Abrasion resistance Ability of a coating to resist degradation due to mechanical wear by hard and rough objects (mechanical erosion) thanks to the ability to dissipate the applied mechanical energy. Abrasion resistance can be enhanced by incorporation of surface modifying additives. Abrasive media Material used in abrasive blasting to remove surface contaminants. Examples of abrasive media are sand, iron shot, crushed iron slag, glass beads, or ground nutshells. Acrylic latex Aqueous dispersion of acrylic resins. Acrylic resin Resin made by the polymerization of acrylic monomers such as acrylates (Methyl, Ethyl, Butyl) or acrylic acid. Activator Curing agent of a two pack coating system. Adhesion Degree of attachment between a coating film and the underlying material to which it is in contact. The two surfaces are held together by interfacial forces which may consist of valence forces or interlocking action. Adhesion promoter Material used to improve adhesion between materials. May be used in two different modes: by pre-treatment of a substrate, and as a component in coating formulation capable of enhancing adhesion durability due to the improvement in substrate wetting and formation of chemical bonds across the film/substrate interface. Adsorption Adsorption is the build up of a molecule at a surface. Adsorption generally occurs because different parts of a molecule have an affinity for the two different phases on either side of the interface. Aging Change of a material with time under defined environmental conditions, leading to improvement or deterioration of properties. Aggregate stability Ability to resist to various changes without flocculation and coagulation. Air drying Form of curing a coating (the most common one) by oxidation or solvent evaporation by simple exposure to air without heat or catalyst. Velocity of air-drying depends on the concentration and structure of double-bonds in the binder, the right selection of the drier (or drier system), temperature, and film thickness. Air entrapment Paint defect due to the incorporation of air bubbles into applied coating films during the application process and holding air bubbles inside the film due to a sufficiently high film viscosity. Airless spray System of applying paint by passing the paint, under high pressure, through a nozzle and by atomizing it (broking into droplets) when it enters the lower pressure atmosphere. Alkali Aqueous liquid which has a pH value of between 7 and 14. Alkyd resin Resin formed by the condensation of polyhydric alcohols with polybasic acids. Alligatoring Coating defect: surface defects of a coating film having the wrinkled appearance of alligator skin. Ambient temperature Room temperature or the existing temperature of the surroundings. Amide resin Organic compound that contains a carbonyl group bound to nitrogen. -CON- (C double bonded to O) Amino resin Thermosetting resin manufactured from amino compound and formaldehyde. Amino resins are often used as curing agents for epoxy coatings. Anti-blocking agent Additive used to lessen the adhesion of coated surfaces to another surface. Acts by producing a slight roughening of the surface. Anti-cratering agent Additive used to prevent crater formation on the paints film. . Anti-floating/flooding agent Additive preventing floating/flooding defects in coating applications. Anti-foaming agent (foam suppressant) See Foam control agent and Defoamer. Anti-gelling agent Additive used to prevent gelling in solvent or water-based coatings. Antioxidant Compounding material used to retard deterioration of coating films caused by oxidation, heat exposure… etc Anti-sagging agent Rheological additive used to prevent sagging in wet coatings where it increases the viscosity. Anti-settling agent Additive that prevents sedimentation of pigments, extenders and fillers by imparting increased low shear viscosity or a small yield value to liquid paints. Anti-skinning agent Substance added to a material to prevent or retard the processes of oxidation or polymerization which result in the formation of an insoluble skin on the surface of the wet coating. Anti-slip agent Additive which decreases the slip of surfaces. Used to eliminate the sliding of parallel film surfaces over each other or the sliding of film surfaces over substrates. Anti-static agent Additive which increases the surface conductivity of coatings and which minimizes static electricity . Architectural Coating Coating used in applications for interior or exterior surfaces of buildings. Assisted Airless Airless system that uses small amounts of air to help atomize the paint in conjunction with airless spray. Atomization Formation of tiny droplets of liquid as in the paint spraying process.