Method of Applying In-Solution Oil Repellent

A method of applying to a predetermined region of a machine component a low-viscosity in-solution oil repellent obtained by dissolving in a low-viscosity, rapid-drying solvent an oil-repellent resin whose principal constituent is a fluoroplastic resin component, the method utilizing an applicator device made up of

• an applicator tip internally having a microthin flowpath through which the low-viscosity in-solution oil repellent can flow, and having the elasticity to be able, by releasing stress associated with the repellent-application operation, to recover its original shape from deformation caused by that stress, the microthin flowpath dimensioned to impart viscous resistance to the low-viscosity in-solution oil repellent when the repellent flows through the flowpath interior,
• a contacting piece disposed in an end portion of the applicator tip, in a position enabling a contacting surface of the piece to be pressed against the predetermined region of the machine component during the repellent-application operation, wherein one end of the applicator-tip flowpath opens on the portion of the contacting piece where, or in the vicinity of where, the piece contacts the predetermined region of the machine component, and
• a reservoir in which the in-solution low-viscosity oil repellent is stored and which is connected to the other end of the flowpath;
• the in-solution oil-repellent application method comprising:
• with the contacting surface of the contacting piece pressed against the predetermined region of the machine component, causing relative movement of the contacting piece superficially on the machine component along the predetermined region;
• wherein the viscous resistance imparted to the low-viscosity in-solution oil repellent by the microthin flowpath delays, to an extent enabling the repellent-application operation, the outflow of the oil repellent from the opening in the applicator-tip flowpath.