CN112175449B - Super-stable printable aqueous fluorescent anti-counterfeiting ink and preparation method thereof - Google Patents
Super-stable printable aqueous fluorescent anti-counterfeiting ink and preparation method thereof Download PDFInfo
- Publication number
- CN112175449B CN112175449B CN202011281379.XA CN202011281379A CN112175449B CN 112175449 B CN112175449 B CN 112175449B CN 202011281379 A CN202011281379 A CN 202011281379A CN 112175449 B CN112175449 B CN 112175449B
- Authority
- CN
- China
- Prior art keywords
- solution
- aqueous solution
- aqueous
- quantum dots
- quantum dot
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D11/00—Inks
- C09D11/50—Sympathetic, colour changing or similar inks
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D11/00—Inks
- C09D11/30—Inkjet printing inks
- C09D11/38—Inkjet printing inks characterised by non-macromolecular additives other than solvents, pigments or dyes
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Organic Chemistry (AREA)
- Inks, Pencil-Leads, Or Crayons (AREA)
- Ink Jet Recording Methods And Recording Media Thereof (AREA)
Abstract
The invention provides an ultra-stable printable aqueous fluorescent anti-counterfeiting ink and a preparation method thereof, wherein the aqueous fluorescent anti-counterfeiting ink is prepared by the following steps: 1) preparing a quantum dot aqueous solution; 2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/A/B quantum dot aqueous solution, diluting the quantum dots, and adjusting the pH value of the solution to 6.0-10.0 by using a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink. The quantum dot fluorescent ink provided by the invention is low in concentration, high in fluorescence intensity and strong in storage stability, is a light yellow or light red transparent liquid under ordinary illumination, and a printed pattern cannot be seen under ordinary illumination, and shows a clear fluorescent pattern under 365nm ultraviolet excitation, so that the anti-counterfeiting property and the confidentiality are high.
Description
Technical Field
The invention relates to the technical field of ink-jet printing ink, in particular to ultrastable printable aqueous fluorescent anti-counterfeiting ink and a preparation method thereof.
Background
Along with the attention of people to information safety and file privacy protection and the rapid development of anti-counterfeiting technology and printing technology, the traditional anti-counterfeiting ink taking an organic solvent as a medium cannot meet the requirement of current printing, the novel functional ink with the characteristics of anti-counterfeiting, safety and environmental protection becomes one of research hotspots in the fields of materials and devices, the anti-counterfeiting ink is required to meet the technical requirement of printing, and the novel functional ink has strong information safety protection capability and cannot harm human bodies and the environment.
The ink based on the fluorescent nano material is widely researched and applied in the fields of product anti-counterfeiting, important file protection, information encryption and the like due to good concealment, strong information reproduction capability and convenient detection. Semiconductor Quantum Dots (QDs) are zero-dimensional or quasi-zero-dimensional semiconductor nanocrystals, can be dispersed in water or organic solution to form colloid, have unique physicochemical properties such as wide absorption wavelength, narrow emission peak, high fluorescence quantum yield, strong bleaching resistance and the like compared with other dyes, and are widely researched in the field of fluorescent anti-counterfeiting ink. The existing high-quality quantum dots are usually dispersed in an organic solvent and need to be transferred to a water phase for preparing ink through surface modification, but after the surface modification, the fluorescence of the quantum dots is easily influenced by environmental factors such as temperature, humidity, pH value, ultraviolet light and the like, and the problems of ligand shedding, aggregation and precipitation and the like exist, so that the long-term storage is difficult, and the practical application of the high-quality quantum dots is seriously limited. Therefore, the preparation of the quantum dot fluorescent ink with good dispersibility, stable fluorescence performance, safety and environmental protection has important research significance and application value.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides the ultra-stable printable aqueous fluorescent anti-counterfeiting ink and the preparation method thereof.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
providing an ultra-stable printable aqueous fluorescent anti-counterfeiting ink, wherein the aqueous fluorescent anti-counterfeiting ink is prepared by the following steps:
1) preparing a quantum dot aqueous solution: dissolving a hydrophilic modifier A in water to obtain a hydrophilic modifier A aqueous solution, adding the hydrophilic modifier A aqueous solution into an organic solution of oil-soluble Quantum Dots (QDs), carrying out ultrasonic treatment on the obtained mixed solution for 2-4 hours, standing, taking out an aqueous solution layer containing the QDs/A quantum dots after the mixed solution is layered, gradually dropwise adding the modifier B aqueous solution into the QDs/A quantum dot aqueous solution, then placing the obtained mixed solution in a water bath constant temperature oscillator for 24 hours in a room temperature and light-tight oscillation mode, centrifuging the obtained reaction solution, collecting supernatant, centrifuging, collecting precipitate, dispersing in deionized water, and dialyzing for 24 hours to remove unreacted modifier B to obtain a QDs/A/B quantum dot aqueous solution;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/A/B quantum dot aqueous solution obtained in the step 1), diluting the quantum dots, and adjusting the pH value of the solution to 6.0-10.0 by using a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink.
