JP2009279922A - Manufacturing process of foaming resin laminated plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing process of a foaming resin laminated plate which can improve the plate-thickness accuracy of a laminated plate after heating and foaming. <P>SOLUTION: This laminated plate is heated in the heating step in order that the temperature of the laminated plate satisfies a formula: T<SB>f</SB>-100°C≤Ts≤T<SB>f</SB>-50°C (T<SB>f</SB>: the decomposition temperature of a foaming agent, Ts: the temperature of the laminated plate) and the temperature difference between the respective parts of the laminated plate satisfies a formula: ΔTs≤30°C (ΔTs: the temperature difference between the respective parts of the laminated plate). Thereafter, the laminated plate is heated and foamed by heating this laminated plate at the decomposition temperature or higher of the foaming agent included in a foamable resin layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a foamed resin laminate comprising at least a hard layer and a foamed resin layer.

  As a technique regarding the manufacturing method of a foamed resin laminated board, there exist some which are described in patent document 1, for example. In the manufacturing method of a foamed resin laminated soundproof board described in Patent Document 1, first, an unfoamable foamable resin and a hard board are laminated and integrated at a temperature lower than the foaming temperature, and the laminated board that is laminated and integrated is pressed. A predetermined shape is obtained. Thereafter, the laminated board having a predetermined shape is heated to form a foamed resin layer inside, and a foamed resin laminated soundproof board having soundproofing properties is obtained. In Patent Document 1, it is said that forming a foamed resin layer by heating a laminated plate to a predetermined shape eliminates restrictions on the shape and construction location of the laminated plate.

JP 2004-42649 A

  However, in the heat foaming in the manufacturing process of the foamed resin laminate, the thickness of the foamed resin laminate is generally not restricted. For this reason, there is a problem that the thickness of the foamed resin laminate after foaming varies, and a desired plate thickness accuracy cannot be obtained. In particular, in the case of heating and foaming by hot air convection heating, simply placing the laminated plate in the furnace causes temperature unevenness depending on how hot air contacts the laminated plate, and it is difficult to obtain a desired thickness accuracy. It was.

  This invention is made | formed in view of the said situation, The objective is to provide the manufacturing method of the foaming resin laminated board which can improve the board | plate thickness precision of the laminated board after heat foaming.

Means and effects for solving the problems

The present invention provides a laminating step in which a non-foamable foamable resin layer and a hard layer are laminated to form a laminated board, and the temperature of the laminated board satisfies the following formula (A) and between the parts of the laminated board And a heating step of heating the laminate to a temperature equal to or higher than the decomposition temperature of the foaming agent contained in the foamable resin layer after heating the laminate so that the temperature difference satisfies the following formula (B): It is a manufacturing method of a resin laminated board.
(Equation 1)
T _f −100 ° C. ≦ Ts ≦ T _f −50 ° C. (A)
T _f : Decomposition temperature of the foaming agent, Ts: Temperature of the laminate (Equation 2)
ΔTs ≦ 30 ℃ (B)
ΔTs: Temperature difference between each part of the laminate

  As a result of intensive studies to achieve the above object, the inventors of the present invention have determined that the temperature of the laminated plate and the temperature difference between each part of the laminated plate are predetermined conditions ((A It was found that by controlling the heating of the laminated plate so as to satisfy the formulas (B) and (B), and then heating and foaming, the thickness accuracy of the laminated plate after heating and foaming can be improved.

  Preferably, the hard layer is made of a metal plate. More preferably, the metal plate is made of an aluminum plate or an aluminum alloy plate. According to this structure, the rigidity and lightness of a foamed resin laminated board can be improved by setting it as the hard layer which consists of an aluminum plate or an aluminum alloy plate.

  More preferably, the matrix resin of the foamable resin layer is made of a polyolefin resin. According to this structure, the uniform foamability of the foamable resin layer can be improved, and the thickness accuracy of the laminate is further improved.

