JP2008230223A - Manufacturing method of foamed resin laminated board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a foamed resin laminated board capable of applying a heating method using an far-infrared ray heating as a heating method for a not-yet-foamed layer between a hard layer and another hard layer, on manufacturing a foamed resin laminated board with a foaming resin layer between the hard layer and the hard layer and capable of foaming the foamable resin described above by the far-infrared ray heating. <P>SOLUTION: (1) The manufacturing method comprises preparing a laminated board 20 with a foamable resin layer in a state not yet foamed between the hard layers, bringing a far-infrared absorbing and heat conducting layer 21 and 22 with far-infrared ray absorbing and conductive properties by contacting 21 and 22 into contact with the surface of the hard layer on the one side or both sides of the laminated board 20 and then forming the foaming resin layer by carrying out the far-infrared ray heating to make the foamable resin layer described before. (2) In the manufacturing method of the foamable resin laminated board described before, a weight of the far-infrared absorbing and heat conducting layer 21 is 0.1-10 mg/mm<SP>2</SP>. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention belongs to a technical field related to a method for manufacturing a foamed resin laminate, and more specifically, to a technical field related to a method for manufacturing a foamed resin laminate having a foamed resin layer between a hard layer and a hard layer. It belongs to.

  In JP-A-5-38776, an unfoamable foamable resin is applied to a metal plate and heated in a thermostatic bath to foam the foamable resin to form a foamed resin layer. It is described to obtain a composite insulation panel.

  In JP-A-5-293918, a paste of a thermoplastic resin containing a foaming agent is applied on a base sheet and heated to obtain a cosmetic sheet, which is laminated on a metal plate to obtain a laminate. The laminated plate is heated in an oven to foam the thermoplastic resin to form a foamed resin layer, thereby obtaining a decorative metal plate.

In JP-A-2004-42649, a foamable resin layer is prepared by laminating an unfoamable foamable resin that is foamed at a foaming temperature by heating and a hard plate, and heating the foamed resin to foam the foamable resin. In this way, it is described that a foamed resin laminated soundproof board is obtained.
JP-A-5-38776 JP-A-5-293918 JP 2004-42649 A

  In the method described in the publication, a laminate having an unfoamed foamable resin on a metal plate is heated in a thermostatic bath or oven to foam the thermoplastic resin to form a foamed resin layer. . Thus, when heating with a thermostat or oven, it takes time, and the foamed state is likely to vary due to the distribution of the heating atmosphere. When heated by far-infrared heating, the required heating time can be shortened, and variations in the foamed state are less likely to occur. That is, in order to shorten the required heating time (foaming time) and uniformly foam, it is considered preferable to apply a heating method by far-infrared heating as a heating method for foaming.

  In the case of a laminate having an unfoamed foamable resin on such a metal plate, it is considered that the foamable resin can be foamed by far-infrared heating because the resin has a moderate heat ray absorption rate. . However, in the case of a laminated plate having an unfoamed foamable resin layer between a metal plate such as an aluminum plate and the metal plate, the heat ray absorptance of the surface is extremely small. It is difficult to foam.

  In addition, in the case of such a laminated board, it can be foamed when heated in a thermostatic bath or oven, but the foamed state is likely to vary depending on the distribution of the heating atmosphere.

  The present invention has been made in view of such circumstances. The purpose of the present invention is to manufacture a foamed resin laminate having a foamed resin layer between the hard layer and the hard layer. A heating method by far-infrared heating can be applied as a heating method for an unfoamed foamable resin layer in between, and a method for producing a foamed resin laminate capable of foaming the foamable resin by this far-infrared heating is provided. It is something to try.

  As a result of intensive studies to achieve the above object, the present inventors have completed the present invention. According to the present invention, the above object can be achieved.

  The present invention, which has been completed in this way and has achieved the above object, relates to a method for producing a foamed resin laminate, and a method for producing a foamed resin laminate according to claims 1 to 7 (inventions 1 to 7). This is a method for producing a foamed resin laminate, and has the following configuration.

  That is, the method for producing a foamed resin laminate according to claim 1 is a method for producing a foamed resin laminate having a foamed resin layer between a hard layer and a hard layer, and the method is provided between the hard layer and the hard layer. A laminated board having a foamable resin layer in an unfoamed state is prepared, and a far-infrared absorbing heat transfer layer having a far-infrared absorbing property and a heat transferring property is provided in contact with the surface of one or both hard layers of the laminated board. A method for producing a foamed resin laminate, wherein the foamable resin is foamed by far infrared heating to form a foamed resin layer [first invention].

