JP3523940B2 - Core material for sandwich panel and sandwich panel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sandwich panel core material and a sandwich panel made of polyethylene or polypropylene.

[0002]

2. Description of the Related Art Heretofore, core materials for sandwich panels have generally been made of paper such as corrugated cardboard and metal such as aluminum foil.

[0003]

However, the core materials made of paper or metal are weak against water and cannot be used outdoors for a long period of time. Further, the metal core material is vulnerable to acids and alkalis, and has various problems such as high manufacturing cost.

A water-resistant polyethylene or polypropylene resin is considered there. These resins are excellent not only in water resistance but also in chemical resistance and have an advantage that they can be recycled. However, polyethylene and polypropylene have poor adhesiveness to other substances, and are not useful for general purpose adhesives such as vinyl acetate emulsion. Also, some expensive instant adhesives using a primer have poor workability due to immediate drying, and when the bonding area is large, sufficient adhesive force cannot be obtained.

A first object of the present invention is to provide a core material for a sandwich panel, which is made of polyethylene or polypropylene to enhance water resistance and chemical resistance, and which can be adhered to a face material.

A second object of the present invention is to provide a sandwich panel using a core material made of polyethylene or polypropylene.

[0007]

In order to achieve the above object, the present invention has a large number of cell walls and a connecting plate that connects the cell walls to each other, and extends substantially in the same direction and is adjacent to each other. The core body made of polyethylene or polypropylene in which a large number of cells are formed, and a porous base material having a melting point higher than that of polyethylene or polypropylene are provided, and the connecting plate has unevenness on the surface side, and a part of the base material. The core material for sandwich panel is characterized in that the core material is fused to the concave portion of the connecting plate.

Further, the present invention is made of polyethylene or polypropylene having a large number of cell walls and a connecting plate for connecting the cell walls to each other, and extending in substantially the same direction and forming a large number of adjacent cells. Of the core material and an expanded punching metal having a melting point higher than that of polyethylene or polypropylene, the expanded punching metal has an inclined piece, and the core material main body in a state where a part of the inclined piece is embedded in the surface side of the connecting plate. Provided is a core material for a sandwich panel, which is fused to.

Furthermore, the present invention has a large number of cell walls which have a large number of cell walls and a connecting plate which connects the cell walls to each other and has irregularities formed on the surface thereof, and which extend in substantially the same direction and are adjacent to each other. A core material body made of polyethylene or polypropylene in which is formed, a porous base material having a melting point higher than that of polyethylene or polypropylene and a part of which is fused in the recess of the connecting plate, and the base material is placed on the connecting plate. And the bonded surface material,
The present invention provides a sandwich panel comprising:

The present invention is also made of polyethylene or polypropylene having a large number of cell walls and a connecting plate connecting the cell walls to each other, and extending in substantially the same direction and forming a large number of adjacent cells. Of the core material and a large number of inclined pieces formed of a material having a melting point higher than that of polyethylene or polypropylene. A part of the inclined pieces embedded in the connecting plate is fused to the core material and expanded. A punching metal and a face material that is bonded to the connecting plate via an expanded punching metal,
The present invention provides a sandwich panel comprising:

[0011]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

In the embodiment shown in FIG. 1, a sandwich panel core material 10 has a rectangular core material body 12 and a porous thin base material 14 fused to both surfaces of the core material body 12. . The core body 12 is made of polyethylene, and is composed of a plurality of corrugated plates 12a that are cell walls and a plurality of flat plates 12b that are fused or adhered to both sides of the corrugated plates 12a. Of course, the corrugated plate 12a and the flat plate 12b may be integrally formed from the beginning by extrusion molding. The cells 16 having a mountain-shaped cross section defined by the corrugated plate 12a and the flat plate 12b are adjacent to each other and extend in the same direction. The base material 14 is a nonwoven fabric made of polyester and has a thickness of, for example, 0.11 mm (17 g per square meter in terms of basis weight). The melting point of polyethylene, which is the material of the core body 12, is 102 to 110 degrees Celsius, and the melting point of polyester is 250 to 264 degrees Celsius, that is, higher than the melting point of the core body 12. The base material 14 is not limited to a non-woven fabric, but may be a woven fabric, a knitted fabric, a wire net, or the like. Further, as the material thereof, appropriate natural fiber, synthetic resin, inorganic material, metal or the like can be used.

