JPH0572247B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for injection molding a thermosetting clamp as a material and simultaneously painting the same.

To apply decoration at the same time as injection molding, in the case of thermoplastic resin, preform a decorative sheet in the female mold by vacuum forming before injection molding, and then insert the male Molten resin is injected from the mold side, and a painted sheet is attached to the surface of the injected resin.

Such molding is carried out by preparing an injection molding device having a male mold and a female mold, and inserting a paper leaf-like illustrated sheet between the two molds, which has been printed in advance by the operator. Therefore, it is inefficient and has low productivity.

Therefore, a method can be considered in which the strip-shaped sheet is intermittently sent between the two molds and the decoration is carried out continuously. There is a problem in that misalignment between the pattern and the molding surface occurs due to sagging of the patterned sheet. Particularly in the horizontal type, in which the male mold and the female mold are separated in the water direction and the painted sheet is fed vertically, it is difficult to synchronize the design with the molded product body because the painted sheet sag due to its own weight.

The present invention was developed in view of the above problems, and involves continuously feeding a roll-shaped continuous painted sheet with a pattern printed between molds, and performing the painting at the same time as the injection molding of the thermosetting resin. It is an object of the present invention to provide a method for making up at the same time as thermosetting resin injection molding, which enables complete synchronization with the product. The present invention is held between an unwinding roll and a winding roll,
A decorative sheet having at least a pattern made of thermosetting ink is movably faced between a female mold having a molding surface and a male mold having an injection device, and the decorative sheet is provided with a design on either the front side or the back side of the decorative sheet. A frame member that has a suction plate having a ventilation hole spaced apart from the sheet, and that moves together with the suction plate by sandwiching the painted sheet together with the suction plate at a distance from the painted sheet on the other side of the front side or the back side of the painted sheet. The suction plate and the frame member are moved to the regular position relative to the picture on the pictured sheet, and then the pictured sheet is held between the suction plate and the frame member, and then the pictured sheet is sandwiched. Move the suction plate and frame member between the female mold and the male mold by one pitch of the pattern so that the pattern on the painted sheet faces the correct position on the molding surface of the female mold, and then place the female mold and male mold together. Thermosetting resin is characterized in that the thermosetting resin is injected into the cavity between the female mold and the male mold by a male injection device, and the thermosetting resin is heated and molded. This is a method of applying makeup at the same time as resin injection molding.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a finished product molded by the method of the present invention. A painted sheet 2 is attached to the surface of the main body 1 on which the molten resin has been thermoset, and the flowers 10 on the painted sheet 2 are attached to the main body 1. The letter 12 is attached to the convex portion of the illustrated sheet 2, and letters 12 are drawn at the bottom of the illustrated sheet 2.

FIG. 2 is a longitudinal cross-sectional view of an injection molding apparatus M used for carrying out the method of the present invention, in which a male mold 16 fixed to a fixed platen 20 and a movable platen 24 are shown in the lower part.
The movable platen 24 is movable by a pressurizing ram 22, and an ejector 26 is provided adjacent to the movable platen 24. is provided, and this ejector 2
Reference numeral 6 includes a protruding pin (not shown) for ejecting the molded product out of the mold after injection molding.

An injection device 28 is inserted into the center of the fixed platen 20 and the male mold 16, and the molten resin injected from the injection device 28 passes through an injection hole 30 bored in the male mold 16 and enters the female mold 18. Press-fitted into the cavity.

In addition, the illustrated sheet 32 has a male type 16 and a female type 18.
It travels vertically downward between the two, and is held by an unwinding roll 34 located above and a take-up roll 36 located below, and its traveling position is regulated by upper and lower guide rolls 38, 38.

A predetermined pattern is printed at a fixed pitch on the picture sheet 32, and if the pattern is to be printed on the back or for transfer, it is set so that the printed side is on the opposite side to the female die 18, and vice versa, if it is to be printed on the front side, is set so that the printed side faces the female mold side. And the picture sheet 32
In addition to the picture, positioning marks 40 (register mark marks) as shown in Fig. 3 are printed at a fixed pitch. direction) and a vertical line b for determining the position, and these lines a and b may be formed separately.

A frame member 4 is provided above the male mold 16 and the female mold 18.
6 and a suction plate 44 facing this frame member 46 are disposed, and these members 44 and 46 cooperate with each other to sandwich the illustrated sheet 32, and the male mold 16 and the female mold 18
The illustrated sheet 32 is moved between. The frame member 46 has a U-shape and is slidably supported by rails 42 with the lower part open, and two rails 42 are provided vertically on both sides of the female mold 18.

The suction plate 44 also has ventilation holes 5 inside it.
The ventilation hole 50 is connected to a compressed air pump (not shown) through a common guide hole 51, and is moved vertically by a cylinder 52 rotatably held by a frame (not shown).
It is moved in the direction toward and away from the frame member 46 by an air cylinder, an oil cylinder, a servo motor, or the like (not shown). At the top and bottom of the suction plate 44 or the frame member 46, detectors 5 made of phototubes or the like are provided for detecting the marks 40 on the illustrated sheet 32.
It is desirable to provide two detectors 54 for detecting the X direction and two detectors 54 for detecting the Y direction.

