Fluorescent green toner with enhanced brightness

Abstract

The present invention is entitled "Fluorescent Green Toner with Enhanced Brightness." The present invention provides a fluorescent green toner. In embodiments, the fluorescent green toner comprises: resin particles incorporating a fluorescent agent, the resin particles comprising a resin, a fluorescent whitening agent, and a yellow fluorescent agent having an absorption spectrum overlapping a fluorescent emission spectrum of the fluorescent whitening agent; and a cyan colorant; resin particles incorporating a blue dye, the resin particles incorporating a blue dye comprising the resin and a blue dye; or both. The fluorescent green toner has a weight ratio of the yellow fluorescent agent to the cyan colorant and, if present, the blue dye in a range of 100: 1 to 0.2: 1, and the fluorescent green toner exhibits Forster resonance energy transfer (FRET) under UV light irradiation. Methods of making and using the fluorescent green toner are also provided.

Description

Background Technology

[0001] Conventional electrostatic copying systems for toner applications consist of four stations: cyan, magenta, yellow, and black (CMYK) toner stations. These, along with other electrostatic copying systems, can print special colors, including fluorescent toners. Various fluorescent toners have been developed, but improved fluorescent toners are desired. Summary of the Invention

[0002] This disclosure provides a fluorescent green toner. Related methods are also provided.

[0003] In one aspect, a fluorescent green toner is provided. In an embodiment, the fluorescent green toner comprises: resin particles doped with a fluorescent agent, the resin particles comprising a resin, a fluorescent whitening agent, and a yellow fluorescent agent, the yellow fluorescent agent having an absorption spectrum overlapping with the fluorescence emission spectrum of the fluorescent whitening agent; and a cyan colorant; resin particles doped with a blue dye, the resin particles doped with the blue dye comprising the resin and the blue dye; or both. The fluorescent green toner has a weight ratio of yellow fluorescent agent to cyan colorant and, if present, blue dye in the range of 100:1 to 0.2:1, and the fluorescent green toner exhibits Foster resonance energy transfer (FOR) under UV light irradiation. Resonance Energy Transfer) (FRET).

[0004] On the other hand, a method for preparing a fluorescent green toner is provided. In an embodiment, such a method includes forming one or more fluorescent latexes comprising a fluorescent whitening agent, a yellow fluorescent agent having an absorption spectrum overlapping the fluorescence emission spectrum of the fluorescent whitening agent, a first type of amorphous resin, and a second type of amorphous resin; forming a cyan dispersion comprising a cyan colorant and a surfactant; forming a mixture comprising: the one or more fluorescent latexes; the cyan dispersion; one or more emulsions comprising a crystalline resin, the first type of amorphous resin, and the second type of amorphous resin; and optionally, a wax dispersion; agglomerating the mixture to form particles of a predetermined size; forming a shell on the particles of the predetermined size to form core-shell particles; and agglomerating the core-shell particles to form a fluorescent green toner. The fluorescent green toner has a weight ratio of yellow fluorescent agent to cyan colorant and blue dye in the range of 100:1 to 0.2:1, and the fluorescent green toner exhibits FRET under UV light irradiation. Attached Figure Description

[0005] The exemplary embodiments of this disclosure will be described below with reference to the accompanying drawings.

[0006] Figure 1 The reflectance spectrum of the fluorescent green toner according to an exemplary embodiment is shown. The toner mass area (TMA) is 0.5 mg / cm². 2 . Detailed Implementation

[0007] This disclosure provides a fluorescent green toner, a method for preparing the toner, and a method for using the toner.

[0008] The fluorescent green toner comprises resin particles doped with a fluorescent agent and resin particles doped with a cyan colorant and / or a blue dye. The resin particles doped with a fluorescent agent are resin particles doped with a yellow fluorescent agent. Optionally, but preferably, a fluorescent whitening agent is also incorporated. The yellow fluorescent agent and the fluorescent whitening agent (if present) are selected such that they form a pair capable of undergoing Foster resonance energy transfer (FRET). Therefore, this pair may be referred to as an FRET pair. The fluorescent green toner particles may take the form of a core comprising resin particles doped with a fluorescent agent and resin particles doped with a cyan colorant and / or a blue dye, and a shell above the core, the shell further comprising one or more resins, which may be the same as or different from the one or more resins in the core. The resins of the resin particles doped with a fluorescent agent and the resin particles doped with a blue dye may be the same or different.

[0009] Although several fluorescent toners have been developed, incorporating fluorescent agents along with colorants into toners without negatively impacting their optical properties is particularly challenging. For example, the fluorescence of a fluorescent agent is easily quenched within a toner, resulting in the toner exhibiting little or no fluorescence. This disclosure is based, at least in part, on the development of an improved toner preparation method that prevents such quenching and produces a green toner that emits fluorescence under ultraviolet (UV) light (which can be provided by sunlight) and has a high brightness L* value. Furthermore, due to the FRET pair as described above, the overall fluorescence emission from the fluorescent green toner is increased, thereby enhancing the brightness and color intensity of the fluorescent green toner.

[0010] fluorescent agents

[0011] As described above, a fluorescent green toner is provided comprising a fluorescent whitening agent and a yellow fluorescent agent, which are selected such that they form a FRET pair. The fluorescent whitening agent and the yellow fluorescent agent are each characterized by their absorption and emission spectra. For the FRET pair to form, the emission spectrum of the fluorescent whitening agent must sufficiently overlap with the absorption spectrum of the yellow fluorescent agent. When the fluorescent whitening agent is excited by light (e.g., ultraviolet (UV) light), the excited fluorescent whitening agent transfers energy to the yellow fluorescent agent via nonradiative energy transfer to induce fluorescence emission from the yellow fluorescent agent. UV light can be provided by sunlight, which includes UV light. The degree of overlap between the normalized emission spectrum of the fluorescent whitening agent and the normalized absorption spectrum of the yellow fluorescent agent does not need to be complete. Partial overlap still allows FRET between the pair. However, the greater the overlap, the greater the FRET efficiency and the greater the overall fluorescence emission from the fluorescent green toner. In the implementation plan, the degree of overlap is greater than 5%, greater than 15%, greater than 20%, greater than 30%, or in the range of 30% to 100%.

[0012] In the embodiments, the optical brightener has an absorption spectrum spanning the 300 nm to 400 nm range and an emission spectrum spanning the 380 nm to 650 nm range. This includes optical brighteners having an absorption spectrum spanning the 300 nm to 380 nm range. This includes optical brighteners having an emission spectrum spanning the 400 nm to 550 nm range. It is also desirable that the optical brightener does not absorb light in the 380 nm to 700 nm range. The phrase "does not absorb light" encompasses zero absorption, but also includes a small amount of absorption, provided that the optical brightener appears colorless to the human eye. As mentioned above, the yellow fluorescent agent has an absorption spectrum that overlaps with the emission spectrum of the optical brightener. In the embodiments, the yellow fluorescent agent has an absorption spectrum spanning the 370 nm to 520 nm range.

