• Analytical Science and Technology
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• v.32 no.3
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• pp.105-112
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• 2019

Fingerprints may be contaminated with ethanol solutions. In order to solve the case, the law enforcement agency may need to visualize the fingerprint from these samples, but the development method has not been studied. The paper with latent fingerprint was contaminated with ethanol solution and then the blurring of ridge detail was observed. As a result, when the copy paper was contaminated with ethanol solutions of less than 75 % (v/v), the amino acid components of latent fingerprint residue blurred but lipid components of latent fingerprint residue didn't blurred. On the other hand, when the paper was contaminated with ethanol solution of more than 80 % (v/v), the amino acid components of latent fingerprint didn't blurred but the lipid components of latent fingerprint blurred. Therefore, it is found that the paper contaminated with ethanol solutions of less than 75 % (v/v) should be treated by oil red O (ORO) enhancing lipid components, and the paper contaminated with ethanol solutions of 80 % (v/v) or more should be treated by 1,2-indandione/zinc (1,2-IND/Zn) enhancing amino acid components. The blurring of ridge detail was not observed when the fingerprints were deposited with fingers contaminated with ethanol solution. This fingerprints were treated with 1,2-IND/Zn or ORO to compare the latent fingerprint development ability, and using 1,2-IND/Zn was able to visualize the latent fingerprint more clearly than using ORO.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.1
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• pp.99-103
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• 2024

Previous artificial latent fingerprint solution has shown unsatisfactory results. Therefore, in this study, we developed an artificial latent fingerprint solution close to the actual fingerprint composition by improving the lipid composition. We mixed lipid solution with amino acid solution at v/v ratios as follows: 2:3, 1:4, 1:5, 1:8, 1:10, 1:20. We then dropped the same amount of each proportion of artificial latent fingerprint solution on porous paper and non-porous slide glass. Subsequently, each sample was treated with Oil red O, Cyanoacrylate fuming and Basic yellow 40 staining. As the concentration of lipids decreased, the output also decreased. Both types of surfaces and all concentrations were visually confirmed very well. In addition, the reactivity to lipids was significantly higher compared to the previous artificial latent fingerprint solution. Furthermore, for the quantitative evaluation, it is necessary to conduct additional research on the printing of the artificial latent fingerprint solution.

• Analytical Science and Technology
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• v.21 no.3
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• pp.222-228
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• 2008

On living skin the chances of a successfully developing latent fingerprint are very limited. This is due to the fact that continual perspiration and rapid absorption diffuse into the lipophillic layer on skin. A study was conducted to investigate effectively developing method of latent fingerprints on human skin surfaces and pig skin likely corpse's skin. We used commercial fingerprint powder, black powders, black magnetic powder, fluorescence magnetic powder, Cyanoacrylate fuming (CA) and direct lifting methods (lifting paper, glasses and photo glossy paper). Developing of fresh fingerprints on living skin was achieved with S-powderblack, CA fuming and CA fuming following S-powder, fluorescence powder. The other powder tends to overwhelm the latent print and the background. But, latent fingerprint residue was disappeared with time after deposit on a living surface. In case of pig skin likely corpse's skin, latent fingerprint detection was achieved with CA fuming following S-powder and deposited print during 6 hr at $25^{\circ}C$, 40% relative moisture yielded excellent fingerprints with clear ridge details using 1 min CA fuming. And enhancement of fingerprint detection image using forensic light source was achieved.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.209-216
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• 2016

Latent fingerprint left on the adhesive sides of tapes can be easily found at a crime scene. Small Particle Reagents(SPR) based on iron oxide($Fe_3O_4$) is a technique for the detection of a latent fingerprint adhesive surface. In this study, found out that the causes affecting the quality of the fingerprints developed when used SPR based on iron oxide. To a suspension of 0.5g of iron oxide in 100ml of distilled water, 0.5ml or more surfactant were added can be developed latent fingerprints of good quality. In addition, using surfactants HLB(hydrophile-lipophile balance) value of 11~18 showed good contrast to the background and latent fingerprint.

