JP2001277289A - Injection molding in-mold decorating method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding in-mold decorating method and apparatus capable of efficiently manufacturing a decorative laminated product having an undercut part without generating pattern extension, wrinkles, a rupture or the like. SOLUTION: The injection molding in-mold decorating apparatus has a clamp means 20 for pressing a pattern sheet S to the parting surface 14 of a female mold 12 provided with a slide core 12B for forming an undercut part to fix and hold the same, a sheet stretching means 15 for stretching the pattern sheet S along the cavity 13 of the female mold 12 and a resin injection means for injecting a resin in the molding cavity formed between the female mold 12 and a male mold in a flowable state to fill the cavity and is provided with a sheet preforming means 25 for preliminarily preforming the part Sa to be bonded and laminated of the pattern sheet S so as to protrude the same toward the cavity 13 of the female mold before stretching the pattern sheet S.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for obtaining a decorative laminated product by integrally bonding and laminating a painted sheet on which patterns and characters are applied in a mold simultaneously with injection molding on the surface of an injection resin molded article. And a method and apparatus for simultaneous painting by injection molding.

[0002]

2. Description of the Related Art Several methods have been proposed for simultaneous injection molding and painting methods in which a painting sheet is integrally adhered to the surface of an injection resin molded article simultaneously with injection molding.
Most of them are arranged so that all or some of the following steps (a) to (i) are performed in the stated order or permuted, and the steps are sequentially performed or a plurality of steps are simultaneously performed in parallel or in parallel. (Japanese Patent Publication No. 50-19132, Jitsuhei 3
-56344, JP-B-7-41637, etc.).

(A) A sheet supply step of supplying a picture sheet onto a female parting surface used for injection molding. (B) a clamping step of fixing and holding the painted sheet on the female parting surface; (C) A heating softening step of heating and softening the painted sheet with a hot platen or the like. (D) A sheet stretching step (preliminary molding step) of stretching the picture-sheet by vacuum suction and / or compressed air supply so as to follow the female cavity.

(E) A mold clamping step in which one of the female mold and the male mold (usually a female mold) is moved to the other (usually a male mold) to perform mold clamping. (F) An injection molding step of injecting and filling a resin (molten resin) in a flowing state from the male mold side into a molding cavity formed between the female mold and the male mold to perform injection molding. (G) A mold opening step of separating the female mold and the male mold. (H) A sheet trimming step of separating a portion of the painted sheet to be attached to the injection resin molded body from another portion (excess portion). (I) A take-out step of taking out the laminated product on which the painted sheet is adhesively laminated from both the male and female molds.

[0005] Simultaneously performing a plurality of steps simultaneously means that a plurality of steps are included in one step. For example, in the mold clamping step (e), the painted sheet is divided into a female type and a male type. If it is not fixed and held between them, the clamping step (b) is performed simultaneously with the mold clamping step, and the painted sheet is used in the injection molding step (f). If the stretching is performed by the heat and pressure of the injected molten resin, this means that the stretching step (d) is performed simultaneously with the injection molding step.

[0006] As the painting sheet, either a laminated sheet (laminated sheet) or a transfer sheet is used depending on the product type. In the case of a laminated sheet, painting is performed as it is by injection molding. That is, all the layers of the sheet are bonded and integrated with the surface of the injection resin molded body to form a decorative layer. On the other hand, when the painting sheet is a transfer sheet, the support sheet of the painting sheet integrated with the surface of the injection resin molded body is peeled off, and only the transfer layer such as the decoration layer remains on the injection resin molding body side. Then, the painting is completed by forming a decorative layer.

The decorative laminated product P to be obtained by the simultaneous injection molding and painting method as described above is shown in FIG.
As shown in (A) and (B), there are some which have undercut portions Pu and Pu which are caught by a normal female mold when taken out from the female mold cavity after the injection molding step.

In order to obtain a decorative laminated product P having such an undercut portion Pu, it is necessary to form a part of the female cavity up to the injection molding step and to retreat so as not to hinder the removal step. It is common to provide a slide core that can. Hereinafter, an example of a simultaneous injection molding painting apparatus and method for obtaining a decorative laminated product P having the undercut portion Pu using a female mold provided with the slide core will be described with reference to FIGS. 10 to 12. Will be explained.

The illustrated simultaneous injection molding painting apparatus 10 'is
The female mold 12 includes a female mold 12 and a male mold 30. The female mold 12 has a bottom portion (left end side in the figure) fixed to a movable plate (not shown), and is horizontally moved by a ram or the like of a fluid pressure cylinder. (X direction in the drawing), in other words, it moves forward and backward in a direction approaching and separating from the male mold 30.