More preferably, after the heating step is performed such that the temperature Ts of the laminate further satisfies the following formula (C), the heating step is performed at a temperature equal to or higher than the decomposition temperature of the foaming agent contained in the foamable resin layer. And the step of heating the laminate. According to this configuration, deformation of the laminate in an unfoamed state can be prevented, and the thickness accuracy of the laminate after heating and foaming can be further improved.
(Equation 3)
Ts ≦ Tm (C)
Tm: deflection temperature under load of unfoamed laminate

It is a perspective view which shows one form of a foamed resin laminated board. It is a top view of the foaming resin laminated board for showing a temperature measurement position. It is a graph which shows the relationship between the temperature difference between each part of a foamed resin laminated board, and the standard deviation of the thickness of the foamed foamed resin layer. It is a flowchart for showing the manufacturing method of the foamed resin laminated board which concerns on one Embodiment of this invention. It is a figure which shows the form and experimental form of the foamed resin laminated board used in experiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The foamed resin laminate obtained by the production method according to the present invention is used as a material for a structure constituting a main body such as a bullet train or an airplane. In addition, this foamed resin laminate can be widely used as a material for building floors, walls, ceilings and the like.

(Configuration of foamed resin laminate)
FIG. 1 is a perspective view showing one embodiment of a foamed resin laminate. Fig.1 (a) is a perspective view of the foamed resin laminated board 1 before foaming (non-foamed state), and FIG.1 (b) is a perspective view of the foamed resin laminated board 1 after foaming.

  As shown in FIG. 1A, the foamed resin laminate 1 before foaming includes an unfoamed foamable resin layer 4a, and two aluminum plates 2 disposed on both sides of the foamable resin layer 4a. Consists of. When the foamable resin layer 4a is heated and foamed, the foamed resin layer 4b is formed, and the foamed resin laminate 1 after foaming shown in FIG.

  The foamed resin laminate 1 includes the foamed resin layer 4b and the two hard layers 2 disposed on both sides of the foamed resin layer 4b. However, the present invention is not limited to such a configuration, and the foamed resin layer 4b A resin layer that does not foam may be further disposed between the hard layer 2 and the hard layer 2, or only one foamed resin layer 4b and one hard layer 2 may be disposed adjacent to each other, or in parallel. Two foamed resin layers 4b may be disposed between the three hard layers 2 disposed. That is, it may be a foamed resin laminate having at least a hard layer and a foamed resin layer.

  The foamable resin layer 4a has a matrix resin and a foaming agent. Examples of the matrix resin include polyolefin resin, polystyrene resin, polyurethane resin, and polyester resin. Examples of the polyolefin resin include polypropylene resin, polyethylene resin, polyolefin resin, EPR, and EPDM. Examples of the polystyrene resin include polystyrene resin, thermoplastic elastomer, ABS resin, and AS resin. These resins are thermoplastic resins and have the property of being softened by heating and having high plasticity.

  Examples of the foaming agent include an organic foaming agent and an inorganic foaming agent. Examples of organic foaming agents include azo compounds, nitroso compounds, sulfonyl hydrazide compounds, and the like. Specifically, azodicarbonamide (ADCA), barium azodicarboxylate, azobisisobutyronitrile, N, N′-dinitroso Examples include pentamethylenetetramine, p-toluenesulfonyl hydrazide, p, p′-oxybis (benzenesulfonyl hydrazide), and the like. Examples of the inorganic foaming agent include sodium hydrogen carbonate, zinc carbonate, and thermally expandable microcapsules. The foaming agent must be selected such that the foaming temperature (decomposition temperature) is about 20 ° C. higher than the melting point of the matrix resin. Moreover, one type of foaming agent may be used alone, or two or more types of foaming agents may be used in combination.

  The hard layer 2 is not limited to the aluminum plate 2, and may be a metal plate such as an aluminum alloy plate, a stainless plate, a plated steel plate, or a resin plate.

  The foamable resin layer 4a and the aluminum plate 2 may be bonded using an adhesive, or may be welded at a temperature lower than the foaming temperature of the foamable resin layer 4a.