[0013] FRET efficiency is also related to the separation distance (d) between the donor (fluorescent brightener) and acceptor (fluorescent dye) molecules (efficiency ∝ d). -6 Therefore, in order to practically achieve FRET in the fluorescent green toner of the present invention, the fluorescent whitening agent and fluorescent dye molecules are sufficiently close together (i.e., present at a sufficiently high concentration, although not high enough to cause fluorescence quenching) and homogeneously distributed within the resin particles. When the fluorescent agent is combined with other components such as toner particles, the homogeneous distribution and encapsulation of the fluorescent whitening agent and yellow fluorescent agent within the toner particles can also be used to prevent fluorescence quenching. Encapsulation refers to the absence of the relevant component (e.g., fluorescent agent) at or on the surface of the toner particles. The toner preparation method for achieving homogeneous distribution and encapsulation of the fluorescent agent to prevent quenching and promote FRET is described in more detail below. Confirmation of fluorescence emission and FRET can be performed as further described below.

[0014] Examples of fluorescent brighteners include the following: Fluorescent Brightener 184, Optical Brightener 1 (Fluorescent Brightener 393), Optical Brightener 2, Optical Brightener 3, Optical Brightener C, Optical Brightener OB, Optical Brightener R, Optical Brightener Hostalux KSN, Optical Brightener Hostalux KCB, Optical Brightener Telalux KSB, Fluorescent Brightener 127, CBS-127, Optical Brightener PF, Optical Brightener UVT1, Optical Brightener ST, Optical Brightener OEF, Optical Brightener RT, Tinopal CBS-X, DMS / AMS, CBS-155, 378, 367, 368, 185, 199, 199:1, 199:2, Optical Brightener ER-IV, Optical Brightener ER-V, Optical Brightener 4BK, Optical Brightener ER-I / ER-II L, Optical Brightener ER-II / ER-II L, optical brighteners EBF / EBF-L, PF / DT, BA, CXT, R4, MST-L, BAC, SWN / AW-L, WGS, NFW, PC, BBU / BBU-L, VBL / VBL-L. In this embodiment, the fluorescent brightener is fluorescent brightener 184. Combinations of different types of fluorescent brighteners may be used.

[0015] Exemplary yellow fluorescent agents include the following substances: Solvent Yellow 160:1, Solvent Yellow 98, Solvent Yellow 43, and Basic Yellow 40. In embodiments, the fluorescent dye is Solvent Yellow 160:1, Solvent Yellow 98, or a combination thereof.

[0016] Combinations of different types of fluorescent whitening agents and different types of yellow fluorescent agents can be used to make fluorescent green toners contain more than one FRET pair.

[0017] The total amount of fluorescent agents (one or more fluorescent whitening agents and one or more yellow fluorescent agents) may be present in the fluorescent green toner in an amount ranging from, for example, 0.1 wt% to -10 wt%. This includes total amounts of 0.1 wt% to 8 wt%, 0.2 wt% to 6 wt%, 0.5 wt% to 5 wt%, and 1 wt% to 2 wt%. These ranges can be used to achieve appropriate concentrations to ensure FRET while also preventing fluorescence quenching. The relative amounts of fluorescent whitening agents and yellow fluorescent agents in the fluorescent green toner may vary. In embodiments, the weight ratio of fluorescent whitening agent to yellow fluorescent agent is in the range of 1:200 to 1:0.01, 1:50 to 1:0.05, or 1:10 to 1:0.5.

[0018] Cyan colorant / blue dye

[0019] The toner of this invention comprises a cyan colorant, a blue dye, or both. Cyan colorants include Pigment Blue 15:3, Pigment Blue 15:1, Pigment Blue 15:2, Pigment Blue 15:4, and Pigment Blue 15:6. Blue dyes include Solvent Blue 67, Solvent Blue 104, etc. Different types of cyan colorants, blue dyes, or combinations thereof can be used. However, in embodiments, only Pigment Blue 15:3 is used. The cyan colorant is typically encapsulated within the toner particles such that no cyan colorant is present at or on the surface of the particles. Encapsulation can be confirmed using scanning and transmission electron microscopy (SEM / TEM). The cyan colorant is typically homogeneously distributed throughout the resin matrix of the toner particles. This distribution can also be confirmed using SEM / TEM. The blue dye can be homogeneously distributed and encapsulated as described above for fluorescent agents.

[0020] The relative amounts of yellow fluorescent agent and cyan colorant are selected to achieve color channels a* of -50 to -90 and color channels b* of 60 to 100. (The color channels are further described below.) This includes color channels a* of -60 to -80 and color channels b* of 60 to 80. These relative amounts correspond to yellow:cyan / blue weight ratios in the range of 100:1 to 0.2:1. This includes 70:1 to 1:1, 50:1 to 10:1, 10:1 to 1:1, and 5:1 to 1:1.

[0021] resin

[0022] The toner of the present invention may comprise a variety of resins, said resins providing a polymer matrix for accommodating both the aforementioned cyan colorant / blue dye and fluorescent agent. The toner of the present invention may comprise more than one different type of resin. The resin may be an amorphous resin, a crystalline resin, or a mixture of crystalline and amorphous resins. The resin may be a polyester resin, including amorphous polyester resin, crystalline polyester resin, or a mixture of crystalline and amorphous polyester resins.

[0023] Crystalline resin

[0024] The crystalline resin can be a crystalline polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. Suitable organic diols for forming crystalline polyesters include aliphatic diols having about 2 to about 36 carbon atoms, such as 1,2-ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethylpropane-1,3-diol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, combinations thereof, and their structural isomers. The aliphatic diol can be selected, for example, in an amount from about 40 mol% to about 60 mol%, from about 42 mol% to about 55 mol%, or from about 45 mol% to about 53 mol% of the resin, and the second diol can be selected in an amount from about 0 mol% to about 10 mol% of the resin or from about 1 mol% to about 4 mol% of the resin.

[0025] Examples of organic diacids or diesters (including vinyl diacids or vinyl diesters) selected for the preparation of crystalline resins include oxalic acid, succinic acid, glutaric acid, adipic acid, octanoic acid, azelaic acid, sebacic acid, fumaric acid, dimethyl fumarate, dimethyl itaconic acid, cis-1,4-diacetoxy-2-butene, diethyl fumarate, diethyl maleate, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, cyclohexanedicarboxylic acid, malonic acid, and mesonic acid, their diesters or anhydrides. The organic diacid may be selected, for example, in an amount from about 40 mol% to about 60 mol% of the resin, from about 42 mol% to about 52 mol% of the resin, or from about 45 mol% to about 50 mol% of the resin, and the second diacid may be selected in an amount from about 0 mol% to about 10 mol% of the resin.

