Sticky-Side Powder
Introduction
Sticky-side Powder™
is used to process the sticky-side of adhesive tapes and labels
for latent prints. As with any chemical process, we suggest
that you experiment on non-evidence items to become familiar
with this process before using it on evidence.
Excellent results:
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duct tape
adhesive bandages
paper-backed labels
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masking tape
plastic surgical tape
clear plastic tape
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packing labels
double-sided foam tape
reinforced packing tape
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Good to fair results
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cloth surgical tape
adhesive edge of 3M™ Post-it® notes
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frosted plastic tape
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Poor results
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black electrical tape (due to poor
contrast)
some paper labels and tapes and labels with dried-out
adhesives
some contact papers or shelf papers
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Safety
A dust mask is recommended
when measuring the powder to prevent inhalation of particles.
Once mixed, the material should not be ingested.
Mixing Instructions
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Method One
- Place approximately equal amounts
of water, Photo-Flo 200 and Sticky-side Powder™
into a small jar or beaker. It should be the consistency
of thin paint. More liquid or powder can be added to
make the mixture thicker or thinner as the need dictates.
Mix a total volume suitable for the application at hand.
- Use a small brush or camelhair
fingerprint brush to "paint" the liquid mixture onto
the adhesive side of the tape or label. This method
has also been found to work on the back side of some
tapes.
- Leave it on for 10 to 15 seconds
and then rinse it off with water. The tape can be rinsed
under running water, but the preferred method is to
gently agitate it in a bowl of water.
- When most of the solution is
rinsed off of the tape or label, examine it. Photograph
any developed latent prints.
- If the solution is left on too
long, it becomes difficult to rinse off. The solution
will adhere too strongly to some tapes and labels. The
solution may be applied but it must be rinsed immediately.
The other alternative is to use Meth od Two for these
types of tapes and labels.
Method Two
- An alternative method for processing
adhesive tapes and labels which are not suitable for
the painting process, is a soaking process. Add some
Sticky-side Powder™ to a bowl or tray of water.
The rinse water left over from Method One can be saved
and used for this method.
- Agitate the bowl of water to
stir up the Sticky-side Powder™ and submerge the
tape pieces or labels with the sticky side up.
- Allow the floating particles
of Sticky-side Powder™ to settle on the tape.
This process may take some time to develop the latent
prints. The resulting prints may also be rather faint.
Method Three
- Another variation is to add some
Sticky-side Powder™ to a bowl or tray of water
which can be closed. The rinse water left over from
Method One can be saved and used for this method.
- Agitate or shake the container
to stir up the Sticky-side Powder™ until a large
head of foam appears.
- Pass or draw the tape through
the foam only.
- Rinse the tape as usual.
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Kit Components
We offer a kit which contains
50 grams of Sticky-side Powder™, 473 ml (one pint) of
Photo-Flo, a camelhair brush, spoon, dropper bottle, mixing
jar, and instructions, all in a handy kit box.
Photography
Photography of latent prints
developed with Sticky-side Powder™ should not pose any
problems if the surface background is a light color. If the
surface is a dark color but will fluoresce, it may be beneficial
to use fluorescence examination to enhance the photographic
contrast.
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