Manufacturing method of film-laminated resin plate

Abstract

To provide a manufacturing method of a film-laminated resin plate that can suppress an occurrence of warping in a laminate.SOLUTION: The manufacturing method of a film-laminated resin plate includes a preheating step of heating a resin plate 11 before the resin plate 11 is supplied to a hot roll 53. In the preheating step, the resin plate 11 is heated from both sides in a plate thickness direction of the resin plate 11.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for producing a film-laminated resin plate. [Background technology]

[0002] The film-laminated resin plate is manufactured, for example, by laminating a functional film having a dimming function to the surface of a transparent resin plate. The functional film is laminated to one side of the resin plate by an adhesive layer. As a method for laminating a functional film by an adhesive layer, for example, Patent Document 1 discloses a method for manufacturing a laminate in which an adhesive forming an adhesive layer is interposed between a resin plate and a functional film, and then the laminate is sandwiched between a pair of pressure rolls to manufacture a laminate in which the resin plate and the functional film are laminated with the adhesive.

[0003] In some cases, a thermosetting adhesive is used as the adhesive. In this case, the laminate is sandwiched between pressure rolls, and the pressure rolls contacting the functional film heat the functional film, thereby heating the thermosetting adhesive. The heated thermosetting adhesive is thermally cured to bond the resin plate and the functional film. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-4902 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the functional film is heated by a pressure roll to heat the thermosetting adhesive, the functional film is likely to expand, whereas the resin plate does not expand as much as the functional film, and there is a risk that warping will occur in the laminate due to the difference in the amount of expansion between the functional film and the resin plate. [Means for solving the problem]

[0006] To solve the above problems, a manufacturing method for a film-laminated resin plate includes heating a functional film having a thermosetting adhesive layer by a heat roll, pressing the thermosetting adhesive layer against one side of a resin plate transported in a conveying direction, and laminating the functional film to one side of the resin plate by the thermosetting adhesive layer heated by the heat roll to produce a laminate, the manufacturing method for a film-laminated resin plate includes a preheating step of heating the resin plate by a preheating device before the resin plate transported in the conveying direction is subjected to the heat roll, and in the preheating step, the resin plate is heated from both sides in the plate thickness direction by the preheating device.

[0007] According to this, the resin plate is heated from both sides in the plate thickness direction of the resin plate by the preheating process. Therefore, the resin plate expands in the same way on both sides in the plate thickness direction. In other words, the resin plate is suppressed from expanding only on one side in the plate thickness direction. And, by going through the preheating process, the resin plate can be heated before being heated by the heat roll. Therefore, compared with the case where the resin plate is heated only by heating by the heat roll, it is easier to match the expansion amount of the resin plate and the expansion amount of the functional film due to heating. As a result, after the laminate is manufactured, when the functional film and the resin plate cool, the resin plate shrinks on both sides in the plate thickness direction, and the functional film and the resin plate shrink in the same way. This can suppress the occurrence of warping of the laminate caused by the difference in the amount of shrinkage between the resin plate and the functional film.

[0008] In a method for manufacturing a film-laminated resin plate, the functional film is provided between the heat roll and the resin plate while being tensioned, and a post-heating heat roll is disposed downstream of the heat roll in the transport direction, which heats the functional film while pressing the thermosetting adhesive layer against one side of the resin plate, and the temperature of the heat roll may be set lower than the temperature of the post-heating heat roll.

[0009] According to this, the functional film is fed between the heat roll and the resin plate in a state where tension is applied, so that the functional film is easily stretched. Furthermore, the functional film expands and stretches due to heating by the heat roll. The greater the stretch of this functional film, the more likely the laminate is to warp when it shrinks. For this reason, the heating of the functional film by the heat roll is performed at a low temperature to a degree that the thermosetting adhesive layer can generate adhesive force in order to suppress the stretch of the functional film. As a result, the stretch of the functional film can be suppressed at the time of heating by the heat roll. Thereafter, the thermosetting adhesive layer is heated by the post-heating heat roll. The temperature of the post-heating heat roll is higher than the temperature of the heat roll. This allows the adhesive force of the thermosetting adhesive layer to be further increased. As a result, when the laminate cools and the functional film shrinks after heating by the post-heating heat roll, the warping of the resin plate due to the shrinkage of the functional film can be suppressed, and the functional film can be suitably bonded to the resin plate by the thermosetting adhesive layer.

[0010] The manufacturing method for a film-laminated resin plate may include a post-heating step of heating the resin plate from both sides in the plate thickness direction downstream of the heat roll in the conveying direction and upstream of the post-heating heat roll in the conveying direction.

