JPH08100399A - Production of fiberboard - Google Patents

Abstract

PURPOSE: To produce a lightweight fiberboard having a high strength by forming raised parts in prescribed sites of a fiber mat, then hot-pressing the fiber mat and converting the raised parts into high-density parts. CONSTITUTION: A raw material for a fiberboard comprising wood fibers, a phenol resin and paraffin is scattered on a belt conveyor to form a fiber mat M, which is then cut through a brushing roll and/or a shaving roll arranged so as to intersect the mat conveying direction at right angles. Raised parts MA are formed in prescribed sites on the surface of the fiber mat M or a template having a punched prescribed pattern is brought into contact with the surface of the fiber mat M to cut the mat or scatter the raw material for the fiberboard. The raised parts MA on the surface of the fiber mat M are then formed and the fiber mat M is then set in a press 8 having a bottom force 9 and a top force 10 to perform the thermo compression bonding treatment. The raised parts MA of the fiber mat M are compressed and converted into high-density parts FA to obtain the objective fiberboard.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fiber board used for building boards and the like.

[0002]

2. Description of the Related Art Weight can be reduced by lowering the density of fiberboard,
Workability, heat insulation and sound absorption are improved. However, on the other hand, the problem of insufficient strength of the fiberboard arises because of the low density. In order to make up for the lack of strength of such a low-density fiberboard, a structure has been conventionally provided in which a cut is made at a predetermined position of the fiberboard, and an aggregate having higher strength than the fiberboard is tightly fitted into the cut. (JP-A-5-263497).

[0003]

However, the above-mentioned prior art requires a step of making a notch after manufacturing the fiberboard and a step of tightly fitting the aggregate in the notch, which is very troublesome to manufacture. In addition, since the fiber board and the aggregate are not integrated, there is a problem that the reinforcing effect is small.

[0004]

As a means for solving the above conventional problems, the present invention hot-presses a fiberboard raw material mat M having a raised portion MA formed at a predetermined location to remove the location of the raised portion MA. The present invention provides a method for manufacturing a fiberboard F which is a high-density portion FA. The raised portion MA of the fiber board raw material mat M is, for example, a brushing roll (13) or a shaving roll (7) at a portion other than the raised portion MA forming portion.
It is formed by cutting using.

[Fiberboard Raw Material] The fiberboard raw material used in the present invention is mainly composed of fibers and a synthetic resin binder. As the fibers, wood fibers such as pulp fibers, waste paper fibers, wood wool and wood chips are mainly used, but other natural fibers such as bamboo fibers, hemp fibers and cotton fibers, polyethylene fibers, polypropylene fibers, polyester fibers, polyamide fibers, Synthetic fibers such as acrylic fibers, inorganic fibers such as glass wool, rock wool, and ceramic wool may be used, and two or more kinds of the above fibers may be mixed. A desirable wood fiber is a wood waste fiberized. Examples of the synthetic resin binder include urethane resin, melamine resin, thermosetting acrylic resin, urea resin,
Phenolic resin, epoxy resin, thermosetting synthetic resin such as thermosetting polyester, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, polystyrene, poly Vinyl acetate, fluororesin, thermoplastic acrylic resin, thermoplastic polyester, thermoplastic polyamide, thermoplastic urethane resin, acrylonitrile-
Butadiene copolymer, styrene-butadiene copolymer,
There are thermoplastic synthetic resins such as acrylonitrile-butadiene-styrene copolymers, ethylene-propylene copolymers, ethylene-propylene terpolymers, ethylene-vinyl acetate copolymers, or the like, or synthetic resins produced in place of the above synthetic resins. Prepolymers such as urethane resin prepolymer, epoxy resin prepolymer, melamine resin prepolymer, urea resin prepolymer, phenol resin prepolymer, diallyl phthalate prepolymer, acrylic oligomer, polyvalent isocyanate, methacrylic ester monomer, diallyl phthalate monomer , Oligomers,
A monomer or the like is used, and two or more kinds of the above synthetic resin binders may be mixed. Other than the above raw materials, if desired, a wax, paraffin, silicone or other water repellent, pigment,
A third component such as a coloring material such as a dye may be added.

