1. What happens in
cold weather ?
At temperatures lower
than +15°C, adhesives evaporate much more slowly and so waiting times are
increased. The road is also more likely to be damp and this causes difficulties
with adhesion.
At temperatures lower than +10°C, the laminate becomes stiff
and difficult to manipulate and it can break. In addition, it does not conform
well onto the paving and may leave air pockets into which rainwater can run,
causing it to become detached.
2. Why is dampness
dangerous ?
Water is an enemy of
all adhesives and makes them totally useless.
If the relative humidity level
is very high when the strips are being laid, a film of water may condense on the
strip treated with adhesive, because of the local cooling effect caused by the
evaporation of the solvents, and this will prevent the glue from sticking.
If
the dampness is actually in the paving itself, the heat from the sun will cause
it to rise to the surface after the strip has been laid, and if it has no other
means of escape, it tends to detach the sheet from underneath. This can be
observed by putting a layer of transparent polyethylene on the ground and
sticking the edges down with adhesive tape. With the sun's warmth the inside
will steam up in a short while and this condensation is a result of the dampness
rising up from the paving.
3. What happens if
it is laid on top of a layer of paint ?
The most common
paints (e.g. Chlorinated rubber paint) dissolve in the usual solvents and this
also happens with the solvents contained in the DUSTFIXER and the PRIMER.
It
follows that, having been laid on a soft surface, the strip can then slip with
the movement of the traffic.
At other times the strip may adhere well on top
of the paint, but then this, over a period of time, separates from the paving,
taking with it the strip itself.
4. What if there
are oil or grease stains ?
Obviously oil and
grease are the enemies of adhesion. If they are not permanently removed the
strip will not adhere to those areas, and, with the movement of the traffic, it
will move, often taking with it other pieces nearby.
Particular attention
should be paid to places where buses and lorries are likely to stop and spill
drops of oil from the engine (e.g. at traffic lights).
5. What are the
effects of cracks or unevenness in the paving ?
Cracks are a source
of dampness coming up from underneath and frequently act as channels for
rainwater. Unless they are sealed completely, laying of the strips should not
continue in that vicinity in order to avoid increased possibilities of their
becoming detached in the future. The same thing happens with very uneven
surfaces: then, in addition to the problems with water, there is some difficulty
in making the material fit, and this can cause rips.
6. Why must the
road surface be thoroughly cleaned before laying the strips ?
Apart from the oil
and grease stains on the road and the dampness (see above), there are also small
stones and dust. The stones prevent perfect adhesion and form sharp points which
may pierce the strip, so allowing water to enter. Dust prevents adhesives from
working properly and makes them ineffective.7. Why must the adhesives
always be well shaken before use ?
Liquid adhesives are
made with rubber and resins dissolved in solvents: when standing they tend to
form a sediment, that is they solidify at the bottom. If they are not vigorously
shaken to mix them well, the first part used will be very liquid, made up almost
entirely of solvent without any adhesive capabilities, followed by a part that
is too thick, difficult to spread and which takes a very long time to
dry.
7. How close to
the edge of the pavement should they be placed?
It is advisable to
keep the strips at a distance of at least 0.5 m from the edge of the pavement
(e.g. at pedestrian crossings) for several reasons:
- this area is
usually dirty
- rainwater collects
there, sometimes forming puddles of stagnant water
- it is usually
impossible to press down the strips sufficiently well in such close proximity
to the kerb
8. What safety
measures should be taken?
Adhesives contain
harmful inflammable solvents and so, in general:
- do not use in
confined spaces
- wash hands before
eating or touching the face
- do not smoke or
light a flame near the containers of adhesive
- follow the
instructions on the label and refer to the safety data sheet
9. What
environmental safety precautions should be taken?
All products
containing solvents are harmful to the environment and so any excess product
remaining should never be dumped on the road or down drains, but should be
disposed of properly with special waste
10. How should
these products be stored?
In closed containers
away from extremes of temperature, in a cool well-ventilated place. The
effectiveness of the product must, in any case, be checked after 12 months from
the date of manufacture.
Sally Thermoplastic India Limited,
No.1, III rd Cross Street, First Main Road,
Kalaimagal Nagar, Ekkattuthangal,
Chennai- 600 097,India.
Phone : (91-044)- 22250475, 22254084
Fax : (91-044) -22250774
Mobile : 91- 0 - 9840060559
e-mail: mailto:info@sallythermoplastic.com