[0011] According to this, the resin plate is heated from both sides in the plate thickness direction of the resin plate in the post-heating step. Therefore, the temperature drop of the laminate that has passed through the heat roll can be suppressed on both sides of the resin plate, and the temperature of the resin plate can be made close to the heating temperature of the post-heating heat roll before the laminate is subjected to the post-heating heat roll. This makes it possible to suppress warping of the laminate while bonding the thermosetting adhesive layer with the thermosetting adhesive layer. Effect of the Invention

[0012] The present invention can suppress the occurrence of warping in the laminate. [Brief description of the drawings]

[0013] [Figure 1]FIG. 1 is a partial cross-sectional view showing a film-laminated resin plate. [Diagram 2] FIG. 2 is a side view that illustrates a temporary lamination device for a film-laminated resin plate. [Diagram 3] FIG. 3 is a side view that illustrates the temporary bonding step. [Figure 4] FIG. 4 is a plan view that illustrates the temporary bonding step. [Diagram 5] FIG. 5(a) is a side view showing a schematic view of the laminate before expansion, and (b) is a side view showing a schematic view of the laminate during expansion. [Figure 6] FIG. 6(a) is a side view showing a schematic diagram of a laminate before expansion, and (b) is a side view showing a schematic diagram of a comparative example after expansion. [Figure 7] FIG. 7 is a side view that illustrates a schematic diagram of a temporary bonding apparatus according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, one embodiment of a method for producing a film-laminated resin plate will be described with reference to Figs. <Film-laminated resin plate> The film-laminated resin plate is useful for various applications such as automobile parts, electronic devices, office automation equipment, machine parts, agricultural materials, fishing materials, transport containers, packaging containers, play equipment, and miscellaneous goods. In this embodiment, the film-laminated resin plate is a window member for a vehicle as an automobile part. Specific examples of the window member for a vehicle include a back door window, a sunroof, and a roof panel. The film-laminated resin plate has a three-dimensional shape.

[0015] As shown in FIG. 1, a film-laminated resin plate 10 includes a resin plate 11 and a functional film 31 bonded to the resin plate 11 by a thermosetting adhesive layer 21. <Resin plate> The resin plate 11 may be made of polycarbonate, polymethylmethacrylate, polyethylene terephthalate, polypropylene, or the like, but in this embodiment, polycarbonate is used for the resin plate 11. The resin plate 11 is manufactured by extrusion molding or injection molding. The resin plate 11 has a first main surface 11a and a second main surface 11b that are opposite to each other in the plate thickness direction.

[0016] <Functional films> The types of the functional film 31 include a heat ray reflection film, a barrier film, a light control film, a Low-E film, a conductive film-forming film, a screen film, a perovskite solar cell, and the like. The type of the functional film 31 is not limited to those described above as long as it can be attached to the resin plate 11 by the thermosetting adhesive layer 21. The functional film 31 is attached to the first main surface 11a of the resin plate 11 by the thermosetting adhesive layer 21.

[0017] <Thermosetting adhesive layer> The thermosetting adhesive forming the thermosetting adhesive layer 21 is an adhesive mainly composed of a thermosetting resin such as phenol resin, melamine resin, or epoxy resin. The thermosetting adhesive is softened by heating and then hardened by a crosslinking reaction. The thermosetting adhesive layer 21 is provided in advance on the entire surface of one side of the functional film 31. Therefore, the functional film 31 has the thermosetting adhesive layer 21 integrally therewith. The thermosetting adhesive layer 21 does not generate adhesive force at room temperature and can be deformed integrally with the functional film 31. In addition, the thermosetting adhesive layer 21 generates adhesive force when heated to a predetermined temperature. As the heating of the thermosetting adhesive layer 21 progresses further, the crosslinking reaction progresses and strongly bonds the objects together.

[0018] <Manufacturing method of film-laminated resin plate> The manufacturing method of the film-laminated resin plate 10 is a method of manufacturing the laminate 12 by laminating a functional film 31 having a thermosetting adhesive layer 21 to a first main surface 11a, which is one surface of the resin plate 11. Then, the thermosetting adhesive layer 21 of the laminate 12 is fully cured to complete the film-laminated resin plate 10. Therefore, the laminate 12 is a precursor of the film-laminated resin plate 10. The laminate 12 is a flat plate that does not have a three-dimensional shape.

[0019] The manufacturing method of the film-laminated resin plate 10 includes a preheating step of heating the resin plate 11, and a temporary lamination step of laminating the functional film 31 to the first main surface 11a of the heated resin plate 11.

[0020] The preheating step and the temporary bonding step are performed using a temporary bonding device 40 . <Temporary lamination device> As shown in Figures 2 and 3, the temporary bonding apparatus 40 includes a conveying device 41 for the resin plate 11, a pressure roll 51 including a heat roll 53 that presses the functional film 31 against the resin plate 11 while heating it, a preheating device 61 that preheats the resin plate 11, and a supply device 71 for the functional film 31.