The female die 12 has a main body 12A and a slide core 1 slidably disposed vertically above and below the right end (the male die 30 side) of the main body 12A (Z direction in the drawing).
2B and 12B, and a cavity 13 corresponding to the shape of the decorative laminated product P to be obtained is formed by the main body 12A and the slide cores 12B and 12B. Of the cavity 13, the slide core 12
The inclined surfaces (undercut end surfaces) 13u, 13u, which are inclined in the direction to narrow the opening of the cavity 13 on the right end side formed by B, 12B, form the undercut portions Pu, Pu of the decorative laminated product P. Part.

The cavity 13 is provided with a large number of vacuum suction holes 15, 15,... For vacuum suction in order to extend the painting sheet S along the cavity 13. , 15, ... are connected to a vacuum source (not shown) including an external vacuum pump and the like via a vacuum suction passage 18 and a conduit 19.

An end surface (right end surface) of the female die 12 on the male die 30 side including the slide cores 12B, 12B is formed by a parting surface 34 of the male die 30 and a clamper 20 'to be described later. It is a flat parting surface 14 that can be sandwiched and contacted.

On the other hand, although not shown, the male mold 30 is fixed to a fixed plate on which a nozzle of an injection molding machine is mounted, and the male mold 30 has a decorative laminated product P to be obtained.
And a runner 32 for injecting the molten resin and a gate 33 connected to the runner 32 are provided in the center of the inside.

The female mold 12 has a rectangular shape in plan view as viewed in the X direction in FIG. 1 so that the supplied one-shot sheet S for painting is pressed and held on the parting surface 14. A frame-shaped or double-girder-shaped clamper 20 'is provided. The clamper 20 'can move forward and backward in a direction perpendicular to the parting surface 14 (X direction in the figure) by driving means (not shown) through four sliding rods 24 connected to four corners thereof. It has become.

Further, in order to perform preforming, the hot platen 40 '
Is provided. The hot platen 40 'is held on one side of the female die 12 by a hot plate driving means (not shown) such as an air cylinder which is attached and held so as to move integrally therewith. From the position, the sheet is inserted between the dies and moved to a heated position of the painted sheet on the parting surface 14 of the female mold 12 (a position in contact with the clamper 20 as shown in FIG. 12), and the painted sheet S is moved. Is heated and softened. Here, the hot platen 40 'heats the sheet S with the non-contact heating method using infrared radiation.

On the other hand, above the female mold 12 (on the upstream side when viewed in the sheet supply direction), a roll for supplying a painting sheet (laminated sheet) S on the parting surface 14 of the female mold 12 is provided. Discharge machine 3, a pair of feed rollers (nip rollers) 4, guide rollers 5, a transport chuck 50 that can be opened and closed and held.
Are arranged. The transport chuck 50 is a leading end portion Se of the picture sheet S unwound from the unwinding machine 1 loaded with the long strip-shaped picture sheet (sheet roll).
The transfer chuck 50 grips the vicinity and conveys the parting surface 14 of the female mold 12 from the top to the bottom and near the lower end thereof.
The piston driving rod 52a is attached to the distal end of the piston rod 52a, and passes between the female parting surface 14 and the clamper 20 'from the standby position shown by the solid line in FIG. It is lowered straight (the imaginary line in FIG. 10) and raised along the Z direction = vertical direction.

The unwinding machine 3, the feed roller 4, the guide roller 5, and the chuck driving cylinder 52 are attached to the female mold 12 via supporting members (not shown), respectively. The male mold 30 can be moved toward and away from the male mold 30.

An opening / closing-type receiving / fixing chuck 60 is disposed below the male and female molds 12 and 30 (on the downstream side when viewed in the sheet feeding direction). The receiving and fixing chuck 60 is for receiving and temporarily holding and fixing the front end portion Se of the picture sheet S conveyed by the conveying chuck 50.
Are fixedly mounted on a support member (not shown) attached to the first member.

Further, after the clamping step, a sheet cutting means is provided so as to cut the pictorial sheet S supplied onto the female parting surface 14 into one-shot sheets at a position upstream of the clamper 20 '. Is provided as a cutter 55. The cutter 55 is fixed to a female mold, a hot platen, or the like by a support (not shown).

When performing simultaneous injection molding painting by the simultaneous injection molding painting apparatus 10 ′ having the above-described configuration, first, the painted sheet S is placed on the female parting surface 1.
In order to supply the sheet S on the picture sheet S, the vicinity of the front end Se of the painting sheet S unwound from the unwinding machine 3 via the sheet feed roller 4 (a part slightly behind the front end Se) is gripped and fixed by the transport chuck 50. The piston rod 52a of the chuck driving cylinder 52 is protruded to move the transport chuck 50 from the standby position shown by the solid line in FIG. 10 as shown by the imaginary line in FIG. The opening / closing chuck portion of the receiving / fixing chuck 60 is closed by lowering the tip Se of the receiving chuck 60 straight down to a position where the receiving / holding chuck 60 can be gripped by the direction along the female parting surface 14. Opening the section, the leading end Se of the sheet S with the picture is transferred to the receiving and fixing chuck 60 side. Straight raise the transfer chuck 50 draws 52 of the piston rod 52a along the female parting surface 14. This gives 1
The shot-equipped sheets S are supplied onto the female parting surface 14 (sheet supplying step).

