Intercept® products are made from a thin ‘reactive polymer’ barrier film made from copper that is chemically bonded to a polymer (typically polyethylene). It works by intercepting and neutralising reactive gases that permeate the film.
Reactive gases like nitrous oxides (NOx), ozone (O3), hydrogen sulphide (H2S), sulphur dioxide (SO2), carbonyl sulphide (COS) and hydrogen chloride (HCl), even in trace quantities, and particularly in the presence of moisture and ultraviolet light, are implicated in the degradation of most materials, including metals, plastics, rubbers, fabrics, paper, paints, ceramics, leather and magnetic media. Apart from acting as an effective barrier against reactive gases, Intercept® films also have about half the moisture vapour permeability of clear polyethylene sheet of the same thickness. Additionally, the antibacterial, antiviral and anti-fungal properties of copper, well-recognised since antiquity, act to inhibit bio-deterioration due to these microorganisms.
Intercept® films contain no volatile or abrasive additives and fillers, and pass the Photographic Activity Test and other archival criteria.
Intercept® products are currently being used by museums and galleries worldwide for wrapping and packaging objects for storage and transport; as backing for artwork (to intercept contaminants emanating from walls); for lining display and storage cases; for storage and preservation of fabrics, metallic threaded garments, coins and medals; and for long term storage of CDs and electronic media.
A feature of bags and enclosures made from Intercept® films is that they not only intercept reactive gases in the external environment, but also effectively scavenge and cleanse the internal microenvironments of reactive contaminants trapped or released (out-gassed) by the objects enclosed. The films also have an ‘in-built’ visual indication that signals it is working: When both sides of the film have turned a dark grey or white, the film has been effectively consumed and should be replaced. Intercept films may be expected to remain effective for more than ten years in typical indoor environments, and for three to seven years in more aggressive industrial or exposed situations.
More accurately, a copper metal-oxide-semiconductor (MOS) covalently bonded to the polymer. In its usual form, the film is a lamination of three layers that are extruded and fused together without an adhesive: a polyethylene core layer, providing the strength and half the thickness of the sheet, sandwiched between two Intercept layers.↩