Ultra-long-life coating

Citation

(2001), "Ultra-long-life coating", Anti-Corrosion Methods and Materials, Vol. 48 No. 5. https://doi.org/10.1108/acmm.2001.12848ead.005

Ultra-long-life coating

Ultra-long-life coating Keywords: International Protective Coatings, Coatings, Polymers

A new, heavy duty, high performance polysiloxane topcoat from International Protective Coatings – Interfine 979 – claims fewer coats and a superb quality finish which can reportedly be up to four times more durable on structural steel than standard polyurethanes.

Polysiloxanes, a product of inorganic polymer technology, are comparative newcomers to the heavy duty coatings industry. When used as part of the correct anti-corrosive system, polysiloxane coatings are believed to provide the best available long term resistance to corrosion on steel, even in the most extreme conditions.

According to IPC the secret of polysiloxanes' success is in the chemical bond that holds the atoms together. The resistance of this bond to the effects of nature and the environment, known as bond strength, is silicone based (inorganic), rather than carbon based (organic), as found in polyurethanes and epoxies.

Over time, the carbon-based chemical bond will break down under the effects of chemical exposure, sunlight, water and other environmental factors. This allows water to reach the steel substrate, which may cause corrosion.

The extreme toughness claimed of new Interfine 979 comes from its inorganic polysiloxane polymer network. To give it the additional benefits associated with organic polymers, such as flexibility, edge coverage and spray characteristics, a small quantity of organic polymer is added – in this case acrylic.

In practical terms, Interfine 979 is said to provide the mechanical properties associated with an epoxy midcoat (in a standard three-coat anti-corrosion coating system) while improving significantly on the cosmetic finish of a polyurethane topcoat, doing away with the need for an intermediate coat altogether. This saves time, and money, on corrosion protection.

Interfine 979 is stated to have Norsok Approval (Norsok M-501 System 1) one of the toughest standards employed in heavy duty coatings offshore today. It is said to perform equally well on offshore structures. bridges, stadia and other prestige projects. Generally applied over zinc rich epoxy primers, such as Interzinc 52, it can also be used for maintenance and touch-up work when used with suitable maintenance primers, such as Interseal 67OHS.

The new coating is stated to meet current VOC legislation too. It is also said to be HAPS free for use in the USA.

In addition it is the only polysiloxane finish on the market, says International, which can be supplied quickly in small quantities (as little as five litres) in almost any colour, a flexibility which professional coatings applicators will welcome.

The new intermediate/finish coating is being made available through IPC's Chromasean service. This. they state, offers fast, efficient colour matching from local distribution centres – typically only 48 hours for standard colours, 72 hours for others.

"The technology of polysiloxanes for finishes is comparatively new to the coatings industry. There are some on the market already, but we wanted to develop a product that we could guarantee would meet the high consistency standards we set for our global coatings range, wherever in the world it was ordered. This has involved exhaustive laboratory and field testing programmes and negotiations, to ensure consistency of supply, with material suppliers", explained IPC's marketing manager, Jim Kavanagh.

International Protective Coatings promotes the use of independent random infra-red fingerprinting on products being used in multi-national projects, in whichever country they are made. This effectively identifies chemically whether a product specified at the design stage of a project (and registered via fingerprinting) is the same as the product supplied at site, ensuring the customer is getting what he needs.

"Where products are made locally under licence, the brand owner cannot be sure that raw materials, details of manufacture and controls are consistent", Jim added. "With performance coatings it is essential that the product meets the agreed specification if it is to afford the protection it claims.

We manufacture all our products ourselves and welcome independent verification of their content".

Details from International Protective Coatings. Tel: +44 (0)171 479 6000; Fax: +44 (0)171 479 6555; E-mail: james.kavanagh@uk.akzonobel.com; Web site: www.international-pc.com.