A method of removing contaminants from the surface is disclosed. The method comprises coating the surface with a surface active agent having a first surface energy and into which the contaminants are combined, applying thereover a higher surface energy colloidal sol and then allowing sufficient time for the first surface energy material with the contaminants combined therewith to migrate through the colloidal sol so as to remove the contaminants from the immediate vicinity of the substrate surface. The surface may then be treated by exposing it to an acid or base to remove the migrated surfactant layer thus removing the trace of contaminants.
A cleaning device and a method for effecting cleaning, in which a pretreatment agent is applied to a cloth affixed over a vertical surface of an erected body made of a rigid material, the pretreatment agent being adapted to improve the cleaning effect of a detergent, and then, the detergent is applied to the cloth, after which, all the pretreatment agent, detergent, and dirt are sucked and removed from the cloth. Hence, a high cleaning effect can be achieved without causing any deterioration of the cloth.
An improved process for forming devices utilizing patterned organic semiconductor films is provided. The process involves treating a surface to selectively provide regions of greater affinity and lesser affinity for an organic semiconductor or an organic semiconductor solution. When the organic semiconductor, or solution comprising the semiconductor, is deposited on the treated surface, either the organic semiconductor or the organic semiconductor solution dewets from the lesser affinity regions or the resultant film adheres only weakly to the lesser affinity regions such that selective removal is readily performed. And even where such removal is not performed, the portions of the organic semiconductor film overlying the greater affinity regions exhibit higher mobility and better film continuity relative to the other portions of the film.