According to the scheme, the oil-soluble quantum dots are selected from core-shell quantum dots CdSe/ZnS and CdSe/CdS/ZnS, alloy quantum dot Cd x Zn 1–x S、CdSe/Cd x Zn 1–x And (2) one of S, wherein x is more than 0 and less than 1, and the surface ligand of the quantum dot is one or two of tri-n-octyl phosphine oxide (TOPO), tri-n-octyl phosphine, tributylphosphine, 1-octadecene, oleylamine and oleic acid. The oil-soluble quantum dot is prepared by an organic high-temperature cracking method, and the preparation method refers to the following steps: wan Ki Bae, Kookheon Char, Hyuck Hur, and Seonghoon Lee.Single-Step Synthesis of Quantum Dots with Chemical Composition Gradients, chem.Mater.2008,20, 531-539; von 21855pine, preparation and characterization of semiconductor quantum dot-like fluids (D), university of Wuhan theory, 2010; yanli, preparation of silica coated alloy quantum dots and stability study (D), university of wuhan theory, 2015.
According to the scheme, the organic solvent used by the organic solution of the oil-soluble quantum dots is n-hexane or chloroform, and the concentration of the quantum dots is 10-100 mu M (mu mol/L).
According to the scheme, the hydrophilic modifier A in the step 1) is a micromolecule compound with both sulfydryl and carboxyl, the concentration of the aqueous solution of the hydrophilic modifier A is 1-10mM (mmol/L), and the molar ratio of the hydrophilic modifier A to the oil-soluble quantum dots is 100-1000: 1.
preferably, the hydrophilic modifier a is selected from one of thioglycolic acid, mercaptopropionic acid, mercaptobutyric acid, mercaptobenzoic acid, mercaptoundecanoic acid, and dimercaptosuccinic acid.
According to the scheme, the molar ratio of the modifier B to the modifier A in the step 1) is 0.2-5: 1, the modifier B is one of branched polyethyleneimine (PEI, Mw & lt600 & gt- & lt 10000- & gt), polyamidoamine (PAMAM, Mw & lt517 & gt- & lt 14215), octadecylamine polyoxyethylene ether (AC-1810, AC-1812 and AC-1815), and dodecylamine polyoxyethylene ether (AC-1210 and AC-1215). The modifier B is used for further increasing the dispersibility and stability of the quantum dots in water.
According to the scheme, a catalyst is also added into the mixed solution in the step 1), and the catalyst is N, N' -Dicyclohexylcarbodiimide (DCC) and N-hydroxysuccinimide (NHS). The modifier B is combined on the surface of the quantum dot through the action of a proton donor acceptor or amidation reaction under the action of a catalyst, wherein the action of the proton donor acceptor does not need to add the catalyst. DCC acts on dehydration and NHS acts to activate the carboxyl group.
According to the scheme, the concentration of the quantum dots in the aqueous fluorescent anti-counterfeiting ink in the step 2) is 1-10 mu M, and the volume ratio of water to ethanol to glycol is 5-8: 1-2: 1-3. The aqueous fluorescent anti-counterfeiting ink has the advantages that the concentration of quantum dots is too low, the fluorescence intensity is insufficient, and the concentration is too high, so that a printing needle head is easily blocked. Wherein the ethanol reduces the surface tension of the ink, and the glycol adjusts the viscosity of the ink.
According to the scheme, the pH regulator in the step 2) is sodium hydroxide solution or dilute hydrochloric acid.
The invention also comprises a preparation method of the ultrastable printable aqueous fluorescent anti-counterfeiting ink, which comprises the following steps:
1) preparing a quantum dot aqueous solution: dissolving a hydrophilic modifier A in water to obtain a hydrophilic modifier A aqueous solution, adding the hydrophilic modifier A aqueous solution into an organic solution of oil-soluble quantum dots, carrying out ultrasonic treatment on the obtained mixed solution for 2-4 hours, standing, taking out an aqueous solution layer containing QDs/A quantum dots after the mixed solution is layered, gradually dropwise adding a modifier B aqueous solution into the QDs/A quantum dot aqueous solution, then placing the obtained mixed solution into a water bath constant-temperature oscillator to oscillate for 24 hours at room temperature and dark place, centrifuging the obtained reaction solution, collecting supernatant, centrifuging, collecting precipitate, dispersing the precipitate in deionized water, and dialyzing for 24 hours to remove unreacted modifier B to obtain a QDs/A/B quantum dot aqueous solution;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/A/B quantum dot aqueous solution obtained in the step 1), diluting the quantum dots, and adjusting the pH value of the solution to 6.0-10.0 by using a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink.
The application method of the water-based fluorescent anti-counterfeiting ink comprises the following steps: the aqueous fluorescent anti-counterfeiting ink is directly added into an ink box of a common ink-jet printer, and anti-counterfeiting patterns are printed on substrate materials, wherein the substrate materials comprise various tickets such as commercially available non-fluorescent printing paper, bank notes, tickets and the like and various packaging materials.
