JP4613388B2 - Mold for producing multilayer molded article and method for producing multilayer molded article - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mold for producing a multilayer molded article in which two types of skin materials are bonded and integrated on the surface of a thermoplastic resin substrate, and a method for producing a multilayer molded article using the same.
[0002]
[Prior art]
Multi-layer molded products in which a skin material is bonded to the surface of a base material made of a thermoplastic resin are used for automobile interior parts (for example, door trims and instrument panels) and home appliances because of their economy, light weight, and good formability. It is widely used in interior and exterior parts and other wide fields.
[0003]
In such a multilayer molded product, in particular, a molded product in which two types of skin materials are adjacently bonded to the surface of a thermoplastic resin base material has been conventionally applied to the surface of the thermoplastic resin base material by injection molding or compression molding. The base material parts to which the skin material was bonded were molded separately, and these were joined in the subsequent process by heat fusion or the like.
[0004]
In another method, a single surface material was bonded to the surface of a base material made of a thermoplastic resin by injection molding or compression molding, and another surface material was bonded using an adhesive or the like in a subsequent process. .
[0005]
However, in such a multilayer molded product, in the former case, the joining between the two types of base materials is a partial fusion, and the joining strength may be insufficient. In the latter case, there is a problem such as peeling of the skin material.
[0006]
For these problems, for example, two kinds of skin materials are stacked in advance, and the edges are sandwiched between sandwiched bodies, which are set in grooves provided in the mold and supplied with molten thermoplastic resin. Thus, a method for molding is proposed (JP-A-2-175111).
According to this method, two types of adjacent skin materials can be bonded and integrated at the same time, and a good multilayer molded product free from problems such as product strength and skin material peeling can be produced.
[0007]
However, when a skin material having a foam layer is used as the skin material, the foam layer (FIG. 3) compressed in the mold during molding recovers from compression when the pressure is released after molding. There is a problem that a groove-like recess is formed at the edge of the type of skin material (FIG. 4).
[0008]
[Problems to be solved by the invention]
For this reason, the present inventors have no problem in the product strength and the joining strength of the skin material even when the skin material having the foam layer is used, and the joint between the two adjacent skin materials. As a result of studying a method and a mold for producing a multilayer molded product having no concave portion at a low cost, the present invention has been achieved.
[0009]
[Means for Solving the Problems]
1st of this invention is a metal mold | die for manufacture of the multilayer molded product by which two types of skin materials adjoined and integrated on the surface of the thermoplastic resin base material, Comprising: A mold for manufacturing a multilayer molded product having a recess corresponding to the edge portion at a position where the edge portion of the two types of skin material is located on the surface of the mold cavity on the skin material side. is there.
[0010]
In the second aspect of the present invention, two types of skin materials are supplied between a pair of male and female molds, a molten thermoplastic resin is supplied between these skin materials and one mold, and a thermoplastic resin base material is provided. In the manufacturing method of a multilayer molded product in which two types of skin materials are bonded and integrated adjacent to each other on the surface of the mold, two types of skin materials on the surface of the mold cavity on the skin material side of the mold made of a male and female pair The present invention provides a method for producing a multilayer molded article using a mold having a recess corresponding to the edge portion at a position where the edge portion is located.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
This description is an example of the present invention, and the present invention is not limited to this.
[0012]
FIG. 1 shows an example of a multilayer molded article (1) produced by the method of the present invention in a plan view seen from the skin material side, and FIG. 2 shows the multilayer molded article in Table 1 cut along AA. The cross section when doing is shown. In this multilayer molded article (1), a part of the edges of the first skin material (2) and the second skin material (3) is adjacent to and integrated with the surface of the thermoplastic resin base material (4). The portions that are in contact with the end edges overlap with each other and are embedded in the molded product.
[0013]
FIG. 5 shows an example of a mold for producing a multilayer molded product according to the present invention in a schematic cross-sectional view. In this example, the cavity surface of the female mold (6) is on the skin material side. . This mold is composed of a male and female pair in which the outer peripheral part of the male mold (5) and the inner peripheral part of the female mold (6) are slid to each other. the position where the two types of surface material of the mold cavity surface is Goen, two clamping bodies for holding the skin material end portions (7) fitting groove for fitting (8) is provided In addition, molten resin supply ports (10, 11) communicating with the molten resin supply device through the molten resin supply passage (9) are opened on the mold cavity surface.
[0014]
The molten resin supply port may be provided at a location corresponding to at least one of the skin material bonding portions, but preferably provided at a location corresponding to each of the bonding portions of the two types of skin material, and the product shape and size. The number and position may be determined as appropriate according to the above.
[0015]
On the cavity surface of the female die (6), a groove-like recess (12) is provided at a location corresponding to a position where two kinds of skin materials are joined. Incidentally, the male (5) Two kinds of skin materials is Goen position of the fitting groove for fitting clamping body (7) for holding the skin material end portions as described above (8) is provided, the recess (12) is also said to be provided opposite to the fitting groove (8).
[0016]
There is no restriction | limiting in particular in the shape of a recessed part (12), For example, although the cross section should just be a shape as shown to Fig.6 (a)-(d), from the state by which the foam layer of the skin material was compressed at the time of mold clamping It is necessary to make a shape that does not cause a difference in level from the surroundings when recovered.
The height (depth) of the recess (12) varies depending on the type and thickness of the skin material to be used, but if it is too small, the recess at the skin material edge due to recovery of the foamed layer after molding is not eliminated and is large. If it is too high, the marginal portion will bulge out due to the recovery of the foamed layer after molding, and therefore the height (depth) is preferably equal to the recovery amount of the foamed layer of the skin material used.
[0017]
Further, the width of the concave portion (12) also varies depending on the type and thickness of the skin material to be used, but if it is too small, the concave portion of the skin material edge portion is not eliminated due to the recovery of the foam layer after molding, and if too large, after molding. As the foamed layer recovers, a convex portion is formed near the skin material edge, so the width needs to be the extent to which the foamed layer recovery amount is added to the thickness of the two skin materials when compressed. However, it is also effective to make the width slightly larger and blur the shape.
Such recesses (12) may be continuously provided at all positions corresponding to the edge portions of the two types of skin materials, but may be provided discontinuously only at necessary portions. Further, the height and width may be partially changed with the same shape, or the shape may be partially changed.
[0018]
Next, a method for producing a multilayer molded product using such a mold will be described.
FIG. 7A is a plan view schematically showing an example in which the edges of two types of skin materials (2, 3) are overlapped and sandwiched between the sandwiching bodies (7).
The skin material (2, 3) may be clamped as long as it does not cause misalignment at the time of molding. In this example, the portion of the skin material that is sandwiched between the overlapping portions and the portion that is not sandwiched are included. The alternate state is shown.
That is, as shown in FIG. 7 (b), the BB portion of FIG. 7 (a) is firmly held between the ends of the skin material by the holding body (7). As shown in FIG. 7 (c), the end portions of the skin material are not directly sandwiched between the sandwiching bodies (7).
Of course, it is arbitrary how the end portions of the skin material are sandwiched between the sandwiching bodies, and all of the edge portions may be sandwiched as shown in FIG. It is preferable to have a portion in which the portions are firmly clamped by the clamping body and a portion that is not directly clamped, and it is particularly preferable that such portions are alternated.
[0019]
The sandwiching body (7) illustrated in FIG. 7 has a structure that can be divided into left and right parts in the length direction as can be seen from FIGS. 7 (a) and 7 (b). When the members are combined, the end portions of the skin material overlapped at the joint portion enter, and a groove having a width and a depth that can be firmly sandwiched is provided. And in this example, the depth and width of the portion of the skin material firmly clamped and the groove of the clamping portion are increased so that the edges of the skin material are separated from the sandwiched body. A sandwiching portion is provided, and both portions are alternately present.
[0020]
Figure 8 shows the two states in which fitted into the fitting groove (8) provided in the cavity surface of the skin material (2, 3) and nipped clamping body (7) male (5).
At this time, a skin material clamp frame (not shown) may be provided on the outer periphery of the male mold (5) to fix the outer periphery of the skin material.
[0021]
Such a shape of the fitting groove holding member and fitting it is not limited to these examples, may be employed such as those described in JP-A-2-175111 mentioned above.
[0022]
In FIG. 9, molten thermoplastic resin (13) is supplied from two molten resin supply ports (10, 11) between the skin material (2, 3) set between the molds and the male mold (5). However, it shows.
The cavity clearance between the male and female molds when supplying the molten thermoplastic resin is appropriately determined depending on the type of skin material used. In addition, when supplying a molten thermoplastic resin from a plurality of molten resin supply ports corresponding to locations where two types of skin materials are bonded, the amount of resin supplied from each molten resin supply port and the supply timing Is appropriately determined according to the size and shape of the molded product.
[0023]
After the molten thermoplastic resin is supplied, the mold is clamped, or the mold is started while supplying the molten thermoplastic resin, and the mold clamping is completed simultaneously with the completion of the supply or after the supply is completed, and a predetermined amount of melting is performed. Fill the cavity with a thermoplastic resin.
FIG. 10 shows the state of the cavity after completion of mold clamping . FIG. 10 (a) is a part holding the skin material, and FIG. 10 (b) is a part not holding the skin material. The state where the mold is clamped is shown.
[0024]
As can be seen from this figure, in the portion shown in FIG. 10 (a), the thermoplastic resin as the base material is blocked by both skin materials, but both skin materials are displaced. It is firmly fixed at a predetermined position, and on the other hand, in the portion shown in FIG. 10 (b), the thermoplastic resin as the base material wraps around the end portions of both skin materials and is integrated.
For this reason, if the skin material is sandwiched so that such portions are alternately provided, the base material portion to which the different skin materials are bonded is also integrated, and the edge portion of the skin material may be displaced. In addition, both skin materials can be adjacently bonded to the base material.
[0025]
The timing of mold clamping may be either while supplying the molten thermoplastic resin or after completion of the supply, but when performing mold clamping after completing the supply of the molten thermoplastic resin, It is preferable to start clamping immediately after the completion of the supply of the thermoplastic resin.
Moreover, although the example of the mold clamping of the male-female mold is shown in the drawing in the vertical direction, the mold clamping direction may be the vertical direction or the horizontal direction.
[0026]
When the mold clamping is completed, the skin material is in a state where the foamed layer is compressed (FIG. 11) in the hermetically sealed mold, and therefore, the two edge portions of the skin material are provided in the female cavity. It becomes a convex shape along the shape of the concave portion.
Thereafter, the molded product is taken out by cooling and solidifying and opening both the male and female molds. The molded product taken out from the mold recovers the foamed layer of the laminated skin material, and as shown in FIG. 12, a molded product having a preferable appearance with no irregularities on the surface can be obtained.
[0027]
The skin material applied to the present invention may be a skin material having at least a foamed layer, may be composed of only a foamed layer, may be further laminated with a skin layer, and may also be a backing layer. May be lined with.
[0028]
Examples of the foamed layer include polyolefin foams such as polypropylene and polyethylene, polyvinyl chloride foams, soft or semi-rigid polyurethane foams, and the like.
[0029]
Examples of the skin layer include woven fabrics such as moquettes and tricots, knitted fabrics, nonwoven fabrics such as needle punch carpets, sheets or films of metal foil, thermoplastic resin, and thermoplastic elastomer.
[0030]
Moreover, as a backing layer, a nonwoven fabric, a synthetic resin sheet, a film, etc. are illustrated.
As the fibers constituting the nonwoven fabric, natural fibers such as cotton, wool, silk, hemp and the like, or synthetic fibers such as polyamide, polyester, nylon, etc. can be used. Used. For example, non-woven fabrics such as a needle punch type, a thermal bond type, a spun bond type, a melt blow type, and a spun lace type are listed.
Examples of synthetic resin sheets and films include sheets and films made of thermoplastic resins such as polypropylene and polyethylene, and polyolefin-based thermoplastic elastomers, and those that are fusible with the thermoplastic resin used as the base resin are suitable. Used for.
[0031]
The thermoplastic resin applied to the present invention is a resin usually used in compression molding, injection molding, extrusion molding, etc., for example, polypropylene, polyethylene, acrylonitrile-styrene-butadiene block copolymer, polyamide such as polystyrene, nylon, etc. General thermoplastic resins such as polyvinyl chloride, polycarbonate, acrylic resin, styrene-butadiene block copolymer, thermoplastic elastomers such as EPM and EPDM, mixtures thereof, polymer alloys using these, and the like These may be non-foaming or foaming.
In addition, these thermoplastic resins may contain fillers such as glass fibers, various inorganic or organic fillers that are usually used as necessary, and of course, various pigments, lubricants that are usually used, Various additives such as an antistatic agent and a stabilizer may be blended.
