JP2010110942A - Void correction method of foamed molded article and foamed molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a void correction method of a foamed molded article capable of eliminating a hardening time until a void correcting chemical is hardened. <P>SOLUTION: In the void correction method of the foamed molded article constituted by integrally forming a front skin 3 in one face 2a and a core material 4 in the other face 2b sandwiching a urethane foamed body 2, a hole 6 is formed in the core material 4 so as to reach to a void 5 generated inside of the urethane foamed body 2, thereafter a foamed body particle 8 foamed and hardened in advance is injected into the void 5 from the hole 6, and the void 5 is filled with the injected foamed body particle 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

   The present invention relates to a method for correcting a void in a foam molded article and a foam molded article, and more particularly to a technique for correcting a void (air pocket) that may occur in a urethane foam part.

  For example, an instrument panel for an automobile generally has a skin formed on the surface of a urethane foam and a core material formed on the back. Urethane foams sometimes have voids that form air and accumulate in the interior during molding. Since the site where the void is formed is a cavity, the touch when touching the epidermis feels a dent compared to other sites.

For this reason, a void correction method has been proposed in which a urethane raw material containing a plasticizer is injected into a void so that the difference in feel from other parts is the same (for example, see Patent Document 1).
Japanese Utility Model Publication No. 6-98702

  However, in the method described in Patent Document 1, since the correction agent filled in the void correction portion is a raw material that stirs and cures the A liquid and the B liquid, it is in a fluid liquid state until it is cured. For this reason, this method requires a reaction curing time until the void correction agent is hardened, and the cycle time until the correction is completed becomes longer.

  Accordingly, an object of the present invention is to provide a method for correcting a void in a foam molded product and a foam molded product that can eliminate the curing time until the void correcting agent is hardened and can be used as a product immediately after the void correction.

  According to the first aspect of the present invention, in the void correction method for a foam molded product formed by integrally molding a skin on one surface and a core material on the other surface with a urethane foam sandwiched, voids generated inside the urethane foam After the hole is made in the core material so as to reach, foam particles that have been foam-cured in advance are injected into the void from the hole, and the void is filled with the injected foam particles.

  Invention of Claim 2 is the void correction method of the foaming molded article of Claim 1, Comprising: Shore A hardness of the said foam particle was 20-50, It is characterized by the above-mentioned.

  Invention of Claim 3 is the void correction method of the foaming molded article of Claim 1 or Claim 2, Comprising: The density of the said foam particle was 90-600 Kg / m <3>, It is characterized by the above-mentioned.

  Invention of Claim 4 is the void correction method of the foaming molded article of any one of Claims 1-3, Comprising: The said foam particle is spherical, ellipse, or those shapes. A plurality of protrusions are provided on the surface.

  Invention of Claim 5 is the void correction method of the foaming molded article of Claim 4, Comprising: One of the said foam particles is filled into a void, or several of the said foam particles are carried out. The void is filled.

  Invention of Claim 6 is the void correction method of the foaming molded article of any one of Claims 1-5, Comprising: The said foam particle is compressed and it fills and injects into a void. Features.

  The invention according to claim 7 is the void correction method for the foam molded article according to any one of claims 1 to 6, wherein the hole formed in the core material after the foam particles are injected. It is characterized by closing.

  The invention according to claim 8 is a foam molded product formed by integrally molding a skin on one surface and a core material on the other surface with a urethane foam sandwiched, and a foam generated inside the urethane foam is foam-cured in advance. The voids are filled by injecting the foam particles.

  According to the method of the present invention described in claim 1, since the foam particles that have been foam-cured and cured in advance are injected into the void, time for curing the injected foam particles is unnecessary, and the product is used as a product immediately after the injection. be able to. Therefore, according to the method of the present invention, the cycle time until the void correction is completed can be greatly shortened.

  According to the method of the present invention as set forth in claim 2, since the Shore A hardness of the foam particles is set to 20 to 50, the difference in hardness between the void portion and the other portion is alleviated, and the touch when touching the epidermis is substantially reduced. Be the same.

  According to the method of the present invention described in claim 3, since the density of the foam particles is set to 90 to 600 kg / m3, the difference in hardness between the void portion and the other portion is alleviated, and the touch when touching the epidermis is substantially reduced. Be the same.

