| 摘要 |
An apparatus (10) for applying polymerized coatings to can bodies (12) has a means (13) for applying the coating as a liquid containing a polymerizable or polymer coating material in one or more vacuum liquifiable solvents. The coated can bodies (12) are heated in a confined space (22) a sufficient extent by induction coils (20) to substantially exclude air at entrance (16) to vacuum chamber (18). Second induction coils (28) heat the can bodies (12) further to flash evaporate the remaining vacuum condensable solvent from the coatings and to cure the coatings. The solvent vapor is condensed in the vacuum chamber (18) and condensers (68, 72, 76). A means (50) supplies a sufficient quantity of water at exit (42) from the vacuum chamber (18) to substantially exclude air at the exit (42). The can bodies (12) vaporize the water and the water vapor excludes the air. The water vapor is condensed under the vacuum of the chamber (18) by condenser (52). Because only the vacuum condensable solvent vapor is introduced to the vacuum chamber (18) at entrance 16 and only the water vapor is introduced to the vacuum chamber (18) at the exit (42), and both vapors are condensed in the vacuum, only a small vacuum pump (50) is required to maintain the vacuum in the chamber (18), and the pump is operated only when the vacuum decreases. Curing the coatings under vacuum makes them very high quality over a wide thickness range.
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