[0026] Polycondensation catalysts that can be used to form crystalline (and amorphous) polyesters include tetraalkyl titanates, dialkyl tin oxides such as dibutyltin oxide, tetraalkyltin such as dibutyltin dilaurate, and dialkyl tin oxide hydroxides such as butyltin hydroxide, aluminum alkoxides, alkyl zinc, dialkyl zinc, zinc oxide, stannous oxide, or combinations thereof. Based on the starting diacid or diester used to generate the polyester resin, such catalysts can be used, for example, in amounts from about 0.01 mol% to about 5 mol%.

[0027] Examples of crystalline resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutene, polyisobutyrate, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polypropylene, and mixtures thereof. Specific crystalline resins can be polyester-based, such as poly(ethylene adipate), poly(propylene adipate), poly(butylene adipate), poly(pentylene adipate), poly(hexylene adipate), poly(octylene adipate), poly(ethylene succinate), poly(propylene succinate), poly(butylene succinate), poly(pentylene succinate), poly(hexylene succinate), poly(ethylene sebate), poly(propylene sebate), poly(butylene sebate), poly(pentylene sebate), and poly(hexylene sebate). Poly(octyl sebacate), poly(decanoate), poly(decanoate), poly(ethylene decanoate), poly(ethylene dodecanoate), poly(nonanediol sebacate), poly(nonanediol decanoate), copolymer (ethylene fumarate)-copolymer (ethylene sebacate), copolymer (ethylene fumarate)-copolymer (ethylene decanoate), copolymer (ethylene fumarate)-copolymer (ethylene decanoate), copolymer (ethylene fumarate)-copolymer (ethylene dodecanoate), copolymer (2,2-dimethylpropane-1,3-diol-decanoate)-copolymer (nonanediol decanoate), poly(octyl adipate), and mixtures thereof. Examples of polyamides include poly(ethylene glycol-adipamide), poly(propylene glycol-adipamide), poly(butanediol-adipamide), poly(pentanediol-adipamide), poly(hexanediol-adipamide), poly(octanediol-adipamide), poly(ethylene glycol-succinimide), poly(propylene glycol-decanoyldiamide), and mixtures thereof. Examples of polyimides include poly(ethylene glycol-adipamide), poly(propylene glycol-adipamide), poly(butanediol-adipamide), poly(pentanediol-adipamide), poly(hexanediol-adipamide), poly(octanediol-adipamide), poly(ethylene glycol-succinimide), poly(propylene glycol-succinimide), poly(propylene glycol-succinimide), poly(butanediol-succinimide), and mixtures thereof.

[0028] In the implementation scheme, the crystalline polyester resin has the following formula (I).

[0029]

[0030] Each of a and b can be in the range of 1 to 12, 2 to 12, or 4 to 12, and further, p can be in the range of 10 to 100, 20 to 80, or 30 to 60. In an embodiment, the crystalline polyester resin is poly(1,6-hexanediol-1,12-dodecanoate), which can be generated by reacting dodecanoic acid with 1,6-hexanediol.

[0031] As described above, the crystalline polyester resin disclosed in this invention can be prepared by a polycondensation method, by reacting a suitable organic diol with a suitable organic diacid in the presence of a polycondensation catalyst. However, in some cases where the boiling point of the organic diol is from about 180°C to about 230°C, an equimolar ratio of stoichiometric organic diol and organic diacid can be used, and an excess of diol (such as about 0.2 mol equivalents to 1 mol equivalent of ethylene glycol or propylene glycol) can be used and removed by distillation during the polycondensation process. The amount of catalyst used can vary and can be selected, for example, from about 0.01 mol% to about 1 mol% or from about 0.1 mol% to about 0.75 mol% of the crystalline polyester resin.

[0032] The crystalline resin may be present, for example, in an amount of about 1% to about 85% by weight, about 5% to about 50% by weight, or about 10% to about 35% by weight, based on the weight of the toner.

[0033] The crystalline resin can have various melting points, such as about 30°C to about 120°C, about 50°C to about 90°C, or about 60°C to about 80°C. The crystalline resin can have a number-average molecular weight (Mn) of, for example, about 1,000 to about 50,000, about 2,000 to about 25,000, or about 5,000 to about 20,000, as measured by gel permeation chromatography (GPC). n ), and weight-average molecular weights (Mi) as determined by GPC, for example, from about 2,000 to about 100,000, from about 3,000 to about 80,000, or from about 10,000 to about 30,000. w The molecular weight distribution of the crystalline resin (M). w / M n () can be, for example, about 2 to about 6, about 3 to about 5, or about 2 to about 4.

[0034] Amorphous resin

[0035] The resin can be an amorphous polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. Examples of diacids or diesters include vinyl diacids or vinyl diesters used to prepare amorphous polyesters, including dicarboxylic acids or diesters such as terephthalic acid, phthalic acid, isophthalic acid, fumaric acid, trimellitic acid, dimethyl fumarate, dimethyl itaconic acid, cis-1,4-diacetoxy-2-butene, diethyl fumarate, diethyl maleate, maleic acid, succinic acid, itaconic acid, succinic anhydride, dodecyl succinic acid, and dodecyl succinic acid. Succinic anhydride, glutaric acid, glutaric anhydride, adipic acid, pimelic acid, octanoic acid, azelaic acid, dodecanoic acid, dimethyl terephthalate, diethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, dimethyl phthalate, phthalic anhydride, diethyl phthalate, dimethyl succinate, dimethyl fumarate, dimethyl maleate, dimethyl glutarate, dimethyl adipate, dimethyl dodecyl succinate, and combinations thereof. The organic diacid or diester may be present, for example, in amounts from about 40 mol% to about 60 mol% of the resin, from about 42 mol% to about 52 mol% of the resin, or from about 45 mol% to about 50 mol% of the resin.

[0036] Examples of diols that can be used to generate amorphous polyesters include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, pentanediol, hexanediol, 2,2-dimethylpropanediol, 2,2,3-trimethylhexanediol, heptanediol, dodecanediol, bis(hydroxyethyl)-bisphenol A, bis(2-hydroxypropyl)-bisphenol A, 1,4-cyclohexanediethanol, 1,3-cyclohexanediethanol, xylenediethanol, cyclohexanediol, diethylene glycol, bis(2-hydroxyethyl)oxide, dipropylene glycol, dibutene, and combinations thereof. The amount of the selected organic diol can vary; for example, the organic diol may be present in amounts from about 40 mol% to about 60 mol% of the resin, from about 42 mol% to about 55 mol% of the resin, or from about 45 mol% to about 53 mol% of the resin.