  According to the method of the present invention as set forth in claim 4, by using a foam particle having a spherical shape, an elliptic shape, or a shape having a plurality of protrusions on the surface thereof, the void shape is easily formed as a spherical shape or an elliptic shape. By injecting a near void modifier, the void space can be filled almost without gaps.

  According to the method of the present invention described in claim 5, by filling one or more of the foam particles into the void, the space can be filled with the foam particles without any gaps depending on the shape of the void. In the case of a simple shape, a plurality of foam particles enter a fine shape portion to fill the space.

  According to the method of the present invention described in claim 6, since the foam particles are compressed and injected and filled into the voids, the low-density foam void modifier can be easily injected and filled into the voids.

  According to the method of the present invention as set forth in claim 7, since the hole formed in the core material after the foam particles are injected is closed with a breathable member, the void correction portion expands and contracts due to a temperature change or the like, thereby relaxing the unevenness. It is possible to prevent the appearance of the skin side from being damaged. As a result, it is possible to prevent occurrence of a weather-resistant appearance defect with respect to a change with time.

  According to the foam-molded article of the present invention according to claim 8, since the voids are filled by injecting foam particles that have been foam-cured in advance into the void, the void-corrected portion and the other portions are in a state immediately after injection. Altitude difference can be made substantially the same, and the touch feeling is the same in all parts.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  For example, as shown in FIG. 1, a foam molded product 1 used for an instrument panel such as an automobile includes a urethane foam 2, a skin 3 formed on one surface 2 a of the urethane foam 2, and another surface 2 b. The core material 4 is formed.

  The skin 3 is formed by, for example, powder flash molding or vacuum molding. As a material constituting the skin 3, for example, urethane, PVC (polyvinyl chloride), PVC / ABS (polyvinyl chloride / acrylonitrile butadiene styrene), or the like is used.

  Although it does not specifically limit for the urethane foam 2, The polyurethane foam, a polyethylene foam, a polypropylene foam, etc. which are normally used in this kind of field | area can be used.

  For the core material 4, PP (polypropylene) added with talc, or PPE (polyphenylin ether) with a glass fiber mixed therein is used.

  In addition, the material which comprises the above-mentioned outer skin 3, the urethane foam 2, and the core material 4 is an example, and is not limited to an above-described various material.

  The foamed molded article 1 is formed by integrally forming a skin 3 on one surface 2a of a urethane foam 2 and a core material 4 on the other surface 2b, but air enters the inside of the urethane foam 2 at the time of molding and becomes a cavity. A void 5 may be formed. Since the part where the void 5 occurs is recessed compared to the part where the void 5 does not exist, the feeling of the depression is poor when the skin 3 is touched. Therefore, in the present embodiment, foam particles previously foam-cured in the void 5 are injected as a void modifier, and the void 5 is filled with the injected foam particles. A specific void correction method will be described below.

  First, as shown in FIG. 1, a hole 6 is made in the core material 4 with a drill, a laser, or the like so as to reach the void 5 generated inside the urethane foam 2. The hole 6 formed in the core material 4 is set to φ2 mm to φ30 mm (preferably about φ5 mm to φ8 mm) in consideration of the size of the void 2 that is usually generated in the urethane foam. In the present embodiment, it is assumed that the shape of the void 5 is spherical.

  Next, as shown in FIG. 2 (A), the void correcting agent is put into the cylinder portion (cylinder) 7A of the void correcting agent filling device 7 composed of a syringe or the like. The inner diameter of the tip of the void modifier filling device 7 is desirably about φ3 mm to φ5 mm, which is a slightly smaller diameter than the hole 6 formed in the core material 4.

  As the void correcting agent, foam particles 8 that have been foam-cured in advance are used. As the foam particles 8, the same material as that of the urethane foam 2 is used. For example, a polyurethane foam, a polyethylene foam, a polypropylene foam, etc. are mentioned.

  Depending on the shape of the void 5, the foam particles 8 may be spherical as shown in FIG. 3A, elliptical as shown in FIG. 3B, or those as shown in FIGS. A plurality of protrusions 8a are provided on the surface of the shape. If the shape of the void 5 is spherical, spherical foam particles 8 corresponding to the shape are used, and if the shape of the void 5 is elliptical, elliptical foam particles 8 corresponding to the shape are used. In this embodiment, since the shape of the void 5 is an ellipse, the foam particles 8 filled in the void 5 are also elliptical. With respect to the size of the foam particles 8, those having a volume expansion after injection and having a size approximately the same as the volume of the void 5 are used.