[0021] The conveying device 41 includes a plurality of conveying rollers 42. The plurality of conveying rollers 42 are arranged at intervals in the conveying direction X of the resin plate 11. Note that a direction perpendicular to each of the main surfaces 11a, 11b of the resin plate 11 conveyed in the conveying direction X is referred to as a vertical direction Z. The vertical direction Z coincides with the plate thickness direction of the resin plate 11 being conveyed.

[0022] The supply device 71 includes a film supply roll 72 and a tension roller 73. The supply device 71 is disposed above the transported resin plate 11 in the vertical direction Z. The film supply roll 72 is formed by winding a functional film 31 having a thermosetting adhesive layer 21 in a roll shape. The tension roller 73 applies tension to the functional film 31 sent out from the film supply roll 72.

[0023] The pressure roll 51 is disposed in the middle of the transport path of the resin plate 11. The pressure roll 51 includes a support roll 52 and a heat roll 53. The support roll 52 and the heat roll 53 are disposed facing each other in the vertical direction Z. The support roll 52 supports the resin plate 11 transported by the transport device 41 from the second main surface 11b side.

[0024] The support roll 52 and the heat roll 53 are spaced apart in the vertical direction Z with a gap slightly smaller than the sum of the thickness of the resin plate 11 and the thickness of the functional film 31 including the thermosetting adhesive layer 21. The heat roll 53 is heated by a heat source (not shown). The temperature of the heat roll 53 refers to the surface temperature of the heat roll 53. The temperature of the heat roll 53 is controlled to a desired temperature by a control device (not shown). The support roll 52 may also be a heat roll that can be heated by a heat source (not shown).

[0025] The functional film 31 sent out from the film supply roll 72 is wound around a part of the circumferential surface of the heat roll 53. In detail, the functional film 31 is wound around the heat roll 53 so that the functional film 31 contacts a part of the circumferential surface of the heat roll 53 in the circumferential direction. The rotation of the heat roll 53 pulls out the functional film 31 from the film supply roll 72 and sends out the pulled out functional film 31 in the transport direction X. At this time, the tension roller 73 applies tension to the functional film 31, thereby suppressing slack in the functional film 31.

[0026] The heated roll 53 presses the functional film 31 against the first main surface 11a of the transported resin plate 11 from above. At this time, heat of the heated roll 53 is transferred through the functional film 31 to the thermosetting adhesive layer 21. Due to this heat transfer, the thermosetting adhesive layer 21 is heated by the heated roll 53.

[0027] The preheating device 61 is disposed upstream of the pressure roll 51 and the heat roll 53 in the conveying direction X. The preheating device 61 is made of an IR heater. In addition to the IR heater, the preheating device 61 may be a hot air drying oven or a preheating roller. The preheating device 61 includes a pair of a plate-shaped first heating section 62 facing the first main surface 11a of the resin plate 11 and a plate-shaped second heating section 63 facing the second main surface 11b of the resin plate 11. The second heating section 63 is disposed between the conveying rollers 42 adjacent to each other in the conveying direction X. The second heating section 63 is disposed below the resin plate 11 being conveyed. The first heating section 62 is disposed above the resin plate 11 being conveyed. Each of the first heating section 62 and the second heating section 63 of the preheating device 61 is controlled to a desired temperature by a control device (not shown).

[0028] 4, a direction perpendicular to the conveying direction X and the up-down direction Z is defined as a depth direction Y. The depth direction Y coincides with the width direction of the resin plate 11 and the functional film 31 being conveyed. The dimensions of the first heating section 62 and the second heating section 63 in the depth direction Y are greater than the dimension of the resin plate 11 in the depth direction Y. The dimension of the resin plate 11 in the depth direction Y is greater than the dimension of the functional film 31 in the depth direction Y.

[0029] 3, the first heating section 62 heats the resin plate 11 being transported from the first main surface 11a side, and the second heating section 63 heats the resin plate 11 being transported from the second main surface 11b side. That is, the preheating device 61 heats the resin plate 11 being transported in the transport direction X from both sides in the plate thickness direction before the resin plate 11 is subjected to the heat roll 53. The first heating section 62 heats the first main surface 11a over the entirety in the depth direction Y, and the second heating section 63 heats the second main surface 11b over the entirety in the depth direction Y.

[0030] <Temperature of heat roll> The temperature of the heat roll 53 is set to a temperature at which the thermosetting adhesive layer 21 can be heated until it generates adhesive strength. The thermosetting adhesive layer 21 has a first temperature T1 at which it starts to generate adhesive strength as it is heated, and a second temperature T2 at which it fully hardens as it is heated. The heat roll 53 heats the thermosetting adhesive layer 21 through the functional film 31 so that the temperature of the thermosetting adhesive layer 21 becomes an intermediate temperature T3 that is higher than the first temperature T1 and lower than the second temperature T2. The intermediate temperature T3 is a temperature at which the thermosetting adhesive layer 21 can generate adhesive strength that allows the functional film 31 to be bonded to the resin plate 11 without slipping.

