8-hydroxyquinoline aluminum-nano-silver-acrylate hybrid emulsion for rapidly detecting trace halogen in water-based ink and detection method of 8-hydroxyquinoline aluminum-nano-silver-acrylate hybrid emulsion

Abstract

The invention belongs to the technical field of water-based ink, and particularly relates to an aluminum 8-hydroxyquinoline-nano-silver-acrylate hybrid emulsion for rapidly detecting trace halogen in water-based ink and a detection method of the aluminum 8-hydroxyquinoline-nano-silver-acrylate hybrid emulsion, and the aluminum 8-hydroxyquinoline-nano-silver-acrylate hybrid emulsion comprises the following steps: grafting aluminum 8-hydroxyquinoline and nano-silver particles by taking an acrylate emulsion as a skeleton; the hybrid emulsion has no fluorescence reaction in a normal state, and shows fluorescence after a halogen ion-containing substance is added; the preparation method comprises the following steps: uniformly dispersing 8-hydroxyquinoline aluminum, nano-silver particles and the like to obtain a pre-dispersion liquid; dispersing deionized water, an acrylate monomer and the like at a high speed to obtain a seed emulsion; and dropwise adding the pre-dispersion liquid into the seed emulsion, and polymerizing to obtain the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion. The method can be used for quickly and qualitatively judging the residual halogen ions in the coloring agent or the color paste in the water-based ink through a macroscopic fluorescence phenomenon. The method is convenient and efficient, has no extra detection cost, and is suitable for rapid quality inspection and early warning of vast water-based ink factories.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water-based inks, and particularly relates to an 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapidly detecting trace halogens in water-based inks and a detection method thereof. BACKGROUND

[0002] Halogen and halogen compounds are often used as flame retardant additives in chemicals, and are made into electronic and electrical housings, building coatings and coating materials, textiles, toys, etc. with flame retardant function. Excessive use of halogen has brought harm to human life. Chlorinated flame retardants release chlorine gas during disposal or incineration, which is highly toxic to the human body and directly affects the respiratory system. After the waste of electronic and electrical products, textiles, building materials, etc. is incinerated, brominated flame retardants in the waste will form dioxins, which have high toxicity, high migration and persistent pollution to the environment and human beings. Therefore, the world is currently paying close attention to the restriction and control of halogen and compounds, and various restriction standards have been issued. China implements green packaging policy, encourages the use of degradable and harmless materials, and reduces the impact of packaging waste on the environment. In this context, halogen-free water-based inks for packaging printing are highly valued.

[0003] The synthesis of organic pigments involves the use of halogen-containing compounds such as hydrochloric acid in the synthesis and pickling process, which can easily leave halogen residues in the finished pigments. In terms of halogen analysis, energy dispersive X-ray spectrometer (EDX) can simultaneously detect F, Cl, Br and I with one sample, which is currently the necessary means for halogen-free detection. However, this device is expensive, and as a professional instrument, not every ink factory has the condition to purchase EDX to detect halogen residues in each batch of ink. Therefore, it is necessary to develop a low-cost solution that can conveniently detect halogen residues.

[0004] The term "trace" is a relative concept in analytical science, and its specific threshold depends on the material system being analyzed and industry standards. In the electronics industry, it may refer to ppb levels; but in the field of polymer chemistry and ink industry, due to the complexity of the system and the presence of many interfering substances, the detection of inorganic ion residues at the level of hundreds of ppm (such as zero point zero percent) is usually considered by those skilled in the art as belonging to the category of "trace analysis".

[0005] 8-hydroxyquinoline aluminum (CAS: 2085-33-8, referred to as Alq3) is a stable complex of 8-hydroxyquinoline and aluminum under alkaline conditions, insoluble in water, but can be extracted and dissolved by organic solvents, is a key material in organic electroluminescent devices, widely used in light-emitting materials and electron transport materials, etc. In the semiconductor industry. Under the 365 nm wavelength ultraviolet lamp, a very small amount can be seen with the naked eye Alq3 shows bright fluorescence, the reaction is very sensitive (Tian Qiren, Application of nano-silver-8-hydroxyquinoline aluminum quenching system in fingerprint development, Guangdong Chemical Industry, 2015). Under appropriate environmental conditions, there are the following fluorescence color development and quenching reactions: Alq3 in solution exists fluorescence reaction→add appropriate amount of nano-silver to the solution, the fluorescence is quenched→add sodium chloride to the solution of Alq3 and nano-silver system, the fluorescence reappears.

