KR20010005456A - method of manufacturing synthetic resin wares decorated by in-moulding - Google Patents

Abstract

PURPOSE: A method for manufacturing synthetic resins decorated by in-moulding is provided to decorate the surface of synthetic resins products forming corners or having three-dimensional surfaces with continuous decoration patterns and permanently maintain the decoration patterns. CONSTITUTION: A method for manufacturing synthetic resins decorated by in-moulding includes the steps of printing a reverse side of a transparent film(1) with a predetermined decoration pattern, compressively forming the printed film in a predetermined shape, cutting the compressively formed film, installing the cut film at a metal mold cavity, and injecting the melted synthetic resins on the reverse side of the film.

Description

Method of manufacturing synthetic resin wares decorated by in-moulding

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a synthetic resin product on which a surface of a mobile phone cover, a control panel, or an automobile interior is decorated, and specifically, a predetermined decorative pattern on a general transparent film or a transparent film having a hair line formed thereon Printing the back surface; Compressing and molding the printed film into a predetermined shape; Cutting the compressed and molded film; Installing the cut film in a mold; It relates to a method for producing a synthetic resin product decorated by in-moulding comprising the step of injecting the molten synthetic resin on the back surface of the film.

Conventionally, in order to decorate the surface of a synthetic resin product by in-moulding, a flat polypropylene film having a decorative pattern printed thereon is attached to the mold cavity surface by electrostatics, and then molten polypropylene is injected and molded integrally. There was a method of decorating the plane of, but it was difficult to decorate a continuous decorative pattern on the surface of the angled synthetic resin products and also difficult to decorate with a hairline.

As shown in FIG. 8, the conventional water-repellent printing method for solving the above problem is a floating step in which the back surface on which the printed pattern 1 is printed is floated on water 29 and the printed film ( There was also a printing method comprising a transfer step of pressing and transferring 1), a removing step of removing the film 1, and a coating step of coating the object 31 with a predetermined material, but the transfer film 1 and the object ( There is a problem in that the defective pattern of the decorative pattern is high, the decorative pattern is not precise, and the coating is cumbersome by post-printing due to the misalignment of 31).

The present invention has been made to solve the above problems, an object of the present invention is to form a continuous, continuous surface of the synthetic resin products, such as the cover of the mobile phone having a three-dimensional shape, the control panel, the interior of the car, etc. It is to provide a method of manufacturing a synthetic resin product is decorated with a decorative pattern, if necessary a hairline formed on the surface.

Another object of the present invention is a method of manufacturing a synthetic resin product that is precisely printed in a continuous decorative pattern on the surface of the synthetic resin product, such as a cover, a control panel, a car interior, etc., each having a three-dimensional solid surface. To provide.

Another object of the present invention is to print the surface of the synthetic resin products, such as the cover, the control panel, the interior of the mobile phone having a three-dimensional solid surface or three-dimensional shape in a continuous decorative pattern, and does not require a separate coating process It is to provide a method for producing a synthetic resin product.

It is another object of the present invention to provide a method for manufacturing a synthetic resin product having improved waterproof function by eliminating assembly gaps of a body and an operation button of a synthetic resin product such as a cover, a control panel, and an interior of a mobile phone.

1 is a view showing a process of screen printing a predetermined decorative pattern on a transparent film,

Figure 2a, b, c, d is a view showing a process in which the printed film is compressed and molded,

3 is a perspective view of a compressed and molded film according to Example 1,

4 is a perspective view of an injection-molded synthetic resin product according to Example 1,

5 is a view showing a process of processing a hairline on a transparent film according to Example 2,

6 is a perspective view of a compressed and molded film according to Example 2,

7 is a perspective view of an injection-molded synthetic resin product according to Example 2. FIG.

8 is a view showing a decoration method by a conventional water-repellent method;

9 is a view showing a laminated film according to Example 3 of the present invention;

10 is a perspective view of a compressed and molded film according to Example 3 of the present invention,

11 is a perspective view of an injection-molded synthetic resin product according to Example 3 of the present invention.

<Explanation of symbols for main parts of drawing>

1 film, 3 surface,

5 ... back side, 6 ... brush,

7.film roll, 9 ... upper,

11 ... lower, 13 ... mother tool,

15 ... inlet, 17 ... outlet,

19 ... shielding, 21 ... outer line,

23 mobile phone cover, 25 print layer,

27 injection molding, 29 water,

31 objects, 32 thin films,

33 display unit, 34 button unit,

35.Songhwabu, 36.Halls,

37 ... Hydraulic department.

In order to achieve the above object, the present invention is to print the surface of the synthetic resin product by the in-molding (in-molding) method, unlike the conventional involves the step of compression and molding a transparent film.

