JPS6251408A - Exterior trim part for watch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to an exterior part for a watch.

[Prior art and its problems] Conventionally, decorative paint was applied to the surface of the exterior parts of the exterior parts of watches, such as cases and bands, in order to improve the design. There was a problem that it peeled off easily. Therefore, recently, a printed layer or a vapor deposited layer is transferred onto the surface of the exterior component body using a hot stamping method. However, with this hot stamping method, there are variations in the shrinkage and expansion that occur during molding, so there are problems such as unevenness on the exterior component body and difficulty in accurately transferring the material to the side surfaces of the exterior component body. . Especially since watch bands are elastic.

This has the disadvantage that it deforms when pressure is applied, making accurate transfer impossible.

[Object of the Invention] This invention was made in consideration of the above circumstances, and its purpose is to accurately and satisfactorily apply a decorative layer on the surface of an exterior component body, regardless of the material. It is an object of the present invention to provide an exterior part for a timepiece that can be installed and is preferable in terms of design and appearance.

[Summary of the Invention] In order to achieve the above objects, the present invention places a thermal transfer sheet in a mold for molding an exterior component, injects resin to form an exterior component body, and then The decorative layer of the thermal transfer sheet is transferred to the exterior component body by peeling off the base sheet.

[Embodiment] An embodiment in which the present invention is applied to a wristwatch will be described below with reference to FIGS. 1 to 10.

1 and 2 show a wristwatch case with an integrated band. This watch case l has a metal layer 4 as a decorative layer on the surface of a case body 1a in which a case part 2 and band parts 3, 3 are integrally formed. A transparent resin layer 5 is provided on the surface of the metal layer 4.
6. That is, the case part 2 houses a clock device (not shown) such as a clock module therein, and is made of a hard synthetic resin such as ABS resin, and is provided on both sides by biting into each band part 3.3. connecting part 2
a and 2a are formed in a "U" shape.

The band portion 3.3 is made of synthetic resin such as polyurethane,
One end of each (the left end in FIG. 1) is formed integrally with both ends of the case part 2, surrounding the connecting parts 2a, 2a, and a large number of decorative grooves 3am are formed on the top surface. The metal layer 4 is for making the case body 1a look metallic, and is provided on the surface of the case body 1a, as will be described later. The resin layers 5 and 6 protect the metal layer 4, and the resin layer 5 provided on the case part 2 forms a watch glass and is made of transparent hard synthetic resin such as acrylic. The resin layer 6 provided on 3.3 is made of a transparent soft resin such as polyurethane.

Next, the case of manufacturing the watch case l as described above will be explained with reference to FIGS. 3 to 1O.

As shown in FIG. 3, the metal layer 4 is coated with a thermal transfer sheet 7 in advance.
established in That is, the thermal transfer sheet 7 has a metal layer 4 formed on the lower surface of a base sheet 8 via a release layer 9, and an adhesive layer 10 provided on the lower surface of the metal layer 4. in this case,
The 7Ji material sheet 8 is a synthetic resin film and has a thickness of about 253L. The peeling layer 9 peels off the metal layer 4 from the base sheet 8, and has a thickness of about 51L. The metal R4 is formed into a foil by vapor-depositing the metal, and its thickness is about 20 to 30 JL. moreover,
The adhesive layer 10 is used to adhere the metal layer 4 to the surface of the case body 1a, and its thickness is about a divisor. Therefore, the thermal transfer sheet 7 is extremely thin, with a total thickness of about 50 to 60 mm.

The thermal transfer sheet 7 configured in this manner is placed in a mold 11 for primary molding, as shown in FIGS. 4 and 5.

