JP2002166700A - Decorating method for three-dimensional shape made of large-sized plastic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative method for performing a thermal transfer, in which a plane thermal transfer foil is favorably adhered to a molding having a comparatively higher stand. SOLUTION: The thermal transfer foil 7 is partially and thermally elongated with a flat heater 17 installed on the side of a bearing jig 5. At the same time, by fixing a shaping cutter 19 to the side of a forming rubber mold 3, a cutting mechanism for cutting off the thermal transfer foil 7 just before the arrival of the forming rubber mold at a downward end is attached, resulting in realizing the favorable adhesion of the thermal transfer foil to a molding 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for decorating a plastics molded product, and more particularly, to a method for covering a surface of a large plastics molded product having a three-dimensional shape with a heat transfer foil and clamping the periphery thereof. The present invention relates to a thermal transfer technique for decorating a molded rubber mold by bringing a foil into a molded article shape by vacuum degassing and then decorating the mold, that is, a so-called three-dimensional hot stamp decorating technique.

[0001]

2. Description of the Related Art As a method of decorating the surface of a large plastics molded product (hereinafter, referred to as a molded product), a thermal transfer foil is put on the molded product, and the periphery of the thermal transfer foil is covered with a foil holding plate (hereinafter, referred to as a foil clamp). After pressing, the thermal transfer foil is attached to the molded product by vacuum suction, and then the shape of the molded product is the same as that of the molded product. There is a method of transferring and decorating a picture on the surface of a molded article. This method is called three-dimensional hot stamping. Hereinafter, this technique will be described in detail using specific examples.

[0002] First, a molded article as shown in FIG. The size of this molded product is 900m long
m, width 300 mm, height 50 mm, wall height 25 mm.
On the other hand, FIGS. 2 and 3 show the appearance and cross-sectional views of a molded rubber mold for hot stamping. The rod-shaped heater 9 is inserted into this, and attached to a stamp device having an up-down mechanism as shown in FIG. The stamping apparatus has a slide table 4 on its inner surface, a receiving jig 5 for fixing an aluminum product manufactured according to the shape of a molded product.
(Hereinafter, referred to as a receiving jig).

[0003] Regarding the above-described mold and receiving jig and apparatus, first, the molded article 6 is transferred to the receiving jig 5 as shown in FIG.
On top. At this time, the thermal transfer foil 7 is set on the space where the slide table is to be inserted for one time by the foil chuck. Next, the slide table is moved to the lower part of the molding rubber mold to the state shown in FIG. 5, and the foil clamp 8 is lowered to fix the thermal transfer foil 7. Then, the roll-side thermal transfer foil 7 is cut by the foil cutting cutter. Next, the thermal transfer foil 7 is brought into close contact with the molded product 6 by removing the air in the room 10 containing the receiving jig 5 and the molded product 6 using a vacuum pump. After the thermal transfer foil 7 is sufficiently adhered, the molding rubber mold 3 is lowered as shown in FIG. 6 to apply heat and pressure to transfer the design to the molded product 6. Thereafter, the molding rubber mold 3 is raised as shown in FIG. 7, and then, as shown in FIG.
Then, after the thermal transfer foil 7 is peeled off from the surface of the molded article 6, the decorated molded article 6 is taken out. Of course, peeling of the thermal transfer foil 7 may be performed after the molded article 6 is received from the jig 5. If foil burrs remain on the grid portion after the thermal transfer foil 7 has been peeled off, rub the grid portion with a sponge or the like, and then finish with a vacuum cleaner. In addition, the heat transfer foil 7 is continuously supplied using a foil roll,
A method of peeling the thermal transfer foil 7 with a foil peeling bar after transfer has already been implemented as a mass production method.