When manufacturing the core material 10, first, the nonwoven fabric 14 is aligned with both ends of the cell wall of the core material body 12. Next, the core material body 12 is heated and pressed at a temperature of about 150 degrees Celsius from above and below with a flat plate-shaped heating plate (not shown). The heat of the heating plate is transferred to the core body 12 via the nonwoven fabric 14. Then, when the transmission temperature slightly exceeds 100 degrees Celsius, the polyethylene, which is the material of the core body 12, begins to melt. Since polyethylene has a low thermal conductivity, it melts conveniently only in the area in contact with the hot platen. Then, heating and pressing are performed until polyethylene having a cell column height of about 1.3 mm is melted. The melted polyethylene flows into the openings of the porous nonwoven fabric 14 and entangles with the fibers, gradually closing the openings (see FIG. 3). Further heating reduces the opening area of the cell 16,
The thickness of the edge gradually increases. After that, the core material body 12 is solidified by natural cooling. As a result, the core material body 12 and the nonwoven fabric 14 are firmly integrated to complete the core material 10.

As shown in FIG. 2, when a face material 18 made of an appropriate material is adhered to the core material 10, it can be used as a sandwich panel 20. The face material 18 is, for example, a wood fiber board having a thickness of 2.5 mm. To apply the face material 18, first, an adhesive 22 such as ethylene vinyl acetate emulsion (water-based general-purpose product) is applied to one surface of the face material 18. Next, the face material 18 and the non-woven fabric 14 are aligned so that the side coated with the adhesive 22 faces the non-woven fabric 14. When a predetermined pressure is applied to the face material 18 from above and below in this state, the adhesive 22 starts to permeate the nonwoven fabric 14. The adhesive 22 that has permeated then flows into the back surface side through the thick portion at the cell end. By the so-called anchoring effect, the face material 18 is indirectly and surely bonded to the core body 12 via the nonwoven fabric 14. Completed wood panel 20
Is ideal for partitions and doors around water such as bathrooms and washrooms.

FIG. 4 is a partial perspective view showing an enlarged core material according to another embodiment of the present invention.

As shown in the figure, the core material 30 has a polypropylene core material body 32 and a porous base material 34. A large number of rectangular cells 36 defined by cell walls 35 arranged in a grid pattern are adjacently extended in substantially the same direction. The melting point of polypropylene, which is the material of the core body 32, is about 160 degrees Celsius. In this embodiment, a stainless steel wire net is used as the base material 34 instead of the non-woven fabric. Its thickness is 0.09 mm. The cross-sectional shape of the core material is not limited to the corrugated shape or the grid shape, and may be an appropriate shape including various polygons.

In manufacturing the core material 30, first, the wire mesh 34 as the base material is applied to both ends of the cell wall 35 of the core material body 32. From this state, the core body 32 is heated and pressed from above and below with a heating plate (not shown) heated to about 170 degrees Celsius. The heat of the heating plate is transferred to the polypropylene core material body 32 through the wire net 34. When this transmission temperature reaches around 160 degrees Celsius, polypropylene, which is the material of the core body 32, melts and gradually begins to coat the wire net 34. Since polypropylene also has low thermal conductivity like polyethylene, the resin locally melts. In the embodiment shown in FIG. 4, polypropylene surrounds each wire forming the wire netting 34 at a ratio of 90% or more.

