JP3235140B2 - Manufacturing method of three-dimensional laminated molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method of manufacturing a three-dimensional molded product used for an illuminated switch, a dial, a display panel, etc., in which characters and marks are raised by an internal lamp light during operation. Partial transmission of light to clarify the design,
Switches and display panels for clearly identifying display contents from others are widely used in various electric and electronic devices such as automobiles, audio equipment, and VTRs. In particular, recently, with emphasis on design, display panels and switches having a three-dimensional shape rather than a flat or gentle curved surface have been demanded.

[0002]

2. Description of the Related Art Print coating, in which only characters and panels are light-transmitting and others are light-shielding, is easily performed by multi-layer printing or masking coating on products having flat or gentle curved surfaces, and has a three-dimensional shape. Even in the case of a product, if the printed painted portion has a convex shape, it can be processed by a post-processing method such as tampo or pad printing.

However, in the case of a three-dimensional product having irregularities, it is difficult to perform a post-processing method. A painting molding method that is integrated with the resin that is inserted and injection molded,
A molding transfer method of transferring only a coating film to a product is used.

Although a relatively small shape can be formed simultaneously with injection molding by using a flat sheet or film, wrinkles are generated in the sheet or film when processing from a flat state when the shaping amount is large. It was difficult to break, break or cut.

[0005] As a means for solving the problem, there is also known a method in which a sheet or film is formed into a product shape in advance, or a sheet or film is thermoformed in a mold to conform to the shape, and then injection molded.
However, when thermoforming a sheet or film according to its shape, the sheet or film is heated to a temperature higher than the softening temperature of the base resin of the sheet or film. In order to be disturbed, collapsed or discolored, it is necessary to select a special ink or stamping foil, which has a drawback that the selection range is limited.

In order to make up for the drawbacks of thermoforming, there is an example of using a sheet or film which can be cold drawn.
There is a drawback that the processing range is narrow and processing marks (elongation marks) remain on the sheet or film surface when larger shaping is performed.

[0007]

Means for Solving the Problems The present inventors have intensively studied a method for solving the above-mentioned problems of the conventional method, and as a result, formed a three-dimensional shape in a mold by using a core and a molten resin to be injection-molded. Thus, the present invention has been completed.

That is, the present invention uses a mold having a cushioned core (CC) having a shape in which at least a portion corresponding to a light-transmitting pattern forming portion such as a design or a mark at the center portion protrudes. 0.1-2.0mm thick, light-transmitting flat aromatic polycarbonate resin sheet formed by printing a light-transmitting pattern such as a design or mark
(1) is mounted on the mold, and the core (CC) is subjected to primary molding of the sheet (1) until the protruding portion presses the light transmitting pattern portion of the sheet (1) against the cavity surface. A sheet excluding the pressed portion is formed by injecting the molten thermoplastic resin molding material while holding the pressing and performing the final shaping to the cavity shape of the sheet (1) and the injected thermoplastic resin molding material. 1) This is a method for producing a three-dimensional laminated molded product, which is characterized in that the surface is laminated and integrated.

[0009] As the mold, a jig for mounting the sheet (1) on the core side and the core (CC) fixed to the core side is used. ) Is sandwiched between the mounting jig and the cavity side, and then the sheet (1) is primarily formed by the core (CC),
The core (CC) is movable, and the sheet (1) is
This is a method of manufacturing a three-dimensional laminated molded product, which is mounted by sandwiching C) between a core side retreated to a core side surface and a cavity side.

Further, according to the present invention, the core (CC) is movable independently of its periphery at a central protruding portion thereof, and the primary molding of the sheet (1) is such that the protruding portion of the core is cooperated with the periphery. This is a method for producing a three-dimensional laminated molded product, in which a molten thermoplastic resin molding material is injected with the core (CC) having the same surface, and only the protruding portion is pressed against the sheet (1).

Hereinafter, the present invention will be described. The mold of the present invention, as the core (CC) of the mold core side, at least a cushioned core (C) having a shape in which a portion corresponding to a light-transmitting pattern forming portion such as a design or a mark in the center portion protrudes.
C). This protruding part is made of a molten thermoplastic resin molding material introduced by injection molding.
It closes the gap so that it does not get on, and as a result,
Even if a light-impermeable molding material is used, components such as an illumination switch can be manufactured.

The cushion is for preventing a trace of tight contact of the core from being left on the sheet (1). The cushion may be a soft elastic resin such as rubber or elastomer, for example, chloroprene rubber, fluorine rubber. A spring made of metal or the like; a damper structure using a gas or a liquid, and a compression elastic modulus of about 1 × 10 ³ to 0.5 × 10 ³ k at a temperature of about 40 to 100 ° C.
The range of gf / cm ² is preferred. In addition, urethane rubber having relatively low heat resistance can be suitably used when the temperature of the cushion mounting portion is about 60 ° C. or less.