After the painting sheet S is supplied onto the female parting surface 14, the clamper 20 'is advanced to the female parting surface 14 as shown in FIG. The sheet S is pressed against the parting surface 14 by the clamper 20 'and fixedly held (clamping step).

After the completion of the clamping step, the picture sheet S is cut in the width direction by the cutter 55 to obtain a single sheet for the current shot (sheet cutting step). ′, And is moved in a non-contact manner by the radiant heat at the sheet heating position (the position where it is brought into contact with the clamper 20 ′ as shown in FIG. 12). While being softened, vacuum suction is performed by vacuum suction means including a vacuum suction hole 15 opening in the female mold cavity 13 and the like.
The film is stretched so as to adhere along 3 (stretching step).

[0023]

However, as described above, the painted sheet S is removed from the female cavity 13 by vacuum suction.
When stretched to adhere along, the decorative laminated product P to be obtained has an undercut portion Pu,
In particular, the undercut end faces 13u, 13 of the painted sheet S
The part wrapped around the u side is extremely elongated, so-called poor pattern elongation occurs, or in severe cases, it becomes too thin to cause wrinkles or tears (E in FIG. 12).

Therefore, the female mold 12 is then advanced toward the male mold 30 and the male mold 30 and the female mold 12 are clamped to form a molding cavity between the two molds 12 and 30 (mold). After the tightening step), a resin in a fluid state is injected and filled into the molding cavity, and the injection resin molded body Pa and the painting sheet S are laminated and integrated (injection molding step). After being completely solidified, the female mold 12 is retracted to its original position, the male and female molds 12 and 30 are opened (opening step), and the slide core 1 is opened.
2B and 12B are retracted in the direction (vertical direction) in which the opening of the female mold cavity 13 is expanded (see FIG. 9 showing an extraction process of an embodiment described later), and the decorative laminate product P obtained in the female mold cavity 13 is removed. Even if it is taken out (usually taken out in a state of being attached to the male mold 30), the taken-out decorative laminate product P is stretched, wrinkled,
Since it is broken, it becomes a defective product.

As one measure for solving the above-mentioned problems, for example, a separate mold for vacuum suction for performing the stretching step is provided, and the prepainted sheet is preformed in this mold, It is conceivable to set the preformed painting sheet (having a shape substantially along the female mold cavity) in the female mold cavity to perform the injection molding step.

However, in the above-mentioned method, a vacuum forming die is separately required, and a troublesome process of transferring a prepainted sheet with the forming die to a female mold cavity is required. It is not a good measure, and the shape of the sheet with the picture collapses at the time of transfer etc.
Since it may be deformed, it cannot be said that the occurrence of defective products can be reliably prevented.

The present invention has been made in order to solve the conventional problems as described above, and an object of the present invention is to provide a decorative laminated product having an undercut portion, by which pattern elongation, wrinkling, tearing, and the like can be prevented. An object of the present invention is to provide a method and an apparatus for simultaneous painting by injection molding, which can be efficiently produced without causing any problem.

[0028]

In order to achieve the above-mentioned object, an injection molding simultaneous painting method according to the present invention is a method for obtaining a decorative laminated product having an undercut portion. A sheet supply step of supplying a painted sheet on a female parting surface provided with a slide core for forming an undercut portion, and a clamping step of pressing and holding the painted sheet against the female parting surface And a stretching step of stretching the painted sheet by vacuum suction and extending along the female mold cavity, and injecting a resin in a fluid state from the male mold side into a molding cavity formed between the female mold and the male mold. Before the stretching step, the portion of the painted sheet to be bonded and laminated is convex toward the female mold cavity side, and is filled with the female mold cavity. The angle between along allowed is to partially undercut edge of the undercut edge and the decorative sheet is characterized in that the preformed advance to be equal to or less than 90 degrees that.

More specifically, prior to the start of the stretching step, the painted sheet is preliminarily formed so as to be convex toward the female mold cavity. In other words, in the conventional injection molding simultaneous painting method and apparatus shown in FIGS. 10 to 12 described above, the painting sheet S forms a flat surface parallel to the clamper 20 until the start of the stretching process. In the method of the present invention, a portion of the painted sheet S to be bonded and laminated is formed in a convex shape by the start of the stretching step.

In the conventional injection molding simultaneous painting method and apparatus, as shown in FIG. 11, before the stretching step is started, the undercut end face 13u of the female mold cavity 13 and the undercut end face 13u of the painted sheet S are removed. Is formed at an obtuse angle (here, about 120'-130 degrees), but in the present invention, the undercut end face 13u and the underside of the painted sheet S are An angle β (see FIGS. 4 and 5 showing an embodiment to be described later) formed by a portion Su to be aligned with the cut end surface 13u is set to be 90 degrees or less.

