Wetting of substrate

Viscosity decrease at elevated temperature provides more efficient wetting of substrate... 

Curve 1 (Fig. 3.118) corresponds to a complete wetting of substrate A and stable films within the whole range of thicknesses - from diluted adsorption layers to thick films with interfacial tension... 

Low surface tension causes excellent wetting of substrate which is required for good adhesion of the coating to the surface. Good adhesion promotes good corrosion resistance, impact resistance, and chip resistance. 

Low boiling solvents like alcohols or low boiling ketones may be added to lower the surface tension of the PEDTPSS dispersion, thereby increasing the wetting of substrates. These additives... 

Block copolymers having one hydrophobic and one hydrophilic segment can be used as surfactants Emulsification of aqueous and non-aqueous components, wetting of substrate surfaces and foam stabilisation Riess (1999)... 

These are minute holes which are formed during the application of a paint, which exposes the underlying substrate. The flow of applied paint is not continuous due either to poor mixing of two pack materials or insufficient agitation leading to insufficient wetting of substrate. 

Wetting of substrates is defined as the displacement of adsorbed air at the substrate surface by a liquid coating or ink material. Satisfactory wetting pro-... 

Proper wetting of substrates is mandatory for a good adhesion (refer to the chapter Theory of adhesion in Volume 2). 

Uses Silicone-ffee leveling agent for powd. coatings improves wetting of substrate prevents craters, fish eyes, orange peeling anti-floal Properties Powd. 

Water-Based Writing Inks. These consist of very fine pigment dispersions in aqueous media containing small amounts of glycol or glycerol and a dispersing aid. They dry mainly by evaporation and quick wetting of ceUulosic fibers in paper substrates. 

Adhesion to Metals. For interaction between coating and substrate to occur, it is necessary for the coating to wet the substrate (107). Somewhat oversimplified, the surface tension of the coating must be lower than the surface tension of the substrate. In the case of metal substrates, clean metal surfaces have very high surface tensions and any coating wets a clean metal substrate. 

As a result of the reduction in viscosity, the adhesive is now fully activated. The heating of the bond line ceases. The viscosity of the adhesive is now low enough so that the adhesive can be mated with a second substrate, and proper wetting of the second substrate can occur. 

Absorption and wetting. Generally, it is necessary for the adhesive resin to wet the substrate surfaces. The surface energy of the composite substrate must be greater than the surface energy or surface tension of the resin in order for effective wetting to occur. 

When the fiat substrate is not wet (5 < 0), the wetting of a rough surface requires that the spreading coefficient... 

The above equations (68) and (69) do not guarantee wetting of a rough substrate and express only the fact that the interfacial free energy of a thick... 

Localised adhesion failure occurs most easily where broken scale or rust, or deposits of salts, have impeded wetting of the metal substrate by the film-forming constituents of the paint. 

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