JP2001121630A - Lightweight panel material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight panel material used as furniture, a building material or other general industrial material, having high strength and capable of being produced easily. SOLUTION: A pair of core materials 2A each formed by integrally forming a plate-shaped surface part 21 on a core part having a honeycomb structure by the press molding of a paper raw material are superposed one upon another so that the surface parts 21 become outside to obtain a lightweight panel material 1 wherein surface materials 3 are integrally provided to the surfaces of a core material 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to furniture, building materials such as ceiling materials, flooring materials, partitioning materials and the like, and more particularly to light-weight materials used for general industrial use. The present invention relates to a lightweight plate material in which a surface material made of a synthetic resin such as a fiber-reinforced synthetic resin sheet is integrally provided on the surface of the honeycomb structure.

[0002]

2. Description of the Related Art Conventionally, as a lightweight plate material, a metal or paper honeycomb made of aluminum or the like, or a foam made of a synthetic resin such as polyurethane or polystyrene is used as a core material.
There is a material in which a metal plate or a fiber-reinforced thermoplastic resin sheet is adhered to the surface thereof with an adhesive as a surface material. For example, JP-A-7-233630 discloses that a fiber-reinforced thermoplastic resin sheet is bonded to both front and back surfaces of a honeycomb core using an adhesive such as a hot melt adhesive, an epoxy adhesive, or a urethane adhesive. A plate for a concrete formwork is disclosed. However, in the case of a plate material in which the surface material is bonded to the surface of the core material using an adhesive in this manner, the surface strength depends on the adhesive strength between the core material and the surface material, and is higher than the adhesive strength of the adhesive. In addition, depending on the material of the core material and the surface material, a treatment such as applying a primer to the bonding surface was required in order to enhance the adhesion between the two, and the bonding operation was complicated. Further, in the case where the synthetic resin foam is used as the core material, the surface strength is obtained by the self-adhesive bonding strength of the foam, and the strength cannot be higher than the bonding strength. Further, JP-A-7-88988 discloses that
Laminate a fiber-reinforced thermoplastic resin plate with melted resin on both sides of a core material having a honeycomb structure, and sandwich it with a hot plate from the outside so that the laminate is pressed against the core material Discloses a laminated molded product in which a molten resin is permeated into fibers or porous portions of a core material to integrate the laminate with the core material. In this case, the core and the laminate as the surface material are bonded by melting the resin of the laminate and penetrating into the core, so that the adhesive strength is higher than in the case of using the above-described adhesive, The bonding operation can also be simplified. However, the surface material is only adhered at the end face of the partition wall of the honeycomb structure of the core material, and there is a problem that sufficient adhesive strength is not necessarily obtained.

[0003]

SUMMARY OF THE INVENTION In view of the above, the present invention provides a paper honeycomb structure as a core material provided with a surface material made of a synthetic resin such as a fiber-reinforced synthetic resin sheet as a surface material. Another object of the present invention is to provide a lightweight plate material which has a high bonding strength between the core material and the surface material, a high surface strength, and can be easily manufactured.

[0004]

In order to achieve the above-mentioned object, in a lightweight sheet material according to the present invention, as a core material, a sheet material is press-formed into a core having a honeycomb structure to form a plate-like surface portion. It is characterized in that a surface material made of synthetic resin is provided integrally on the surface of the core material in a state where the synthetic resin is impregnated on the surface portion of the core material. . In this lightweight sheet material, since a core material in which a core portion and a plate-shaped surface portion are integrally formed by press-molding a paper raw material is used, the strength of the core material itself, a large number of paper sheets This core material and the surface material made of synthetic resin provided on its surface are extremely large compared to ordinary par-per honeycomb etc. bonded in a honeycomb shape, and the synthetic resin of the surface material is a plate-like material on the surface of the core material. By being impregnated into the surface part, it is firmly adhered to, and thus, the synthetic resin is impregnated into the plate-like surface part of the core material, whereby the surface of the lightweight plate material is formed into a fiber-reinforced synthetic resin layer over almost the entire surface. Thus, the strength of the core material is further enhanced, and as a result, the obtained plate material is lightweight and extremely strong.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 shows a lightweight plate 1 according to the present invention.
FIG. 2 is a partially cut-away perspective view showing one embodiment of the present invention, and FIG. The lightweight plate 1 is made of a light core 2 made of paper and having a honeycomb structure, and surfaces 3 and 3 made of synthetic resin are integrally provided on both sides of the core 2. Is the surface material 3
Are bonded together in a state where the surface portions 21, 21 of the core material 2 are impregnated.