To manufacture a sandwich panel using this core material 30, an epoxy resin is applied to one surface of a stainless steel surface material (not shown) having a thickness of 0.7 mm, for example.
Then, when the applied side is aligned with the core material 30 and a predetermined pressure is applied, the face material is firmly adhered to the core material. By the way, when the sandwich panel manufactured as described above was subjected to a fracture (tensile) test, 100% fracture was found in the core material (the panel of this construction is particularly useful for non-structural panels of automobiles). .

In the embodiments of FIGS. 1 to 4, the base material is fused to one end or both ends of the cell wall of the core material, but the base material may be fused to one flat surface of the core material.

In the embodiment shown in FIG. 5, the core material 40 is
It has a polyethylene core material body 42 with a thickness of about 5 mm. The core material main body 42 is composed of two thin upper and lower connecting plates 42a having a thickness of about 0.3 mm, and a large number of cell walls 42b having the same thickness provided between the upper and lower connecting plates 42a. . Then, the connecting plate 42a and the cell wall 42b define a large number of cells 44 having a rectangular cross section. On the surface side of the connecting plate 42a, a polyester non-woven fabric 46 having a thickness of about 0.1 mm, which is a base material forming a part of the core material 40, is fused. A wire mesh (not shown) is used to fuse the non-woven fabric 46 to the surface of the connecting plate 42a. That is, a wire mesh of about 0.1 mm square is placed on the surface of the connecting plate 42a, and the wire mesh is pressed against the surface by a heating means such as a heating plate. The heating temperature at this time is about 150 degrees Celsius, and after the surface of the connecting plate 42a is melted by an appropriate thickness, for example, 0.3 to 0.5 mm, the pressurization is stopped to cool and solidify. As a result, as shown in FIG. 6, the non-woven fabric 46a located at a position where the wire mesh partially digs into the connecting plate 42a is fused to the connecting plate 42a, while the non-woven fabric 46b located at other positions is connected to the connecting plate 42a. No fusion to 42a. Then, a part of the non-fused non-woven fabric 46b works effectively when it is bonded to the face material. When a sandwich panel is manufactured using a face material made of an appropriate material, the adhesive used for bonding the face material penetrates into the non-fused non-woven fabric 46b and surrounds the fiber for good adhesion. Be effective. The permeation of the adhesive is positively performed because the nonwoven fabric 46 is porous and has high wettability.

In the above embodiment, the wire mesh is used to promote the fusion bonding of the non-woven fabric 46. However, the heating roller is provided with an embossing or groove of an appropriate shape, and the connecting plate 42a as shown in FIG.
It is also possible to form irregularities on the surface of.

In another embodiment shown in FIG. 7, a core material 50
Has a polypropylene core body 52 having a thickness of about 5 mm. Similarly to the above-described embodiment, the core material main body 52 has two thin upper and lower connecting plates 52a, for example, a connecting plate 52a having the same thickness of 0.3 mm, and the connecting plate 52a having the same thickness and being orthogonal to the connecting plate 52a. It is composed of a large number of cell walls 52b provided therebetween. The connecting plate 52a and the cell wall 52b define a cell 54 having a rectangular cross section. The core material 50 further includes a punching metal 56 made of aluminum that is fused and bonded to at least one surface of the connecting plate 52a. As shown in FIG. 8, the punching metal 56 is a rectangular metal sheet in which small cuts are made and then expanded to form a large number of parallelogrammic openings 58. Is about 2.8
The cell wall (slanting piece) 60 defining the opening 58 is inclined at an angle of 70 degrees, for example.

In order to fuse the expanded punching metal 56 to the core material body 52, first, the punching metal 56 is placed on the surface of the connecting plate 52a of the core material body 52. After mounting, the punching metal 56 is pressed against the connecting plate 52a by an appropriate heating means (not shown) such as a smooth heat roller. The heating temperature of the heating means at this time is about 180 degrees Celsius. And, for example, at a pressure of about 0.5 kgf / cm2, about 20 to 3
When heating and pressing for 0 seconds, the inclined piece 6 of the punching metal 56
0 is partially immersed in the surface of the fused connecting plate 52a.
When the punching metal is immersed in an appropriate amount, the heating and pressing operation is stopped and the core material body 52 is solidified by natural cooling.

