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23 Mar 2019

Non-Stick Coating for Stainless Steel Food Equipment: How ITC Bingo Stopped Seasoning Build-Up

Seasoning caking on bare stainless steel is a recurring cleaning job on a snack line. At ITC's Bingo plant, the stainless steel buckets of a multihead weigher were coated with Vetro Power Nano-Dynamis, a fluorine-free, food-safe non-stick coating for stainless steel based on polysilazane, which is superhydrophobic and oleophobic. The before and after photographs below show the result on a running line, and the rest of the post covers what the coating is, why it suits food equipment, and how it is applied.

Quick answer. A non-stick coating for stainless steel equipment is a transparent layer bonded to the metal so that oil and seasoning do not bond to it and can be cleaned off with a neutral cleaner. Vetro Power Nano-Dynamis is a ready-to-use, polysilazane-based non-stick coating for stainless steel and other metal surfaces. It is superhydrophobic and oleophobic, so oil and seasoning do not bond to the metal, it is food safe once cured (EC 1935/2004), heat resistant to 300 °C, fluorine-free, transparent, and rated to last up to 5 years. At ITC's Bingo snack plant it stopped seasoning caking on the stainless steel buckets of a multihead weigher.

Chemistry: polysilazane, fluorine-free, solvent-based, ready-to-use
Food contact: complies with EC 1935/2004 once cured
Temperature: -50 °C to over 300 °C
Cleaning: pH 3 to 12 cleaners; neutral cleaners generally sufficient
Coverage: roughly 800 to 1,000 ft² per litre (industrial, practical)
Service life: up to 5 years; reapply every 4 to 5 years
Cure: dry to touch in about 1 hour; fully effective after 5 to 7 days

The problem: seasoning sticking to bare stainless steel

On a snack line the seasoning is the product, and it is also the maintenance problem. At ITC's Bingo plant the multihead weigher that portions chips into packs is built from bare stainless steel. Every bucket, chute and hopper lip that chips slide over picks up seasoning, and it builds up as the line runs.

BEFORE

Bare stainless steel. Seasoning caked on the hopper lip (ring) and in the bucket corners, loose chips stuck to it.

Stainless steel weigher bucket coated with Vetro Power Nano-Dynamis, clean hopper lip while chips flow through the weigher

AFTER

Coated with Vetro Power Nano-Dynamis, line running. The same hopper lip (ring) and the bucket walls are clean.

The before photograph shows it clearly. The bare buckets carry a thick, caked layer of seasoning along the lip of the hopper and in the corners of every bucket, and loose chips stick to it. The ring marks the point where the build-up is heaviest, where product drops from the top cone into the bucket. Caked seasoning like this has to be cleaned off by hand.

The same happens elsewhere on the line. On an inclined conveyor at the same plant, the cleats carry a green and white residue of herb seasoning.

Herb seasoning residue on snack line conveyor cleats, a surface for a food safe non-stick coating — Seasoning residue on the cleats of an inclined conveyor at the same plant. The kind of surface a non-stick coating is meant for.

The result: a coated bucket on a running line

The after photograph is the same type of weigher bucket after coating with Vetro Power Nano-Dynamis. The ring marks the same hopper lip that was caked in the before photograph. It is bare, bright metal. Chips are flowing through the weigher above it, so this is a running line, not a freshly washed one. There is no seasoning film in the bucket corners and no loose chips stuck to the walls.

The coating is transparent, so the coated bucket looks like bare stainless steel. The difference is that the seasoning does not bond to it. The project record also files Vetro Power Nano-Dynamis under Teflon, food industry (ITC), alongside the weigher photographs.

	PTFE (Teflon)	Vetro Power Nano-Dynamis
Chemistry	Fluoropolymer (contains fluorine)	Polysilazane, fluorine-free
How it is applied	Baked on as a layer	Thin liquid coat, sprayed, cures at room temperature
Appearance		Transparent, stainless steel keeps its own look
Bond to metal		Bonds chemically to the substrate

What a non-stick coating for stainless steel does on the metal

Superhydrophobic

Oleophobic

Easy-to-clean

Food safe once cured

Heat resistant to 300 °C

Fluorine-free

Transparent, no change in look

Lasts up to 5 years

Vetro Power Nano-Dynamis is a clear, ready-to-use coating based on polysilazane technology. It forms a barrier layer that bonds chemically with the substrate and cures at room temperature with atmospheric humidity. Once cured the surface is superhydrophobic and oleophobic, so water and oil do not wet it, and the protected surface can be cleaned repeatedly without reapplying the product. The coating is neither matt nor gloss. It is invisible after application, so the stainless steel looks exactly as it did before.

Why it suits a food plant

Food contact. Once the product has cured it complies with the requirements under the European Framework Regulation (EC) 1935/2004 relating to Food Contact Materials. It is also fluorine-free, so it is not a PTFE or fluoropolymer non-stick system.

