JPH1158396A - Manufacture of laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of a thin wall section on the end of a fitting channel of a skin on a laminate with the surface of different colors or patterns with the fitting channel as its boundary. SOLUTION: Two sheet materials 31A and 32A with their surfaces of different colors or patterns are so overlapped as to bring respective surfaces into contact each other, and connected together integrally on a connecting section 33 formed along two side edges 31a and 32a and having the shape of cutting off respective surfaces obliquely on both ends of the one side of straight shape to form a composite sheet material 30A. The composite sheet material is opened and clamped between a first molding tool 10 and a second molding tool 20 so that the sheet materials conform to a slit forming plate 12 with a slit-shaped channel 34A formed on the surface side of the connecting section protruding from a first molding face of the first molding tool, and the surface of the composite sheet material is brought into contact with a first molding face 11 of the first molding tool, and a synthetic resin material forming a base when being cured is filled between the pattern of the sheet and a second molding face 21 of the second molding tool to manufacture a laminate formed of a base coated with the skin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminate in which a base material is covered with a skin, and more particularly to a method for producing a laminate in which the surface of the skin has a different color or pattern with a wood grain groove as a boundary.

[0002]

2. Description of the Related Art For example, in the case of a plate-shaped synthetic resin product such as an automobile door trim, if the upper half and the lower half have different surface colors or patterns in order to enhance the decorativeness, it is common to use such a material. Is prepared by molding the upper half and the lower half separately to prepare a different skin color or pattern, and then integrating them by caulking or the like. Also, in the case where such a plate-shaped synthetic resin product is manufactured by suctioning and bonding the heated and softened skin to the surface of the integrally molded base material by negative pressure and bonding the upper and lower parts with the parting line as a boundary, It is also conceivable to use a skin material having a different surface color or pattern from the lower half.

[0003]

However, the first problem is to be solved.
In the prior art, there is a problem in that the forming process is required separately for the upper half and the lower half, and the assembling process is also required, so that the manufacturing cost increases. Further, in the second prior art, the manufacturing cost is reduced, but in addition to the problem that the skin material is displaced along the surface of the base material at the time of suction, the parting line shape is meandering and the appearance is deteriorated. A flat door trim surface cannot be given a luxurious feel simply because it is color-coded or patterned.

In order to solve these problems, the applicant has previously proposed a method for manufacturing a laminate according to Japanese Patent Application No. 9-11991. This is to heat and soften a sheet material which has a surface having a different color or pattern with the parting line as a boundary and becomes a skin, and then sandwiches the outer peripheral portion between the second molding die and the first molding die. A sheet material whose surface abuts the first molding surface of the first molding die, in which the parting line of the sheet material is brought into contact with the leading edge of the slit forming plate protruding from the first molding surface of the first molding die during clamping. Between the back surface of the second mold and the second molding surface of the second mold, and filling a synthetic resin material as a substrate to produce a laminate in which the substrate is covered with a skin. According to this method, the parting line of the skin is hidden inside the wood-groove groove formed in the skin of the laminate by the slit forming plate, so that even if a considerable winding and bend occurs in the parting line, it cannot be seen from the outside. When viewed from the outside, the grained groove becomes the border of the color or pattern on the surface of the epidermis. Therefore, it is possible to manufacture a laminate having a plurality of colors or patterns with good appearance at low cost, and since a wood grain groove is formed at the boundary of the colors or patterns, the boundary portion has a luxurious three-dimensional appearance. There is something.

However, in the above-mentioned last technique, since both ends of the slit forming plate abut at a substantially right angle with the rising portion formed on the outer periphery of the first forming surface of the first forming die, the wood grain formed by the slit forming plate is formed. Near both sides of both ends of the groove, the skin has a locally large surface with a positive curvature (for example, a shape such as a hemisphere, in which it is necessary to make a cut in the periphery to make it flat, ). For this reason, when it is attempted to form a sheet material having a flat shape (that is, the curvature of the surface is 0), there is a problem that a local thin portion is generated in the sheet material near both ends of the wood cut groove.

An object of the present invention is to solve such a problem and to produce a laminate having a good appearance in which the color or pattern of the surface is divided by parting lines.

