Decorative surfaces for vehicle interiors
Are you familiar with the terms IMD, IMF or IML to refer to decoration technologies? Do you have doubts about the differences between them? This article is for you!
IMD, IMF, IML... many similar acronyms to refer, sometimes incorrectly, to different techniques of decoration with films, but with clear differences between each of them. In this article, we are going to clarify the differences between the different technologies in a clear way and provide examples so that you don’t have any doubts again.
Let’s start from the beginning. What does each term mean?
• IMD: In-Mold Decoration. This technique consists of a transfer of inks from the film to the part to be decorated during the injection process. The film is only a support, it’s not part of the decoration of the deco once the process is finished. It’s recommended for parts without aggressive shapes. It should be noted that you need specific injection tools and equipment.
The following image details the main steps of the IMD process:
The first image shows a roll feeder with decorated film that unwinds between the fixed part and the moving part of the mold (image 2) after each injection cycle, during the mold opening time. The film is heated (this phase is optional and depends on the geometry of the piece) and vacuum sucked into the mold cavity. Once the film is heated, the mold is closed and the injection takes place, the inks are transferred to the injected mass during the injection process.
Once the piece is extracted from the injection mold, it may be necessary to cure the protective varnish with a U.V. oven. Also, when the processed part is extracted, the film advances one format, and the next injection cycle is carried out.
· IMF: Insert Molding Forming. In this case, an insert overholding is used (previously decorated and thermoformed film by vacuum or high pressure). In this case, the distortions can be more aggressive, and again, you need specific injection and thermoforming tools.
The different steps of the IMF process are graphically shown below.
The process consists mainly of 4 steps.
1. Creation of the decorated film, which is carried out by silk-screen printing (image 1) or by roto-engraving technique, generally on film without prior decoration, then the upper layer of protective varnish is cured.
2. The decorated film is molded through a high-pressure molding process.
3. The excess film is cut and the insert or inserts resulting from the cutting operation of the previously decorated and molded film are obtained. Laser cutting techniques, male-matrix….
4. This insert is placed into the cavity of the injection mold, where the injection process is carried out, generally through the B face of the insert. The resulting part is made up of a mass of plastic material + a layer of decorated film (insert).
· IML: Insert Molding Labelling. We could consider this technology as a variant of IMF technology. Its use is indicated for nearly flat decorated parts. Therefore, the pre-injection molding of the decorated film is not necessary.
Some examples of the different technologies:
IMF, a versatile and efficient technology for multiple parts
Let's research a little more about IMF technology. We consider to be one with the greatest potential and bringing the most advantages over the others.
- Savings in the number of injection molds.
- Possibility of partial decoration of parts.
- Multiple inserts in one part.
- Different decorations using the same tooling (decoration customization).
- Possibility of adding functionality to the decorated part (plastronics).
- Backlighting and day & night effects.
Grupo Antolin has developed, among other components, a Capacitive Pad that includes all the functionalities described above.
There are also a number of considerations to consider before starting to use this technology:
- Know the limits of the decorated area.
- Consider the fixing system of the insert.
- Multiple injection gates may be required.
- Sequential injection may be necessary.
Grupo Antolin, together with its strategic partner Walter Pack, offers different alternatives for both interior and exterior decoration.