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The Simultaneous Development of Latent Prints on
the Adhesive and Non-Adhesive Sides of Tape Using
a Rhodamine 6G in Tween 20 Solution after
Cyanoacrylate Fuming
Aldo Maldonado, BS Catherine G. Rushton, MSFS
Stephen C. King, BA Pamela Staton, PhDMarshall
University Forensic Science Center, 1401 Forensic
Science Drive, Huntington, WV 25701 West
Virginia State Police Forensic Laboratory, 725
Jefferson Road, South Charleston, WV 25309
Abstract Latent prints on the adhesive and
non-adhesive sides of tape must be processed
separately, which requires more time and
materials. This study proposes a way to process
latent prints on both sides of tape
simultaneously. Various tape types were fumed in
cyanoacrylate and dipped in an optimized solution
of rhodamine 6G, Tween 20, and water. They were
visualized with a green (500-525 nm) light and 1
orange-red (549 nm) filter. Prints were compared
to standard processing methods, and result in
comparison quality prints, yet requires less time
and fewer materials.
Results
Introduction Laboratories process a variety of
adhesive tapes for latent print evidence because
they are commonly used in the binding of victims,
weapon modification, and the manufacture of drug
packaging and explosives 1,2. However, common
powder methods are useless on adhesive surfaces
3. Instead, techniques such as the sublimation
of disperse dyes, gentian violet, TapeGlo,
Sticky-Side Powder, Wetwop, and similar powder
deposition methods are used. However, these
methods still require for both sides of the tape
to be processed separately, and these processes
often interfere with one another. They also
require more time, steps, and materials. This
study proposes a simple, faster, and more
universal method that can be used on different
types of tapes yet yield comparison-quality
prints.
Figure 2- Non-adhesive side ratings for Tween 20
and rhodamine 6G solution.
Figure 1- Adhesive side ratings for Tween 20 and
rhodamine 6G solution.
Table 2- Non-adhesive side ratings for Tween 20
and rhodamine 6G solution.
Table 1- Adhesive side ratings for Tween 20 and
rhodamine 6G solution.

• Materials and Methods
• Loctite "Hard Evidence" cyanoacrylate (Henkel
  Corp.)
• TapeGlo (Lightning Powder Co.)
• Wetwop (Lightning Powder Co.)
• Black powder (Lightning Powder Co.)
• Rhodamine 6G (Lightning Powder Co.)
• Tween 20 (Sigma-Aldrich Corp.)
• Original Duck Brand Duct Tape (ShurTech Brands)
• Original Duck Brand Packaging Tape (ShurTech
  Brands).
• Temflex Vinyl Electrical Tape 1700 (3M)
• Scotch Magic Tape 810 (3M)
• All tapes were photographed with a digital SLR
  camera. Tapes processed with TapeGlo or
  rhodamine 6G were illuminated with a green
  (500-525 nm) light source and photographed
  through a 1 orange-red (549 nm) long pass
  filter.
• Cut 15 cm strips of duct tape, and deposited
  fingerprints on both sides of tape.
• Fumed in cyanoacrylate for 5 min.
• Dipped in solutions of 0.2, 0.1, and 0.05 g/L
  rhodamine 6G in combination with 10, 20, and 30
  Tween 20 for 15 sec and rinsed in water.
• Applied same procedure to electrical, clear, and
  packaging tapes.
• To compare this method with a commonly used
  method, tapes were processed with TapeGlo,
  Wetwop, rhodamine 6G (0.05 g/L in water) and
  black powder. Manufacturer instructions were
  followed.
• Print quality was compared to a 3-point Likert
  scale

Tween 20
Tween 20
10 20 30
0.2 g/L 2.3 0.86 2.3 0.94 2.8 0.60
0.1 g/L 2.8 0.59 2.4 0.84 2.4 0.88
0.05 g/L 3.0 0.0 2.6 0.73 2.5 0.51
10 20 30
0.2 g/L 2.3 0.84 2.1 0.95 2.7 0.61
0.1 g/L 2.4 0.81 2.3 0.88 2.4 0.80
0.05 g/L 2.9 0.23 2.6 0.74 2.6 0.65
Rhodamine 6G
Rhodamine 6G
Table 3- Ratings for common methods and 10 Tween
20, 0.05 g/L Rhodamine 6G solution.
Adhesive Adhesive Non-Adhesive Non-Adhesive
Average Average
TapeGlo 2.6 0.57 Rhodamine 6G 2.9 0.31
Wetwop 3.0 0.0 Black Powder 2.4 0.62
Tween 20 2.9 0.23 Tween 20 3.0 0.0
Table 4- Results for Pearsons Chi-Square
calculations.
Adhesive Adhesive Non-Adhesive Non-Adhesive
?2 H0 ?2 H0
Tween20 61 6.7 x 10-12 Tween 20 72 2.3 x 10-14
TapeGlo 14 1.0 x 10-1 Rhodamine 6G 40 2.1 x 10-7
Wetwop 56 6.9 x 10-11 Black Powder 13 1.2 x 10-1
Figure 4- Tapes processed in 0.05 g/L rhodamine
6G, 10 Tween 20 solution. Clock-wise from
top-left duct tape, clear tape, electrical tape,
packing tape.
Figure 3- Ratings for common methods and 10
Tween 20, 0.05 g/L Rhodamine 6G solution.
Conclusions The solution of rhodamine 6G and
Tween 20 tested in these studies is a viable
option for the simultaneous processing of latent
prints on the adhesive and non-adhesive sides of
tape. It results in clear, identifiable prints
and it is comparable to standard methods of
processing, yet requires less time, fewer steps,
and fewer materials.

• Discussion
• Of solutions tested, 10 Tween 20, 0.05 g/L
  rhodamine 6G resulted in the highest rated, most
  consistent prints for both sides of tape (Figure
  1). Prints were rated 2.9 0.23 (adhesive), and
  3.0 0.0 (non-adhesive).
• Though Wetwop was rated higher than Tween 20 for
  the adhesive side (3.0 0.0) the difference was
  minimal. Both resulted in consistent,
  comparison-quality prints, and Tween 20 rated
  highest for the non-adhesive side.
• For the adhesive side, Tween 20 received ?2 61
  (H0 6.7 x 10-12 ) while Wetwop received ?2
  56 (H0 6.9 x 10-11 ). For the non-adhesive
  side, the Tween 20 method received ?2 72 (H0
  2.3 x 10-14).
• On electrical tape, transparent tape, and
  packaging tape (Figures 3-4), this method
  resulted in clear, comparison quality prints on
  both sides of the tapes.

References 1 Brzozowski, J., et al.
Visualization of fingerprints on sticky side of
adhesive tapes. Prob. For. Sci. 2005, 64,
333. 2 Schiemer, C., et al. Evaluation of
techniques for the detection and enhancement of
latent fingermarks on black electrical tape. J.
For. Ident. 2005, 55 (2), 214-238. 3 Ong, S.,
et al. Visualization of Latent Prints on Adhesive
Surfaces. J. For. Ident. 2004, 54 (2), 203-219.