In the present invention, the sheet (1) is shaped in a mold. For this purpose, the mold is provided with a mechanism for mounting and shaping the sheet (1). Preferably, a jig for mounting the sheet (1) is provided on the core side, a mold in which the core (CC) is fixed to the core side, a movable core (C).
A mold having C), and a mold in which the central protruding portion becomes movable independently of the outside. In any case, since the cavity surface side of the core (CC) is for shaping the sheet (1), it is preferable that the corner portion is formed by a smooth curve.

The sheet (1) of the present invention which is mounted on the mold, shaped, and used for laminating and integrating into a three-dimensional laminated molded product, has a thickness of 0.1 to 2.0 mm, which is pre-printed and painted, and has a light transmitting property. This is a sheet made of an aromatic polycarbonate resin having flat properties.

The sheet used for the aromatic polycarbonate resin sheet may be a light-transmitting ordinary aromatic polycarbonate resin sheet having a thickness of 0.1 to 2.0 mm.
There is no particular limitation. The surface of the sheet may be a glossy smooth surface or a matte surface having fine matte unevenness without gloss. The sheet may be colored to a desired color with a suitable dye or pigment as long as the sheet transmits light.

Further, the sheet (1) has a structure in which an adhesive layer is appropriately formed on the sheet surface on the side integrated with the thermoplastic resin for injection molding from the viewpoint of adhesiveness with a molding material resin used for injection molding. It is preferred that As an example of the adhesive layer, the thermoplastic resin molding material is polycarbonate (PC), PC
/ Polyester resin (PES) composition, PC / ABS resin composition, PC / polyamide resin (PAD) composition, other PC
In the case of a resin composition containing PC as one of the main components (PC alloy), there is no adhesive layer; the thermoplastic resin molding material is an acrylic resin such as polymethyl methacrylate (PMMA), polystyrene (PS), methyl methacrylate. Styrene-based copolymer (MS), acrylonitrile-styrene copolymer (AB
In the case of (S) or the like, an acrylic resin layer is formed;
In the case of polyvinyl chloride or other general-purpose applications that do not require heat resistance, an example in which an EVA-based resin layer is formed is exemplified.

On the sheet (1), a light-shielding portion having a design such as a light-transmitting character or mark at substantially the center of the light-shielding portion is formed. This method is not particularly limited, such as conventionally known silk screen printing, hot stamping, coating, sputtering, and plating. The characters or marks are not particularly limited, such as various characters, marks, and designs. In addition, if the characters or marks are naturally light-transmissive, white, clear coloring, or other printed materials such as paints or inks are preferably used.

Here, the binder component of the ink or paint used to form the light-shielding portion may be any of those known for conventional polycarbonate resins, and is not particularly limited. For example, as the binder component, acrylic, acrylic / alkyd, urethane, acrylic / urethane, epoxy, vinyl chloride / vinyl acetate copolymer,
Nitrocellulose and the like. Oxides such as titanium dioxide, red iron and cobalt blue, sulfides such as zinc sulfide, sulfates such as sedimentable barium sulfate, hydrated silicates, silicates such as ultramarine, and ferrocyanines such as dark blue Powders, metal powders such as aluminum powder and zinc powder, and various hydroxides, chromates, carbonates, and phosphates, and brilliant carmine 6 as an organic pigment.
B, azo pigments such as disazo yellow, phthalocyanine pigments such as phthalocyanine blue, nitro pigments such as naphthol yellow, condensed polycyclic pigments such as quinacridone red, and various other organic pigments and dyes are appropriately used.

Printing inks and paints are prepared by mixing these binders, colorants, appropriate solvents, additives and the like.
Light-transmitting characters or marks are formed by coating and drying the sheet (1). When a metal-like appearance is required, a method such as hot stanping or masking a character or mark portion is used, and a method such as sputtering, vacuum deposition, or plating is used. If necessary, under and top are coated.

The sheet (1) on which the light-transmitting characters or marks and other designs and the light-shielding portions are formed as described above is usually placed in a mold cavity for mounting the sheet (1) in the shape or size (cross section). And used as a single piece with the width of the mounting part added to the circumference of the part, or cut into a shape that can be continuously supplied and sequentially collected. The width of the mounting portion is determined by the degree of shaping by the core for each product shape. If the shape of the sheet (1) is large or cold, the cross-sectional area of the mounting part should be If it is large, it is preferable to make it wider.