[0006] The principle is to add nano-silver to the Alq3 solution. The electromagnetic waves emitted by a fluorescent molecule will be absorbed and scattered by multiple silver nanoparticles in the solution. Nano-silver absorbs the electromagnetic waves emitted by Alq3. This loss not only weakens the intensity of the incident electromagnetic field at the particle surface, but also absorbs the electromagnetic waves radiated by the fluorescent group, thereby causing overall fluorescence attenuation. Because silver nanoparticles have a large absorption and scattering cross-section, a large part of the electromagnetic wave will be consumed in the propagation process, and cannot be accepted by the detector, and ultimately leads to fluorescence quenching. However, when halogen ions such as chlorine and bromine are added, halogen ions form chemical adsorption with nano-silver, thereby weakening the interaction between nano-silver and Alq3, ultimately leading to fluorescence enhancement of the quenching system.

[0007] Using this principle, Alq3 and nano-silver are grafted into acrylic ester latex particles in an appropriate ratio and suitable way to synthesize Alq3-nano-silver-acrylate hybrid emulsion (referred to as AAP emulsion) in a fluorescence quenching state. The halogen in the water-based ink mainly comes from the pigment colorant. When the ink factory uses a colorant containing halogen, and mixes with the water-based resin to prepare water-based ink, only the liquid ink needs to be irradiated with a ultraviolet lamp to quickly determine whether it contains halogen: if the fluorescence reaction is obvious, the colorant in the water-based ink contains halogen; if there is no fluorescence reaction, the colorant in the water-based ink does not contain halogen; greatly facilitates the daily qualitative control work of halogen for ink manufacturers.

[0008] The aluminum quinolinol-silver nanoparticle composite system is used for testing and measuring sodium chloride (i.e. salt in fingerprints) in the field of criminal investigation. In addition to halogen ions such as chlorine, theoretically, anions such as S2- and CN- can also form more stable precipitates (such as Ag2S and AgCN) with silver nanoparticles, thereby causing fluorescence recovery. However, these interfering ions are extremely unlikely to exist in the colorant (organic pigment) of water-based ink. The production process and chemical composition of commercial organic pigments generally do not contain sulfides, cyanides and other strong interfering anions. These substances are toxic and unstable by themselves, and are incompatible with the production system of pigments. It is also almost impossible for other components (such as additives, water) of water-based ink to contain these ions.

[0009] However, neither Alq3 nor silver nanoparticles are soluble in water (Li Jiuyu, Determination of Soluble Aluminum in Acidic Soil by 8-Hydroxyquinoline (pH 8.3) Spectrophotometry, Soil, 2004). Moreover, Alq3 in aqueous solution is unstable and will change from light yellow to brown or even black after one week of standing (Jia Mengxin, Research Progress on Preparation and Application of Aluminum 8-Hydroxyquinoline, Guangzhou Chemical Industry, 2013). Therefore, how to graft these two substances into water-based resin and maintain storage stability is a problem that still needs to be solved. SUMMARY

[0010] The purpose of the present application is to solve the problem in the prior art that it is not possible to qualitatively detect trace amounts of halogen ions with a content of less than 1000 ppm, especially as low as 100-200 ppm, in water-based ink at low cost and high efficiency, and to maintain the storage stability of the substance.