And the application of the ultrastable printable aqueous fluorescent anti-counterfeiting ink in the aspects of product anti-counterfeiting, file protection and information encryption. The water-based fluorescent anti-counterfeiting ink is invisible under natural light, fluorescent patterns or character information can be displayed only under the irradiation of a 365nm ultraviolet lamp, and information can be encrypted and anti-counterfeiting can be realized.
The quantum dots in the aqueous fluorescent anti-counterfeiting ink are obtained by two-step surface modification of quantum dots synthesized by an organic phase, wherein in the first step, micromolecules containing sulfydryl and carboxyl are combined on the surfaces of the quantum dots through a ligand exchange reaction, oil-soluble quantum dots are transferred to a water phase based on the strong coordination action of the sulfydryl and the quantum dots, in the second step, polyamino macromolecules or amphiphilic surfactants are combined on micromolecule ligands on the surfaces of the quantum dots through an amidation reaction or a proton donor receptor action, and a layer of macromolecule ligands is combined on the surfaces of the micromolecule ligands of the quantum dots. And dispersing the modified quantum dots in water and ethanol to obtain a quantum dot aqueous solution, and then adjusting the concentration, viscosity and pH value to prepare the aqueous fluorescent anti-counterfeiting ink. The quantum dot printing ink can be directly used for printing fluorescent patterns or characters by an ink-jet printer.
The invention has the beneficial effects that: 1. the quantum dot fluorescent ink provided by the invention is low in concentration and strong in fluorescence, takes non-fluorescent printing paper as a printing base material, is a light yellow or light red transparent liquid under common illumination, can not be seen when the printed pattern is under the common illumination, can show a clear fluorescent pattern under the excitation of 365nm ultraviolet light, is high in confidentiality, has excellent monodispersity and fluorescence stability in water, and has wide application prospects in the fields of product anti-counterfeiting, file protection, information encryption and the like; 2. the invention uses water as the main solvent to prepare the fluorescent quantum dot printing ink, the solvent is volatilized during printing, the environment is not polluted, the organic residues in the printed matter are reduced, and the sanitation and safety of users are ensured.
Drawings
FIG. 1 is a TEM image of QDs/MPA/PEI quantum dots prepared in example 1 of the present invention;
FIG. 2 is a photograph of the aqueous fluorescent anti-counterfeiting ink QDs/MPA/PEI prepared in example 1 under natural light and 365nm ultraviolet lamp irradiation;
FIG. 3 is the fluorescence emission spectra of the oil-soluble quantum dot solution used in example 1 and the prepared aqueous fluorescent anti-counterfeiting ink;
FIG. 4 is a graph showing the change of fluorescence intensity of the aqueous QDs/MPA/PEI fluorescent security ink and the aqueous QDs/MPA quantum dot solution prepared in example 1 with time under the excitation of 365nm ultraviolet light;
FIG. 5 shows the fluorescence intensity changes of the aqueous QDs/MPA/PEI fluorescent security ink and the aqueous QDs/MPA quantum dot solution prepared in example 1 before and after being placed in the dark at room temperature for 60 days;
FIG. 6 shows the fluorescence intensities of the QDs/MPA/PEI aqueous fluorescent anti-counterfeiting ink prepared in example 1 at different pH values;
FIG. 7 is a photograph of the sample (letters: WHUT) printed in example 1 under natural light and under 365nm ultraviolet lamp, and a photograph of a printed clover pattern under natural light and under 365nm ultraviolet lamp.
Detailed Description
In order to make the technical solutions of the present invention better understood, the present invention is further described in detail below with reference to the accompanying drawings.
Example 1
An ultra-stable printable aqueous fluorescent anti-counterfeiting ink, which is prepared by the following steps:
1) preparing a quantum dot aqueous solution: mercaptopropionic acid (MPA) was dissolved in 10mL of water to prepare a 10mM aqueous solution, and 10mL of 10. mu.M CdSe/Cd x Zn 1–x Trichloromethane solution of S alloy quantum dots (x is more than 0 and less than 1, and the surface ligand of the quantum dots is oleic acid), then carrying out ultrasonic dispersion treatment on the obtained mixed solution for 2 hours, standing for 10min, then layering the liquid, taking out the upper layer solution, namely QDs/MPA quantum dot aqueous solution, adding 20 mu mol of N, N-Dicyclohexylcarbodiimide (DCC) and 20 mu mol of N-hydroxysuccinimide (NHS), weighing 20 mu mol of branched polyethyleneimine (PEI, Mw is 600), and completely carrying out ultrasonic-assisted treatment on the branched polyethyleneimineDispersing in 10mL of distilled water, gradually dropwise adding into a QDs/MPA quantum dot aqueous solution, binding PEI on the surface of a quantum dot through amidation reaction with MPA, then placing the mixed solution in a water bath constant temperature oscillator to oscillate at room temperature and dark place (200r/min) for 24 hours, centrifuging the obtained reaction solution for 10min under the condition of 1000r/min to remove unreacted quantum dot, collecting supernatant, centrifuging for 10min at 8000r/min, collecting precipitate, dispersing in 5mL of deionized water, placing in a dialysis bag with the retention rate of 3500 for dialysis to remove redundant MPA, PEI and reaction products of the MPA and the PEI, collecting the solution in the dialysis bag, and obtaining the QDs/MPA/PEI quantum dot aqueous solution;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/MPA/PEI quantum dot aqueous solution obtained in the step 1), wherein the weight ratio of water: ethanol: the volume ratio of the ethylene glycol is 5: 2: and 3, adjusting the pH value of the solution to 8.0 by taking a 1.0mM sodium hydroxide aqueous solution as a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink, wherein the concentration of the quantum dots is 1 mu M. The fluorescent pattern can be seen by observing under 365nm ultraviolet lamp after printing with the ink.