Heat. The coating tolerates -50 °C to over 300 °C and is heat resistant up to 300 °C.

Cleaning. Coated surfaces are cleaned with cleaners in the pH 3 to 12 range. Strong mineral acids and alkalis should be avoided and are unnecessary, because neutral cleaners are generally sufficient to clean coated surfaces.

Durability. The coating is UV resistant and, once fully cured over 5 to 7 days, forms a very strong bond with the substrate. It does not discolour, crack or peel. Chemical cleaners or acid will not remove it. Reapplication is recommended every 4 to 5 years.

Specifications

Base	Polysilazane, solvent-based, ready-to-use
Substrates	Stainless steel, aluminium, zinc, copper, brass, bronze and other smooth, non-absorbent surfaces
Food contact	Complies with EC 1935/2004 once cured
Temperature range	-50 °C to over 300 °C
Corrosion test	Salt spray in accordance with ASTM B117
Density	approx. 0.92 g/cm³
Flash point	below 21 °C
Coverage	roughly 800 to 1,000 ft² per litre (industrial, practical)
Service life	up to 5 years; reapply every 4 to 5 years
Shelf life	12 months from delivery date, at 20 °C
Packaging	1 L, 5 L, 20 L, 200 L

How the non-stick coating is sprayed and cured on food equipment

Strip, degrease and dry. The substrate must be clean, grease-free and absolutely dry. Cavities and drainage channels are dried with absorbent cloths or blown dry with compressed air. On a damp surface the coating reacts prematurely and cannot form a permanent seal.

Check the conditions. Substrate temperature 5 °C to 30 °C, relative humidity 30 to 80 percent, no direct sunlight. For plain metal surfaces, application under clean-room conditions is strongly recommended. Test on a small area first.

Spray. HVLP spray is recommended (around 2 to 3 bar, 0.8 to 1.3 mm nozzle). Microfibre applicators or microfibre-flocked rollers also work. Mistakes can be corrected within about 10 minutes; after that the repellent surface will not take a second coat. Applied by trained personnel only.

Cure. Dry to touch after about one hour. Water resistant after 8 to 12 hours at room temperature, 2 hours at 80 °C, or 1 hour at 130 to 180 °C. Fully effective after 5 to 7 days at room temperature. On stainless steel, curing above 80 °C is recommended for optimum adhesion.

Good to know. Vetro Power Nano-Dynamis is a solvent-based product and is applied by trained personnel following its safety data sheet. It cannot normally be painted over, and it is not easy to remove: sanding or light grinding is the recommended route if removal is ever needed. Coating needs the equipment stopped, stripped and degreased first.

Where else it applies

The ITC Bingo weigher is one stainless steel surface in a plant full of them. The product data lists the same coating for tank equipment and industrial plant, inside and outside, ventilating systems, industrial plant and equipment, and any metal surface exposed to water vapour. It is also suited to smooth, non-absorbent surfaces around the metal: polyurethane and epoxy paint systems, polyester paints and GRP. For fingerprint and smudge control rather than release, see the related post on anti-fingerprint coating for stainless steel, and the full metal coatings range.

If you run a food line and are cleaning seasoning or product off stainless steel by hand, the quickest way to find out whether this works for you is a test coat on one bucket or one chute.

Vetro Power Nano-Dynamis

Food-safe, non-stick polysilazane nanocoating for stainless steel and metal equipment.

View the product Request a trial

Frequently asked questions

Is Vetro Power Nano-Dynamis a food-safe non-stick coating for stainless steel?

Yes. Once the product has cured it complies with the requirements under the European Framework Regulation (EC) 1935/2004 relating to Food Contact Materials. It is fluorine-free.

How is it different from a PTFE (Teflon) non-stick coating?

PTFE is a fluoropolymer. Vetro Power Nano-Dynamis is a fluorine-free polysilazane coating that bonds chemically to the metal and stays transparent, so the stainless steel keeps its own appearance. It is applied as a thin liquid coat and cured, rather than baked on as a layer.

Is it a high temperature non-stick coating?

The coating tolerates -50 °C to over 300 °C and is heat resistant up to 300 °C.

How do you clean coated equipment?

With cleaners in the pH 3 to 12 range. Neutral cleaners are generally sufficient. Strong mineral acids or alkalis should be avoided. The surface can be cleaned repeatedly without reapplying the product.

How long does the non-stick effect last?

The coating is engineered to remain effective for up to 5 years. For optimal protection, reapplication is recommended every 4 to 5 years.

Can it be applied on site?

Yes, by trained personnel. The metal must be clean, grease-free and absolutely dry, at 5 to 30 °C and 30 to 80 percent relative humidity. For plain metal surfaces, clean-room conditions are strongly recommended, and curing above 80 °C gives the best adhesion on stainless steel.