[0011] In order to achieve the above-mentioned purpose, the present application provides an 8-hydroxyquinoline aluminum-silver nanoparticle-acrylate hybrid emulsion for rapid detection of trace amounts of halogen in water-based ink, comprising: The acrylate emulsion is used as the skeleton, and 8-hydroxyquinoline aluminum and silver nanoparticles are grafted. The 8-hydroxyquinoline aluminum-silver nanoparticle-acrylate hybrid emulsion has no fluorescence reaction under normal conditions, and shows fluorescence after the addition of a substance containing halogen ions. The preparation method of the 8-hydroxyquinoline aluminum-silver nanoparticle-acrylate hybrid emulsion comprises the following steps: S1. Deionized water, defoaming agent, solvent, emulsifier, coupling agent, initiator, 8-hydroxyquinoline aluminum and silver nanoparticles are mixed and uniformly dispersed to prepare an 8-hydroxyquinoline aluminum-silver nanoparticle pre-dispersion with a particle size D90<1 μm; The purity of the 8-hydroxyquinoline aluminum is ≥95%, the iron content is ≤0.001%, the chloride content is ≤0.002%, the sulfate content is ≤0.1%, the ammonium salt content is ≤0.005%, the free aluminum content is ≤0.5%, and the heavy metal content calculated as Pb is ≤0.001%. The original particle size of the nano-silver particles is 10-100 nm, D50 < 50 nm, D90 < 80 nm, the polydispersity index PDI < 0.2; the purity > 99.2%; the Zeta potential absolute value of the nano-silver particles in the aqueous solution > 30 mV; and the specific surface area of the nano-silver particles is 20-100 m² / g; S2. Deionized water, emulsifier, pH buffer, and acrylate monomer are uniformly dispersed at high speed to prepare a seed emulsion; S3. The 8-hydroxyquinoline aluminum-nano silver pre-dispersion liquid is added dropwise into the seed emulsion, and emulsion polymerization is carried out in a polymerization device to obtain an 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion.

[0012] Preferably, the mass percentage of the deionized water in S1 is 76%-92%; the mass percentage of the defoaming agent is 0.1%-1%; the mass percentage of the solvent is 5%-10%; the mass percentage of the emulsifier is 1%-3%; the mass percentage of the coupling agent is 1%-3%; the mass percentage of the initiator is 0.5%-5%; the mass percentage of 8-hydroxyquinoline aluminum is 0.01%-1%; and the mass percentage of the nano-silver particles is 0.01%-1%.

[0013] Preferably, the mass percentage of the deionized water in S2 is 40%-60%, the mass percentage of the emulsifier is 1%-3%, the mass percentage of the pH buffer is 0.1%-1%, and the mass percentage of the acrylate monomer is 30%-60%.

[0014] Preferably, the solvent in S1 refers to one or more of ethanol, isopropyl alcohol, n-propanol, propylene glycol methyl ether, propylene glycol butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, propylene glycol phenyl ether, methyl acetate, isobutyl acetate, amyl acetate, ethyl lactate, divalent acid ester, butyrolactone, 1-methyl-2-pyrrolidone, isofuroline, dimethyl sulfoxide, and tetrahydrofuran; the coupling agent refers to one or more of 3-aminopropyl triethoxysilane, 3-aminopropyl methyldiethoxysilane, N,N-diethyl-3-aminopropyl trimethoxysilane, bis-(3-trimethoxysilylpropyl) amine, anilinomethyl triethoxysilane, diethylaminomethyl triethoxysilane, 3-glycidyl ether propyl trimethoxysilane, 3-ureidopropyl trimethoxysilane, and 3-ureidopropyl triethoxysilane; and the initiator refers to one or more of ammonium persulfate, potassium persulfate, benzoyl peroxide, di-tert-butyl peroxide, azobis isobutyronitrile, and dilauroyl peroxide.

[0015] Preferably, the emulsifier in S1 and S2 refers to one or more of sodium salt of heavy alkyl benzene sulfonate, sodium lauryl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium ethyl sulfonate, sodium succinic anhydride-3-sulfonate, disodium lauryl alcohol polyether sulfosuccinate, sodium methyl stearate sulfonate, nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether M, nonylphenol polyoxyethylene ether sulfate ammonium salt, polyethylene glycol, polyoxyethylene lauryl alcohol ether, sorbitan tristearate, pentaerythritol tetraisostearate.

[0016] Preferably, the acrylate monomer in S2 refers to one or more of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, t-butyl acrylate, t-butyl methacrylate, isooctyl acrylate, isooctyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate; the seed emulsion S2 also includes acrylic acid or methacrylic acid.

[0017] Preferably, the polymerization device in S3 is an acrylate emulsion reactor with nitrogen protection device and temperature control device.

[0018] The application also provides a method for rapid detection of trace halogen in water-based ink prepared by using the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion.