The transmission electron microscope picture of the QDs/MPA/PEI quantum dot prepared by the embodiment is shown in figure 1, and the picture shows that the quantum dot has no obvious agglomeration phenomenon, which indicates that the quantum dot has good dispersibility.
The oil-soluble quantum dots and the prepared aqueous fluorescent anti-counterfeiting ink used in the embodiment are transparent and light yellow under natural light (fig. 2a), which shows that the ink is uniform and stable; under 365nm ultraviolet light, bright green fluorescence can be emitted (fig. 2b), which indicates that the ink has a remarkable anti-counterfeiting characteristic.
Oil soluble Quantum dot solution (CdSe/Cd) used in this example x Zn 1–x Trichloromethane solution of S alloy quantum dots) and the prepared aqueous fluorescent anti-counterfeiting ink have fluorescence emission spectra shown in figure 3, and it can be seen that before and after the quantum dots are modified, the fluorescence emission peaks are narrow and symmetrical, no red shift or blue shift occurs, the fluorescence intensity remains 70% before the modification, which indicates that the modification does not obviously damage the quantum dot structure, and the original fluorescence performance of the quantum dots is basically maintained.
Fig. 4 is a graph showing the change of fluorescence intensity of the QDs/MPA/PEI aqueous fluorescent anti-counterfeiting ink and the QDs/MPA quantum dot aqueous solution prepared in this embodiment with time under 365nm ultraviolet excitation, where the fluorescence intensity of the QDs/MPA/PEI aqueous fluorescent anti-counterfeiting ink is substantially unchanged within 60min under 365nm ultraviolet excitation, which indicates that the fluorescent ink has excellent light stability, and the fluorescence intensity of the QDs/MPA quantum dot modified by MPA is first enhanced and then weakened under 365nm ultraviolet excitation, which indicates that the light stability of the quantum dot can be further improved by combining with PEI.
Fig. 5 shows the fluorescence intensity change of the QDs/MPA/PEI aqueous fluorescent anti-counterfeit ink and the QDs/MPA quantum dot aqueous solution prepared in this embodiment before and after being placed in dark at room temperature for 60 days, and the fluorescence intensity of the QDs/MPA/PEI ink is substantially unchanged after being placed in dark at room temperature for 60 days, which indicates that the fluorescent ink has excellent time stability, whereas the fluorescence intensity of the QDs/MPA quantum dot modified by MPA alone is significantly reduced within 10 days, and the fluorescence intensity is reduced by 90% after 60 days, which indicates that the time stability of the quantum dot can be further improved by combining with PEI.
Fig. 6 shows fluorescence intensities of the QDs/MPA/PEI aqueous fluorescent anti-counterfeiting ink prepared in this embodiment at different pH values, where PEI on the surface of the quantum dot has a large number of amino groups, and in different pH environments, the protonation degrees of the amino groups on the ligand are different, resulting in different fluorescence intensities of the quantum dot, and the fluorescence intensity of the quantum dot in the solution is kept stable within a range of pH 6 to 10.
The picture (letters WHUT and clover patterns) printed by the aqueous fluorescent anti-counterfeiting ink prepared by the embodiment under the irradiation of natural light and a 365nm ultraviolet lamp is shown in figure 7, the picture printed by the aqueous fluorescent anti-counterfeiting ink can not be seen under the common illumination, and a clear fluorescent pattern appears under the excitation of the 365nm ultraviolet light, which shows that the aqueous fluorescent anti-counterfeiting ink prepared by the embodiment has excellent anti-counterfeiting and information encryption performances on characters and patterns.