Hereinafter, with reference to the accompanying drawings, a method of manufacturing a mobile phone cover 23, the surface of which is decorated with a decorative pattern according to a preferred embodiment of the present invention will be described in detail.

1 shows that the decorative pattern is printed on the back surface 5 by the screen printing method on the transparent film 1. The transparent film 1 is preferably polycarbonate (polycabonate) and the thickness is 100 ~ 500㎛. The decorative pattern is repeatedly printed many times in multiple colors such as wood grain, flora and fauna, various logos, and the print layer 25 is formed. At this time, the decorative pattern is printed on the back surface 5, the unprinted surface 3 becomes the surface of the finished synthetic resin product, and the transparent film 1 itself becomes a coating film, and a separate coating process is omitted.

2A, 2B, 2C and 2D show an air pressure forming apparatus for molding the printed film 1 according to a predetermined shape. The air pressure forming apparatus is composed of an upper mold 9 that is largely fixed and a lower mold 11 that moves up and down by a mother tool 13. At the center of the upper die 9, an inlet 15 through which 0 to 350 bar of compressed air is blown is provided at the center, and a force for forming the printed film 1 is provided, and at the edge of the upper die 9, a shielding part ( 19 is installed and connected to the shielding portion 19 of the mother tool 13, thereby preventing the leakage of compressed air. In addition, an outlet 17 is installed at the center of the lower mold 11 so that the air located between the printed film 1 and the lower mold 11 while the printed film 1 is being molded is connected to the outlet 17. After compression and molding, the compressed air is blown into the mold through the outlet 17, and the film 1 is released. A shielding portion 19 is installed at the edge of the mother tool 13 and connected to the shielding portion 19 of the upper mold 9 to prevent leakage of compressed air, and the lower mold 11 is attached to the mother tool 13. It is mounted and transported up and down.

Figures 2a, 2b, 2c, 2d sequentially shows the operation of the air compression molding apparatus. The lower die 11 mounted on the mother tool 13 is normally in a standby state under the work surface. The printed film 1 is mounted on a pallet (not shown) two by two, transferred to a heating device (not shown), and heated. At this time, the unprinted surface 3 of the film 1 is mounted on the pallet so as to be upward, and preferably the heating temperature is 280 ° C to 300 ° C. As shown in FIG. 2A, the heated film 1 is transferred to the lower part of the upper mold 9, at which time the lower mold 11 mounted on the mother tool 13 starts to rise. As shown in FIG. 2B, the upper die 9 and the shielding portion 19 of the mother tool 13 are coupled, and the heated film 1 is supported by the shielding portion 19. As shown in FIG. 2C, compressed air is blown from the inlet 15 of the upper mold 9, and the air located between the film 1 and the lower mold 11 is discharged from the outlet 17 of the lower mold 11, The printed film 1 is compressed and molded into the shape of the mobile phone cover 23. As shown in FIG. 2D, after the lower mold 11 is slightly lowered, compressed air is blown to the lower surface of the film 1 at the outlet 17 of the lower mold 11 so that the compressed and molded film 1 is lowered ( 11) is released.

3 shows a compressed / molded film 1 according to Example 1. FIG. The compressed and molded film 1 is cut to fit the outer line 21 of the mobile phone cover 23 (see Fig. 4), and the assembly parts such as the button part and the display part of the mobile phone are cut.

In FIG. 4, the cut film 1 according to Example 1 is mounted in an injection molding mold cavity (not shown), and the cellular phone cover 23 in which molten synthetic resin is injected onto the back surface 5 of the film 1 is manufactured. ) Is shown. The mobile phone cover 23 is positioned in the order of the transparent film layer 1, which serves as a coating film, the printed layer 25 on which a decorative pattern is printed, and a general injection molding 27, to protect the printed decorative pattern. The coating process was omitted, and the decorative pattern is continuously printed on the side surface of the mobile phone cover 23 and the three-dimensional solid surface.

Hereinafter, a method of manufacturing a mobile phone cover 23, the surface of which is decorated with a hairline, according to a second embodiment of the present invention will be described in detail with reference to the accompanying drawings.

A step of processing the hairline on the surface 3 of the film 1 is added first, and subsequent processing steps are the same as in Example 1.

In Fig. 5 there is shown an apparatus in which the hairline is processed on the surface 3 of the film 1 according to the invention. While winding from the film roll 7 on the other hand to the film roll 7 on the other side, a brush 6 is provided in the center of the roll 7 so that the surface 3 of the transparent synthetic resin film 1 is brushed. It is scratched by (6) and a hairline is formed. A sand roll may be installed instead of the brush 6.

The decorative pattern is printed by the screen printing method on the film back surface 5 which is the opposite surface to the film surface 3 on which the hairline is formed.

6 shows a compressed and molded film 1 according to Example 2. FIG. The compressed and molded film 1 is cut to fit the outer line 21 of the mobile phone cover 23 (see Fig. 5), and the assembly parts such as the button part and the display part of the mobile phone are cut.

