JP2018034391A - Foamed body, resin-made panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable reinforcing a desired position of a resin-made panel without receiving limitations of a shape or use environment of a resin-made panel.SOLUTION: The foamed body is a tabular foamed body. The foamed body has a first foaming area with first foaming ratio and a second foaming area with a second foaming ratio which is lower than the first foaming ratio. The second foaming area is at least partially formed along circumference of the foamed body or formed with crossing from one part to another part of the circumference of the foamed body.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a foam and a resin panel.

  Conventionally, resin panels in which a foam as an interior material is covered with a skin material sheet have been used for various purposes such as automobiles, building materials, sports and leisure. Moreover, in order to locally reinforce a resin panel, it is known that a reinforcing material (reinforce) is interposed between two foamed portions constituting the interior material (for example, cited document 1).

Japanese Patent Laying-Open No. 2015-164863

The reinforcing material is generally made of metal, but the metal reinforcing material may not be used at a desired position depending on the shape of the resin panel and the usage environment.
From this point of view, an object of the present disclosure is to allow a desired position of the resin panel to be reinforced without being restricted by the shape of the resin panel and the use environment.

A first aspect of the present disclosure is a plate-like foam,
A first foaming region composed of a first foaming ratio, and a second foaming region composed of a second foaming ratio lower than the first foaming ratio,
The second foam region is formed at least partially along the periphery of the foam, or is formed so as to cross from a part of the periphery of the foam to another part. And

  In the foam, the thickness of the cross section of the second foam region may not be uniform.

  In the foam, a hinge may be formed in at least a part of the second foam region.

  The said foam WHEREIN: The 1st foaming part which has the said 1st foaming area | region, and the 2nd foaming part which has the said 2nd foaming area | region may be connected.

  In the foam, in the connection region where the first foam part and the second foam part are connected, both the first foam part and the second foam part are the front of the foam. You may have a part which penetrates between a surface and a back surface.

  The 2nd viewpoint of this indication is a resin panel which covered the foam mentioned above with the skin material sheet.

  The desired position of the resin panel can be reinforced without being restricted by the shape of the resin panel and the usage environment.

The perspective view of the resin-made panels of embodiment, and the one part expanded fracture view. The perspective view of the interior material currently equipped with the resin-made panels of embodiment. The figure explaining the method of forming the interior material of embodiment by several foaming parts. The figure explaining the process of shape | molding the skin material of the resin-made panels of embodiment. The figure explaining the process of shape | molding the skin material of the resin-made panels of embodiment. The top view which shows the usage example of the resin-made panels of embodiment. The figure which shows the interior material which concerns on the modification of embodiment. The figure which shows the interior material which concerns on the modification of embodiment. The figure which shows the interior material which concerns on the modification of embodiment. The figure which shows the interior material which concerns on the modification of embodiment. The figure which shows the interior material which concerns on the modification of embodiment. The figure which shows the interior material which concerns on the modification of embodiment. The figure which illustrates the connection method of two foaming parts. The figure which illustrates the connection method of two foaming parts. The figure which illustrates the connection method of two foaming parts. The figure which illustrates the connection method of two foaming parts. The figure which illustrates the connection method of two foaming parts. The figure which illustrates the connection method of two foaming parts. The top view of the interior material which concerns on an Example. The top view of the interior material which concerns on a comparative example.

  Hereinafter, the resin panel 1 which is one embodiment of the present invention and the interior material 2 for the resin panel 1 will be described. The interior material 2 for the resin panel 1 is an example of the foam of the present invention and is a core material of the resin panel 1.

(1) Resin panel 1 and interior material 2 for resin panel 1
First, with reference to FIG.1 and FIG.2, the structure of the resin panels 1 and the interior material 2 of this embodiment is demonstrated. FIG. 1 is a perspective view of a resin panel 1 of the present embodiment and an enlarged cutaway view of a part thereof. FIG. 2 is a perspective view of the interior material 2 of the present embodiment.

  As shown in FIG. 1, the outer shape of the resin panel 1 according to the embodiment includes a front surface 1a, a back surface 1b, and a long side wall surface 1c interposed between the front surface 1a and the back surface 1b. It is a substantially rectangular parallelepiped shape composed of the short side wall surface 1d. The front surface 1a, the back surface 1b, the long side wall surface 1c, and the short side wall surface 1d are constituted by a skin material sheet S made of thermoplastic resin, and an interior material 2 is provided therein. Yes. That is, the resin panel 1 has a structure in which the interior material 2 is covered with the skin sheet S of the thermoplastic resin.

