Market possibilities for the patented technology

Non-sack niches: lumber wrap, roof underlayment, builders’ film:

A roughened film or woven fabric surface may be much safer to walk on, be it dusty or wet or icy or frosty: it may provide enhanced walking safety. If also its other side is roughened, it may slip less, on the surface (e.g., lumber, board etc.) on which it is applied. Self-grip-style roughened web surfaces can be surprisingly safe to walk on.

Bagging of “difficult-to-palletise” filling goods:

Some bulk products are known to be problematic when it comes to their bagging and stacking. Their packages will shift, pallet loads deform, during storage and transport. Several critical parameters of the filling goods may be held responsible for the problems, but a suitable anti-slip feature of the sacks may handle them all.

    Slipperiness of the packages’ outer surface due to the contents:

    • Slip grade polymers or masterbatches packed, of the migrating type
    • Oily, greasy filling goods puffing out (e.g., fat powder, soy powder, premixes, feed, etc.)
    • Wet packages (e.g., chilled goods)
      » Special case: to be stored outdoors, in rain (e.g., cement, cement mixes, sand, gravel, aggregates, soils, etc.)
    • Frozen packages covered in white frost (e.g., frozen food)
    • Spherical-powdery filling goods puffing out (e.g., certain sands, cement mixes, certain salts, S-PVC, etc.)

    Frozen vegetables in fleece-grip sacks, covered in white frost, to be transported without pallet film. With the permission of Foltrade kft.

    Deformation of the packages due to the contents:

    • Easy rearrangement/flow of goods within the package (e.g., certain salts, certain grains, certain minerals like quartz sand, blast abrasives, glass beads, slip grade polymers, hard spherical aggregates or pellets or beads, aerated goods like fine powders in film sacks etc.)
    • Compacting of goods within the package (e.g., potting soil, peat, fuel pellets, aerated goods like fine powders in film sacks etc.)
    • Hot fill, causing creep of bag wall

    Frozen vegetables in fleece-grip sacks, covered in white frost, to be transported without pallet film. With the permission of Foltrade kft.

    Super-easy-flowing quartz sand in fleece-grip sacks, to be transported without pallet film. With the permission of Foltrade kft.

    Other problematic goods

    • Extremely lightweight packages (e.g., expanded perlite)
    • Hazardous goods, for example under ADR (e.g., fertiliser)
    • All goods that need to be transported long distances and/or intermodally
    • All goods that are currently packed/palletised with any traditional so-called anti-slip feature,
      be it sack film with mixed-in additives, embossed sack film and/or palletising glue.

    Extreme-lightweight expanded perlite in fleece-grip sacks, to be transported without pallet film. With the permission of Foltrade kft.

    Advantages over competitor anti-slip technologies:

    Traditional embossing, of films, should work as based on protrusion-with-protrusion interaction. Its limited success, especially its limited dynamic coefficient of friction, is believed to be caused by the fact that embossed protrusions are not undercut. More over, they are hollow and may fade away by time. Further: not all packaging webs can be embossed, at all. On the other hand, however, the patented, technically universally applicable, undercut self-grip-style anti-slip protrusions are solid and may provide robust mechanical interlock resulting in high static as well as dynamic coefficient-of-friction values, even after multiple repeated slides.

    Anti-slip additives (e.g., HMWPE, ceramics), mixed into the outer layer of a coextruded film structure (if they are allowed in the product at all), are, again, usually not undercut enough for a really effective mechanical interlock.

    High-coefficient-of-friction inks, or covering lacquers, may lose effectiveness as soon as surficial moisture or any dust comes into the picture. The patented technology, however, involves three-dimensional surface features, anti-slip micro-protrusions, which may appear to better overcome surficial contaminations, be it GripTop®, self-grip or fleece-grip.

    Water-based palletising glue’s one drawback is that it may not be applied well enough onto any dusty (or wet or icy) or locally-non-flat package surfaces. Another drawback is that it needs time to solidify, therefore the fresh pallet loads must wait for a long time (protected from freezing) before they can be moved. In addition, probably neither the packers nor the consumers like it. But, more importantly, palletising glue also has another, not so evident drawback, namely that once it is popped up, it never sticks back again. Why it is a problem? The following video will help understand.

    Certain palletised unit load patterns may be sensitive to a horizontal swinging of the load during a truck delivery (and this is not necessarily about braking, but also about an inevitable continuous left-right swinging). It means that in such pallet loads a realistic horizontal swinging of the load is transformed into local vertical separation events between adjacent packages lying on one another, originally glued to one another, in the middle of the stack. After such a separation, those two packages that separated, or popped up, from each other for a moment, will now be free to start to shift, horizontally, away from each other in response to the continuing vibration (unless they are anti-slip packages). If a glued pallet load happens, just once, to be shaken enough to suffer such hidden, internal separation events, its hours are numbered, because it will then behave as if there were no glue fixation between those once-separated packages. In our understanding, an example of such kind of a vibration-sensitive stack pattern is that commonly used for packing commodity polymer products, like polyethylene or polypropylene: (11 layers) x (5 packages/layer) x (25 kg/package). This hidden glue-pop-up phenomenon is believed to stand in the background of trucks too often arriving with deformed, “paunchy” unit loads of plastic pellets originally nicely palletised with palletising glue. Anti-slip sack packages, however, may help preserve the load integrity of these commodity polymer pallet loads.