Example 2
An ultra-stable printable aqueous fluorescent anti-counterfeiting ink, which is prepared by the following steps:
1) preparing a quantum dot aqueous solution: dissolving thioglycolic acid (TGA) in 10mL of water to prepare an aqueous solution with the concentration of 1mM, adding a normal hexane solution of CdSe/ZnS core-shell quantum dots (surface ligands of the quantum dots are oleic acid and tri-N-octylphosphine, the concentration is 1 mu M, and the volume is 10mL), carrying out ultrasonic treatment on the obtained mixed solution for 2 hours, standing for 10 minutes, then layering the liquid, taking out an upper layer solution, namely a QDs/TGA aqueous solution, adding 20 mu mol of N, N' -Dicyclohexylcarbodiimide (DCC) and 20 mu mol of N-hydroxysuccinimide (NHS), weighing 20 mu mol of polyamide (PAMAM, Mw 517), completely dissolving the obtained upper layer solution in 10mL of distilled water under the assistance of ultrasonic, gradually dropwise adding the obtained solution into the QDs/MPA aqueous solution, binding the PAMAM on the surface of the quantum dots through amidation reaction with the TGA, and then placing the mixed solution in a water bath oscillator to be protected from light at room temperature for 24 hours at 200r/min, centrifuging the obtained reaction liquid for 10min at 1000r/min to remove unreacted quantum dots, collecting supernatant, centrifuging for 10min at 8000r/min, collecting precipitate, dispersing in 5mL deionized water, dialyzing in a dialysis bag with an interception rate of 3500 to remove redundant TGA, PAMAM and reaction products of the TGA and the PAMAM, and collecting the solution in the dialysis bag to obtain QDs/TGA/PAMAM quantum dots;
2) preparing water-based fluorescent anti-counterfeiting ink: adding the QDs/TGA/PAMAM quantum dot aqueous solution obtained in the step 1) into water, ethanol and glycol, wherein the weight ratio of water: ethanol: the volume ratio of the ethylene glycol is 8: 1: 1, using 1.0mM sodium hydroxide aqueous solution as a pH regulator to regulate the pH value of the solution to 10.0, and obtaining the aqueous fluorescent anti-counterfeiting ink, wherein the concentration of the quantum dots is 1 mu M. The fluorescent pattern can be seen by observing under 365nm ultraviolet lamp after printing with the ink.
Example 3
An ultra-stable printable aqueous fluorescent anti-counterfeiting ink, which is prepared by the following steps:
1) preparing a quantum dot aqueous solution: mercaptoundecanoic acid (MUA) was dissolved in 10mL of water to prepare an aqueous solution with a concentration of 5mM, and Cd was added x Zn 1–x An n-hexane solution of S alloy quantum dots (surface ligands are oleylamine and tri-n-octylphosphine, the concentration is 10 mu M, and the volume is 10mL), carrying out ultrasonic treatment on the obtained mixed solution for 2 hours, standing for 10min, layering the liquid, taking out a lower layer solution, namely a QDs/MUA aqueous solution, weighing 100 mu mol of octadecylamine polyoxyethyleneAn alkenyl ether (AC-1815, Mw-445.7), and was completely dissolved in 10mL of distilled water with the aid of ultrasound, gradually dripping into QDs/MUA aqueous solution, combining AC-1815 on the surface of the quantum dot through the action of a proton donor acceptor of MUA, then the mixed solution is put into a water bath constant temperature oscillator to be oscillated for 24 hours under the condition of 200r/min at room temperature and dark, centrifuging the obtained reaction solution for 10min under the condition of 1000r/min, to remove the unreacted quantum dots, collecting the supernatant, centrifuging for 10min at 8000r/min, collecting the precipitate, dispersing in 5mL deionized water, placing the solution in a dialysis bag with the cut-off rate of 3500 for dialysis to remove redundant MUA, AC-1815 and reaction products of the MUA and the AC-1815, and collecting the solution in the dialysis bag to obtain QDs/MUA/AC-1815 quantum dots;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/MUA/AC-1815 quantum dot aqueous solution obtained in the step 1), wherein the weight ratio of water: ethanol: the volume ratio of the ethylene glycol is 7: 1: 2. and (3) adjusting the pH value of the solution to 6 by using 1.0mM dilute hydrochloric acid as a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink, wherein the concentration of the quantum dots is 10 mu M. The fluorescent pattern can be seen by observing under 365nm ultraviolet lamp after printing with the ink.
Example 4
An ultra-stable printable aqueous fluorescent anti-counterfeiting ink, which is prepared by the following steps:
1) preparing a quantum dot aqueous solution: dimercaptosuccinic acid (DMSA) is dissolved in 10mL of water to prepare an aqueous solution with the concentration of 3mM, and Cd is added x Zn 1–x Carrying out ultrasonic treatment on the obtained mixed solution for 2 hours, standing for 10 minutes, layering the liquid, taking out the lower layer solution, namely a QDs/DMSA aqueous solution, weighing 80 mu mol of octadecylamine polyoxyethylene ether (AC-1215, Mw is 273.5), completely dissolving the solution in 10mL of distilled water under the assistance of ultrasonic, gradually dropwise adding the solution into the QDs/DMSA aqueous solution, combining the AC-1215 on the surface of the quantum dot through the action of a proton donor acceptor of DMSA, placing the mixed solution in a water bath constant temperature oscillator for 24 hours under the condition of keeping out of light at room temperature for 200r/min, and obtaining a productCentrifuging the reaction solution for 10min at 1000r/min to remove unreacted quantum dots, collecting supernatant, centrifuging for 10min at 8000r/min, collecting precipitate, dispersing in 5mL deionized water, dialyzing in a dialysis bag with cut-off rate of 3500 to remove redundant DMSA, AC-1215 and reaction products of the DMSA and AC-1215, and collecting solution in the dialysis bag to obtain QDs/DMSA/AC-1215 quantum dots;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/DMSA/AC-1215 quantum dot aqueous solution in the step 1), wherein the weight ratio of water: ethanol: the volume ratio of the ethylene glycol is 6: 2: 2. and (3) adjusting the pH value of the solution to 6.5 by using 1.0mM dilute hydrochloric acid as a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink, wherein the concentration of the quantum dots is 10 mu M. The fluorescent pattern can be seen by observing under 365nm ultraviolet lamp after printing with the ink.