  In the resin panel 1 of the embodiment, the skin material sheet S serving as the skin material sheet is not limited to the resin material, but is preferably formed from a non-foamed resin in order to ensure the rigidity of the resin panel 1. For example, in consideration of moldability, the skin material sheet S may be obtained by mixing polystyrene (PS) and styrene ethylene butylene styrene block copolymer resin (SEBS) with polypropylene (PP) as a main material.

  As shown in FIG. 2, the interior material 2 is a composite structure in which the foamed portions 21 to 23 are connected and integrated. The shape of the foamed portions 21 to 23 may be determined as appropriate according to the appearance and usage environment required for the resin panel 1, and is not particularly limited.

  In the resin panel 1 of the embodiment, the foamed portions 21 to 23 are formed using, for example, a thermoplastic resin. The resin material is not limited, but includes any one of polyolefins such as polypropylene and polyethylene, acrylic derivatives such as polyamide, polystyrene, and polyvinyl chloride, or a mixture of two or more.

  In the resin panel 1 of the embodiment, examples of the foaming agent that can be used for the foamed portions 21 to 23 include known physical foaming agents, chemical foaming agents, and mixtures thereof. For example, as the physical foaming agent, inorganic physical foaming agents such as air, carbon dioxide gas and nitrogen gas, and organic physical foaming agents such as butane, pentane, hexane, dichloromethane and dichloroethane can be applied. Examples of the chemical foaming agent include azodicarbonamide (ADCA), N, N′-dinitrosopentamethylenetetramine, 4,4′-oxybis (benzenesulfonylhydrazide), diphenylsulfone-3,3′-disulfonyl. Organic blowing agents such as hydrazide, p-toluenesulfonyl semicarbazide, trihydrazinotriazine or azobisisobutyronitrile, citric acid, oxalic acid, fumaric acid, phthalic acid, malic acid, tartaric acid, cyclohexane-1,2-dicarboxylic acid , A mixture of polycarboxylic acids such as camphoric acid, ethylenediaminetetraacetic acid, triethylenetetraminehexaacetic acid, nitrilolic acid and inorganic carbonic acid compounds such as sodium bicarbonate, sodium aluminum bicarbonate, potassium bicarbonate, ammonium bicarbonate, ammonium carbonate Citric dihydrogen sodium hydrogen salts of polycarboxylic acids, such as potassium oxalate and the like as the inorganic foaming agent.

  If a foam having a low expansion ratio is used as the overall interior material of the resin panel 1, it is not preferable in that the required weight can be ensured but the overall weight increases. Therefore, in the interior material 2 of the present embodiment, a foamed portion with a low expansion ratio is applied to a portion that requires reinforcement (for example, a portion having the lowest rigidity), and foaming with a high expansion ratio is applied to a portion that does not require much reinforcement. By applying the part, there is a feature in that the rigidity is locally increased while suppressing the overall weight.

In the example shown in FIG. 2, it is assumed that reinforcement is required in the vicinity of the short side wall surface 1 d of the resin panel 1. Therefore, the foaming ratio of the foaming part 21 and the foaming part 23 corresponding to the vicinity of the short side wall surface 1d is relatively low, and the foaming ratio of the foaming part 22 between the foaming part 21 and the foaming part 23 is relatively low. To be high.
In the present embodiment, the foam portion 22 is an example of a first foam region of the interior material 2. The foamed portions 21 and 23 are an example of a second foaming region of the interior material 2 and are partially formed along the periphery of the interior material 2.

  As illustrated in FIG. 2, when the interior material 2 is configured by two or more foamed portions having different foaming ratios, the foaming ratio of each foamed part is not particularly limited. Is 30 to 40 times, and a relatively low expansion ratio is 10 to 20 times. The expansion ratio is a value obtained by dividing the density of the mixed resin before foaming by the apparent density of the foamed resin after foaming.

The skin material sheet S and the foamed portions 21 to 23 may be molded using a resin material mixed with a glass filler for the purpose of increasing rigidity and strength.
Examples of the glass filler include glass fiber, glass fiber cloth such as glass cloth and glass nonwoven fabric, glass beads, glass flakes, glass powder, and milled glass. Examples of the glass include E glass, C glass, A glass, S glass, D glass, NE glass, T glass, quartz, low dielectric constant glass, and high dielectric constant glass.
In addition to the glass filler, inorganic fillers such as talc, calcium carbonate, wollastonite, magnesium-based material, and the like for increasing rigidity may be mixed.