  Next, the manufacturing method of the foaming resin laminated board which concerns on one Embodiment of this invention is demonstrated.

(Examination of heating process)
First, it describes about the examination of the heating process in the manufacturing process of a foamed resin laminated board which the present inventors implemented. FIG. 2 is a plan view of the foamed resin laminate 1 for showing a temperature measurement position.

  The foamed resin laminate 1 used in the examination experiment of the heating step is a square plate having a length of 1.0 m and a width of 1.0 m. The foamed resin laminate 1 is obtained by bonding an aluminum plate 2 having a thickness of 0.15 mm to both surfaces of a foamable resin layer 4a having a thickness of 0.9 mm. For the foamable resin layer 4a, a polypropylene resin was used as a matrix resin, and an ADCA foaming agent (decomposition temperature 195 ° C., manufactured by Eiwa Chemical Industry Co., Ltd.) was used as a foaming agent. The final thickness of the foamed resin layer 4b after heat foaming is designed to be 2.7 mm (three times the thickness before foaming).

  As a heating means, a gas heating type continuous heating furnace (furnace length 10 m, furnace width 2.2 m) was used. As shown in FIG. 2, the temperature of the foamed resin laminate 1 was measured at nine locations (points P1 to P9). A thermocouple was directly attached to the surface of the aluminum plate 2 of the foamed resin laminate 1 with Kapton tape, and temperature data was collected with a data logger (manufactured by Graphtec Corporation, midi LOGGER GL200).

  The examination experiment of the heating process was conducted by setting the in-furnace temperature of the gas heating type continuous heating furnace to 200 ° C., setting the feed rate to 0.8 m / min, and placing the foamed resin laminate 1 in the gas heating type continuous heating furnace. The inside was progressing. A direction A shown in FIG. 2 is a traveling direction of the foamed resin laminate 1 in the gas heating type continuous heating furnace.

  FIG. 3 is a graph showing the experimental results, and shows the relationship between the temperature difference between each part of the foamed resin laminate 1 and the standard deviation of the thickness of the foamed foamed resin layer 4b. The vertical axis | shaft of Fig.3 (a) and FIG.3 (b) is a standard deviation (mm) of the thickness (final thickness) of both the foamed resin layers 4b. The horizontal axis of Fig.3 (a) is between each part of the foamed resin laminated board 1 when the average board temperature (temperature) of the foamed resin laminated board 1 is 100 degreeC lower than the decomposition temperature (195 degreeC) of a foaming agent. 3 is a temperature difference (° C.), and the horizontal axis of FIG. 3B represents a temperature difference (° C.) between each part of the foamed resin laminate 1 when the average plate temperature (temperature) of the foamed resin laminate 1 is 195 ° C. ). Here, the average board temperature of the foamed resin laminate 1 refers to the average value of the temperature data measured at the nine temperature measurement positions (points P1 to P9) shown in FIG. Moreover, the temperature difference between each part of the foamed resin laminate 1 is the maximum value data and the minimum value data among the temperature data measured at the nine temperature measurement positions (points P1 to P9) shown in FIG. The difference value, that is, the maximum temperature difference.

  As shown in FIG. 3A, when the average plate temperature of the foamed resin laminate 1 is 100 ° C. lower than the decomposition temperature of the foaming agent (195 ° C.), the temperature difference between each part of the foamed resin laminate 1; The correlation with the thickness variation of the final foamed resin layer 4b (after foaming) is high. On the other hand, as shown in FIG. 3B, when the average plate temperature of the foamed resin laminate 1 becomes the decomposition temperature of the foaming agent (195 ° C.) (when the average plate temperature is close to the decomposition temperature), the foamed resin laminate 1 However, there is almost no correlation between the temperature difference between the portions of the foamed resin laminate 1 and the variation in the thickness of the final foamed resin layer 4b.