  Further, the hardness of the foam particles 8 is preferably set to such a degree that the touch when touching the epidermis 3 is almost the same at the site where the void 5 is generated and the other site. For example, it is desirable that the hardness of the foam particles 8 is 20-50 in JIS standard Shore A hardness.

  Further, the density of the foam particles 8 is set to such a density that the touch is almost the same at the site where the void 5 is generated when the skin 3 is touched and at the other site. For example, the density of the foam particles 8 is preferably 90 to 600 kg / m 3.

  Next, as shown in FIG. 2 (B), the void correcting agent (foam particles 8) put in the cylindrical portion (cylinder) 7A of the void correcting agent filling device 7 is compressed by a presser (piston) 7B.

  Next, as shown in FIG. 4, the tip of the void modifier filling device 7 is inserted into the void 5 from the hole 6 formed in the core material 4. Then, the presser 7B is pushed in and the foam particles 8 are injected into the void 5 and filled. When the foam particles 8 are extruded into the void 5 from the compressed state, the volume is increased by returning to the original volume by the restoring function of urethane. As a result, the void 5 is completely filled with the injected foam particles 8 by the foam particles 8 whose volume has been increased. FIG. 4 shows an injection process of the foam particles 8 and shows a state before the foam particles 8 are completely increased in volume.

  After injecting the foam particles 8, the void modifier filling device 7 is pulled out from the void 5. Next, as shown in FIG. 5, the hole 6 opened in the core member 4 is closed with a sealing member 9 which is a breathable member. In this embodiment, the hole 6 is closed by sticking a tape having air permeability to the core material 4. In addition, as shown in FIG. 6, after the hole 6 is filled with a sealing material 9 made of a silicon-based adhesive or a urethane-based filler and cured, the small vent hole 10 is formed in the void 5 with a needle or a drill. Open to reach.

  By passing through the above process, the void 5 can be filled up with the void modifier without a gap. In the embodiment described above, one foam particle 8 is injected and filled in one void 5, but a plurality of foam particles 8 are injected and filled in one void 5 as shown in FIG. May be.

  In FIG. 7A, large and small foam particles 8 having a spherical shape with respect to the spherical void 5 are inserted into the void modifier filling device 7 and compressed, and then inserted through the holes 6 formed in the core material 4. Inject into 5 and fill. The small foam particles easily enter the gaps between the large foam particles and the voids 5 and fill up the internal space of the voids 5 without any gaps. FIG. 7B shows an example in which spherical foam particles 8 having a plurality of protrusions 8 a are injected and filled on the surface that is larger or smaller than the elliptical void 5. Not limited to these examples, spherical or elliptical foam particles 8 may be combined, or a combination of those large and small foam particles 8 may be used.

  According to the void correction method of the present invention, the foam particles 8 that have been foam-cured and cured in advance are injected into the void 5, so that no time is required to cure the injected foam particles 8 and the product is used as a product immediately after the injection. can do. When a liquid foam is used for the void correction agent, it takes several hours to cure. However, according to the method of the present invention, since the curing time is unnecessary, the cycle time until the void correction is completed is greatly shortened. be able to.

  Moreover, according to the void correction method of the present invention, since the Shore A hardness of the foam particles 8 is set to 20 to 50, the hardness difference between the void 5 portion and other portions is alleviated, and the skin 3 is touched. The feel is almost the same. When the hardness of the foam particles 8 is 20 to 50 in Shore A hardness, the hardness is almost the same as the hardness of the urethane foam 2 usually used in this type of instrument panel or the like. The feeling at that time is almost the same in the part where the void 5 is formed and the other part.

  Moreover, according to the void correction method of the present invention, since the density of the foam particles 8 is set to 90 to 600 kg / m 3, the hardness difference between the void 5 portion and other portions is alleviated, and the skin 3 is touched. The feel is almost the same. When the density of the foam particles 8 is 90 to 600 Kg / m 3, the density is almost the same as the density of the urethane foam 2 that is usually used in this type of instrument panel or the like. The feel is almost the same at the site where the void 5 is formed and at other sites.

