Toner Compositions and Additives

Abstract

To provide an additive which can improve frictional electrification with respect to an environmental condition including humidity.SOLUTION: A toner composition contains toner particles having at least one resin, an arbitrarily selective coloring agent, an arbitrarily selective wax, and crosslinked polymer particles on at least a partial outer surface of the toner particles. The crosslinked polymer particles on the surface of the toner particles contain at least one hydrophobic monomer containing a non-fluorinated monomer or a fluorinated monomer having a carbon-to-oxygen (C / O) ratio of 3 or more. The crosslinked polymer particles contain approximately 8 wt.% to approximately 40 wt.% of a second monomer containing two or more vinyl groups, a metal oxide, and an arbitrarily selective charge control agent monomer, in a copolymer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE This disclosure relates generally to toner compositions, and more specifically to toner compositions that include polymeric additives. [Background technology]

[0002] Electrophotographic printing utilizes toner particles that can be produced by a variety of processes. One such process includes an emulsion aggregation ("EA") process in which surfactants are used to form a latex emulsion to form toner particles. See, for example, U.S. Pat. No. 6,120,967, the disclosure of which is incorporated herein by reference in its entirety, for an example of such a process.

[0003] A combination of amorphous and crystalline polyesters can be used in the EA process. This resin combination can provide high gloss and relatively low melting point properties (sometimes called low melt, ultra-low melt, or ULM), which allows for more energy efficiency and faster printing. The use of additives with EA toner particles can be important to achieve optimal toner performance, especially in the charging area.

[0004] Potential problems with toners include sensitivity to environmental conditions, including humidity. For example, in the summer, users complain about background in images when it is hot and humid. In the winter, users complain about bright images when it is cold and dry. Excessive background can also occur due to a loss of charge as the developer ages.

[0005] External toner additives, such as metal oxide particles, are often combined with toner particles to improve selected properties of the toner particles, including flowability, mobility, fixability, and cleaning properties. Various external additives can be used in a single toner composition to enhance different properties of the toner. For example, some additives can be selected to improve charging ability, i.e., triboelectric charging. Others can be selected to improve cleaning performance or humidity resistance. Of course, toner additives optimized for one function should preferably not be detrimental to the functions provided by the various additives.

[0006] There is a continuing need to improve the additives used in forming EA ULM toners. There is also a need to improve the sensitivity of toner compositions to environmental conditions, including relative humidity. Summary of the Invention

[0007] According to various embodiments, a toner composition is provided. The toner composition includes toner particles having at least one resin, an optional colorant, an optional wax, and polymer particles on at least a portion of the outer surface of the toner particles. The crosslinked polymer particles on the surface of the toner particles include at least one hydrophobic monomer, including a non-fluorinated monomer or a fluorinated monomer, or a combination thereof, having a carbon-to-oxygen (C / O) ratio of 3 or greater. The crosslinked polymer particles include two or more vinyl groups present in the copolymer in an amount of about 8% to about 40% by weight. a second monomer comprising , a metal oxide, and optionally a charge control agent monomer 。

[0008] According to various embodiments, a developer is provided. The developer includes a toner composition and a toner carrier. The toner composition includes toner particles having at least one resin, an optional colorant, an optional wax, and crosslinked polymer particles on at least a portion of the outer surface of the toner particles. The crosslinked polymer particles on the surface of the toner particles include at least one hydrophobic monomer, including a non-fluorinated monomer or a fluorinated monomer, or a combination thereof, having a carbon-to-oxygen (C / O) ratio of 3 or greater. The crosslinked polymer particles include two or more vinyl groups present in the copolymer in an amount of about 8% to about 40% by weight. a second monomer comprising , a metal oxide, and optionally a charge control agent monomer 。

[0009] Disclosed herein is a toner additive comprising a polymer resin. The toner additive comprises crosslinked polymer particles and at least one hydrophobic monomer, including a non-fluorinated or fluorinated monomer, or a combination thereof, having a carbon-to-oxygen (C / O) ratio of 3 or greater. The crosslinked polymer particles comprise two or more vinyl groups present in the copolymer in an amount of about 8% to about 40% by weight. a second monomer comprising , a metal oxide, and optionally a charge control agent monomer. [Brief explanation of the drawings]

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the present teachings and, together with the description, serve to explain the principles of the present teachings.

