JPH1086160A - Manufacture of foamed heat insulation board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a foamed heat insulation board employing an open injection method without employing a closed injection method and, in this instance, prevent the occurrence of deformation such as warpage without using another new sealing material or an outer peripheral frame sustaining mold. SOLUTION: The manufacturing method of a foamed heat insulation board comprises the steps of inserting an outer peripheral frame 7 between an upper surface board 5 and a lower surface board 6, defining a closed space by fastening integrally the upper and lower surface boards 5, 6 and outer peripheral frame 7 and, at the time of injecting foaming resin liquid, after fabricating a tentative assembly of the upper and lower surface boards 5, 6 and outer peripheral frame 7 in a foaming mold including a lower mold 1 and an upper mold 3, absorbing and separating the upper surface board 5 by absorption materials set on the upper mold 3, and open-injecting foaming resin liquid 9 into a space defined by a lower surface board 6 stayed in the lower mold 1 and the outer peripheral frame 7. Also, it is preferable that a temperature difference is previously made in a preheating temperature between the upper surface board 5 and the lower surface board 6 by the upper and lower molds 1, 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a heat insulating material for building materials, refrigerators, vending machines, showcases, cooler boxes and the like. Inject the foaming resin stock solution into the space,
The present invention relates to a method for manufacturing a foamed heat insulating board which has simpler and more uniform foam properties than a foamed heat insulating board to be foam-filled.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a foamed heat insulating board having a sandwich structure having an upper and lower surface plate and an outer peripheral frame, the upper and lower surface plates are arranged in parallel in upper and lower molds and between them. The outer frame was set, and the foamable resin stock solution was injected into the space formed by these to foam-fill and cure.
At that time, particularly in the case of foamed heat insulating boards used for building materials, etc., the material of the surface sheet is often relatively thin and weak, and the handling is often poor. After filling the undiluted solution, an open injection method in which the upper surface plate is covered, and the upper mold is closed and locked cannot be adopted. As shown in FIG. 2, after the upper, lower surface plate and the outer peripheral frame are assembled in the foaming mold. In addition, a closed injection method in which a foamable resin stock solution is filled from an injection hole provided on the upper surface or the side surface has to be adopted, and has the following disadvantages.

[0003] Since the filling property of the foam is inferior, the density distribution of the foam is poor and the amount of the foaming resin stock solution used increases. There is a possibility that the foaming pressure is locally increased to easily cause deformation, and that the foam may leak from the joint. It is necessary to process the injection hole in the upper mold, the surface plate or the side mold, and the outer peripheral frame, and a treatment member for the hole after the injection and foaming is required. That is, FIG. 2 shows a cross-sectional view of one embodiment of the conventionally used closed injection method, in which the upper, lower surface plates 5 and 6 and the outer peripheral frame 7 are assembled between the lower die 1 and the upper die 3. After that, the injection head 8 is inserted through the injection hole 5b of the upper surface plate.
More, for example, inject a rigid polyurethane foam stock solution,
Although foam filling is performed, foaming of the foamable resin stock solution progresses while flowing to the periphery because the injection hole is fixed in one place, the fluidity is reduced, and a uniform foam filled heat insulating plate is formed. I couldn't get it.

