JPH0369287B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a foam molded product having a different skin part on a part of the product surface, more specifically, a foam molded product having a part of the skin of a synthetic resin sheet having a fabric skin part. The present invention relates to a method for manufacturing foam molded products such as foam molded products that have different color parts in some parts, and specific products that have the above-mentioned characteristics such as automobile interior parts such as automobile door trims, furniture, and building materials. . (Prior art) In recent years, foam molded products such as automobile interior parts, furniture, building materials, etc., as mentioned above, have been treated with fabric or different colored synthetic resins on a part of their surface due to consumer-oriented diversification and luxury. High demand. As shown in FIG. 4, the conventional structure and molding method of such a foamed molded product includes a base foamed body 23 formed by integrally laminating a foamed layer 21 and a shape-retaining layer 22 on the back surface of a skin 20. A different skin foam 27 is formed by integrally laminating a foam layer 25 and a shape-retaining layer 26 on the back side of a skin 24 of a different color and material from the previous skin 20.
A structure has been proposed in which a locking metal fitting 28 protrudes from a shape-retaining layer 26 of a different skin foam 27 and is fixed therein. The manufacturing method is to mold the base foam 23 and the different skin foam 27 separately, and then fix the different skin foam 27 at a predetermined position on the base foam 23. (Problems to be Solved by the Invention) As mentioned above, the foam molded product produced by the structure and manufacturing method of the prior art is a combination of separately molded foam molded products, and the foamed parts with dissimilar skins inevitably bulge. The shape is raised, and there is a difference in level between the surface of the base foam and the surface of the different skin foam, which creates an unnatural feeling.It also affects the work when attaching the different skin foam parts, and the molding accuracy of each foam. Up,
There was a drawback that a gap inevitably formed between the mating surfaces of both foams, and the parting line between the different types of skin became unclear. These drawbacks are truly serious problems for foamed molded products, for which good appearance is an important factor in determining commercial value, and an immediate solution has been desired. In addition, the conventional manufacturing method requires three main steps: molding the base foam, molding the different skin foam, and bonding both foams together, and the conventional foam molded product This method required significantly more man-hours than conventional molding, and the work efficiency was poor. The present invention has focused on these drawbacks of the prior art, and has developed a foaming method that eliminates unnatural bulges in dissimilar skin areas and gaps between mating surfaces, and reduces the number of man-hours required for production compared to conventional methods. The purpose is to provide a method for manufacturing molded products. (Means for Solving the Problem) Therefore, the feature of the present invention for achieving the above-mentioned object is to apply a different type of skin to at least one section of a mold having a projecting wall that partitions a molding surface into a plurality of sections. Further, a foam sheet is provided on the back surface of the different type of skin, and a core material is provided in a compressed state of the foam sheet on the back surface of the foam sheet, and a preformed base skin is provided on the molding surface of the other section. , a method for producing a foamed molded article, which involves injecting a hard urethane foam raw material into a mold, and removing the mold after the raw material has hardened. (Function) By producing a foam molded product using the above method, the base skin and the different skin are fixed together with the hard urethane foam, and the compressed foam sheet attached to the back of the different skin expands when the mold is removed. The core material installed on the back side of the foam sheet acts to fill the gap between the base skin of the protruding wall part of the lower mold and the different skin, and the core material that is installed on the back of the foam sheet not only works to adjust the appearance shape of the different skin, but also fills the gap between the base skin and the different skin of the protruding wall of the lower mold. It has the effect of preventing a large amount of foam from entering and impregnating the foam sheet, and prevents the foam sheet from losing its elasticity. (Example) Specific examples of the present invention will be further described below. 1 and 2 are cross-sectional views of a mold showing each step of an embodiment of the method for manufacturing a foam molded product of the present invention, and FIG. 3 is a cross-sectional view of a mold manufactured by the method for manufacturing a foam molded product of the present invention. FIG. Reference numeral 1 in FIG. 1 denotes a mold used in the method for producing a foamed molded product of the present invention, which is comprised of a pair of upper mold 2 and lower mold 3. The lower mold 3 has a molding surface for molding the surface shape of the molded object, and the molding surface is partitioned into two molding surfaces by a protruding wall 4 provided annularly in the center of the molding surface, i.e. It is partitioned into a different skin molding surface 5 and a different skin molding surface 6. Different skin molding surface 5 of the lower mold 3 of the mold 1 described above
A preformed heterogeneous skin 7 is provided in advance.
The base skin 7 is preformed using PVC resin, ABS resin, or other synthetic resin raw material as the main raw material, using slush molding, vacuum forming, or other known molding methods.
It is preferable to use a resin layer laminated with a foam layer such as foamed PVC or foamed PE, since the surface will be soft. Further, on the dissimilar epidermis molding surface 6 of the lower mold 3, a dissimilar epidermis 8 having different properties from the previous base epidermis is provided. As the different epidermis, synthetic resin or cloth, etc., which is generally different in color from the previous basal epidermis, is used.
When using cloth as the foreign skin, it is preferable to use stretchable cloth such as tricot jersey. Next, a compressed foam sheet 9 is placed on the back surface of the dissimilar skin 8, and a synthetic resin, steel, etc. is applied to the back surface of the foam sheet 9 to determine the appearance shape and lower mold of the dissimilar skin portion of the foam molded product, which is generally the final product. A core material 10 formed into a plate shape is equipped with a border at the end of the entire assembly so as to roughly match the projecting wall 4 of No. 3, and the back surface of the core material 10 is approximately
It is pressed by the positioning pin 11 protruding from the upper die 2, and is prevented from moving from the ruler position by the compressive restoring force of the foam sheet 9 or by vibrations during raw material casting. There is. The foam sheet used here needs to be easily compressible and have good recovery properties, but there are no particular limitations on the material etc.
For example, a foamed sheet of polyethylene, polypropylene, urethane, etc. with a foaming ratio of 25 to 100 times can be used. The foaming state can be either independent or continuous, but when closed cells are used, impregnation of the hard urethane foam can be prevented, and surface hardening can be prevented. In addition, the mold 1 for the foam sheet 9 and the core material 10 is
The setting procedure is not particularly limited, but the foam sheet 10 is provided on the back surface of the dissimilar skin 6, and the core body 10 is attached to the positioning pins 1 of the upper mold 2 in advance.
1, and when the upper mold 1 and lower mold 2 are combined together, the foam sheet 6 is compressed by the core 10. This method has good working efficiency. Next, as described above, the reference epidermis 7, the foreign epidermis 6,
A hard urethane foam 12 whose composition is shown in Table 1 is injected into the cavity of the mold 1 in which the foamed sheet 9 is set. (See Figure 2).