[0004]

There is a limit to the shape of a molded product that can be mass-produced and decorated by performing three-dimensional hot stamping. This is because the surface of a large plastic molded product having a three-dimensional shape is decorated with a hot stamp using a thermal transfer foil by the above-described method. Since it is necessary to closely adhere to the three-dimensionally formed product, the side wall cannot be made too high. As shown in FIG. 30 at the time of vacuum suction, when the molded rubber mold is lowered in a state in which the thermal transfer foil does not adhere to the side end, the molded rubber mold is moved to the lower end, that is, the outer periphery of the molded product before reaching the molded product surface. I touched the thermal transfer foil,
The thermal transfer foil is torn (hereinafter referred to as foil crack). As a result, the vacuum is broken and the thermal transfer foil is no longer in close contact with the molded product, and uniform decoration cannot be performed. Specifically, large poor adhesion and countless wrinkles occur. Because of the state described above, there is a limit to the shapes that can be decorated with the three-dimensional hot stamp by the conventional method. Since this is determined by the combination of the shape elements, it is difficult to define it differently. However, it can be estimated by a combination of the following four factors. That is, (1) the height h _{1 of} the side wall shape, (2) the distance h ₂ from the product top to the side end, (3) the angle α between the side wall surface and the horizontal plane, and (4) the intersection R of the side wall surface and the horizontal plane. Size, etc. Further, the side shape may gradually change in shape, so that it may not be possible to judge the side shape solely by a numeral. For example,
An example of a shape in which no problem has occurred among the shapes subjected to mass production will be described in detail with reference to the drawings. That is, the side rising portion has a relatively gentle shape as shown in FIGS. 9 to 12, and the angle α is an obtuse angle.

However, due to the change in the design of the air conditioner grill, as shown in FIGS. 13 to 16 and FIGS. 17 to 20, the distance h ₂ from the product top to the side end of the molded product is increased, and the side wall shape depth is increased. h ₁ is a deep shape of the product began to appear. And like this,
There were many customers who wanted to decorate the air conditioner grill with a deeper shape using this method.

[0009] When the decoration is performed by the conventional method, FIGS.
With the shape of 2, the heat transfer foil can be brought into close contact with the side end of the molded product during vacuum suction. By lowering the molding rubber mold, the pattern can be uniformly transferred to the molded product.

However, if the shape is as shown in FIG. 13 to FIG. 16, it becomes difficult for the heat transfer foil to reach the side end of the molded product at the time of vacuum suction, and as described above, foil cracking occurs and three-dimensional hot stamp decoration is impossible. Becomes

A method has been conceived in which a thermal transfer foil is positioned directly under a molding rubber mold for a long time, heating is sufficiently performed, and the thermal transfer foil is more easily stretched during vacuum suction. However, when the thermal transfer foil comes into contact with the molded product after the clamp plate is lowered, it is instantaneously cooled. In general, the heat distortion temperature of the molded product (HIPS, ABS) is 100 ° C. or less, and the heat distortion temperature of the foil (PET film) is 1 ° C.
Since the temperature is lower than 20 ° C., the thermal transfer foil and the molded article cannot be heated together during vacuum suction. From the above, at the time of vacuum suction,
It was difficult to heat and stretch only the PET film using a rubber mold.

[0009] Even in the molded product having the shape shown in Figs.
Before the molding rubber mold is lowered and the foil pattern is thermally transferred, that is, before the molding rubber mold reaches the descending end,
Contacting the stretched thermal transfer foil and breaking the foil causes vacuum breakage, making it impossible to transfer the pattern itself.
Poor adhesion and wrinkling as shown in FIG. In addition, even if the foil tearing strength is sufficient and vacuum breakage due to foil cracking does not occur luckily, poor adhesion at the ends as shown in FIG. 22 and ring-shaped scratches as shown in FIG. As a result, no good product was obtained. The ring-shaped scratch is a trace of shrinkage of the foil, which remains on the molded product due to the warmed foil being re-cooled and shrinked after the rise of the molding rubber mold.

As described above, the two-dimensional thermal transfer foil is
There is a limit in bringing the molded product into close contact with a three-dimensional shaped product, and mass production is impossible unless the shape is limited.

[0011]

Means for Solving the Problems The present inventor has taken the above-mentioned circumstances and technical problems into consideration, and as a result of earnest research, has found that the surface of a large plastic molded article having a deeper three-dimensional shape can be obtained. They have invented a method of decorating using a thermal transfer foil and a molded rubber mold. The configuration and outline of the procedure of the present invention will be described below in order.

First, the first aspect of the present invention will be described. In correspondence with the shapes shown in FIGS. 13 to 16, a sheet heater 17 is provided beside the receiving jig on the side surface of the molded product 6 as shown in FIGS.
By heating the thermal transfer foil with this planar heater 17, the thermal transfer foil is partially heated and stretched during vacuum suction,
Adhere to molded product. The molding rubber mold may have a conventional configuration.