  From the above experimental results, for example, in order to suppress the standard deviation of the thickness of the foamed resin layer 4b to 0.4 mm or less, the average plate temperature (temperature) of the foamed resin laminate 1 is determined from the decomposition of the foaming agent from FIG. It can be seen that the temperature difference between each part of the foamed resin laminate 1 when the temperature is lower than 195 ° C. should be 30 ° C. or less. That is, the inventors control the temperature difference between the foamed resin laminate 1 and each part of the foamed resin laminate 1 in the middle of the heating process, and then heat and foam the foamable resin layer 4a. Thus, it was found that the thickness accuracy of the foamed resin laminate 1 after heating and foaming can be improved.

(Method for producing foamed resin laminate)
Next, a method for manufacturing a foamed resin laminate according to an embodiment of the present invention based on the above experimental results will be described based on a flowchart. FIG. 4 is a flowchart for illustrating a method for producing a foamed resin laminate according to an embodiment of the present invention.

  As shown in FIG. 4, first, an unfoamed foamable resin layer 4a and an aluminum plate 2 (hard layer 2) are laminated to form a laminate (unfoamed foamed resin laminate 1) (lamination). Process, Step 1, hereinafter referred to as S1, and other steps are also the same). In S1, the aluminum plate 2 is bonded to both surfaces of the foamable resin layer 4a to form a laminated plate.

  The laminate (unfoamed foamed resin laminate 1) is obtained by adhering an aluminum plate 2 having a thickness of 0.15 mm to both surfaces of a foamable resin layer 4a having a thickness of 0.9 mm. The foamable resin layer 4a uses a polypropylene resin as a matrix resin, and uses an ADCA foaming agent (decomposition temperature 195 ° C., manufactured by Eiwa Kasei Kogyo Co., Ltd.) as a foaming agent. The final thickness of the foamed resin layer 4b after heat foaming is designed to be 2.7 mm (three times the thickness before foaming).

  Next, it transfers to the heating process of a laminated board. This heating process will be described in steps S2 to S4. First, a laminated board is put into a hot-air convection heating furnace (for example, the said gas heating type continuous heating furnace), and the heating of a laminated board is started (S2). When heating of the laminated plate is started, the temperature of the laminated plate rises.

Next, the laminated plate is heated so that the temperature Ts of the laminated plate satisfies the following formula (A) and the temperature difference ΔTs between each part of the laminated plate satisfies the following formula (B) (S3). When the gas heating type continuous heating furnace is specifically described as an example, the temperature Ts of the laminate satisfies the following formula (A) with _respect to the decomposition temperature _{Tf of the} foaming agent contained in the foamable resin layer 4a, and Before the heating of the laminated plate is started, the heating control and the feed control of the gas heating type continuous heating furnace are performed so that the temperature difference ΔTs between each part of the laminated plate satisfies the following formula (B) (S2 Adjust and set in advance. And a laminated board is heated in a gas heating type continuous heating furnace. In this embodiment, the temperature Ts of a laminated board means the temperature (surface temperature) of the aluminum plate 2 (hard layer 2) of the laminated boards.

(Equation 1)
T _f −100 ° C. ≦ Ts ≦ T _f −50 ° C. (A)
T _f : decomposition temperature of foaming agent, Ts: temperature of laminate (foamed resin laminate) (Equation 2)
ΔTs ≦ 30 ℃ (B)
ΔTs: Temperature difference between each part of the laminate (foamed resin laminate)

  In addition, regarding the heating control and feed control of the gas heating type continuous heating furnace, the temperature Ts of the laminated plate is once heated to the range shown by the formula (A) to keep the temperature range, and each part of the laminated plate at that time The temperature difference ΔTs between them may be controlled so as to fall within the range represented by the equation (B) (temperature variation is suppressed), or the temperature Ts of the laminated plate may be substantially the same as the equations (A) and (B). It is good also as control to satisfy | fill.

