New coating combines barrier benefits

GENERAL VACUUM Equipment (GVE) has recently developed and launched a vacuum coated clear barrier coating which, it claims, combines the benefits of the atmospheric clear barrier coating with the additional advantages of a vacuum coated barrier layer.

Vacuum coating requires only a small fraction of the thickness of the equivalent atmospheric coated layer to produce similar functionality. Typically, atmospheric coatings are measured in micrometres (10ˉ6m) and vacuum coated layers are measured in nanometres (10ˉ9m), with the barrier properties of the two structures being similar. This is potentially a huge environmental and economic advantage for vacuum coating technology.

General uses a standard aluminium metallizing machine as a foundation for this process and it is believed that two leading European converters have used their own similar systems for the past few years, successfully selling into markets worldwide.

GVE’s technology uses the controlled injection of oxygen into the aluminium vapour stream causing a reaction between the two elements to produce aluminium oxide (AlOx). This compound can be transparent if the process conditions are correct.

The pre-eminent feature of the GVE process is that a good water and oxygen barrier is achieved without the need for exotic and expensive vacuum ancillaries, such as plasma guns. The performance of the machine is based on a control loop that constantly monitors the optical properties of the coated substrate and also ties the injection of the oxygen in to the system and in to these properties.

Carefully examining and controlling these properties can guarantee both the oxygen and water vapour barrier properties across the width and length of the substrate. This tight control also permits very low usage of process consumables, enabling low cost production of a relatively high priced coating.

The AlOx coating system is only available in new General K4000 metallizers. The system will work together with the standard aluminium metallizer coating system but provides the converter with two technologies in one machine.

GVE has been running AlOx trials on such a machine for the last 12 months and it is now available for coating customers’ film whether PET, BOPP, CPP, PLA or other types of plastic film. Extensive barrier testing is also available on customers’ coated materials.

US start-up

General Vacuum Equipment has also been active on the sales front having delivered and started up earlier this year a new 2400mm wide special vacuum metalliser for Vacuum Depositing, Inc. (VDI) at its production facility in Louisville, Kentucky (USA).

The metalliser will be mainly used to produce reflective solar window film used extensively in the automotive and architectural glass industries. Window film is laminated to glass in order to reject solar energy and dramatically reduce ultraviolet transmission. Additional benefits of the laminated film include privacy, decorative appeal and greatly reduced glare.

The metalliser’s web handling design supports VDI’s vast array of products by providing exceptional control of various substrates under varying conditions.

VDI produces high value coatings to meet customers’ specific requirements for a diverse range of applications. These coatings can be produced in a variety of widths, utilizing various depositing techniques including thermal evaporation, sputtering and dielectric coatings on materials as diverse as PET, BOPP, PE, Polyamide, Aclar, Nylon and PEN.

In addition to solar control materials, the company also produces controlled density and opaque coatings for packaging, graphics and security applications, as well as sputtered metals and ceramics for aerospace, electronics, photovoltaic and other industrial uses.

GENERAL VACUUM:

T: +44 (0) 1234 852553
E: roger.astell@bobstgroup.com