In Mold Decorating, commonly known as IMD, is used to mold high-precision plastic parts with exceptional color and appearance. The process involves placing a decorative element into an injection mold and molding behind and around it. The decorative element becomes an integral component of the molded part. It is a form of insert molding, albeit a highly specialized one.
One type of IMD process involves the use of a heat transfer foil to deposit a pre-printed decorative element into the surface of a molded part. Developed by the Nissha Company in Japan, it provides all the benefits of injection molding with the added advantages of modern digital printing. It is one of the few manufacturing processes that allows for a true chrome finish on a molded plastic part. In addition, the decorative element can have multiple layers, including hard coat and anti-microbial treatments.
The frame of this cell phone lens assembly was made using this process, using a proprietary metallic ink that was RF transparent. The clear lenses were attached to the frame using ultrasonic welding, and the assembly was then attached to the phone housing via heat staking.