The present invention relates to a method of in-mold decoration, and more particularly to a method of forming an injection-molded plastic layer and a printed pattern on both sides of the thin-film substrate respectively.
With the progress and improvement of technology, the new generation of electronic products not only have better execution performance and more friendly user interface but also have improved designs so as to emphasize their unique characteristics and styles for thereby changing the former impression on these electronic products and raising the marketing percent via their diverse characteristics and charms on designs.
Under such a tendency, the in-mold decoration (IMD) has been become a popularly employed technology in the field of surface decoration. In the in-mold decoration procedure, a shapeable film is employed to replace the conventional manufacture processes including painting, printing, heat pressing, and chromium plating steps which are performed after the components are shaped. Therefore, the surface effects and patterns of the products can be increased and the required steps for manufacturing the products can be also decreased. Accordingly, the taken manufacture time and the production cost can be significantly reduced. Therefore, the method of in-mold decoration is widely applied to the mobile phones, the laptop computers, the home appliances such as washing machines, and even the dashboard and case decoration of cars.
Referring to
It is worthy to note that the taken manufacture time and cost are increased significantly since the step of printing the anti-ink spreading layer 16 are repeated several times to thereby prevent the injection molded plastic layer 18 from damaging the pattern 14 on the thin-film substrate 10.
Besides, if it is desired to manufacture a 3D-shaped product by using the in-mold decoration method, a heat-pressing procedure must be utilized to shape the thin-film substrate via the heat-pressing mold before the performing of the injection molding procedure. However, if the surface of the utilized thin-film substrate has been hardened by hardening treatment, the crack phenomenon will occurs easily on the surface of the thin-film substrate during the heat-pressing procedure, resulting in that the height and the R angle of the 3D-shaped products are confined so it is unable to fulfill the requirements of industrial designers.
The present invention provides a method of in-mold decoration, which comprises the following steps of providing a thin-film substrate having a first surface and a second surface opposed to the first surface, printing a pattern on the first surface of the thin-film substrate, coating a hard-coating layer on the pattern, applying a UV light to harden the hard-coating layer, cutting the thin-film substrate, and performing an injection molding procedure to form a plastic layer on the second surface of the thin-film substrate.
In one preferred embodiment, if it is desired to manufacture a 3D-shaped product by applying the method of in-mold decoration (IMD) of the present invention, a heat-pressing procedure is further performed between the step of coating the hard-coating layer and the step of hardening the hard-coating layer so as to provide the thin-film substrate with a 3D shape. In addition, a hot-air drying treatment is further performed on the hard-coating layer coated on the first surface before the performing of the heat-pressing procedure so as to initially dry the hard-coating layer.
a-2d show a process of manufacturing a planar product in accordance with the method of in-mold decoration of the present invention;
a-3d show a process of manufacturing a 3D-shaped product in accordance with the method of in-mold decoration of the present invention;
Referring to
Thereafter, as shown in
In one preferred embodiment, in order to prevent the pattern 22 from being damaged due to the occurrence of ink spreading phenomenon in the sequent injection molding procedure, an anti-ink spreading layer 21 is optionally printed on the first surface 20a of the thin-film substrate 20 before performing the step of forming the pattern 22 on the first surface 20a of the thin-film substrate 20. And, after the anti-ink spreading layer 21 is formed, the pattern 22 is then printed on the upper surface of the anti-ink spreading layer 21. The above-described anti-ink spreading layer 21 is also formed by the roll-to-roll method.
Besides, after the pattern 22 is printed on the thin-film substrate 20, a protection film is optionally adhered to the first surface 20a of the thin-film substrate 20 for covering the pattern 22 so as to protect the pattern 22 printed on the thin-film substrate 20 against scratch or pollution since the thin-film substrate 20 that has the pattern 22 printed thereon is stored by the roll-to-roll method. After the pattern 22 is covered with the protection film, the thin-film substrate 20 is then stored by the roll-to-roll method, wherein the protection film is adhered thereto by using a back-gluing machine.