The thermoplastic resin molding material of the present invention can use either light-transmitting or light-impermeable, and is not particularly limited, and is appropriately selected depending on the required performance, shape, cost, and the like of the product. In addition, a known condition range of the resin material to be used is applied to the injection molding conditions and the like.

Specific molding materials include PC, PC / PBT, P
PC / PES compositions such as C / PET, PC / PCTA, PC / PCTG, PC / ABS,
PC / polyphenylene ether (PPE) / PES composition, PC / PA
Compositions, PC / PES / PA compositions, other PC alloys; PMMA
Acrylic resin such as; PS, MS, AS, ABS and other styrene resins; PPE / PES, PPE / PA, PPE / PES, other PPE alloys; Polyacetal resin and its composition; Nylon-6
(PA6), nylon-66 (PA66), nylon-6,10 (PA610),
PA such as nylon-12 (PA12), nylon-MXD6; PET,
PBT such as PBT, 1,4-hexanediol / terephthalic acid / isophthalic acid copolymer (PCTA), 1,4-hexanedimethanol / ethylene glycol / terephthalic acid copolymer (PCTG)
ES; PVC and the like are exemplified, and engineering plastics and alloys thereof are particularly suitable.

Next, in order to facilitate understanding of the present invention,
An example will be described with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a manufacturing process of a light switch with a mark according to the present invention. A sheet (1) is mounted on a mold, and a primary core is provided with a movable core (CC) having a cushion and a central portion protruding. After shaping, the molten molding material is injected into the cavity and
FIG. 4 is a view schematically illustrating a state in which the final shaping of (1) is performed and a three-dimensional laminated molded product that is laminated and does not enter a portion covered by a protrusion of the core (CC) is manufactured.

The reference numerals in FIG. 1 are respectively: a polycarbonate resin sheet which has been printed and painted in advance, the design of which is light-transmitting and the other portions are light-shielding, 2: injection resin,
10: cavity side, 20: core side, CC: movable core, CW: protrusion core (core protrusion), 21: runner,
22: Indicates a gate, and corresponding parts in b, b ', and c indicate the same one.

In FIG. 1A, a sheet (1) is mounted on the mold cavity side, and the sheet (1) is sandwiched between the core side and the cavity side where the movable core (CC) has retreated to below the core side surface. Be attached.

Next, as shown in b, the movable core (C
C) is advanced by the protruding portion until the sheet (1) is pressed against the cavity side to perform primary shaping of the sheet (1). In b ', the sheet (1) is pressed against the cavity side while the movable protrusion (CW) of the movable core (CC) is retracted until it becomes flush with the outside. After moving forward to form the primary shape of the seat (1),
The outside is in a state of retreating to a predetermined core position except for the protrusion (CW).

Next, in the step c, after the mold clamping pressure is increased to the normal pressure, the molten thermoplastic resin is injected to perform the secondary molding (final molding) of the sheet (1), and to form the sheet (1) with the molded article main body. After the lamination integration and formation of the molded article main body and the injection resin is cooled, the molded article is taken out. Sheets are usually included in manufactured parts
(1) Since the portion sandwiching is overhanging, it is cut into a product.

Although not shown in the drawings, the sheet
Using the mounting jig of (1), the sheet (1) was mounted by the mounting jig by the operation of closing the mold, and subsequently, the sheet was normally fixed to the core side surface by the mold closing operation. It is also preferable that the sheet (1) is subjected to primary molding by the core (CC) and a normal mold clamping pressure is applied, and then a molten thermoplastic resin molding material is injected.

The present invention has been described with reference to the drawings. In the method for producing a three-dimensional laminated molded product of the present invention, it is preferable that the shaping amount of the first step by the core (CC) is selected from a range of 50% or less as an area increase rate or a simple elongation of the sheet (1). Yes, especially when preheating sheet (1)
% In the range of about 20%, and preferably in the range of about 20% or less in a cold state. In the present invention,
The sheet (1) generated by the primary molding due to the introduction of the molten resin immediately after the primary shaping easily loses the surface elongation traces, etc., but when the shaping amount exceeds the upper limit, it occurs at the time of shaping. The resulting stretch marks remain after forming the molded article, which is not preferable. Further, as the shape of the mold, especially the corner angle of the corner portion of the core (CC), is larger, larger shaping is possible, and it is preferable to make the molded product design in this way.

When shaping the sheet (1) with the core,
When the mold clamping pressure is set to normal pressure, the sheet (1)
Molding distortion increases, local elongation and the like are likely to occur, and in particular, a disturbance such as a printed pattern of the local elongation part occurs, and in some cases, deformation of a light-transmitting design part occurs. Sometimes. Therefore, it is preferable to select a mold clamping pressure at which the sheet (1) slides inward due to the shaping force.