Example 5
An ultra-stable printable aqueous fluorescent anti-counterfeiting ink, which is prepared by the following steps:
1) preparing a quantum dot aqueous solution: dissolving mercaptobenzoic acid (MBA) in 10mL of water to prepare an aqueous solution with the concentration of 6mM, adding a normal hexane solution of CdSe/ZnS core-shell quantum dots (surface ligands of the quantum dots are oleic acid and tri-n-octylphosphine, the concentration is 10 mu M, and the volume is 10mL), carrying out ultrasonic treatment on the obtained mixed solution for 2 hours, standing for 10 minutes, layering the liquid, taking out a lower layer solution, namely a QDs/MBA aqueous solution, weighing 80 mu mol of octadecylamine polyoxyethylene ether (AC-1210, Mw is 273.5), completely dissolving the solution in 10mL of distilled water under the assistance of ultrasonic, gradually dripping the solution into the QDs/MBA aqueous solution, combining the AC-1210 with the surface of the quantum dots through the action of a proton donor receptor of the MBA, placing the mixed solution in a water bath constant temperature oscillator, keeping out of light at room temperature for 200r/min, oscillating for 24 hours, centrifuging the obtained reaction solution for 10 minutes under the condition of 1000r/min, removing unreacted quantum dots, collecting supernatant, centrifuging at 8000r/min for 10min, collecting precipitate, dispersing in 5mL deionized water, placing in a dialysis bag with a cut-off rate of 3500, dialyzing to remove redundant MBA, AC-1210 and reaction products of MBA and AC-1210, and collecting solution in the dialysis bag to obtain QDs/MBA/AC-1210 quantum dots;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/MBA/AC-1210 quantum dot aqueous solution obtained in the step 1), wherein the weight ratio of water: ethanol: the volume ratio of ethylene glycol is 6: 2: 2. and (3) adjusting the pH value of the solution to 6 by using 1.0mM dilute hydrochloric acid as a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink, wherein the concentration of the quantum dots is 5 mu M. The fluorescent pattern can be seen by observing under 365nm ultraviolet lamp after printing with the ink.
Example 6
An ultra-stable printable aqueous fluorescent anti-counterfeiting ink, which is prepared by the following steps:
1) preparing a quantum dot aqueous solution: dissolving mercaptoundecanoic acid (MUA) in 10mL of water to obtain 10mM aqueous solution, and adding CdSe/Cd x Zn 1–x S alloy quantum dot trichloromethane solution (x is more than 0 and less than 1, surface ligand of the quantum dot is oleic acid, concentration is 10 mu M, volume is 10mL), the obtained mixed solution is treated by ultrasonic for 2 hours, the mixed solution is kept stand for 10 minutes, then liquid is layered, the taken upper layer solution is QDs/MUA aqueous solution, 20 mu mol of N, N' -Dicyclohexylcarbodiimide (DCC) and 20 mu mol of N-hydroxysuccinimide (NHS) are added, 200mg (20 mu mol) of branched polyethyleneimine (PEI, Mw is 10000) is weighed, the upper layer solution is completely dissolved in 10mL of distilled water under the assistance of ultrasonic, the solution is gradually dripped into the QDs/MUA aqueous solution, PEI is combined on the surface of the quantum dot through amidation reaction with MUA, the mixed solution is placed in a water bath constant temperature oscillator to be in room temperature and dark for 24 hours under the condition of 200r/min, the obtained reaction solution is centrifuged for 10 minutes under the condition of 1000r/min, removing unreacted quantum dots, collecting supernatant, centrifuging at 8000r/min for 10min, collecting precipitate, dispersing in 5mL deionized water, placing in a dialysis bag with retention rate of 10000 for dialysis to remove redundant MUA, PEI and reaction products of MUA and PEI, and collecting solution in the dialysis bag to obtain QDs/MUA/PEI quantum dots;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/MUA/PEI quantum dot aqueous solution obtained in the step 1), wherein the ratio of water: ethanol: the volume ratio of the ethylene glycol is 5: 2: 3. and (3) adjusting the pH value of the solution to 8.0 by taking a 1.0mM sodium hydroxide aqueous solution as a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink, wherein the concentration of the quantum dots is 2 mu M. The fluorescent pattern can be seen by observing under 365nm ultraviolet lamp after printing with the ink.