Thereafter, as shown in
Certainly, if the step of adhering the protection film to the thin-film substrate 20 is performed immediately after the step of printing the pattern 22, the protection film must be stripped off first before the step of coating the hard-coating layer 24 on the pattern 22. In addition, in order to protect the hard-coating layer 24 against pollution, another protection film can be further optionally adhered to the first surface 20a of the thin-film substrate 20.
Thereafter, as shown in
It is specially noted that there is a need to manufacture a 3D-shaped product by applying the method of in-mold decoration (IMD) of the present invention, a heat-pressing procedure is additionally performed between the step of coating the hard-coating layer 24 and the step of irradiating the hard-coating layer 24 with the UV light so as to provide the thin-film substrate 20 with a 3D shape.
Referring to
After the hot-air drying treatment, the initially dried hard-coating layer 24 helps the sequent shaping of the thin-film substrate 20. Thereafter, as shown in
After the heat-pressing procedure is completed, as shown in
After the above-described coating and irradiating procedures are completed, as shown in
Referring to
Thereafter, a step S2 is performed for printing ink on the thin-film substrate 20 so as to form a pattern 22 on the surface of the anti-ink spreading layer 21 by the roll-to-roll method. Similarly, after the pattern 22 is printed thereon, the step S20 can be performed on the thin-film substrate 20 with a temperature range between 65 and 90 degrees centigrade for about 5 to 15 minutes so as to dry the ink of the pattern 22.
Thereafter, a step S3 is performed for forming a protection film on the surface of the pattern 22. Certainly, as described above, this step S3 is optionally omittable. Thereafter, a step S4 is performed for coating a hard-coating layer 24 on the surface of the pattern 22. After the coating procedure of the hard-coating layer 24 is completed, a step S40 is performed for performing a hot-air drying treatment so as to initially dry the hard-coating layer 24. Then, a step S5 is optionally performed for forming a protection film on the surface of the hard-coating layer 24 on demand.
If it is desired to manufacture a 3D-shaped product, a step S6 is additionally performed for shaping the thin-film substrate 20 by a heat-pressing procedure. Thereafter, a step S7 is performed for completely hardening the hard-coating layer 24 by irradiating the hard-coating layer 24 with the UV light.
Thereafter, a step S8 is performed for cutting the thin-film substrate 20 by a cutting procedure. And, a step S9 is performed for forming a plastic layer 26 on a second surface 20b of the thin-film substrate 20 by using an injection molding procedure, and thereby obtaining the final product.
The method of in-mold decoration of the present invention has considerable advantages. First, the injection-molded plastic layer and the printed pattern are located on both sides of the thin-film substrate respectively so the injection-molded plastic layer does not touch the ink directly and thus the occurrence of ink spreading phenomenon can be reduced effectively. As a result, the required number of times for printing the anti-ink spreading layer can be significantly reduced, thereby decreasing the cost effectively and increasing the competitiveness of the injection molded products.
Moreover, the hard-coating layer can be initially dried by the hot-air drying procedure before the step of shaping of the thin-film substrate by the heat-pressing procedure. Then, the UV light is utilized for completely hardening the hard-coating layer so as to meet the physical property requirement for surface. In this way, the shaped thin-film substrate can maintain its 3D shape and thereby avoid the occurrence of deformation caused by insufficient surface hardness. Moreover, in the heat-pressing procedure, the thin-film substrate has comparatively less ability to adhere to the heat-pressing mold so the production performance of the heat-pressing procedure can be thus increased.
Furthermore, the thin-film substrate still has considerable expansibility after the initial drying of the hard-coating layer so the thin-film substrate can be shaped into the required 3D shape via the heat-pressing mold and then hardened by the UV light irradiation. As a result, the surface of the thin-film substrate is prevented from the occurrence of cracks caused by excessive surface hardness during the heat-pressing procedure.
While the preferred embodiment of the invention has been set forth for the purpose of disclosure, modifications of the disclosed embodiment of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
97318531 | Oct 2008 | TW | national |