  The method for producing a foamed resin laminate according to claim 2, wherein the far-infrared absorbing heat transfer layer is made of a resin sheet, a rubber sheet, a far-infrared absorbing metal plate or a composite plate thereof. It is a manufacturing method of a laminated board [2nd invention].

  The method for producing a foamed resin laminate according to claim 3 is the method for producing a foamed resin laminate according to claim 1 or 2, wherein the hard layer is made of an aluminum plate or a steel plate [third invention].

Method for manufacturing a foamed resin laminate according to claim 4 wherein the method for manufacturing a foamed resin laminate according to any one of claims 1 to 3 wt of the far-infrared-absorbing heat transfer layer is 0.1 to 10 mg / mm ² [Fourth Invention] 5. The method for producing a foamed resin laminate according to claim 5, wherein the far-infrared absorption heat transfer layer is charged before contacting the hard layer and then brought into contact with the hard layer. [5th invention].

  The manufacturing method of the foaming resin laminated board of Claim 6 removes the said far-infrared absorptive heat-transfer layer, after performing far-infrared heating and foaming the said foamable resin to make a foamed resin layer. 5. A method for producing a foamed resin laminate according to any one of 5 [6th invention].

  The foamed resin laminate according to any one of claims 1 to 6, wherein the foamed resin laminate has a reflectance of 0.85 to 1.0 at a wavelength of 4500 nm on the surface of the hard layer. [7th invention].

  According to the method for producing a foamed resin laminate according to the present invention, when producing a foamed resin laminate having a foamed resin layer between the hard layer and the hard layer, an unfoamed state between the hard layer and the hard layer is present. As the heating method of the foamable resin layer, a heating method by far infrared heating can be applied, and the foamable resin can be foamed by this far infrared heating. That is, according to the present invention, even if the hard layer surface is an aluminum plate having an extremely low far-infrared absorptivity, it can be suitably foamed, and the far-infrared absorbing heat transfer layer can be obtained after heating and foaming the foamed resin laminate. Since it can be detachably provided, the surface of the foamed resin laminate can be easily and easily returned to a state where the infrared absorption rate is extremely small. For this reason, for example, even when the foamed resin laminate is used as a member near a heat source such as an engine exhaust pipe of an automobile, the foamed resin laminate of the present invention can have an extremely low infrared absorptivity and radiant heat from the heat source. Heat deterioration due to can be suppressed.

  As described above, the method for producing a foamed resin laminate according to the present invention is a method for producing a foamed resin laminate having a foamed resin layer between a hard layer and a hard layer. A laminate having an unfoamed foamable resin layer in between is produced, and a far-infrared absorbing heat transfer layer having far-infrared absorption and heat transfer is brought into contact with the surface of one or both hard layers of the laminate. And a far-infrared heating is performed to foam the foamable resin to form a foamed resin layer.

  The far-infrared absorption heat transfer layer has far-infrared absorption and heat transfer, and is in contact with the surface of the hard layer of the laminate. Therefore, during the far-infrared heating, the far-infrared absorption heat transfer layer absorbs far-infrared rays, transfers heat to the hard layer, and transfers heat from the hard layer to the unfoamed foamable resin layer, thereby enabling foaming. The resin can be heated to foam. When there is a layer other than the above between the hard layer and the unfoamed foamable resin layer, heat is transferred to the unfoamable foamable resin layer through this layer.

  Therefore, according to the method for producing a foamed resin laminate according to the present invention, in the production of a foamed resin laminate having a foamed resin layer between the hard layer and the hard layer, an unexposed portion between the hard layer and the hard layer is used. As a heating method of the foamable resin layer in the foamed state, a heating method by far infrared heating can be applied, and the foamable resin can be foamed by this far infrared heating.

  The far infrared absorbing heat transfer layer is removed after foaming by far infrared heating. Thereby, a foamed resin laminate is obtained. When foaming by far-infrared heating, the far-infrared absorbing heat transfer layer only needs to be in contact with the surface of the hard layer of the laminate so that heat can be transferred, and it is necessary to have a strong adhesion such as painting. Absent. If the far-infrared absorbing heat transfer layer is not firmly attached to the hard layer surface of the laminate and is in contact with the hard layer surface of the laminate so that heat can be transferred, it is easy after foaming by far-infrared heating. For this reason, a foamed resin laminate is obtained in which the substrate of the hard layer is utilized as it is.