[Table] After the hard urethane foam 12 is cured, the upper mold 2 and lower mold 3 of the mold 1 are opened, and the foamed molded product is demolded. By doing so, the foam sheet 9 compressed and inserted into the mold 1 is released, the foreign skin 6 is expanded outward, and the projecting wall of the lower mold 3 that existed before being removed from the mold 1 is released. 4, the gap between the base skin 7 and the different skin 6 is eliminated, and a foamed molded product with a good external shape can be obtained. Although the above-mentioned embodiment discloses an embodiment using so-called closed molding in which the hard urethane foam is injected with the mold closed, the essence of the present invention is not limited to this in any way.
So-called open molding may be employed in which the upper and lower molds are sealed after the raw materials are injected with the upper and lower molds open. In addition, this example describes a case where the external shape of the foamed molded product is simple, but if the external shape of the foamed molded product is complex, for example, if the dissimilar skin part is not flat but has a curved surface or uneven surface, it may be necessary to , the foreign epidermis may lose its shape. If there is such a risk, deformation of the foam molded product can be prevented by applying an adhesive between the dissimilar skin and the foam layer, between the core material and the foam layer, or both. The heterogeneous skin can usually be sufficiently molded using unformed sheet-like cloth or synthetic resin, but depending on the external shape of the foam molded product, it may be partially preformed. Similarly, foamed sheets can usually be sufficiently molded using flat sheets, but depending on the external shape of the foamed molded product, parts may be preformed. (Effects) The method for manufacturing a foam molded product of the present invention uses a mold whose molding surface is divided into a plurality of parts by projecting walls, and a foam sheet is placed on the back side of a different skin, and a core material is placed on the back side of the foam sheet. In this state, the hard urethane foam raw material is injected into the mold, and after curing, the hard urethane foam material is removed from the mold.The hard urethane foam forms a bond between the base skin and the different skin, so the different skin is formed. It is possible to produce foam molded products that do not have unnaturally raised shapes or step differences, and the gap between the dissimilar epidermis and the base epidermis that exists during molding in the mold is eliminated. When the foam molded product is demolded, the foam sheet expands, resulting in the production of a foam molded product with no gap between the two and a clear separation between the base skin and the different skin. . In addition, the core material installed on the back side of the foam sheet prevents the hard urethane foam from penetrating the foam sheet, and has the effect of maintaining the soft feel of the surface. In addition, as mentioned above, the conventional manufacturing method requires three main steps: molding the base foam, molding the different skin foam, and bonding both foam molded products together. Compared to conventional methods, molding is completed in just one step, which has the effect of greatly improving work efficiency.

[Brief explanation of drawings]

1 and 2 are cross-sectional views of a mold showing each step of an embodiment of the method for manufacturing a foam molded product of the present invention, and FIG. 3 is a cross-sectional view of a mold manufactured by the method for manufacturing a foam molded product of the present invention. FIG. 4 is a sectional view of a conventional foam molded product. 2... Upper mold, 3... Lower mold, 4... Projection wall, 7... Base skin, 8... Different kind of skin, 9... Foam sheet, 10... Core material, 12... Hard urethane foam.

Claims (1)

[Claims] 1. A mold having a protruding wall that partitions the molding surface into a plurality of compartments is provided with a different type of skin in at least one section, a foam sheet is placed on the back side of the different type of skin, and a core material is placed on the back side of the foam sheet. The device is equipped in a compressed state, a pre-formed base skin is provided on the molding surface of the other section, a hard urethane foam raw material is injected into the mold, and the mold is removed after the raw material has hardened. A method for manufacturing foam molded products.