Oils are arranged in reverse order of lightfastness. This data is used to manufacture any alkyd paintwork materials. The exceptions are primers, for the manufacture of which tung oil and linseed oil are used. This is because the primer compounds are used as an intermediate layer that is not exposed to sunlight.
Alkyd compounds are used in combination with some other polycondensation, polymerization resins and cellulose nitrates. Such resins, depending on the modifying agent used, are subdivided into: alkyd-melamine, alkyd-urea, alkyd-epoxide, alkyd-styrene, uralkide, alkyd-polyorganosiloxane and alkyd-acrylic. They combine the properties of a modifying component and alkyd resin.
Alkyd resins are subdivided into: water-soluble (water-dilutable) and water-insoluble. And also on: diluted with organic solvents and soluble in them.
Nowadays waterborne (waterborne emulsion) paintwork materials have become the most widely used. They have undoubted advantages over paints and varnishes based on organic solvents, because they are not harmful to human body and are safe in terms of fire. Water-dilutable resins in interaction with amino-formaldehyde or phenol-formaldehyde water-soluble resins, which act as hardening agents, form a film.
Water-dilutable alkyd resins are used to make water-based enamels and primers. Glyphthalic resins diluted with organic solvents are used in production of fillers, primers and enamels for internal works. Pentaphthalic - for enamels and varnishes to be used in moderate climates, in the open air. Also drying alkyd resins are used for varnishes, lacquers, enamels, primers, hot and cold dried putties.
The following grades of unmodified alkyd-based varnishes and resins can be found at paint and varnish markets:
- Resins - VPFL-50, FC-135, FC-42, PGF-SIN-34;
- varnishes - PF-060H, PF-060B, PF-053H, PF-053B, GF-01, GF-019, GF-046, GF-072, B-Ep-0179 and others.
Pigments are highly dispersed colored powders. They are insoluble in water and film-forming agents. Pigments are mainly used for decorative purposes, to give color and luster to paints, primers and enamels. In addition to that pigments are characterized by different properties which influence the final product: lightfastness, chemical and weather resistance, wettability, dispersibility, oil resistance, hiding power, crystalline structure and ability to react with film-forming agents.
By their origin paint pigments can be divided into synthetic and natural, by their chemical composition - into organic and inorganic.
Inorganic pigments include titanium dioxide, zinc oxide, lithopone (gives white color), ochre (gives yellow color), iron lazuli, ultramarine (blue), iron minium, orange crown, mums (red), copper, chrome oxide (green color). As you can see - most inorganic pigments are salts of metals, oxides, hydroxides, which have a crystalline structure.
Among organic pigments we can distinguish phthalocyanines, anthraquinones, azopigments, diazopigments.
Some pigments can provide paintwork materials with additional useful properties. For example, if a paintwork is sufficiently filled with metallic pigments the coating becomes electrically conductive and thermally conductive. If the paint material is filled with zinc dust, it can be used as a protective primer.