METHOD FOR REMOVING STAIN FROM WATER-IMPERMEABLE MATERIAL

摘要

PURPOSE:To economically and efficiently remove stain from a water- impermeable material in a simple operation without detriment to the quality of the material. CONSTITUTION:A layer for removing dry stain which contains a water-soluble alkali metal silicate as the effective constituent is deposited on a water- impermeable material such as a tent cloth. A water supply material is fed to the layer to hydrate the alkali metal silicate to thereby form a hydrated layer so that the stain is incorporated by absorption into the hydrated layer. This hydrated layer is then removed from the water-impermeable material.