[0037] Examples of suitable amorphous resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutene, polyisobutyrates, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polypropylene, and mixtures thereof.

[0038] Unsaturated amorphous polyester resins can be used as resins. Examples of such resins include those disclosed in U.S. Patent No. 6,063,827, the entire disclosure of which is incorporated herein by reference. Exemplary unsaturated amorphous polyester resins include, but are not limited to, poly(propoxylated bisphenol cofuran), poly(ethoxylated bisphenol cofuran), poly(butoxylated bisphenol cofuran), poly(copropoxylated bisphenol coethoxylated bisphenol cofuran), poly(1,2-propanediol fumarate), poly(propoxylated bisphenol comaleate), poly(ethoxylated bisphenol comaleate), poly(butoxylated bisphenol comaleate), poly(copropoxylated bisphenol coethoxylated bisphenol comaleate), poly(1,2-propanediol maleate), poly(propoxylated bisphenol coitaminate), poly(ethoxylated bisphenol coitaminate), poly(butoxylated bisphenol coitaminate), poly(copropoxylated bisphenol coethoxylated bisphenol coitaminate), poly(1,2-propanediol itaconic acid), and combinations thereof.

[0039] Suitable polyester resins can be amorphous polyesters, such as poly(propoxylated bisphenol A cofumarate) resins. Examples of such resins and methods of their preparation include those disclosed in U.S. Patent No. 6,063,827, the entire disclosure of which is incorporated herein by reference.

[0040] Suitable polyester resins include amorphous acidic polyester resins. Amorphous acidic polyester resins can be based on any combination of propoxylated bisphenol A, ethoxylated bisphenol A, terephthalic acid, fumaric acid, and dodecenyl succinic anhydride, such as poly(propoxylated bisphenol-co-terephthalate-fumarate-dodecenyl succinate). Another amorphous acidic polyester resin that can be used is poly(propoxylated-ethoxylated bisphenol-co-terephthalate-dodecenyl succinate-trimethoxyaniline).

[0041] Examples of linear propoxylated bisphenol A fumarate resins that can be used as resins are available under the trade name SPAMII from Resana S / A Industrias Quimicas, Sao Paulo, Brazil. Other propoxylated bisphenol A fumarate resins that can be used and are commercially available include GTUF and FPESL-2 from Kao Corporation, Japan, and EM181635 from Reichhold, Research Triangle Park, NC.

[0042] The amorphous resin or combination of amorphous resins may be present, for example, in amounts of about 5% to about 95% by weight, about 30% to about 90% by weight, or about 35% to about 85% by weight, based on the weight of the toner.

[0043] Amorphous resins or combinations of amorphous resins may have glass transition temperatures of about 30°C to about 80°C, about 35°C to about 70°C, or about 40°C to about 65°C. The glass transition temperature can be measured using differential scanning calorimetry (DSC). Amorphous resins may have M values ​​such as about 1,000 to about 50,000, about 2,000 to about 25,000, or about 1,000 to about 10,000, as measured by GPC. n And M as determined by GPC, for example, about 2,000 to about 100,000, about 5,000 to about 90,000, about 10,000 to about 90,000, about 10,000 to about 30,000, or about 70,000 to about 100,000. w .

[0044] One, two, or more resins can be used in the toners of the present invention. When using two or more resins, the resins can have any suitable ratio (e.g., by weight) such as about 1% (first resin) / 99% (second resin) to about 99% (first resin) / 1% (second resin), about 10% (first resin) / 90% (second resin) to about 90% (first resin) / 10% (second resin). When the resin comprises a combination of amorphous and crystalline resins, the resins can have a weight ratio such as about 1% (crystalline resin) / 99% (amorphous resin) to about 99% (crystalline resin) / 1% (amorphous resin) or about 10% (crystalline resin) / 90% (amorphous resin) to about 90% (crystalline resin) / 10% (amorphous resin). In some embodiments, the weight ratio of the resins is about 80% to about 60% amorphous resin and about 20% to about 40% crystalline resin. In such embodiments, the amorphous resin can be a combination of amorphous resins, such as a combination of two amorphous resins.

[0045] The resin in the toner of this invention may have acid groups that can be present at the resin terminals. Possible acid groups include carboxylic acid groups, etc. The number of carboxylic acid groups can be controlled by adjusting the materials used to form the resin and the reaction conditions. In an embodiment, the resin is a polyester resin having an acid value of about 2 mg KOH / g resin to about 200 mg KOH / g resin, about 5 mg KOH / g resin to about 50 mg KOH / g resin, or about 5 mg KOH / g resin to about 15 mg KOH / g resin. The acid-containing resin can be dissolved in a tetrahydrofuran solution. The acid value can be detected by titration with a KOH / methanol solution containing phenolphthalein as an indicator. The acid value can then be calculated based on the equivalent number of KOH / methanol required to neutralize all acid groups on the resin at the titration endpoint.

[0046] wax

[0047] Optionally, wax may be included in the toner of the present invention. A single type of wax or a mixture of two or more different waxes may be used. For example, a single wax may be added to improve specific toner properties, such as toner particle shape, the presence and amount of wax on the surface of the toner particles, charging characteristics and / or fusion characteristics, gloss, peeling, staining properties, etc. Alternatively, a combination of waxes may be added to provide a variety of properties to the toner composition.

[0048] When included, wax may be present, for example, in amounts of about 1% to about 25% by weight of the toner, or about 5% to about 20% by weight of the toner particles.

