Zinc-rich paints

Painting with aluminium-pigmented paint is considered in Chapter 14 because its properties are essentially those of a paint and not of a metallic coating in this respect aluminium paint differs from zinc-rich paint which can be formulated to provide galvanic properties similar to those of metallic zinc. 

The outstanding virtue of zinc-rich paints is simplicity in application. No special equipment is required and the operation can, of course, be carried out on site, large or small structures being equally suitable for treatment. While there is some evidence that the zinc-rich paints will reduce iron oxides remaining on the steel surface, proper surface preparation is as important here as with traditional paints if the best results are to be achieved. The main use of zinc-rich paints is to protect structural steel-work, ships hulls, and vulnerable parts of car bodies, and to repair damage to other zinc coatings. 

Muller, K. A., Spontaneous Combustion of Zinc-rich Paint Mixtures, Washington, API, 1969... 

Bitumen over zinc rich paint 1 coat 20pm... 

Taking the hydrogen evolution experiments and the mechanical detachment experiments as a guideline, experiments were carried out using these on a paint known to exhibit mud-cracking (predetermined frequency bands). When the pool of zinc-rich paint first began to dry, cracks formed in the surface leaving the paint below fluid. 

Iron phosphide anticorrosive pigments are recommended by manufacturers as replacement materials for zinc dust to reduce the price of zinc-rich paints [5.103]. For toxicological data, see Section 5.2.14. 

The epoxy-polyamide system may also provide a base for paper and board coatings applied by rotogravure or roller-coating techniques. It is useful for coating plastics and particularly valuable as a resin system for zinc-rich paints. It may be formulated with exempt solvents specified under Rule 66 (37). Higher solid formulations, particularly those formulated with fatty amido amines, are available. These formulations reduce solvent pollution and allow for higher film builds (37, 38). 

Paints and Coatings. Ethoxysilanes are used in high temperature, zinc-rich paints (see Paint) (51,52). Methyl- and phenyltrialkoxysilanes are used to prepare abrasion-resistant coatings for plastics (53), particularly polycarbonate (54,55), and dielectric coatings and seals for high voltage electrical components, including television tubes. 

Galvanized-steel bars can be welded, but loss of the zinc coating may take place in the welded zone the application of a zinc-rich paint should be recommended after cleaning of the welded area. 

As indicated in Table 10.18, a zinc-rich primer is often recommended. It can be an organic zinc-epoxy or an inorganic zinc-ethyl-silicate primer. Zinc-rich primers are also used as so-called shop primers, or prefabrication primers, for temporary protection of semi-manufactured steel goods. After fabrication, e.g. of welded steel structures, the shop primer surface must be cleaned (degreased), and possible shop primer defects and weld joints have to be blast cleaned and coated with a primer before the whole structure is painted. Iron oxide is also used as a pigment in some shop primers. These must not be overpainted with a zinc-rich paint. 

Uses Sole binder or with polyisocyanates, flexibilizer for anticorrosion primers, zinc-rich paints, can coatings Features Extremely fast drying exc. corrosion protection Properties Dens. = 1.06 g/cm (20 C) dynamic vise. 20,000-30,000 mPa-sj flash pt.= 40 C 48-52% NV... 

Uses Binder, antisettling agent for ready-to-use one-pack paints, zinc-rich paints used as primers or on their own (for corrosion protection on steel)... 

Preventd TP OC 3083 Preventd TP free-flow agent, zinc-rich paints... 

Electrochemical zinc-rich paints) automotive/transport 3 N... 

Sacrificial protection Sa-kr9- fi-sh9l pr9- tek-sh9n n. (1) The use of a metallic coating, such as a zinc-rich paint, to protect... 

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