[0011] [Figure 1] 1 shows scanning electron microscope (SEM) images of dried samples according to various embodiments of the present disclosure.

[0012] It should be noted that some details of these figures have been simplified and strict structural accuracy, detail, and scale are not maintained, but rather are drawn to facilitate understanding of the embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present disclosure provides a polymeric additive for use with toner particles. The polymeric toner additive particles include crosslinked polymer particles containing a metal oxide and, optionally, a charge control agent.

[0014] The resulting polymer toner additive particles may be used as additives in toner compositions to enhance the sensitivity to relative humidity and charge stability of the resulting toner. The polymer toner additive particles of the present disclosure can also provide toner particles with a wide range of properties, such as hydrophobicity and charge control, depending on the monomer used to form the polymer. The polymer toner additive particles also provide good toner powder flow and toner heat insulation stability, maintaining good toner flow and charge after exposure to high temperatures and humidity, such as occurs during storage or during printer operation when printing high print runs under high temperature and humidity conditions. The polymer toner additive particles also provide stable toner development from the developer to the photoreceptor, and transfer from the photoreceptor to the imaging substrate, or in imaging systems with an intermediate transfer medium, from the photoreceptor to the intermediate transfer medium and from the intermediate transfer medium to the imaging substrate.

[0015] As discussed above, the polymer additive may be a polymer particle. In some embodiments, the latex copolymer utilized as the additive may include a non-fluorinated hydrophobic monomer, such as an acrylate or methacrylate, having a high C / O ratio. The C / O ratio of such a monomer may be 3 or greater, in some embodiments 4 or greater, and in some embodiments 5 or greater. In some embodiments, the hydrophobic monomer may be a fluorinated monomer.

[0016] In some embodiments, the non-fluorinated hydrophobic monomer having a high C / O ratio may be an aliphatic cycloacrylate. Suitable aliphatic cycloacrylates that can be utilized to form the polymer additive include, for example, cyclohexyl methacrylate, cyclopropyl acrylate, cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cyclopropyl methacrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, isobornyl methacrylate, isobornyl acrylate, benzyl methacrylate, phenyl methacrylate, combinations thereof, and the like. In other embodiments, the hydrophobic ethylenically unsaturated polymerizable monomer comprises a linear or branched acrylate such as n-butyl (meth)acrylate, isobutyl (meth)acrylate, or combinations thereof.

[0017] Hydrophobic monomers include, for example, 2,4,6-fluorophenyl acrylate, pentafluorophenyl acrylate, hexafluoro-iso-propyl methacrylate, 1H,1H,3H-hexafluorobutyl methacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate, 1H,1H,2H,2H-heptadecafluorodecyl methacrylate (HDFDMA), 1H,1H,5H-octafluoropentyl methacrylate, 2,2,3,3,4,4,5,5,6,6,7,7 -dodecafluoroheptyl acrylate, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,12-heneicosafluorododecyl acrylate, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl methacrylate, 2,2,3,3,4,4,4-heptafluorobutyl acrylate, 2,2,3,3,4,4,4-heptafluorobutyl methacrylate, 2,2,3,4,4,4-hexafluorobutyl acrylate, 2 ,2,3,4,4,4-Hexafluorobutyl methacrylate, 1,1,1,3,3,3-Hexafluoroisopropyl acrylate, 1,1,1,3,3,3-Hexafluoroisopropyl methacrylate, 2,2,3,3,4,4,5,5-Octafluoropentyl methacrylate, 2,2,3,3,3-Pentafluoropropyl acrylate, 2,2,3,3,3-Pentafluoropropyl methacrylate, 1H,1H,2H,2H-Perfluorodecyl acrylate, 2,2,3,3-Tetrafluoropropyl methacrylate acrylate, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl acrylate, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 2-[(1′,1′,1′-trifluoro-2′-(trifluoromethyl)-2′-hydroxy)propyl]-3-norbornyl methacrylate, perfluorocyclohexyl(meth)acrylate, and any combination thereof.

[0018] The polymer additive may be composed of any combination of the above hydrophobic, non-crosslinkable monomers in any relative proportion of fluorinated and non-fluorinated monomers. The total amount of hydrophobic, non-crosslinkable monomers contained in the total monomer composition may be about 75 to about 85 weight percent, about 70 to about 90 weight percent, or about 50 to about 92 weight percent.