  Further, according to the void correcting method of the present invention, the void 5 that is easily formed as a sphere or an ellipse by using the foam particles 8 as a sphere or an ellipse, or having a plurality of protrusions 8a on the surface of those shapes. By injecting the void correcting agent having a shape close to the above, the space of the void 5 can be filled almost without any gap.

  In addition, according to the void correcting method of the present invention, by filling one or more of the foam particles 8 into the void 5, the space is filled with the foam particles 8 without a gap according to the shape of the void 5. In the case of a complicated shape, the plurality of foam particles 8 enter a finely shaped portion and fill the space.

  Further, according to the void correcting method of the present invention, since the foam particles 8 are compressed and injected and filled into the void 5, the void correcting agent of low density foam can be easily injected and filled into the void 5. When the foam particles 8 are injected into the void 5 in a compressed state, the foam particles 8 fill the space of the void 5 without any gaps after the injection by the action of the foam particles 8 returning to the original volume in the void 5. I will do everything.

  Further, according to the void correction method of the present invention, since the hole 6 opened in the core material 4 after the foam particles 8 are injected is closed by the air-permeable sealing member 9, the void correction portion expands and contracts due to a temperature change or the like. Thus, the unevenness change can be alleviated, and the appearance on the skin side can be prevented from being damaged. As a result, it is possible to prevent occurrence of a weather-resistant appearance defect with respect to a change with time.

  According to the foamed molded product of the present invention, since the foam particles 8 previously foam-cured and hardened are injected into the void 5 and the void 5 is buried, the difference in height between the void-corrected portion and other portions is immediately after the injection. Can be made substantially the same, and the contact feeling is the same in all parts.

FIG. 1 is a cross-sectional view of a foam molded product in which voids are generated in a urethane foam. FIG. 2 is a view when foam particles precured in a void modifier filling device are put and compressed. FIG. 3 is a diagram showing an embodiment used as foam particles that are void correction agents. FIG. 4 is a cross-sectional view showing a state in which foam particles precured by a void modifier filling device are injected and filled into voids. FIG. 5 is a cross-sectional view showing a state in which a hole formed in the core member is closed with a tape having air permeability. FIG. 6 is a cross-sectional view showing an example in which air holes are formed after the holes formed in the core material are closed with an adhesive. FIG. 7 is a diagram showing an example in which large and small spherical foam particles are injected and filled into one void.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Foam molded article 2 ... Urethane foam 3 ... Skin 4 ... Core material 5 ... Void 6 ... Hole 7 ... Void correction agent filling device 8 ... Foam particle (void correction agent)
8a ... protrusion (protrusion formed on the surface of the foam particle)
9. Sealing material

Claims (8)

In the void correction method for a foam molded product formed by integrally molding the outer skin (3) on one surface (2a) and the core material on the other surface (2b) across the urethane foam (2),
After opening a hole (6) in the core material (4) so as to reach the void (5) generated in the urethane foam (2), the void (6) is passed through the hole (6) in advance. Injecting foam-cured foam particles (8) and filling the voids (5) with the injected foam particles (8). A void correction method for a foam molded article according to claim 1,
A method for correcting a void in a foam molded article, wherein the foam particle (8) has a Shore A hardness of 20 to 50. A void correction method for a foam-molded article according to claim 1 or 2,
A method for correcting a void in a foamed molded product, wherein the density of the foam particles (8) is 90 to 600 kg / m3. A void correction method for a foamed molded product according to any one of claims 1 to 3,
The foam particle (8) has a spherical shape, an ellipse shape, or a plurality of protrusions on the surface thereof. A void correction method for a foamed molded product according to claim 4,
One of the foam particles (8) is filled in the void (5), or a plurality of the foam particles (8) are filled in the void (5). How to fix. A void correction method for a foamed molded product according to any one of claims 1 to 5,
A method for correcting a void in a foamed molded article, wherein the foam particles (8) are compressed and injected into a void (5). A void correction method for a foamed molded article according to any one of claims 1 to 6,
A method for correcting a void in a foamed molded article, wherein after the foam particles (8) are injected, the hole (6) formed in the core material (4) is closed with a breathable member (9). In the foam molded product formed by integrally molding the outer skin (3) on one side (2a) and the core (4) on the other side (2b) across the urethane foam (2),
Foam molded product, wherein the void (5) is filled by injecting foam particles (8) previously foam-cured into the void (5) generated inside the urethane foam (2). .

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