[0004] When manufacturing the above-mentioned foamed heat insulating board having a sandwich structure, the edges of the upper and lower surface plates 5 and 6 are usually flat, and the edges of the upper and lower surface plates and the outer peripheral frame are usually provided. And the contact point with the outside becomes a straight line, and there is a possibility that the foamable resin stock solution and the foam may leak from this portion. Therefore, it is necessary to use a sealing material for preventing leakage, and an outer frame holding mold is disposed outside the outer frame. Thus, it was necessary to prevent deformation of the outer peripheral frame. Further, in general, there are many cases where the material is changed between a front plate that is generally noticeable and requires a high-grade finish and a back plate that is relatively thin in such a requirement, or the thickness is changed even with the same material. However, in the case of using different types of surface plates having different expansion coefficients for the upper and lower surface plates, or in the case of the same material having different thicknesses, a sandwich structure using a rigid polyurethane foam or the like as a core material using them. When the foamed heat insulating board was molded, as the temperature returned to normal temperature after molding, there were many occurrences of warpage due to a bimetal phenomenon due to a difference in rigidity between the front and back of the composite of the surface plate and the foam surface, a difference in linear expansion coefficient, and the like.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a closed injection molding method for producing a foamed heat insulating board having a sandwich structure by injecting a foamable resin stock solution into a space formed by upper and lower surface materials and an outer peripheral frame. Provide a method of manufacturing a foam insulation board using an open injection method without using a method, and at that time, prevent the occurrence of deformation such as warpage without using a new sealing member or a peripheral frame holding mold separately. To provide a method for producing a foamed heat insulating board.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies on a method for manufacturing a foamed heat insulating plate, and as a result, as shown in FIG. After assembling a temporary assembly in which upper portions are provided with flanges 5a, 6a and lower surface plates 5, 6 and an outer peripheral frame 7, the upper die 3 is closed once, and the upper surface plate 5 is sucked to the upper die 3. The upper mold 3 is opened to separate the foaming resin stock solution into the space formed by the lower surface plate 6 and the outer peripheral frame 7 remaining in the lower mold, thereby enabling the foamable resin stock solution to be injected in an open manner. Injection head 8
Injection can be performed linearly to reduce the amount of undiluted solution by uniforming the foam density, preventing surface swelling and other deformation due to the increase in local foaming pressure, processing injection holes, reducing post-processing, and reducing sealing materials. It was found that the need for an outer frame holding mold was achieved, and the present invention was completed.

That is, according to the present invention, the outer peripheral frame 7 is inserted between the upper surface plate 5 and the lower surface plate 6 which are arranged in parallel at regular intervals, and the upper and lower surface plates 5 and 6 are connected to the outer peripheral frame. 7 are integrally fixed to form a closed space, and a foamable resin stock solution is injected into the closed space and filled with foam to manufacture a foamed heat insulating board. The upper surface provided with the bending flanges 5a and 6a on the edge, and the lower surface plate is used.
After assembling the temporary assembly in which the lower surface plate and the outer peripheral frame are combined into a foaming mold including the lower die 1 and the upper die 3, the upper surface plate 5 is moved to the upper die 3.
A foaming heat insulating plate that adsorbs and separates by a suction member provided in the lower mold 1, for example, and is separated, and the foaming resin stock solution 9 is opened and injected into a space formed by the lower surface plate 6 and the outer peripheral frame 7 remaining in the lower mold 1. In this case, the upper mold 3 is a method of manufacturing a foamed heat insulating board using a foam mold in which one end is detachably connected to the lower mold 1 by, for example, a hinge 2 so that the upper mold 3 can be connected to the lower mold 1 by heating. This is a method for producing a foamed heat insulating plate in which the upper and lower dies 3 and 1 provide a temperature difference between the preheating temperatures of the upper surface plate 5 and the lower surface plate 6 by means of upper and lower dies 3 and 1. Is a method for manufacturing a foamed heat insulating board composed of a metal plate, and a method for manufacturing a foamed heat insulating board in which the foamable resin stock solution is a hard foamed polyurethane stock solution.

As shown in FIG. 1, the open injection method is a method in which a foamable resin stock solution is injected into a space formed by a lower surface plate and an outer peripheral frame after being incorporated in a foaming mold. This is a method in which the resin liquid is injected into the open space by opening the upper part, and it is not necessary to provide an injection hole, and the injection head 8 can be freely moved back and forth and left and right while being injected. As a result, it is possible to uniformly inject into the surroundings of the space in a short time, and it is possible to manufacture a homogeneous foam insulation board.

Next, the present invention will be described in more detail. The foaming mold according to the present invention is a foaming mold in which a lower mold 1 and an upper mold 3 are joined at one end thereof with a joining member, such as a hinge 2, which allows the upper mold to close and open. The upper and lower dies press the surface plate,
The upper and lower surface plates are not separated by the foaming pressure, and the outer peripheral frame 7 is not separated.
Any material may be used as long as it is fixed to, but is usually formed of a metal plate and can be heated and cooled inside, for example,
A water channel into which hot and cold water can flow, an electric heater, and the like are provided, and the upper and lower surface plates are preheated to an appropriate temperature, preferably in the range of 40 to 60 ° C., before injecting the foamable resin stock solution. The upper die 3 is provided with a suction member 4 for detachably holding the upper surface plate, and examples of the suction member include an electromagnetic holder and a vacuum suction holder. When the upper surface plate is made of a non-ferrous metal, plastic, gypsum board or the like, a vacuum suction holder is used. In addition, the suction member 4 can be used not only for opening and closing the upper surface plate, but also for releasing the finished product after molding.