[0019] The polymeric toner additive also includes a monomer having two or more vinyl groups, in some embodiments two or more vinyl groups. Monomers having two or more vinyl groups suitable for use as crosslinked vinyl-containing monomers include, for example, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2'-bis(4-(acryloxy / diethoxy)phenyl)propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, and the like. Examples of suitable crosslinking agents include acrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis(4-(methacryloxy / diethoxy)phenyl)propane, 2,2'-bis(4-(methacryloxy / polyethoxy)phenyl)propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, divinyl ethers, combinations thereof, and the like. In some embodiments, the crosslinking agent may be fluorinated. Suitable fluorinated crosslinking agents include fluorinated divinyl crosslinkers such as 1,8-divinylperfluoro(octane), 1,6-divinylperfluoro(hexane), and 1,4-divinylperfluoro(butane) and perfluorocyclohexyl(meth)acrylate, combinations thereof, and the like.

[0020] The monomer having two or more vinyl groups is 8 weight percent to 40 weight percent of the polymer resin, about 8 weight percent to about 30 weight percent of the polymer resin, or about 10 weight percent to about 20 weight percent of the polymer resin.

[0021] For some commercially available monomers, the monomer purity is relatively low. For example, commercially available DVB-55 divinylbenzene contains about 55 weight percent divinylbenzene and about 45 weight percent ethylvinylbenzene. Ethylvinylbenzene does not contain two vinyl groups to promote crosslinking, but it copolymerizes with ethylenically unsaturated monomers. Thus, as an example, for a commercially available divinylbenzene with a purity of 55%, the weight percent of divinylbenzene in the final copolymer composition is 0.55 x the weight percent of divinylbenzene added.

[0022] An important parameter for crosslinked polymer particles is the number of crosslinks formed in the polymer particle. For divalent crosslinkers, the number of crosslinks per mole of total polymer is equal to the weight percent of crosslinker in the polymer divided by the molecular weight of the crosslinker, which is like dividing the numerator by the denominator, which is the sum of the weight percent of each monomer divided by the molecular weight of that monomer. The result is the moles of crosslinks per mole of monomer unit, or equivalently, the number of crosslinks per monomer unit. With trivalent crosslinkers, there are two crosslinks per crosslinking unit, so the crosslink density is doubled; with tetravalent crosslinkers, the crosslink density is tripled.

[0023] Crosslink density is an important property because it is a key factor controlling the rigidity of polymer particles, i.e., their resistance to deformation. U.S. Patent Application Publication No. 2020 / 0308328, incorporated herein by reference, showed that a minimum of 20% DVB-55 divinylbenzene crosslinker was required to maintain spherical shape for more than one hour of mixing with developer, simulating the mixing toner would experience in a printer. If the crosslinked polymer particles flatten, they will not retain their functionality upon mixing, leading to poor performance in the printer. A minimum amount of 20 weight percent DVB-55 results in a crosslink density of 0.15 crosslinks per monomer unit, calculated as above. With 15 weight percent DVB-55 added, the crosslink density was 0.11 crosslinks per monomer unit, which was insufficient to maintain spherical particles during one hour of vigorous mixing. On the other hand, with 25 weight percent added DVB-55, the crosslink density was 0.19 crosslinks per monomer unit, which was sufficient to maintain spherical crosslinked particles for at least 2 hours.

[0024] As described above, the polymer additive includes a metal oxide. The metal oxide is selected from the group consisting of silica, titania, and alumina. In embodiments, the weight percent of the metal oxide relative to the polymer latex is from about 1 percent to about 30 percent, from about 5 percent to about 50 percent, or from about 10 percent to about 40 percent. The particle size of the metal oxide ranges from 7 nm to about 120 nm, in embodiments from about 7 nm to 50 nm, and in embodiments from about 7 nm to 20 nm.