[0031] The heat of the heated roll 53 is also transferred to the functional film 31. In other words, the heat of the heated roll 53 is absorbed by the functional film 31. For this reason, even if the temperature of the heated roll 53 is set to the intermediate temperature T3, the temperature of the thermosetting adhesive layer 21 does not reach the intermediate temperature T3. For this reason, the temperature of the heated roll 53 is set slightly higher than the intermediate temperature T3, taking into account the heat transfer to the functional film 31. As a result, when the functional film 31 is heated by the heated roll 53, the thermosetting adhesive layer 21 reaches the intermediate temperature T3.

[0032] <Preheating device temperature> The temperature of the first heating section 62 and the temperature of the second heating section 63 are the same. The temperatures of the first heating section 62 and the second heating section 63 are set to a temperature that aims to match the amount of expansion of the resin plate 11 in the conveying direction X and the depth direction Y caused by heating by the first heating section 62 and the second heating section 63 with the amount of expansion of the functional film 31 heated by the heat roll 53 in the conveying direction X and the depth direction Y. Note that matching the amount of expansion of the resin plate 11 with the amount of expansion of the functional film 31 is not limited to the case where the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 match, but also includes the case where the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 are made close to each other within a range that can suppress warping of the laminate 12. When making the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 close to each other, it is preferable to make the difference between the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 as small as possible.

[0033] Here, a method for matching the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 will be described. The linear expansion coefficient due to the material of the resin plate 11 is [α1], and the linear expansion coefficient due to the material of the functional film 31 is [α2]. The temperature change amount of the resin plate 11 before and after heating is [ΔH1], and the temperature change amount of the functional film 31 before and after heating is [ΔH2]. The amount of expansion of the resin plate 11 is represented by the integrated value of the linear expansion coefficient α1 and the temperature change amount ΔH1, and the amount of expansion of the functional film 31 is represented by the integrated value of the linear expansion coefficient α2 and the temperature change amount ΔH2.

[0034] When the resin plate 11 and the functional film 31 are made of the same material, the linear expansion coefficient and the amount of temperature change are also the same, so by making the heating temperatures of the resin plate 11 and the functional film 31 the same, the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 can be matched.

[0035] When the resin plate 11 and the functional film 31 are made of different materials as in this embodiment, the amount of expansion of the resin plate 11 can be matched with the amount of expansion of the functional film 31 by adjusting the amount of temperature change ΔH1 of the resin plate 11 and the amount of temperature change ΔH2 of the functional film 31. The amount of temperature change ΔH1 of the resin plate 11 is adjusted by adjusting the temperature of the preheating device 61, and the amount of temperature change ΔH2 of the functional film 31 is adjusted by adjusting the temperature of the heated roll 53.

[0036] After the laminate 12 is manufactured by adjusting the temperature change amount, that is, the temperature, so that the expansion amount of the resin plate 11 and the expansion amount of the functional film 31 match with each other by the above method, the shape and the like of the manufactured laminate 12 are observed. Then, based on the observation results, the temperature change amount may be readjusted so that warping of the laminate 12 is suppressed.

[0037] Next, a method for matching the amount of expansion of the resin plate 11 and the amount of expansion of the functional film 31 will be specifically described. Since the functional film 31 is a thin film, it is easy for the temperature to rise and the resin plate 11 to expand when heated. On the other hand, since the resin plate 11 is a plate having a thickness greater than that of the functional film 31, it receives a larger amount of heat and is less likely to rise in temperature and expand than the functional film 31. In addition, since the functional film 31 and the resin plate 11 are made of different materials, they have different linear expansion coefficients. Taking these factors into consideration, the temperature of the heat roll 53 and the temperatures of the first heating section 62 and the second heating section 63 are set so that the amount of expansion of the resin plate 11 in the transport direction X and the depth direction Y matches the amount of expansion of the functional film 31 heated by the heat roll 53 in the transport direction X and the depth direction Y.

[0038] The temperature of the heated roll 53 is set to a temperature higher than the intermediate temperature T3 as described above. The temperatures of the first heating section 62 and the second heating section 63 are set to a temperature higher than the temperature set for the heated roll 53. However, if the temperature of the resin plate 11 exceeds the glass transition point due to heating by the first heating section 62 and the second heating section 63, the resin plate 11 will be plastically deformed, so the temperatures of the first heating section 62 and the second heating section 63 are set to a temperature lower than the glass transition point of the resin plate 11. The temperatures of the first heating section 62 and the second heating section 63 are actually measured by an experiment using the resin plate 11 and the functional film 31.

