• Title/Summary/Keyword: cyanoacrylate fuming

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A study on the optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber (시아노아크릴레이트 진공 훈증법에 의한 잠재지문 현출 최적화에 관한 연구)

  • Yu, Je-Seol;Jung, Jin-Sung;Lim, Seung;Park, Sung-Woo
    • 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.

Comparison of aging fingerprint enhancement by pre-treatment of various initiator powders in the cyanoacrylate fuming method (다양한 개시제(initiator)분말 전처리(pre-treatment)를 통한 노화된 지문의 Cyanoacrylate Fuming법 현출 증강 비교)

  • Kim, Kyung-Soo;Lee, Yoon-Jeong;Seo, Kyung-Suk
    • Analytical Science and Technology
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    • v.35 no.3
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    • pp.129-135
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    • 2022
  • We tested the pre-treatment of alumina, leucine, alumina mixed with leucine at ratios of 9:1 (Al-Leu (9:1)) and 5:1 (Al-Leu (5:1)), and alumina mixed with sodium lactate at a ratio of 5:1 (Al-Lac (5:1)) on aged fingerprints (1, 7, 14, and 30 days after natural fingerprinting) before cyanoacrylate (CA) fuming to improve the development efficacy. As a result of the experiment, fingerprints with pre-treatment of alumina, leucine, Al-Leu (9:1), Al-Leu (5:1), and Al-Lac (5:1) showed better development efficacy (area and minutiae) than fingerprints without pre-treatment. Therefore, this modified CA fuming method improved the development efficacy with five pretreatments.

A Study on How to Improve Empty Print to Cyanoacrylate Fuming Developed by Vacuum Metal Deposition (Vacuum Metal Deposition으로 현출된 Empty Print를 Cyanoacrylate Fuming로 개선하는 방법에 관한 연구)

  • Lee, Wonyoung;Kim, Youjin;Lee, Munhee;Yu, Jeseol
    • The Journal of the Korea Contents Association
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    • v.21 no.12
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    • pp.331-336
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    • 2021
  • Vacuum metal deposition(VMD) using gold and zinc is known as a very sensitive technique of developing latent fingerprints on nonporous surfaces by excellent malleability and ductility of gold. However, VMD produces empty print which cannot be identified. There is only presumption about the cause of occurrence of empty print, the exact cause is not known. In this study, we experiment on the freshness of fingerprints and sensitivity of techniques that are estimated as the factors causing empty print, based on this, we suggest cyanoacrylate fuming is effective to redevelop empty print.

Developing of latent fingerprint on human skin (생체피부에서의 잠재지문 현출)

  • Lee, Hee-Il;Choi, Mi-Jung;Kim, Jai-Hoon;Park, Sung-Woo
    • 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.

Latent fingerprint development from rubber gloves using MMD I (Multimetal deposition I)

  • An, Jaeyoung;Kim, Heesu;Oh, Jungmin;Han, Sooyong;Yu, Jeseol
    • 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.

Mixture of dimethylaminobenzaldehyde and cyanoacrylate to develop fingerprints with fluorescence: a preliminary test

  • Lee, Wonyoung;An, Jaeyoung;Yu, Jeseol
    • Analytical Science and Technology
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    • v.35 no.1
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    • pp.1-7
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    • 2022
  • This study suggests a new one-step fluorescent cyanoacylate-fuming method for developing fingerprints by using a CAB mixed with dimethylaminobenzalde (DMAB) and cyanoacylate (CA) in a specific ratio. CAB is prepared by mixing 2.5 % (w/w) DMAB with CA and fumigated at 180 ℃. Under these conditions, developing fingerprints showed the best results. The fuming method using CAB develops latent fingerprints into fluorescence and has a higher sensitivity than CA, and it showed comparable or better contrast to existing fluorescence enhancement methods. It was also applicable on a variety of non-porous surfaces that can be encountered at ordinary times. This method is more useful than conventional fluorescent dyeing methods in that it minimizes damage to fingerprints or samples, makes it easy to manufacture, saves time, and can use existing current equipment as it is.