[0025] A useful measure of the effectiveness of an added metal oxide is the surface area coverage of that metal oxide on polymer latex particles. Without being limited by theory, it is believed that the primary function of the added metal oxide is to effectively coat the surface of the polymer latex, so that when a polymer additive composed of a metal oxide-coated polymer latex contacts any surface within a printing device, the metal oxide on the surface provides at least some of that contact, thereby changing the surface properties and modifying the performance of the polymer additive. For the metal oxide to effectively coat the organic polymer additive, the primary particle size (D50v) of the metal oxide must be smaller than that of the spherical organic additive. If the metal oxide particles are larger, they will instead be coated by the organic latex. Larger particles have a maximum volume that increases like a cube of their size, so it is desirable to have larger particles as the organic polymer particles. Because organic polymer particles have a lower density than metal oxide particles, a smaller weight percent of organic polymer particles is required than if the metal oxide particles were larger. Furthermore, known methods involving emulsion-polymerized polymer particles have difficulty preparing smaller particle sizes. However, while it is possible to prepare emulsion polymerization particles as small as 25 nm, achieving this small size in a production-scale reactor can be difficult. For larger, suitably crosslinked polymer particles, removing residual monomers when the particle size is greater than 200 nm can be difficult, which can lead to unacceptable softening of the particles due to a depopulation effect, or can present odor or even health concerns. In contrast, low-cost metal oxides can be easily produced in sizes from about 7 nm to about 50 nm. However, producing metal oxide nanoparticles greater than 50 nm is difficult and expensive. In some cases, it is possible to produce metal oxide particles larger than 50 nm; for example, colloidal silica can be produced up to 300 nm or even 500 nm. However, these are more expensive.Additionally, because larger particles tend to be too large to adhere to toner and provide very low toner flow, the best overall performance with metal oxides is actually achieved for particle sizes less than 50 nm, and in some embodiments, less than about 120 nm. Therefore, the most manufacturable and lowest cost results in the use of larger polymer latex particles and smaller metal oxides. While the metal oxide may be spherical, it may also be cubic, hexagonal, tabular, needle-like, plate-like, or any other irregular shape. In these cases, the maximum dimension of the metal oxide particles must be smaller than that of the organic polymer particles.

[0026] Regarding the required size ratio of the smaller metal oxide particles to the larger polymer latex particles, the ratio of the smaller metal oxide D50 size to the larger polymer latex particle D50 size is about 0.035 to about 0.5, about 0.05 to about 0.4, or about 0.06 to about 0.3.

[0027] Mathematically, the general formula for the surface area coverage (SAC%) of smaller metal particles on the surface of larger spherical organic surface additives is given by: %SAC=100·w·D·P / (363·d·p) where D is the D50 average size in nanometers and P is the mass per square meter in grams / cm for the organic polymer particles. 3 is the true density in units of 1 / 2 cm, and for metal oxide particles, d is the D50 average size in nanometers and p is the particle size in grams / cm 3 where is the true density in units of 10 ...

[0028] The effective SAC% of metal oxide particles on organic polymer additive particles is about 1% to about 50%. Below about 1% of the metal oxide particles, the added inorganic particles have little effect on the performance of the organic polymer particles. Above about 50%, the organic polymer particle surface is effectively covered, in that the organic polymer particle surface can no longer contact other surfaces. Therefore, additional metal oxide particle coverage increases the difficulty of particle preparation and the amount of free metal oxide particles that may settle out of the latex, with little change in performance.

[0029] In embodiments, the metal oxide nanoparticles can be treated with a silane coupling agent, for example, an alkylsilane such as hexamethyldisilazane (HMDS) or dimethyldichlorosilane, or other long-chain alkylsilanes such as decyltriethoxysilane or octyltrietheoxysilane, or, for example, an alkylsiloxane such as PDMS (polydimethysiloxane). Primary particle sizes can vary from about 7 nm to about 130 nm. Specific examples of treated silica, its particle size, and treatment details include Wacker HDK (registered trademark) H13TD (16 nm, PDMS), HDK (registered trademark) H13™ (16 nm, HMDS), HDK (registered trademark) H13TX (16 nm, HMDS / PDMS), HDK (registered trademark) H20TD (12 nm, PDMS), HDK (registered trademark) H20™ (12 nm, HMDS), HDK (registered trademark) H20TX (12 nm, HMDS / PDMS), HDK (registered trademark) H30TD (8 nm, PDMS), HDK (registered trademark) H30™ (8 nm, HMDS), HDK (registered trademark) H30TX (8 nm, HMDS / PDMS), HDK (registered trademark) H3004 (12 nm, HMDS), Wacker HDK® HO5TD (40 nm, PDMS), HDK® HO5™ (40 nm, HMDS), HDK® HO5TX (40 nm, HMDS / PDMS); Evonik R972 (16 nm, DDS), RY200S (16 nm, PDMS, BET = 200 m 2 / g), R202 (16 nm, PDMS), R974 (12 nm, DDS), RY200 (12 nm, PDMS), RX200 (12 nm, HMDS), R8200 (12 nm, HMDS), R805 (12 nm, alkylsilane), R104 (12 nm, alkylsilane), RX300 (7 nm, HMDS), R812 (7 nm, HMDS), R812S (7 nm, HMDS, BET = 300 m 2 / g), R106 (7 nm, alkylsilane), NY50 (30 nm, PDMS), NAX50 (30 nm, HMDS), RY50 (40 nm, PDMS), and RX50 (40 nm, HMDS); Cabot TS530 (8 nm, HMDS).

