JP2001277275A - Mold and method for manufacturing multilayered molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a mold suitable for inexpensively manufacturing a multilayered molded artile having no problem in strength and the bonding strength of skin materials and generating no recessed part at the abutted edge parts of two kinds of the adjacent skin materials even if the skin materials each having a foam layer are used. SOLUTION: In the mold for manufacturing the multilayered molded article wherein two kinds of the skin materials are integrally bonded to the surface of a thermoplastic resin base material so as to be adjacent to each other, the recessed part corresponding to the abutted edge parts of two kinds of the skin materials is provided to the cavity surface of the mold on the skin material side among a pair of male and female molds at the place, where the adutted edge parts of the skin materials are positioned, of the cavity surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for producing a multilayer molded article in which two kinds of skin materials are bonded and integrated adjacent to the surface of a thermoplastic resin substrate, and to the production of a multilayer molded article using the same. About the method.

[0002]

2. Description of the Related Art Multilayer 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) because of their economical efficiency, light weight and good shapeability. ), Is widely used in interior and exterior parts of home appliances and other wide fields.

[0003] In such a multilayer molded product, in particular, a molded product in which two kinds of skin materials are bonded adjacent to each other on the surface of a thermoplastic resin substrate has conventionally been prepared by injection molding or compression molding. Substrate parts each having a surface material bonded to the surface were separately formed, and these were joined by heat fusion or the like in a later step.

[0004] In another method, a single surface material is bonded to the surface of a base material made of a thermoplastic resin by injection molding or compression molding, and another skin material is bonded using an adhesive or the like in a later step. I was aligned.

[0005] However, in the former case of such a multilayer molded product, the bonding between the two types of base materials is partial fusion, and the bonding strength may be insufficient. In the latter case, there is a problem such as peeling of the skin material.

[0006] To solve these problems, for example, two kinds of skin materials are overlapped in advance, the edges of which are sandwiched by a sandwiching body, and this is set in a groove provided in a mold to form a molten thermoplastic material. A method of supplying and molding a resin has been proposed (Japanese Patent Laid-Open No. 2-17 / 1990).
5111). According to this method, two types of adjacent skin materials can be simultaneously bonded and integrated, and a good multilayer molded product free from problems such as product strength and peeling of the skin material can be manufactured.

However, when a skin material having a foam layer is used as the skin material, the foam layer (FIG. 3) compressed in the mold at the time of molding recovers from compression when the pressure is released after molding. However, there is a problem that a groove-shaped concave portion is formed at the joint portion between the two kinds of skin materials (FIG. 4).

[0008]

SUMMARY OF THE INVENTION
The present inventors have found that even when a skin material having a foam layer is used, there is no problem in the product strength and the bonding strength of the skin material, and furthermore, there is no multilayer at the joint of two adjacent skin materials. As a result of studying a method and a mold for producing a molded product at low cost, the present invention has been achieved.

[0009]

The first aspect of the present invention is a mold for producing a multilayer molded product in which two kinds of skin materials are bonded and integrated adjacent to the surface of a thermoplastic resin base material. A multi-layer molded product having a concave portion corresponding to the mating portion at a position where the mating portion of the two types of skin materials on the mold cavity surface on the skin material side is located in the mold composed of a pair of male and female. It is intended to provide a manufacturing die.

[0010] The second aspect of the present invention is to provide a mold having a pair of male and female between molds.
Supplying two types of skin materials, supplying a molten thermoplastic resin between these skin materials and one mold, and bonding and integrating two types of skin materials adjacent to the surface of the thermoplastic resin base material. In the method for manufacturing a multilayer molded article, a concave portion corresponding to the mating portion is located at a position where the mating portion of the two types of skin materials on the mold cavity surface on the skin material side is located in the mold composed of a pair of male and female. It is intended to provide a method for producing a multilayer molded product using a mold having:

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 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.

FIG. 1 is a plan view showing an example of a multilayer molded product (1) manufactured by the method of the present invention as viewed from the skin material side. FIG. FIG. 2 shows a cross section when cut at A. FIG. In this multilayer molded product (1), a part of an edge of a first skin material (2) and a part of an edge of a second skin material (3) are adjacent to a surface of a thermoplastic resin base material (4) and bonded and integrated. The portions in contact with the edges overlap each other and are in a state of sunk into the molded article.