[0019] Preferably, the method comprises the following steps: S1, weigh the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion prepared in claim 1 and place it under ultraviolet lamp observation: under normal conditions, the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion has no fluorescent reaction, and after adding salt, obvious fluorescent phenomenon is observed, indicating that the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion is qualified; if the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion has fluorescent reaction under ultraviolet lamp without adding salt or cannot observe fluorescent reaction after adding salt, it is judged as unqualified product. S2. Pour the qualified 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion in S1 into a cylinder and add solvent, defoaming agent, leveling agent, neutralizing agent, wear-resistant agent, and water-based color paste in sequence, disperse uniformly, filter, and obtain water-based ink. S3. Weigh the water-based ink, place it in a beaker, and observe under ultraviolet lamp: if there is no fluorescent phenomenon, the water-based ink does not contain halogen; if there is fluorescent phenomenon, the water-based ink contains halogen.

[0020] Preferably, the table salt in S1 is iodine-free edible salt; the ultraviolet lamp in S1 and S3 is an ultraviolet light generating device capable of emitting 100-200 nm UVD waveband, 200-275 nm UVC waveband, 275-320 nm UVB waveband, and 320-400 nm UVA waveband.

[0021] Compared with the prior art, the present application has the following advantages: Firstly, the emulsifier and coupling agent are used to mix and disperse them uniformly, the coupling agent can coat the surface of the 8-hydroxyquinoline aluminum and nano silver particles, thereby providing conditions for grafting reaction, and then the emulsifier is used to realize stable dispersion in their aqueous solution, the alkoxyl group (such as -Si(OCH3)3) at one end of the silane coupling agent is hydrolyzed to form silanol (-Si-OH), which can form a firm covalent bond (Si-O-base material) with the hydroxyl group (-OH) on the surface of the 8-hydroxyquinoline aluminum and nano silver particles, and the organic functional group (such as a double bond) at the other end participates in emulsion polymerization to form chemical combination with the polymer chain, thereby synthesizing 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion. The prepared hybrid emulsion is used to prepare water-based ink, and the residual halogen ions in the colorant or color paste in the water-based ink can be quickly qualitatively judged through the visible fluorescence phenomenon. Compared with the EDX spectrometer test method, the method is not only convenient and efficient, but also has no additional detection cost, and is suitable for rapid quality inspection and early warning of the majority of water-based ink manufacturers. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 Fig. 2 is a fluorescence intensity comparison chart of water-based inks A-1, A-2, B-1, B-2, C-1 and C-2 in the embodiment of the present application under D65 lamp tubes and UV lamp tubes, respectively. Figure 2 Fig. 3 is a fluorescence intensity comparison chart of water-based inks D-1, D-2, E-1, E-2, F-1 and F-2 in the embodiment of the present application under D65 lamp tubes and UV lamp tubes, respectively. DETAILED DESCRIPTION

[0023] The terms used in the present application have the meanings generally understood by those of ordinary skill in the art, unless otherwise specified.

[0024] In the following examples, various processes and methods not described in detail are conventional methods known in the art.

[0025] The reagents used in the following examples are commercially available, and the experimental operations and experimental conditions not mentioned are referred to conventional operations and conventional conditions in the art.

[0026] The specific embodiments of the present application are illustrated in the following examples.

[0027] Example 1 Step 1: Under stirring, add the raw materials listed in the table below sequentially into a 250 ml glass beaker. Simultaneously, set the emulsifier to 2000 rpm and disperse evenly for 1 hour until no obvious particles or flocculated matter are visible to the naked eye. Then, add commercially available 8-hydroxyquinoline aluminum and commercially available nano-silver particles, and continue high-speed emulsification for 1 hour until the particle size D90 measured by a laser particle size analyzer (Zhuhai Zhenli LT2200) is 0.85 μm, as shown in Table 1.

[0028] Table 1

[0029] Step 2: Add the following raw materials in sequence to a 2000ml glass beaker while dispersing them, and rotate at 500rpm for 1 hour until a milky white and homogeneous solution is obtained, thus preparing the seed emulsion, as shown in Table 2.

