Pasted valve bag with a water-resistant surface of the outer ply to keep high tensile strength in a wet environment.
Standard paper bags for packaging cement and other powdery products are vulnerable to rain. To tackle the issue, Mondi, working in collaboration with major cement producer Lafarge, has developed an innovative rain-resistant bag particularly suitable for cement.
The wet-strengthened, machine-finished SPLASHBAG is designed to absorb less moisture than conventional bags. Its outer ply of Mondi Advantage Protect sack kraft paper has a water-resistant surface and is formulated to keep high tensile strength even in a wet environment. It also helps prevent moisture ingress if conditions are damp or humid during storage.
SPLASHBAG is a wet-strengthened, machine-finished bag designed to protect from liquid water (heavy rain) than conventional bags. SPLASHBAG has an outer ply made of Advantage Protect, one of Mondi’s popular machine-finished sack kraft papers. Advantage Protect sack kraft papers have a water-repellent surface and are formulated to have high tensile strength, to help prevent rupture. For example, the wet tensile strength of Advantage Protect in a grammage of 80 g/m2 is three times higher than that of standard sack kraft paper – an impressive figure.
SPLASHBAG's water-resistive properties are immediately apparent in side-by-side visual testing versus standard paper cement bags (test conditions simulating direct exposure to rain). Water gathers on the bag’s surface without being absorbed, then evaporates over a period of several minutes, leaving the bag essentially dry. By contrast, the standard bag absorbs the water, weakens as a result and may potentially rupture if exposed to extremely wet conditions.
Results of Cobb tests, which measure the amount of water absorbed into the surface by sized paper over a set period of time, indicate that the SPLASHBAG is resistant to rain for up to two hours.
If inadvertently left in damp rather than wet conditions, e.g. on damp sand, SPLASHBAG resists moisture ingress for up to 12 hours.
Importantly, none of these advantages comes at the expense of filling speeds or de-aeration rates, which match those of standard bags (in tests performed at Mondi’s Bag Application Centre in Austria).
SPLASHBAG is available as 25 kg and 35 kg bag and is particularly suitable for the construction industry but its properties can also be useful in other industries:
Pasted valve bags with a unique de-aeration system for high-speed filling of moisture-sensitive powders and building materials.
Pasted Valve Bags are closed bags made of high quality materials, designed for high-speed filling through a valve on spout packers; flexible closure options.
Pasted valve bag with a water-repellent outer ply for high-speed filling of moisture sensitive goods.