As shown in FIG. 7, when a channel material 62 made of, for example, aluminum is adhered to a core material 50 composed of a core material body 52 and a punching metal 56 using an adhesive 64 having a large cohesive force, such as an epoxy resin. The adhesive 64 surrounds a portion where the punching metal is not embedded and exerts a good adhesive function. Of course, a metal plate is used as the connecting plate 52.
It is also possible to adhere to the entire surface of a. When strength is required for punching metal, stainless steel should be used as the material.

[0025]

EFFECT OF THE INVENTION Since the core material and sandwich panel of the present invention use polyethylene or polypropylene as the main material, they are excellent in water resistance and chemical resistance, and when a face material is attached, a base material is used. Since it indirectly adheres via the interposition, it is possible to surely and easily adhere to various kinds of face materials. Incidentally, since polyethylene and polypropylene are supplied in large quantities as by-products of the petrochemical industry, there is an advantage that the material can be easily secured and the unit price is low.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an example of a core material.

FIG. 2 is a partially cutaway perspective view of a sandwich panel produced by using the core material of FIG.

FIG. 3 is a partially enlarged perspective view of the sandwich panel shown in FIG.

FIG. 4 is a partially enlarged perspective view showing a modified example of a core material for a sandwich panel.

FIG. 5 is a perspective view of a sandwich panel core material according to an embodiment of the present invention.

6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is a perspective view according to another embodiment of the present invention.

8 is a partial perspective view of a stretch punching metal used for the core material shown in FIG.

[Explanation of symbols]

12 core material body 14 Non-woven fabric (base material) 16 cells 18 surface materials 20 wood panels 22 Adhesive 32 core material 34 Wire mesh (base material) 35 cell wall 36 cells 42 core material body 44 cells 46 non-woven fabric 52 core material 54 cells 56 Extending punching metal 60 cell wall (sloping piece)

Claims (4)

(57) [Claims] 1. A core material for a sandwich panel, comprising a large number of cell walls and a connecting plate connecting the cell walls to each other, and forming a large number of adjacent cells extending in substantially the same direction. And a porous base material having a melting point higher than that of polyethylene or polypropylene, the connecting plate has irregularities on the surface side, and a part of the base material is the connecting plate. A core material for a sandwich panel, wherein the core material is fused inside the recess. 2. A sandwich panel core material comprising a large number of cell walls and a connecting plate for connecting the cell walls to each other, and forming a large number of adjacent cells extending in substantially the same direction. And a stretched punching metal having a melting point higher than that of polyethylene or polypropylene. The stretched punched metal has an inclined piece, and a part of the inclined piece is on the surface side of the connecting plate. A core material for a sandwich panel, which is fused to the core body in a state of being embedded in the core material. 3. A sandwich panel comprising a large number of cell walls and a connecting plate connecting the cell walls to each other and having irregularities formed on the surfaces thereof, and extending in substantially the same direction and being adjacent to each other. A core material body made of polyethylene or polypropylene in which a large number of cells are formed, a porous base material having a melting point higher than that of polyethylene or polypropylene, and a part of which is fused inside the recess of the connection plate, and the connection plate And a face material adhered via the base material to the sandwich panel. 4. A sandwich panel having a large number of cell walls and a connecting plate connecting the cell walls to each other, wherein a large number of adjacent cells extending in substantially the same direction are formed. A core material main body made of polyethylene or polypropylene, and a core material formed of a material having a higher melting point than polyethylene or polypropylene and having a large number of inclined pieces, with a part of the inclined pieces embedded in the connecting plate. A sandwich panel comprising: an expanded punching metal fused to a main body; and a face material bonded to the connecting plate via the expanded punching metal.