FIG. 5 is a schematic sectional view showing an example of a mold for manufacturing a multilayer molded product according to the present invention. In this example, the cavity surface of the female mold (6) is on the skin material side. Has become. This mold is composed of a pair of male and female members that slide on each other with the outer peripheral portion of the male die (5) and the inner peripheral portion of the female die (6) serving as sliding surfaces. At the position where the two types of skin materials meet on the mold cavity surface, an engagement groove (8) for engaging a holding body (7) for holding the two types of skin material ends together is provided. A molten resin supply port (10, 11) communicating with the molten resin supply device through a molten resin supply passage (9) is opened in 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 is preferably provided at a location corresponding to each of the two types of skin material bonding portions. The number and position may be appropriately determined according to the size and size.

[0015] On the cavity surface of the female mold (6), a groove-shaped concave portion (12) is provided at a position corresponding to a position where two kinds of skin materials meet. At the position where the two types of skin materials of the male mold (5) meet, the fitting groove (8) for fitting the holding body (7) holding the ends of the skin material as described above is provided. It can be said that the concave portion (12) is provided to face the fitting groove (8).

The shape of the concave portion (12) is not particularly limited. For example, the cross section may have any shape as shown in FIGS. 6 (a) to 6 (d), but the foam layer of the skin material is compressed at the time of mold clamping. It is necessary to make the shape such that a step from the surroundings does not occur when the vehicle recovers from the state of being left. The height (depth) of the concave portion (12) varies depending on the type and thickness of the skin material to be used. If it is too large, the edge of the foamed layer expands convexly due to the recovery of the foamed layer after molding, so its height (depth)
Is preferably equal to the recovery amount of the foam layer of the skin material used.

The width of the concave portion (12) also depends on the type and thickness of the skin material used, but if it is too small, the concave portion at the edge of the skin material is not eliminated due to the recovery of the foamed layer after molding, and it is too large. Because the foam layer recovers after molding, a convex portion is generated near the edge of the skin material, so the width should be about the thickness of the two types of skin material when compressed and the recovery amount of the foam layer added. However, it is also effective to make the width slightly larger and blur the shape. Such a concave portion (12) may be provided continuously at all positions corresponding to the joint portion of the two kinds of skin materials, or may be provided discontinuously only at a necessary portion. Further, the height and the width may be partially changed in the same shape, or the shape may be partially changed.

Next, a method of manufacturing 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 kinds of skin materials (2, 3) are overlapped and sandwiched by a sandwiching body (7).
The sandwiching of the skin materials (2, 3) only needs to be fixed so as not to cause a displacement during molding. In this example, the portion where the ends of the skin material are overlapped and the portion which is not sandwiched are defined. An alternate state is shown. That is, FIG.
7B, the ends of the skin material are firmly held by the holding body (7) as shown in FIG. 7B, but the portion of C--C in FIG. As shown in FIG. 7C, the ends of the skin material are not directly held by the holding body (7). Of course, it is optional how the end portions of the skin material are sandwiched by the sandwiching body, and the entire edge portion may be sandwiched as shown in FIG.
Usually, it is preferable to have a part where the ends of the skin material are firmly held by the holding body and a part which is not directly held, especially such parts are alternately arranged. Is preferred.

The holding body (7) illustrated in FIG.
As can be seen from FIG. 7 (a) and FIG. 7 (b), the structure is such that the left and right divided members are divided into two in the longitudinal direction, and when the left and right divided members are joined together, the skin is superimposed at the joint. It has a structure in which grooves of width and depth are provided such that the ends of the material can enter and be firmly sandwiched. In this example, by increasing the depth and width of the portion that firmly sandwiches the end portion of the skin material and the groove of the sandwiched portion, the end portions of the skin material are separated from the sandwiching body. A sandwiching portion is provided so that both portions are present alternately.

FIG. 8 shows a state in which a holding body (7) holding two kinds of skin materials (2, 3) is fitted into a fitting groove (8) provided in the cavity surface of the male mold (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.

The shapes of such a holding body and a fitting groove for fitting the holding body are not limited to these examples.
One described in Japanese Patent No. 175111 can also be employed.