[0030] Table 2

[0031] Step 3: Pour the seed emulsion from Step 2 into a glass reactor, stirring and heating continuously until the set temperature of 80°C is reached. o After maintaining a constant temperature at 85°C, nitrogen gas was introduced to purge oxygen. Then, the pre-dispersion of 8-hydroxyquinoline aluminum-silver nanoparticles prepared in the first step was slowly added dropwise to the seed emulsion, with the temperature controlled at 85°C. o The polymerization was carried out at a constant temperature of 25°C for 4.5 hours; after the reaction was completed, the mixture was allowed to cool naturally to 25°C. o C. Then, filter the emulsion through a 120 mesh screen to obtain AAP emulsion, and perform quality inspection. The measured emulsion parameters are shown in Table 3 below: Table 3

[0032] Step 4: Pour the qualified AAP emulsion from Step 3 into a glass beaker, and while dispersing, add the following raw materials in sequence. After even dispersion, water-based inks A-1, A-2, B-1, B-2, C-1, and C-2 are obtained (all color pastes used are provided by Guangdong Kedi, with a pigment content of 40%; the halogen content in the color pastes is tested using an X-ray fluorescence spectrometer, Tianrui EDX1800). Weigh 50g of the water-based ink to be tested into a glass beaker and place it in a standard light source colorimetric box. Turn on the D65 lamp (international standard artificial daylight) and the UV lamp (wavelength 365nm) in sequence. For details on the fluorescence intensity of the water-based ink, see [link to relevant documentation]. Figure 1 .

[0033] Table 4

[0034] like Figure 1As shown, after adding salt, there is no visible difference between inks formulated with a conventional emulsion system and those formulated with an AAP emulsion system under a D65 light source. However, under a UV light source, the inks containing halogen pigments (pigment green 36, pigment blue 15:3) show a significant fluorescence reaction in the AAP emulsion system, while the inks formulated with the conventional emulsion system show no fluorescence reaction. For the inks without halogen pigments (pigment red 122), neither emulsion system shows a fluorescence reaction. This demonstrates that using Example 1 of this patent allows for a qualitative assessment of the halogen content in inks, with significant results.

[0035] Example 2 Step 1: While stirring, add the raw materials listed in the table below to a 250ml glass beaker in sequence. Simultaneously, set the emulsifier to 2000rpm and disperse evenly for 1 hour until no obvious particles or flocculated matter are visible to the naked eye. Then, add commercially available 8-hydroxyquinoline aluminum and commercially available nano silver particles, and continue high-speed emulsification for 1 hour until the particle size D90 measured by a laser particle size analyzer (Zhuhai Zhenli LT2200) is 0.65μm. The specific formula is shown in Table 5.

[0036] Table 5

[0037] Step 2: Add the following raw materials in sequence to a 2000ml glass beaker while dispersing them, and rotate at 500rpm for 1 hour until a milky white and homogeneous solution is obtained, thus preparing the seed emulsion, as shown in Table 6.

[0038] Table 6

[0039] Step 3: Pour the seed emulsion from Step 2 into a glass reactor, stirring and heating continuously until the set temperature of 80°C is reached. o After maintaining a constant temperature at 87°C, nitrogen gas was introduced to purge oxygen; then, the pre-dispersion of Alq3-silver nanoparticles prepared in the first step was slowly added dropwise to the seed emulsion, with the temperature controlled at 87°C. o The polymerization was carried out at a constant temperature of 25°C for 5.0 hours; after the reaction was completed, the mixture was allowed to cool naturally to 25°C. o C. Then, filter the emulsion through a 120 mesh screen to obtain AAP emulsion, and perform quality inspection. The measured emulsion parameters are shown in Table 7 below: Table 7

[0040] Fourth step: pour the qualified AAP emulsion in step three into a glass beaker, add the following raw materials in turn while dispersing, and prepare water-based inks D-1, D-2, E-1, E-2, F-1, F-2 (the color paste used is provided by Guangdong Kedi, and the pigment content is 40%; the halogen content in the color paste is tested by X-ray fluorescence spectrometer, Tianrui EDX1800). Then, weigh 50 g of the water-based ink to be tested into a glass beaker, and place it in a standard light source colorimetric light box. Turn on the D65 lamp tube (international standard artificial daylight) and the UV lamp tube (wavelength 365 nm) in turn, and the fluorescence intensity of the water-based ink is shown in Table 8. Figure 2 .