(2) Method for Assembling Interior Material 2 A method for assembling the interior material 2 will be described with reference to FIG. FIG. 3 is a diagram for explaining a method of forming the interior material 2 of the embodiment by a plurality of foamed portions, and shows a method of connecting the foamed portion 21 and the foamed portion 22 as an example.
In order to assemble the interior material 2 of the present embodiment, first, the foamed portions 21 and 23 having a low expansion ratio and the foamed portion 22 having a high expansion ratio are separately formed. In the example shown in FIG. 3A, the end portion that becomes the boundary between the foamed portion 21 and the foamed portion 22 is a U-shaped groove and a U-shaped projection. After forming the foamed portions 21 to 23, foaming is performed by engaging a U-shaped groove and a U-shaped protrusion at the ends of the foamed portion 21 and the foamed portion 22 as shown in FIG. The part 21 and the foaming part 22 are connected. Although not shown, the foamed portion 22 and the foamed portion 23 are connected to each other by engaging the U-shaped groove and the U-shaped protrusion at the end of each foamed portion. In FIG. 3B, the connection region H indicates a region where a foaming portion having a low expansion ratio and a foaming portion having a high expansion ratio are mixed.
The foamed portions 21 to 23 are formed by, for example, a bead method in-mold foam molding method. For a molding example by the bead method in-mold foam molding method, refer to, for example, Japanese Patent Application Laid-Open No. 2014-128938.

(3) Molding method of resin panel 1 Next, with reference to FIG.4 and FIG.5, the method to shape | mold the resin panel 1 of embodiment using a metal mold | die is demonstrated. 4 and 5 are diagrams for explaining a process of molding the skin sheet S of the resin panel 1 of the present embodiment.

  Referring to FIG. 4, the mold clamping device 70 is positioned between the open position and the closed position in a direction substantially orthogonal to the molten resin sheets P and P extruded vertically from an extrusion device (not shown). It has a pair of split molds 71A and 71B to be moved. The pair of split molds 71A and 71B are arranged in a state where the formation surfaces 72A and 72B corresponding to each of them are opposed to each other. The formation surface 72A has a shape corresponding to the front surface and the back surface of the interior material 2.

  In each of the pair of split molds 71A and 71B, pinch-off portions 74A and 74B are formed in the vicinity of upper and lower ends of the corresponding formation surfaces 72A and 72B. The pinch-off portions 74A and 74B are formed annularly around the formation surfaces 72A and 72B, respectively, and project toward the opposing split molds 71B and 71A. As a result, when clamping the pair of split molds 71A and 71B, the tip portions of the pinch-off portions 74A and 74B come into contact with each other, and a parting line is formed at the periphery of the molten resin sheets P and P. ing.

  The pair of split molds 71A and 71B are provided with sliding portions 75A and 75B that can protrude from the formation surfaces 72A and 72B around the formation surfaces 72A and 72B. The sliding portions 75A and 75B are in a state of projecting from the formation surfaces 72A and 72B, and their end surfaces are brought into contact with the molten resin sheets P and P, whereby the molten resin sheets P and P and the pair of split molds 71A and 71B It is provided to form a sealed space between the formation surfaces 72A and 72B.

  The pair of split molds 71A and 71B includes a vacuum chamber (not shown). The vacuum chamber is connected to a vacuum pump and a vacuum tank (both not shown). A communication path (not shown) for vacuum suction is provided between the vacuum chamber and the formation surfaces 72A and 72B.

  The pair of split molds 71A and 71B are driven by a mold driving device (not shown) so as to be movable between an open position and a closed position. In the open position, two continuous molten resin sheets P, P can be arranged at a distance from each other between the pair of split molds 71A, 71B. The two molten resin sheets P and P become the skin material sheet S in the resin panel 1 after molding. In the closed position, the pinch-off portions 74A and 74B of the pair of split molds 71A and 71B abut.

Next, a method for forming the resin panel 1 will be described.
First, as shown in FIG. 4, the molten resin sheets P and P are extruded vertically downward from the extrusion device and supplied between the forming surfaces 72A and 72B of the pair of split molds 71A and 71B. At this point, the pair of split molds 71A and 71B are in the open position.