  In the case of the method for producing a foamed resin laminate according to the present invention, when compared with a case where a laminate having an unfoamable foamable resin layer between a hard layer and a hard layer is heated in a thermostatic bath or oven, Since the heat absorption + heat transfer effect is high, the required heating time (foaming time) can be shortened, and the variation in temperature is small and the variation in the foamed state is difficult to occur.

  In the method for producing a foamed resin laminate according to the present invention, the far infrared absorption heat transfer layer is a layer having far infrared absorption and heat transfer. Examples of the far infrared absorbing heat transfer layer include a resin sheet, a rubber sheet, a far infrared absorbing metal plate, or a composite plate thereof [second invention]. Examples of the far-infrared absorbing heat transfer layer include a heat-resistant rubber sheet and a coated aluminum plate (for example, black), and in order to give the far-infrared absorbing heat transfer layer both adhesive and durable. The thing laminated | stacked together can be mentioned. Furthermore, a rubber sheet reinforced with reinforcing fibers can also be mentioned. More specifically, as the resin-based far-infrared absorbing heat transfer layer, heat-resistant materials such as fluorine-based, acrylic-based, silicon-based heat-resistant polymer sheets, resins having a melting point higher than the foaming temperature, heat-resistant masking tape, etc. In addition, there may be mentioned those having adhesiveness in order to improve the adhesion. Examples of the metal-based far-infrared absorbing heat transfer layer include an aluminum plate, a steel plate, a copper plate and the like roughened by coating with a heat-resistant paint, blasting, anodizing, or the like. Moreover, in order to give rigidity and adhesiveness, what has the heat-resistant polymer layer on the metal surface can also be mentioned. The far-infrared absorption heat transfer layer is more excellent in far-infrared absorptivity and heat transfer, but the level is not particularly limited. Any material having far infrared absorptivity and heat conductivity is sufficient.

  In the method for producing a foamed resin laminate according to the present invention, the hard layer is not limited to a metal plate, and a resin plate can be used. Examples of the metal plate include an aluminum plate and a steel plate [third invention]. The aluminum plate is not limited to a pure aluminum plate, and includes various aluminum alloy plates, and the steel plate includes stainless steel, plated steel plate and the like. In addition, when a hard layer is a metal plate, the foamed resin laminated plate in the manufacturing method of the foamed resin laminated plate which concerns on this invention can also be called a foamed resin laminated metal plate.

When foaming by far-infrared heating, the foamable resin between the hard layer and the hard layer is softened, so if the far-infrared absorption heat transfer layer is too heavy, the foaming is inhibited and the expansion ratio is reduced. There is a risk of destroying the bubbles. For this reason, it is desirable that the weight does not hinder foaming. On the other hand, even if the weight is too light, the adhesion to the hard layer surface is lowered, and the heat transfer amount from the far-infrared absorbing heat transfer layer to the hard layer is reduced. From this point, it is desirable that the weight of the far-infrared absorbing heat transfer layer is 0.1 to 10 mg / mm ² [fourth invention]. In this case, foaming can be performed better without hindering foaming, and the adhesion to the hard layer surface is good, so that heat transfer from the far-infrared absorbing heat transfer layer to the hard layer is better. It can be carried out.

  In order to efficiently transfer heat from the far-infrared absorbing heat transfer layer to the hard layer, it is better to improve the adhesion between the far-infrared absorbing heat transfer layer and the hard layer. Therefore, the far-infrared absorbing heat transfer layer may be attached to the hard layer before producing a laminate having an unfoamed foamable resin layer between the hard layer and the hard layer. The far-infrared absorbing heat transfer layer may be attached to the hard layer simultaneously with the production.

If the far-infrared absorbing heat transfer layer is charged before contacting the hard layer, and then contacted with the hard layer, the adhesion between the far-infrared absorbing heat transfer layer and the hard layer increases, and in turn the foaming time can be shortened. [Fifth Invention]. Further, after heating and foaming, the far-infrared absorbing heat transfer layer can be easily removed, and the surface of the hard layer is not contaminated, and a foamed resin laminate using the base of the hard layer as it is can be obtained. In this way, if the far-infrared absorbing heat transfer layer is charged, that is, a method using static electricity, the far-infrared absorbing heat transfer layer may be light, and the weight of the far-infrared absorbing heat transfer layer is 0.1. mg / mm need not be greater than or equal to ^2. However, since the far infrared absorption heat transfer layer needs to be charged in the above method, the far infrared absorption heat transfer layer needs to have a sufficiently high electric resistance value. When a metal is used for the far-infrared absorption heat transfer layer, or even if it is a resin, a pigment that lowers the electric resistance value such as carbon is added and the electric resistance value is low, the above method cannot be used.

