| 摘要 |
1,126,836. Hermetic casings for electrical components. ITT INDUSTRIES Inc. 1 Sept., 1967 [7 Sept., 1966], No. 40021/67. Heading H1K. [Also in Division D1] A porous casing 8, e.g. of epoxy resin, enclosing an electrical component such as a semi-conductor diode 3 is hermetically sealed by impregnating the casing 8 with a curable liquid impregnant such as a varnish, so that the impregnant enters the pores 7 of the casing 8, immersing the casing in a solvent which dissolves the impregnant on the outside of the casing 8 and on the leads 1, 2 but which fails to remove the impregnant retained in the pores 7 by surface tension forces, and finally curing the retained impregnant by heating the casing. Prior to initial impregnation the casing 8 may be heatdried in vacuo. The impregnant may be driven into the pores 7 by subjection to a pressurized atmosphere, or by immersing the casing in a bath of impregnant while applying vacuum to the surface thereof. |