In a further preferred embodiment, the temporary molding is performed by:
The temporary forming is performed by using a clamping unit used in the clamping step, and more preferably, the painting sheet is sucked and held by the clamping unit. In addition, the temporary forming may be performed using not only the clamp means but also, for example, a sheet supply means or a hot plate for heating and softening the painted sheet.

On the other hand, an injection molding simultaneous painting apparatus according to the present invention is for carrying out an injection molding simultaneous painting method for obtaining a decorative laminated product having the undercut portion.
Basically, a female type and a male type provided with a slide core for forming the undercut portion, sheet supply means for supplying a painted sheet on a female parting surface, and a female type Clamping means for pressing and holding against the bearing surface, sheet stretching means for stretching the painted sheet along the female mold cavity, and the male mold in a molding cavity formed between the female mold and the male mold. And resin injection means for injecting and filling a resin in a fluid state from the side, before stretching the painted sheet by the sheet stretching means,
A portion of the painted sheet to be bonded and laminated is projected toward the female mold cavity side, and an undercut end face of the female mold cavity and a part of the painted sheet to be aligned along the undercut end face. And a provisional sheet forming means for provisionally forming the sheet in advance so that the angle formed is 90 degrees or less.

[0033] The sheet temporary forming means is preferably provided in the clamp means, and more preferably, a vacuum suction hole for sucking and holding the picture sheet is formed in the clamp means. The means may be provided on a sheet supply means or a hot plate, in addition to the clamp means,
Furthermore, it may be separately provided as an independent member. However, in this case, the cost of the apparatus is increased, and a step of transferring a temporarily formed painting sheet is indispensable, and the productivity is reduced.

In a preferred embodiment of the method and apparatus for simultaneous painting by injection molding according to the present invention having the above-described structure, before the start of the stretching step, the laminate of the painted sheets is laminated using a clamping means or the like. The part to be formed is preliminarily molded so as to be convex toward the female mold cavity side,
The angle between the undercut end surface of the female mold cavity and the portion of the painted sheet that should be along the undercut end surface is set to 90 degrees or less.

As described above, by temporarily forming the painted sheet before the start of the stretching step, even if the decorative laminated product to be obtained has an undercut portion, the painted sheet can be moved along the female mold cavity by vacuum suction. During the stretching step of stretching to make close contact, the amount of stretching of the painted sheet, particularly the part wrapped around the undercut end face side, is significantly reduced as compared with the case of the above-described conventional method apparatus, and as a result, In addition, drawbacks such as pattern elongation, wrinkling, and tearing are less likely to occur on the painted sheet, and the occurrence of defective products is suppressed.

Further, by providing the temporary forming means in the clamping means or the like, a troublesome process of transferring the painted sheet is not required, thereby improving the productivity and preventing the collapse of the shape of the painted sheet and undesired deformation. it can. In the simultaneous injection molding painting apparatus of the present invention, the male and female molds are made of metal such as iron or ceramics, and small holes (vacuum suction holes, etc.) for vacuum suction or compressed air supply as necessary. Is provided. In addition, the female mold is provided with a slide core for forming an undercut portion of the decorative laminated product to be obtained.

Further, the female mold is constituted by an aggregate of a plurality of divided parts (in a so-called nested structure), a slit-like gap is formed between adjacent divided parts, and this gap is used as a vacuum suction hole to perform vacuum suction. May be performed. The male mold is provided with a runner for injecting the resin in a flowing state and a required gate. The number, position, shape and the like of the gates can be freely set in consideration of the shape and the like of the product to be obtained.

As the sheet supply means, usually, a long strip-shaped painted sheet (sheet roll) wound up in a roll shape
Are sequentially unwound from the leading end side by one shot, and one shot of the leading side of the unwound painting sheet is transported onto the female parting surface. An unwinding system (roll / roll system, illustrated) in which a single shot of the long strip-shaped picture sheet wound up is unwound by an unwinder from the upstream of the female die and wound up by a winder at the downstream of the female die. Abbreviated), or an unwinder, a transport chuck, as shown in FIG.
Having a receiving fixed chuck, gripping the vicinity of the front end portion of the long strip-shaped painted sheet unwound from the unwinder with the transport chuck and supplying one shot thereof to the female parting surface, The leading end of the sheet is received and fixed by the receiving and fixing chuck, and in this state, the painted sheet is pressed and held on the female parting surface by the clamping means, and then the painted sheet is located upstream of the clamping means. And a transport chuck system in which the sheet is cut in the width direction to form a single sheet, and any of the transport systems may be employed.

Further, as a driving means for transferring the transfer chuck or the like, an endless annular chain or the like can be used in addition to the fluid pressure cylinder. Further, a clamping means is provided to press and hold the picture sheet against the female parting surface. As the clamping means, a holding plate or the like having a frame shape or a girder shape in plan view can be used, and its driving is performed by using a molding driving force such as a mold clamping operation or by using the power of an ejector pin driving mechanism. And by separately providing a driving means such as a fluid pressure actuator.