[0049] When using waxes, the waxes may include any of the various waxes conventionally used in emulsion aggregate toners. Selectable waxes include those having an average molecular weight, for example, from about 500 to about 20,000, or from about 1,000 to about 10,000. Waxes that can be used include, for example, polyolefins, such as polyethylene (including linear polyethylene waxes and branched polyethylene waxes), polypropylene (including linear polypropylene waxes and branched polypropylene waxes), polymethylene waxes, polyvinyl chloride / amide, polytetrafluoroethylene, polytetrafluoroethylene / amide, and polybutene waxes, such as those commercially available from Allied Chemical and Petrolite Corporation, such as POLYWAX commercially available from Baker Petrolite. TM Polyethylene wax, wax emulsion purchased from Michaelman, Inc. and Daniels Products Company, and EPOLENE N-15 available commercially from Eastman Chemical Products, Inc. TM And a VISCOL 550-P purchased from Sanyo Kasei KK TM(Low weight average molecular weight polypropylene); plant-based waxes, such as carnauba wax, rice wax, candelilla wax, sumac wax, and jojoba oil; animal-based waxes, such as beeswax; mineral-based and petroleum-based waxes, such as montan wax, ceresin wax, pure ceresin wax, paraffin wax, microcrystalline wax (such as waxes derived from crude oil distillation), silicone wax, mercapto wax, polyester wax, urethane wax; modified polyolefin waxes (such as carboxylic acid-terminated polyethylene wax or carboxylic acid-terminated polypropylene wax); Fischer-Tropsch waxes; ester waxes obtained from higher fatty acids and higher alcohols, such as octadecyl stearate and eicosyl stearate. Dialkyl dialkyl esters; ester waxes obtained from higher fatty acids and monovalent or polyvalent lower alcohols, such as butyl stearate, propyl oleate, glyceryl monostearate, glyceryl distearate, and pentaerythritol tetrabenzyl ester; ester waxes obtained from higher fatty acids and polyvalent alcohol polymers, such as diethylene glycol monostearate, dipropylene glycol distearate, diglyceryl distearate, and triglyceryl tetrastearate; sorbitol higher fatty acid ester waxes such as sorbitol monostearate; and cholesterol higher fatty acid ester waxes such as cholesterol stearate. Examples of functionalized waxes that can be used include, for example, amines and amides (e.g., AQUA SUPERSLIP 6550 purchased from Micro Powder Inc.). TM SUPERSLIP 6530 TM ), fluorinated waxes (such as POLYFLUO 190 purchased from Micro Powder Inc.) TM POLYFLUO 200 TM POLYSILK 19 TM POLYSILK14 TM ), mixed fluorinated amide waxes (such as aliphatic polar amide functionalized waxes); aliphatic waxes composed of esters of hydroxylated unsaturated fatty acids (e.g., MICROSPERSION 19). TM Also purchased from Micro Powder Inc.), imide, ester, quaternary ammonium, carboxylic acid, or acrylic polymer emulsions (e.g., JONCRYL 74). TM 89 TM 130 TM 537 TM and 538 TM The ingredients include chlorinated polypropylene and polyethylene (purchased from SC Johnson Wax), chlorinated polypropylene and polyethylene (purchased from Allied Chemical and Petrolite Corporation), and SC Johnson wax. Mixtures and combinations of the aforementioned waxes may also be used in the embodiments. The wax may be included as, for example, a fuser roller stripper. In the embodiments, the wax may be crystalline or amorphous.

[0050] Toner preparation method

[0051] To form the fluorescent green toner of the present invention, any of the above-mentioned resins can be provided as one or more emulsions, for example, by using a solvent-based phase inversion emulsification method. The emulsion can then be used as a raw material to form the toner, for example, by using an emulsion aggregation and coalescence (EA) method.

[0052] To achieve the encapsulation and homogeneous distribution of cyan colorant, a separate dispersion containing cyan colorant and surfactant is typically used in the colorant preparation process. Illustrative surfactants include anionic surfactants such as diphenyl ether disulfonate, ammonium dodecyl sulfate, sodium dodecylbenzene sulfonate, dodecylbenzene sulfonic acid, sodium alkylnaphthalene sulfonate, sodium dialkyl sulfosuccinate, sodium alkyl diphenyl ether disulfonate, potassium salts of alkyl phosphates, sodium polyoxyethylene lauryl ether sulfate, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl ether sulfate, triethanolamine polyoxyethylene alkyl ether sulfate, sodium naphthalene sulfate and sodium naphthalene sulfonate formaldehyde condensate, and mixtures thereof; and nonionic surfactants such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene oil-based ether, polyoxyethylene dehydrated sorbitol monolaurate, polyoxyethylene stearyl ether, dialkylphenoxy poly(ethyleneoxy)ethanol, and mixtures thereof. However, in this embodiment, the surfactant is dodecylbenzenesulfonic acid, and this surfactant is present in the separate dispersion in an amount ranging from 1.5% to 4% by weight compared to the amount of cyan colorant. This surfactant and these amounts are used to achieve the encapsulation and homogeneous distribution of the cyan colorant in the toner particles. Once the cyan colorant is incorporated into the toner particles using this surfactant and these amounts, it can be referred to as a "resin incorporating cyan colorant." As mentioned above, the encapsulation and homogeneous distribution can be confirmed using SEM / TEM.

[0053] As described above, to achieve similar encapsulation and homogeneous distribution of the fluorescent agent, and to prevent fluorescence quenching and promote FRET, a separate latex (fluorescent latex) containing the desired fluorescent agent and the desired resin is typically used in the preparation process. The desired fluorescent agent may include both fluorescent whitening agents and yellow fluorescent agents. The desired resin may include more than one type of resin. It is desired that the FRET pair forms in the same fluorescent latex to promote FRET. However, also as described above, separate fluorescent latexes can be prepared and used to form the fluorescent green toner of the present invention, for example, one fluorescent latex containing a fluorescent whitening agent and another fluorescent latex containing a yellow fluorescent agent.

[0054] As described above, each fluorescent latex may contain a single type of resin, such as a single type of amorphous polyester resin, or multiple types of resin, such as two different types of amorphous polyester resin. In such embodiments, one of these amorphous polyester resins has a larger M than the other. n Or M w In embodiments where two different types of amorphous polyester resins are used, the weight ratio of the two types can be from 2:3 to 3:2. This includes a 1:1 weight ratio. Alternatively, two separate fluorescent latexes can be used, each containing a different type of amorphous polyester resin. However, one or more fluorescent latexes together provide two different types of amorphous polyester resins within this weight ratio range. Once incorporated into the resin particles, these weight ratios can be used to ensure a homogeneous distribution of the fluorescent agent. This also prevents fluorescence quenching while promoting FRET.

[0055] Once the fluorescent agent / resin is incorporated into the toner particles using the methods and fluorescent dosages described above, the fluorescent agent / resin can be referred to as "fluorescent agent-incorporated resin".

[0056] If a blue dye is used, it can be incorporated into the colorant as a separate latex, as described above for fluorescent latex.

[0057] If a resin is incorporated into toner particles using an emulsion that does not contain fluorescent agents / colorants / dyes, the resin can be referred to as a resin without fluorescent agents / colorants / dyes, or simply as "resin," without the phrase "with fluorescent agents / colorants / dyes."

[0058] If wax is used, it can be incorporated into the colorant as a separate dispersion of wax in water.