    Testing of a traditional glued stack of commodity polymer. The palletising glue proves vulnerable. NOT antislip sacks.

    SAVE MONEY:

    • Downgauge + increase recycled-content in sack films
    • Use thinner/cheaper pallet film, or leave it entirely

    Today’s FFS film experts talk about downgauging and increased recycled-content. This is where the patented anti-slip feature is believed to potentially add great value.
    A general, commodity palletised unit load (e.g., of fertiliser or polymer etc.) must survive storage and transport without getting too much deformed. One important source of the feared pallet load deformation is when adjacent packages start to slip relative to each other, in the stack. That slipping displacement may be caused by the fact that the individual shapes of the packages unwantedly change, by time. To avoid that, packers seek to use sacks of a good-enough shape retention. Shape retention of a heavy-duty shipping sack is known to be primarily determined by its film’s stiffness and creep resistance. (Creep means the irreversible elongation the film suffers by longer time.) So, packers use (especially in the summer heat) thick-walled and expensive film sacks so as to provide sufficiently high stiffness and creep resistance, so as to provide sufficient package shape retention, all in order to prevent adjacent packages from any slipping displacement.
    It can well be the case, that the bottleneck preventing any current given traditional sack design from being further downgauged is its critical creep resistance (see the use of thicker FFS films in the summer). In addition, today’s regulations drive the industry towards using higher and higher recycled content in the FFS sack film whose weakest point will potentially be creep resistance. Namely, in designing a sack with increased recycled content, drop-test-resistance and toughness on the one hand and creep resistance on the other hand may be difficult to achieve simultaneously. However, if the packages are anti-slip enough, then they will expectedly not slip relative to each other, even if they get expressly deformed, which could be called creep-insensitivity. That may make it possible for the packer to use thinner bags of lower-quality blends, even though they creep. Savings therefrom might well compensate for extra costs of the anti-slip feature.

    The same holds for pallet covers (e.g., stretch hoods and stretch wrap) as well. With an effective anti-slip sack design used, one may afford to use thinner and/or cheaper pallet cover, or even: no pallet cover at all (depending on unit load dimensions and other requirements).

    As an illustration, see the following real-life example, with fleece-grip bags:

    • Packed product: wet moorland peat, a compressible soil-like product, rich in fibre, and of varying density due to varying moisture content, problematic to palletise in ordinary plastic sacks in any stable way.
    • The product is sold by the volume (e.g., 50 l per package).
    • Package mass: varying between 25 and 35 kg per package, depending on actual water content.
    • The outer surface of the packages is often wet, from the wet (sometimes: soaked) filling product as well as from the outdoor storage without pallet covering.
    • Packaging film: fleece-grip anti-slip FFS PE film tube, thickness 120 microns.
    • Film composition: monolayer-extruded, 100% recycled PE (70% mixed recycled PE + 30% recycled stretch-film), in fact pretty bad stiffness and creep resistance, bag walls even wrinkled.
    • Pallet covering, for storage and truck delivery: none.
    • Customer satisfaction: 100%.

    Wet peat in fleece-grip sacks, transported without pallet film. With the permission of Foltrade kft.

    SAVE MONEY: source reduction through package- and stack redesign:

    Package designers seek to minimise the sack film surface (m2) consumed for packing up a given unit-volume (dm3) of fill goods. From that perspective, using cubic-shaped packages would always be the most economical, minimising the mentioned ”m2/dm3” ratio. Cubic-shaped packages, however, would, with most bulk solids in real life, be far too tall to remain stable in a pallet load. Also, a square-shaped top view of the package does not provide good possibilities for any brick-bond palletising patterns. Namely, a stable palletising pattern, traditionally, typically needs a greater or smaller overlap, brick bond, between adjacent packages lying on one another, which, however, necessitates such package dimensions whose length, in top view, is greater than its width, in top view. In practice, the greater sacrifice is made in order of load-stability, the farther the selected package geometry is from the ideal cubic shape. Fairly source-optimised package and pallet-load designs (for example those typically used for commodity polymers packaging) may introduce load stability problems (which, however, might be handled with anti-slip packages!), while, on the other hand, providing increased pallet load stability may introduce extra material costs due to using elongated and flat packages put in safe brick bonds on the pallet (for example as is typical with traditional potting soil packaging). Introducing anti-slip packages based on the patented technology might provide sufficient pallet load stability with simultaneous savings on sack film, due to using taller and/or less elongated packages. Savings therefrom might compensate for extra costs of the anti-slip feature.