[Production of Fiber Board] In the production of fiber board,
The synthetic resin binder is usually added to the fibers in an amount of 2 to 20% by weight based on the solid content, and if desired, the third component is further added and mixed to prepare a fiber board raw material. The fiberboard raw material is manufactured into a fiberboard by an ordinary dry method. That is, the fiber board raw material is sprinkled on a base such as a belt conveyor to form a mat having a predetermined thickness, and the mat is hot-pressed by a press molding machine to produce a fiber board. Before, a raised portion is formed at a predetermined position of the formed mat. To form a raised portion on the mat, a portion other than the raised portion forming portion is usually cut by a brushing roll or a shaving roll. In a usual dry method, the mat is formed on a belt conveyor, so in order to cut a predetermined portion of the mat, the brushing roll or the shaving roll is placed above the belt conveyor with the roll axis direction orthogonal to the mat conveying direction. Further, it is arranged so as to be movable up and down, and when the cutting portion of the mat comes under the brushing roll or the shaving roll, the roll descends to cut the cutting portion of the mat. Further, when a brushing roll is used, a method is also applied in which a template in which a predetermined pattern is punched is brought into contact with the surface of the mat, and the pattern is cut from above with a brushing roll according to the pattern. Further, in the present invention, in order to form a raised portion at a predetermined portion of the mat, the fiberboard raw material may be sprinkled on the raised portion forming portion instead of the above cutting method. In this case as well, a method may be applied in which the template is brought into contact with the surface of the mat, the fiber board raw material is sprayed, and then the template is removed. The fiberboard raw material mat having the raised portions formed at the predetermined locations as described above is set in a press molding machine and hot pressed. The pressing conditions vary depending on the type of fiber used, the type of synthetic resin binder, etc. For example, in the case of wood fiber and phenol resin, the pressing temperature is 170 ° C to 220 ° C and the pressing pressure is 5 to 35 kgf /
cm ² , the pressing time is about 0.5 to 5 minutes, the compression ratio is usually about 1/10 to 1/20 in the raised portion and 1 in the non-raised portion.
/ 2 to 1/5, and the density is usually 0.7 to 0.92 at the raised portion, and 0.25 at the non-raised portion.
It is set to about 0.60.

[0007]

When the fiberboard raw material mat M having the raised portion MA formed at a predetermined location is hot-pressed, the compression rate is different between the raised portion MA and other locations, and the compression rate is higher at the raised portion MA.
It becomes lower in other parts. Therefore, the location of the raised portion MA of the obtained fiber board F becomes a high density portion, and the other locations become a low density portion, and the fiber board F is reinforced by the high density portion and lightened by the low density portion. In addition, excellent processability and heat insulation and soundproofing are provided. In the production of the fiber board F, if a brushing roll (13) or a shaving roll (7) is used when forming the raised portion MA, the side wall of the raised portion MA becomes a slope S, and the raised portion at the time of hot pressing. The MA is prevented from collapsing, the compression efficiency is improved, and a high density is obtained in this portion.

[0008]

