JPH03136806A - Patching and wood filling, and wooden plate subjected thereto - Google Patents

Abstract

PURPOSE:To obtain wood filling patching effect in one coating by a method in which foamable resin coating agent is used as the coating agent for patching and wood filling, and the whole surface of a wooden plate is coated with the agent. CONSTITUTION:The coating agent 8 composed of the compound containing active hydrogen, water, isocyanate compound and filler is especially preferable as the foamable coating agent for patching and wood filling. These compounds have the function generating carbon dioxide, while the coating agent 8 is made into resin by their mutual reaction. In order to achieve copy pressurizing, the length of the tip of a flexible member to be brought in contact with the object- surface to be coated is different due to the object to be coated and the coating agent 8, but it is normally 1-200mm and is preferably 10-50mm. For the angle of the flexible member 4 to the object 6 to be coated, knives 5, 5' are kept at 45-55 deg. in a normal knife coater, but they are kept at 40 deg.C and preferably at 15-30 deg. and more preferably at the acute angle of about 20 deg..

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for sealing and repairing recesses on the surface of a wooden board such as plywood in a process using a foamable resin coating agent, an apparatus therefor, The present invention relates to a repair and sealing wood board and a coating agent used in the method.

[Conventional technology] The surface of wooden boards such as boards, columns, and plywood has cracked surfaces of conduits and insect holes, so it has not been conventional practice to apply a repair agent or sealant for the purpose of repair or sealing. For these purposes, fillers such as abrasive powder and titanium paste, and repair agents such as various latexes, epoxy resins, and urethane resin paints are used.

[Problem to be solved by the invention]

However, the sealing agent and repair agent according to the above-mentioned conventional technology are each used separately, and therefore, although the sealing agent has a sealing effect, it is difficult to fill moth-eaten holes in wood etc. or large conduits. I could not do it. In addition, the recesses that need to be repaired, such as moth holes, vary depending on the type of material, hole size, depth, etc., and do not occur in a fixed location, so it is unavoidable to repair them manually using putty-like materials such as a trowel. It depends on the repair method used.

When attempting to repair the entire surface of a board or plywood using a conventional knife coater, even if a coating agent with a solid content of 100% is used, it cannot be filled to more than the volume of the recess to be repaired.
In addition, after application, the coating agent permeates into the pipe, causing eye discoloration, and the repair effect cannot be obtained with one filling, so conventional methods have been to repeat the repair work many times.

The present invention is intended to solve the above-mentioned problems regarding conventional sealing and repair work, and by using a foaming resin coating agent as a coating agent for both repair and sealing, and applying this to the entire surface of the wooden board. It is an object of the present invention to provide a coating method, an apparatus for the coating, a coating agent for the coating, and a wooden board to which the method is applied, which can provide a sealing effect and a repair effect with a single coating.

[Means for Solving the Problems] The method for sealing and repairing a wooden board surface of the present invention is to apply a foaming resin coating agent to the surface of a wooden board such as wood or plywood over the entire surface while applying pressure. The resin coating agent is then applied to the surface of the board, and then foamed to fill concave portions such as conduits, cracks, grooves, insect hole holes, press marks, etc. on the board surface with the resin coating agent.

In the present invention, the above-mentioned profile pressure refers to applying pressure to the coated surface with a trowel or the like after applying the coating agent. Place a doctor knife on the wooden board surface at a certain angle so that the tip of the knife is in parallel contact with the surface of the wooden board to be coated, and use the knife to squeeze the coating agent and apply it with the tip of the knife. Apply pressure to the surface of the wooden board.

Therefore, the coating device of the present invention, as means for applying a coating agent to a wooden board surface, includes a flexible member arranged at an appropriate angle to the wooden board surface for collecting the coating agent, and a flexible member disposed at an appropriate angle to the wooden board surface. and a means for applying pressure so that the tip portion thereof contacts the surface of the wooden board with an appropriate width.

In the present invention, a knife coater is usually used as the coating device.

The flexible member for dispensing the coating agent is typically made of a thin steel plate like a conventional doctor knife, but it is not limited to this, and may be roll-shaped, rod-shaped, half-moon-shaped in cross section, or Any material with appropriate flexibility may be used, even if it has a shape such as a crescent moon. For example, it may be a steel plate, a plate or molded product made of plastic or rubber such as fluororesin or vinyl chloride resin, or a doctor knife, etc. In the case of a plate-shaped flexible member,
The flexible member does not need to be a single plate, and may be used in two or three layers.More specifically, one or a combination of two or three steel plates with a thickness of around 1 mm may be used. Good.

The flexible member may be used at a fixed position, but the foaming resin coating agent can be applied to the application surface while moving up and down and left and right (copying).
It may be applied to the entire surface by applying pressure.

As a means of pressurizing the flexible member so that its tip comes into contact with the wooden board surface with an appropriate width, for example, an appropriate size is applied to the back side of the plate-shaped flexible member, that is, the side not in contact with the coating agent. It is recommended to arrange rolls with a diameter of 100 mm and pressurize the rolls with a hydraulic cylinder, etc. If the hydraulic cylinder is made adjustable in pressure, the pressure can be adjusted according to the object to be coated and the coating agent. be able to.

Note that if the pressing force is constant, it may be applied using a spring, a rubber elastic body, or the like.

If the flexible member is not a plate-like body, but a rubber molded body with a roll shape or a half-moon cross section, for example, by selecting a material with appropriate elasticity and pressurizing the molded body itself, It is preferable to obtain a predetermined contact area with the object to be coated.

The length over which the tip of the flexible member is brought into contact with the surface of the object to be coated in order to apply profile pressure varies depending on the object to be coated and the coating agent, but is usually about 1 to 200 mII+, preferably about 10 to 50 mm.

The angle of the flexible member with respect to the object to be coated is, in a normal knife coater, the knife is held at 45 to 55 degrees, but in the case of the present invention, it is 40 degrees, preferably 15 to 30 degrees, more preferably 20 degrees. It is best to hold it at an acute angle of about 100 degrees.

The foamable resin coating agent used in the present invention is a viscous liquid suitable for coating, and is embedded in concavities such as conduits, cracks, grooves, insect hole holes, press marks, etc. that exist on the surface of the wooden board at the time of coating. Any material that can be foamed to form a dense foam layer can be used.

Methods for forming the foam layer include a method that utilizes the generation of bubbles by a volatile liquid and a method that uses gas such as carbon dioxide gas. As a volatile liquid,
Fluorocarbon compounds such as trichloromonofluoromethane and trichlorotrifluoroethane, liquids such as methylene chloride, trichloroethane, acetone, and isopropyl ether can be used, and they can also be used in combination with silicone foam stabilizers to uniformly disperse volatile liquids. is also possible. For methods that generate gas such as carbon dioxide, sodium bicarbonate, calcium carbonate, guanidine carbonate, etc. can be used.

Particularly preferred as the foaming coating agent for repair and sealing of the present invention is a coating agent comprising an active hydrogen-containing compound, water, an isocyanate compound, and a filler. These compounds have the function of turning the coating agent into a resin (hardening) and generating carbon dioxide gas by reacting with each other. In other words, during the process in which an active hydrogen-containing compound and an isocyanate compound are cured by a urethane bonding reaction (reaction formula ■), carbon dioxide gas is generated by the urea bonding reaction (reaction formula ■) that occurs between water and the isocyanate compound, and this causes curing. It is trapped in the paint film to form a foamed paint film.

■ ~OH+ 0CN--~NHCO~ [Urethane bonding reaction] ■ ~NCO+ H,O÷ OCN~ → ~NHC
NH ~ + CO□ [Urea bonding reaction 1 In addition, isocyanate compounds also react with moisture in wood materials to quickly form a hardened film, preventing excessive penetration of the coating solution into the wood materials and reducing eye fading. It can be reduced.

Active hydrogen compounds include glycols such as polyethylene glycol and polypropylene glycol, polyester polyols, polyether polyols, acrylic polyols, epoxy polyols, polyols such as ethylene-vinyl acetate partially saponified polyol, and carboxylated styrene. Water-based latex such as butadiene latex, acrylic acid-acrylic acid ester copolymer emulsion, urea formaldehyde resin, melamine
There are water-soluble resins such as formaldehyde resin, phenol-formaldehyde resin, and polyamide borium chlorohydrin resin, and these resins can be used alone or in combination of two or more.

Isocyanate compounds include aromatic polyisocyanates such as diphenylmethane diisocyanate, tolylene diisocyanate, toridine diisocyanate, naphthalene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, xylene diisocyanate, hydrogenated xylylene diisocyanate, and block type. There are polyisocyanates and the like, and these can be used alone or in combination of two or more, but it is preferable to use polymethylene polyphenyl polyisocyanate from economical and environmental hygienic standpoints.

In addition, talc, clay, calcium carbonate,
Usual fillers such as titanium, mica, bentonite, asbestos, wood powder, soybean powder, blood powder, etc. can be used.

The blending ratio of the active hydrogen-containing compound and the isocyanate compound is determined depending on the type of the active hydrogen-containing compound, and is not generally limited, but for example, polyol is used as the active hydrogen-containing compound. In case, isocyanate group (NGO) and hydroxyl group (OH)
A ratio of NC010H=0.6 to 2.0, preferably 1.05 to 1.15 can be used. If the ratio is less than 0.6, the curing of the foamable resin coating agent will be insufficient, and if it is more than 2.0, curing will be delayed and there is a risk of causing discoloration due to excessive penetration and the like.

On the other hand, the proportion of water in the foamable resin coating is 30% by weight.
The moisture content is preferably 1 to 20% by weight. If the water content is more than 30% by weight, it will cause a delay in curing or the appearance of discoloration of the coating agent, and if it is less than 1% by weight, the fluidity necessary for the coating agent will be reduced. This is not preferable because the properties are lost and foaming becomes insufficient.

The foamable resin coating agent of the present invention can also contain a viscosity imparting agent such as sodium polyacrylate, cellulose ether, etc., if necessary.

[Function] According to the present invention, a foamable composition is used as a coating agent,
When applying the coating, a flexible member such as a coating knife was placed in contact with the surface of the wooden board, such as a board or plywood, from the line, so the coating agent filled into grooves, cracks, etc.
Due to the bending of the tip of the flexible member, surface pressure is applied and the compressed state is filled to more than the volume of the recess, and the coating agent that has entered the recess of the object drops to atmospheric pressure after passing through the flexible member. Therefore, filling can be performed without swelling the recesses to exceed their respective volumes and at the same time causing loss of appearance due to volumetric expansion due to foaming during the curing process of the coating agent, and filling and repair work can be completed in one step.

[Examples] Examples of the present invention will be described below with reference to the drawings.
The present invention is not limited to this.

FIG. 1 is a schematic diagram showing an example of the apparatus of the present invention, in which a ruler roll l for feeding a workpiece 6 such as plywood, a presser roll 2,
It consists of a push roll 3 for feeding the object to be coated 6 to the coating section and a knife coater type flexible member 4.

FIG. 2 is an explanatory diagram of a knife coater-type flexible member 4 serving as a coating means, and the flexible member 4 consists of two knives, a coating knife 5 and a backup knife 5'. , shows a state in which the knife 5 is pressed against the object 6 to be coated with strong pressure by the cylinder 7 via the roll 1o.

The foaming coating agent 8 is squeezed with the tip 9 of the knife 5,
In addition, since surface pressure is applied, point a is in a compressed state as shown in FIG. 3(a).

At point b, which has passed knife 5, the pressure returns to atmospheric pressure, so the third
As shown in Figure (b), the volume of the coating agent 8 filled in the recess becomes swollen.

During the curing process, as shown in Figure 3 (C), there is a balance between swelling due to foaming and shrinkage due to penetration of the coating agent into the wood and volatilization of moisture and volatile substances, resulting in a slightly convex shape. A coating film is formed on the surface. After that, finish it into a flat shape using a sander.

Example 1 15 parts of styrene/acrylic acid alkyl ester copolymer (Mitsubishi Yuka Pardish product, YJ-2741D), 15 parts of polypropylene glycol (PPG, molecular weight 750), viscosity imparting agent SN Thickener 808
(San Nopco product) 3 parts were mixed and stirred in advance.

To this mixture were added 0.15 parts of carbon black and 0.15 parts of red iron as pigments, and 30 parts of titanium oxide and 32 parts of calcium carbonate as fillers.

4.7 parts of water was added and stirred thoroughly.

This mixture was transferred from the tank to the mixing head by a snake pump. On the other hand, a crosslinking agent polymethylene polyphenyl polyisocyanate was transferred from the tank to the mixing head in an amount corresponding to 7% of the above mixture using a triple diaphragm pump.

The mixture and the crosslinking agent were instantaneously stirred by a bottle-shaped rotor rotating at 20 [10 rpm, and uniformly discharged onto a line by a traverser as a foaming coating agent for repair and sealing purposes.

Dispense the coating agent at a knife angle of 20 degrees and a contact width of 15 m.
The treated plywood was coated uniformly on the surface of the plywood using a knife coater, and then dried for 2 minutes in a dryer at 90"C, and the treated plywood was deposited. After being left to accumulate for 24 hours, the plywood was sanded and finished. Repairs and sealing plywood were obtained.

Example 2 1.5 parts of a silicone foam stabilizer (L-5421, a Nippon Unicar product) was mixed and stirred in advance with 25 parts of a phenolic resin (PS-153, a product of Honen Corporation) with a solid content of 80%.

Next, after mixing 0.5 parts of carbon black as a pigment, 30 parts of titanium oxide and 32 parts of clay as fillers, styrene-butadiene latex (Japan Synthetic Rubber Products, JSR-0
668) were gradually mixed.

These mixtures were mixed with 6 parts of polymethylene polyphenyl polyisocyanate as a crosslinking agent and 5% of a 53% aqueous solution of para-toluenesulfonic acid as a curing agent using the instant stirring device shown in Example 1, and discharged. It was applied to the plywood surface in the same manner as in 1, dried and deposited, and then sander-finished to obtain the repair and sealing plywood of the present invention.

Comparative Example 1 35 parts of vinyl acetate resin (Hoechst Synthesis product, Movinyl 12BT) was mixed with 35 parts of urea resin (11 Honen Corporation product, UW-063) with a solid content of 73%, and then mixed as a filler. 10 parts of wood flour, 0.15 parts of carbon black, 0.1.5 parts of red red iron, and 19.7 parts of kaolin clay (manufactured by Ueya Chikara Orin Kogyo, 5M kaolin) were gradually added and mixed to form a non-emitting resin. The coating agent was adjusted.

This coating agent was applied to the surface of the plywood in the same manner as in Example 1, dried and deposited, and then sanded to obtain a control plywood.

Comparative Example 2 The foaming coating agent prepared in Example 1 was applied to the plywood surface using a conventional knife coater (the knife tip was in line contact with the coating surface at a 45-degree knife angle to the coating surface) and dried. After sanding and sanding, a control plywood was obtained.

Table 1 shows the sealing effect and repair effect of each plywood produced according to the above Examples and Comparative Examples. In addition, "No r" in the repair effect tank indicates that there is no eye loss and there is a repair effect.

Table 1 [Effects of the Invention J] In the repair method of the present invention, sealing and repair were conventionally performed in two steps, but sealing and repair can be completed in the second step without causing the same inconvenience. Therefore, the labor and complicated work required for repair becomes easier, and work efficiency improves. In addition, the use of a foaming resin coating agent not only does not cause the occurrence of eye discoloration, but also provides smoothness on the surface of the wooden board, so a satisfactory sealing and repair effect can be obtained with a single filling operation. It has various advantages, such as being able to easily and economically produce wood boards of good quality.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing an example of the coating device of the present invention. Figure 2 is a side view for explaining a part of the knife coater. Figures 3 (a), (b), and (c) are examples of repair recesses. FIG. In the figure, l... 2... 3... 4... 5.5' 6... 8... Ruler roll Presser roll Push roll Flexible member... Knife Painting agent for coated objects

Claims (5)

[Claims] (1) After applying a foaming resin coating agent to the entire surface of a wooden board such as wood or plywood while applying pressure, it is foamed to remove conduits, cracks, grooves, insect hole holes, etc. on the board surface. A method for repairing and sealing a wooden board surface, which comprises filling recesses such as marks with the resin coating agent. (2) As a means for applying a foamable resin coating agent to a wooden board surface, a flexible member for spreading the coating agent is arranged at an angle of 40 degrees or less with respect to the surface to be applied, and the flexible member 1. A coating device comprising means for pressurizing a member so that its tip portion contacts a wooden board surface with a width of 1 to 200 mm. (3) As a means for applying a foaming resin coating agent to the surface of a wooden board, a doctor knife-shaped flexible member for spreading the coating agent is placed at an angle of 15 to 30 degrees with respect to the surface to be applied. , the tip of the flexible member is attached to the surface of the wooden board by 10 to 5
3. The coating device according to claim 2, further comprising means for applying pressure so as to contact each other with a width of 0 mm. (4) After applying a foaming resin coating agent to the entire surface of a wooden board such as wood or plywood while applying pressure, it is foamed to remove conduits, cracks, grooves, insect hole holes, etc. on the board surface. A repair and sealing wood board characterized by filling recesses such as marks with the resin coating agent. (5) A foamable resin coating agent for repair and sealing, characterized by comprising a foamable resin component containing an active hydrogen-containing compound, water, and an isocyanate compound, and a filler.