[0007]

According to a method of manufacturing a laminate according to the present invention, two sheet materials having different surface colors or patterns are stacked so that their surfaces abut each other.
A composite sheet material is formed by integrally connecting the two sheet materials to each other at a connection portion along one side edge in which both ends of one straight side are obliquely cut off. A slit-shaped groove formed on the surface side of the connecting portion of the composite sheet material is formed on the first forming surface side of the composite sheet material opened substantially flat except for the connecting portion. After being superimposed on the first molding die so as to substantially coincide with the leading edge of the slit forming plate integrally provided on the first molding die so as to protrude from the first molding surface, the first molding die and the most The outer peripheral portion of the composite sheet material is sandwiched between the second molding dies approached to the approach position, and the back surface of the composite sheet material and the second molding surface formed on the second molding die so as to face the first molding surface. Filling the space between the layers with a synthetic resin material that cures and becomes the base material It is an feature.

[0008] A narrow wood-groove groove is formed on the skin of the laminate manufactured according to the present invention by a slit forming plate.
The connecting portion, which is the border of the color or pattern of the skin, is hidden inside the wood grain groove. Since each one side edge serving as a connecting portion of the first and second sheet materials constituting the composite sheet material has a shape obtained by diagonally cutting off both ends of one straight side, in a state where both sheet materials are opened. The vicinity of both ends of the connecting portion of the composite sheet material has a shape with a positive curvature. As described above, since the composite sheet material used in the present invention is provided with a positive curvature in advance in the vicinity of both ends of the slit forming plate, the sheet is formed in the vicinity of both ends of the wood-groove groove formed by the slit forming plate. The material is less likely to have localized excess meat.

It is preferable that a groove is formed on the second molding surface of the second molding die at a position corresponding to the slit forming plate. In this case, a ridge is provided on the back side of the base material so as to surround the groove. It is formed.

The first and second sheet materials used in the present invention are preferably composed of a dense synthetic resin surface layer on the front surface side and a foamed synthetic resin back surface layer on the back surface side. preferable. In this case, the back surface layer made of the foamed synthetic resin is compressed by the pressure when the space between the back surface of the composite sheet material and the second molding surface is filled with the synthetic resin material serving as the base material, The thickness of the back surface layer compressed when the slit forming plate is pulled out is restored.

In the method for manufacturing a laminate according to the present invention, a negative pressure is applied between a first molding die and a composite sheet material having an outer peripheral portion in contact with the first molding die so that the surface of the composite sheet material is reduced by the first molding die. The first molding surface and the slit forming plate are brought into close contact with each other by suction, and the two molding dies are moved closer to the closest position to sandwich the outer peripheral portion of the composite sheet material therebetween. The filling is preferably performed by injecting a synthetic resin material into the space between the back surface of the composite sheet material.

It is preferable that the composite sheet material used in the method for producing a laminate according to the present invention be softened by heating before being laminated on the first mold.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an automobile door trim will be described below with reference to the accompanying drawings. As in the intermediate product shown in FIG. 4, the door trim formed according to the present invention is obtained by covering the outer surface of a rigid base material 40 having a substantially constant thickness with a flexible skin 30 and a lower half portion. Is integrally formed with an armrest portion R of a deep drawing portion. On the front side of the skin 30 of the door trim, a wood-groove groove 34 that is substantially linear or slightly bent over the entire width in the lateral direction is formed, and the color or pattern of the surface is different between the upper side and the lower side. For example, in the case of a door trim having dimensions of about 600 mm × 900 mm, the thickness of each part is 2.5 to 6.0 mm for the base material 40 and 3.4 for the skin 30.
5mm or less, thus 5.95-9.45 for the entire door trim
mm or less.

First, a molding apparatus used in this embodiment will be described with reference to FIGS. The molding apparatus includes a first molding die (lower mold) 10 attached to a lower fixed mold support member (not shown) via a surface plate 19, and an upper movable mold support member (upper) via a surface plate 29. A second molding die (upper die) 20 is attached to the drawing (not shown). A first molding surface 11 having a shape corresponding to the surface of the skin 30 of the door trim is formed on the upper side of the first molding die 10, and an outer peripheral portion 11 a extending outward and flat is formed outside the first molding surface 11. This first
The slit forming plate 12 is formed in a thin plate shape (having a thickness of, for example, 1 to 2 mm) straight or slightly bent when viewed from directly above the molding surface 11 along a position corresponding to the wood grain groove 34 along the door trim. It is implanted and fixed so that it protrudes by the depth of. Between the cavity 13 formed in the first molding die 10 and the first molding surface 11, a large number of intake holes 14 (only a part is shown in the figure) are provided almost all over,
An intake port 15 opened to the cavity 13 is connected to a vacuum source 16 including a vacuum pump, a vacuum tank, and an on-off valve.