The core member 2 is manufactured using paper as a raw material. For example, as shown in FIG. 3, a plate is formed on an end face of a core portion 22 having a honeycomb structure so as to close a cavity of the core portion. In the illustrated embodiment, two cores 2A, 2A having the same shape are formed by using the cores 2A formed integrally with each other, as shown in FIG. , 21 are placed outside, and the end faces of the core portions 22 having a honeycomb structure are integrally bonded by an adhesive such as an epoxy resin adhesive, a polyurethane adhesive, or a vinyl acetate adhesive. Things. The core material 2A in which a plate-shaped surface portion is integrally formed with the core portion 22 having the honeycomb structure is manufactured by press-molding a paper raw material. Add an additive such as to make a wet mat of a predetermined thickness, and shape it by hot pressing,
By forming a large number of concave portions 23 on one side in a honeycomb shape, the core portion 22 having a honeycomb structure is formed into a plate-like surface portion 2.
1 is integrally formed. In addition, this paper core material 2A can also be manufactured using waste paper as a raw material.
In this case, it is manufactured by adding an additive to a pulp obtained by stirring waste paper with water and press-molding the same as above.

As described above, the core member 2A in which the plate-shaped surface portion 21 is integrally formed with the core portion 22 having the honeycomb structure.
The adhesive strength between the core portion 22 and the surface portion 21 is remarkably higher than that of a normal paper core having a surface portion bonded to a honeycomb core formed by bonding a large number of paper sheets in a honeycomb shape. When forming the concave portion 23 of the core portion 22 by press molding, the partition wall portion and the plate-shaped surface portion 21 of the core portion 22 are compression-molded.
Its strength is extremely high. Further, in the above embodiment, the core 2 is made of two cores 2A which are superimposed and bonded together, so that the strength is further increased. The core material 2A is always 2
It is not necessary to use the sheets stacked on top of each other, one core material 2A
Only the core material 2 may be used, and the surface material 3 may be provided on one surface portion 21, or two core materials 2 </ b> A, 2 </ b> A may be overlapped and used as the core material 2 as shown in FIG. Even in such a case, it is not always necessary to provide the surface material 3 on both surfaces thereof, and the surface material 3 may be provided on only one surface of the core material 2 depending on the use and required strength.

In the present invention, the honeycomb structure of the core portion 22 has a hexagonal continuous cross-sectional shape as shown in the figure, as well as a square, rhombic, triangular, circular, etc. continuous cross-sectional shape. It includes all things.

As described above, in the lightweight plate material of the present invention, since the core portion 22 and the plate-shaped surface portion 21 use the paper core material 2A integrally formed by press molding, the core portion 22 The strength of the joint between the core portion 22 and the surface portion 21 is remarkably superior to that of a general paper honeycomb in which the surface portion is bonded with an adhesive. The surface portion 21 of the core material 2 and the surface material 3 are firmly adhered to each other in a state where the synthetic resin of the surface material 3 is impregnated, and the plate-like surface portion 21 of the core material 2 is impregnated with the synthetic resin. Since it is reinforced by forming a reinforced synthetic resin layer, the strength of the lightweight plate 1 is significantly large.

