Fingerprint developing agent based on fluorescent colloidal particle solution, preparation method and application thereof

A technology of colloidal particles and developing agent, applied in the field of fingerprint display, can solve the problem that occult blood fingerprints are not involved, and achieve the effect of clear display effect, obvious details, bright and clear fingerprint lines

Active Publication Date: 2018-12-18
SUZHOU UNIV
View PDF6 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the reported preparation of conjugated polymer nanoparticles for fingerprint visualization mainly uses small molecules as catalysts (see literature: ACS Appl. Mater. Interfaces 2017, 9, 4908-4915 and J. Colloid Interface Sci. 2018, 528, 200-207), which can directly visualize sweat-latent fingerprints on different objects or after 502 glue fumigation, but does not involve the visualization of blood-occult fingerprints.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Fingerprint developing agent based on fluorescent colloidal particle solution, preparation method and application thereof
  • Fingerprint developing agent based on fluorescent colloidal particle solution, preparation method and application thereof
  • Fingerprint developing agent based on fluorescent colloidal particle solution, preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] This embodiment provides a method for preparing a poly(p-phenylenevinylene) fluorescent colloidal particle solution using branched polyethyleneimine as a catalyst. The specific steps are as follows:

[0044] 1. Refer to the literature (J. Am. Chem. Soc. 1993, 115, 10117-10124) to synthesize monomers without side groups. Under anaerobic conditions, take 1.0053 g (about 2.86 mmol) of monomers and dissolve them in 16 mL of deionized In water, 2 mL of NaOH solution (1 mol / L) was slowly added dropwise under the condition of ice-water bath, and the reaction was stirred for 1 h while maintaining the condition of ice-water bath, then 3 mL of HCl solution (2 mol / L) was added to stop the reaction, and then The reaction solution was put into a dialysis bag with a molecular weight cut-off of 3500 and dialyzed with deionized water for 24 h. The dialysate was the prepared PPV precursor (pre-PPV) solution. Add water to make up to 25 mL and put it into a glass bottle , stored in the re...

Embodiment 2

[0055] This embodiment provides a sweat-latent fingerprint on the surface of the aluminum foil object. Use the fingerprint visualization agent based on the fluorescent colloidal particle solution prepared in Example 1 to perform sweat-latent fingerprint visualization to obtain a fingerprint image under ultraviolet light. The specific steps are as follows:

[0056] 1. Completely immerse the aluminum foil with latent fingerprints of fresh sweat in the developer solution provided in Example 1 for 3 minutes to ensure full contact between the fingerprint and the developer solution.

[0057] 2. After removing the aluminum foil from the developer solution, rinse the aluminum foil in a 10 mL weighing bottle for 2 to 3 times to wash off the excess developer solution sticking to the object of the aluminum foil.

[0058] 3. After drying the rinsed aluminum foil, observe bright and clear yellow-green fingerprint lines under the excitation of a portable ultraviolet lamp (wavelength: 365nm),...

Embodiment 3

[0061] This embodiment provides a blood occult fingerprint aimed at the surface of the aluminum foil object, which is visualized with a poly(p-phenylenevinylene) fluorescent colloid particle developer solution containing branched polyethyleneimine to obtain a fingerprint image under ultraviolet light. The specific steps are as follows :

[0062] 1. Completely immerse the aluminum foil with the fingerprints of fresh occult blood in 5 mL of absolute ethanol for 2-3 minutes to ensure full contact between the fingerprints and absolute ethanol.

[0063] 2. Take the aluminum foil out of absolute ethanol and let it dry naturally, then completely immerse it in the developer solution provided in Example 1 for 3 minutes to ensure full contact between the fingerprint and the developer solution.

[0064] 3. After taking out the aluminum foil from the developer solution, rinse the aluminum foil in a 10 mL weighing bottle for 2 to 3 times to wash off the excess developer solution sticking t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a fingerprint developing agent based on a fluorescent colloidal particle solution, a preparation method and an application thereof. A PPV precursor solution is prepared by a Wessling sulfonium salt precursor method, an anionic surfactant is added, the branched polyethyleneimine is used as a catalyst, and a PPV colloidal particle solution containing branched polyethyleneimine in the solution is obtained by self-assembly of a polymer chain during elimination process. An immersion method is used, the sweat latent fingerprints and occult blood fingerprints on different objects are visualized, and clear and bright fingerprint lines can be observed under ultraviolet light, are suitable for fingerprint identification. The PPV colloidal particle developing solution providedby the invention has simple preparation process and convenient operation, can overcome the interference of complex background patterns, and develops sweat latent fingerprints and occult blood fingerprints on different objects; the developing agent is an aqueous dispersion, which is environmentally friendly, and can be used multiple times, saves cost, and is suitable for industrial production andconventional fingerprinting work.

Description

technical field [0001] The invention relates to a fingerprint display technology, in particular to a fingerprint display agent based on a fluorescent colloid particle solution, a preparation method, and a fingerprint display method for sweat latent fingerprints and latent blood fingerprints on different objects, belonging to the application of polymer fluorescent materials field. Background technique [0002] Fingerprints have been hailed as "the first physical evidence" since ancient times, and they play a very important role in criminal investigation and inspection and identification. At crime scenes, common fingerprints are mainly divided into three categories: visible fingerprints, plastic fingerprints, and latent fingerprints. Among them, latent fingerprints are one of the most common physical evidence in current criminal investigation cases, and latent fingerprints can be divided into sweat latent fingerprints and blood latent fingerprints. [0003] At present, for s...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08J3/03C09K11/06A61B5/1172C08L65/00
CPCA61B5/1172C08J3/03C08J2365/00C08J2479/02C09K11/06C09K2211/1425
Inventor 范丽娟吴铭樊智楠
Owner SUZHOU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products