  It is also possible to employ a method in which the far-infrared absorbing heat transfer layer is provided only at a necessary location to partially promote foaming. Moreover, a far-infrared absorption heat-transfer layer may be provided in both the hard layers of a laminated board, and a far-infrared absorption heat-transfer layer may be provided only in one hard layer. When the far infrared absorption heat transfer layer is provided only on one of the hard layers, the far infrared heating from one side may be performed. Far-infrared heating refers to the use of an electromagnetic wave having a wavelength of 4000 nm or more in a narrow sense, but is not limited to this, and refers to heating in general using an electromagnetic wave having a relatively long wavelength among infrared rays.

  The unfoamable foamable resin contains a matrix resin and a foamable component (foaming agent). The matrix resin includes polyolefin, polystyrene, polyurethane, and the like, but also includes polyester, EVA, and PVC. Examples of the polyolefin resin include polyethylene resin, polyolefin resin, EPR, and EPDM. Examples of polystyrene resins include polystyrene resins, thermoplastic elastomers, ABS resins, and AS resins. These resins are thermoplastic resins and have the property of being softened by heating and having high plasticity. The foamable resin in an unfoamed state can be more specifically referred to as an unfoamable foamable resin that is foamed at the foaming temperature by heating.

  As the foamable component (foaming agent), either an organic foaming agent or an inorganic foaming agent can be used. As the organic foaming agent, for example, an azo compound, a nitroso compound, a sulfonyl hydrazide compound, and other compounds can be used. Specifically, azodicarbonamide, barium azodicarboxylate, azobisisobutyronitrile, N, N'-dinitrosopentamethylenetetramine, p-toluenesulfonyl hydrazide, p, p'-oxybis (benzenesulfonyl hydrazide), hydrazodicarbonamide, diphenylsulfone-3,3-disulfonyl hydrazide, p-toluenesulfonyl semicarbazide , Trihydrazinotriazine, biurea and the like. Examples of the inorganic foaming agent include sodium hydrogen carbonate and zinc carbonate, and further thermally expandable microcapsules. Among these foamable components, those that foam by heating to 120 ° C. or higher, more preferably 150 ° C. or higher are preferable. For the matrix polymer, a person having a melting point at a temperature sufficiently higher than the use environment temperature of the laminated board is selected, but it is necessary to set the foaming temperature of the foaming agent to a temperature about 20 ° C. higher than the melting point. . In addition, the said foamable component may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the method for producing a foamed resin laminate according to the present invention, the foamed resin laminate having a foamed resin layer between the hard layer and the hard layer is a foamed resin having only the foamed resin layer between the hard layer and the hard layer. It is not limited to a laminated board, The foamed resin laminated board which has layers other than a foamed resin layer and this foamed resin layer between a hard layer and a hard layer is also contained. In the case of a foamed resin laminate having a layer other than the latter foamed resin layer, the layer other than the foamed resin layer is not limited to a single layer, including cases of two or more layers, and the foamed resin layer is not limited to a single layer. Also, the case of two or more layers is included. Examples of the layer other than the foamed resin layer include an adhesive film for thermally fusing the hard layer and the foamed resin layer.

  In the method for producing a foamed resin laminate according to the present invention, after the far infrared heating is performed to foam the foamable resin to form a foamed resin layer, the far infrared absorbing heat transfer layer can be removed.

  Moreover, since the manufacturing method of the foamed resin laminated board which concerns on this invention can remove the said heat-transfer layer from a foamed resin laminated board easily after heat foaming, the reflectance of a hard layer is 0.85-1. It can also be applied to those that are extremely difficult to heat by far infrared heating, such as 0. What has such a reflectance is a foamed resin laminate that is easy to obtain the effects of the present invention because it can be used for a member near the heat source after removing the heat transfer layer.