• Analytical Science and Technology
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• v.25 no.3
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• pp.164-170
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• 2012

Cyanoacrylate fuming mehod is effective for latent fingerprints developing on non-porous surfaces. In this study, we investigated optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber. The effects of temperature, relative humidity, fuming method and processing time were checked throughly. The amount of evaporated cyanoacrylate was increased at higher temperature, but cyanoacrylate polymerization on the fingerprint ridge was best at $30^{\circ}C$. With a relative humidity of 40% to 50% conditions, good quality of fingerprints were developed. If a relative humidity is lower than 30% or higher than 60%, polymerization rate of cyanoacrylate monomers on the fingerprint ridge was decreased. It was identified that application of $OMEGA-PRINT^{TM}$ dispersal pad or cotton ball with sodium hydroxide fuming method in vacuum chamber was more effective than natural fuming method. We found that cyanoacrylate processing time in vacuum chamber did not have more significant than relative humidity.

• Analytical Science and Technology
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• v.22 no.2
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• pp.166-171
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• 2009

Powder method is simple and very effective method for developing latent finger and palm print in crime scene. This technique has been actively studied to enhance effectiveness. In general, the evaluation for developing powder is mainly performed by the subjective opinion of researcher from comparison of the results obtained with existing and new one to develope finger and palm deposition. The purpose of this work is to present objective method of powder-treated latent fingerprint for evaluating method by developing efficiency. We indicated three evaluating methods of objective developing efficiency, which are measuring the number of minutiae in same sections on print, scattering level of developing reagent and contrast between developing reagent and background materials.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.964-971
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• 2014

It is impossible to use general latent fingerprint developing reagents with thermal paper because it is very sensitive to change its color when exposed to heat and polarized solvents. The present study set up the applicapable ratio of 1,2-Indanedione solution demonstrating the effect of zinc chloride. There is no difference in results and the term of validity in solution containing under 3% of polarized solvent. And the solution without zinc chloride has better result in fluorescence.

• The Journal of the Korea Contents Association
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• v.17 no.8
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• pp.579-585
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• 2017

Powder method is one of the most commonly used techniques for developing latent fingerprints on non-porous surfaces. While fingerprint powders become more diverse, there is no standard for the number of stroking a brush. For this reason, crime scene investigators need to stroke a brush as they try to figure out how much latent fingerprints are developed. Also, results vary from individual to individual. According to the combination of material and manufacturing, there are various results that powder particles hold together. It is called auto-adhesion which means the interaction between powder particles. This study showed auto-adhesion of 13 kinds of fingerprint powders expanding the number of stroking time. Consequently, some fingerprint powders had strong auto-adhesive property and others had weak auto-adhesion. Furthermore, the others did not change.

• Analytical Science and Technology
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• v.21 no.3
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• pp.212-221
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• 2008

In order to investigate the information for effective detection and developing of latent fingerprints, we identified fatty acids composition of latent fingerprints on non-porous evidence surface and the chemical changes of latent fingerprint residue after print deposition during 7 months. Fingerprints from eight Korean male donors (aged 29-50 years) and one female donor (aged 36 years) were collected. All fingerprints were found to contain lauric acid (C12:0), myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), elaidic acid (C18:1n9t), oleic acid (C18:1n9c), linoleic acid (C18:2n6c), arachidic acid (C20:0), linolenic acid (C18:3n3), erucic acid (C22:1n9) and docosadienoic acid (C22:2) and primarily palmitic acid (35.45-48.37%), oleic acid (14.84-28.49%), stearic acid (9.71-24.96%) and linoleic acid (7.68-18.8%) occupied 75% of total fatty acids. When the fingerprints were deposited at dark room for 7 months, total fatty acids components decreased about 12-25%. It can be explained that significant degradation of long-chain fatty acids such as elaidic acid (C18:1n9t), arachidic acid (C20:0), linolenic acid (C18:3n3), erucic acid (C22:1n9), and docosadienoic acid (C22:2) resulted in the generation of myristic acid (C14:0), myristoleic acid (C14:1) and pentadecanoic acid (C15:0).

• Analytical Science and Technology
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• v.33 no.2
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• pp.108-114
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• 2020

Gloves are very important evidence at a crime scene; specifically, rubber gloves can be found easily at homes. Therefore, crime scene investigators attempt to develop fingerprints inside the rubber gloves that are discovered, for identifying unknown suspects. This study compared the effectiveness of three different methods that are used for developing latent prints on gloves with aging time. These were the powder, cyanoacrylate fuming, and multi-metal deposition I methods. The powder method achieved good results for 1-3 days of aged prints, and the cyanoacrylate fuming method worked well on 2-week-old prints. In comparison, multi-metal deposition I method developed good quality fingerprints for 6 weeks of aging time.