The second mold 20 can be approached and separated from the first mold 10 from above. FIGS. 1 and 2 show the separated state, and FIG. 3 shows the closest state. First mold 10
On a lower surface of the second molding die 20 facing the first molding surface 11 on the upper surface, a second molding surface 21 is formed in which a gap between the first molding surface 11 and the door trim in the closest state is the thickness of the door trim. . A groove 22 is formed on the second forming surface 21 at a position corresponding to the slit forming plate 12 fixed to the first forming surface 11. Runners 24 opened in the groove portions 22 are continuously formed on the second molding die 20 and the surface plate 29, and two or more highly reactive resin materials that become the base material 40 by being cured by the reaction are closed. An injection head 45 of a reaction injection molding machine for injecting into the space between the two molds 10 and 20 can be brought into contact with and separated from the outer end opening of the runner 24. Also, the second molding surface 21
Outer peripheral portion 21a formed outside and extending flat outward
As shown in FIG. 3, when the two dies 10 and 20 are in the closest state, they approach the outer peripheral portion 11a of the first molding surface 11 and become the outer skin 30 between them. Is sandwiched between them. Outside the outer peripheral portion 21a, a notch 23 for escaping a part of the holding frames 36a, 36b for holding the outer peripheral portion of the composite sheet material 30A as described below.
Are formed.

Next, referring mainly to FIG. 5 and FIG. 6, the composite sheet material 3 which is adhered to the surface of the base material 40 to form the skin 30 will be described.
0A will be described. The composite sheet material 30A includes a first sheet material 31A for covering the lower half of the base material 40 and a second sheet material 32A for covering the upper half of the base material 40.
32a. Each of the first and second sheet materials 31A and 32A is a thin sheet-like surface layer (for example, a 0.35 mm-thick polypropylene resin sheet, a vinyl chloride resin sheet, etc.) composed of a dense solid layer of a soft thermoplastic resin. ) On the back surfaces of 31b and 32b, back surface layers 31c and 32 made of an elastic sheet-like synthetic resin foam (for example, a vinyl chloride resin foam sheet having a thickness of 2 to 3 mm).
c is laminated and bonded in advance to form a sheet.
And the surface layers 31b, 3 of the second sheet materials 31A, 32A.
2b is different from each other in surface color or pattern.

Such two rectangular sheet materials 31
A and 32A are overlapped so that the surfaces of the surface layers 31b and 32b are in contact with each other, and as shown in FIG. A part is thinned and the end material 35 is cut off from the composite sheet material 30A. As a result, the first and second sheet materials 31A and 32A have their respective surface layers 31b and 32a at the connecting portions 33 along the respective one side edges 31a and 32a in which both ends of one straight side are cut off obliquely. The composite sheet material 30A is integrally connected to each other with 32b inside.
Is formed. The length of this linear portion is made slightly smaller than the length of the slit forming plate 12. As shown in FIG. 6, the composite sheet material 30A can be opened by opening both sheet materials 31A and 32A so as to be substantially flat except for the connecting portion 33.
A slit-shaped groove 34 </ b> A is formed on the surface side of the connecting portion 33.

The composite sheet material 30A thus formed
Since both ends of the connecting portion 33 are cut off obliquely, the vicinity thereof has a surface shape having a positive curvature. The positive curvature increases as the cut-off angle α (see FIG. 5) increases, and the preferable angle α is the height of the rising portion formed on the outer periphery of the first forming surface 11 near both ends of the slit forming plate 12 in contact. Although it depends on the height of the slit forming plate 12 from the first forming surface 11 and the height of the rising portion is 50 to 60 mm, it is 5 to 45 degrees, preferably 15 to 45 degrees.
~ 20 degrees.