  Next, the sliding portions 75A and 75B around the formation surfaces 72A and 72B are protruded, and the end surfaces thereof are brought into contact with the molten resin sheets P and P. As a result, a sealed space is formed between the molten resin sheets P and P and the formation surfaces 72A and 72B of the pair of split molds 71A and 71B. And the air in sealed space is attracted | sucked by the communicating path provided between the vacuum chamber and formation surface 72A, 72B. By this suction, the two molten resin sheets P and P are pressed against the formation surfaces 72A and 72B of the pair of split molds 71A and 71B, respectively, and along the formation surfaces 72A and 72B as shown in FIG. It is shaped (formed) into the shape, that is, the substantially outer shape of the resin panel 1.

  Next, the interior material 2 assembled as described above is positioned between the pair of split molds 71A and 71B using a manipulator (not shown), and as shown in FIG. It inserts so that it may press against a division mold (in FIG. 5, division mold 71B). Thereby, the interior material 2 is welded to one molten resin sheet P.

  Thereafter, the pair of split molds 71A and 71B are moved from the open position to the closed position and clamped. Thereby, the interior material 2 welded to one molten resin sheet P (right side of the drawing) is also welded to the other molten resin sheet P (left side of the drawing). Furthermore, in the pinch-off portions 74A and 74B of the pair of split molds 71A and 71B, the peripheral edges of the pair of molten resin sheets P and P are welded to form the parting line PL.

Finally, the pair of split molds 71A and 71B are moved again to the open position, the molded resin panel 1 is separated from the formation surfaces 72A and 72B, and the burrs formed around the parting line PL are removed with a cutter or the like. Cut and remove. Thus, the resin panel 1 having a structure in which the interior material 2 is covered with the skin sheet S is completed.
In the method for molding the resin panel 1 described above, the case where the molten resin sheet P is pressed against the formation surfaces 72A and 72B of the pair of split molds 71A and 71B by suction has been described, but the present invention is not limited thereto. The molten resin sheet P may be pressed against the formation surfaces 72A and 72B of the pair of split molds 71A and 71B by blowing a fluid such as air onto the molten resin sheet P (blow molding).

  As described above, according to the resin panel 1 of the present embodiment, the interior material 2 is configured by combining the foamed portion with a low foaming ratio and the foamed portion with a high foaming ratio. It is possible to suppress the overall weight while ensuring a sufficient rigidity.

In FIG. 6, the usage example of the resin panels 1 of this embodiment is shown. In FIG. 6, it has shown by the state (namely, interior material 2) which removed the skin material sheet | seat S from the resin-made panels 1 so that the connection state of a some foaming part can be understood. In FIG. 6, the resin panel 1 is used by being placed on the stand ST, but a use example is assumed in which the area of the resin panel 1 in contact with the stand ST is small. In such a use example, even if a reinforcing material (reinforce) is to be incorporated along the short side wall surface 2d of the interior material, the resin panel cannot be effectively reinforced. The reason is that if the end of the reinforcing material is too close to the skin material sheet S, the skin material sheet S may be damaged, and therefore both ends of the reinforcing material may be arranged up to the long side wall surface 2c of the interior material. This is because it cannot be done.
On the other hand, the interior material 2 of the resin panel 1 of the present embodiment has the foam portions 21 and 23 having a relatively high rigidity and a low expansion ratio formed over the entire short side wall surface 2d. Even when the area of the resin panel 1 in contact with the ST is small, the resin panel 1 can be locally reinforced.

(4) Modified Example of Resin Panel Next, a resin panel according to a modified example will be described with reference to FIGS. 7-12 is a figure which shows the interior material respectively equipped with the resin-made panels which concern on the modification of embodiment. In each figure, it shows by the state (namely, interior material) which removed the skin material sheet | seat from the resin-made panels so that the engagement state of a some foaming part can be understood.

