杜邦Zonyl.docVIP

DuPont? Zonyl? Penetrating Sealers The Solution for Protecting Porous Surfaces The preservation of porous substrates is one of DuPont’s major preoccupations. DuPont, a world leader in fluorochemistry has developed a line of Zonyl? fluorinated additives that provide a durable and transparent protective barrier against oil and water stains on stone, unglazed tile, terra cotta, and other porous masonry and mineral surfaces. When added to penetrating sealer formulations, Zonyl? fluorinated additives chemically bond to the surface, providing a transparent vapor-permeable coating with no effect on the appearance of the surface. This document discusses problems arising in the treatment of porous materials, why it is necessary to treat them against external effects, and some solutions developed by DuPont. Advantage of Water and Oil Repellent Products Definitions A water repellent is a product intended to limit the penetration of water into the pores and capillaries of a surface without altering its mechanical and aesthetic qualities. Its action is to make the material hydrophobic, meaning that it does not allow itself to be penetrated by water. An oil repellent is used to protect materials from grease stains (petrol, lubricating oil, edible oil, etc.). Material that has been made oleophobic does not allow itself to be penetrated by oils. A good water repellent and oil repellent must: create a surface that is impermeable to water; i.e., reduce capillary activity create a surface that is impermeable to oil or grease stains ? not change the permeability to water vapor not change the color or texture of the surface, even after aging have an adequate depth of impregnation Mode of Action of Zonyl? Fluorinated Additives Concept of Wettability A surface has a greater tendency to become stained when a liquid (water, grease, grape juice, etc.) can easily wet it. This phenomenon is best illustrated using the wettability concept. The wettability of a surface can be described by the a