The surface material 3 provided on the surface of the core material 2 is not particularly limited, and the synthetic resin constituting the surface material 3 is not particularly limited, and may be a thermoplastic resin, a thermosetting resin, or an ultraviolet ray. Any of a cured resin and the like can be used. Examples of the thermoplastic resin include polyolefin resins such as polypropylene and polyethylene, amide resins such as nylon 6 and nylon 66, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, polyphenylene sulfide, and ABS resin. Examples of the thermosetting resin include an unsaturated polyester resin, an epoxy resin, and polyurethane, but are not limited thereto.

In the case where the synthetic resin constituting the surface material 3 contains an inorganic filler, the strength of the surface material 3 is improved, and the surface portion 21 of the core material 2 is impregnated with the synthetic resin. It is more preferable because the strength of the plate material 1 can be further increased in combination with the formation of the fiber-reinforced synthetic resin layer. As the inorganic filler contained in the surface material 3,
Examples include, but are not limited to, fiber reinforcements such as glass fibers, carbon fibers, aramid fibers, and boron fibers, and inorganic fillers such as mica and talc.

As a method of forming the surface material 3 on the surface of the core material 2, for example, in the case of a surface material made of a thermoplastic resin, as shown in FIG. A fiber reinforced thermoplastic resin sheet 31 formed by compounding the fiber reinforced material is superimposed on both surfaces or one surface 21 of the core material 2, and the hot plates 10, 1
By hot pressing at a temperature equal to or higher than the melting point of the thermoplastic resin which is the matrix of the fiber-reinforced thermoplastic resin sheet 31 by sandwiching the thermoplastic resin, the thermoplastic resin is melted and fluidized, and a part of the melted thermoplastic resin is melted. Is impregnated into the surface portion 21 of the core material 21 and the fiber-reinforced thermoplastic resin sheet 31 is melt-bonded to the surface portion 21 of the core material 2, and then the thermoplastic resin is cooled and solidified, whereby the surface portion 21 of the core material 21 is cooled.
The surface material 3 made of the fiber-reinforced thermoplastic resin sheet 31 can be integrally provided on the surface of the core material 2 in a state where the thermoplastic resin is impregnated on the surface portion 21 of the core material 2. For example, when a sheet made of polypropylene containing glass fibers is used as the fiber-reinforced thermoplastic sheet 31, for example, a pair of hot plates 10, 10 heated to 250 to 270 ° C.
Hot-pressing between them melts and bonds the glass fiber reinforced polypropylene sheet to the surface of the core material 2.

The pressure applied when the fiber-reinforced thermoplastic resin sheet 31 is melt-bonded to the surface of the core material 2 by hot pressing is about 19.6 × 10 ^{4 to} 39.2 × 10 ⁴ Pa (gauge pressure). is there. If the pressing force is too low, the bonding strength between the surface material 3 made of the fiber-reinforced thermoplastic resin sheet 31 and the core material 2 may not be sufficient, and if the molding pressure is too high, the core material at the time of pressing may be insufficient. 2 may be destroyed. The core member 2 used for the lightweight plate member 1 of the present invention is formed by integrally forming the plate-shaped surface portion 21 on the core portion 22 having the honeycomb structure by press molding as described above. Since the partition wall portion and the plate-like surface portion of the core portion 21 are sometimes compression-molded, the strength of the core material 2 itself is larger than that of a normal paper honeycomb core.
When the fiber-reinforced thermoplastic resin sheet 31 is melt-bonded to the surface thereof by hot pressing, the pressure can be increased at a higher pressure than when a normal paper honeycomb core is used as the core material, and the core material 2 and the surface material can be pressed. 3 also has high adhesive strength.

