Sidel's ACTIS Coating Economical Barrier Option for PET Bottles

Sidel's newly invented proprietary coating process for PET bottles could be the breakthrough the beer industry is looking for as it attempts to venture into plastic packaging.

The new ACTIS — Amorphous Carbon Treatment on Internal Surface — process from Sidel (Octeville-sur-mer, France) provides vastly improved barrier properties over traditional, single-layer PET bottles. The plasma-coating technology reportedly increases oxygen barrier by 30 times over standard bottles. According to Sidel, ACTIS allows just 100 ppb oxygen penetration per month, which is well below brewers' standard of 1,000 ppb maximum per month. In addition, carbon dioxide barrier is said to be seven times stronger than single-layer PET. Sidel tests resulted in 6% CO₂ loss after six months, compared to market standards of 10% maximum in the same timeframe.

These properties make ACTIS-coated bottles comparable to glass containers and metal beverage cans, says Sidel, and the process is targeted for bottling beer, carbonated beverages and any oxygen-sensitive beverage.

Minutely Thin Coating
The process involves coating the inside of a standard, single-layer PET bottle with a layer of highly hydrogenated amorphous carbon, obtained from a food-safe gas in its plasma state. This coating, which utilizes just 3 milligrams of carbon to treat a 500 cc bottle, creates a minutely thin barrier — approximately 0.1 microns — inside the bottle. There is no co-injection used in the process, according to Sidel.

"There's no migration of the coating into the product. The coating is very stable," says Sidel's Nicolas Rivollet, who discussed the ACTIS process with Packaging Network at Interpack '99 in Düsseldorf, Germany, earlier this month.

The plasma treatment is done downstream from the PET blow-molding machine. It's performed by a patented machine whose design is based on Sidel's rotary, high-output rate technology. The premiere model, the ACTIS 20, features 20 stations and is capable of treating 10,000 PET bph for container sizes up to 0.6 liters.

Two years in the making, the ACTIS process has gained approval for food-safe quality from the Technische National Onderzoek, a standards organization accredited by the European Community. Sidel says the treated bottle is fully recyclable, as the amount of coating is just 1/10,000th of the total package weight.

A six-month taste test campaign that compared beer in both ACTIS-treated PET and glass bottles proved well for the ACTIS bottles. Two benchmark organizations, Jørgensen (Denmark) and Qualtech-IFBM (France), conducted the tests and concluded that the taste quality of beer packaged in both types of bottles is equal.

Cost-competitive to Glass, Cans
Sidel says it has managed to keep costs of the treatment to a minimum. "The technology is cost-competitive to glass and cans," says Rivollet. The company calculates that based on 33 cl and 50 cl size containers, the cost price of ACTIS-treated PET bottles is actually less than competitive packages.

Barrier material costs are kept low since performance levels are reached with just a tiny layer of coating and a very low consumption of precursor gas. Sidel estimates the cost of barrier material to be 1/60th of a cent per bottle.

As for operating costs, depreciation of the ACTIS 20 machine along with utilities are said to be 0.3 cents per bottle. According to Rivollet, the cost of the ACTIS 20 machine is one million Euros (US$1,062,500). A user would also have to pay an operating licensing fee.

ACTIS-coated bottles will be test marketed in France beginning June 15 by the DeGayant brewery (Douai, France) for its Amadeus brand. Rivollet says ACTIS 20 machines will be commercial by the end of this year.

For more information: Sidel, Octeville-sur-mer, France, Tel: +33 (0)2 32 85 86 87, Fax: +33 (0)2 32 85 81 00.