Note that a rod member 56 that supports the illustrated sheet 32 is installed oppositely below the female mold 18, and this rod member 5
6 are moved toward and away from each other by an air cylinder (not shown) supported by the movable plate 24. Furthermore, the female mold 1
A ventilation groove 58 for evacuation is bored in the interior of the housing 8 .

A molding method using the apparatus configured as described above will be described below.

First, when the detector 54 detects the horizontal line a of the mark 40 on the sheet, the operation of the servo motor (not shown) for integrally moving the suction plate 44 and the frame member 46 is stopped, and then both members 44, 46 are moved in the Y direction.
46 is moved by a servo motor (not shown),
When the detector 54 detects the vertical line b, the servo motor stops and the suction plate 44 moves to a normal position with respect to the pattern.

Next, the illustrated sheet 32 is placed on the suction plate 44a through the ventilation hole 5 formed in the suction plate 44a of the suction plate 44.
is attached, and the suction plate 44 is moved toward the frame member 46 by the operation of an air cylinder (not shown) to sandwich the illustrated sheet 32 between the two members 44 and 46.

Thereafter, both members 44 and 46 return to their reference positions by the operation of the servo motor, and as shown in FIG.
2 expands, the frame member 46 and the suction plate 44 integrally descend from the reference position along the rail 42 and stop at a predetermined position above the female mold 18. Along with this, the illustrated sheet 32 is unwound by one pitch. Here, since the lower part of the frame member 46 is open, the frame member 46 can surround the female mold 18, and the suction plate 4
4 holds the illustrated sheet 32 and closes the cavity of the female mold 18. At this point, the picture printed on the picture sheet 32 is placed at a regular position (synchronized position) with respect to the molding surface of the female mold 18.

In this state, first open the ventilation groove 58 of the female mold 18.
Vacuum the female mold cavity through the . Note that if the ventilation grooves 58 are not formed on the product surface, vacuum may be drawn from the side of the cavity. Thereafter, compressed air is sent through the vent hole 50 of the suction plate 44 to peel off the sheet 32 from the surface of the suction plate 44a, and the sheet 32 is attached to the molding surface of the female mold 18 as shown in FIG. Here, in the case of deep drawing, that is, when the forming surface of the female mold is deep, the suction plate 4
If a part of the decorated sheet 4 is held by a cylinder or the like (not shown) and moved to the molding surface side of the female mold 18 and then evacuated, the decorated sheet can be preformed without excessive stretching.

In addition, in the above process, the cavity of the female mold 18 is evacuated and then compressed air is sent from the adsorption plate 44 side to attach the painted sheet 32 to the molding surface of the female mold 18. It is also possible to exhaust the air from the ventilation groove 58 while sending the air.

However, in this case, it is necessary to provide a large number of ventilation grooves 58 in the female mold 18. This is due to air remaining in the cavity. On the other hand,
According to the former method, there is no air remaining in the female mold during molding of the illustrated sheet 32, so the ventilation grooves 5
There is no need to provide a large number of 8's. Therefore, traces of the ventilation grooves 58 generated on the surface of the molded product can be reduced.

Thereafter, the suction plate 44 is lifted from the frame member 46 by operation of an air cylinder (not shown), and both members 44 and 46 are moved to the second position by operation of the air cylinder 52.
Return to the reference position shown in the figure. At this time, the illustrated sheet 32 is clamped by the rod member 56 so that the illustrated sheet 32 does not move. Further, the adsorption plate 44 may have a built-in heater to heat the decorated sheet 32 to a temperature below the curing temperature so that vacuum-pressure forming can be easily performed.

Then, as shown in FIG.
2 and unites with the male mold 16, and the molten resin is injected from the injection machine 28. Furthermore, the mold is released and the rod member 56 is separated. In this way, a decorated molded product 1 is obtained in which only the decorated sheet 32 itself or its printing ink is adhered to the surface of the injection molded part 60.

Although the detector 54 first detects the X direction and then the Y direction, it may detect the marks 40 in the X direction and the Y direction simultaneously. but,
The method of detecting the X and Y directions simultaneously is less accurate.
Further, the air cylinder 52 and the like are controlled using a known control circuit. Furthermore, although this embodiment has been described with respect to the case where the molds are arranged horizontally, it goes without saying that the present invention can also be applied to cases where the molds are arranged vertically. In this case, the suction plate 44 and the frame member 46 will move in the horizontal direction.

Here, as the illustrated sheet 32, a sheet made of thermosetting resin or a transfer film is used.
As the thermosetting resin, in addition to phenolic resin and urea resin, a rubber resin or a primix material obtained by impregnating glass fiber with a thermosetting resin may be used.