Next, a method for manufacturing a laminate using the above-described composite sheet material 30A and a molding apparatus will be described with reference to FIGS. First, as shown in FIG. 6, the composite sheet material 30A is opened flat except for the connecting portion 33, and the outer peripheral portion is held between the holding frames 36a and 36b so that the surface on which the slit-shaped groove 34A is formed is on the lower side. Hold by pinching,
It is softened by heating (for example, 120 ° C.) by a far infrared heater or the like. Then, the holding frames 36a and 36b are lowered, and the outer peripheral portion of the composite sheet material 30A is brought into contact with the outer peripheral portion 11a of the first molding die 10 as shown by the two-dot chain line in FIG. And the space between the composite sheet material 30A is substantially sealed. The horizontal position of the composite sheet material 30A is set so that the slit-shaped groove 34A of the softened and slightly sagged composite sheet material 30A substantially coincides with the leading edge of the thin slit forming plate 12 protruding from the first molding surface 11. If necessary, the slit forming plate 12 may be pushed into the slit-shaped groove 34A as shown by a two-dot chain line in FIG. Then, the negative pressure from the vacuum source 16 is applied to the intake port 15 and the cavity 13.
If it is provided between the lower side of the composite sheet material 30A and the first molding surface 11 of the first molding die 10 through the suction hole 14, the composite sheet material 30A is formed into the first molding surface 11 and the slit forming as shown in FIG. It is attracted and adhered to the plate 12 and the outer peripheral portion 11a.

Due to this suction contact, the composite sheet material 30A is formed near both ends of the slit forming plate 12 which abuts at a right angle to the rising portion formed on the outer periphery of the first molding surface 11.
Is locally formed on a surface having a large positive curvature,
As described above, since the composite sheet material 30A has a surface shape with a positive curvature at both ends of the connecting portion 33 corresponding to the vicinity thereof, the composite sheet material 30A is near both ends of the wood-groove groove formed by the slit forming plate. There is no local thin portion in the sheet material.

Next, the second mold 20 is moved to the first mold 10
The outer peripheral portion 21a of the second molding die 20 abuts on the composite sheet material 30A on the outer peripheral portion 11a of the first molding die 10 as shown in FIG. The molding surfaces 11 and 21 are sandwiched by the outer peripheral portions 11a and 21a, and stopped when the gap between the molding surfaces 11 and 21 becomes the closest to the thickness of the door trim. Then, the injection head 45 of the reaction injection molding machine was brought into contact with the outer end opening of the runner 24, and the injection head 45 was subjected to collision mixing.
A synthetic resin material 40A made of at least one kind of highly reactive material,
Second molding surface 21 of second molding die 20 and composite sheet material 30A
It is injected and filled into the space between the back surface of the substrate.

The filled synthetic resin material 40A rapidly reacts and hardens, and the base material 40 fixed integrally with the skin 30 is formed.
Then, the injection head 45 is detached, the second mold 20 is raised, and the intermediate product of the door trim in a state where the runner portion 41 of the base material 40 and the peripheral portion of the skin 30 are connected as shown in FIG. Take out. As a result, door trim 1
One cycle of 0 molding is completed. And the runner part 41
If an unnecessary portion on the outer periphery of the skin 30 is cut off, the door trim is completed. At the time of this excision, if necessary, the outer peripheral portion of the epidermis 30 may be left slightly, and the remaining outer peripheral portion may be wound inside the outer edge of the base material 40 and adhered. In this embodiment, the synthetic resin material 40 injected from the injection head 45 is used.
A is mixed with a reinforcing material such as glass fiber to increase the strength of the formed base material 40.

In the door trim manufactured according to the above-described embodiment, the connecting portion 33 of the two sheet materials 31A and 32A, which is the boundary of the color or pattern on the surface of the composite sheet material 30A.
The narrow wood grain groove 34 by the slit forming plate 12
Is formed, so that even when a deep throttle portion such as the armrest portion R is integrally formed and the connecting portion 33 is displaced,
The connecting portion 33 of the skin 30 is concealed by entering the inside of the grained groove 34, so that it does not appear outside and become unsightly. Therefore, it is possible to manufacture at low cost a door trim in which the surface having a good appearance is divided into a plurality of colors or patterns.
Further, since the wood grain groove 34 is formed at the boundary of the color or pattern classification, this portion has a luxurious three-dimensional appearance. In this embodiment, in which the composite sheet material 30A is suction-adhered to the first molding surface 11, the slit forming plate 12 easily enters the slit-shaped groove 34A, and thus the connecting portion 3
Since the possibility that the groove 3 is shifted with respect to the slit forming plate 12 is reduced, it is not necessary to increase the depth of the wood groove 34 so much.