  Examples of the present invention and comparative examples will be described below. The present invention is not limited to this embodiment, and can be implemented with appropriate modifications within a range that can be adapted to the gist of the present invention, all of which are within the technical scope of the present invention. include.

[Example 1]
A method for producing a foamed resin laminate according to Example 1 is shown in FIG. As can be seen from FIG. 1, a foamed resin laminate was produced by three types of production methods [(A), (B), (C)].

  The manufacturing method (A) is to produce a laminated plate 4 having an unfoamed foamable resin layer 3 between an aluminum plate (corresponding to a kind of hard layer) 1 and the aluminum plate 2, and In this method, the foamable resin is foamed by heating with far infrared rays. In this case, it takes a very long time to reach the foaming temperature.

  In the production method (B), a far-infrared absorbing heat transfer layer 5 having a far-infrared absorbing property and a heat-transmitting property by applying a paint to the surfaces of both the laminated plates 4 (the aluminum plate 1 and the aluminum plate 2) as described above. After forming, the far-infrared heating is performed to foam the foamable resin. In this case, the time to reach the foaming temperature is shorter than in the case of the production method (A), and the variation in temperature is small and the foamed state is less uneven. However, in the case where the laminated plate is used near the heat source, it is necessary to remove the paint after foaming. If the paint is removed, the luster of the aluminum substrate is lost. In addition, a process of applying a paint or removing a paint is necessary, and the cost increases due to these processes. The number 6 indicates a foamed resin layer.

  In the production method (C), the black heat-resistant rubbers 7 and 8 are provided as the far-infrared absorbing heat transfer layers on the surfaces of both the laminated plates 4 (the aluminum plate 1 and the aluminum plate 2) as described above, In this method, the foamable resin is foamed by performing far infrared heating. In this case, the time to reach the foaming temperature is shorter than in the case of the production method (A), and the variation in temperature is small and the foamed state is less uneven. Further, when the black heat-resistant rubber is removed after foaming, the aluminum substrate has gloss, and the gloss of the aluminum substrate as in the production method (B) is not lost. The number 9 indicates a foamed resin layer.

[Example 2]
A method for producing a foamed resin laminate according to Example 2 is shown in FIG. As can be seen from FIG. 2, a laminated plate 4 having a foamable resin layer 3 in an unfoamed state between the aluminum plate 1 and the aluminum plate 2 is produced, and at the same time, the surfaces of the aluminum plate 1 and the aluminum plate 2 are distant. Infrared absorbing heat transfer layers 10 and 11 were affixed with an adhesive tape, and then far infrared heating was performed to foam the foamable resin. In this case, as in the case of the production method (C) of Example 1, the time until the foaming temperature is reached is short, the temperature variation is small, and the unevenness of the foamed state is small. Further, after foaming, the far-infrared absorbing heat transfer layers 10 and 11 can be easily removed. If this is removed, the gloss of the aluminum base is lost, and the gloss of the aluminum base as in the manufacturing method (B) is lost. There is no end to it. Reference numeral 12 denotes a foamed resin layer. The heat transfer layer in the figure is a far infrared absorption heat transfer layer.

[Example 3]
After producing a laminate having an unfoamed foamable resin layer between the hard layer and the hard layer, and providing a far-infrared absorbing heat transfer layer in contact with the surface of both hard layers of the laminate Then, far-infrared heating was performed to foam the foamable resin to form a foamed resin layer, and then the far-infrared absorbing heat transfer layer was removed to obtain a foamed resin laminate.

  At this time, an aluminum plate (1200-O, t0.15) is used as the hard plate, a normal-pressure secondary expanded polypropylene (sheet-like) is used as the foamable resin layer in an unfoamed state, and a fluorine is used as the far-infrared absorbing heat transfer layer A black heat-resistant rubber (t0.3), a white heat-resistant rubber, or a black painted aluminum plate (t0.15) was used. The hard plate and the foamable resin layer were bonded with a heat-sealing film.

  Far-infrared heating was performed as follows. As shown in FIG. 3, the upper surface of the laminated board 20 which has the layer of foamable resin (sheet | seat of a normal pressure secondary foaming polypropylene) of a non-foamed state between a hard layer (aluminum board) and a hard layer (aluminum board). In addition, far-infrared ceramic heaters (manufactured by Sakaguchi Electric Heat Co., Ltd.) 23 and 24 were provided above and below what was provided with the far-infrared absorption heat transfer layers 21 and 22 in contact with the lower surface, and far-infrared heating was performed. The distance between the far-infrared ceramic plate of the far-infrared ceramic heater and the object to be heated is as shown in FIG.