[0030] In embodiments, the oxide may also include treatments, for example, with bases or salts of those bases. Specific commercially available examples include Wacker treated silica HDK® H13TA (16 nm, PDMS-NR2 / NR3 + ), HDK® H30TA (8 nm, PDMS-NR2 / NR3 + HDK (registered trademark) H2015EP (12 nm, PDMS-NR2 / NR3 + HDK (registered trademark) H2050EP (10 nm, PDMS-NR2 / NR3 + HDK (registered trademark) H2150VP (10 nm, PDMS-NR2 / NR3 + HDK (registered trademark) H3050VP (8 nm, PDMS-NR2 / NR3 + ) are listed.

[0031] Suitable untreated silicas include 30 nm Aerosil 50, 40 nm Aerosil OX50, 16 nm Aerosil 130, 12 nm Aerosil 200, 7 nm Aerosil 300, and 7 nm Aerosil 380, all available from Evonik.

[0032] Examples of suitable commercially available treated titanium dioxides include JMT-150IB from Tayca Corp. having a 15 nm primary diameter, JMT2000 from Tayca Corp. having a particle size of 15×15×40 nm, T805 from Evonik having an average primary diameter of about 21 nm, AEROXIDE® TiO2NKT90 from Evonik having an average primary diameter of 12 nm, SMT5103 from Tayca Corporation having an average primary diameter of about 40 nm, STT-100H from Inabata America Corporation having an average primary diameter of about 40 nm, 40 nm silane-treated ST-550 from Titan Kogyo, 10×10×50 nm ST-480A and ST-597 silane-treated titania from Titan Kogyo, 40 nm alcohol-treated STT-65CS 40 nm titania from Titan Kogyo, and 50 nm silicone-treated STT-30 from Titan Kogyo. EHJ titania, and silane coupling agent treated 30 nm ST-30A-1 and 20 nm STT-30S titania from Titan Kogyo. Suitable untreated titanium dioxides include 21 nm P25 and 12 nm TN90, both from Evonik.

[0033] Specific commercially available examples of suitable aluminum oxides include Evonik C805 (13 nm, octylsilane), Aluminum Oxide C (13 nm, untreated), Aeroxide Alu C 100 (10 nm, untreated), Aeroxide Alu C 130 (13 nm, untreated), Cabot SpectrAL 81 (21 nm, untreated), and Cabot SpectrAl 100 (18 nm, untreated).

[0034] Examples of additional suitable oxides include titanates, such as CaTiO3, BaTiO3, MgTiO3, MnTiO3, and SrTiO3, and Al2TiO5. Tin oxides and doped tin oxides, such as tin antimony oxide, are also suitable. Further suitable oxides include ZnO2, CaO, MgO, FeO, CrO, MnO, BeO, Ga2O3, In2O3, Tl2O3, GeO2, SnO, SnO2, PbO, PbO2, As2O3, Sb2O3, Bi2O3, and Fe2O3.

[0035] In embodiments, the metal oxide may be colloidal silica dispersed in water, and therefore not dried, as opposed to the other silicas listed above. Commercially available examples of colloidal silica include SNOWTEX® ST-20L (40-50 nm), SNOWTEX® ST-O (10-20 nm), SNOWTEX® ST-OL (40-50 nm), SNOWTEX® ST-OS (8-11 nm), SNOWTEX® ST-S (8-11 nm), SNOWTEX® ST-AK (10-20 nm), SNOWTEX® ST-O40 (20-30 nm), and SNOWTEX® ST-50 (20-30 nm), all from Nissan Chemical. Other suitable water-dispersed colloidal silicas include 5 nm LUDOX® FM, 7 nm LUDOX® SM, 7 nm LUDOX® SM-AS, 12 nm LUDOX® HS-40, 12 nm LUDOX® HAS, 22 nm TM-40 LUDOX®, 22 nm LUDOX® AS-40, 22 nm LUDOX® TMA, 15 nm LUDOX® PX-30, 20 nm LUDOX® PT-40, and 40 nm LUDOX® PW-50, all available from Grace.

[0036] While it is desirable to use hydrophobic monomers to provide low relative humidity sensitivity for fill, flow, development, and transfer in the printer, in embodiments, some comonomers that are not necessarily hydrophobic can be included, for example, to modify the fill characteristics of the resin latex. The copolymer additives of the present disclosure, when included in polymeric toner additives, can also include monomers having amine functionality. The amine-functional monomers can be derived from acrylates, methacrylates, combinations thereof, and the like. In some embodiments, suitable amine-functional monomers include dimethylaminoethyl methacrylate (DMAEMA), diethylaminoethyl methacrylate, dipropylaminoethyl methacrylate, diisopropylaminoethyl methacrylate, dibutylaminoethyl methacrylate, combinations thereof, and the like.

[0037] The amine-functional monomer may be present in such copolymers in an amount from about 0.1% by weight of the copolymer to about 5% by weight of the copolymer, in embodiments from about 0.5% by weight of the copolymer to about 2% by weight of the copolymer.

[0038] Ethylenically unsaturated monomers having at least one acidic group can also be present as comonomers in the polymeric nanoparticles of the present disclosure. Such ethylenically unsaturated monomers can have pendant carboxylic or sulfonic acids. Illustrative examples include, but are not limited to, maleic acid, methyl hydrogen maleate, ethyl hydrogen maleate, itaconic acid, fumaric acid, crotonic acid, citraconic acid, styrenesulfonic acid, β-carboxyethyl acrylate, acrylic acid, methacrylic acid, and vinyl-derivatized 2-aminomethylpropanesulfonic acid. The carboxylic acid forms of the aforementioned monomers may also be present in esterified forms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, and the like. Other suitable esterified monomers may contain ethylenically unsaturated groups in the alcohol-derived portion of the esterified monomer. Such ethylenically unsaturated monomers can include, for example, vinyl acetate, allyl acetate, vinyl propionate, allyl propionate, vinyl benzoate, allyl benzoate, and the like.

[0039] The acid-functional or esterified acid monomer may be present in such copolymers in an amount up to about 10% by weight of the copolymer, in embodiments from about 0.5% by weight of the copolymer to about 5% by weight of the copolymer, hi embodiments, the acid-functional monomer provides a more negative charge to the polymer latex.

[0040] Methods of forming the polymeric toner additive are within the purview of those skilled in the art and, in embodiments, include emulsion polymerization of the monomers and metal oxides utilized to form the polymeric toner additive.

[0041] In embodiments, the latex for forming the polymeric toner additive may be prepared in an aqueous phase containing a surfactant or co-surfactant, optionally under an inert gas such as nitrogen. The surfactant that may be utilized with the resin to form the latex dispersion may be an ionic or non-ionic surfactant in an amount of from about 0.01 to about 15 percent by weight of solids, in embodiments from about 0.1 to about 10 percent by weight of solids.

[0042] In some embodiments, the charge control agent monomers include nitrogen-containing groups, including, but not limited to, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dipropylaminoethyl methacrylate, diisopropylaminoethyl methacrylate, dibutylaminoethyl methacrylate, and combinations thereof.

[0043] The charge control agent monomer comprises from 0.1% to 1.5%, from about 0.6% to 1.2%, or from about 0.7% to about 1.1% by weight of nitrogen-containing groups in the polymer additive.

[0044] The method of forming the polymeric toner additive, in embodiments, includes emulsion polymerization of the monomers utilized to form the polymeric additive, which is prepared by adding a metal oxide to the monomer mixture prior to emulsion polymerization of the polymer latex.

[0045] In the polymerization process, reactants including a metal oxide, a hydrophobic monomer, and a monomer having two or more vinyl groups may be added to a suitable reactor, such as a mixing vessel. Appropriate amounts of starting materials may optionally be dissolved in a solvent, and an optional initiator may be added to the solution and contacted with at least one surfactant to form an emulsion. A polymer additive may be formed in the emulsion, which may then be recovered and used as a polymer additive for a toner composition.