A study on Enhancement Effectiveness of Cyanoacrylate Fumed Fingermark by the Solvent of Rhodamine 6G (Rhodamine 6G 용매에 따른 CA 훈증 지문 증강 효과에 관한 연구)

  • Shim, Yea-Ra;Yu, Je-Seol
    • The Journal of the Korea Contents Association
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    • v.17 no.7
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    • pp.294-302
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    • 2017
  • In this study, latent fingermarks deposited in porous or non-porous surface was developed by cyanoacrylate fuming, and then the developed fingermark is enhanced by using Rhodamine 6G. Between water-based R6G and organic solvent-based R6G, author studied about which material have higher effectiveness in enhancing fingermark. In all seven types of surfaces depositing fingermark, water-based R6G have higher effectiveness in enhancing fingermark and lower surface coloring than organic solvent-based R6G. But because the surfaces found in crime scene have multicolor background and various quality, the additional study about various surfaces is needed.

A study on the distribution of latent fingerprints on paper knife sheaths (간이 칼집에서의 잠재지문 분포에 관한 연구)

  • Kim, Hyo-Mi;Park, Gi-Hyun;Lee, Su-Bhin;Yu, Je-Seol
    • Analytical Science and Technology
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    • v.34 no.6
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    • pp.251-258
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    • 2021
  • Knives are most frequently used as weapons in violent crimes. Criminals leave behind knife sheaths made of paper and tape at crime scenes. It is difficult to develop fingerprints using tape attached to a porous surface, resulting in the need to explore effective techniques for identifying fingerprints as well as the distribution of fingerprints on each surface, when evidence such as paper knife sheaths are found. In this study, 50 knife sheaths were prepared. The cyanoacrylate fuming (CA fuming) method was applied to develop fingerprints on the non-adhesive side of the tape, and a dual-purpose 1,2-indanedione/Zn (1,2-IND/Zn) reagent was used to separate tape from paper while simultaneously developing fingerprints on the paper. The fingerprints on the adhesive side of the tape were developed using Wet Powder Black®. Using the R statistical analysis program (The R Foundation for Statistical Computing), we used a heat map to indicate the location of fingerprints developed from each surface. More fingerprints were detected at the ends than in the center of the adhesive side of the tape, and although the non-adhesive sides of tape and paper did not present clear distribution patterns, many fingerprints were developed that had sufficient clarity for personal identification. The results of this study may be applicable for processing evidence when paper sheaths are found at crime scenes.

Development of Aged Fingermarks Deposited on Expanded Polystyrene(Styrofoam) Using Multi-metal Deposition I(MMD I) (Multi-metal Deposition I(MMD I)을 사용한 스티로폼 표면의 오래된 지문 현출)

  • Kim, Chae-Won;An, Jae-Young;Yu, Je-Seol
    • The Journal of the Korea Contents Association
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    • v.20 no.3
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    • pp.687-694
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    • 2020
  • Styrofoam is one of the most commonly used materials in everyday life, such as various packaging containers, toys, and buoys, and is likely to be found in crime scenes. However, due to the structural characteristics of Styrofoam, fingerprints cannot be deposited well. According to previous researches, powdering or cyanoacrylate fuming method was applied for developing fingerprints on Styrofoam. The purpose of this study was to investigate the effect of MMD I through comparative experiments of powdering. As a result of applying powder method and MMD I, MMD I was more effective than powder method on styrofoam.

Washing effect of fingermark contaminated with flammable liquids (인화성액체에 오염된 지문의 세척 효과)

  • Ho-Won, Jang;Ji-Yun, Kwon;Hyo-Mi, Kim;Seung-Ju, Yoo;Sungwook, Hong
    • Analytical Science and Technology
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    • v.35 no.6
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    • pp.237-241
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    • 2022
  • The effect of washing fingerprints deposited on glass that were contaminated with a flammable liquid (gasoline, kerosene, diesel, and thinner) was studied by washing with hexane or heptane. The fingerprints were visualized using fuming cyanoacrylate, followed by basic yellow 40 staining. After comparing the washing effect, by dividing one fingerprint into four sections, it was confirmed that the ridge detail was damaged by dissolving the fingerprints in flammable liquid. As a result of washing fingerprints contaminated with flammable liquids using hexane or heptane, fingerprints contaminated with gasoline, kerosene, and thinner did not show a washing effect because the ridge detail was damaged at the time of contamination, and only fingerprints contaminated with diesel exhibited improved ridge detail quality. Because hexane and heptane washing damage the ridge detail, it was found that fingerprints contaminated with gasoline, kerosene, and thinner were better enhanced directly without the washing process. In addition, it was found that the amount of the washing solvent and contact time should be minimized when washing fingerprints contaminated with diesel.