The material constituting the upper and lower surface plates 5, 6 and the outer peripheral frame 7 may be any material as long as it has sufficient strength and workability, such as a metal plate, a hard plastic plate, an FRP plate, a gypsum board, Plywood and the like are preferred, preferably a metal plate, particularly preferably a steel plate including a painted steel plate, and most preferably a stainless steel plate. The thickness of the upper surface plate 5, the lower surface plate 6, and the outer peripheral frame 7 may be appropriately designed according to the material.
The range is 5 to 1.5 mm, preferably 0.1 to 0.7 mm, and more preferably 0.2 to 0.5 mm. Also,
The upper and lower surface plates 5 and 6 are preferably provided with bent flanges 5a and 6a at their edges in advance, and the edges are tightly engaged with the outer portion of the outer peripheral frame 7 so that the use of a side template is possible. It eliminates or prevents deformation of the outer peripheral frame due to foaming pressure. The width of the flange varies depending on the thickness of the foam insulating plate to be manufactured, but is in the range of 2 to 15 mm, preferably 3 to 8 mm.

Further, the upper and lower dies may be usually stencils,
These mold plates are provided with a temperature control water channel through which temperature control water flows in and out via a temperature control water connection port from a separately provided temperature control water supply device for adjusting the foaming molding temperature in advance. Generally, the upper and lower molds are used at the same temperature, but preferably,
Temperature-regulated water from a temperature-regulated water supply device provided with a separate temperature difference flows into and out of the lower molds, and a temperature difference is given to the preheating temperature of the foaming mold. The temperature difference is determined by the degree of warpage of the obtained foamed heat insulating board, and is a difference of 5 to 20 ° C, preferably a difference of 8 to 12 ° C. The shape of the outer peripheral frame may be a groove shape, a convex shape, a flat plate shape, or a wavy shape, but it is preferable that the finished frame be a groove shape used for butt joining. The shape is preferable also in improving the rigidity of the outer peripheral frame. As the foamable resin stock solution, a stock solution made of any resin may be used as long as it can form a foamed structure exhibiting sufficient heat insulating properties and rigidity.
Stock solutions of hard polyurethane, soft polyurethane, phenolic resin, urea resin and the like may be used, and hard polyurethane stock solution is particularly preferable.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a foamed heat insulating board according to the present invention. FIG. 1 is a sectional view showing an example of the production of a foamed heat insulating board according to the present invention. A foaming mold is prepared by joining an upper mold 3 via a hinge 2 to a lower mold 1 composed of a flat plate and a frame. The upper die 3 is provided with an electromagnetic holder 4 for attracting the upper surface plate 5. The electromagnetic holder is φ60mm (max.
100N: SS40 × 10mm thickness when adsorbing on the entire surface of the test piece)
Within 150mm from the edge of the upper surface plate flange, pitch 40
It was arranged within 0 mm. 0.30mm thickness × 900mm width × 1800m length in a foaming mold with the upper mold 3 opened
upper surface plate 5 made of stainless steel plate having a thickness of 0.25 m and a thickness of 0.25
A temporary assembly in which a lower surface plate 6 made of a coated steel plate having the same size of 1 mm and an outer peripheral frame 7 made of a stainless steel plate having a plate thickness of 0.6 mm is assembled. At that time, on the upper and lower surface plate,
A surface plate provided with flanges 5a and 6a having a width of 5 mm at its edge was used.

