable substance made of a thermosetting resin to the various drying oils. The other aspects are the same as in the first invention.

According to the third and fourth inventions, since the hardening agent is impregnated into the wood in advance, homogeneous hardening of the treatment liquid is promoted down to the minute voids, and complete hardening is achieved and long-term use of the treatment liquid is made possible. This is something that can be done.
Further, since the curing agent is not mixed into the processing liquid or only a small amount is required, the viscosity of the processing liquid does not increase over a long period of time, which is preferable in terms of handling.

An example of using the treated wood obtained above as a flooring material is shown below. After gluing the above-mentioned treated wood to a base plate such as plywood, the surface is sanded and colored with oil stain, and then an oil finish-like paint that does not form a continuous coating on the surface layer, such as diluting the above-mentioned treatment liquid. A general-purpose resin liquid such as urethane, amino alkyd, etc.

Example 1 A varnish containing 50 parts by weight of tung oil and 50 parts by weight of unsaturated polyester resin was mixed with 0.5 parts by weight of 5% cobalt naphthenate salt, 0.5 parts by weight of 15% lead naphthenate salt, and 1.0 parts by weight of 50% peroxide solution. A treatment solution was prepared by adding 100% of the total amount.

The above treatment liquid was injected into a 2.1 mm oak veneer under a reduced pressure of 15 torr, and after removing the excess treatment liquid on the surface layer,
A treated veneer was obtained by placing it in a circulating hot air oven that can gradually raise the temperature from 40°C to 150°C for a total of 24 hours. The air speed of the above-mentioned circulating hot air stove is 3 m/sec.

Example 2 To a varnish containing 50 parts by weight of tung oil and 50 parts by weight of phenolic resin, 20 parts by weight of enamel toned to brown with various inorganic pigments (black, yellow, rust red, etc.) was added, and 5% of the color varnish was added. Add 0.12 parts by weight of cobalt naphthenate salt, 1.0 parts by weight of 15% lead chlorine naphthenate, and add 60 parts by weight of a hydrocarbon solvent for viscosity adjustment.
A treatment solution was prepared by adding parts by weight.

The above treatment liquid was injected into a 2.1 mm oak veneer under a reduced pressure of 15 torr, and after removing the excess treatment liquid on the surface layer,
A treated veneer was obtained by placing it in a circulating hot air oven that can gradually raise the temperature from 40°C to 150°C for a total of 24 hours. The circulating hot air stove used in Example 1 was used.

Example 3 A 2.1 mm oak veneer was impregnated with cobalt naphthenate salt at a concentration of 0.1% and dried.

A treatment liquid was prepared by adding 0.1 part by weight of 5% lead naphthenate to a varnish containing 50 parts by weight of tung oil and 50 parts by weight of phenolic resin, and adding 50 parts by weight of a hydrocarbon solvent for viscosity adjustment. The conditions for injection of the treatment liquid and hot air curing are the same as in Example 1.

(Effects) The first invention impregnates a thin wooden board with a treatment liquid that contains drying oil, a polymerizable substance that has unsaturated double bonds and is capable of radical polymerization, peroxide, and a hardening agent. In the second invention, the treatment liquid is impregnated with a drying oil, a polymerizable substance made of a thermosetting resin, and a treatment liquid containing a metal salt as an essential component as a curing agent. Because it has a low molecular weight, it is thoroughly impregnated into the thin wood board, and then heated at at least 40℃ after removing the treatment solution that remains on the surface.
Because the treatment is cured by exposing it to hot air at a speed of 1 m/sec or more for a certain period of time at a temperature above, the impregnated treatment liquid hardens without forming a film on the surface of the material, and the hot air penetrates deeply into the material due to its wind pressure. It can penetrate into the material and sufficiently harden it inside the material.

Furthermore, in the third and fourth aspects of the invention, since a curing agent such as a metal naphthenic acid salt or a metal salt of a fatty acid is interposed in the thin wood board in advance, the impregnation treatment liquid can be homogeneously and completely cured within the thin wood board. Therefore, there is an advantage in that the productivity of the elegant and high-class finishing method called oil finishing can be significantly improved, making it possible to increase industrial production of flooring materials and the like.

In addition, as mentioned above, since the treatment liquid penetrates deep into the material and hardens, there is no leakage of the treatment liquid even if there are changes in temperature or humidity, and there will be no adhesion defects, color unevenness, or coating defects during use. It has the advantage that it is less likely to become contaminated or crack, and the texture and appearance of the wood oil finish can be maintained for many years.

Claims (1)

[Scope of Claims] 1. A thin wood board is impregnated with a treatment liquid containing drying oil, a polymerizable substance having unsaturated double bonds and capable of radical polymerization, peroxide, and a curing agent as essential components, A method for producing a wood decorative board, which comprises, after removing a treatment liquid remaining on the surface, exposing the board to hot air at a temperature of at least 40°C and a speed of 1 m/sec or more for a certain period of time to cure it. 2. A thin wooden board is impregnated with a treatment liquid containing drying oil, a polymerizable substance consisting of a thermosetting resin, and a metal salt as a hardening agent, and the treatment liquid remaining on the surface is removed, and then heated to at least 40℃ or higher. At a temperature of 1
A method for producing a wood decorative board, which comprises curing it by exposing it to hot air at a wind speed of m/sec or more for a certain period of time. 3 After internally adding a hardening agent made of metal salt to the wooden thin board in advance, a treatment liquid containing a drying oil, a synthetic resin having unsaturated double bonds and capable of radical polymerization, and peroxide as essential components is applied. A method for producing a wood decorative board, which is characterized by impregnating the board, removing a treatment solution that remains on the surface, and then exposing it to hot air for a certain period of time to harden it. 4 After internally adding a hardening agent made of metal salt to the thin wood board, impregnate it with a treatment liquid whose essential components are drying oil and a polymerizable substance made of thermosetting resin, and remove the treatment liquid that remains on the surface. A method for producing a wood decorative board, which is then cured by exposing it to hot air for a certain period of time.