As the fiber-reinforced thermoplastic resin sheet, there are a sheet containing continuous reinforcing fibers and a sheet containing discontinuous reinforcing fibers, and any of them can be used. As the one containing the continuous reinforcing fibers, a one-way fiber reinforced thermoplastic resin sheet in which a thermoplastic resin is impregnated into a fiber sheet in which continuous fibers are aligned in one direction, or a thermoplastic resin in a woven fabric made of reinforcing fibers. There is a multi-directional fiber reinforced thermoplastic resin sheet impregnated, and examples of the sheet containing the discontinuous reinforcing fiber include a sheet using a chopped strand mat of glass fiber. Various types of these fiber-reinforced thermoplastic resin sheets are commercially available, and can be appropriately selected and used depending on applications and required strength. These fiber-reinforced thermoplastic resin sheets may be used alone, or a plurality of sheets may be laminated on the surface of the core material 2 to adjust the thickness and strength of the surface material 3.
Thus, the plurality of fiber-reinforced thermoplastic resin sheets are
When laminating the unidirectional fiber reinforced thermoplastic resin sheet, for example, as shown in FIG. 6, a plurality of unidirectional fiber reinforced thermoplastic resin sheets 31a,
By laminating 31b while changing the direction of the fiber (indicated by an arrow in the figure), the strength of the obtained lightweight plate 1 can be improved. In order to laminate a plurality of fiber-reinforced thermoplastic resin sheets 31, it is not always necessary to laminate and press all the sheets at the same time, but it is also possible to laminate and press in a plurality of times.

Further, instead of using the fiber-reinforced thermoplastic resin sheet 31 in which the thermoplastic resin is previously impregnated with the reinforcing fiber such as glass fiber as described above, for example, as shown in FIG. When the synthetic resin film or sheet 33 on one or both sides of the fiber mat 32 or the like is stacked on one or both sides of the core material 2 and hot-pressed, the fiber mat 32 and the synthetic resin film or sheet 33 are integrated. At the same time, the surface material 3 can be provided on the surface of the core material 2.

Instead of the fiber-reinforced thermoplastic resin sheet 31 as described above, a synthetic resin sheet in which a thermoplastic resin is used as a matrix and an inorganic filler such as talc or mica is filled therein is used. By hot pressing, the surface material 3 can be provided on the surface of the core material 2.

When the surface material 3 is made of a thermosetting resin, a prepreg having a thermosetting resin as a matrix, which is impregnated in advance into a fiber base material, dried and hardened appropriately, and used as a B stage is used. Used, after hot pressing in the same manner as in the case of the fiber reinforced thermoplastic resin sheet,
By cooling, the thermosetting resin is melted, fluidized, impregnated into the surface portion 21 of the core material 2 and thermoset, thereby strengthening the surface of the molten core material 2 with the fiber-reinforced thermosetting resin. The material 3 can be provided integrally with the thermosetting resin impregnating the surface portion 21 of the core material 2.

Further, in addition to the method of pressing the above-mentioned thermoplastic resin sheet or thermosetting resin prepreg on the surface of the core material 2, for example, unsaturated polyester resin, epoxy resin, polyurethane, etc. The liquid synthetic resin may be applied to the surface portion 21 of the core material 2 to impregnate the surface portion 21 with the synthetic resin, and the reinforcing material 3 made of the synthetic resin may be provided on the surface. Also in this case, the reinforcing material 3 containing the filler can be provided on the surface of the core material 2 by including the inorganic filler in the liquid synthetic resin. Further, a reinforcing material such as a glass fiber mat is overlapped on the surface portion 21 of the core material 2, and unsaturated polyester,
The surface portion 21 of the core material 2 is impregnated with the synthetic resin by applying a liquid synthetic resin such as an epoxy resin or polyurethane to a predetermined thickness and then curing the synthetic resin. Surface material 3 made of resin
Can also be provided.

[0019]

EXAMPLES Examples of the present invention will be described below, but these examples do not limit the present invention in any way.