[0041] Table 8

[0042] As shown in Figure 1 , there is no difference between the water ink prepared by the conventional emulsion system and the water ink prepared by the AAP emulsion system under the naked eye after adding salt under the D65 light source; however, under the UV light source, the water ink containing halogen pigment system (pigment yellow 110, pigment blue 15:0) has a fluorescent reaction under the AAP emulsion system, while the water ink prepared by the conventional emulsion system has no fluorescent reaction; the water ink without halogen pigment system (pigment yellow 74) has no fluorescent reaction under the two emulsion systems. It is proved that the method of the present application can qualitatively judge the halogen content in the water ink, and the effect is obvious. For as low as 180 ppm of halogen residue, the method of the present application still gives a clear and visible positive fluorescent reaction (see Example 1, B-2 formula), and the detection sensitivity of the method covers the "trace" level of hundreds of ppm.

[0043] The commercial leveling agent (Digo 240) added in Example 1 and Example 2 is one of the types of surfactants, which is a non-ionic silicone wetting agent; the commercial biological defoaming agent (Digo 825) and the wear-resistant agent (MD2000) are emulsion systems of modified silicone oil and small molecular weight polyethylene, respectively. In order to improve the compatibility of the systems, non-ionic surfactants such as Tween and Span are mainly used as emulsifiers, and almost no anionic emulsifiers are used; the commercial water-based color paste selects the resin-free color provided by Guangdong Kedi, and the dispersant also selects the non-ionic type, which can avoid the interference of irrelevant ions as much as possible.

[0044] From the experimental results of Example 1 and Example 2, it can be seen that by emulsion polymerization, 8-hydroxyquinoline aluminum and nano-silver particles are grafted into the acrylate emulsion, the synthesized AAP emulsion solves the problems of stratification and precipitation of 8-hydroxyquinoline aluminum and nano-silver, and also solves the problem of oxidation blackening of 8-hydroxyquinoline aluminum aqueous solution due to the excellent coating of the grafted polymer on 8-hydroxyquinoline aluminum. The water-based ink prepared by the emulsion can destroy the stable state of 8-hydroxyquinoline aluminum and nano-silver through trace halogen in the pigment, and then use the sensitive fluorescence activation effect of 8-hydroxyquinoline aluminum, and cooperate with UV light source, so that the presence of halogen can be qualitatively judged by whether there is a fluorescence reaction, which ingeniously solves the problem of low-cost and high-efficiency detection of trace halogen in water-based ink.

[0045] The phenomenon that the fluorescence intensity of B-2 is higher than that of E-2 is the result of the combined action of multiple factors such as the existence form of halogen, ion release, and Alq3 / nano-silver ratio optimization. The fluorescence intensity not only depends on the total amount of halogen, but also is related to the halogen ion species, existence form and reaction environment; the difference in halogen ion species: B-2 uses pigment blue 15:3, and the halogen mainly comes from the residual synthesis solvent (such as chloroform, dichloromethane, etc.), existing in the form of free or easily released chloride ions (Cl⁻), which is more likely to react with nano-silver, resulting in obvious fluorescence recovery. The halogen in E-2 uses pigment blue 15:0, although the total amount is slightly higher (267 ppm), but it may exist in the form of structural bonding or complexation, and the ability to release halogen ions is weak, resulting in less obvious fluorescence reaction than B-2. Ion release and reaction activity: different pigment synthesis processes have significant differences in the existence form and release rate of halogen, which directly affects the reaction efficiency with nano-silver. Even if the total amount of halogen is high, if it is difficult to release in the form of ions in a short time, the fluorescence reaction will be weak. The surface area and dispersity of nano-silver: the specific surface area, particle size distribution (D90) and Zeta potential of nano-silver also affect its adsorption efficiency with halogen ions. The dispersity of nano-silver in Example 1 is better (D90=0.85 μm), which further enhances the reaction activity.