In a preferred embodiment, the clamping means is provided with a convex portion having a shape conforming to the surface shape of the decorative laminated product to be obtained, as a temporary forming means for temporarily forming the painting sheet. For clamping means,
A vacuum suction hole is provided for sucking and holding (temporarily forming) the painted sheet.

In another preferred embodiment, a hot platen is provided for heating and softening the painted sheet when it is stretched. As the hot plate, a non-contact heating method using infrared radiation is preferable, but a contact method using heat conduction (diffusion) can also be used.

On the other hand, the painting sheet used in the method apparatus of the present invention comprises a base sheet and a decorative layer laminated thereon, and is used as a final product while the base sheet is in close contact with the molded article. After the laminated sheet (laminated sheet) or the painted sheet is once integrated with the molded article, the base sheet (support sheet) is peeled off, leaving only the decorative layer (transfer layer) on the molded article side. Any of the transfer sheets can be used.

In the case of the laminated laminated sheet, a thermoplastic resin such as polyolefin resin such as polyethylene and polypropylene, polyvinyl chloride, acrylic resin, polystyrene, ABS resin, polycarbonate resin and polyester resin is used as the base sheet. Can be. The thickness of the base sheet is usually about 20 to 500 μm. As the decorative layer, a printed pattern, colored or transparent coating, a metal thin film, or a functional layer such as a hard coating film, an antifogging paint, or a conductive layer can be used.

In the case of the transfer sheet, the transfer layer composed of a pattern layer or the like once formed on the releasable support sheet is transferred to another transfer target. A release layer may be provided according to the conditions, and the transfer layer includes a release layer, a decorative layer, an adhesive layer, and the like, and layers other than the decorative layer are selected as necessary. The decorative layer is selected from a pattern layer, a metal thin film layer (part or entire surface) or a functional layer such as a hard coating film, an anti-fog coating film, or a conductive layer. The support sheet is preferably a flexible thermoplastic resin film such as a polyamide resin such as nylon 6 or nylon 66, a polyolefin resin such as polyethylene or polypropylene, or polyvinyl chloride, or a laminate thereof.

As the resin for injection molding, ABS (acrylonitrile-butadiene-styrene copolymer) resin,
Thermoplastic resins such as polystyrene, polyvinyl chloride, acrylic resin, and polycarbonate resin that have been heated and melted to be in a liquid or fluid state, or two-pack curable and catalyst-curable resins such as urethane resins and polyester resins For example, an uncured liquid, such as uncured liquid, can be made of a material that is conventionally known for simultaneous painting with injection molding, and is selected according to the required physical properties of the product, cost, and the like.

[0046]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 9 show an embodiment of a simultaneous painting apparatus for injection molding according to the present invention, in which parts corresponding to those of the above-described conventional apparatus 10 'shown in FIGS. Is attached. The decorative laminated product P to be obtained by the simultaneous injection molding painting apparatus 10 of the present embodiment is the same as that manufactured by the conventional apparatus 10 ′, as shown in FIG. It has an undercut portion Pu whose surface is inclined inward, and a sheet S (laminated sheet) with an image is bonded and laminated on the surface (including the undercut portion on the side end surface) of the injection resin molded body Pa.

Here, as the above-mentioned painted sheet S, here, a base sheet made of acrylic resin (having a thickness of 125 μm)
And a decoration layer (acryl resin and vinyl chloride-vinyl acetate copolymer 1:
A 1% by weight mixture of a binder, a pattern layer of an ink comprising titanium white, carbon black, red iron oxide, a pigment composed of graphite and ultramarine blue) and an adhesive layer (vinyl chloride-vinyl acetate copolymer). , The base material sheet is injection molded resin P
A laminated sheet (laminated sheet) used as a final product while being tightly integrated with a is used.
The decorative layer (pattern layer) has a wood grain pattern formed by combining three colors of a pattern plate, and the adhesive layer has a gravure solid printing plate (screen depth of 60 μm) having a screen ruling of 40 lines / cm.
m) twice (by two-color gravure printing) to form a layer having a thickness of 2 μm.

The simultaneous injection-molding and painting apparatus 10 of the present embodiment also has a female mold 12 and a male mold 30 having an uneven shape corresponding to the decorative laminate product P to be obtained, and the female mold 12 is not shown. However, the bottom (the left end side in the figure) is fixed to the movable platen, and moves in the horizontal direction (X direction in FIG. 1) by the ram of the fluid pressure cylinder, in other words, in the direction approaching and separating from the male mold 30. It is made to move.

In the present embodiment, the female die 12 is movable and moves in the horizontal direction as described above. However, the present invention is not limited to this. It is also possible to adopt a form in which the female dies are vertically opposed to each other and one of them (in this case, the female dies are usually moved) in the vertical direction.