  On the other hand, a laminated board similar to the above was prepared, and the far-infrared heat transfer layer was not provided on any side of the laminated board, and far-infrared heating was performed by the same method as described above to obtain the foamable resin. Foaming was performed to form a foamed resin layer to obtain a foamed resin laminate.

  When far-infrared heating is performed in a state where this far-infrared absorbing heat transfer layer is not provided, it takes a very long time for foaming, and the foamed state is highly uneven. On the other hand, when far-infrared heating was performed with the far-infrared absorbing heat transfer layer provided, foaming was possible in a short time, and foaming was uniform and the foamed state was less uneven.

[Example 4]
As shown in FIG. 4, a thermocouple 27 is attached between two A4 size aluminum plates (t0.15) (numbers 25 and 26), and the upper surface of the aluminum plate 25 and the aluminum plate 26 are attached. A far-infrared absorption heat transfer layer was provided in contact with the lower surface, and far-infrared heating was performed to examine the change in temperature of the aluminum plate over time (average value and variation). At this time, the far-infrared heating was performed using the same far-infrared ceramic heater as in Example 3. The distance between the far infrared ceramic plate 23 of the far infrared ceramic heater and the upper surface of the aluminum plate 25 and the distance between the far infrared ceramic plate 24 and the lower surface of the aluminum plate 26 were both 50 mm. As the far-infrared absorbing heat transfer layer, a black heat-resistant rubber (t0.3), white, or black painted aluminum plate (t0.15) was used.

  Also, in the same manner as described above, the thermocouple 27 is sandwiched between two A4 size aluminum plates, and far infrared heating is performed in the same manner as described above without providing a far infrared absorbing heat transfer layer. The temperature change of the aluminum plate over time (average value and variation) was examined.

  FIG. 5 shows the measurement results of the change in temperature of the aluminum plate with time. (A) of FIG. 5 shows the change with time of the average value of the temperature at each position. (B) of FIG. 5 shows the change with time of the difference (variation) between the maximum value and the minimum value of the temperature at each position.

  As can be seen from FIGS. 5A and 5B, the temperature of the aluminum plate is higher when the former far infrared absorbing heat transfer layer is provided than when the latter far infrared absorbing heat transfer layer is not provided. The rate of increase in temperature is extremely fast, the time from the start of far-infrared heating to 230 ° C. (corresponding to the decomposition temperature of the blowing agent) is remarkably short, and the temperature variation at 230 ° C. is extremely high. small.

  In the case where the former far-infrared absorbing heat transfer layer is provided, there is almost no difference in the degree of temperature variation when the temperature of the aluminum plate rises to 230 ° C. depending on the type of the far-infrared absorbing heat transfer layer. Absent.

[Example 5]
As the far-infrared absorbing heat transfer layer, a Teflon sheet (t0.1 mm) manufactured by Chuko Kasei Kogyo Co., Ltd. or a charged Teflon sheet was used. (Teflon is a registered trademark. The same shall apply hereinafter.)

  The Teflon sheet was charged using a direct current high voltage generator CH-20 manufactured by SIMCO. At this time, as charging conditions, the voltage was 20 kV, and the distance between the charging bar and the object (Teflon sheet) was 60 mm.

  The far-infrared absorbing heat transfer layer (Teflon sheet or charged Teflon sheet) on the surface of both hard layers of the laminate having an unfoamed foamable resin layer between the hard layer and the hard layer After being provided in contact with each other, far-infrared heating was performed to foam the foamable resin. Then, the time until the time when the foamed layer (0.9 mm) was tripled (2.7 mm) was measured. At this time, far infrared heating was performed using a far infrared ceramic heater. The distance between the far-infrared ceramic plate of the far-infrared ceramic heater and the hard layer surface of the laminate is 100 mm. The voltage of the far-infrared ceramic heater is 250V.

  As a result of the above measurement, when a Teflon sheet (uncharged) is used as the far-infrared absorbing heat transfer layer, the time required for the foamed layer to triple is 8 minutes. When a charged Teflon sheet was used as the heat transfer layer, the time required to triple the foamed layer was 6 minutes 30 seconds, and the foaming time was shortened. This is because when a charged Teflon sheet is used as the far-infrared absorbing heat transfer layer, the adhesion between the far-infrared absorbing heat transfer layer and the hard layer of the laminate increases, and as a result, the far-infrared absorbing heat transfer layer to the hard layer This is because it has become possible to conduct heat efficiently to In either case, after foaming, the far-infrared absorbing heat transfer layer can be easily removed, and the foamed resin laminate is obtained without contaminating the surface of the hard layer and using the substrate of the hard layer as it is. It was.