Many of these thermosetting resins are heated in a mold to around 200°C to cause a curing reaction and solidify. Therefore, if a pattern is to be applied to these surfaces, the top sheet must also be printed with thermosetting ink on a sheet that is the same type or compatible with the injection resin.

In addition, when painting thermosetting resin using the transfer method, the mold temperature is 150°C to 250°C, so the carrier can withstand this temperature and has good moldability for molded products with drawing. I need it. Possible carriers include glass fiber, nonwoven fabric, or paper impregnated with phenol or urea resin, but these are often hard and brittle, so
Good for flat or shallowly drawn items, but not suitable for deep drawn molded items. Furthermore, since rubber-based resins can also be cured by sulfurization, injection molding for rubber curing is also possible using these resins.

On the other hand, as a carrier film for the transfer method, an engineered plastic film can be cited as one that can withstand the temperature and injection pressure of the mold. For example, heat-resistant films such as polyimide, polysulfone polyarylate, polyether sulfone, and polyethylene coatel ketone are coated with thermosetting ink.For example, epoxy binder with 15% amine curing agent, etc.
Butyral-based ink, cellulose acetate melamine ink, etc. can be used. Although these do not completely harden at room temperature, they harden and become integrated within the mold during injection molding (180°C). That is, the carrier film is preformed in a mold, the thermosetting resin is injected, and then cured in the mold. As a result, the thermosetting resin and thermosetting ink are integrated and cured. Thereafter, the molded product is taken out and the carrier film is wound up.

Next, a specific example will be given.

Specific Example First, a phenol resin (Phenol G grade, manufactured by Sumitomo Chemical Co., Ltd.) is used as a thermosetting resin, and a polysulfone film 30μ (Toray Trethrone) is used as a transfer film. Then, a transfer pattern is printed on the transfer film, and then the suction plate is heated to 210°C.
After heating to 700 ℃, move into the injection mold and vacuum
Vacuum and air pressure preforming was performed at mmHg and air pressure of 2Kg/cm ² . Thereafter, the phenolic resin was injected into a mold at 90°C to 100°C, and cured at a mold temperature of 180°C for 20 seconds to transfer the ink to the surface of the molded product.The molded product was then taken out to form a finished product.

As is clear from the above explanation, according to the method of the present invention, it is possible to automatically and accurately match the pattern of the painted sheet to the molding surface of the female mold, so that the painted sheet can be attached or attached to the molded product without misalignment. You can obtain a finished transferred product. In addition, since painting can be done at the same time as injection molding, production can be extremely efficient and many other effects can be achieved. Furthermore, the painted sheet has a pattern made of thermosetting ink, and since the thermosetting resin is injected and heated into the cavity between the female mold and the male mold, the thermosetting resin and thermosetting resin are heated in the cavity. The adhesive ink can be integrated and cured. Therefore, a molded product with a clear pattern can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a decorated molded product, FIG. 2 is a longitudinal cross-sectional view of an apparatus for carrying out the present invention, FIG. 3 is a plan view of a decorated sheet, and FIG. 4 is a diagram of a ready state for preforming of a decorated sheet. FIG. 5 is a diagram of the inside of the female mold after completion of preforming, and FIG. 6 is a longitudinal sectional view of the female mold and male mold during injection molding. 1...Painted molded product, 16...Male mold, 18...Female mold, 3
2...Pictured sheet, 40...Positioning mark, 42...
Rail, 44... Adsorption plate, 46... Frame member, 52... Cylinder, 54... Detector.

Claims (1)

[Claims] 1. A device held between an unwinding roll and a winding roll,
A decorative sheet having at least a pattern made of thermosetting ink is movably faced between a female mold having a molding surface and a decorative mold equipped with an injection device, and a male mold is placed on one of the front and back sides of the decorative sheet. A suction plate having a ventilation hole is arranged at a distance from the patterned sheet, and a frame moves with the suction plate by sandwiching the decorated sheet with the suction plate at a distance from the decorated sheet on the other side of the front side or the back side of the decorated sheet. The suction plate and the frame member are moved to the proper position relative to the picture on the pictured sheet, and then the pictured sheet is held between the suction plate and the frame member, and then the pictured sheet is held in place. Move the suction plate and frame member between the female mold and the male mold by one pitch of the pattern so that the pattern on the painted sheet faces the correct position on the molding surface of the female mold, and then align the female mold and the male mold. A thermosetting resin characterized in that the thermosetting resin is injected into a cavity between a female mold and a male mold by a male injection device, and the thermosetting resin is heated and molded. Cosmetic method for simultaneous injection molding. 2. The thermosetting resin injection molding and makeup method as claimed in claim 1, wherein the suction plate or the frame member is moved in the direction of clamping the painted sheet by a servo motor. 3. Claims 1 or 2, characterized in that the movement of the suction plate and frame member from the clamping position of the painted sheet to the arrangement position of the female mold and male mold is performed along a rail. The thermosetting resin injection molding and simultaneous makeup method according to any one of the above.