In the above-described embodiment, the composite sheet material 3
Each of the sheet materials 31A and 32A of 0A is composed of the surface layers 31b and 32b of the dense synthetic resin on the front side and the back layers 31c and 32c of the foamed synthetic resin on the back side. Molding surface 21 and composite sheet material 3
Back surface layer 31 made of a foamed synthetic resin due to the pressure at the time of injecting and filling the synthetic resin material 40A into a space between the back surface 31A and the back surface 31A.
c, 32c are compressed, and the thickness of the compressed back surface layer when the slit forming plate 12 is pulled out is restored. Thereby, the wood grain groove 34 formed on the surface of the skin 30 has a narrower groove width, so that the appearance is further improved.

In the above-described embodiment, the groove 22 is formed on the second molding surface 21 of the second molding die 20 at a position corresponding to the slit forming plate 12. It is formed on the back side of the material 40. Therefore,
Even when the thickness of the base material 40 is substantially constant, the strength at the portion corresponding to the tip of the groove 34 is not reduced and the strength is not reduced.

In the above embodiment, the composite sheet material 30A that has been softened by heating is brought into close contact with the first molding surface 11 and the slit forming plate 12 by negative pressure, and then the synthetic resin material 40A is placed in the second molding die 20. The space between the second molding surface 21 and the back surface of the composite sheet material 30A is injected and filled.
By doing so, the first forming surface 11 and the slit forming plate 1
Because the adhesion of the composite sheet material 30A to the second 2 is improved,
The finish of the skin 30 is improved. However, depending on the shape or the material of the laminate, the present invention can be carried out without performing heat softening of the composite sheet material 30A or suction adhesion by negative pressure.

In the above embodiment, the first molding die 10
Is a lower mold and the second mold 20 is an upper mold. However, the present invention may be practiced with the first mold 10 as an upper mold and the second mold 20 as a lower mold, , 20 can be implemented so as to face each other in the horizontal direction. In this case, the slit groove 34A on the surface of the composite sheet material 30A
The slit forming plate 12 enters into the inside at the initial stage of the suction adhesion of the composite sheet material 30 </ b> A to the first molding surface 11.

In the above-described embodiment, the base material 40 is formed by the reaction injection molding as described above. However, the present invention is not limited to the second molding surface 21 of the second molding die 20 and the composite sheet material 30A.
The base material 40 is formed by ordinary injection molding using a molten resin material as the synthetic resin material 40A to be filled in the space between the base material 40
It is also possible to carry out by molding.

Further, instead of forming the base 40 by injection molding after closing both the molds 10 and 20 as in the above embodiment, the first mold is formed with the second mold 20 separated. Composite sheet material 30A suction-contacted to mold 10
Alternatively, stamping molding may be performed in which the molten synthetic resin is supplied on the top and the second synthetic mold 20 is lowered to spread the molten synthetic resin. In this case, it is more appropriate to implement the first mold 10 as an upper mold and the second mold 20 as a lower mold.

[0030]

According to the present invention, since the composite sheet material has a shape having a positive curvature near both ends of the connecting portion in advance, both ends of the wood-groove groove formed by the slit forming plate during molding are formed. Local thin portions are less likely to occur near both sides, and therefore, such portions will not be transparent or whitened. In addition, the connecting part that becomes the boundary of the color or pattern of the skin is hidden inside the wood grain groove so it can not be seen from the outside, and the wood grain groove becomes the border line of the color or pattern of the surface of the skin as seen from the outside . This makes it possible to produce a low-cost laminated body having a good appearance and having a plurality of colors or patterns on the surface with the wood grain groove as a boundary.

According to the groove formed on the second molding surface, the groove corresponding to the slit forming plate is formed on the back side of the substrate, so that the ridge surrounding the groove is formed on the second molding surface. The strength does not decrease due to the thinning of the wall pressure at the portion.