[0059] In embodiments, the fluorescent green toner of the present invention is prepared by an EA method, such as by a method comprising the following steps: agglomerating a mixture of the following substances: an emulsion containing a resin, a cyan colorant or a blue dye or both; a fluorescent whitening agent; a yellow fluorescent agent; and optionally, a wax; and subsequently agglomerating the mixture. As described above, the cyan colorant is typically provided to the mixture as a separate dispersion, and the blue dye is typically provided to the mixture as a separate latex. Similarly, the fluorescent whitening agent / yellow fluorescent agent is typically provided to the mixture as one or more separate fluorescent latexes as described above (but preferably one to ensure FRET). The resin-containing emulsion may contain one or more resins, or different resins may be provided as different emulsions. The resin-containing one or more emulsions typically do not contain fluorescent agents / colorants / dyes, and are therefore free of fluorescent agents / colorants / dyes.

[0060] Next, the mixture can be homogenized, which can be achieved by mixing at a speed of about 600 rpm to about 6,000 rpm. Homogenization can be achieved by any suitable device, including, for example, an IKA ULTRA TURRAXT50 probe homogenizer. An agglomerant can be added to the mixture. Any suitable agglomerant can be used. Suitable agglomerants include, for example, aqueous solutions of divalent or polyvalent cationic materials. The agglomerant can be, for example, an inorganic cationic agglomerant, such as polyaluminum halide, such as polyaluminum chloride (PAC), or the corresponding bromide, fluoride, or iodide; polyaluminum silicate, such as polysulfoaluminum silicate (PASS); or water-soluble metal salts, including aluminum chloride, aluminum nitrite, aluminum sulfate, potassium aluminum sulfate, calcium acetate, calcium chloride, calcium nitrite, calcium oxide, calcium sulfate, magnesium acetate, magnesium nitrate, magnesium sulfate, zinc acetate, zinc nitrate, zinc sulfate, zinc chloride, zinc bromide, magnesium bromide, copper chloride, and copper sulfate; or combinations thereof. It can be done below the glass transition temperature (T) of the resin. g The agglomerant is added to the mixture at a temperature of 100°C. The agglomerant can also be added to the mixture under homogenization conditions.

[0061] The agglomerant may be added to the mixture in amounts such as: from about 0% to about 10% by weight of the total resin, from about 0.2% to about 8% by weight of the total resin, or from about 0.5% to about 5% by weight of the total resin.

[0062] The mixture can be agglomerated until a predetermined desired particle size is achieved. The predetermined desired particle size refers to the expected particle size determined prior to formation, and the particle size is monitored during the growth process until that size is reached. Sampling can be performed during the growth process, and the volume average particle size can be analyzed, for example, using a Coulter counter. Therefore, agglomeration can be carried out by maintaining an elevated temperature, or by slowly raising the temperature to, for example, about 30°C to about 100°C in one embodiment, about 30°C to about 80°C in another embodiment, or about 30°C to about 50°C in another embodiment. While stirring, the temperature can be maintained for a period of about 0.5 hours to about 6 hours, or about 1 hour to about 5 hours in another embodiment, to provide agglomerated particles. Once the predetermined desired particle size is reached, a shell can be added. Before applying the shell, the volume average particle size can be, for example, about 3 μm to about 10 μm, about 4 μm to about 9 μm in another embodiment, or about 6 μm to about 8 μm.

[0063] Shell resin

[0064] After aggregation, but before coalescence, a resin coating can be applied to the aggregated particles to form a shell thereon. Any of the resins described above can be used in the shell. In one embodiment, an amorphous polyester resin is used in the shell. In another embodiment, two amorphous polyester resins are used in the shell. In yet another embodiment, a crystalline polyester resin and two different types of amorphous polyester resins are used in the core, and the same two types of amorphous polyester resins are used in the shell. The shell resin typically does not contain fluorescent agents and is therefore free of fluorescent agents.

[0065] A shell can be applied to aggregated particles by using a shell resin in the form of an emulsion as described above. Such an emulsion can be mixed with the aggregated particles under conditions sufficient to form a coating. For example, shell formation on the aggregated particles can occur at temperatures ranging from approximately 30°C to approximately 80°C, or from approximately 35°C to approximately 70°C. Shell formation can occur over a period of approximately 5 minutes to approximately 10 hours, or from approximately 10 minutes to approximately 5 hours.

[0066] Once the desired toner particle size is achieved, a pH control agent (e.g., an alkali) can be used to adjust the pH of the mixture to a value of about 3 to about 10, or in the embodiments, about 5 to about 9. pH adjustment can be used to freeze (i.e., stop) toner growth. The alkali used to stop toner growth can include any suitable alkali, such as, for example, alkali metal hydroxides, such as, for example, sodium hydroxide, potassium hydroxide, ammonium hydroxide, combinations thereof, etc. In the embodiments, a chelating agent such as ethylenediaminetetraacetic acid (EDTA) can be added to help adjust the pH to the desired value described above. Other chelating agents can be used.

[0067] In the implementation scheme, the size of the core-shell toner particles (before aggregation) can be about 3 μm to about 10 μm, about 4 μm to about 10 μm, or about 6 μm to about 9 μm.

[0068] coalescing

[0069] After agglomerating to the desired particle size and applying a shell, the particles can be aggregated into the desired final shape. This agglomeration is achieved, for example, by heating the mixture to a temperature of about 45°C to about 150°C, about 55°C to about 99°C, or about 60°C to about 90°C, which can be equal to or higher than the glass transition temperature of the resin used to form the toner particles. Heating can continue or the pH of the mixture can be adjusted (e.g., decreased) for a period of time to achieve the desired sphericity. This period of time can be about 1 hour to about 5 hours, or about 2 hours to about 4 hours. Various buffer solutions can be used during agglomeration. The total agglomeration time can be about 1 to about 9 hours, about 1 to about 8 hours, or about 1 to about 5 hours. Stirring can be used during agglomeration, for example, about 20 rpm to about 1000 rpm or about 30 rpm to about 800 rpm.

[0070] After aggregation and / or coalescence, the mixture can be cooled to room temperature. Cooling can be rapid or slow, depending on the requirements. A suitable cooling process may include introducing cold water into a jacket around the reactor. After cooling, the toner particles can be screened, filtered, washed with water, and then dried. Drying can be achieved by any suitable drying method, including, for example, freeze-drying.

[0071] Other additives

[0072] In embodiments, the fluorescent green toner of the present invention may also contain other optional additives. For example, the toner may contain a positive charge control agent or a negative charge control agent. Surface additives may also be used. Examples of surface additives include metal oxides, such as titanium oxide, silicon oxide, aluminum oxide, cerium oxide, tin oxide, mixtures thereof, etc.; colloidal silica and amorphous silica, such as… Metal salts and metal salts of fatty acids (such as zinc stearate, calcium stearate, and magnesium stearate), mixtures thereof; long-chain alcohols, such as UNILIN 700; and mixtures thereof. Each of these surface additives may be present in an amount of about 0.1% to about 5% by weight or about 0.25% to about 3% by weight of the colorant.