In this case, the mold 11 consists of an upper mold 11a and a lower mold 11b, and the upper mold 11a has a case part 2 of the case body 1a.
A cavity 12 is provided in the lower mold 11b to form connecting parts 2a on both sides of the case part 2.
, 2a are replaceably provided. When placing the thermal transfer sheet 7 in the mold 11, as shown in FIG. Thermal transfer sheet 7
Place. Then, the upper mold 11a is placed under the lower mold 11b.
When brought into close contact with each other, the thermal transfer sheet 7 becomes as shown in FIG.
It is elongated due to the unevenness of the upper and lower molds 11a and 11b. Thereafter, the upper and lower molds 11a and 11b are clamped and resin is injected, and the injection pressure causes the thermal transfer sheet 7 to be placed in close contact with the inner upper surface of the cavity 12, as shown in FIG. That is, the upper mold 11a is provided with a gage 14, and this gage 14 communicates with an injection path 15 provided in the lower mold 11b, and the ABS is injected into the cavity 12 through the injection path 15. It is designed to inject molding resin such as resin. Therefore, the resin flows from the gate 14 into the injection path 1.
5 into the cavity 12, the case part 2 of the case body 1a is formed as shown in FIG. molded. At this time, the thermal transfer sheet 7 is integrally provided on the upper surface of the case portion 2 by the adhesive layer IO, and the primary molding is completed.

After the primary molding is completed in this manner, the mold 11 is released and the upper mold 11a is separated from the lower mold 11b. Then, the primary molded product (case part 2 and thermal transfer sheet 7)
is fixed to the lower mold ttb and taken out from the upper mold 11a. After this, as shown in FIG. 8, the lower mold 11b
The inner slide core 13.13 is extracted and replaced with another slide core 16.16, and the upper mold 11a is replaced with an upper mold 11c for secondary molding. In this case, the upper mold 11c for secondary molding has a cavity 17.17 formed therein for molding the band portion 3.3, and the thermal transfer sheet 7 is placed on the upper surface of this cavity 17.17.

In this case, the thermal transfer sheet is in close contact with the lower mold 11b, but when a molding resin such as polyurethane is injected from below, the thermal transfer sheet is brought into close contact with the upper mold 11a due to the injection pressure. Resin is injected into the cavity 17.17, and when it solidifies, the band parts 3, 3 are integrally formed on both sides of the case part 2, and the case body 1 is formed as a secondary molded product.
a is formed. After the secondary molded product is molded in this way, the upper and lower molds 11c and llb are opened, and the upper mold 11
The secondary molded product is taken out from inside c, and the base sheet 8 of the thermal transfer sheet 7 is peeled off from this secondary molded product. Then, the metal layer 4 remains on the surface of the case body 1a.

Thereafter, the lower mold 11b is moved to the lower side of the upper mold ttc+ for tertiary molding, as shown in FIG.

The molded product with the base sheet 8 peeled off is placed in the upper mold lid to correspond to the cavity 18 in which the resin layer 5 for the watch glass is molded.
The upper and lower molds 11d, 1 are placed in the cavity 18 of
Clamp 1b. In this state, gate 1 for tertiary forming
When resin is injected into the cavity 18 from 9, the resin is integrally formed on the surface of the metal layer 4 on the case portion 2, and the resin layer 5 as a watch glass is formed as a tertiary molded product.

After that, the upper and lower molds 11d and 11b are released again, and the lower mold 11b is moved to the lower side of the upper mold lie for 4th molding, and as shown in FIG. The tertiary molded product is placed in the cavity 20 for molding the resin R6, the upper and lower molds lie and 11b are clamped, and the resin is injected into the cavity 20 through the gates 21 and 21 for the 4th molding. are integrally formed on the surface of each metal layer 4.4 on the band portion 3.3. When the upper and lower molds lie and llb are released and taken out from the cavity 2o, the fourth molding is completed and the watch case l as shown in Figs. 1 and 2 is formed.
is obtained.

However, in such a watch case l, the metal layer 4 can be easily and reliably provided on the surface, and the metal layer 4 can be used to embellish characters, symbols, patterns, etc. very well. In particular, since the metal layer 4 is covered with the resin layer 5.6 made of transparent resin, it is well protected without being damaged or peeled off. In addition, since the metal layer 4 is printed on the base sheet 8 in advance via the release layer 9, clear and good printing is possible. Since it is arranged and provided integrally when molding the case body 1a,
It can be provided accurately and firmly without being affected by the shrinkage rate or deformation of the case body 1a after molding, or unevenness and wall thickness variations of the case body 1a.