Claims (7)
1. An ultrastable printable aqueous fluorescent anti-counterfeiting ink is characterized by being prepared by the following method:
1) preparing a quantum dot aqueous solution: dissolving a hydrophilic modifier A in water to obtain a hydrophilic modifier A aqueous solution, adding the hydrophilic modifier A aqueous solution into an organic solution of oil-soluble quantum dots, carrying out ultrasonic treatment on the obtained mixed solution for 2-4 hours, standing, taking out an aqueous solution layer containing QDs/A quantum dots after the mixed solution is layered, gradually dropwise adding a modifier B aqueous solution into the QDs/A quantum dot aqueous solution, then placing the obtained mixed solution into a water bath constant-temperature oscillator to oscillate for 24 hours at room temperature and dark place, centrifuging the obtained reaction solution, collecting supernatant, centrifuging, collecting precipitate, dispersing the precipitate in deionized water, and dialyzing for 24 hours to remove unreacted modifier B to obtain a QDs/A/B quantum dot aqueous solution;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/A/B quantum dot aqueous solution obtained in the step 1), diluting the quantum dots, and adjusting the pH value of the solution to 6.0-10.0 by using a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink;
the oil-soluble quantum dots are selected from core-shell quantum dots CdSe/ZnS, CdSe/CdS/ZnS and alloy quantum dots Cd x Zn 1–x S、CdSe/Cd x Zn 1–x One of S, wherein x is more than 0 and less than 1, and the surface ligand of the quantum dot is one or two of tri-n-octyl phosphine oxide, tri-n-octyl phosphine, tributylphosphine, 1-octadecene, oleylamine and oleic acid;
step 1) the hydrophilic modifier A is selected from one of thioglycolic acid, mercaptopropionic acid, mercaptobutyric acid, mercaptobenzoic acid, mercaptoundecanoic acid and dimercaptosuccinic acid, the concentration of the aqueous solution of the hydrophilic modifier A is 1-10mM, and the molar ratio of the hydrophilic modifier A to the oil-soluble quantum dots is 100-1000: 1;
the mol ratio of the modifier B to the modifier A in the step 1) is 0.2-5: 1, the modifier B is one of branched polyethyleneimine, polyamidoamine, octadecylamine polyoxyethylene ether and dodecylamine polyoxyethylene ether.
2. The ultra-stable printable aqueous fluorescent anti-counterfeiting ink according to claim 1, wherein the organic solvent used in the organic solution of the oil-soluble quantum dots is n-hexane or chloroform, and the concentration of the quantum dots is 10-100 μ M.
3. The ultra-stable printable aqueous fluorescent anti-counterfeiting ink according to claim 1, wherein a catalyst is further added to the mixed solution in the step 1), and the catalyst is N, N' -dicyclohexylcarbodiimide and N-hydroxysuccinimide.
4. The ultra-stable printable aqueous fluorescent anti-counterfeiting ink according to claim 1, wherein the concentration of the quantum dots in the aqueous fluorescent anti-counterfeiting ink in the step 2) is 1-10 μ M, and the volume ratio of the water to the ethanol to the glycol is 5-8: 1-2: 1-3.
5. A method for preparing the ultrastable printable aqueous fluorescent anti-counterfeiting ink according to any one of claims 1 to 4, which is characterized by comprising the following steps:
1) preparing a quantum dot aqueous solution: dissolving a hydrophilic modifier A in water to obtain a hydrophilic modifier A aqueous solution, adding the hydrophilic modifier A aqueous solution into an organic solution of oil-soluble quantum dots, carrying out ultrasonic treatment on the obtained mixed solution for 2-4 hours, standing, taking out an aqueous solution layer containing QDs/A quantum dots after the mixed solution is layered, gradually dropwise adding a modifier B aqueous solution into the QDs/A quantum dot aqueous solution, then placing the obtained mixed solution into a water bath constant-temperature oscillator for 24 hours of room-temperature and light-resistant oscillation, centrifuging the obtained reaction solution, collecting supernatant, centrifuging, collecting precipitate, dispersing the precipitate in deionized water, and dialyzing for 24 hours to remove the unreacted modifier B to obtain a QDs/A/B quantum dot aqueous solution;
2) preparing water-based fluorescent anti-counterfeiting ink: adding water, ethanol and glycol into the QDs/A/B quantum dot aqueous solution obtained in the step 1), diluting the quantum dots, and adjusting the pH value of the solution to 6.0-10.0 by using a pH regulator to obtain the aqueous fluorescent anti-counterfeiting ink.
6. Use of the ultra-stable printable aqueous fluorescent security ink according to any one of claims 1 to 4, wherein the aqueous fluorescent security ink is directly added to a cartridge of a conventional inkjet printer, and the security pattern is printed on a substrate material.