FIG. 9 shows that a molten thermoplastic resin (13) is supplied from two molten resin supply ports (10) between the skin material (2, 3) set between the molds and the male mold (5). Shows where you are. 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 and the like. Further, when supplying the molten thermoplastic resin from each of the plurality of molten resin supply ports corresponding to the location where the two kinds of skin materials are bonded, the amount and timing of the resin supplied from each molten resin supply port Is appropriately determined according to the size and shape of the molded product.

After the molten thermoplastic resin is supplied, mold clamping is performed, or the mold clamping is started while supplying the molten thermoplastic resin, and the mold clamping is completed simultaneously with or after the completion of the supply. The cavity is filled with a fixed amount of the molten thermoplastic resin. FIG. 10 shows the state of the cavity after the completion of the mold clamping. FIG. 7A shows a portion where the skin material is sandwiched, and FIG. 10B shows a portion where the skin material is not sandwiched. , Respectively, shows a state where the mold is clamped.

As can be seen from this figure, in the portion shown in FIG. 7A, the thermoplastic resin serving as the base material is blocked by the two skin materials, but the two skin materials are misaligned. 7B, the thermoplastic resin serving as a base material wraps around and is integrated with the periphery of both ends of the skin material in the portion shown in FIG. 7B. . For this reason, if the skin material is sandwiched so that such portions are provided alternately, the base material portion to which the different skin materials are bonded is also integrated, and the end portion of the skin material may be displaced. Instead, both skin materials can be bonded to the base material adjacent to each other.

The timing of the mold clamping may be either during or after the supply of the molten thermoplastic resin, but when the mold is clamped after the completion of the supply of the molten thermoplastic resin, It is preferable to start mold clamping immediately after the supply of the molten thermoplastic resin is completed. Although the figure shows an example of the mold clamping of the male and female molds in the vertical direction, the mold clamping direction may be the vertical direction or the horizontal direction.

At the time of completion of the mold clamping, the skin material is in a state in which the foam layer is compressed in the sealed mold (FIG. 11), so that the joint portion between the two types of skin material is in the female cavity. Has a convex shape that follows the shape of the concave portion provided on the substrate. Thereafter, the molded product is taken out by cooling and solidifying and opening the male and female molds. The molded product taken out of the mold recovers the foam layer of the pasted skin material, and as shown in FIG. 12, it is possible to obtain a molded product having a preferable appearance without unevenness on the surface.

[0027] The skin material applied to the present invention may be any skin material having at least a foamed layer, and may be composed of only a foamed layer, or may be further laminated with a skin layer. It may be lined with a backing layer.

Examples of the foamed layer include foams of polyolefin such as polypropylene and polyethylene, foams of polyvinyl chloride, and soft or semi-rigid polyurethane foams.

Examples of the skin layer include fabrics and knits such as moquettes and tricots, non-woven fabrics such as needle punch carpets, and sheets or films of metal foils, thermoplastic resins and thermoplastic elastomers.

[0030] Examples of the backing layer include a nonwoven fabric, a synthetic resin sheet and a film. As the fibers constituting the nonwoven fabric, natural fibers such as cotton, wool, silk, hemp or synthetic fibers such as polyamide, polyester, nylon and the like 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, a spun lace type and the like can be mentioned. Examples of the synthetic resin sheet or film include a sheet or film made of a thermoplastic resin such as polypropylene or polyethylene or a polyolefin-based thermoplastic elastomer, and those having a fusibility with the thermoplastic resin used as the base resin are preferable. Used for

[0031] The thermoplastic resin applied to the present invention is a resin usually used in compression molding, injection molding, extrusion molding and the like, such as polypropylene, polyethylene, acrylonitrile styrene butadiene block copolymer,
Polyamide, polyamide such as nylon, polyvinyl chloride, polycarbonate, acrylic resin, general thermoplastic resin such as styrene-butadiene block copolymer, thermoplastic elastomer such as EPM or EPDM, a mixture thereof, or using these Polymer alloys and the like may be mentioned, and these may be non-foamable or foamable. In addition, these thermoplastic resins may contain fillers such as commonly used glass fibers and various inorganic or organic fillers, if necessary.Of course, various pigments and lubricants that are commonly used, Various additives such as an antistatic agent and a stabilizer may be blended.