The waste corrugated paper is pulped by stirring it with water, and a mixture obtained by adding additives such as a sizing agent and a paper strength agent to a mold is poured into a mold, and excess water is dewatered to form a wet mat. After the wet mat is pre-pressurized and dewatered by a cold press, a plate-shaped surface portion is integrally formed on a core portion having a honeycomb structure having a continuous hexagonal cross section having an outer diameter of about 20 mm obtained by hot pressing. Two honeycomb core boards with a thickness of about 9 mm and an apparent specific gravity of about 0.25 are overlaid with their surface parts outside, and the end faces of the core parts are integrally bonded with a vinyl acetate adhesive. The core material was used. On the front and back of this core material, unidirectional glass fiber reinforced polypropylene sheet,
By changing the direction of the fiber by 90 ° and stacking two by two,
Hot plate temperature 250-270 ° C., pressure 19.6 × 10 ⁴ -39.2 × 10 ⁴ Pa (gauge pressure) sandwiched between hot plates from above and below
After hot pressing for 5 minutes, cooling was performed in a pressurized state to obtain a lightweight plate material in which a surface material made of glass-reinforced polypropylene was provided on the surface of the core material. The obtained plate was a very high-strength lightweight plate.

[0021]

As described above, the lightweight plate according to the present invention is formed by pressing a paper material into a core having a honeycomb structure and a plate-like surface integrally formed on the surface of the core. A surface material made of a synthetic resin is integrally provided in a state where the synthetic resin of the surface material is impregnated on the surface of the core material, and the core material and the plate-like surface portion are formed by press-molding a paper material. Since the core material is integrally formed with the core material, the strength of the core material itself is extremely large as compared with a normal perper honeycomb, and the core material and the surface material made of synthetic resin on the surface are The surface of the core material is impregnated with the synthetic resin so that the surface of the core material is firmly bonded, and the surface of the core material is impregnated with the synthetic resin to form a fiber-reinforced synthetic resin layer. The strength of the core material is further increased, In an amount, moreover is extremely intensity greater than the conventional composite plate using a conventional paper honeycomb core. In addition, this lightweight plate material can be manufactured by laminating a fiber-reinforced thermoplastic resin sheet or prepreg impregnated with a thermosetting resin on reinforcing fibers on the surface of the core material, and then hot-pressing it. It can be manufactured very easily as compared with the case where the surface material is bonded by the agent.

[Brief description of the drawings]

FIG. 1 is a partially broken perspective view showing one embodiment of a lightweight plate material according to the present invention.

FIG. 2 is a partially enlarged cross-sectional view of the lightweight plate.

FIG. 3 is a partially enlarged perspective view of a core material used for the lightweight plate material of the present invention.

FIG. 4 is an explanatory view showing a manufacturing method of one embodiment of a core material used for a lightweight core material of the present invention.

FIG. 5 is an explanatory view of a hot press showing an example of a method for manufacturing a lightweight plate material according to the present invention.

FIG. 6 is an explanatory view showing one example of a method for laminating a fiber-reinforced thermoplastic resin sheet on a core material.

FIG. 7 is an explanatory view showing one example of a method of laminating a glass mat and a thermoplastic resin sheet on a core material.

[Explanation of symbols]

1: lightweight plate material, 2 and 2A: core material: 3: surface material, 10: hot platen, 21: surface portion, 22: core portion, 23: concave portion, 31,
31a, 31b: fiber reinforced thermoplastic resin sheet, 32:
Fiber mat, 33: synthetic resin film or sheet.

Claims (5)

[Claims] 1. A surface material made of synthetic resin is provided on the surface of a core having a plate-shaped surface integrally formed with a core having a honeycomb structure by press-forming a paper raw material. A lightweight sheet material characterized by being provided integrally with a synthetic resin impregnated in a surface portion of a core material. 2. A pair of core members in which a plate-shaped surface portion is integrally formed on a core portion having the honeycomb structure, and the core portions are integrally bonded with an adhesive by superposing the core members with their surface portions outside. The lightweight plate material according to claim 1, wherein the surface material is integrally provided on a surface of the core material. 3. The lightweight plate according to claim 1, wherein the surface material is made of a synthetic resin containing an inorganic filler. 4. The lightweight plate according to claim 3, wherein the inorganic filler is a fiber reinforced material. 5. The lightweight plate material according to claim 1, wherein a surface material is provided by superposing a fiber-reinforced thermoplastic resin sheet on the core material and heating and pressing the sheet.