[0039] <Explanation of pre-heating process and temporary lamination process> Next, the preheating step and the temporary lamination step will be described. As shown in FIG. 2, in the temporary lamination device 40, the resin plate 11 is transported in the transport direction X by the transport roller 42 of the transport device 41. On the upstream side of the pressure roll 51 in the transport direction X, the transported resin plate 11 is heated over the entire depth direction Y by the first heating section 62 and the second heating section 63. The resin plate 11 is heated at the same temperature from both sides in the plate thickness direction. This performs the preheating process. Therefore, the preheating process is a process in which the resin plate 11 transported in the transport direction X is heated by the preheating device 61 before the resin plate 11 is subjected to the heat roll 53. In the preheating process, the resin plate 11 is heated by the preheating device 61 from both sides in the plate thickness direction of the resin plate 11.

[0040] The functional film 31 is fed from the film supply roll 72 between the support roll 52 of the pressure roll 51 and the heat roll 53 and between the heat roll 53 and the resin plate 11. Therefore, the functional film 31 is provided between the heat roll 53 and the resin plate 11 in a state where tension is applied.

[0041] As shown in FIG. 3, the fed functional film 31 is pushed by the heat roll 53 toward the first main surface 11a of the resin plate 11 that has been conveyed. Thereby, the thermosetting adhesive layer 21 is pressed against the first main surface 11a of the resin plate 11 and is heated by the heat roll 53.

[0042] At this time, according to the above temperature setting, the functional film 31 is heated by the heat roll 53 and the resin plate 11 is heated by the first heating unit 62 and the second heating unit 63 so that the functional film 31 and the resin plate 11 expand with the same expansion amount in the conveyance direction X and the depth direction Y. Therefore, the preheating step is a step for matching the expansion amount of the functional film 31 due to heating by the heat roll 53 and the expansion amount of the resin plate 11 due to heating by the preheating device 61.

[0043] Then, the temperature of the thermosetting adhesive layer 21 rises to an intermediate temperature T3 at which adhesive force is generated by heating with the heat roll 53. The thermosetting adhesive layer 21 whose temperature has risen to the intermediate temperature T3 is pressed against the first main surface 11a of the resin plate 11 by the heat roll 53. Thereby, since the thermosetting adhesive layer 21 is bonded to the first main surface 11a of the resin plate 11, the functional film 31 is bonded to the first main surface 11a of the resin plate 11. At this time, since the thermosetting adhesive layer 21 is before full curing, the functional film 31 is temporarily bonded to the first main surface 11a of the resin plate 11. Thereby, the temporary bonding step is carried out.

[0044] The adhesive strength of the thermosetting adhesive layer 21 generated by heating at the intermediate temperature T3 is smaller than that in the case of full curing, but the positional deviation of the functional film 31 with respect to the resin plate 11 is suppressed. Then, the functional film 31 is temporarily bonded to the resin plate 11 by the thermosetting adhesive layer 21, and a laminate 12 including the resin plate 11 and the functional film 31 is manufactured. Therefore, the manufacturing method of the film-laminated resin plate 10 is a method of manufacturing the laminate 12 by pressing the thermosetting adhesive layer 21 against the first main surface 11a of the resin plate 11 conveyed in the conveying direction X while heating the functional film 31 having the thermosetting adhesive layer 21 by the heat roll 53, and bonding the functional film 31 to the first main surface 11a of the resin plate 11 by the thermosetting adhesive layer 21 heated by the heat roll 53.

[0045] In the laminate 12, the resin plate 11 and the functional film 31 cool down in the portion downstream of the heat roll 53 in the transport direction X. As a result, the resin plate 11 and the functional film 31 contract. At this time, since the resin plate 11 and the functional film 31 have expanded by the same amount in the transport direction X and the depth direction Y, the resin plate 11 and the functional film 31 also contract in the same manner in the transport direction X and the depth direction Y.

[0046] Next, a main lamination process (not shown) is performed. In this process, the laminate 12 is subjected to a main curing device (not shown) to main cure the thermosetting adhesive layer 21. The laminate 12 is heated at a predetermined temperature for a predetermined time by the main curing device. As a result, the resin plate 11 and the functional film 31 are main laminated by the thermosetting adhesive layer 21, and a film-laminated resin plate 10 is produced.

[0047] <Comparison with Comparative Examples> 5(a) and 6(a) show a laminate 12 in which a functional film 31 is bonded to a first main surface 11a of a resin plate 11. In this laminate 12, the resin plate 11 is not preheated. FIG. 5(b) shows a laminate 12 manufactured by heating with a heated roll 53 after a preheating step, and FIG. 6(b) shows a comparative laminate 100 manufactured by heating with a heated roll 53 without a preheating step. In the following description, dimensional changes in the conveyance direction X and the like will not be described.