Next, a second aspect of the present invention will be described. Although this corresponds to the shapes shown in FIGS. 17 to 20, the thermal transfer foil cannot reach the side end of the molded product only with the first invention. As shown in FIG. 26, a shape cutter is fixed to the side surface of the molded rubber mold, and a mechanism for cutting the thermal transfer foil is attached immediately before the molded rubber mold reaches the lower end. In addition, when the molding rubber at the end of the molded article and the foil surface are not slippery, a lubricant such as silicon grease is applied.

Since the present invention is configured as described above, the following effects are confirmed in hot stamp decoration of a plastics molded product having a deep three-dimensional curved surface. In the first invention, the heat transfer foil is heated by heating the heat transfer foil in the vicinity of the portion to be in close contact with the molded article by the sheet heater, and the heat transfer foil is closely attached to the deeper side surface in combination with the vacuum suction. It is possible to make it. In the second invention, the thermal transfer foil that has been stretched to the limit by vacuum suction can be cut just before the molding rubber mold reaches the lower end,
It becomes possible. After the cutting, the tension of the thermal transfer foil becomes zero, and the molded rubber mold having a deep shape as shown in FIG. 26 is covered, and the thermal transfer foil is stretched to its limit. It will not be done. In the third invention,
Slip between the surface of the molded rubber and the surface of the thermal transfer foil is improved, and more reliable thermal transfer can be performed. More specifically, the adhesiveness at the end is more improved than when no coating is performed.

[0015]

As described above, the following main effects can be obtained. According to the first aspect of the present invention, it is possible to selectively heat and elongate only a portion in the vicinity where the thermal transfer foil is to be stretched and brought into close contact with the molded article by heating with the sheet heater. As a result, the thermal transfer foil is brought into close contact with the end of the molded product, and it is possible to prevent collision between the molded rubber mold and the foil R portion when the molded rubber mold descends, thereby performing favorable decoration. In the second invention, the tension of the foil that has been elongated by vacuum suction can be eliminated by cutting the foil immediately before thermal transfer using a shape cutter for the molded rubber mold. As a result, the pattern of the thermal transfer foil is transferred to the end of the molded product, and the defects shown in FIG. 22 do not occur. Further, even if the molded rubber mold rises after the thermal transfer, the occurrence of ring-shaped scratches as shown in FIG. 23 caused by the re-shrinkage of the thermal transfer foil is not observed. Usually, a molded article having a shape adapted to the second invention also uses the first invention. Therefore, the foil is cut immediately before the transfer while keeping the thermal transfer foil in close contact with the molded product, so that the decorated molded product can be favorably decorated without generation of wrinkles.

In the third invention, more favorable three-dimensional decoration can be performed by using it in combination with the first invention and the second invention. As described above, by applying the first invention, the second invention, and the third invention to the three-dimensional hot stamp decorating technique, it is possible to obtain a deep object three-dimensional shape that has been considered difficult to decorate. It is now possible to decorate a molded product with a hot stamp. The molded product having the shape as shown in FIGS. 13 to 20 could be mass-produced by using the method of the present invention.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The dimensional shape decoration method will be specifically described with reference to the drawings. 9 to 12 and FIGS. 13 to 16
And the side shapes of the molded articles shown in FIGS. 17 to 20, h ₁ ... Total side height, h ₂ .
... the side angles are shown in a table in FIG. First, an embodiment of only the first invention will be described. The molded product is an air conditioner grill having the shape shown in FIG. The size of this molded product is 800 mm in length, 200 mm in width, 44 mm in height, and 23 mm in wall height.

The state during suction of the thermal transfer foil will be described with reference to the drawings. The thermal transfer foil is in a state as shown in FIG. 28 before vacuum suction. Next, a state as shown in FIG. 29 is obtained by vacuum suction according to the conventional method, and the thermal transfer foil 7 does not reach the end of the molded product 6. As shown in FIG.
In a state where a planar heater 17 (hereinafter, referred to as a side heater) is installed, when vacuum suction is performed, the thermal transfer foil 7 is partially heated and stretched, thereby forming the molded product 6.
The thermal transfer foil 7 can be brought into close contact with the end.