  According to the method for producing a foamed resin laminate according to the present invention, when producing a foamed resin laminate having a foamed resin layer between the hard layer and the hard layer, an unfoamed state between the hard layer and the hard layer is present. As the heating method of the foamable resin layer, a heating method by far infrared heating can be applied, and the foamable resin can be foamed by this far infrared heating, so that the heating time for foaming is short, The variation in temperature is small, and the variation in the foamed state is difficult to occur. Furthermore, even a hard layer having a high reflectance can be applied, and after heating and foaming, the far infrared absorption heat transfer layer can be easily removed to easily return to the original hard layer having a high reflectance. Therefore, it is useful for producing a foamed resin laminate used near the heat source. Therefore, the method for producing a foamed resin laminate according to the present invention is very useful because it can produce a foamed resin laminate that is efficient and excellent in quality.

5 is a schematic view showing a method for manufacturing a foamed resin laminate according to Example 1. FIG. 6 is a schematic diagram showing a method for manufacturing a foamed resin laminate according to Example 2. FIG. 6 is a schematic diagram illustrating a far infrared heating method according to Example 3. FIG. It is a schematic diagram which shows the thermocouple pinched | interposed between the aluminum plate which concerns on Example 4, and this aluminum plate. It is a figure which shows the time change (average value and dispersion | variation) of the temperature of the aluminum plate which concerns on Example 4, Comprising: (A) of FIG. 4 shows the time change of the average value of the temperature in each measurement position. FIG. 4B shows the change with time in the difference (variation) between the maximum value and the minimum value of the temperature at each measurement position.

Explanation of symbols

1--aluminum plate, 2--aluminum plate, 3--layer of foamable resin in an unfoamed state,
4—Laminated plate having an unfoamed foamable resin layer 3 between the aluminum plate 1 and the aluminum plate 2, 5—Far infrared absorption heat transfer layer, 6—Foamed resin layer, 7—Black Heat-resistant rubber, 8--black heat-resistant rubber, 9--foam resin layer, 10--far infrared absorption heat transfer layer, 11--far infrared absorption heat transfer layer, 12--foam resin layer, 20--hard layer Laminate with unfoamed foamable resin layer between hard layer, 21--far infrared absorbing heat transfer layer, 22--far infrared absorbing heat transfer layer, 23--far infrared ceramic heater, 24- -Far infrared ceramic heater, 25--aluminum plate, 26--aluminum plate, 27--thermocouple.

Claims (7)

  A method for producing a foamed resin laminate having a foamed resin layer between a hard layer and a hard layer, wherein a laminate having an unfoamable foamable resin layer between the hard layer and the hard layer is produced. A far-infrared absorption heat transfer layer having far-infrared absorption and heat transfer is provided in contact with the surface of one or both hard layers of this laminate, and the foamable resin is expanded by foaming the far-infrared heat. A method for producing a foamed resin laminate, characterized by comprising a resin layer.   The method for producing a foamed resin laminate according to claim 1, wherein the far-infrared absorbing heat transfer layer is made of a resin sheet, a rubber sheet, a far-infrared absorbing metal plate, or a composite plate thereof.   The method for producing a foamed resin laminate according to claim 1 or 2, wherein the hard layer is made of an aluminum plate or a steel plate. Method for manufacturing a foamed resin laminate according to any one of claims 1 to 3 wt of the far-infrared-absorbing heat transfer layer is 0.1 ~10mg / mm ^2.   The method for producing a foamed resin laminate according to any one of claims 1 to 4, wherein the far-infrared absorbing heat transfer layer is charged before being brought into contact with the hard layer and then brought into contact with the hard layer.   The method for producing a foamed resin laminate according to any one of claims 1 to 5, wherein after the far-infrared heating is performed to foam the foamable resin to form a foamed resin layer, the far-infrared absorption heat transfer layer is removed. .   The method for producing a foamed resin laminate according to any one of claims 1 to 6, wherein the reflectance of the hard layer surface at a wavelength of 4500 nm is 0.85 to 1.0.