[0032] Injection molding or compression molding is applied as a molding method for producing the multilayer molded article of the present invention. In the case of injection molding, the temperature and pressure of the molten resin are applied to the skin material during resin supply. Since compression is directly applied and damage to the skin material is likely to increase, compression molding that can reduce damage to the skin material by performing mold clamping as described above can be more preferably applied.

[0033]

According to the present invention, when a multilayer molded article is manufactured using the mold of the present invention, a thermoplastic resin substrate having a foamed layer on its surface can be used.
Even when two types of skin materials are bonded and integrated, there is no problem in product strength or the adhesion strength of the skin materials, and a multilayer molded product having no concave portion at the edge of the two types of skin materials is efficiently reduced. Can be manufactured at cost.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a multilayer molded product manufactured by using a mold of the present invention as viewed from a skin material side.

FIG. 2 is a cross-sectional view of the multilayer molded product shown in FIG. 1 along the line AA.

FIG. 3 is a cross-sectional view showing a state of a skin material adjacent portion in a mold when a multilayer molded product is manufactured using a conventional mold.

FIG. 4 is a cross-sectional view showing a state of a skin material adjacent portion when a 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 a shape of a concave portion provided in the mold of the present invention.

7A and 7B are schematic diagrams showing a holding body in which the ends of adjacent skin materials are held between each other, wherein FIG. 7A is a view of the holding body viewed from above, and FIG. 7B is a BB view of FIG. (C) shows a cross-sectional state at the time of cutting along C-C.

FIG. 8 is a schematic cross-sectional view of a mold in a state where a skin material is supplied in a manufacturing process of a multilayer molded product using the mold of the present invention.

FIG. 9 is a schematic cross-sectional view of a mold, illustrating a state in which a molten thermoplastic resin is supplied in a production process of a multilayer molded product using the mold of the present invention.

FIG. 10 is a schematic view of a cross section of a mold in a manufacturing process of a multilayer molded product using the mold of the present invention, after the mold is clamped, where (a) shows a portion where a skin material is sandwiched. To
(C) shows a portion where the skin material is not sandwiched.

FIG. 11 is a cross-sectional view showing a state of a skin material adjacent portion in a 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 the skin material adjacent portion when the mold is opened from the state shown in FIG. 11 and taken out as a product.

[Explanation of symbols]

 1: Multi-layer molded product 2, 3: Skin material 2 ', 3': Foam layer 4: Thermoplastic resin 5: Male type 6: Female type 7: Nipping body 8: Fitting groove 9: Molten resin supply passage 10: Molten resin Supply port 11: molten resin supply port 12: recess 13: molten thermoplastic resin

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F202 AD05 AD08 AD17 AD35 AG02 AG03 AG20 AG28 CA09 CB01 CB13 CB20 CB27 CK18 CK42 CL02 CQ03 CQ05 4F204 AD05 AD08 AD17 AD35 AG02 AG03 AG20 AG28 FA01 FB01 FB13 FB20 FB25 FF05 FF05 FF25 FG25 FN07 FQ01 FQ15

Claims (4)

[Claims] Claims: 1. A mold for producing a multilayer molded product in which two kinds of skin materials are bonded and integrated adjacent to the surface of a thermoplastic resin base material, wherein the skin is one of a pair of male and female molds. A mold for manufacturing a multilayer molded product, comprising a concave portion at a position corresponding to an edge of two kinds of skin materials on a mold cavity surface on a material side. 2. A method of supplying two kinds of skin materials between a pair of male and female molds and supplying a molten thermoplastic resin between the skin materials and one of the molds, thereby forming a surface of the thermoplastic resin base material. In a method of manufacturing a multilayer molded product in which two types of skin materials are bonded and integrated adjacently to each other, in a mold comprising a pair of male and female, a joining edge of two types of skin materials on a mold cavity surface on the skin material side A method for producing a multilayer molded product, comprising using a mold having a concave portion at a position corresponding to a part. [3] supplying two kinds of skin materials between unclosed molds,
A molten thermoplastic resin is supplied between the skin material and one of the mold surfaces, the mold is clamped, and the surface of the thermoplastic resin
The method for producing a multilayer molded product according to claim 2, wherein the kinds of skin materials are bonded and integrated. 4. The method for producing a multilayer molded product according to claim 2, wherein the skin material is a skin material having a foamed layer.