JP7795079B2 - panel - Google Patents

Description

The present invention relates to a panel that can be used as a luggage board or the like to be installed in the trunk of a vehicle.

Patent Document 1 discloses a panel constructed by attaching thin steel plates to a hollow plate.

JP 2016-7900 A

Panels such as those described in Patent Document 1 are required to be even lighter, and to achieve this, it is necessary to reduce the amount of adhesive used as much as possible. However, reducing the amount of adhesive used can result in insufficient adhesive strength or greater variation in adhesive strength, so it is not easy to reduce the amount of adhesive used to reduce weight while maintaining adhesive strength.

The present invention was made in light of these circumstances, and provides a method for manufacturing panels that have excellent adhesive strength, are lightweight, and can be manufactured efficiently.

The present invention provides a panel manufacturing method comprising a first bonding step and a second bonding step, wherein the first bonding step involves bonding a face material to a substrate to form an adhesive body, and the second bonding step involves bonding a skin material to the adhesive body to form a panel. The first bonding step comprises a first application step and a first sticking step, wherein the first application step involves applying a first adhesive to the face material using a roll coater, and the first sticking step involves sticking the first adhesive-coated surface of the face material to the substrate to form the adhesive body. The second bonding step comprises a second application step and a second sticking step, wherein the second application step involves applying a second adhesive to the skin material using a spray coater, and the second sticking step involves sticking the first adhesive-coated surface of the skin material to the adhesive body. The second sticking step involves sticking the skin material so as to cover at least a portion of the first main surface and side surfaces of the adhesive body and at least a portion of the second main surface of the adhesive body.

As will be shown in the examples and comparative examples described below, the method of the present invention can increase the adhesive strength between the substrate and face material while minimizing the amount of adhesive used, and can also increase manufacturing efficiency while increasing the edge adhesive strength of the skin material.

Various embodiments of the present invention will be described below as examples, and the embodiments shown below can be combined with each other.
Preferably, the method described above further comprises a heating step between the first application step and the first attachment step, in which the first adhesive applied to the face material is heated.
Preferably, the method is as described above, wherein the first adhesive is a moisture-curable polyurethane-based hot melt adhesive.
Preferably, the method is as described above, wherein the second adhesive is a moisture-curable polyolefin-based hot melt adhesive.

FIG. 1A is a cross-sectional view of a panel 1 according to one embodiment of the present invention, FIG. 1B is an enlarged view of region B in FIG. 1A, and FIG. 1C is a view of FIG. 1B from which the skin material 4 and adhesive layer 7 have been removed. 1B (adhesive layers 6, 7 not shown). 10 is an explanatory diagram of a first application step in which a first adhesive 6 a is applied to a face material 3 by a roll coater 9. FIG. 10 is an explanatory diagram of a second application step in which a second adhesive 7a is applied to the skin material 4 by a spray coater 10. FIG.

The following describes embodiments of the present invention. The various features shown in the following embodiments can be combined with each other. Furthermore, each feature can be an independent invention.

1. Structure of Panel 1 A panel 1 according to one embodiment of the present invention will now be described. As shown in Figures 1 and 2, the panel 1 comprises a base material 2, a face material 3, and a skin material 4. The panel 1 preferably has a substantially rectangular parallelepiped shape. The panel 1 can be used as a luggage board or the like to be installed in the trunk of a vehicle.

Let L1 be the length of panel 1 in the first direction, and L2 be the length in the second direction perpendicular to the first direction, where L1 ≥ L2. L1 is, for example, 600 to 1200 mm, specifically, for example, 600, 700, 800, 900, 1000, 1100, or 1200 mm, or may be within a range between any two of the values exemplified here. L1 is 300 to 1200 mm, specifically, for example, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, or 1200 mm, or may be within a range between any two of the values exemplified here. The value of L2/L1 is, for example, 0.3 to 1, specifically, for example, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.0, and may be within a range between any two of the values exemplified here.