[0046] Under a specific 365 nm ultraviolet lamp, qualitative judgment (with / without fluorescence) by direct observation with the naked eye is a highly sensitive and intuitive on-site rapid detection method. Figure 1 、 Figure 2For the phenomenon of the sample under the UV lamp in the dark room environment using the mobile phone camera. It is known that when shooting weak light sources such as fluorescence, the mobile phone camera will automatically perform a series of algorithm optimizations to improve the brightness and clarity of the picture, including but not limited to: automatic exposure adjustment → the camera will automatically increase the brightness of the overall picture, which may cause the originally weak fluorescence to appear brighter in the photo than actually seen by the naked eye; automatic white balance → the camera may adjust the color temperature, so that the color rendering effect of different batches and different color phases (such as blue light and yellow-green light) of fluorescence in the picture deviates from the real visual experience; noise reduction and sharpening → the algorithm will remove some noise and enhance the edges, which may change the shape and visual intensity of the fluorescence emitting area. Figure 1 , Figure 2 The "B-2 fluorescence effect is stronger than E-2" presented in the above is a relative, camera algorithm processed visual contrast, which is mainly used to assist in explaining the qualitative conclusion of "with" and "without" fluorescence. In actual visual observation, the judgment of the human eye on the "obvious" or "weak" fluorescence is based on the direct comparison under the same standard light source on site, which has higher sensitivity and accuracy than the camera shooting result.

[0047] The core of the present application for qualitative detection of trace halogen in water-based ink is the reaction of nano-silver particles and halogen ions. This reaction is a surface reaction, and its essence is to form silver halide or strong adsorption. Even if the halogen ion concentration of the whole system is low (such as 180 ppm), in the local microenvironment of the surface of nano-silver particles, halogen ions can be enriched due to electrostatic attraction and high surface energy, thereby achieving a "local high concentration" sufficient to trigger obvious chemical changes. This surface reaction is very sensitive, and a small amount of halogen ions is enough to change the chemical state of the surface of nano-silver particles. Moreover, the fluorescence change in the present application is a "quenching-recovery" switching process, rather than a linear gradual change process, which has a signal amplification effect. The fluorescence of Alq3 is quenched (off state) by nano-silver through a non-radiative energy transfer mechanism. The intervention of halogen ions, even in a small amount, is enough to partially destroy this energy transfer mechanism. As long as a certain number of nano-silver particles are "passivated" by halogen ions, their quenching ability will be weakened, and the fluorescence of Alq3 will be released (on state). The human eye is very sensitive to fluorescence under 365 nm ultraviolet light, and weak fluorescence enhancement can be clearly recognized by the naked eye. Therefore, the detection method provided by the present application can realize qualitative judgment without complete "effective adsorption".

[0048] The above is a detailed description of the embodiments, which facilitates the correct understanding and use of the present application by those skilled in the art. Any improvement or modification technical solution obtained by those skilled in the art on the basis of the prior art without innovative labor, only through analysis, analogy or limited enumeration, etc. should be within the protection scope determined by the claims.

Claims

1. An 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks, characterized in that, include: Using acrylate emulsion as a framework, 8-hydroxyquinoline aluminum and silver nanoparticles were grafted onto it. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion does not exhibit fluorescence under normal conditions, but shows fluorescence after the addition of a substance containing halide ions. The preparation method of the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion includes the following steps: S1. Deionized water, defoamer, solvent, emulsifier, coupling agent, initiator, 8-hydroxyquinoline aluminum, and silver nanoparticles are mixed and dispersed evenly to prepare an 8-hydroxyquinoline aluminum-silver nanoparticle pre-dispersion with a particle size D90 < 1 μm. The 8-hydroxyquinoline aluminum has a purity ≥95%, iron content ≤0.001%, chloride content ≤0.002%, sulfate content ≤0.1%, ammonium salt content ≤0.005%, free aluminum content ≤0.5%, and heavy metal content (based on Pb) ≤0.001%. The original particle size of the silver nanoparticles is 10-100 nm, D50 < 50 nm, D90 < 80 nm, polydispersity index (PDI) < 0.2; purity > 99.2%; absolute value of zeta potential of the silver nanoparticles in aqueous solution > 30 mV; specific surface area of ​​the silver nanoparticles is 20-100 m² / g. S2. Deionized water, emulsifier, pH buffer, and acrylate monomer are dispersed at high speed and uniformly to prepare a seed emulsion; S3. Add the 8-hydroxyquinoline aluminum-nano silver pre-dispersion dropwise to the seed emulsion and carry out emulsion polymerization in a polymerization device to obtain an 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion.

2. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks as described in claim 1, characterized in that, In S1, the mass percentage of deionized water is 76%~92%; the mass percentage of defoamer is 0.1%-1%; the mass percentage of solvent is 5%-10%; the mass percentage of emulsifier is 1%-3%; the mass percentage of coupling agent is 1%-3%; the mass percentage of initiator is 0.5%~5%; the mass percentage of 8-hydroxyquinoline aluminum is 0.01%-1%; and the mass percentage of nano-silver particles is 0.01%-1%.

3. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks as described in claim 1, characterized in that, The S2 contains 40%-60% deionized water, 1%-3% emulsifier, 0.1%-1% pH buffer, and 30%-60% acrylate monomer.

4. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks as described in claim 1, characterized in that, The solvent in S1 refers to one or more of the following: ethanol, isopropanol, n-propanol, propylene glycol methyl ether, propylene glycol butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, propylene glycol phenyl ether, methyl acetate, isobutyl acetate, amyl acetate, ethyl lactate, divalent esters, butyrolactone, 1-methyl-2-pyrrolidone, isoflurane, dimethyl sulfoxide, and tetrahydrofuran; the coupling agent refers to 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, etc. N,N-Diethyl-3-aminopropyltrimethoxysilane, bis-(3-trimethoxysilylpropyl)amine, anilinemethyltriethoxysilane, diethylaminomethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-ureapropyltrimethoxysilane, and 3-ureapropyltriethoxysilane are one or more of the following: the initiator is ammonium persulfate, potassium persulfate, benzoyl peroxide, di-tert-butyl hydroperoxide, azobisisobutyronitrile, and dilauryl peroxide are one or more of the following:

5. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks as described in claim 1, characterized in that, The emulsifiers in S1 and S2 refer to one or more of the following: sodium heavy alkylbenzene sulfonate, sodium dodecyl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium ethyl thiosulfate, sodium succinic anhydride-3-sulfonate, disodium lauryl ether sulfosuccinate, sodium methyl stearate sulfonate, nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether M, nonylphenol polyoxyethylene ether ammonium sulfate, polyethylene glycol, polyoxyethylene lauryl ether, sorbitan tristearate, and pentaerythritol tetraisostearate.

6. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks as described in claim 1, characterized in that, The acrylate monomers in S2 refer to one or more of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, isooctyl acrylate, isooctyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate; the seed emulsion in S2 also includes acrylic acid or methacrylic acid.

7. The 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion for rapid detection of trace halogens in water-based inks as described in claim 1, characterized in that, The polymerization device in S3 is an acrylic emulsion reactor equipped with a nitrogen protection device and a temperature control device.

8. A rapid detection method for trace halogens in water-based inks prepared using the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion as described in claim 1, characterized in that, Includes the following steps: S1. Weigh the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion prepared according to claim 1 and observe it under a UV lamp: Under normal conditions, the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion shows no fluorescence reaction. After adding salt, an obvious fluorescence phenomenon is observed. If the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion shows fluorescence reaction without adding salt or no fluorescence reaction is observed after adding salt, the 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion is judged to be a substandard product. S2. Pour the qualified 8-hydroxyquinoline aluminum-nano silver-acrylate hybrid emulsion from S1 into a mixing tank and add solvent, defoamer, leveling agent, neutralizer, abrasion resistant agent and water-based color paste in sequence. After dispersing evenly, filter to obtain water-based ink. S3. Weigh out the water-based ink, put it into a beaker, and observe it under a UV lamp: if there is no fluorescence, the water-based ink does not contain halogens; if there is fluorescence, the water-based ink contains halogens.

9. The rapid detection method for trace halogens in water-based inks as described in claim 8, characterized in that, The salt in S1 is iodine-free edible salt; the ultraviolet lamps in S1 and S3 are ultraviolet generating devices capable of emitting ultraviolet light in the wavelength range of 100-200nm UVD band, 200-275nm UVC band, 275-320nm UVB band, and 320-400nm UVA band.

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