Towards the end of the 20th century, the competition between China's automobile joint venture brands and foreign brands began to intensify. Automobile manufacturers expect to use a process that does not require much higher cost than spraying to achieve surface decoration patterned, colorful and personalized to attract consumers. In such a big environment, water transfer printing began to prevail. In the past ten years, water transfer printing has occupied almost 100% of the market.
Water transfer: the plastic substrate has been molded and embossed on the water surface of the water-soluble film, transfer film on the pattern, and then transparent varnish to protect its pattern and the surface to do gloss adjustment. The process is transferring - film removal - drying - spraying top coat.
The advantage of water transfer is that it does not require additional molds, and the cost per piece is low. However, its fatal disadvantage lies in the molding process when encountering a stretching shape, the pattern deformation is very large, so it is only suitable for irregular large patterns, such as mahogany, marble, camouflage pattern.
When the water transfer printing of imitation mahogany overwhelmingly in the various types and grades of the car after the application, resulting in imitation mahogany application of the flood. Consumers also began to produce aesthetic fatigue, expect something different to appear, such as rule patterns, small patterns and so on to give a person a delicate, regular, rational feeling. At the same time, with the community's environmental protection requirements, the water transfer printing production line of environmental pollution is also increasingly questioned, other more environmentally friendly, more diverse forms of expression of the surface decoration process began to appear.
IMD (In-MouldDecoration, in-mold decoration) process developed by the Japanese photo printing company (NisshaPrinting), the initial application is in the laptop, so that the black paste of the computer shell becomes colorful. However, when this process appeared, it was only applicable to relatively flat surfaces and could not meet the larger tensile surfaces. With the further increase in consumer demand, the IMD decorative part can not only be used for trim, but also applied to the center control panel and other more complex shapes, which gave birth to the process of IMD subdivision (IMF, the automotive industry called INS).
IMD (In-Mould Decoration), also known as IMR (In-Mould Rolling, in-mold transfer), with the appearance of the IMD film (ring material) is installed in the film transfer machine, and the film transfer machine is fixed in the injection molding machine, in the injection molding to let the film into the middle of the mold, after the mold is closed to allow the injection of adhesive material to let the film affixed to the mold while transferring the pattern to the mold. After the mold is closed, the adhesive is injected and the film is laminated to the mold, while the pattern is transferred to the product and the adhesive is molded. The process is film conveying - film positioning, picking up the molded part - injection molding - post-processing, cleaning up the flying edge.
INS (Film Insert Moulding): The INS film with appearance effect is pre-absorbed/high-pressure molding, the excess film edge is punched, and then the punched film shell piece is placed in the injection mold for injection molding. The process is heating the film - high pressure air molding (or suction molding) - knife die cutting - the molded film shell sheet into the mold cavity - close the mold, injection molding - open the mold, complete the assembly.
With the further improvement of consumer requirements, decorative film will not only meet the visual multi-fancy color enjoyment, but also need to be suitable for tactile feeling of convexity and concavity, glossy changes in the design of the dimensions of the laser laser engraving three-dimensional pattern and texture, so gave birth to a new type of film, which in turn, promote the film, the printing industry, to have a new process to achieve.