The female mold 12 is composed of a main body 12A and a slide core 1 slidably disposed vertically above and below the right end (the male mold 30 side) of the main body 12A (Z direction in the figure).
2B, 12B, and the main body 12A and the slide cores 12B, 12B form a cavity 13 corresponding to the decorative laminated product P to be obtained. Of the cavities 13, the slide cores 12B, 12B
B, the upper and lower cavities 13 on the right end side
The inclined surfaces (undercut end faces) 13u, 13u inclined in the direction to narrow the opening of the decorative laminate product P are portions forming the undercut portions Pu, Pu of the decorative laminated product P.

In the cavity 13, a large number of vacuum suction holes 15, 15,... For vacuum suction are opened in order to extend the painting sheet S along the cavity 13. , 15, ... are connected to a vacuum source (not shown) including an external vacuum pump and the like via a vacuum suction passage 18 and a conduit 19.

On the other hand, although not shown, the male mold 30 is fixed to a fixed plate on which a nozzle of an injection molding machine is mounted. A convex core portion 31 corresponding to the shape is provided, and a runner 32 for injecting the molten resin and a gate 33 connected to the runner 32 are provided inside the convex core portion 31.

In the female mold 12, a parting surface 34 including the convex core portion 31 of the male mold 30 and a pressing surface portion 20a of the clamper 20 having the convex portion 25 described later sandwich the picture sheet S. A parting surface 14 having a concave portion 14a to be fitted and fitted is formed.

In addition to the above, the female mold 12 is supplied with the supplied one-shot picture sheet S on the parting surface 1.
A rectangular frame-shaped or cross-gear-shaped clamper 20 as viewed from the X direction is provided as shown in FIG. The clamper 20 can be moved forward and backward in a direction perpendicular to the parting surface 14 (Z direction in the figure) by driving means (not shown) via four sliding rods 24 connected to four corners thereof. Has become.

The male mold 30 as a sheet temporary forming means is provided on both right and left sides of the clamper 20.
The convex portions 25, 25 having substantially the same outer shape as the cross-sectional outer shape of the convex core portion 31 (the cross-sectional outer shape of the concave portion 14a of the female die 12 and the decorative laminated product P to be obtained) are provided. The projections 25, 25 are protruded toward the female mold cavity 13. The sheet pressing surface 20 a including the projections 25 has vacuum suction holes 26, 26, for sucking and holding the painting sheet S. Are continuously arranged at regular intervals. As shown in FIG.
As shown in FIG. 5, a vacuum suction passage 27 is formed, and the vacuum suction holes 26 are formed in the vacuum suction passage 27 and a flexible hose 28 connected thereto.
Via an external vacuum pump (female mold 12)
Of the vacuum suction holes 15, 15,...)
It is connected to the.

On the other hand, above the female mold 12 (on the upstream side when viewed in the sheet supply direction), a roll for supplying a painting sheet (laminated sheet) S on the parting surface 14 of the female mold 12 is provided. Discharge machine 3, a pair of feed rollers (nip rollers) 4, guide rollers 5, a transport chuck 50 that can be opened and closed and held.
Are arranged. The transport chuck 50 is a leading end portion Se of the picture sheet S unwound from the unwinding machine 1 loaded with the long strip-shaped picture sheet (sheet roll).
The transfer chuck 50 grips the vicinity and conveys the parting surface 14 of the female mold 12 from the top to the bottom and near the lower end thereof.
2 from the standby position indicated by the solid line in FIG. 1 by the chuck driving cylinder 52.
4 and the clamper 20 (Z direction = vertical direction).

The unwinding machine 3, the feed roller 4, the guide roller 5, and the chuck driving cylinder 52 are mounted on the female mold 12 via supporting members (not shown), respectively. The male mold 30 can be moved toward and away from the male mold 30.

Below and between the male and female molds 12 and 30 (on the downstream side when viewed in the sheet supply direction), a receiving / fixing chuck 60 of an openable / closeable type is disposed. The receiving and fixing chuck 60 is for receiving and temporarily holding and fixing the front end portion Se of the picture sheet S conveyed by the conveying chuck 50.
Are fixedly mounted on a support member (not shown) attached to the first member.

In the vicinity of the upstream end of the female mold 12, the painting sheet S supplied on the female mold parting surface 14 after the clamping step is applied for one shot upstream of the clamper 20. A cutter 55 is provided as a sheet cutting means for cutting into single sheets.

Further, a hot platen 40 for heating and softening the painted sheet S is provided for performing preforming. As shown in FIG. 3, the hot platen 40 has a sectional outer shape (male mold 30) of the temporary forming convex portion 25 provided on the clamper 20.
And a sheet heating surface portion 40a having a cross-sectional shape that is substantially the same as the convex core portion 31, the concave portion 14a of the female mold 12, and the cross-sectional shape on the back side of the decorative laminated product P to be obtained. Driving means (not shown) inserts between the dies from a standby position outside the male and female forming dies, and heats the sheet S at the sheet heating position (as shown in FIG. 7). (The position where the sheet heating surface portion 40a is inserted into the clamper 20 which is pressed and fixed and held) to heat and soften the painted sheet S. In this case, the hot platen 40 uniformly heats each part of the painted sheet S from an equal distance by a non-contact heating method using infrared radiation.

