ENGEL Streamlines Clear-Coated Parts Production

Clearmelt is a high-volume manufacturing system that combines both thermoplastic injection molding and thermoset polyurethane (PUR) reaction injection molding, with innovative mold design and dedicated automation to efficiently and economically produce scratch-proof, attractive, clear-coated components, such as finished automotive interior trim. For example, when using a sliding-platen two-cavity mold a thermoplastic substrate is molded, while, simultaneously, the empty mold cavity is sprayed with a PUR mold release agent. When moved into position, a clear PUR coating is injected onto the molded thermoplastic part and cured. Then, when that portion of the mold opens, the finished part is robotically removed, oriented, and stacked while, simultaneously, a thermoplastic substrate is molded in the other, empty, closed cavity.

For a more continuous clear-coated parts production using the clearmelt process, a multicavity rotary-platen mold can be used.

Unlike more conventional spray-coating and varnishing methods, ENGEL clearmelt reduces finishing requirements, while also reducing the cost of labor, materials, and waste disposal. Also, conventional spray-coating and varnishing technologies can require time-consuming and expensive multiple coating methods, which often can result in a substantial number of rejects. And, unlike clearmelt, such conventional technologies are incapable of producing aesthetically pleasing three-dimensional effects at coating thicknesses of less than 0.5 mm.

ENGEL's clearmelt technology also may advance into the field of consumer electronics-enhancing the aesthetically appealing appearance of finished electronic parts, while also providing more opportunities for increasing integrated part functionality.

For example, ENGEL has demonstrated the production of functional electronic components that incorporate a capacitive foil overmolded with a clear, protective, ultra-high-gloss PUR film. Electronic circuits can be actuated simply by touching the respective symbol beneath the thin PUR film. ENGEL has also demonstrated the versatility of clearmelt technology by molding sample products with a non-functional, but aesthetically pleasing appearance, including clear-coated parts with carbon- and wood-finished substrates.