[0048] 5(a) and 6(a), the dimension in the depth direction Y of the resin plate 11 that has not been preheated is defined as [L1], and the dimension in the depth direction Y of the functional film 31 that has not been heated by the heat roll 53 is defined as [L2]. As described above, the linear expansion coefficient of the resin plate 11 is defined as [α1], and the linear expansion coefficient of the functional film 31 is defined as [α2].

[0049] The amount of dimensional change in the resin plate 11 in the depth direction Y due to heating by the heated roll 53 is defined as [ΔL1]. The amount of dimensional change in the functional film 31 in the depth direction Y due to heating by the heated roll 53 is defined as [ΔL2]. The dimensional changes ΔL1 and ΔL2 are the amounts of expansion at the dimensions L1 and L2.

[0050] The difference between the temperature of the resin plate 11 in the laminate 12 shown in Figures 5(a) and 6(a) and the temperature of the resin plate 11 after heating by the heated roll 53, i.e., the temperature difference before and after heating of the resin plate 11, is defined as the temperature change amount [ΔH1]. Also, the difference between the temperature of the functional film 31 in the laminate 12 shown in Figures 5(a) and 6(a) and the temperature of the functional film 31 after heating by the heated roll 53, i.e., the temperature difference before and after heating of the functional film 31, is defined as the temperature change amount [ΔH2]. The dimensional change amount ΔL1 of the resin plate 11 is expressed by the following formula (1), and the dimensional change amount ΔL2 of the functional film 31 is expressed by the following formula (2).

[0051] ΔL1=α1×L1×ΔH1…Equation (1) ΔL2=α2×L2×ΔH2…Equation (2) In the comparative example, the resin plate 11 does not undergo a preheating process and is only heated by the heated roll 53. Therefore, the temperature change amount ΔH1 of the resin plate 11 is small. On the other hand, in the laminate 12 of the embodiment, the resin plate 11 is heated by the preheating device 61 and the heated roll 53. Therefore, the temperature change amount ΔH1 of the resin plate 11 is larger than that of the comparative example. Therefore, the dimensional change amount ΔL1 of the resin plate 11 in the embodiment obtained from formula (1) is larger than the dimensional change amount ΔL1 of the resin plate 11 in the comparative example, as can be seen by comparing Figures 5(b) and 6(b).

[0052] In addition, the functional film 31 is heated by the heat roll 53 in the same manner in both the embodiment and the comparative example. Therefore, the temperature change amount ΔH2 of the functional film 31 is the same in the embodiment and the comparative example, and the dimensional change amount ΔL2 is also almost the same, as shown in Figures 5(b) and 6(b).

[0053] Therefore, as shown in FIG. 6(b), in the comparative example, the dimensional change amount ΔL2 of the functional film 31 is large relative to the dimensional change amount ΔL1 of the resin plate 11, and a large difference occurs between the dimensional change amount ΔL1 of the resin plate 11 and the dimensional change amount ΔL2 of the functional film 31. In other words, it becomes difficult to match the expansion amount of the resin plate 11 and the expansion amount of the functional film 31. As a result, when the laminate 100 cools, the functional film 31 shrinks significantly while the resin plate 11 hardly shrinks at all, so that the resin plate 11 follows the shrinkage of the functional film 31 due to the thermosetting adhesive layer 21. For this reason, the laminate 100 is likely to warp due to the large difference between the dimensional changes ΔL1 and ΔL2.

[0054] In contrast, as shown in FIG. 5(b), in the laminate 12 that has been subjected to the preheating step, the temperature change amount ΔH1 of the resin plate 11 is large, and therefore the dimensional change amount ΔL1 of the resin plate 11 is also large. Therefore, in the embodiment, a large difference is unlikely to occur between the dimensional change amount ΔL1 of the resin plate 11 and the dimensional change amount ΔL2 of the functional film 31. In other words, the expansion amount of the resin plate 11 and the expansion amount of the functional film 31 are easily matched. Therefore, when the laminate 12 cools, both the resin plate 11 and the functional film 31 shrink in the same manner. Therefore, even if the resin plate 11 and the functional film 31 are bonded together by the thermosetting adhesive layer 21, the warping of the laminate 12 caused by the large difference between the dimensional change amount ΔL1 and the dimensional change amount ΔL2 can be suppressed.

[0055] <Actions and Effects of the Embodiments> The operation and effects of this embodiment will be described. (1) When the film-laminated resin plate 10 is manufactured, the resin plate 11 is heated from both sides in the plate thickness direction of the resin plate 11 in a preheating process. Therefore, the resin plate 11 is suppressed from expanding only on one side in the plate thickness direction. Then, by going through the preheating process, the resin plate 11 can be heated before the heated roll 53 is pressed against the resin plate 11. Therefore, compared with the case where the resin plate 11 is heated only by the heated roll 53, it is easier to match the expansion amount of the resin plate 11 and the expansion amount of the functional film 31. Therefore, after the laminate 12 is manufactured, when the functional film 31 and the resin plate 11 cool, the resin plate 11 shrinks on both sides in the plate thickness direction, and the functional film 31 and the resin plate 11 shrink in the same manner. As a result, the occurrence of warping of the laminate 12 caused by the difference in the amount of shrinkage can be suppressed. Since the occurrence of warping of the laminate 12 can be suppressed, the occurrence of defects caused by warping of the laminate 12 can be suppressed when the laminate 12 is transported to equipment that performs the main bonding step.

