Barrier Foil
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Barrier foil typically comprises of 3 ply of materials. One layer is usually made of polyester or non-woven polyester that provides strength at a wide variance of temperature and waterproofs the material. A second layer is an aluminium foil, available in a variety of microns, that is a barrier against water vapour transmission and gasses. The third ply is polythene that enables the foil to be heat-sealed. Heavy-duty grades of barrier foil often have a double layer of polythene for increased strength.
Barrier foils have a water vapour transmission rate of 0.05gm per m2 per 24 hours. This rate is 20 times lower than heavy duty 500 gauge polythene and 80 times lower than 125 gauge polythene. Barrier foils also provide excellent protection against damage from biological sources, ultraviolet light, acids, alkalis and odour transfer.
Barrier foils can also save on packaging costs. The quantity of desiccant required in a package is calculated according to BS 1133 Section 19 and since barrier foils have a water vapour transmission rate that is 20 - 80 times lower than commercially available polythene, a proportionally smaller mount of desiccant is required, depending on the thickness of the barrier foil’s polythene ply. Less desiccant can also mean lower freight costs. Barrier foils can also reduce the overall cost of a packing case because the case only needs to be protected physically and not climatically which means that the outer packaging specification can be reduced (i.e. lining papers can be dispensed with).
Rosewood stocks a comprehensive range of barrier foils. Each foil has specific characteristics such as thickness, weight, strength, water vapour transmission rate and temperature sealing ranges. Barrier foils should be fit-for-purpose because of the variance of their protective qualities. For example, certain products may require a thicker aluminium layer for reduced water vapour permeation.
There are several key factors to consider when selecting a barrier foil:
- The type of metal that requires protection from moisture.
- The shape of the product.
- The product’s weight and weight distribution.
- The duration for which protection is required.
- The destination.
- The mode of transport and whether the product will require periodic inspection.
Barrier Foil: Rosewood’s Specialist Options
Rosewood’s barrier foils can be supplied in rolls. Alternatively, bags can be supplied either customised or from a range of stock sizes. There are several styles of bag available depending on the application required and they include centre-seal box bags, lidded or loose-lid box bags, flat 2-dimensional bags and loose base box bags. Our barrier foil bags can include windows for humidity indicator cards.
Where our customers opt to make their own barrier foil bags, we can supply the foil. If bespoke bags are required, we recommend that a site visit be undertaken by a Rosewood sales adviser in order to view the product and the packing method in order to ensure that we produce the correct style, size and type of bag.
We also supply stock centre-seal box bags that are manufactured to suit some of our cardboard and plywood case ranges including our Euro cardboard packs and plywood cases. The range is manufactured from the standard commercial grade of barrier foil, BFR004.
- Highly effective barrier to prevent moisture ingress (up to 80 times greater than polythene).
- Highly effective odour barrier.
- Cost-effective packaging solution, due to the desiccant reduction required in comparison to a polythene based solution; this in-turn may lead to lower freight costs.
- Cost-effective packaging solution due to the option of outer package specification reduction.