Next, the upper mold 3 is closed and brought into close contact with the upper surface plate 5, and electricity is supplied to the electromagnetic holder 4 so that the upper surface plate 3 is attracted to the upper surface plate 3. At this time, the upper mold 3 and the lower mold 1 were previously adjusted to a temperature of 50 ° C. which was 10 ° C. higher than the lower mold temperature of 40 ° C. by a temperature regulating water supply device (not shown). That is, a temperature difference of 10 ° C. was provided between the upper mold and the lower mold. Thereafter, the upper die 3 is opened with the upper surface plate 5 being adsorbed thereto, and an upper open space is formed by the lower surface plate and the outer peripheral frame.
Thus, the injection head is uniformly moved into the space while moving the injection head back and forth and left and right. Immediately after the injection, the upper mold 3 is closed, and the foam is filled and hardened as it is. When the molding is performed, the electricity is released, the suction is stopped, the upper mold is opened, and the foam heat insulating plate is removed to form a 25 mm thick foam. An insulating plate was obtained. The pressure during foam molding at that time was 0.3 kgf / cm ² .

According to this means, since the pre-assembled upper surface plate is sucked, opened, and then closed, the upper surface plate can be disposed in its original position without any deviation. However, when removing the mold, if the upper mold is opened while being energized and adsorbed, the foamed heat insulating plate is lifted while being adsorbed, and the mold can be easily removed. The obtained foam insulation board, urethane foam leakage from the joint of the upper and lower surface plate and the outer peripheral frame,
Also, there was no outward deformation of the outer peripheral frame and no local irregularities on the surface plate. Further, the foam molded plate was allowed to stand at room temperature (20 ° C.) for 12 hours, and then the warpage of the plate surface was measured. The results are shown in Table 1. As a result, it has been found that the amount of warpage of the plate can be reduced by providing a preheating temperature difference between the upper and lower mold surfaces, that is, the upper and lower surface plates.

[0015]

[Table 1]

[0016]

As described above, in the method for producing a foamed heat insulating board of the present invention, the foamable resin stock solution can be injected by an open injection method, and the amount of the stock solution can be reduced by making the foam density uniform. Prevents deformation of the surface due to non-uniformity, reduction of injection hole processing and post-treatment, etc., and also prevents foam leakage, deformation of the outer frame, etc. Could be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional example.

FIG. 3 is a cross-sectional view of an embodiment in which a temperature adjusting device is provided in upper and lower dies.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower die 1a Lower die temperature control water channel 1b Lower die temperature control water connection port 2 Hinge 3 Upper die 3a Upper die temperature control water passage 3b Upper die temperature control water connection port 4 Electromagnetic holder 5 Upper surface plate 5a Flange 5b Injection hole 6 Lower Surface plate 6a Flange 7 Outer frame 8 Injection head 9 Rigid polyurethane foam stock solution

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29K 75:00 105: 04

Claims (8)

[Claims] 1. An outer peripheral frame 7 is inserted between an upper surface plate 5 and a lower surface plate 6 which are arranged in parallel at regular intervals, and the upper and lower surface plates 5, 6 and the outer peripheral frame 7 are integrated. To form a closed space, and inject a foamable resin stock solution into this closed space, and perform foam filling to produce a foamed heat insulating board.
A temporary assembly in which bent flanges 5a, 6a are provided at the edges of the lower surface plates 5, 6 and the lower surface plate is used, and the upper and lower surface plates and the outer peripheral frame are combined into a lower die 1 and an upper die 3 After being assembled into a foaming mold composed of the following, the upper surface plate 5 is adsorbed and separated by an adsorption member provided on the upper die 3, and is constituted by the lower surface plate 6 and the outer peripheral frame 7 remaining on the lower die 1. A method for producing a foamed heat insulating board, characterized by openly injecting a foamable resin stock solution 9 into a space. 2. The method according to claim 1, wherein the upper mold 3 is a foam mold in which the upper mold 3 is connected to one end of the lower mold 1 so as to be detachable and connectable. 3. The method according to claim 2, wherein the connection is made by a hinge. 4. The method according to claim 1, wherein the attraction member is an electromagnetic holder. 5. The foam insulation board according to claim 1, wherein a temperature difference is previously provided between the upper and lower dies 3 and 1 for the preheating temperature of the upper surface plate 5 and the lower surface plate 6. Manufacturing method. 6. The method according to claim 5, wherein the heating of the upper and lower dies 3 and 1 is performed in temperature control channels provided in each of the dies. 7. The method according to claim 1, wherein the upper and lower surface plates 5, 6 and the outer peripheral frame 7 are made of a metal plate. 8. The method for producing a foamed heat insulating board according to claim 1, wherein the foamable resin stock solution is a hard foamed polyurethane stock solution.