[0056] (2) Since the resin plate 11 is heated from both sides in the plate thickness direction in the preheating process, the preheating process can also suppress the occurrence of warping in the resin plate 11. This can suppress the resin plate 11 from becoming difficult to insert between the support roll 52 and the heated roll 53 due to warping of the resin plate 11.

[0057] (3) The resin plate 11 is heated in a preheating step before being subjected to the heated roll 53. Therefore, when the functional film 31 is pressed against the resin plate 11 by the heated roll 53, the amount of heat taken from the functional film 31 to the resin plate 11 can be reduced. Therefore, in order to ensure the amount of heat required for heating the thermosetting adhesive layer 21, the amount of the functional film 31 wrapped around the heated roll 53 can be prevented from increasing. As the amount of the functional film 31 wrapped around the heated roll 53 increases, the tension applied to the functional film 31 increases in order to prevent the functional film 31 from slackening. However, since the amount of the functional film 31 wrapped around the heated roll 53 can be prevented from increasing, the tension applied can be prevented from increasing. As a result, the extension of the functional film 31 due to the application of tension can be prevented, and the warping of the laminate 12 caused by the extension can be prevented.

[0058] (4) The resin plate 11 is heated in a preheating process before being subjected to the heated roll 53. This reduces the amount of heat absorbed by the resin plate 11 when the functional film 31 is pressed against the resin plate 11 by the heated roll 53. This prevents the rotation speed of the heated roll 53, i.e., the transport speed of the resin plate 11, from slowing down in order to transmit the amount of heat required to generate adhesive force in the thermosetting adhesive layer 21 to the functional film 31.

[0059] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.

[0060] As shown in FIG. 7, the temporary lamination device 40 includes a post-heating heat roll 54 in addition to the heat roll 53. The post-heating heat roll 54 is disposed downstream of the heat roll 53 in the conveying direction X. The post-heating heat roll 54 presses the thermosetting adhesive layer 21 against the first main surface 11a of the resin plate 11 while heating the functional film 31. The temporary lamination device 40 may also include a post-heating support roll 55 that is paired with the post-heating heat roll 54. The post-heating support roll 55 is disposed downstream of the support roll 52 in the conveying direction X. The post-heating support roll 55 supports the laminate 12 obtained through the temporary lamination process from the second main surface 11b side of the resin plate 11. The post-heating support roll 55 may also be a heat roll that can be heated by a heat source (not shown).

[0061] The post-heating heat roll 54 and the post-heating support roll 55 are spaced apart in the vertical direction Z with a gap slightly smaller than the thickness of the laminate 12 therebetween. The temperature of the post-heating heat roll 54 is determined according to the amount of heat applied to the laminate 12. The amount of heat is the product of the heating temperature and the heating time. For example, when the laminate 12 is heated with a desired amount of heat, the lower the temperature of the post-heating heat roll 54 is set, the longer the heating time will be. The heating time by the post-heating heat roll 54 becomes longer as the transport speed of the laminate 12 is slowed.

[0062] The temperature of the post-heating heat roll 54 is appropriately set according to the heating time by the post-heating heat roll 54. For example, the temperature of the post-heating heat roll 54 may be set higher than the surface temperature of the heat roll 53. In other words, the temperature of the heat roll 53 may be set lower than the temperature of the post-heating heat roll 54. In this case, the temperature of the heat roll 53 is set slightly higher than the first temperature T1 and lower than the intermediate temperature T3 in the embodiment. The temperature of the post-heating heat roll 54 is set slightly lower than the second temperature T2 at which the thermosetting adhesive layer 21 is fully cured by heating.

[0063] The temporary bonding apparatus 40 includes a post-heating apparatus 81 in addition to a pre-heating apparatus 61. The pre-heating apparatus 61 includes a first heating section 62 and a second heating section 63, similar to the embodiment. The pre-heating device 61 is disposed upstream of the heat roll 53 in the conveying direction X. The post-heating device 81 is disposed downstream of the heat roll 53 in the conveying direction X and upstream of the post-heating heat roll 54 in the conveying direction X. The post-heating device 81 includes a first post-heating section 82 having the same configuration as the first heating section 62, and a second post-heating section 83 having the same configuration as the second heating section 63. Like the pre-heating device 61, the post-heating device 81 heats the resin sheet 11 from both sides in the sheet thickness direction.