(4-1) First Modification FIG. 7A is a plan view of an interior material 2A according to a first modification and a table ST on which the interior material 2A is placed. 7B and 7C show examples of the AA cross section of FIG. 7A, respectively.
As shown in FIG. 7A, the interior material 2A according to the first modified example connects the foamed portions 21A, 23A having a low foaming ratio and the foamed portion 22A having a high foaming ratio in the same manner as the interior material 2. Is formed. As illustrated in FIGS. 7B and 7C, the interior material 2A according to the first modified example is a general-purpose material having a uniform cross-sectional shape because the interior material 2A has a non-uniform cross section. Reinforcing material cannot be used. In particular, in the case of FIG. 7C, since the end of the interior material 2A is thin, it is even more difficult to use a reinforcing material.
However, since the interior material 2A according to the first modification includes the foamed portions 21A and 23A having relatively high rigidity and low expansion ratio, the rigidity of the interior material 2A is locally increased without using a reinforcing material. Can do.
In addition, when a resin panel having a dent in the center as shown in FIG. 7B is used for a rear parcel shelf of a vehicle, a seat is provided in the dent to protect the occupant during a rear-end collision of the vehicle. It is required to bend (that is, to have an impact absorbing effect). Here, if a general-purpose reinforcing material (reinforce) is used instead of the foamed portions 21A and 23A, the reinforcing material does not break properly at the time of a collision, and an unfavorable situation may occur for passenger protection. On the other hand, in this modification, since it is easy to buckle in the central recess, there is an advantage that it is easy to exhibit the impact absorbing effect while ensuring local rigidity.

(4-2) Second Modification FIG. 8 is a plan view of an interior material 2B according to a second modification and a table ST on which the interior material 2B is placed.
As shown in FIG. 8, the interior material 2B according to the second modification is placed on the table ST at the left and right ends, and connects the foam portion 21B having a low foaming ratio and the foam portion 22B having a high foaming ratio. Is formed. The foamed portion 21B of the interior material 2B has an overall curved shape across the left and right ends on the lower side in the drawing. In the case of such a curved shape, a general-purpose reinforcing material having a uniform cross-sectional shape cannot be used even if the thickness is uniform. However, in the interior material 2B according to the second modification, since the foaming ratio of the foamed portion 21B is lowered, the rigidity of the curved shape portion can be locally increased without using a reinforcing material.

(4-3) Third Modification FIG. 9 is a plan view of an interior material 2C according to a third modification and a table ST on which the interior material 2C is placed.
As shown in FIG. 9, the interior material 2B according to the third modification is placed on the table ST at the left and right ends, and connects the foam portion 21C having a low foaming ratio and the foam portion 22C having a high foaming ratio. Is formed. Since the handle 21Ch is attached to the foamed portion 21C of the interior material 2C, the cross-sectional shape of the foamed portion 21C is not uniform, so that a general-purpose reinforcing material having a uniform cross-sectional shape may be used. Can not. However, in the interior material 2C according to the third modification, the foaming ratio of the foamed portion 21C is lowered, so that the rigidity of the interior material 2C can be locally increased even when the handle 21Ch is provided.

(4-4) Fourth Modification FIG. 10 is a plan view of an interior material 2D according to a fourth modification and a table ST on which the interior material 2D is placed.
In the interior material 2 according to the above-described embodiment and the interior materials 2A to 2C according to the first to third modifications, a description is given of a case where a foam portion having a high rigidity and a low foaming ratio is disposed along the periphery of the interior material. However, this is not the case. In the fourth modification, the foaming portion having a low foaming ratio is formed so as to cross from a part of the periphery of the interior material to another part.
The interior material 2D according to the fourth modification shown in FIG. 10 is placed on the table ST over the entire periphery. The interior material 2D is formed by connecting the foamed portions 21D and 23D with high foaming ratio and the foamed portion 22D with low foaming ratio. The foam portion 22D having high rigidity and low foaming ratio is formed between a pair of opposed long side wall surfaces 2c in the central portion of the interior material 2D.

(4-5) Fifth Modification FIG. 11A is a plan view of an interior material 2E according to a fifth modification and a table ST on which the interior material 2E is placed. FIG.11 (b) is BB expanded sectional drawing of Fig.11 (a).
In the interior material 2 of the above-described embodiment and the interior materials 2A to 2D according to the first to fourth modifications described above, the case where a foaming portion having a low foaming ratio is applied instead of the reinforcing material has been described. A reinforcing material can be used in addition to the foamed portion of magnification. The interior material 2E according to the fifth modified example is different from the interior material 2D according to the fourth modified example in that the reinforcing material 3 is disposed between the pair of opposing short side wall surfaces 2d.
As shown in FIG. 11B, the reinforcing material 3 is a reinforcement having a H-shaped cross section. As the reinforcing material 3 is disposed, the interior material 2E is formed by connecting the foamed portions 21E, 22E, 23E, and 24E with high foaming ratio and the foamed portions 25E and 26E with low foaming ratio. The foamed portion 25E is fitted from one side of the reinforcing material 3, and the foamed portion 26E is fitted from the other side of the reinforcing material 3.