In addition, in the above-mentioned embodiment, the case body was first molded, and the decorative layer was transferred during this molding, and then a transparent resin layer was formed on the surface of the decorative layer. When molding this resin layer, a decorative layer may be transferred to the back surface, and then the case body may be secondary molded.

Further, in the above embodiment, a resin layer for protecting the decoration layer was provided on the surface of the decoration layer, but the resin layer may not be formed.

Furthermore, although the above-mentioned embodiment has been described with respect to a watch case l in which the case part 2 and the band part 3.3 are integrally formed, the present invention is not limited to this, and the present invention is not limited to this. , (B) can also be applied to exterior parts.

That is, in FIG. 10, only the watch case 30 is molded from transparent synthetic resin, so that the watch glass 30a is also integrally molded, and the watch case 3 excluding the watch glass 30a is
A metal layer 4 is provided on the outer surface of 0 by the method described above, and
A transparent resin layer 31 is provided on the surface of this metal layer 4.

In this case, the parting plate 32 is provided on the inner upper surface of the watch case 30 in the manner described above. In addition, watch case 30
The back cover 33 attached below also has a metal layer 4 in the same manner as described above.
It is possible to provide In addition, Fig. 11 (A), C
In B), a metal layer 4 is provided on the dial 40 of a pointer type timepiece by the method described above, and a transparent resin layer 41 is provided on the surface of this metal layer 4. Even in this case, the same effects as in the above-mentioned embodiments can be obtained.

Further, in the above embodiment, the metal layer 4 was provided as a decorative layer on the surface of the exterior component, but the base sheet 8 of the thermal transfer sheet 7
If a printed layer is printed on the substrate through the release layer 9, the printed layer can be provided as a decorative layer.

Furthermore, the present invention is not limited to the above-mentioned wristwatches, but can be widely applied to other wristwatches.

[Effects of the Invention] As explained above, according to the watch exterior component of the present invention, a thermal transfer sheet is placed in a mold for molding the exterior component,
After injecting the resin and molding the exterior component body, the base sheet of the thermal transfer sheet is peeled off and the decorative layer of the thermal transfer sheet is transferred to the exterior component body, so it is not affected by the material. The decorative layer can be accurately and favorably provided on the surface of the exterior component main body, and a desirable design and appearance can be obtained.

[Brief explanation of drawings]

1 to 9 show an embodiment in which the present invention is applied to a watch case in which a case and a band are integrated, FIG. 1 is a sectional view thereof, FIG. 2 is a plan view thereof, and FIG. is an enlarged sectional view of the thermal transfer sheet, FIG. 4 is a diagram showing the thermal transfer sheet placed in the mold, FIG. 5 is a diagram showing the thermal transfer sheet sandwiched between the upper and lower molds, and FIG. 6 is 1 7 is a cross-sectional view of the main parts showing the next molding state, FIG. 7 is a diagram showing the resin injection state, FIG. 8 is a diagram showing the secondary molding state, FIG. 9 is a diagram showing the tertiary molding state, and FIG. 10 is a diagram showing the tertiary molding state. Figure 11 shows the 4th forming state.
FIGS. 12(A) and 12(B) are diagrams showing a second modified example. l, 30...Watch case, la...Case body, 2...Case part, 3...Band part, 4
...Metal layer, 7...Thermal transfer sheet, 8...
Base sheet, 9... Release layer, 11... Mold,
32...Parting plate, 33...E back cover, 40...Dial board.

Claims (1)

[Claims] A thermal transfer sheet with a decorative layer provided on the surface of the base sheet is placed in a mold for molding an exterior component, and after resin is injected to mold the exterior component body, the base sheet is peeled off to remove the decoration. An exterior part for a watch, characterized in that a layer is transferred to the exterior part body.