【Example】

[Embodiment 1] This embodiment is shown in FIGS. In the figure
(1) is a belt conveyor that moves in the direction of the arrow in FIG.
On the belt conveyor (1), as shown in FIG. 1, fiberboard raw material R is sprayed from three stages of fiberboard raw material spraying ports (2, 3, 4) to form a mat M. The composition of the fiberboard raw material is as follows. Wood fiber 94 wt% Phenolic resin 5 〃 Paraffin 1 〃 The mat M formed in this way is then placed on the belt conveyor (1) with the roll axis direction orthogonal to the mat conveying direction as shown in FIG. The surface is shaving and smoothed by a pre-shaving roll (5), and further pre-pressed by a roll pressing device (6) as shown in FIG. The mat M prepressed in this way is then arranged at the cutting position above the belt conveyor (1) so that the shaving roll (7) is vertically movable with the roll axis direction orthogonal to the mat conveying direction as shown in FIG. ) Is lowered to cut a predetermined place. As described above, since the mat M is preformed, the shape of the mat M does not collapse during the above cutting, and it is possible to easily cut at a predetermined position. If a higher compression ratio is required,
That is, when the height of the raised portion becomes high, the preliminary pressing may be performed again after the cutting, and the step of performing the cutting again may be repeated several times.

Thus, the mat M having the raised portion MA formed as shown in FIGS. 5 and 6 is manufactured. In FIGS. 5 and 6, MB is a cutting portion or non-raised portion,
As shown in FIG. 6, a slight slope S is formed on the side wall of the raised portion MA. As shown in FIG. 7, the mat M is set in a press molding machine (8) consisting of a lower mold (9) and an upper mold (10), and hot pressed for 3 minutes at 180 ° C. and 30 kgf / cm ^2. It At this time, since the slope S is formed on the side wall of the raised portion MA of the mat M as described above, the slope S prevents the raised portion MA from collapsing due to the press pressure, and even in the narrow raised portion MA. Compressed efficiently. In this way, the fiber board F as shown in FIG. 8 is obtained. In the fiber board F, the compression ratio at the raised portion MA is 1/15 and the density becomes the high density area FA of 0.92,
The compression ratio at the non-raised portion MB is 1/3, and the density is 0.30.
Is the low density portion FB. Table 1 shows the relationship between the density and the physical properties of the fiber board F.

[0010]

[Table 1]

According to Table 1, in the case of this embodiment, the fiberboard F
High density part FA has a density of 0.92 and a bending strength of 675 kg.
Since f / cm ² and wood screw holding power are 110 kg / piece, which is a solid reinforcing portion, and as shown in FIG. 8, the high density portion FA is arranged vertically and horizontally at the plate periphery and the middle portion, The fiberboard F of the example has excellent bending strength and torsional strength both in the longitudinal direction and in the transverse direction as a whole, and is useful as a core material of a door having only one edge supported by a hinge. As shown, the decorative material D is attached to both surfaces of the fiber board F. In this embodiment, the width of the shaving roll and the descending time of the shaving roll can be variously changed to form various patterns of raised portions, that is, high density portions.

[Embodiment 2] This embodiment is shown in FIGS. 10 to 14. A fiberboard raw material having the following formulation is prepared. Wood fiber 80% by weight Polyethylene fiber 13 〃 Melamine resin 5 〃 Silicon resin 2 〃 As in Example 1, the above fiberboard raw material is used as a belt conveyor (1).
The mat M is formed by spraying on the surface, the surface of the mat M is smoothed by a pre-shaving roll in the same manner as in Example 1, and pre-pressed by a roll pressing device. A template sheet (11) punched with a predetermined pattern (12) as shown in FIG. 10 is brought into contact with the surface of the mat M pre-pressed in this way, and the belt conveyor (1) as shown in FIG. By exposing a brushing roll (13) arranged so that the roll axis direction is orthogonal to the mat conveying direction and movable up and down, the pattern sheet (11) on the surface of the mat M is exposed to the pattern (12). The fluffed part is brushed to stand up, and then the fluffed part is sucked and removed by the suction device (14). Thus, the mat M having the raised portions MA and the non-raised portions MB formed in the pattern as shown in FIG. 12 is obtained. The mat M was placed in the same press molding machine (8) as in Example 1 at 150 ° C. and 25 kgf / cm ^2.
By hot pressing for 3 minutes under the conditions described above, the fiber board F having the high density portion FA and the low density portion FB is manufactured as shown in FIG. In the fiber board F, the compression ratio of the high density portion was 1/12 and the density was 0.80, and the compression ratio of the low density portion was 1 / 3.5 and the density was 0.47. It is also useful as a door core material.