[0073] Properties of toners

[0074] The fluorescence of fluorescent green toners and the presence of FRETs present in fluorescent green toners can be confirmed and quantified using a densitometer (such as Hunter, X-Rite, etc.) or a fluorescence spectrometer operated according to the manufacturer's instructions. These systems can be used to determine the luminance L*, color channels a* and b*, and reflectance of fluorescent green toners. Regarding luminance L*, the CIELAB color space (also known as CIE L*a*b*, or sometimes simply "Lab" color space) is a color space defined by the International Commission on Illumination (CIE). It represents colors as three values: luminance L* from black (0) to white (100), a* from green (-) to red (+), and b* from blue (-) to yellow (+).

[0075] Because three parameters are measured, the space itself is a three-dimensional real number space, which allows for an infinite number of possible colors. In implementation, this space is typically mapped to a three-dimensional integer space for numerical representation; therefore, the L*, a*, and b* values ​​are usually absolute and have predefined ranges. The brightness value L* represents the darkest black when L* = 0 and the brightest white when L* = 100. The color channels a* and b* represent true neutral gray values ​​when a* = 0 and b* = 0. The a* axis represents the green-red component, with green in the negative direction and red in the positive direction. The b* axis represents the blue-yellow component, with blue in the negative direction and yellow in the positive direction. The scaling and limitations of the a* and b* axes will depend on the specific implementation but are typically within the range of ±100 or -128 to +127 (signed 8-bit integers).

[0076] As described above, the fluorescent green toner of the present invention is characterized by color channels a* and b* within the aforementioned range. They are also characterized by a luminance L* of at least 75, at least 80, at least 85, or at least 90. Furthermore, compared to a comparative fluorescent green latex having the same composition but without a fluorescent whitening agent, the fluorescent green toner having at least one FRET pair of fluorescent whitening agent and yellow fluorescent agent and exhibiting FRET (due to appropriate concentration and homogeneous distribution) is characterized by having a significantly higher reflectance value. This is demonstrated in the examples below.

[0077] Developer and carrier

[0078] The fluorescent green toner of the present invention can be formulated into a developer composition. The developer composition can be prepared by mixing the toner of the present disclosure with known carrier particles, including coated carriers such as steel, ferrite, etc. Such carriers include those disclosed in U.S. Patent Nos. 4,937,166 and 4,935,326, the entire disclosure of each of which is incorporated herein by reference. The toner may be present in the carrier in amounts of about 1% to about 15% by weight, about 2% to about 8% by weight, or about 4% to about 6% by weight. The carrier particles may also include a core having a polymer coating (such as polymethyl methacrylate (PMMA)) thereon, wherein a conductive component such as conductive carbon black is dispersed. The carrier coating includes silicone resins such as methylsilsesquioxane, fluoropolymers such as polyvinylidene fluoride, mixtures of resins not adjacent in the triboelectric sequence such as polyvinylidene fluoride and acrylic resins, thermosetting resins such as acrylic resins, mixtures thereof, and other known components.

[0079] application

[0080] The fluorescent green toner of this invention can be used in various electrostatic copying methods and various electrostatic copiers. Electrostatic copying imaging methods include, for example, preparing an image using an electrostatic copier, which includes a charging unit, an imaging unit, a photoconductive unit, a developing unit, a transfer unit, and a fixing unit. In embodiments, the developing unit may include a developer prepared by mixing a carrier with any of the toners described herein. The electrostatic copier printer may be a high-speed printer, a black-and-white high-speed printer, a color printer, etc. Once an image is formed with the toner / developer, the image can be transferred to an image receiving medium, such as paper. A fixing roller assembly can be used to fix the toner onto the image receiving medium using heat and pressure.

[0081] Example

[0082] The following examples are provided to illustrate various embodiments of this disclosure. These examples are intended to be illustrative only and are not intended to limit the scope of this disclosure. Furthermore, unless otherwise specified, parts and percentages are by weight. As used throughout this patent specification, "room temperature" means a temperature of 20°C to 25°C.

[0083] Fluorescent latex was prepared as follows. In a 2L reactor at 40°C, 120g of amorphous polyester resin of type I, 80g of amorphous polyester resin of type II, a mixture of fluorescent whitening agent and yellow fluorescent agent were dissolved in a mixture of acetone, ethyl acetate, and ammonia solution (ratio 145g / 48g / 40g). Additional alkaline solution was added to each mixture to completely neutralize the polyester resin. After approximately one hour and complete homogenization, deionized water was added to each mixture. The organic solvent was removed by applying vacuum, and water was added during this process to maintain the desired water content (to achieve the desired solids percentage). Finally, the resulting emulsion was filtered through a 25μm sieve. The emulsion had a particle size of 50-500nm and a solids content of approximately 35%. A fluorescent latex with a total fluorescent agent content of approximately 2% to approximately 7% by weight relative to the total weight of the fluorescent latex was prepared. Approximately 2% by weight of a surfactant (Calfax) was added to stabilize the fluorescent latex.

[0084] As described above, a fluorescent latex is formed, but without the use of fluorescent whitening agents.

[0085] A cyan dispersion comprising deionized water, 15 wt% Pigment Blue 15:3, and a surfactant (sodium dodecylbenzenesulfonate, 2 wt% compared to PB15:3) was prepared. The cyan dispersion had a particle size of 50-500 nm and a solid content of approximately 17%.

[0086] To form the fluorescent green toner, the mixture is formed by combining the following substances: a fluorescent latex; the cyan dispersion; a first emulsion containing a crystalline polyester resin; a second emulsion containing an amorphous polyester resin of a first type; and a third emulsion containing an amorphous polyester resin of a second type. Various relative amounts of fluorescent latex and cyan dispersion are used as shown in Table 1. Aluminum sulfate (ALS) solution is added slowly while each mixture is homogenized. Each highly viscous mixture is transferred to a 2L reactor, and aggregation is initiated by increasing the temperature to approximately 40°C to 48°C. When the particle size (D50v) reaches approximately 7.5 μm, an emulsion containing both amorphous polyester resins is added to the mixture to form a shell on the particles, allowing the particles to continue growing. The particles are frozen by adding a chelating agent and an alkali. The reactor temperature is raised to approximately 84°C to allow aggregation. Heating is stopped when the particles reach the desired sphericity. The particle slurry is quenched, the particle dispersion is collected, and then stirred overnight. The particles are then sieved, washed, and dried.