[0064] The manufacturing method of the film-laminated resin plate 10 includes a preheating step of preheating the resin plate 11 and a temporary lamination step of temporarily laminating the functional film 31 to the first main surface 11a of the resin plate 11 in order to manufacture the laminate 12. Furthermore, the temporary lamination step includes a post-heating step of heating the resin plate 11 from both sides in the plate thickness direction downstream of the heat roll 53 in the conveying direction X and upstream of the post-heating heat roll 54 in the conveying direction X. Therefore, the manufacturing method of the film-laminated resin plate 10 includes a post-heating step.

[0065] In the temporary lamination step, the functional film 31 is fed between the heated roll 53 and the resin plate 11 while being tensioned by the tension roller 73 of the supply device 71, so that the functional film 31 is likely to stretch. Furthermore, the functional film 31 expands and stretches due to heating by the heated roll 53. The greater the stretching of the functional film 31, the more likely it is to cause warping of the laminate 12 when it shrinks. For this reason, in order to suppress the stretching of the functional film 31, the heating of the heated roll 53 is performed at a low temperature to a degree that allows the thermosetting adhesive layer 21 to generate adhesive force.

[0066] However, since the bonding of the thermosetting adhesive layer 21 by heating with the heat roll 53 is insufficient, a post-heating step is performed, and the thermosetting adhesive layer 21 is bonded by the post-heating heat roll 54. The temperature of the post-heating heat roll 54 at this time is higher than the temperature of the heat roll 53. This increases the adhesive strength of the thermosetting adhesive layer 21. At this time, as described above, the temperature and heating time of the post-heating heat roll 54 are set so that the adhesive strength of the thermosetting adhesive layer 21 can be increased, and a desired amount of heat is applied to the laminate 12 by the post-heating heat roll 54.

[0067] As a result, when the laminate 12 cools and the functional film 31 shrinks after heating by the post-heating heat roll 54, warping of the resin plate 11 due to the shrinkage of the functional film 31 can be suppressed, and the functional film 31 can be suitably bonded to the resin plate 11 by the thermosetting adhesive layer 21.

[0068] In the post-heating device 81, the first post-heating section 82 and the second post-heating section 83 may be provided in a plurality of sections in the conveying direction X. The temperature of the post-heating heat roll 54 may be set lower than the temperature of the heat roll 53. In this case, the heating time by the post-heating heat roll 54 becomes longer in order to obtain a desired amount of heat.

[0069] In the embodiment and the configuration shown in FIG. 7, the first heating section 62 and the second heating section 63 of the preheating device 61 may be divided into a plurality of sections in the conveying direction X. The temporary lamination apparatus 40 including the heat roll 53 and the post-heating heat roll 54 does not necessarily need to include the post-heating device 81. In this case, the temporary lamination process does not include the post-heating process.

[0070] In the preheating device 61, the temperature of the first heating section 62 and the temperature of the second heating section 63 may be different. For example, the temperature of the second main surface 11b side of the resin plate 11 may be lower than that of the first main surface 11a due to contact with the transport roller 42. In order to suppress the temperature difference between the first main surface 11a side and the second main surface 11b side, the temperature of the second heating section 63 may be set higher than that of the first heating section 62.

[0071] The heat roll 53 does not have to include the support roll 52 and the pressure roll 51. In this case, the transport roller 42 may be used instead of the support roll 52. [Explanation of symbols]

[0072] X...conveying direction, 10...film-laminated resin plate, 11...resin plate, 11a...first main surface as one side, 12...laminate, 21...thermosetting adhesive layer, 31...functional film, 53...heat roll, 54...heat roll for post-heating, 61...preheating device.

Claims

1. A method for producing a film-laminated resin plate, the method comprising: heating a functional film having a thermosetting adhesive layer by a heat roll; pressing the thermosetting adhesive layer against one side of a resin plate being transported in a transport direction; and laminating the functional film to one side of the resin plate by the thermosetting adhesive layer heated by the heat roll to produce a laminate, a preheating step of heating the resin plate, which is transported in the transport direction, by a preheating device before the resin plate is subjected to the heat roll; The method for producing a film-laminated resin plate, wherein in the preheating step, the resin plate is heated from both sides in a plate thickness direction of the resin plate by the preheating device.

2. the functional film is provided between the heat roll and the resin plate in a tensioned state, and a post-heating heat roll is disposed downstream of the heat roll in the transport direction, the post-heating heat roll pressing the thermosetting adhesive layer against one side of the resin plate while heating the functional film; The method for producing a film-laminated resin plate according to claim 1 , wherein the temperature of the heat roll is set lower than the temperature of the post-heating heat roll.

3. The method for manufacturing a film-laminated resin plate according to claim 2, further comprising a post-heating step of heating the resin plate from both sides in the plate thickness direction downstream of the heat roll in the conveying direction and upstream of the post-heating heat roll in the conveying direction.

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