FIG. 14 shows an apparatus for continuously brushing the mat of this embodiment. In the figure, the template sheet (1
1) is an endless guide roll (15A, 15B, 15C15D,
15E, 15F, 15G), which is suspended and guided, comes into contact with the surface of the mat M being conveyed on the belt conveyor (1), and by the first stage brushing roll row (13A, 13B, 13C) The part exposed to the pattern of the template sheet (11) on the surface of M is fluffed, and further fluffed by the second stage brushing roll row (13D, 13E), and then the fluff suction device ( 14) Aspirate the fluff. The first-stage brushing roll trains (13A, 13B, 13C) and the second-stage brushing roll trains (13D, 13E) are respectively coated on the chambers (16, 17), and the chambers (16, 17) include cyclones and The suction path (18, 19) connecting to the air filter is connected. In this embodiment, various patterns of ridges, that is, high-density portions can be formed by changing the pattern of the template sheet.

Other than the above embodiment, the high density portion F of the fiberboard F
A and the low-density portion FB may be arranged so as to cross each other as shown in FIG. 15, or may be arranged at any other place. In addition, the mat may be cut by a brushing roll after shaving by a shaving roll, or by a shaving roll after brushing by a brushing roll.

[0015]

Therefore, in the fiber board of the present invention,
Since the low density portion is reinforced with the high density portion, it is lightweight and has excellent workability and heat insulation and soundproofing. Since the high density portion is formed at the same time as the hot pressing of the fiberboard F, it is not necessary to separately attach the reinforcing material, the manufacturing process is rationalized, and the position, shape, size, etc. of the high density portion are also improved. The degree of freedom is great, and fiberboard having various patterns of high density parts can be manufactured using the same production line.

[Brief description of drawings]

 1 to 9 relate to Example 1 of the present invention.

FIG. 1 is an explanatory diagram of a mat forming process.

FIG. 2 is an explanatory diagram of a preliminary shaving process

FIG. 3 is an explanatory diagram of a preliminary pressing process

FIG. 4 is an explanatory diagram of a shaving process.

[Figure 5] Plan view of mat

6 is a sectional view taken along line AA in FIG.

FIG. 7 is an explanatory diagram of a hot press process

FIG. 8: Fiberboard cross-sectional view

FIG. 9 is an explanatory diagram of a use as a door core material. FIGS. 10 to 13 relate to a second embodiment of the present invention.

FIG. 10 is an explanatory view of a template contact state.

FIG. 11 is an explanatory diagram of a brushing process.

FIG. 12: Plan view of mat

FIG. 13 is a perspective view of a fiberboard.

FIG. 14 is an explanatory diagram of a continuous brushing device.

FIG. 15 is a plan view of a fiberboard of another embodiment.

[Explanation of symbols]

 R Fiberboard material M Matt MA Raised part MB Non-raised part F Fiberboard FA High density part FB Low density part 7 Shaving roll 8 Press molding machine 13 Brushing roll

Claims (4)

[Claims] 1. A method for producing a fiber board, characterized in that the fiberboard raw material mat having a raised portion formed at a predetermined location is hot-pressed to make the location of the raised portion a high density portion. 2. The method for producing a fiberboard according to claim 1, wherein the raised portion of the fiberboard raw material mat is formed by cutting a portion other than the portion where the raised portion is formed. 3. The method for producing a fiberboard according to claim 2, wherein the cutting of the fiberboard raw material mat other than the raised portion forming portion is performed using a brushing roll and / or a shaving roll. 4. The method for producing a fiber board according to claim 1, wherein a stencil having a predetermined pattern is brought into contact with the surface of the fiber board raw material mat to form a raised portion by cutting or scattering the fiber board raw material.