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Chemical Name:
Surface Used On:
Dark-colored tapes, adhesive & non-adhesive surfaces.
Sensitive To:
Cyanoacrylate deposit.
Development Color: Method to Record: Hazard: Protective Clothing: Fume Hood Use:

Yellow fluorescent

Yellow or 2A filter

Eye Damage

U.V. - Eye Protection

Reagent Characteristics

Development Complete When:

Source of Error:



Storage Container:



Similar Reagents

Sequential Reagents
(Not necessarily in this order.)

Abridged Reagent Sequence

Visual Examination
Forensic Light
Cyanoacrylate fuming
*** Liqui-Drox ***
Ultra-violet lamp
Forensic Light

200 ml Ardrox P-133D
400 ml Liqui-Nox
400 ml distilled water
Combine and stir the chemicals thoroughly. 
A thick milky-yellow solution should result.
1. Using a camel hair brush, apply 
the reagent onto both sides of the tape 
until a lather is produced.
2. Wait approximately 10 seconds. 
3. Rinse under a gentle stream
of running cold tap water.
4. Allow the tape to air dry.
5. View under a Forensic Light 
Source or Ultra-Violet lamp able to 
produce a long-wave ultra-violet 
light output.

Use ultra-violet protection,
yellow or orange colored goggles.
6. Photograph results using 
an ultra-violet blocking 2A filter.

Ridge Detail Visualized by:

Ultra-violet light induced.

Reagent Applicabilities:

Non-Porous surfaces
Tape technique

Other Chemical Name(s):


Working Solution Shelf-life:

Six (6) months.

Process Summary:

Effective for dark-colored adhesive tapes, the Liqui-Drox method is a post-cyanoacrylate process involving brushing the reagent unto tape, rinsing, then viewing the result under long-wave ultra-violet light. This reagent is composed of a mixture of a fluorescent agent, a detergent and water.

Accepted Deviations:

Supporting Reference Materials:

1. Minutiae Magazine, Summer Special 1994, Issue No. 24, pg.7.

2. "Chemical Formulas and Processing Guide for Developing Latent Prints", U.S. Dept. of Justice, pg. 47-48, 1994.

3. Hollars, M., Trozzi, T., and Barron, B., "Development of Latent Fingerprints on Dark Colored Sticky Surfaces Using Liqui-Drox", Jor. Forensic Identification, Vol. 50, No. 4, July/Aug 2000, pp. 357-362.

4. Rees, A. and Schwartz, R., "The Effectiveness of Liqui-Drox and a Comparison to Other Adhesive-Side Processes on a Variety of Tapes, For. Sci. Comm., vol. 5, no. 1, 2003.

5. Schiemer,C., Maynard, P., Roux, C. and Lennard, C., "Evaluation of Techniques for the Detection and Enhancement of Latent Fingermarks on Black Electrical Tape", Jor. Forensic Identification, Vol. 55, no. 2, March/April 2005, pp. 214-231.

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