The substrate 2 is preferably a plate-shaped member. The thickness of the substrate 2 is 10 to 25 mm, preferably 18 to 22 mm. If the substrate 2 is too thin, the overall deflection of the panel 1 will be too great. On the other hand, if the substrate 2 is too thick, the weight of the panel 1 will be too great. Specific examples of this thickness include 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, and 25 mm, and may be within a range between any two of the values exemplified here. The thickness of the substrate 2 refers to the distance at the point where the distance between the opposing first and second main surfaces 2a, 2b of the substrate 2 is greatest. The substrate 2 preferably has a recess 5, within which the face material 3 is fixed. This prevents the face material 3 from peeling off the substrate 2.

The substrate 2 may be foamed or non-foamed. Furthermore, the substrate 2 may be hollow or solid. The substrate 2 is preferably formed by molding using a mold. In this case, the substrate 2 can be formed into the desired shape before the panel 1 is manufactured, making it easy to handle. Furthermore, the substrate 2 can be shaped to match the desired panel shape, resulting in a product with an optimized shape.

Examples of substrate 2 include bead foam molded articles obtained by bead expansion molding, foamed or non-foamed sheet molded articles obtained by imparting a textured shape to a single foamed or non-foamed resin sheet, and foamed or non-foamed hollow molded articles obtained by molding a foamed or non-foamed cylindrical parison or two resin sheets.

The expanded bead moldings can be made of, for example, expanded polystyrene, expanded acrylonitrile styrene, or expanded polypropylene, and their expansion ratios are, for example, 15 to 50 times, specifically, 15, 20, 25, 30, 35, 40, 45, or 50 times, or may be within a range between any two of the values exemplified here.

The foam parison or foam resin sheet can be made of a polyolefin such as polyethylene or polypropylene, and the foaming ratio of a molded article made using this is, for example, 1.1 to 8 times, specifically, for example, 1.1, 1.5, 2, 3, 4, 5, 6, 7, or 8, or may be within a range between any two of the values exemplified here.

The face material 3 is a plate-shaped member that is adhered to the base material 2 via an adhesive layer 6. The face material 3 is adhered to one or both of the first and second principal surfaces 2a, 2b of the base material 2. The principal surfaces 2a, 2b are, in other words, the front and back surfaces of the base material 2. The principal surfaces 2a, 2b are connected by the side surface 2c. From the perspective of increasing the rigidity of the panel 1, it is preferable that the face material 3 be adhered to both principal surfaces 2a, 2b. From the perspective of weight reduction, it is preferable that the face material 3 be adhered only to principal surface 2a or only to principal surface 2b.

The face material 3 can be made of a material with higher rigidity per unit thickness than the base material 2, such as metal (aluminum, iron, etc.) or fiber-reinforced resin. The thickness of each face material 3 is, for example, 0.05 to 1 mm, with 0.08 to 0.5 mm being preferable. Specific examples include 0.05, 0.08, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.60, 0.70, 0.80, 0.90, and 1.00 mm, and may fall within a range between any two of the values exemplified here. Note that, in this specification, values for thickness, depth, etc. refer to average values unless otherwise specified.

The skin material 4 is adhered to an adhesive body 8 formed by adhering a face material 3 to a substrate 2. The skin material 4 is, in one example, a nonwoven fabric, and can be adhered to the adhesive body 8 via an adhesive layer 7. The first and second main surfaces 8a, 8b of the adhesive body 8 correspond to the first and second main surfaces 2a, 2b of the substrate 2, and the main surfaces 8a, 8b face each other. The side surface 8c of the adhesive body 8 coincides with the side surface 2c of the substrate 2.