[0031]

The present invention will be described below in detail with reference to examples. Example 1 As a mold, it corresponds to FIG. 1 and has a cylindrical illuminating switch component cavity of 38 mmφ in sheet mounting portion, 20 mmφ in cavity cross section, 25 mm in height and 2 mm in thickness, and silicone as a cushion. Using a rubber sheet, a movable core having a protrusion of 10 mmφ at the center, 1.7 mm higher than the periphery, was used.

Using a polycarbonate resin sheet having a thickness of 0.5 mm, a light-transmitting mark was provided at the center, and light-shielding topcoat printing was applied to the other portions. This sheet was punched out into a 38 mmφ disk in accordance with the dimensions of the die mounting portion with a press machine to obtain a mounting sheet (1).

The sheet (1) was placed on the mounting portion on the cavity side, and then the sheet (1) was sandwiched between the core side and the cavity side. Next, the movable core (CC)
The sheet (1) was advanced until the sheet (1) was pressed against the cavity at the protrusion of the core, and the sheet (1) was primarily shaped.

The clamping pressure was increased to the normal pressure used for injection molding, and the opaque polycarbonate resin (Iupilon S
-3000) at a temperature of 290 ° C and a pressure of 1,600 kgf / cm ² , the sheet (1) and the injection resin are laminated and integrated up to 8 mm from the top surface, and the protrusion is only the sheet (1) A product was obtained, and the protruding portion of the PC sheet remaining in the molded product (the portion remaining between the molds) was press-cut to obtain a product. The obtained product had a light-transmitting design in the center of the upper surface, and the design pattern and other portions of the laminated and integrated sheet (1) were not disturbed by shaping.

[0035]

According to the present invention, a flat sheet is formed in a mold to produce a molded product laminated and integrated with an injection molding resin, so that the sheet is formed into a three-dimensional laminated molded product. The step of preforming together is omitted, and the mounting of the sheet in the mold is easy because it is a flat plate.
(1) Since molten resin is introduced immediately after primary molding,
Elongation traces due to the molding of the sheet (1) hardly occur. Further, since the molding material resin does not enter the light-transmitting mark or the part with the above, an opaque molding material can be used, and the degree of freedom in design, performance, and the like is increased.

As a result, compared to the conventional method, it is possible to manufacture a three-dimensional laminated molded product having a design pattern with higher productivity, and it is possible to form a three-dimensional shape which has been difficult in the past. Yes, its industrial significance is great.

[0037]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a manufacturing process of an illuminated switch with a mark.

[Explanation of symbols]

The reference numerals in FIG. 1 are respectively: a polycarbonate resin sheet which has been printed and painted in advance in which the design is light transmissive and the other portions are light-shielded, 2: injection resin, 10: cavity side, 20: core side, CC: movable core, CW: projecting core, 21: runner, 22: gate, b,
Corresponding parts in b 'and c indicate the same parts.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-1-320120 (JP, A) JP-A-62-1201015 (JP, A) JP-A-54-87761 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) B29C 45/14-45/57

Claims (4)

(57) [Claims] 1. A mold having a cushioned core (CC) having at least a portion corresponding to a light-transmitting pattern forming portion such as a design or a mark in a central portion thereof is protruded, and a design or a mark is previously formed in the central portion. A light-transmissive flat aromatic polycarbonate resin sheet (1) having a thickness of 0.1 to 2.0 mm and a light-transmissive pattern formed by printing is mounted on the mold, and the core (CC) is used to attach the sheet. Until the protrusion presses the light-transmitting pattern of the sheet (1) against the cavity surface,
(1) is subjected to primary molding, the molten thermoplastic resin molding material is injected while the pressing is maintained, the final shaping of the sheet (1) into the cavity shape is performed, and the injected thermoplastic resin molding material is injected. Characterized in that they are laminated and integrated on the surface of the sheet (1) excluding the pressed portion. 2. A mold having a jig for mounting the sheet (1) on a core side and having the core (CC) fixed to the core side is used as the mold. ) Is sandwiched between a mounting jig and a cavity side, and then the sheet (1) is primarily formed by the core (CC).
Method for manufacturing the three-dimensional laminated molded product described 3. The sheet according to claim 3, wherein the core (CC) is movable.
2. The method according to claim 1, wherein (1) is mounted by sandwiching the core (CC) between a core side retreated to a core side surface and a cavity side. 4. The core (CC) is movable independently of its periphery at a central projection thereof, and the primary molding of the sheet (1) makes the projection of the core flush with the periphery. Core (C
2. The method according to claim 1, wherein the molten thermoplastic resin molding material is injected with only the protruding portions pressed against the sheet (1).