If the first and second sheet members are composed of a dense synthetic resin surface layer and a foamed synthetic resin back layer, the back layer compressed when the slit forming plate is pulled out is formed. The thickness is restored, and the width of the wood grain groove after the slit forming plate is pulled out becomes narrower, so that the appearance is further improved.

Further, after the surface of the composite sheet material is brought into close contact with the first molding surface and the slit forming plate by suction, a synthetic resin material as a base material is injected into a space between the second molding surface and the back surface of the composite sheet material. According to the method of filling, the molding of the composite sheet material is not affected by the flow of the synthetic resin material at the time of filling, thereby eliminating the cause of uneven skin thickness. .

Further, according to the composite sheet material which is heated and softened prior to being superimposed on the first molding die, the composite sheet material can be brought into close contact with the first molding surface and the slit forming plate, so that the finished skin can be obtained. Will be better.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a state in which a second mold is separated from one embodiment of a method for manufacturing a laminate according to the present invention.

FIG. 2 is a cross-sectional view showing a state in which a composite sheet material serving as a skin of the embodiment shown in FIG. 1 is suction-adhered to a first molding surface.

FIG. 3 is a cross-sectional view showing a state in which a synthetic resin material which becomes a base material after being cured according to the embodiment shown in FIG. 1 is filled.

FIG. 4 is a cross-sectional view showing a state where a molded intermediate product of the embodiment shown in FIG. 1 is removed.

FIG. 5 is an explanatory diagram of a composite sheet material used in the embodiment shown in FIG.

FIG. 6 is a partially enlarged sectional view taken along line 6-6 in FIG. 5;

[Explanation of symbols]

Reference numeral 10: first molding die, 11: first molding surface, 12: slit forming plate, 20: second molding die, 21: second molding surface, 22 ...
Grooves, 30: skin, 30A: composite sheet material, 31A, 3
2A: sheet material, 31a, 32a: one side edge, 31b,
32b: front surface layer, 31c, 32c: back surface layer, 33: connecting portion, 34A: slit-shaped groove, 40: base material, 40A: synthetic resin material.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 9:00 31:30

Claims (5)

[Claims] 1. Two sheets having different colors or patterns on their surfaces are overlapped so that their surfaces are in contact with each other, and both sheets are formed into a shape in which both ends of one straight side are obliquely cut off. A composite sheet material is formed by integrally connecting with each other at a connection portion along one side edge portion, and the composite sheet material obtained by opening the two sheet materials in a substantially planar shape except for the connection portion is formed by the composite sheet material. Surface is first
A slit-shaped groove formed on the first molding surface formed on the molding die and formed on the surface of the connecting portion of the composite sheet material is provided integrally with the first molding die so as to protrude from the first molding surface. The composite sheet is placed between the first mold and the second mold approached to the closest position after the first mold is overlaid on the first mold so as to substantially coincide with the leading edge of the slit forming plate. The outer peripheral portion of the material is sandwiched, and is cured in a space between the back surface of the composite sheet material and the second molding surface formed opposite to the first molding surface in the second molding die to be a base material. A method for producing a laminate in which a base material is covered with a skin, wherein the laminate is filled with a resin material. 2. The method according to claim 1, wherein a groove is formed on a second molding surface of the second molding die at a position corresponding to the slit forming plate. 3. The first and second sheet members each comprise a surface layer of a dense synthetic resin on the front surface side and a back surface layer of a foamed synthetic resin on the back surface side. The method for producing a laminate according to the above. 4. A negative pressure is applied between the first molding die and the composite sheet material whose outer peripheral portion is in contact with the first molding die, and the surface of the composite sheet material is formed on the first molding surface of the first molding die and After bringing the both molds into close proximity to the slit forming plate by suction and bringing the outer peripheral portion of the composite sheet material therebetween, the second mold surface and the second molding surface are joined together. The method for manufacturing a laminate according to any one of claims 1 to 3, wherein the filling is performed by injecting the synthetic resin material into a space between the sheet material and the back surface. 5. The method for producing a laminate according to claim 1, wherein the composite sheet material is heated and softened prior to being placed on the first molding die.