[0032]
As a molding method for producing the multilayer molded article of the present invention, injection molding or compression molding is applied, but in the case of injection molding, the temperature and pressure of the molten resin are directly applied to the skin material during resin supply, Since damage to the skin material is likely to increase, compression molding that can reduce damage to the skin material by performing mold clamping after supplying the molten resin as described above can be more preferably applied.
[0033]
【The invention's effect】
If a multilayer molded article is manufactured using the mold of the present invention, even if two types of skin materials having a foam layer are bonded and integrated on the surface of a thermoplastic resin substrate, the product strength and skin There is no problem in the adhesive strength of the material, and a multi-layer molded product having no recess at the edge of the two types of skin material can be produced efficiently and at low cost.
[Brief description of the drawings]
FIG. 1 is a plan view of an example of a multilayer molded product manufactured using a mold according to the present invention as viewed from the skin material side.
FIG. 2 is a cross-sectional view of the multilayer molded product shown in FIG. 1 taken along the line AA.
FIG. 3 is a cross-sectional view showing a state of an adjacent portion of a skin material in a mold when a multilayer molded product is manufactured using a conventional mold.
4 is a cross-sectional view showing a state of an adjacent portion of the skin material when the mold is opened from the state shown in FIG. 3 and taken out as a product.
FIG. 5 is a schematic sectional view of a mold according to the present invention.
FIG. 6 is a cross-sectional view showing an example of the shape of a recess provided in the mold of the present invention.
7A and 7B are schematic views showing a sandwiched body in which the ends of adjacent skin materials are sandwiched between each other, wherein FIG. 7A shows the state viewed from above, and FIG. 7B shows the state of BB in FIG. The cross-sectional state when cut is shown, and (c) shows the cross-sectional state when cut along CC.
FIG. 8 is a schematic view of a cross section of a mold, showing a state when a skin material is supplied in a manufacturing process of a multilayer molded article using the mold of the present invention.
FIG. 9 is a schematic view of a mold cross section showing a state at the time of supplying a molten thermoplastic resin in a manufacturing process of a multilayer molded article using the mold of the present invention.
FIG. 10 is a schematic view of a mold section in a manufacturing process of a multilayer molded product using the mold of the present invention, and (a) is a portion sandwiching a skin material (C) has shown the part which has not pinched the skin material.
FIG. 11 is a cross-sectional view showing the state of the adjacent portion of the skin material in the mold when a multilayer molded product is manufactured using the mold of the present invention.
12 is a cross-sectional view showing a state of an adjacent portion of the skin material when the mold is opened from the state shown in FIG. 11 and taken out as a product.
[Explanation of symbols]
1: Multilayer molded product 2, 3: Skin material 2 ′, 3 ′: Foam layer 4: Thermoplastic resin 5: Male mold 6: Female mold 7: Clamping body 8: Fitting groove 9: Molten resin supply passage 10: Molten resin Supply port 11: Molten resin supply port 12: Concave portion 13: Molten thermoplastic resin

Claims (3)

A mold for producing a multilayer molded article in which a skin material having two types of foam layers is adjacently bonded and integrated on the surface of a thermoplastic resin substrate,
Of the molds consisting of a pair of males and females, one mold has a recess at a position corresponding to the edge of the two types of skin material on the surface of the mold cavity on the skin material side,
Other mold, the multilayer molded article produced, characterized in that it comprises a holding member for holding the respective ends of the skin material at a position opposed to the concave portion, a fitting groove for fitting the holding member Mold. Two types of skin material are supplied between a pair of male and female molds, molten thermoplastic resin is supplied between these skin materials and one mold, and two types of skin material are provided on the surface of the thermoplastic resin substrate. In the method for producing a multilayer molded product in which materials are bonded and integrated adjacently,
Each of the skin materials is a skin material having a foam layer,
A method for producing a multilayer molded article, wherein the mold comprising a pair of males and females has a recess at a position corresponding to an edge part of two types of skin material on the surface of the mold cavity on the skin material side.   Two types of skin material are supplied between unclosed molds, molten thermoplastic resin is supplied between these skin materials and one mold surface, and the surface of the thermoplastic resin base material is clamped The method for producing a multilayer molded article according to claim 2, wherein two kinds of skin materials are bonded and integrated together.

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