In performing simultaneous injection molding painting with the simultaneous injection molding painting apparatus 10 of the present embodiment having the above-described configuration, first, the painting sheet S is supplied onto the female parting surface 14. , The leading end S of the picture sheet S unwound from the unwinder 3 via the sheet feed roller 4
1 (slightly behind the front end Se) is gripped and fixed by the transport chuck 50, and the piston rod 52a of the chuck driving cylinder 52 is projected so that the transport chuck 50 is shown by a solid line in FIG. From the standby position, as shown by the imaginary line in the figure, the leading end Se of the painted sheet S being gripped is
And lower it straight down in the direction along the female parting surface 14 until it can be gripped by
0 is closed and the transfer chuck 5 is closed.
Open the opening / closing chuck part of the sheet S and move to the front end Se of the sheet S with the picture.
Is transferred to the receiving fixed chuck 60 side, and thereafter, the piston rod 5 of the chuck driving air cylinder 52 is moved.
2a is drawn in, and the transport chuck 50 is raised straight along the female parting surface 14. As a result, the one-shot picture-added sheet S is supplied onto the female parting surface 14 (sheet supply step).

After the painting sheet S is supplied onto the female parting surface 14, the clamper 20 is advanced to the female parting surface 14 as shown in FIG. Vacuum suction of the sheet S is performed through the vacuum suction holes 26, 26,. At this time, by appropriately lowering and loosening the transport chuck 50 gripping the upstream end of the painted sheet S, the painted sheet S (the central portion Sa to be bonded and laminated) is almost stretched. Without
As shown in FIG. 5, the clamper 20 is held by being attracted to the sheet pressing surface portion 20a of the clamper 20. in this way,
The painted sheet S is sucked and held by the clamper 20 provided with the convex portions 25, 25, so that the portion Sa of the painted sheet S to be bonded and laminated is temporarily convex to the female mold cavity 13 side. It is molded (temporary molding step).

Then, the clamper 20 holding the painting sheet S by suction is further advanced toward the female mold 12 so that the painting sheet S is brought into contact with the sheet pressing surface 20a of the clamper 20 as shown in FIG. The female parting surface 14 is pressed and fixed and held so as to be sandwiched between the parting surface 14 (clamping step). In this clamping step, the female cavity 1
3 undercut end surfaces 13u, 13u and the undercut end surfaces 13u, 13u,
The angle β between the parts Su and Su to be made along 3u
Is set to be 90 degrees or less.

After the completion of the clamping step, the picture sheet S is cut in the width direction by the cutter 55 to obtain sheet sheets for the current shot (sheet cutting step), and the hot platen 40 is moved to the sheet heating position. (As shown in FIG. 7, the painted sheet S is moved to the position where the sheet heating surface portion 30a is inserted into the clamper 20 which presses and holds the painted sheet S against the female parting surface 14). While being softened by heating, vacuum suction is performed by vacuum suction means including a vacuum suction hole 15 opened in the female mold cavity 13 and the like, and the painted sheet S is stretched so as to be in close contact with the female mold cavity 13 (stretching). Process).

Here, in this embodiment, before the stretching step is started, the painted sheet S is adsorbed and held on the clamper 20 provided with the protruding portions 25, 25, so that the adhesive lamination of the painted sheet S is performed. A portion Sa to be formed is preliminarily formed so as to protrude toward the female mold cavity 13 side, and the undercut end surfaces 13u, 13u of the female mold cavity 13 and the undercut end surfaces 13u, 13u of the painting sheet S are formed. Part S to be aligned with
Since the angle between u and Su is set to be equal to or less than 90 degrees, the drawing sheet S is stretched so as to be closely adhered along the female mold cavity 13 by vacuum suction. In particular, the amount of stretching of the portion wrapped around the undercut end surfaces 13u, 13u side is greatly reduced as compared with the case of the above-described conventional method apparatus, and as a result, the pattern-elongation, wrinkling, and tearing of the painted sheet occur. And the like are less likely to occur, and the occurrence of defective products is suppressed. In addition, the provision of the projections 25, 25 as the sheet temporary forming means in the clamper 20 eliminates the need for a troublesome process of transferring the painted sheet, thereby improving the productivity and improving the shape of the painted sheet. Desired deformation can be prevented.

