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Stretch films essentially made from LLDPE, seem
to have established their place against shrink films, particularly
in the areas of large hoods to protect pallets. Simultaneously,
they have a strong presence in the segment for packaging of smaller
objects where protection through hand wrapping is carried out.
As commonly observed with many other applications,
the markets of North America and Europe have been well developed
for stretch wrap as compared to the other regions. One estimate
suggests that these two regions alone consume more than 1.5 million
tons - almost 70-75% of the total stretch film market in the world.
Besides they grow at almost 5-7% over these high consumption levels.
From a smaller base, the Asian region is expected to show higher
growth for stretch films.
The two major markets have taken up different approaches for developing
this business. The North American market uses general purpose conventional
C-4 (Butene) based LLDPE for raw material because of lower cost
and blends C6 (Hexene) to achieve better clarity and stretch retention.
On the other hand, the European producers tend to prefer C-8 (Octene)
based LLDPE to achieve better toughness, stretch retention and clarity.
The Europeans also tend to use lower density LLDPE or even Misallocate
PE grades.
The North American film producers generally use 5-layer cast film
extrusion to accommodate higher percentage of regrind material in
the core layers. These lines are equipped to have wider films (>2.5
meters) but run at a slower speed of about 200-250 meters/minute.
The European film converters tend to be more flexible by manufacturing
smaller width film (< 2 meters) but running at much higher speeds
(> 500 meters) on machines which can be used to produce the films
for other applications. Additionally there are some film converters
who utilize blown film lines compared to the exclusive usage of
cast film lines used in North America. The Europeans tend to use
3 layer co-extrusion systems for stretch films. The European film
producers however, use a complete automatic system to reduce dependence
on manpower and save costs.
While LLDPE is universally acceptable material of choice for stretch
film, Basell has developed the concept of utilizing Adflex (the
value added modified PP grade) in the core along with LDPE in the
top layers. Adflex, due to its better mechanical properties offers
better performance compared to LLDPE. This system is recently commercialized.
However, it is to be seen whether this new development will grab
a significant market share in the future.
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