Abstract: A wash tank adapted for use with a carbon dioxide cleaning medium has a body member having a front opening formed therein, the body member having side walls and a back wall opposite the front opening. The side walls terminate in a front body member edge portion that defines the front opening. The edge portion serves in the sealing mechanism, as discussed below. A substantially cylindrical basket is disposed within the body member for rotation about a generally horizontal axis. The basket has a front opening formed therein, and has a side wall and a back wall opposite the front opening. The basket side wall terminates in a front basket edge portion defining the basket front opening. The said basket edge portion is spaced forward from the body member edge portion when the basket is positioned in the body member, serving to prevent loose garments or materials placed within the basket from becoming caught in the seal and interfering with seal integrity.

Abstract: A method of treating a substrate comprises contacting a surface of said substrate, with a pressurized fluid comprising carbon dioxide and a surface treatment component, the surface treatment component being entrained in the pressurized fluid and contacting the surface so that the surface treatment component lowers the surface tension of the surface of the substrate and treats the substrate. The contacting step is preferably carried out by immersion, the fluid is preferably a liquid or supercritical fluid, the substrate is preferably a metal or fabric substrate, and the surface treatment component is preferably a fluoroacrylate polymer.

Abstract: A method of dyeing a substrate in carbon dioxide comprises the steps of (a) providing a dye composition comprising carbon dioxide, a dye, and a surfactant, the surfactant included in an amount sufficient to solubilize, emulsify or disperse the dye in the carbon dioxide; and then (b) dyeing said substrate with said dye composition.

Abstract: A method for dry-cleaning articles such as fabrics and clothing in carbon dioxide comprises contacting an article to be cleaned with a liquid dry cleaning composition for a time sufficient to clean the fabric. The liquid dry-cleaning composition comprises a mixture of carbon dioxide, water, and an end-functional polysiloxane surfactant. After the contacting step, the article is separated from the liquid dry cleaning composition. The method is preferably carried out at ambient temperature.

Abstract: A method for dry-cleaning articles such as fabrics and clothing in carbon dioxide comprises contacting an article to be cleaned with a liquid dry cleaning composition for a time sufficient to clean the fabric. The liquid dry-cleaning composition comprises a mixture of carbon dioxide, water, a surfactant, and an organic co-solvent. After the contacting step, the article is separated from the liquid dry cleaning composition. The method is preferably carried out at ambient temperature. The surfactant may be either one that contains a CO.sub.2 -philic group or one that does not contain a CO.sub.2 -philic group. The organic co-solvent is preferably an alkane that has a flash point above 140.degree. F.