The RayVac Process
"Vacuum metallizing is the process in which a simulated chrome finish is applied to a non-porous substrate such as plastic, metal or glass. This is done under vacuum by evaporating an extremely thin layer of nearly pure aluminum onto the surface to be coated. The machine used to perform the operation is called a vacuum metallizer."
How this is done?
Carriages are mobile component parts of the total metallizing system which are used to provide the metallizing source and to hold the plastic parts to be metallized. Each metallizer has two carriages so one can be inside the vacuum chamber while the second is being prepared for the next cycle. Each carriage contains a bus bar assembly utilizing tungsten filaments.
Great care needs to be taken when charging the filaments with the aluminum clips and when rolling the carriage into and out of the metallizing chamber, to avoid premature breakage of the filament. Each of the filaments is charged with highly refined aluminum clips. The carriage is then ready to be loaded with parts for coating.
The parts to be metallized have been placed on holding fixtures, destaticized, basecoated and baked to remove the solvents from the base coat, providing a hard, smooth finish prior to the metallizing operation.
The First Step
The first step is then to place the holding fixtures onto a holding device called a spider. There are six to ten spiders per carriage. Each spider can accommodate generally between one and twelve holding fixtures at a time. This is determined by the size of the parts to be coated.
The Next Step
After all filaments have been checked, the aluminum clips are added to the wires and spiders are loaded with parts to be metallized. The carriage is rolled into the vacuum chamber. Tank operators check spider rotation to be sure parts rotate properly. The pump down cycle is started to create a vacuum in the chamber.
The Final Step
At a pressure reading of .5 microns, we are ready to "fire the plater." This is a vacuum equivalent of being 300 miles from earth into outer space. Microscopic leaks in any of the O ring seals would make it impossible to reach such a vacuum.
The tank operator activates the filament power control and heats the tungsten filament. The wires start to glow and become red hot. At this time, the aluminum clip begins to liquefy and flows out along the filament coils. The spider drive is turned on to begin rotating the spiders so all parts are properly exposed to the metallizing source.
Power is increased through a reostat-transformer heating the filaments to a temperature of 2500 degrees C. The aluminum liquid begins to vaporize and travels from the filament source in all directions. Upon hitting the parts to be coated, the aluminum molecules penetrate the base coat providing a dry, cool, and brilliant mirror-like surface.
Filament power is turned off, the chamber is flooded with air and spider rotation is stopped. Out rolls the metallized parts which are then unloaded and ready for top coat or final inspection and pack.
The Newest Generation
Our newest vacuum metallizing and polymer deposition systems are designed for trouble free, high speed coating operation, controlling the metal and topcoat consistently from load to load. This equipment can eliminate the need for conventional organic coatings thus reducing solvent emissions.
The Computer controlled technology is widely used in the manufacture of road reflectors, automotive headlamps and taillights, lighting products such as reflectors, louvers, LED lighting products, novelties, fish lures, cosmetics, point of purchase displays, interior automotive bezels and reflectors, and a wide variety of electronic and household products.
Other metallizing systems are specifically designed for RFI/EMI shielding thus providing valuable service to the electronic and computer industries.
|Examples of Metallized LED Lighting Reflector
|Various Automotive Products Processed by RayVac Plastics