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THE GLOBAL FLEXIBLE PACKAGING
MARKET, NOW AND 2015 , PIRA, BRUSSELS 2005
PIRA, Brussels 2005 Flexible Packaging 2005
PIRA 5th International Conference
19th-20th October 2005, Brussels Belgium
Plastics are a miracle and plastics films are an even greater miracle.
Plastics have been a success story, for their unique features. Plastics
truly are “miracle materials”, with the almost infinite
combinations of various molecules creating these multiple polymers,
in the true heart of matter.
Why the success of plastics in packaging, and everywhere?
Plastics have many properties, often equivalent, or inferior, to
those of traditional packaging materials, but the combination of
these average properties generally gives a unique synergy, their
very value for many applications. One of the most striking features
of plastics is to be, at the same time, flexible glass and transparent
metal.
Plastics are light, generally lighter than other packaging materials.
Even when they are heavier, than wood, paper or board, their higher
mechanical strength allows using less plastic. Plastics are generally
less bulky than the materials they replaced, film versus paper and
board, plastic bottles versus glass bottles.
The miracle of plastics films in packaging is like an "invisible
bubble”, thin and light. The most extraordinary package probably
is the 300 grams of stretch film, putting together a pallet of hundreds
of kilos and costing less than 2 dollars.
Plastics are the ideal ecological package.
Plastics can be made into a great variety of package shapes, by
their main processes, bottle blow molding, extrusion of film and
sheet, thermoforming of thin wall containers, molding of containers
and closures, and many other processes of lesser quantitative importance.
Most plastics are good barriers to water and moisture, an obvious
advantage over paper and board that have to be treated. Barrier
plastics, materials and processes permit to greatly improve the oxygen,
gas and flavor barrier of the plastics they are associated with,
however never achieving the complete barrier provided by heavier
glass and metal.
Plastics can be most easily associated with traditional materials,
boosting the overall performances to fit almost all packaging needs.
The major trend is the final replacement of traditional materials,
up to aluminum, steel (in closures and in cans), and glass, by the
irresistible push of plastics. More and more, plastics are
becoming the one and only packaging material.
Film definitions
There often are long, and pointless, discussions about the various
definitions contained in the terms of “films” versus “sheet”,
and the not completely consistent dividing lines between flexible,
semi rigid, or semi flexible, and rigid.
In common use, films are planar forms of plastics that may be thick
enough to be self-supporting, but thin enough to be flexed, folded
or creased without cracking.
The dividing line between film and sheet is sometimes given as:
- 2 to 200 µm, flexible
- 200 to 400 µm, semi rigid, or semi flexible
- Over 400 µm, rigid.
However, in practice, a number of flexible materials are just in-between,
like PA, nylon, and PVC. It is increasingly admitted that most thermoformed
containers, at least the shallow trays, are in the flexible category.
The thickness criterion defines films as of 250 µm, or 0.25
mm, or 10 mils (of an inch), or less, down to 2-4 µm. Sometimes
the film definition goes up to 300 µm, or 0.30 mm, or 12 mils.
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