publisert 18.02.2005

SIG Corpoplast celebrates its jubilee

30 years of stretch blow technology from Hamburg

It all started with the beer. Impelled by the vision of replacing heavy and breakable glass bottles with lightweight and unbreakable bottles, the Hamburg based company Heidenreich & Harbeck developed the first high-performance blow machines for beer bottles made of plastic as early as the 1960's. Because the polyester material used later was not yet available in a blowable quality suitable for food applications, the first plastic beer bottles were composed of PVC.

Even the first high-performance machines featured tremendous productive efficiency: with a capacity of 200 bottles per mold, the total output already amounted to 10,000 bottles an hour.

After a patent had been applied for on the "Corpoplast process" in 1968, the company was taken over by the machine manufacturer Gildemeister in 1970. Shortly after that, a blowable PET (still an undisclosed "formula" at that time) with much better properties than PVC was launched by DuPont. Finally in 1975 Gildemeister transferred the new PET machine department to a new company that was named Gildemeister Corpoplast after the process of the machines. This was the foundation of today's SIG Corpoplast, which is thus considered as the inventor of modern stretch blow technology and is celebrating its thirtieth anniversary this year.

After its sale to the Krupp group in 1979, Corpoplast has belonged to the Swiss-based SIG group since 2000.

Altogether, the company from Hamburg has installed over 1,000 stretch blow machines at customers throughout the world. Many of the sturdy and reliable machines from the starting time of stretch blow technology are still in use. Now there have been many changes at an innovative company such as Corpoplast due to continuous advancement in 30 years. For instance, the output per cavity and hour was increased almost tenfold in this period. About 20% of all Corpoplast stretch blow machines were constructed during the past three years, that is in only 10% of the company history. And these 200 BLOMAX Series III machines make up approx. one third of the total output installed.

In the past 30 years SIG Corpoplast has learned a lot, changed a lot and achieved a lot. Today the company is operating more successfully than ever with an extensive range of innovative concepts and products. The newest stretch blow machine, the very compact BLOMAX 24 Series III with an output of 43,200 bottles an hour, was presented at the K'2004 trade fair in Düsseldorf, Germany in October. The PLASMAX coating system for applying a transparent, vitreous barrier layer to the inside of PET bottles has gone on line successfully at the first customers. And operators of older machines can take advantage of customized modernization concepts offered in a recently launched service campaign so that their Corpoplast machines are far from being ready for the scrap heap even after 30 years.