In the state described above, when the molding rubber mold 2 is lowered and the thermal transfer of the picture is performed, in the conventional method, as shown in FIG. End hits the thermal transfer foil 7, the thermal transfer foil 7 is broken, and a vacuum break occurs. In addition, since the molding rubber 3 is heated to 180 ° C., the collision with the free part of the thermal transfer foil 7 made of polyethylene terephthalate film instantaneously breaks the thermal transfer foil 7.

On the other hand, in the state of FIG. 32 where the present invention is used, since the thermal transfer foil 7 is sufficiently lowered to the lower end of the molded product, vacuum breakage does not occur even if the molded rubber mold 2 is lowered. And good pattern transfer can be performed. Note that a silicon rubber heater was used as the sheet heater 17.

In addition, if the friction coefficient between the surface of the molding rubber 3 and the thermal transfer foil 7 is reduced by applying silicon grease or the like to the surface of the molding rubber 3 in a strict portion of the shape, even better pattern transfer is performed. be able to. As described above, when the wood grain pattern decoration was performed on the air conditioner grill having the shape shown in FIGS. 13 to 16 by the method using the first invention in the present invention, good results were obtained.

Next, an embodiment in which the first invention and the second invention are used in combination will be described. The molded product is an air conditioner grill having the shape shown in FIGS. The size of this molded product is 800 mm in length, 270 mm in width, and 115 mm in height.
mm, wall height 30 mm. As shown in FIG. 36, when the molded product side angle α is extremely small, the thermal transfer foil 7 is partially stretched using the planar heater 17 and the molded product 6
As described above, even if it is attached to the end, a ring-shaped flaw as shown in FIG. 23 remains due to shrinkage of the thermal transfer foil 7 after thermal transfer decoration.

FIG. 33 is a sectional view of the center of a molded product as an embodiment of the second invention. The thermal transfer foil 7 is in close contact with the molded product 6 by vacuum suction. The molding rubber mold 3 is lowered, and just before the molding rubber 3 reaches the surface of the molded product 6, the cutting edge of the shape cutter 19 touches the thermal transfer foil 7 and cuts. Immediately thereafter, the molded rubber 2 reaches the surface of the molded product 6, and the pattern of the thermal transfer foil 7 is transferred. More specifically, the thermal transfer foil 7 is tightly adhered to the molded product 6 without cutting before cutting, and the pattern is transferred to the molded product by the molding rubber 2 immediately before cutting before wrinkling occurs. Therefore, no wrinkles are seen in the decorated molded article 6. Further, when the molding rubber mold 2 rises, since the thermal transfer foil 7 is cut as shown in FIG. 35, a ring-shaped scratch due to the contraction of the thermally transferred foil that has been forcibly extended occurs on the side surface of the molded product. Did not. In this method, since the thermal transfer foil is cut, the winding method cannot be used.

As described above, the air conditioner grill having the shape shown in FIGS. 13 to 16 is decorated with a wood grain pattern by the method using the first invention and the second invention in the present invention. Obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of a molded article capable of performing effective surface decoration by performing a conventional three-dimensional hot stamping.

FIG. 2 is a perspective view of a molded rubber mold created for performing a conventional three-dimensional hot stamping.

FIG. 3 is a cross-sectional view of a molded rubber mold created for performing a conventional three-dimensional hot stamping.

FIG. 4 is a view showing one state when decorating a large plastics molded product using a molded rubber mold by a conventional three-dimensional hot stamping method.

FIG. 5 is a view showing another state when decorating a large plastics molded product using a molded rubber mold by a conventional three-dimensional hot stamping method.

FIG. 6 is a view showing still another state when decorating a large plastics molded product using a molded rubber mold by a conventional three-dimensional hot stamping method.

FIG. 7 is a view showing still another state when decorating a large-sized plastics molded product using a molded rubber mold by a conventional three-dimensional hot stamping method.

FIG. 8 is a view showing one state when decorating a large plastics molded product using a molded rubber mold by a conventional three-dimensional hot stamping method.

FIG. 9 is a perspective view showing a molded product mass-produced by a conventional three-dimensional hot stamping method.

FIG. 10 is a plan view showing a part of the molded article.

FIG. 11 is a side view showing the molded article.

FIG. 12 is a front view showing a part of the molded product.

FIG. 13: Using the first invention shown in claim 1 of the present invention,
It is a perspective view showing the molded product which performed mass production.

FIG. 14 is a plan view showing a part of the molded article.