More specifically, the skin material 4 is adhered so as to cover at least a portion of the principal surface 8a and the side surface 8c, and at least a portion of the principal surface 8b. As shown in FIG. 1B, the skin material 4 preferably includes first and second skin materials 4a and 4b. Each of the skin materials 4a and 4b is a single sheet of skin material. The skin material 4a preferably covers at least a portion (preferably the entirety) of the principal surface 8a and the side surface 8c, and a portion of the principal surface 8b (preferably the peripheral portion of the principal surface 8b). The skin material 4a preferably covers the boundary between the face material 3 on the principal surface 8b side and the substrate 2. In this case, peeling of the face material 3 on the principal surface 8b side is suppressed. The skin material 4b covers the remainder of the principal surface 8b. The peripheral portions of the skin material 4a and the skin material 4b preferably overlap each other. In this case, gaps between the skin materials 4a and 4b are avoided. Additionally, the skin material 4b may be omitted, and the skin material 4 may consist of only the skin material 4a.

2. Method for Manufacturing Panel 1 The method for manufacturing the panel 1 according to one embodiment of the present invention includes a first bonding step and a second bonding step. Each step will be described in detail below.

(1) First Adhesion Step In the first adhesion step, the face material 3 is adhered to the base material 2 to form an adhered body 8. The first adhesion step includes a first application step and a first attachment step.

(1-1) First Application Step As shown in FIG. 3, in the first application step, a first adhesive 6 a is applied to the face material 3 by a roll coater 9 .

The roll coater 9 is a coating device that uses a coating roll 9a. The adhesive coated on the surface of the coating roll 9a is brought into contact with the object to be coated, thereby applying the adhesive to the object.

In one example, the roll coater 9 includes a coating roll 9a, a doctor roll 9b, and a backup roll 9c. The coating roll 9a and the doctor roll 9b are positioned with a gap 9d between them. The coating roll 9a and the backup roll 9c are positioned with a gap 9e between them. The face material 3 is sandwiched between the coating roll 9a and the backup roll 9c and transported by the coating roll 9a and the backup roll 9c rotating in opposite directions. Furthermore, as the coating roll 9a and the doctor roll 9b rotate in opposite directions, the first adhesive 6a supplied to the upper side of the gap 9d passes through the gap 9d and becomes a thin film 6b of the first adhesive 6a on the coating roll 9a. When the thin film 6b comes into contact with the face material 3 with further rotation of the coating roll 9a, the thin film 6b is transferred to the face material 3 and becomes a coating film 6c of the first adhesive 6a. The thickness of the coating film 6c can be adjusted by changing the size of the gap 9d.

To reduce the weight of the panel 1, the amount of first adhesive 6a used must be minimized. However, under these constraints, spray coaters reduce the uniformity of application of the first adhesive 6a, resulting in greater in-plane variation in adhesive strength and making the face material 3 more susceptible to peeling in areas with weak adhesive strength. On the other hand, roll coaters have the advantage of making it easier to achieve high application uniformity even when the amount of first adhesive 6a used is reduced.

Furthermore, the substrate 2 may have an uneven surface. Applying an adhesive to such a surface using a roll coater results in variations in the thickness of the applied first adhesive 6a, resulting in greater in-plane variation in adhesive strength and making the face material 3 more susceptible to peeling in areas with weak adhesive strength. On the other hand, the surface unevenness of the face material 3 is smaller than that of the substrate 2, so applying the first adhesive 6a to the face material 3 reduces variation in the applied thickness of the first adhesive 6a compared to applying the first adhesive 6a to the substrate 2. Furthermore, when the substrate 2 is a bead foam molded body, the surface unevenness of the substrate 2 is particularly pronounced, making the application of the first adhesive 6a to the face material 3 particularly significant.

Examples of the first adhesive 6a include polyurethane adhesives and polyolefin adhesives. The first adhesive 6a is preferably moisture-curing and can be melted by heating (a hot-melt adhesive). In this case, the face material 3 is temporarily bonded to the substrate 2 while the adhesive is heated, and then the full bond can be achieved by moisture curing. After full bonding, the adhesive does not melt even when heated, improving the high-temperature resistance of the panel 1. For these reasons, the first adhesive 6a is preferably a moisture-curing hot-melt adhesive, and even more preferably a moisture-curing polyurethane-based hot-melt adhesive. This is because moisture-curing polyurethane-based hot-melt adhesives have excellent roll coater suitability. The amount of the first adhesive 6a used is, for example, 10 to 100 g/ ^m² , specifically, for example, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 g/ ^m² , and may be within a range between any two of the values exemplified here.