[0087] Color analysis and reflectance spectra of the fluorescent green toner printed on paper were performed using a Gretag X-rite instrument, following the manufacturer's instructions. The results of the color analysis are shown in Table 1. Figure 1 The reflectance spectra are shown. Table 1 shows the a* and b* values ​​of each sample that fall within the green color space. Figure 1 The results confirmed the emission of green fluorescence from the toner. It also showed that the fluorescent green toners containing fluorescent brighteners (samples 1-4) had a significantly increased peak reflectance (i.e., reflectance values ​​at the peak) compared to the corresponding comparative fluorescent green toners without fluorescent brighteners (samples 5-8, respectively). The increased peak reflectance is believed to be due to FRET occurring between the fluorescent brightener and the yellow fluorescent agent. The results indicate that sample 1 provides a fluorescent green toner with enhanced brightness.

[0088] Table 1. Fluorescent green toners .

[0089]

[0090] It should be understood that the features disclosed above, as well as variations or alternatives to other features and functions, can be combined into many other different systems or applications. Those skilled in the art can then make various substitutions, modifications, changes, or improvements that are not currently foreseen or anticipated, and these are also intended to be covered by the appended claims.

Claims

1. A fluorescent green toner, said fluorescent green toner comprising: Resin particles doped with a fluorescent agent, the resin particles comprising resin, a fluorescent whitening agent, and a yellow fluorescent agent, the yellow fluorescent agent having an absorption spectrum that overlaps with the fluorescence emission spectrum of the fluorescent whitening agent; and The cyan colorant and / or resin particles incorporating blue dye, wherein the resin particles incorporating blue dye comprise the resin and the blue dye. The fluorescent green toner has a weight ratio of the yellow fluorescent agent to the cyan colorant or the blue dye, or the cyan colorant and the blue dye, in the range of 100:1 to 0.2:

1. Furthermore, the fluorescent green toner described therein exhibits Foster resonance energy transfer (FRET) under UV light irradiation.

2. The fluorescent green toner according to claim 1, further comprising a core and a shell above the core, the core comprising: the resin particles doped with the fluorescent agent; the cyan colorant and / or the resin particles doped with the blue dye; a crystalline polyester resin; and optionally, a wax.

3. The fluorescent green toner according to claim 1, wherein the fluorescent green toner comprises the cyan colorant.

4. The fluorescent green toner according to claim 1, wherein the weight ratio is 10:1 to 1:

1.

5. The fluorescent green toner according to claim 1, wherein the fluorescence emission spectrum of the fluorescent whitening agent and the absorption spectrum of the yellow fluorescent agent have an overlap of 30% to 100%.

6. The fluorescent green toner according to claim 1, wherein the fluorescent whitening agent is fluorescent whitening agent 184.

7. The fluorescent green toner according to claim 1, wherein the yellow fluorescent agent is selected from Solvent Yellow 160:1, Solvent Yellow 98, Solvent Yellow 43, Basic Yellow 40, and combinations thereof.

8. The fluorescent green toner according to claim 1, wherein the fluorescent green toner comprises the cyan colorant, wherein the cyan colorant is Pigment Blue 15:

3.

9. The fluorescent green toner according to claim 1, wherein the resin is a combination of two different types of resin.

10. The fluorescent green toner according to claim 9, wherein the two different types of resins are present in the fluorescently incorporated resin particles in a weight ratio of 2:3 to 3:

2.

11. The fluorescent green toner according to claim 10, wherein the two different types of resins are two amorphous polyester resins.

12. The fluorescent green toner according to claim 11, wherein the two amorphous polyester resins are poly(propoxylated bisphenol-co-terephthalic acid-fumaric acid-dodecenyl succinate) and poly(propoxylated-ethoxylated bisphenol-co-terephthalic acid-dodecenyl succinate-trimethicone).

13. The fluorescent green toner according to claim 1, wherein, by weight, the fluorescent green toner has a total amount of the fluorescent whitening agent and the yellow fluorescent agent ranging from 0.5% to 5% by weight, and a weight ratio of the fluorescent whitening agent to the yellow fluorescent agent ranging from 1:10 to 1:0.

5.

14. The fluorescent green toner according to claim 2, wherein the crystalline polyester resin has formula I Formula I Each of a and b is in the range of 1 to 12, and p is in the range of 10 to 100.

15. The fluorescent green toner according to claim 14, wherein the crystalline polyester resin is poly(1,6-hexanediol-1,12-dodecanoate).

16. The fluorescent green toner of claim 1, wherein the fluorescent whitening agent is fluorescent whitening agent 184; the yellow fluorescent agent is solvent yellow 160:1, solvent yellow 98, or a combination thereof; and the cyan colorant is pigment blue 15:

3.

17. The fluorescent green toner of claim 16, further comprising a core and a shell above the core, the core comprising: the fluorescently incorporated resin particles, the cyan colorant; a crystalline polyester resin; and optionally, a wax.

18. The fluorescent green toner according to claim 17, wherein the resin is a combination of poly(propoxylated bisphenol-co-terephthalic acid-fumaric acid-dodecenyl succinate) and poly(propoxylated-ethoxylated bisphenol-co-terephthalic acid-dodecenyl succinate-trimethicone), and the crystalline polyester resin is poly(1,6-hexanediol-1,12-dodecanoate).

19. A method for preparing a fluorescent green toner, the method comprising: One or more fluorescent latexes are formed, the one or more fluorescent latexes comprising a fluorescent whitening agent, a yellow fluorescent agent having an absorption spectrum that overlaps with the fluorescence emission spectrum of the fluorescent whitening agent, a first type of amorphous resin and a second type of amorphous resin; A cyan dispersion is formed, the cyan dispersion comprising a cyan colorant and a surfactant; A mixture is formed comprising: the one or more fluorescent latexes; the cyan dispersion; one or more emulsions comprising a crystalline resin, an amorphous resin of the first type, an amorphous resin of the second type; and optionally, a wax dispersion. The mixture is aggregated to form particles of a predetermined size; A shell is formed on the particles of the predetermined size to form core-shell particles; and The core-shell particles are aggregated to form a fluorescent green toner. The fluorescent green toner has a weight ratio of the yellow fluorescent agent to the cyan colorant in the range of 100:1 to 0.2:

1. Furthermore, the fluorescent green toner described therein exhibits FRET under UV light irradiation.

20. A method of using the fluorescent green toner according to claim 1, the method comprising: An image containing the fluorescent green toner is formed using an electrostatic copier printer; The image containing the fluorescent green toner is transferred to an image receiving medium; as well as The fluorescent green toner is fixed onto the image receiving medium.

Images