• 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.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.333-341
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• 2020

Since thermal paper is widely used in daily life such as convenience store receipts, lottery tickets and ATM receipts, it is important to develop fingerprints on thermal papers because it can be easily found in crime scenes. This study compared the ability of fingerprint development between vacuum metal deposition(VMD) and 1,2-indanedione(SOON-100) in order to evaluate the effectiveness of VMD, which some literatures have stated to be effective in thermal papers. As a result, in the case of SOON-100, clear ridges of fingerprints that enable individual identification were observed after an hour of deposition, although the fresh fingerprints were faint. In the case of VMD, the fingerprints gradually spread and the quality of the ridges deteriorated rapidly after 6 hours of deposition. This results is consistent with the principle of VMD. Considering the principles of VMD and the characteristics of the surface of thermal paper, VMD is not suitable for the development of potential fingerprints on the thermal paper.

• The Journal of the Korea Contents Association
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• v.16 no.9
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• pp.247-253
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• 2016

Some previous studies had proven that ninhydrin or its analogues are not effective in developing fingermarks on some types of paper. This study has evaluated the efficiency of four reagents for detecting latent fingermarks on six unusual paper surfaces. Among the six types of paper surfaces, none of the reagents worked on the newspaper. The 1,2-IND/Zn developed fingermarks on most of the surfaces tested.

• Analytical Science and Technology
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• v.28 no.1
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• pp.26-32
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• 2015

The consistency and homogeneity of repetitive printing of artificial fingerprint were evaluated using a visual minutiae comparison method and an Automated Fingerprint Identification System (AFIS). The standard latent fingerprint pattern was prepared by the printing of a master digital fingerprint pattern with an inkjet printer cartridge case filled with artificial sweat. The master digital fingerprint pattern was prepared with a scanning of an inked fingerprint pattern of a living subject. The intensities of the master digital fingerprint pattern were adjusted by changing the 'output level' values of the Adobe Photoshop CS 5 software. Number of standard latent fingerprint patterns were printed and then developed with conventional latent fingerprint developing methods; ninhydrin treatment method and 1,2-indandion(1,2-IND)/$ZnCl_2$ treatment method. The ridge details of the latent fingerprint patterns developed with the reagents were visually compared with the inked fingerprint pattern and could confirm that the minutiae of both patterns are visually identical. The ridge detail of the inked fingerprint and reagent developed standard latent fingerprint patterns were compared with an AFIS. The average number of minutiae searched by the AFIS was $52.4{\pm}2.4$ (range = 48~56) for 50 ninhydrin developed latent fingerprint patterns, and $50.2{\pm}1.9$ (range = 47~53) for 50 1,2-IND/$ZnCl_2$ developed latent fingerprint patterns. These low standard deviation values over 50 repetitive printing demonstrated that the 50 standard latent patterns were printed with consistent and homogeneous manner.

• 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.

• 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.

• Fire Science and Engineering
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• v.32 no.3
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• pp.88-94
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• 2018

Fingerprints deposited on paper found at a fire scene are important evidence for determining a suspect's identity. On the other hand, because the temperature at the fire scene is very high, there are many difficulties in developing fingerprints. This study compared the effectiveness of ninhydrin, DFO, and silver nitrate to develop fingerprints deposited on paper exposed to high temperatures. Using a dry heat press, heat was applied to the paper at $200^{\circ}C$ for various times. Silver nitrate was found to be superior to the others under all conditions. Ninhydrin developed fingerprints weakly compared to DFO and silver nitrate. In addition, the sensitivity of DFO decreased with increasing exposure time. Therefore, it is recommended silver nitrate be used to develop fingerprints deposited on paper found at a fire scene.

• 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.

• The Journal of the Korea Contents Association
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• v.19 no.12
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• pp.527-534
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• 2019

Most of the prints left on the crime scene are latent prints. And, even after the latent prints have been developed, additional enhancement is required and forensic light sources are mainly used. Depending on the applied technique and the light source used, it is difficult to obtain the ideal enhancement effect when the reflected light cannot be cut off well. In this study, we improved the wavelength of the forensic light source by attaching a low-pass filter, resulting in better quality fingerprint images.

• Analytical Science and Technology
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• v.30 no.6
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• pp.312-318
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• 2017

The shelf life of 1,2-indandione/zinc (1,2-IND/Zn) solution and polyvinylpyrrolidone (PVP) solution, which are known as reagents for developing latent fingermarks deposited on the surface of thermal paper, was studied. The standard latent fingermarks used for comparisons were artificial latent fingermarks printed on thermally sensitive and non-sensitive surfaces with the same intensity. Upon treatment of standard latent fingermarks with the pre-mixed 1,2-IND/Zn and PVP solutions, the fingermarks could be successfully developed until 3 days after the preparation of the mixture. However, from the third day after mixing the reagents, blackening was observed on the surface of the thermal paper, indicating deterioration of the reagent performance. The 1,2-IND/Zn and PVP solutions separately stored without mixing in advance were mixed immediately before use, and the development efficiency of the latent fingermarks deposited on the surface of thermal paper was observed. The performance of the PVP solution decreased after 20 days from the preparation of the reagent. It was also found that the shelf life of 1,2-IND/Zn and PVP mixture was determined by the PVP solution. The effect of oxygen and moisture on the degradation of PVP was investigated. It was found that the performance of the PVP solution deteriorated because of the influence of moisture, though it was not affected by oxygen.