(1-2) First Attachment Step In the first attachment step, the surface of the face material 3 on which the first adhesive 6a is applied is attached to the substrate 2 to form the bonded body 8 shown in FIG. 1C. This step can be performed by pressing the face material 3 against the substrate 2 with the surface of the face material 3 on which the first adhesive 6a is applied facing the substrate 2. An adhesive layer 6 is formed by the first adhesive 6a. When the face material 3 is attached to both sides of the substrate 2, the face materials 3 on both sides may be attached to the substrate 2 simultaneously, or may be attached one side at a time in sequence.

When manufacturing a panel 1 configured with a face material 3 disposed within a recess 5 in a base material 2, the face material 3 may be disposed within a recess 5 previously formed in the base material 2, or the face material 3 may be pressed against the base material 2 to sink the face material 3 into the base material 2 and form the recess 5.

It is preferable to include a heating step between the first application step and the first attachment step. In the heating step, the first adhesive 6a applied to the face material 3 is heated. By including this step, it is possible to suppress a decrease in adhesive strength that occurs as the temperature of the first adhesive applied to the face material 3 decreases.

(2) Second Adhesion Step In the second adhesion step, the skin material 4 is adhered to the adhesive body 8 to form the panel 1. The second adhesion step includes a second application step and a second attachment step.

(2-1) Second Coating Step As shown in FIG. 4, in the second coating step, a second adhesive 7 a is applied to the skin material 4 by a spray coater 10 .

The spray coater 10 is a coating device that uses a spray head 10a. The adhesive is applied to the object by spraying it from the spray head 10a onto the object.

In one example, the spray coater 10 includes a spray head 10a and a drive unit 10b. The drive unit 10b is, for example, a robot arm 10b1. The spray head 10a is attached to the drive unit 10b and is driven by the drive unit 10b to apply a desired amount of adhesive to a desired area on the workpiece.

To reduce the weight of the panel 1, the amount of second adhesive 7a used must be minimized. Furthermore, to prevent peeling of the skin 4, the adhesive strength of the peripheral edge of the skin 4 must be increased. With a roll coater, the amount of adhesive applied to the peripheral edge of the skin 4 cannot be greater than that applied to the center (areas other than the peripheral edge) of the skin 4. Therefore, if there are limitations on the amount of second adhesive 7a used, the amount of adhesive applied to the peripheral edge of the skin 4 may be insufficient, resulting in insufficient adhesive strength at the peripheral edge of the skin 4. On the other hand, with a spray coater, it is possible to apply any amount of adhesive to any location on the skin 4. Therefore, by reducing the amount of adhesive applied to the center of the skin 4, the amount of adhesive applied to the peripheral edge of the skin 4 can be increased without changing the amount of adhesive used, thereby increasing the adhesive strength at the peripheral edge of the skin 4.

While it is possible to apply the second adhesive 7a to the adhesive body 8, applying the second adhesive 7a to both the main surface 8a and the side surface 8c of the adhesive body 8 requires complicated movement of the spray head 10a. In addition, applying the second adhesive 7a to the main surface 8b of the adhesive body 8 also requires turning the adhesive body 8 over, which increases the time required for the second application step. For this reason, it is preferable to apply the second adhesive 7a to the covering material 4.

Examples of the second adhesive 7a include polyurethane adhesives and polyolefin adhesives. Furthermore, the second adhesive 7a is preferably moisture-curing and can be melted by heating (a hot-melt adhesive). In this case, the skin material 4 is temporarily bonded to the adhesive body 8 while the adhesive is heated, and then the full bond can be achieved by moisture curing. After full bonding, the adhesive does not melt even when heated, improving the high-temperature resistance of the panel 1. For these reasons, it is particularly preferable that the second adhesive 7a be a moisture-curing hot-melt adhesive.