7. Use of the ultra-stable printable aqueous fluorescent anti-counterfeiting ink according to any one of claims 1 to 4 for product anti-counterfeiting, document protection and information encryption.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011281379.XA CN112175449B (en) | 2020-11-16 | 2020-11-16 | Super-stable printable aqueous fluorescent anti-counterfeiting ink and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011281379.XA CN112175449B (en) | 2020-11-16 | 2020-11-16 | Super-stable printable aqueous fluorescent anti-counterfeiting ink and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112175449A CN112175449A (en) | 2021-01-05 |
| CN112175449B true CN112175449B (en) | 2022-08-26 |
Family
ID=73918552
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011281379.XA Active CN112175449B (en) | 2020-11-16 | 2020-11-16 | Super-stable printable aqueous fluorescent anti-counterfeiting ink and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112175449B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113174252B (en) * | 2021-04-30 | 2023-02-14 | 华中科技大学 | CdSe quantum dot and photoluminescence regulation and control method and application thereof |
| CN115044251B (en) * | 2022-03-11 | 2023-09-29 | 东南大学 | Multicolor fluorescent ink based on light-operated nano particles and preparation method thereof |
| CN117304743B (en) * | 2023-08-14 | 2024-04-09 | 杭州师范大学 | Bimodal information storage anti-counterfeiting material and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB0813273D0 (en) * | 2008-07-19 | 2008-08-27 | Nanoco Technologies Ltd | Method for producing aqueous compatible nanoparticles |
-
2020
- 2020-11-16 CN CN202011281379.XA patent/CN112175449B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112175449A (en) | 2021-01-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112175449B (en) | Super-stable printable aqueous fluorescent anti-counterfeiting ink and preparation method thereof | |
| Kumar et al. | Future prospects of luminescent nanomaterial based security inks: from synthesis to anti-counterfeiting applications | |
| Abdollahi et al. | Photoluminescent and chromic nanomaterials for anticounterfeiting technologies: recent advances and future challenges | |
| Park et al. | Color tunable carbon quantum dots from wasted paper by different solvents for anti-counterfeiting and fluorescent flexible film | |
| KR101167733B1 (en) | Dispersant for nanoparticles having surfaces to which capping-ligands are bound, Method for dispersing the nanoparticles using the same and Nanoparticle thin film comprising the same | |
| Kim et al. | Color-coded multilayer photopatterned microstructures using lanthanide (III) ion co-doped NaYF4 nanoparticles with upconversion luminescence for possible applications in security | |
| Fu et al. | Color-switchable hybrid dots/hydroxyethyl cellulose ink for anti-counterfeiting applications | |
| US6576155B1 (en) | Fluorescent ink compositions comprising functionalized fluorescent nanocrystals | |
| Sun et al. | pH-guided self-assembly of silver nanoclusters with aggregation-induced emission for rewritable fluorescent platform and white light emitting diode application | |
| Manhat et al. | One-step melt synthesis of water-soluble, photoluminescent, surface-oxidized silicon nanoparticles for cellular imaging applications | |
| Deng et al. | Facile synthesis of high‐quality, water‐soluble, near‐infrared‐emitting PbS quantum dots | |
| Han et al. | Colloidal stable quantum dots modified by dual functional group polymers for inkjet printing | |
| CN111788279B (en) | Method for producing luminescent particle, and biological imaging material | |
| CN104031477A (en) | Panchromatic fluorescent anti-counterfeiting ink based on conjugated polymer nano-particles | |
| Wang et al. | Application in anticounterfeiting for multistimuli smart luminescent materials based on MOF-on-MOF | |
| Ngoensawat et al. | Luminescent nanohybrid of ZnO quantum dot and cellulose nanocrystal as anti-counterfeiting ink | |
| Song et al. | Synthesis and inkjet printing of NaYF4: Ln3+@ NaYF4 core–shell nanoparticles with enhanced upconversion fluorescence for anti-counterfeiting applications | |
| CN101308061B (en) | Rapid latent fingerprint presentation reagent preparation method | |
| Kar et al. | Highly water-stable, luminescent, and monodisperse polymer-coated CsPbBr 3 nanocrystals for imaging in living cells with better sensitivity | |
| Chao et al. | Enhanced aggregation-induced phosphorescence of carbon dots for information encryption applications | |
| Xie et al. | Water-borne, durable and multicolor silicon nanoparticles/sodium alginate inks for anticounterfeiting applications | |
| CN110591450B (en) | Dual-mode luminous water-based anti-counterfeiting ink, and preparation method and application thereof | |
| Yu et al. | Highly stabile ZnGa2O4: Eu nanocrystals as a fluorescence probe for bio-imaging | |
| CN111704828B (en) | Encryption ink, anti-counterfeiting encryption method, multiple encryption system and application | |
| Zhang et al. | One-pot synthesis of stable water soluble Mn: ZnSe/ZnS core/shell quantum dots |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |