JPS597035A - Manufacturing method of resin reinforced fiberboard - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing resin-reinforced fiberboard mainly used for furniture materials, construction materials, etc., and particularly relates to a method for producing resin-reinforced fiberboard that is mainly used for furniture materials, construction materials, etc. It relates to a method for efficiently producing plates.

It has been known to apply and impregnate a wooden or mineral fiberboard with a synthetic resin liquid, heat-press it, etc., and harden the impregnated resin liquid to increase the surface hardness, bending strength, etc. of the fiberboard.

However, in the conventional resin impregnation method using coating, the resin and liquid do not penetrate sufficiently into the center of thick fiberboards, and the center remains unimpregnated. However, even with this method, it was not possible to strengthen the core evenly, resulting in delamination in the center due to bending, etc., and in the case of furniture materials, problems such as weak bonding strength of dowels at the end of the wood, etc. were common.

On the other hand, as a method of impregnating the fiberboard with resin to the center, there is a method of impregnating it by immersing it in a resin solution for a long time.
According to this method, the impregnation process takes a long time and productivity is poor, and a large amount of resin liquid is contained in the front and back surfaces and the end surface, which is uneconomical.

The present invention has been made in view of the above-mentioned conventional drawbacks,
By laminating multiple fiberboards coated and impregnated with thermosetting synthetic resin liquid, even if the thickness exceeds 15m7, there will be no unreinforced part in the center. 4) An object of the present invention is to provide a method for efficiently producing a uniformly reinforced resin-reinforced fiberboard by an impregnation method using coating.

In order to achieve this objective, the structure of the present invention has a dry specific gravity of 0.4. After coating and impregnating at least one side of the following fiberboards with a thermosetting synthetic resin liquid, a plurality of the fiberboards are laminated with their resin-impregnated surfaces in contact with each other, and then the laminated fiberboards are compressed and heated. This method is characterized in that the impregnating resin liquid permeates the entire fiberboard and hardens to unify the whole.By doing so, the resin-reinforced fiberboard is evenly strengthened to the center by impregnation by coating. It is produced according to the law.

Here, different properties may be imparted to the surface layer portion and the interior of the laminated fiberboard by changing the type of resin liquid applied and impregnated into the fiberboard.

Hereinafter, the present invention will be explained in detail based on the drawings.

First, as shown in FIG. 1(a), for example, the thickness is
Dry at 7" or more, preferably 12 mm or more.
Wooden or mineral fiberboard with JtO1 strength of 0.4 or less
, 11 . . , by applying and impregnating thermosetting synthetic resin liquid 2 on each side at a ratio of 200 to 600 mm in terms of resin solid content using a spray, flow coater, roll coater, or the like. The fiberboard used here may be either dry or wet.

The synthetic resin liquid 2 used here is 7E/-/L/.

Melamine, urea resin, etc. are used, but they must be mixed with water or other appropriate solvent so that they can quickly penetrate into the surface layer of the fiberboard. The above thermosetting resin liquid may contain vinyl chloride, acrylic, polyester,
A thermobJ plastic resin such as ethylene vinyl acetate may be mixed and used.

The reason why we use fiberboard 1 with a dry specific gravity of 0.4 or less is because the fiberboard 1 has a specific gravity higher than 0.4: Because it is dense, it is necessary to sufficiently penetrate the resin liquid in the resin impregnation method by coating. This is because it is not possible.

The amount of the resin liquid applied depends on the thickness of the fiberboard 1, but if it is about 7mm thick, the amount of the resin liquid applied is 2° in terms of solid content.
00-300. %, 10. , 300-40 for thick ones
0~. A thickness of 400 to 600 is appropriate for a 1514 m thick fiberboard; if the thickness is less than this, it is difficult to uniformly strengthen the fiberboard to the center, and it is difficult to integrate it with other fiberboards by heat pressing later. On the other hand, if a larger amount is applied and impregnated, the whole becomes hard, resulting in poor workability, and an excessive amount of resin is generated, which is uneconomical.

Furthermore, in the present invention, the type of resin liquid to be applied and impregnated does not have to be the same type on both sides as shown in Fig. 1, but may be such that one side is mainly made of melamine resin and the other side is mainly made of phenol resin. You may change it and use it.

In particular, by changing the resin liquid applied to both sides in this way, it can be used for furniture top boards, etc., where hardness is required on the surface side and some elasticity is required on the inside. As shown in FIG. 2(a), one side of the fiberboard 10 is coated and impregnated with a resin liquid 2a mainly composed of melamine resin, and the other side is coated and impregnated with a mixed resin liquid 2b of phenol resin and vinyl acetate resin. As shown in figure (b), melamine resin liquid 2
Two fiberboards 1, 1 with the side impregnated with a facing outward,
The surfaces impregnated with the mixed resin liquid 2b may be brought into contact with each other, laminated, and heat-pressed. In addition, when stacking three or more sheets, a third
As shown in the figure, both surfaces of the intermediate fiberboard 1 may be impregnated with the mixed resin liquid 2b.

Furthermore, when two fiberboards are to be laminated, at least one side thereof may be coated and impregnated with a resin liquid, and the resin liquid-impregnated surfaces may be brought into contact with each other and laminated.

Next, a plurality of fiberboards 1゜1... impregnated with the resin liquid are laminated as shown in Fig. 1(b), Fig. 2(b), and Fig. 3(b), and the laminated fibers are The plate 6 is heated and pressed by the press device 4 or the like. As a result, the resin liquid 2 impregnated into the surface layer of each fiberboard 1 penetrates into the interior, and the resin is cured, thereby integrating the entire laminated fiberboard 6.

The conditions for heating and pressing are as follows: In order to allow the resin liquid 2 to migrate and penetrate into the interior, the heating and pressing conditions are such that the thickness of the entire laminated fiberboard 6 is reduced to about A to A before pressing, and the temperature is Depending on the resin, the entire resin can be cured in a short time by performing the curing at 150°C to 250°C. In fact, when using an undried fiberboard made by wet papermaking, the fiberboard can be simultaneously dried by this heating and pressurization.

Note that the heat-pressing device may be a flat plate press or a continuous press such as a belt press, and is not particularly limited.

The resin-reinforced laminated fiberboard 6 obtained in this way can be evenly reinforced up to the center even if the laminated thickness is 15 Tnm or more, and since the resin impregnation treatment is a coating method, the resin can be impregnated in a short time. Since it can be strengthened, it can be produced efficiently. In addition, by changing the type of resin liquid applied and impregnated on both sides of the fiberboard 1, different performances can be imparted to the surface layer and the inside of the laminated fiberboard 5, so it is possible to easily create a reinforced fiberboard with desired properties. can be manufactured.

Next, examples of the present invention will be described.

<Example 1> Specific gravity 0.25. A mixed resin aqueous solution of urea resin/vinyl acetate resin -'70/30 (solid content ratio) was applied to a dry wood fiberboard with a thickness of 15 mm at a ratio of 400 powder in terms of resin solid content on each of the front and back sides. After coating and impregnating with
When heated and pressed for a minute, a resin-reinforced laminated fiberboard having the physical properties shown in the table below was obtained.

<Example 2> Specific gravity 0.35. Phenolic resin/vinyl acetate resin -85/15 (
A mixed resin aqueous solution with a solid content ratio of 300 powders (calculated as resin solid content) was applied and impregnated on each of the front and back surfaces.
After laminating the sheets, 210° until the entire thickness is 15 mIn.
C. for 5 minutes to obtain a resin-reinforced laminated fiberboard having the physical properties shown in Table C.

<Example 3> Specific gravity 0.25. Thickness 15. A melamine resin aqueous solution was coated on one surface of a dry wood fiberboard of 200 m in the solid content at a ratio of 400 to 400. Apply and impregnate a mixed resin aqueous solution with a solid content ratio of 400%,
After stacking two sheets of this material with their back sides facing one side,
When heated and pressed at 210'C for 5 minutes until the whole became 20 mm thick, the surface was harder and more resistant to abrasion than that of Example 1, and the center part was relatively easy to drill holes, etc., and had moderate elasticity. A resin-reinforced fiberboard was obtained.

As described above, according to the present invention, resin-reinforced fiberboard with a thickness of 15 m or more can be efficiently produced, and therefore resin-reinforced fiberboard suitable for furniture materials, construction materials, etc. can be provided at low cost. . In addition, since different properties can be imparted to the surface layer and the interior of the resin-reinforced fiberboard, it also has the advantage of easily producing a resin-reinforced fiberboard with physical properties depending on the intended use.

[Brief explanation of drawings]

FIGS. 1(a) and (b) are manufacturing process diagrams illustrating embodiments of the present invention, FIGS. 2(a) and (b), and FIG. 3(a).
) and (b) are manufacturing process diagrams showing modified examples, respectively. 1...Fibreboard, 2+ 2a+ 2b...Resin liquid, 6...
Laminated fiberboard, 4...press equipment.

Claims (2)

[Claims] (1) After coating and impregnating at least one side of a fiberboard with a dry specific gravity of 0.4 or less with a thermosetting synthetic resin liquid, a plurality of the fiberboards are laminated with their resin-impregnated surfaces in contact with each other. . A method for manufacturing a resin-reinforced fiberboard, which comprises: then compressing and heating the laminated fiberboard to infiltrate the entire fiberboard with an impregnating resin liquid and harden it to integrate the entire fiberboard. (2) Claim (1) characterized in that different properties are imparted to the surface layer and the interior of the laminated fiberboard by changing the type of resin liquid applied and impregnated on each side of the fiberboard.
A method for producing a resin-reinforced fiberboard as described in Section 1.