| 摘要 |
<p>A new compsn. formulated to provide a non-toxic sealant coating (A) over a liq. (B) releasing vapours or toxic emissions by evapn. or reaction with atmos. agents. The compsn. comprises the following mixt: (1) (C) - a liq. of low vapour pressure, miscible or immiscible with (B), and chemically inert towards (B); and (2) (D) - low density solid particles - inert to (B) and (C) chosen to increase the density of liq. (C) relative to (B) to constitute a mixt. (A) which will float on (B), even if (C) is miscible with (B) and/or has a density approaching (or even greater than) (B). In this case, miscibility is prevented by previous wetting of the solid particles by (C). Also claimed is the procedure for creating a sealing layer (A) over the liq. (B). Cpd. (C) comprises at least one cpd. chosen from di-octyl phthalate, di(2-ethylhexyl)phthalate and the silicones. The solid particles (D) are glass micro-balls. The liq. (C) comprises 95-81% (wt.) of the mixt. (C)+(D), and the particles (D) 5-19% of the mixt. The compsn. also contains a thixotropic agent (E), inert vis-a-vis liq. (B) to increase the viscosity of (C) (if need be), giving a pasty consistency, to reduce or nullify convection phenomena between (B) and (C). The agent is pref. a hydrophobic silica gel, which limits the interaction of atmospheric humidity vis-a-vis the sealing layer (A) and liq. (B). and attenuates sepn. phenomena of liq. (C) : solid (D). The amt. of agent (E) is up to 5% (wt.) of the mixt. (C)+(D). Also included is a spreading agent (F), (inert vis-a-vis liq. B) which comprises a low viscosity liq. favouring the spreading of (A) over (B) and joining around obstacles. <IMAGE></p> |