Furthermore, when the second adhesive 7a applied to the covering material 4 is attached to the adhesive body 8 without heating, a moisture-curing polyolefin-based hot melt adhesive tends to have higher adhesive strength than a moisture-curing polyurethane-based hot melt adhesive, so the second adhesive 7a is preferably a moisture-curing polyolefin-based hot melt adhesive. When the second adhesive 7a is a moisture-curing polyurethane-based hot melt adhesive, it is preferable to include a heating step between the second application step and the second attachment step, in which the second adhesive 7a applied to the covering material 4 is heated.

The amount of the second adhesive 7a used is, for example, 10 to 100 g/ ^m2 , specifically, for example, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 g/ ^m2 , and may be within a range between any two of the numerical values exemplified here.

(2-2) Second Attachment Step In the second attachment step, the surface of the skin 4 on which the second adhesive 7a is applied is attached to the adhesive body 8. This step can be performed by pressing the skin 4 against the adhesive body 8 with the surface of the skin 4 on which the second adhesive 7a is applied facing the adhesive body 8. The adhesive layer 7 is formed by the second adhesive 7a. When the skin 4 includes skins 4a and 4b, the skin 4b can be attached after the skin 4a is attached. It is preferable to attach the skin 4b so that the peripheral edge of the skin 4b overlaps the peripheral edge of the skin 4a.

1. Manufacturing of Panel 1 Panel 1 was manufactured under the conditions shown in Table 1 according to the manufacturing method described in the above embodiment. The roll coater used was a roll coater 9 (hot melt roll coater) shown in Figure 3. The spray coater used was a spray coater 10 shown in Figure 4. Details of the members used in the manufacturing are as follows:
Substrate 2: Bead expansion molding formed using Heat Pole GR (JSP Corporation, expandable polyacrylonitrile/styrene beads), expansion ratio 40 times, thickness 20 mm, 1000 mm x 450 mm
Surface material 3: Surface material made of Al (Al5052), thickness 0.3 mm, 990 mm x 440 mm
Skin materials 4a and 4b: Skin materials made of nonwoven fabric (PET, skin material 4a: 300 g/m ² , skin material 4b: 100 g/m ² ), skin material 4a is 1120 mm x 570 mm, skin material 4b is 960 mm x 410 mm.
Polyurethane adhesive: Moisture-curing polyurethane hot melt adhesive (Henkel TECHNOMELT PUR 3460)
Polyolefin adhesive: Moisture-curing polyolefin hot melt adhesive (Moresco Melt RO-1280)
Roll coater 9: effective roll width 620 mm, coating roll diameter 140 mm, doctor roll diameter 80 mm, coating speed 7 m/min. Spray coater 10: 216 nozzles with a nozzle diameter of 0.3 mm x 0.4 mm arranged in a straight line at 0.5 mm pitch.

The amount of the first adhesive 6a used in the first bonding step was 60 g/ ^m2 , and the amount of the second adhesive 7a used in the second bonding step was 60 g/ ^m2 . When the second adhesive 7a was applied by the spray coater 10 in the second bonding step, the amount of the second adhesive 7a applied in the region 30 mm from the periphery of the skin material 4 was three times that of the other region.

In the first bonding step, the first adhesive 6a was applied at 120°C. In the first and second bonding steps, the heating step was performed so that the adhesive temperature was 80°C. When heating was not performed in the first bonding step, the face material 3 was attached to the substrate 2 approximately 10 seconds after application of the first adhesive 6a. When heating was performed in the first bonding step, the face material 3 was attached to the substrate 2 approximately 30 seconds after application of the first adhesive 6a. When heating was not performed in the second bonding step, the skin material 4 was attached to the adhesive body 8 approximately 20 seconds after application of the second adhesive 7a. When heating was performed in the second bonding step, the skin material 4 was attached to the adhesive body 8 approximately 40 seconds after application of the second adhesive 7a.