FIG. 15 is a side view showing the molded article.

FIG. 16 is a front view showing a part of the molded product.

FIG. 17 is a perspective view showing a molded product mass-produced by the three-dimensional hot stamping method by using the first invention shown in claim 1 of the present invention and the second invention shown in claim 2 of the present invention together; It is.

FIG. 18 is a plan view showing a part of the molded article.

FIG. 19 is a side view showing the molded article.

FIG. 20 is a front view showing a part of the molded article.

FIG. 21 is a side view showing a defect that occurs when three-dimensional hot stamping is performed on the molded product shown in FIGS. 17 to 20 without using the second invention according to the second aspect of the present invention.

FIG. 22 is a side view showing a defect that occurs when three-dimensional hot stamping is performed on the molded product shown in FIGS. 17 to 20 without using the second invention according to the second aspect of the present invention.

23. The molded article shown in FIG. 7 according to claim 2 of the present invention.
FIG. 7 is a side view showing a defect that occurs when performing three-dimensional hot stamping without using the second invention shown in FIG.

FIG. 24 is a plan view showing a part of a decorating apparatus for executing the decorating method according to the first embodiment of the present invention.

FIG. 25 is a front view of FIG. 24;

FIG. 26 is a front view of an embodiment of the second invention shown in claim 2 of the present invention.

FIG. 27 is a side view showing a molded rubber mold according to the second embodiment of the present invention.

FIG. 28 is a front view of a state before suction of the thermal transfer foil.

FIG. 29 is a front view of a state during vacuum suction according to a conventional method.

FIG. 30 is a front view showing a state where a molding rubber mold is lowered during vacuum suction in FIG. 29;

FIG. 31 is a front view of a state during vacuum suction when the first invention described in claim 1 of the present invention is carried out.

FIG. 32 is a front view showing a state where a molding rubber mold is lowered during vacuum suction in FIG. 30;

FIG. 33 is a sectional view showing a state during vacuum suction in the embodiment of the second invention shown in claim 2 of the present invention.

FIG. 34 is a cross-sectional view showing a state immediately before thermal transfer decoration in FIG.

FIG. 35 is a cross-sectional view showing a state after completion of thermal transfer decoration in FIG. 33 and after a molding rubber mold is raised.

FIG. 36 is a table showing side shapes of the molded products shown in FIGS. 9 to 20;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Lattice 2 ... Molded rubber 3 ... Molded rubber mold 4 ... Slide table 5 ... Receiving jig 6 ... Molded product 7 ... Thermal transfer foil 8 ... Foil clamp 9 ... Bar-shaped heater 10 ... Vacuum degassing part 11 ... Side part 12 ... Lattice part 13 ... Poor adhesion part 14 ... Wrinkle 15 ... Part where fine wrinkles occur 16: Ring-shaped scratches generated at the time of thermal transfer foil re-shrinkage 17: Planar heater 18: Planar heater receiver 19: Shape cutter 20: Bolt for fixing shape cutter 21: Spacer

Claims (3)

[Claims] 1. A large-sized plastics molded article having a three-dimensional shape is covered with a heat transfer foil, and the periphery thereof is clamped.
After attaching the foil to the molded product shape by vacuum degassing, up and down the molding rubber mold and decorate it, in the technology of decorating, place a sheet heater around the receiving jig and remove the heat transfer foil A method that enables decoration of deeper shaped articles by heating and extending. 2. A large-sized plastics molded article having a three-dimensional shape is covered with a thermal transfer foil, and the periphery thereof is clamped.
After attaching the foil to the molded product shape by vacuum degassing and then decorating the molded rubber mold up and down, a cutter is attached around or part of the molded rubber mold, and the molded rubber mold is A method in which the thermal transfer foil is cut just before reaching the descending end, thereby removing the tension of the thermal transfer foil and enabling decoration of a deeper shaped molded article. 3. A large-sized plastics molded article having a three-dimensional shape is covered with a thermal transfer foil, and its periphery is clamped.
After applying the foil to the molded product shape by vacuum degassing, the molding rubber mold is raised and lowered, and in the decorating technology, when decorating a molded product with a deep vertical shape, the molding rubber end A method in which a lubricant is applied to the vicinity of the portion to improve the slippage between the surface of the molded rubber and the surface of the thermal transfer foil, thereby performing more reliable thermal transfer.