  In addition, when heating is performed so that the temperature Ts of the laminated plate satisfies the formula (A), the heating control and the feed control of the gas heating type continuous heating furnace are performed so that the average temperature Tsm of each part of the laminated plate satisfies the formula (A). It also means the case of heating by adjusting and setting, and the case of heating by adjusting and setting the heating control and feed control so that all the temperatures of each part of the measured laminate satisfy the formula (A) means.

  In addition, heating is performed so that the temperature difference ΔTs between the respective parts of the laminated plate satisfies the formula (B). In the gas heating type continuous heating furnace, the maximum temperature difference ΔTsmax between the respective parts of the laminated plate satisfies the formula (B). This refers to heating by adjusting and setting the heating control and feed control.

And after heating the said laminated board so that temperature Ts of a laminated board may satisfy _| fill (A) Formula, and the temperature difference (DELTA) Ts between each part of the said laminated board may satisfy _| fill (B) Formula, it is more than decomposition temperature _Tf of a foaming agent The laminate is heated to foam the foamable resin layer 4a (S4). And the heating of a laminated board is complete | finished (S5).

  Thus, in the middle stage in the heating process of the laminated board having the foamable resin layer 4a, the temperature of the laminated board and the temperature difference between each part of the laminated board satisfy the above-mentioned formulas (A) and (B), respectively. Thus, even if the laminated plate is heated and foamed by the convection heat transfer heating method by controlling the heating of the laminated plate and then foaming the foamable resin layer 4a, the laminated plate after heating and foaming (heating The thickness accuracy of the foamed resin laminate 1) after foaming can be improved.

(Further conditions for the temperature Ts of the laminate before heating the laminate above the decomposition temperature of the foaming agent)
In step 3 (S3), it is preferable to heat the laminate so that the temperature Ts of the laminate further satisfies the following expression (C). That is, in step 3 (S3), it is preferable that Ts does not exceed Tm (the deflection temperature under load of the unfoamed laminate).
(Equation 3)
Ts ≦ Tm (C)
Tm: deflection temperature under load of unfoamed laminate

  Here, similarly to the above-described contents, regarding the heating control and feed control of the gas heating type continuous heating furnace, the temperature Ts of the laminated plate is once heated to the range shown by the formulas (A) and (C). Control may be performed such that the temperature range is maintained and the temperature difference ΔTs between the respective parts of the laminated board at that time is within the range represented by the formula (B) (temperature variation is suppressed), or the laminated board temperature Ts. May be controlled so that the expressions (A), (B), and (C) are satisfied almost simultaneously.

  In addition, when heating is performed so that the temperature Ts of the laminated plate satisfies the formula (C), the heating control and the feed control of the gas heating type continuous heating furnace are performed so that the average temperature Tsm of each part of the laminated plate satisfies the formula (C). It also means the case of heating by adjusting and setting, and the case of heating by adjusting and setting the heating control and feed control so that the temperature of each part of the measured laminate meets all the formula (C) means.

Then, after heating the laminate so that the temperature Ts of the laminate satisfies the formulas (A) and (C) and the temperature difference ΔTs between each part of the laminate satisfies the formula (B), The laminate is heated to the decomposition temperature _Tf or higher to foam the foamable resin layer 4a (S4). And the heating of a laminated board is complete | finished (S5).

  Thus, by adding the condition of the above formula (C) to the temperature control in step 3, it is possible to prevent the deformation of the laminated board in the unfoamed state, and as a result, the laminated board after heating and foaming. Thickness accuracy can be further improved.

(About Ts ≦ Tm)
The deflection temperature under load refers to the temperature when the temperature of the test piece reaches a certain value by raising the temperature of the test piece with a predetermined load applied to the test piece. The test method is defined in JIS K7191.

  Here, as an experimental example, a foamed resin laminate 11 shown in FIG. 5A was used. The foamed resin laminate 11 is a rectangular plate having a width of 15 mm and a length of 200 mm. The foamed resin laminate 11 is obtained by bonding an aluminum plate 12 (5182-O material) having a thickness of 0.3 mm to both surfaces of a foamable resin layer 14a having a thickness of 0.9 mm. For the foamable resin layer 14a, a polypropylene resin was used as the matrix resin, and an ADCA foaming agent (decomposition temperature 195 ° C., manufactured by Eiwa Kasei Kogyo Co., Ltd.) was used as the foaming agent. The final thickness of the foamed resin layer after heat foaming is designed to be 2.7 mm (three times the thickness before foaming).

