more material is required to achieve a mechanically-re-
sistant container. Production cost also increases due to
higher tooling costs and slower line speed.
3.
Plastic has better corrosion-resistance than metal.
However, permeation is a non-starter in many cases. UV
rays can compromise the mechanical and chemical integ-
rity of the container. Sometimes material blends are re-
quired, which involve higher costs than the round
PET-bottle benchmark and are even higher than metal
cans.
4.
Enhanced decoration options:
As plastic containers
can be transparent, the appearance and decoration op-
tions are enhanced. However, the prescribed filling levels
of less than 75% for the sake of safety, not to exceed 90%
filling level at 50°C, may cause consumers to question the
low visible filling level, see photo.
Resistance of plastics
Resistance against propellants is one of the most impor-
tant limiting factors when developing of plastic aerosol
packs. PET works best with the propellant isobutane,
which has a lower pressure than the commonly-used pro-
pane/butane blends; PET does not work with dimethyl
ether (DME), which penetrates the PET wall, compromis-
ing the mechanical stability and safety of the product.
PE/PP would work with DME, but the mechanical resist-
ance of these materials is questionable.
Plastics work with compressed gases, but permeation
rates can be high. Sometimes plastic needs a special
pre-treatment, a thicker container wall or an additional
protective layer.
The resistance against ingredients varies, especially when
there are perfume components, which are small mole-
cules that can easily penetrate and weaken the mechani-
cal stability of the container.
Ozone resistance is less of a risk. However, ozone can
lead to plastic deterioration over a long period of time, so
containers should protect against it, the same way rubber
tyres are protected with the help of wax coatings.
It is assumed that aerosols are fully functional even years
later. Metal cans easily remain fully functional for dec-
ades.
Resistance against UV rays is an issue. After all, every
time plastic is exposed to daylight, UV rays irreversibly
damage parts of the can at a molecular level. PET in par-
ticular is not UV-resistant and possibly requires long-term
protection.
Another aspect that needs to be considered is resistance
against bacteria and other bugs, which has both positive
and negative aspects.
Recent research revealed that the bacterium Ideonella
sakaiensis are capable of breaking down PET (reported in
2016) in landfills. This is great news on the waste-dispos-
al front, but not great news for product safety before-
hand. This shows how unexpectedly nature can react to
artificial materials.
There are similar findings concerning other plastics. Ny-
lon serves as nourishment for Flavobacterium (reported
PACKAGING
Your Innovation Partner
NEO Spray
is the specialist for deodorants and
all kinds of personal care and household products.
And
NEO Spray
is a member of the successful NEO
family with its unique design.
It is suitable for LINDAL’s standard male and
female valves and the fingerpad can be customized.
For more information please refer to:
Tony Harman
+49 38828 231153
LINDAL Group, the global
manufacturer of valves,
actuators and dispensing
systems for aerosol
products.
NEO SPRAY
TEAM
SPRAYER