(4-6) Sixth Modification FIG. 12 is a perspective view of an interior material 2F according to a sixth modification.
The interior material 2F shown in FIG. 12 is formed by connecting low foaming ratio foamed parts 21F, 23F and a high foaming ratio foamed part 22F. In the interior material 2F, a hinge HG is formed across the pair of long side wall surfaces 2c. As shown in FIG. 12, when the hinge HG is formed in at least a part of the foamed portions 21F and 23F, if the reinforcing material is incorporated in the position where the foamed portions 21F and 23F are provided, the hinge function is achieved. In order to ensure, the end part of the reinforcing material in the extending direction must be separated from the hinge HG, and it is difficult to reinforce the vicinity of the hinge HG. On the other hand, the interior material 2F of the present modification employs the foamed portions 21F and 23F having relatively high rigidity and low expansion ratio in the vicinity of the hinge HG, so that the vicinity of the hinge HG can be reinforced. .

(5) Modified Example of Method for Connecting Two Adjacent Foamed Parts In the above-described embodiment, foaming is performed by engaging a U-shaped groove and a U-shaped protrusion at the ends of the foamed part 21 and the foamed part 22. Although the connection method which connects the part 21 and the foaming part 22 was illustrated, it is not the limitation of the connection method of foaming parts.
Below, with reference to FIGS. 13-18, the modification of the method of connecting two foaming parts which adjoin in an interior material is demonstrated. 13, 14, and 16 to 18 are perspective views illustrating a method of connecting the first foamed portion J1 and the second foamed portion J2, respectively. FIGS. 13, 14, and 16 to 18 (a) show a state before connection, and FIGS. 13, 14, and 16 to 18 (b) show a state after connection. 13, 14, and 16 to 18 (b), the connection region H between the foamed portions is shown. FIG. 15A is a plan view of the modification shown in FIG. FIGS. 15B and 15C are enlarged sectional views taken along lines CC and DD in FIG. 15A, respectively.

(5-1) First Modification The connection method of the first modification shown in FIG. 13 is that the trapezoidal groove and the trapezoidal protrusion are engaged with each other, so that the first foaming part J1 and the second modification are engaged. This is a method of connecting the foamed portions J2. In this connection method, the trapezoidal grooves and the trapezoidal protrusions of the first foaming portion J1 and the second foaming portion J2 are engaged with each other in the vertical direction. The connection method of the present modification is effective in that the relative movement in the lateral direction of the first foaming portion J1 and the second foaming portion J2 is restricted after being engaged once.

(5-2) Second Modification In the connection method according to the second modification shown in FIG. 14, holes J1h and protrusions J1p are alternately formed in the first foam part J1, and the second foam part. Holes J2h and protrusions J2p are alternately formed in J2. The hole J1h of the first foam part J1 and the protrusion J2p of the second foam part J2 are engaged, and the protrusion J1p of the first foam part J1 and the hole J2h of the second foam part J2 are engaged in the vertical direction. Thereby, the 1st foaming part J1 and the 2nd foaming part J2 are connected. The plate thickness in the connection region H of the first foamed part J1 and the second foamed part J2 is set so that the desired plate thickness is obtained in the connection region H. Note that the number of holes and protrusions in each foamed portion can be arbitrarily selected.

As shown in FIGS. 15B and 15C, in the connection method according to this modification, in the connection region H, both the first foamed portion J1 and the second foamed portion J2 are made of interior material. It has a portion (penetrating portion) that penetrates between the front surface and the back surface at the shortest distance. When the skin material is formed on the interior material, the penetration portion is welded to the molten resin sheet serving as the skin material on both the front surface and the back surface of the interior material. There exists an effect that the connection force of the foaming part J1 and the 2nd foaming part J2 becomes high.
In the connection method (FIG. 3) of the embodiment described above and the connection method (FIG. 13) according to the first modification, both the first foamed portion J1 and the second foamed portion J2 are connected in the connection region H. Since the interior material has a portion that penetrates between the front surface and the back surface at the shortest distance, there is an effect that the coupling force is also high.

