Red Oxide
Red Oxide is a specific paint developed as a finish coat originally for the farming community to utilise a fully nontoxic palette of raw materials chosen for their environmental credentials. The key resin used to formulate these products is derived from soya been oil and for the best agricultural oxides reacted on with glycerine rather than a chemical polyol as the esterifying alcohol.
Combined these can account for up to 85% of the basic resin system and as all are crop based a good basis for sound renewable resource policy for any agricultural community.
It is also no surprise, to find that due to these environmentally friendly credentials this type of finish has also lately become popular with those wishing to live up to those high environmental goals and whose seek to replace as many petrochemicals in their products as possible with those from renewable resources.
However, it would be incomplete to comment on Agricultural Oxide and its environmental credentials without giving at least a passing look at how the product got its name and why. The primary pigment in Red Oxide Primer and Red Oxide Paint is Red Iron Oxide. In the early days this was a simple rock derived pigment chosen for its low toxicity, high colour strength, hiding power and light fastness. The light fastness was particularly important for the agricultural oxide as often pieces of equipment would be put together or buildings needed patching in and colour drift overtime had to be avoided as much as possible without reverting to expensive colour matching techniques. This also helped the agricultural industry to be efficient in protecting its assets and gave them the opportunity to mix and match from a variety of suppliers.
In later years this “natural” iron oxide tended to be replaced with a synthetic iron oxide which provided a much more defined colour and in some cases a limited range of colours became possible although in most cases the reference to red oxide is still a reference back to its original roots as a natural pigment and many purist still insist on this characteristic.
Red Oxide finish paints have, as previously mentioned, also been taken up in other market sectors where environmental credentials are critical and applicators were asked to look for those high levels of renewables in the product for their metal paint and for applications where the specifier wished to clearly demonstrate that they had gone the extra mile. In general a good quality Red Oxide Primer is always the same red brown colour, which typifies the product although the same “type” of paint can now also be offered in a limited range of what are known as “earth colours” but still based on iron oxide and colours can generally be made to order now as anything from terracotta (almost orange) to a “bulls blood” deep red. The identification of these is often from
the original colour reference to the iron oxide used so it is often found that whilst most agricultural oxide is referred to as “130” a “110” or a “180” can be offered too but prices tend to be much higher due to these modifications. The colour reference in general can be interpreted as the higher the number the more the colour has” shifted” from orange terracotta “110” in increasing blue tone through the more usual “130” to the “bulls’ blood” 180.
These alternative shades of Agricultural oxide are usually special request colours and hence the higher cost but are of interest to those wanted that “environmentally friendly” label and good durability and light fastness combined with good opacity.
Traditionally, Red Oxides were applied over a zinc phosphate primer, on metal or machinery. However, as people looked for safer alternatives with better environmental and safety credentials these zinc derived primers which are all environmentally hazardous have been replaced by nontoxic versions providing good corrosion protection without the environmental hazard. Nanoguard ACP is one of the leading technologies in this market place although there are others including Novinox PC01.
In conclusion for a good, long lasting and environmentally sound finish coat for your painting project, red oxide is a safe bet. The limited colour option can be a challenge but for most people in the agricultural industry this is seen as a benefit. For other designers and applicators, the rustic palette reminiscent of Tuscany and medieval Spain also has its charms and forms an essential part of the designer’s toolbox as well as the practical farmer wanting to keep his establishment safe, clean and well maintained.
Whilst it is rare to find designers and farmers in the same store, they now have a good environmentally friendly coating in common – Red Oxide!