Chemical vapor deposition allows ultra-thin lubricious coating for mold components
Published: July 12th, 2012
A chance meeting at a trade show has brought a coating technology that originated in the semiconductor industry into injection molding, giving mold components an inert, lubricious coating that eliminates the need for grease in medical and packaging applications, among others.
The Poco Graphite technology, marketed to the injection molding industry by PCS Co. as UltraC coatings, creates what the companies call diamond-like carbon (DLC) coatings that reportedly enhance durability and mold productivity while reducing friction and corrosion.
At Plastec East 2011, PCS and Poco Graphite were nearly neighbors as exhibitors and over the course of the show and several discussions perceived the potential for a collaboration to bring the DLC coating into injection molding. Following a formal meeting in December of that year, the companies moved forward and commercialized the UltraC line of coated mold components at NPE2012.
The coatings are derived from a proprietary mixture of gases applied to the components via plasma-enhanced chemical vapor deposition (PECVD). The result is a chemical bond to the substrate, which can be in a variety of materials, including metal and plastic. The companies stress the result is a chemical bond on molecular level, not etching. Entegris, which owns Poco Graphite, says the high-performance coatings are formed using a proprietary low temperature (<150°C) process that deposits the layer in a high-vacuum environment.
Conformally coating the exposed surface with a layer that is 80 millionths of an inch thick, the technology allows mold components to be coated without having to make any tool adjustments.
PCS says potential applications in molding include:
- Ejector pins
- Cores and sleeves
- Thread cores
- Cavity surfaces
- Wear plates
Beyond injection molding, PCS is promoting potential use for blowmolds and aluminum die casting. Also, since it's a low-temperature process, some plastics can be coated as well. In terms of benefits, PCS sites:
- Reduced coefficient of friction
- Short cycle times since galling in components is eliminated
- Complete seal of the surface, making it inert to moisture/gases
- Corrosion resistance