(5-3) Third Modification In the connection method according to the third modification shown in FIG. 16, the protrusion J1p is formed in the first foaming portion J1, and the hole J2h is formed in the second foaming portion J2. Is formed. The first foamed part J1 and the second foamed part J2 are connected by engaging the protrusion J1p of the first foamed part J1 with the hole J2h of the second foamed part J2. The plate thickness in the connection region H of the first foamed part J1 and the second foamed part J2 is set so that the desired plate thickness is obtained in the connection region H. Note that the number of protrusions J1p of the first foaming portion J1 and the number of holes J2h of the second foaming portion J2 can be arbitrarily selected.

(5-4) Fourth Modified Example In the connection method according to the fourth modified example shown in FIG. 17, a U-shaped groove and a U-shaped end portion of the first foamed part J1 and the second foamed part J2. 3 is the same as the example shown in FIG. 3 except that the U-shaped groove and the U-shaped projection pattern are complementary on the front and back sides. Is different from the example shown in FIG. Also in this modified example, similarly to FIG. 3, the U-shaped groove and the U-shaped protrusion of the first foamed portion J1 and the first foamed portion J1 are engaged, and the connection region H is provided.

(5-5) Fifth Modification In the connection method according to the fifth modification shown in FIG. 18, compared to the second modification (FIG. 14) and the third modification (FIG. 16), the holes And there is no protrusion. In this modification, since the first foaming part J1 and the second foaming part J2 are easy to move relative to each other, it is preferable to bond the first foaming part J1 and the second foaming part J2 with an adhesive.

As mentioned above, although embodiment of the present invention and its modification were explained in detail, the resin panel and foam of the present invention are not limited to the above-mentioned embodiment and its modification, and in the range which does not deviate from the main point of the present invention, Of course, various improvements and changes may be made.
For example, in the above-described embodiment and its modification, the interior material as a foam is formed by connecting two foamed portions, but this is not a limitation. You may make it form the foaming area | region of a different foaming ratio simultaneously in one foam molding process.

  Hereinafter, the present invention will be further described by examples. However, this invention is not limited to the aspect shown in the Example.

(1) Production of Resin Panels According to Examples and Comparative Examples FIG. 19 shows the shape (substantially rectangular parallelepiped) and the configuration of the interior material provided in the resin panel according to the example.
As shown in FIG. 19, the foamed parts J1 to J3 were separately foam-molded and then connected to produce an interior material according to the example. The foaming part J2 has a hinge as shown in FIG. U-shaped grooves and U-shaped protrusions were set in the connecting portions of the foamed portions J1 and J2 and the connected portions of the foamed portions J2 and J3.
FIG. 20 shows the shape and configuration of the interior material provided in the resin panel according to the comparative example.
As shown in FIG. 20, the overall shape and size of the interior material of the comparative example are the same as those of the interior material of the example, but the point that the interior material of the comparative example was molded from a single foam material is different from the example.

As the interior material according to the examples and comparative examples, polystyrene (PS) and polyethylene (PE) foamed and molded (Piocelan (registered trademark) of Sekisui Plastics Co., Ltd.) were used.
In the interior material according to the example, the foaming ratio of the foamed portions J1 and J3 was 15 times, and the foaming ratio of the foamed portion J2 was 30 times.
In the interior material of Comparative Example 1, the expansion ratio was 30 times.
In the interior material of Comparative Example 2, the expansion ratio was 20 times.
In the interior material of Comparative Example 3, the expansion ratio was 15 times.
In the interior material of Comparative Example 4, the expansion ratio was 30 times.
The plate | board thickness of the interior material of the Example and Comparative Examples 1-4 was all 19 mm.

In the interior material of Comparative Example 4, aluminum cross-section I-type reinforcement (secondary moment of cross section: 3400 mm ⁴ ) was fitted to the foam material at four positions indicated by broken lines in FIG.

Next, as described with reference to FIG. 4 and FIG. 5, the interior material produced by forming a pair of molten resin sheets to be a skin material sheet between a pair of split molds and molding along a molding surface. Was welded to the molten resin sheet. Then, the split mold was clamped to form parting lines on the periphery of the pair of molten resin sheets. Further, the pair of split molds were moved to the open position, separated from the forming surface of the molded resin panel split mold, and the burrs were removed with a cutter to produce a resin panel.
Here, the molten resin used as the skin sheet was made of kneaded polypropylene (PP) and linear polyethylene (LLDPE), and the sheet thickness was 1.0 mm.
The thicknesses of the resin panels according to the examples and comparative examples were both 21 mm.