  Further, the deflection temperature under load of the foamed resin laminate 11 (unfoamed state) is 138 ° C. (measured according to JIS K7191-1 and K7191-2. Bending stress: 1.8 MPa, flat width, test piece dimensions: Length 80 mm × width 10 mm, bending strain: 0.2%, temperature increase rate: 120 ° C./h).

  Next, as shown in FIG. 5 (b), the experimental form was placed on a stage 16 in a thermostatic bath 15 on a foamed resin laminate 11 (non-foamed state) having a width of 15 mm × length of 200 mm, and a predetermined temperature. The foamed resin laminate 11 was heated under the conditions, and the amount of deformation at that time was measured. The measurement results are shown in Table 1.

  As can be seen from Table 1, when the foamed resin laminate 11 is heated for 5 minutes at a load deflection temperature Tm (138 ° C.) or less of the foamed resin laminate 11 (unfoamed state), the deformation amount is 2 mm or less. It was a result. On the other hand, when the foamed resin laminate 11 is heated for 5 minutes at a temperature exceeding the load deflection temperature Tm (138 ° C.) of the foamed resin laminate 11 (unfoamed state), the deformation amount is 25 mm or more. It was. Accordingly, in step 3 (S3) shown in FIG. 4, when the temperature Ts of the laminate is adjusted so as not to exceed the deflection temperature Tm, the deformation of the laminate in the unfoamed state can be prevented. It can be seen that the thickness accuracy of the laminate after heating and foaming can be further improved.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. .

  In the above embodiment, the temperature Ts of the laminated plate satisfies the formula (A) and the temperature difference ΔTs between each part of the laminated plate is 30 ° C. or less, but the temperature difference ΔTs is 25 ° C. or less. You may make it become, and you may make it become 20 degrees C or less. In addition, it is preferable that the temperature difference ΔTs is small as described above. Desirably, the temperature difference is 0 ° C., that is, there is no temperature difference.

1: Foamed resin laminate 2: Aluminum plate (hard layer)
4a: Foamable resin layer 4b: Foamed resin layer

Claims (5)

A laminating step of laminating an unfoamable foamable resin layer and a hard layer to form a laminate;
Included in the foamable resin layer after heating the laminate so that the temperature of the laminate satisfies the following formula (A) and the temperature difference between the parts of the laminate satisfies the following formula (B): A heating step of heating the laminate above the decomposition temperature of the foaming agent,
A method for producing a foamed resin laminate, comprising:
(Equation 1)
T _f −100 ° C. ≦ Ts ≦ T _f −50 ° C. (A)
T _f : Decomposition temperature of the foaming agent, Ts: Temperature of the laminate (Equation 2)
ΔTs ≦ 30 ℃ (B)
ΔTs: Temperature difference between each part of the laminate   The said hard layer consists of a metal plate, The manufacturing method of the foamed resin laminated board of Claim 1 characterized by the above-mentioned.   The method for producing a foamed resin laminate according to claim 2, wherein the metal plate is made of an aluminum plate or an aluminum alloy plate.   The method for producing a foamed resin laminate according to any one of claims 1 to 3, wherein the matrix resin of the foamable resin layer is made of a polyolefin resin. The heating step heats the laminated plate so that the temperature Ts of the laminated plate further satisfies the following formula (C), and then brings the laminated plate to a temperature equal to or higher than the decomposition temperature of the foaming agent contained in the foamable resin layer. The method for producing a foamed resin laminate according to any one of claims 1 to 4, wherein the method is a heating step.
(Equation 3)
Ts ≦ Tm (C)
Tm: deflection temperature under load of unfoamed laminate

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