In the second adhesion process, after attaching the skin material 4a, the skin material 4b was attached so that the peripheral edges of the skin materials 4a and 4b overlapped by 10 mm.

2. Evaluation Evaluation was carried out by the following methods, and the results are shown in Table 1.

<Adhesive strength of surface material>
At each of nine points evenly arranged in a grid pattern on the panel 1, a 25 mm x 150 mm test piece was cut out, the face material was peeled off about 20 mm from the edge of the test piece, and the peeled face material was chucked while the substrate was fixed and peeled off at a tensile speed of 200 mm/min using a tensile tester. The peel strength when the face material 3 was peeled off from the substrate 2 in this manner was measured, and the test piece with the lowest peel strength among the nine test pieces was evaluated according to the following criteria.
◯: Peel strength is 10 N or more.
Δ: Peel strength is 5N or more and less than 10N.
×: Peel strength is less than 5N.

<Application speed of second adhesive>
The coating time from the start to the end of coating of the second adhesive 7a was measured and evaluated according to the following criteria.
Good: The coating time was 10 seconds or less.
△: Coating time is more than 10 seconds and 30 seconds or less.
×: Coating time exceeds 30 seconds.

<Edge adhesive strength of skin material>
Test pieces measuring 25 mm × 150 mm were cut out from panel 1 at 10 locations on the periphery of skin material 4a (two locations on each of the short sides and three locations on each of the long sides of panel 1), and the skin material was peeled off by approximately 20 mm from the edge of the test piece. With the adhesive still fixed, the peeled skin material was chucked and peeled off at a tensile speed of 200 mm/min using a tensile tester. The peel strength when skin material 4a was peeled off from adhesive body 8 was measured, and the test piece with the lowest peel strength among the 10 test pieces was used to evaluate the test piece according to the following criteria.
◯: Peel strength is 7N or more.
Δ: Peel strength is 3N or more and less than 7N.
×: Peel strength is less than 3N.

1: Panel 2: Base material 2a: First main surface 2b: Second main surface 2c: Side surface 3: Face material 4: Skin material 4a: First skin material 4b: Second skin material 5: Recess 6: Adhesive layer 6a: First adhesive 6b: Thin film 6c: Coating film 7: Adhesive layer 7a: Second adhesive 8: Adhesive body 8a: First main surface 8b: Second main surface 8c: Side surface 9: Roll coater 9a: Coating roll 9b: Doctor roll 9c: Backup roll 9d: Gap 9e: Gap 10: Spray coater 10a: Spray head 10b: Drive unit 10b1: Robot arm

Claims (4)

A method for manufacturing a panel, comprising a first bonding step and a second bonding step,
In the first bonding step, a face material is bonded to a plate-shaped substrate to form a bonded body;
In the second bonding step, a skin material is bonded to the bonded body to form a panel;
The first bonding step includes a first application step and a first attachment step,
In the first application step, a first adhesive is applied to the face material by a roll coater;
In the first bonding step, the surface of the face material to which the first adhesive is applied is bonded to the base material to form the bonded body;
The second adhesion step includes a second application step and a second attachment step,
In a second application step, a second adhesive is applied to the skin material using a spray coater;
In the second attaching step, the surface of the skin material to which the first adhesive is applied is attached to the adhesive body;
In the second attaching step, the skin material is attached so as to cover at least a portion of the first main surface of the adhered body, at least a portion of the side surface of the adhered body , and at least a portion of the second main surface of the adhered body. 10. The method of claim 1,
A heating step is provided between the first application step and the first attachment step,
In the heating step, the first adhesive applied to the face material is heated. 3. The method of claim 1 or claim 2,
The method wherein the first adhesive is a moisture-curable polyurethane-based hot melt adhesive. The method according to any one of claims 1 to 3,
The method wherein the second adhesive is a moisture-curable polyolefin-based hot melt adhesive.