(2) Evaluation of samples according to Examples and Comparative Examples The rigidity of the resin panels according to Examples and Comparative Examples 1 to 4 was evaluated.
Specifically, first, as shown in FIG. 19 and FIG. 20, the pair of long side end portions of the substantially rectangular resin panel 1 is used as a base for the resin panels according to the examples and comparative examples. It was placed. Here, the span L between the tables was set to 500 mm or 600 mm.
Next, 20 kg, 40 kg, 60 kg, and 80 kg of load were applied to a 60 mm diameter range centering on points A and B in FIGS. 19 and 20, and the displacement was measured. In addition, A point is a center position of the area | region of the right side rather than a hinge in FIG.19 and FIG.20. In FIG. 19 and FIG. 20, the point B is the center of a pair of opposing long side ends and is 40 mm to the left from the right short side end.
Table 1 shows the results of measurement with the span L between the tables set to 500 mm, and Table 2 shows the results of measurement with the span L set to 600 mm. When the span L was 600 mm, the resin panel could be damaged, so the load was limited to 40 kg.

As shown in Table 1, when the span L between the tables is 500 mm, the displacement at the center A of the resin panel of the example is close to that of Comparative Example 1 (foaming ratio: 30 times), and the end It can be seen that the displacement of point B near the portion is close to that of Comparative Example 2 (foaming ratio: 20 times). Here, as shown in FIGS. 19 and 20, when the resin panel is placed on the table, the vicinity of the end portion on the short side of the resin panel (that is, the region including the point B) has the most rigid structure. Since it is a region that tends to be low, in the resin panel of the example, the overall expansion ratio was 20 times while the weight was lower than the expansion rate of 20 times overall, and the region with the lowest rigidity was overall 20 times. It was possible to be equivalent to the thing.
Moreover, when the displacement difference of A point and B point is compared, in the resin panel of an Example, since a displacement difference is entirely smaller than the comparative examples 1-3 except the comparative example 4 containing a reinforcement, end It can be seen that the part can be selectively reinforced.

  As shown in Table 2, the same result was obtained when the span L between the tables was 600 mm. That is, the displacement of the point A in the center of the resin panel of the example is close to that of the comparative example 4 (foaming ratio: 30 times), and the displacement of the point B near the end is that of the comparative example (foaming ratio: 20 times). You can see that they are close. Moreover, when the displacement difference of A point and B point is compared, in the resin panel of an Example, it turns out that a displacement difference is entirely smaller than the comparative examples 1-3 except the comparative example 4 containing a reinforcing material.

DESCRIPTION OF SYMBOLS 1 ... Resin panel S ... Skin material sheet 1a ... Front surface 1b ... Back surface 1c ... Long side wall surface 1d ... Short side wall surface 2, 2A, 2B, 2C, 2D, 2E ... Interior material (foam) Example)
2c: Long side wall surface 2d: Short side wall surface 21, 21A, 21B, 21C, 21D, 21E, 22, 22A, 22B, 22C, 22D, 22E, 23, 23A, 23D, 23E, 24E, 25E, 26E ... Foaming part 21Ch ... Handle 3 ... Reinforcing material 70 ... Clamping device 71A, 71B ... Split mold 72A, 72B ... Forming surface 74A, 74B ... Pinch-off part 75A, 75B ... Sliding part P ... Molten resin sheet ST ... Stand H ... Connection region J1 ... First foaming part J2 ... Second foaming part J1p, J2p ... Projection J1h, J2h ... Hole

Claims (6)

A plate-like foam,
A first foaming region composed of a first foaming ratio, and a second foaming region composed of a second foaming ratio lower than the first foaming ratio,
The second foam region is formed at least partially along the periphery of the foam, or is formed so as to cross from a part of the periphery of the foam to another part. And
Foam. The cross-sectional thickness of the second foam region is not uniform,
The foam according to claim 1. A hinge is formed on at least a part of the second foam region,
The foam according to claim 2. The first foam part having the first foam region and the second foam part having the second foam region are connected,
The foam as described in any one of Claims 1-3. In the connection region where the first foamed part and the second foamed part are connected, both the first foamed part and the second foamed part are between the front surface and the back surface of the foam. Characterized by having a portion penetrating
The foam according to claim 4.   The resin panel which covered the foam as described in any one of Claims 1-5 with the skin material sheet.

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