Coatings, pigment volume

Flake zinc pigments have a barrier effect and also act by a cathodic anticorrosive mechanism. Compared with zinc dust coatings, flake zinc pigments are formulated with lower pigment volume concentrations [5.178]. 

One coat of primer, formula 84-47, followed by an experimental red deck paint similar to that specified in specification (7), formula 23, except that sufficient chlorinated paraffin was substituted for the alkyd resin solid to yield a chlorine content of 35 > in the nonvolatile vehicle without altering the pigment volume. This paint was formulated by the Paint Research Section it has not been accepted for naval use. 

The formation of hydrolysis products, in the case of zinc phosphate, depends on the permeability of the protective coating. The permeability of the protective coating itself is influenced by the type of resin used, and in particular, by the PVC (Pigment Volume Concentration). This means that the choice of resin, pigments and fillers and the complete formulation have an important influence on the corrosion protection behavior of protective coatings containing zinc phosphate [5.69]. 

A reduction in the volume of water needed at the paper machine is almost impossible because paper formation will be disturbed if the consistency of the pulp suspension becomes too high. Currently, the stock suspension (i.e., pulp and additives) in the head box of a paper machine contains 97%-99.9% water. The constraint of maintaining pulp suspension consistency means a reduction in water intake has to be realized by reusing the process water. Due to the different purposes and applications in which water is used, the water quality demands vary considerably. Membrane processes can be chosen to produce a specific water quality and are attractive alternatives to facilitate the reuse of water, either alone or combined with biological processes or other chemical and physical processes. In addition, membrane processes are an efficient way to recover raw materials, e.g., coating pigments, from effluents. 

Pigments could influence the mechanical properties of a film as well as the dissolution behavior of a drug substance from coated tablets or pellets. According to Rowe different pigments should be compared on the bases of the pigment volume concentration (PVC), which takes density differences into account [Eq. (3)],... 

Low Shear Rates. Small-particle latices provide higher critical pigment volume concentrations and thereby greater coating formulation latitude. Their viscosities are, however, too high at low shear rates and too low at high shear rates to provide acceptable applied film properties. This phenomenon is illustrated in part in Figure 14. The latices used in this study (26) included three commercial binders (half symbols) the others were ex-... 

F.B. Stieg, Influence of PVC [pigment volume concentration] on paint properties. Prog. Org. Coat. 

Curling and cracking coating too thick/lack of plasticizer additives/air humidity too low or air too dry/temperature too low/pigment volume too high/Deborah... 

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