FIG. 7 shows a cell phone cover 23 in which a cut film 1 according to Example 2 is mounted in an injection molding mold cavity (not shown), whereby molten synthetic resin is injected onto the back side of a printed film. have. The mobile phone cover 23 has a surface 3 on which an external aesthetic hairline is formed, a film layer 1 serving as a coating film, a printed layer 25 on which a decorative pattern is printed, and a general injection molding 27. In order to protect the printed decorative pattern, the conventional coating process is omitted, and the decorative pattern is continuously printed on the side surface of the mobile phone cover 23 and the three-dimensional solid surface, and is naturally decorated with a hairline.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment 3 of the present invention will be described in detail.

In the third embodiment, the main difference between the first and second embodiments is that in the cutting step, the button part 34 and the display part 33 of the mobile phone are not cut and only the outer line 21 is cut or the back surface ( (5) After the printing step, the hole 36 is formed in the portion of the film 1 corresponding to the transfer part 35 and the hydration part 37 and the thin film 32 is formed on the lower portion of the printing layer 25. The step of stacking is added. This different configuration will be mainly described.

As shown in Fig. 9, as described above in Examples 1 and 2, a predetermined decorative pattern is screen printed on the transparent film 1 to form a printing layer 25 on the back surface of the film 1. For example, a hole 36 is formed at a portion that needs to transmit and receive sound waves to the outside, such as the transmitter 35 and the receiver 37 of the mobile phone cover, and a thin film 32 below the printed layer 25. This is laminated. Preferably this thin film 32 has a thickness of 50 μm and is made of polycarbonate.

After the thin films 32 are laminated in this manner, the laminated films 1 after printing as in Examples 1 and 2 are compressed and molded.

In the cutting step, as shown in FIGS. 10 and 11, only the outer line 21 of the mobile phone cover 23 is cut, and the button 34 and the display 33 of the mobile phone are not cut, so that the cover of the mobile phone is cut. There is no assembly gap between the 23 and the button 34, the waterproof function of the mobile phone cover 23 is improved. And the transmitter 35 and the receiver 37 are improved by the thin film 32 without disturbing the progress of the sound wave by the hole 36 previously punched.

Next, the film 1 cut | disconnected like Example 1, 2 is mounted in the injection mold metal cavity (not shown), and molten synthetic resin is inject | emitted upward of the back surface 5 of the film 1. In this case, since the print layer 25 and the thin film 32 are not formed in the display unit 33, the synthetic resin is immediately injected, and the injection molding 27 is positioned. The injection molded article 27 is made of transparent synthetic resin so that the function of the display unit 33 is not deteriorated.

In the above, the mobile phone cover 23 decorated by the in-mold has been described in detail as Examples 1, 2, and 3, but the manufacturing method of the synthetic resin product, which is decorated by the same in-mold, is also used to manufacture synthetic resin products such as control panels and automobile interiors. Can be applied.

The effects on the method of manufacturing a synthetic resin product decorated by the in-molding of the present invention made as described above are as follows.

First, a decorative pattern is easily printed on the surface of various synthetic resin products such as a mobile phone cover, a control panel, and an automobile interior, and if necessary, the decorative pattern can be decorated with a hairline.

Secondly, the surface of various synthetic resin products having an angled portion or a three-dimensional surface of a three-dimensional shape is accurate, and can be easily printed.

Third, after the decorative pattern is printed on the surface of various synthetic resin products, there is an effect that the coating process is usually required.

Fourth, there is an effect of improving the waterproof function by eliminating the assembly gap of the body and the operation button of the synthetic resin products, such as the cover of the mobile phone, the control panel, the car interior.

Claims (4)

A method of producing a synthetic resin product, the surface of which is decorated, the method comprising: printing a back surface (5) with a predetermined decorative pattern on a transparent film (1); Compressing and molding the printed film 1 into a predetermined shape; Cutting the compressed and molded film 1; Installing the cut film (1) in a mold; And a step of injecting the molten synthetic resin onto the back surface (5) of the film (1). The method of producing a synthetic resin product according to claim 1, characterized in that the surface (3) of the transparent film (1) is processed into a hair line. The method according to claim 1 or 2, The synthetic resin product is a mobile phone cover 23, in the cutting step, the button portion 34, the display unit 33 of the mobile phone is not cut, characterized in that only the outer line 21 is cut (in Method of manufacturing synthetic resin products decorated by moulding). The method of claim 3, Immediately after the printing of the back surface 5, a hole 36 is formed in a portion of the film 1 corresponding to the transmitter 35 and the receiver 37; A method of manufacturing a synthetic resin product, which is decorated by in-moulding, characterized in that the step of laminating a thin film (32) below the printing layer (25) is added.