After the completion of the stretching step as described above, the female mold 12 is advanced to the male mold 30 side as shown in FIG. 8, and the male mold 30 and the female mold 12 are clamped. After forming the molding cavity 35 between the molding dies 12 and 30 (mold clamping step), the molding cavity 35 is filled with a flowable resin Pa, and the injection resin molding Pa
And the painted sheet S are laminated and integrated (injection molding step). After the injection resin molded body Pa is completely solidified, the female mold 12 is retracted to the original position, and the male and female molds 1 are formed.
Opening of molds 2 and 30 (opening process) and FIG.
As shown in the figure, the slide cores 12B, 12B are retracted in a direction (vertical direction) in which the opening of the female mold cavity 13 is expanded, and the decorative laminated product P (semi-finished product) obtained in the female mold cavity 13 is taken out. (Ordinarily, the decorative laminate product P is taken out in a state of being attached to the male mold 30). Thereafter, the decorative laminated product P is detached from the male mold so as to protrude with an ejector pin or the like. Finishing such as trimming is performed to obtain a decorative laminated product P as a finished product.

[0067]

As will be understood from the above description, according to the present invention, a decorative laminated product having an undercut portion can be efficiently produced without causing pattern elongation, wrinkling, tearing, etc. Injection molding simultaneous painting method and apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing one embodiment of an injection molding simultaneous painting apparatus according to the present invention.

FIG. 2 is a perspective view showing a clamper used in the apparatus shown in FIG.

FIG. 3 is a perspective view showing a hot plate used in the apparatus shown in FIG. 1;

FIG. 4 is a partially enlarged longitudinal sectional view for explaining a temporary forming step of the apparatus shown in FIG. 1;

FIG. 5 is a partially enlarged longitudinal sectional view showing a temporary forming step of the apparatus shown in FIG.

FIG. 6 is a partially enlarged longitudinal sectional view showing a clamping step of the apparatus shown in FIG. 1;

FIG. 7 is a partially enlarged longitudinal sectional view showing a sheet heating softening step and a stretching step of the apparatus shown in FIG.

FIG. 8 is a partially enlarged longitudinal sectional view showing an injection molding process of the apparatus shown in FIG.

FIG. 9 is a longitudinal sectional view showing a mold opening step and a removal step of the apparatus shown in FIG.

FIG. 10 is an overall configuration diagram showing an example of a conventional simultaneous injection molding painting apparatus.

11 is a partially enlarged longitudinal sectional view showing a clamping step of the conventional apparatus shown in FIG.

FIG. 12 is a partially enlarged longitudinal sectional view showing a sheet heating softening step and a stretching step of the conventional apparatus shown in FIG.

13A and 13B show a decorative laminated product having an undercut portion to be obtained by the injection molding simultaneous painting method and apparatus of the present invention, wherein FIG. 13A is a partially cutaway perspective view, and FIG. 13B is a partially enlarged longitudinal sectional view.

[Explanation of symbols]

 P Decorated laminated product Pu Undercut section S Painting sheet 10 Injection molding simultaneous painting apparatus 12 Female mold 12A Main body section 12B Slide core 13 Female mold cavity 13u Undercut end face 14 Female mold parting surface 15 Vacuum suction hole 20 Clamper 25 Convex part (Sheet temporary forming means) 26 Vacuum suction hole 30 Male type

Claims (6)

[Claims] An injection molding simultaneous painting method for obtaining a decorative laminated product having an undercut portion, wherein the slide molding for forming the undercut portion is provided on a female parting surface. A sheet supply step of supplying a painted sheet, a clamping step of pressing and holding the painted sheet against the female parting surface, and a stretching step of stretching the painted sheet by vacuum suction and extending along the female mold cavity, An injection molding step of injecting and filling a resin in a flowing state from the male mold side into a molding cavity formed between the female mold and the male mold, and The part to be bonded and laminated becomes convex to the female mold cavity side,
In addition, injection molding is performed in advance so that an angle between an undercut end surface of the female mold cavity and a portion of the painted sheet to be formed along the undercut end surface is 90 degrees or less. Simultaneous painting method. 2. The simultaneous injection molding and painting method according to claim 1, wherein the temporary molding is performed by using a clamping means used in the clamping step. 3. The simultaneous injection molding and painting method according to claim 2, wherein the temporary molding is performed by causing a painting sheet to be sucked and held by the clamping means. 4. A simultaneous injection-molding and painting apparatus for obtaining a decorative laminated product having an undercut portion, comprising: a female mold and a male mold provided with a slide core for forming the undercut portion; Sheet supply means for supplying the sheet onto the female parting surface, clamping means for pressing and holding the painted sheet against the female parting surface, and sheet stretching means for extending the painted sheet along the female cavity And a resin injection means for injecting and filling a resin in a flowing state from the male mold side into a molding cavity formed between the female mold and the male mold, and stretching a painted sheet by the sheet stretching means. Prior to this, the portion of the painted sheet to be bonded and laminated is projected toward the female mold cavity, and the undercut end face of the female mold cavity and the painted sheet are A sheet temporary forming means for temporarily forming the sheet so as to form an angle of 90 degrees or less with a portion to be formed along the end face of the undercut. 5. The simultaneous injection molding and painting apparatus according to claim 4, wherein said sheet temporary forming means is provided in said clamping means. 6. The simultaneous injection molding and painting apparatus according to claim 5, wherein a vacuum suction hole for sucking and holding the painting sheet is formed in the clamp means.