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New Technology Stretch Films...Are They The Real Deal?

Welcome to another edition of the Inside Scoop. The purpose of the Inside Scoop is to provide you with
insights on the packaging industry from a semi-technical perspective that will help you in making good
bottom line decisions for your company. Each week we will explore another subject. This week we are
looking at New Technology Stretch Films, Are They The Real Deal?

Stretch film has been used in unitizing pallets since 1973 when Pat Lancaster of Lantech made the first
stretch machine. It has gone through a number of evolutions since then. The first major jump was when
LLDPE (Linear Low Density Polyethylene) resin was introduced during the late 70's. Dowlex® octene
copolymer LLDPE brought greater elongation together with greater puncture and tear resistance to stretch
film. Mobil X (remember the green film) was the first LLDPE stretch film introduced utilizing this high
performance resin. Before LLDPE, stretch films were pretty much limited to stretching no more than 30%.
With LLDPE we could get stretch levels up to 100% or more, and at thinner gauges. The 100% stretch level
was not a limitation of Dowlex® LLDPE itself, but the gel level in the resin. With the introduction of high
performance Unipol® gas phase hexene copolymer LLDPE resins, the gel level dropped dramatically and
stretch levels began to rise. Today nearly all LLDPE producers can produce high quality, high performance
stretch grade resins.

Stretch film pretty much developed within this arena until Metallocene catalyzed polyethylene resins
(mLLDPE) were introduced by ExxonMobil and Dow in the 90's. We found that mLLDPE resin yielded film
that was tougher, stronger, clearer, and that some grades had better adhesive properties than LLDPE. We
also learned that just blending it into the formula for stretch film did not improve the film other than to
give it better clarity. To have maximum impact on stretch film performance it has to be extruded in solid
layers and the higher the per cent mLLDPE, the better. The bottom line is that by using thick layers of
mLLDPE in stretch film produced on extruders with four or more layers, you can obtain a much stronger
film at thinner gauges. This is what we refer to as New Technology Stretch Film.

In the chart at the left, the New Technology stretch film is given
for each of the stretch film suppliers indicated. All of these
films have some things in common. They are designed to be able
to pre-stretch to 300% and more; and they are designed to

accomplish this using thinner gauges of film than would normally
be the case. What they do not all have in common is the ability to
perform at the same high levels of consistency while providing
enhanced load containment and overall performance.

file://C:\Documents and Settings\William Jackson\Local Settings\Temp\tmp44F.htm 9/30/2006