[0046] If used, suitable solvents include, but are not limited to, water and / or organic solvents such as toluene, benzene, xylene, tetrahydrofuran, acetone, acetonitrile, carbon tetrachloride, chlorobenzene, cyclohexane, diethyl ether, dimethyl ether, dimethylformamide, heptane, hexane, methylene chloride, pentane, combinations thereof, and the like.

[0047] In embodiments, a latex for forming the polymeric toner additive may be prepared in an aqueous phase containing a surfactant or co-surfactant, optionally under an inert gas such as nitrogen. The surfactant may be utilized with the resin to form the latex dispersion and may be an ionic or non-ionic surfactant in an amount of from about 0.01 to about 15 percent by weight of solids, in embodiments from about 0.1 to about 10 percent by weight of solids.

[0048] Anionic surfactants that can be utilized include sulfates and sulfonates, sodium dodecyl sulfate (SDS), also known as sodium lauryl sulfate (SLS), sodium dodecylbenzenesulfonate, sodium dodecylnaphthalene sulfate, dialkylbenzene alkyl sulfates and sulfonates, acids such as abietic acid available from Aldrich, NEOGEN R™ and NEOGEN SC™ from Dai-ichi Kogyo Seiyaku Co., Ltd., combinations thereof, and the like. Other suitable anionic surfactants, in embodiments, include DOWFAX™ 2A1, an alkyldiphenyloxide disulfonate from Dow Chemical Company, and / or Teika Power BN2060 from Teika Corporation (Japan), which are branched sodium dodecylbenzenesulfonates. Combinations of these surfactants with any of the aforementioned anionic surfactants may also be utilized in embodiments.

[0049] Examples of cationic surfactants include, but are not limited to, ammonium, such as alkylbenzyldimethylammonium chloride, dialkylbenzenealkylammonium chloride, lauryltrimethylammonium chloride, alkylbenzylmethylammonium chloride, alkylbenzyldimethylammonium bromide, benzalkonium chloride, C 12 ,C 15 ,C 17trimethylammonium bromide, combinations thereof, etc. Other cationic surfactants include cetylpyridinium bromide, halide salts of quaternized polyoxyethyl alkylamines, dodecylbenzyltriethylammonium chloride, MIRAPOL and ALKAQUAT available from Alkaril Chemical Company, Sanizol (benzalkonium chloride) available from Kao Chemicals, combinations thereof, etc. In some embodiments, suitable cationic surfactants include SANISOL B-50 available from Kao Corp., which is primarily benzyldimethylalkonium chloride.

[0050] Examples of nonionic surfactants include, but are not limited to, alcohols, acids and ethers, such as polyvinyl alcohol, polyacrylic acid, metallose, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, dialkylphenoxypoly(ethyleneoxy)ethanol, combinations thereof, and the like. In some embodiments, surfactants commercially available from Rhone-Poulenc may be utilized, such as IGEPAL CA-210™, IGEPAL CA-520™, IGEPAL CA-720™, IGEPAL CO-890™, IGEPAL CO-720™, IGEPAL CO-290™, IGEPAL CA-210™, ANTAROX 890™, and ANTAROX 897™.

[0051] The selection of a particular surfactant or combination thereof, as well as the amount of each to use, is within the knowledge of one skilled in the art.

[0052] In embodiments, an initiator may be added to form the latex utilized in forming the polymeric toner additive. Examples of suitable initiators include water-soluble initiators, such as ammonium persulfate, sodium persulfate, and potassium persulfate, and organic solvent-soluble initiators, including organic peroxides, and azo compounds, including Vazo peroxides, such as VAZO 64™, 2-methyl-2-2′-azobispropanenitrile, VAZO 88™, 2-2′-azobisisobutyramide anhydride, and combinations thereof. Other water-soluble initiators that can be utilized include azoamidine compounds such as 2,2'-azobis(2-methyl-N-phenylpropionamidine) dihydrochloride, 2,2'-azobis[N-(4-chlorophenyl)-2-methylpropionamidine] dihydrochloride, 2,2'-azobis[N-(4-hydroxyphenyl)-2-methyl-propionamidine] dihydrochloride, 2,2'-azobis[N-(4-amino-phenyl)-2-methylpropionamidine] tetrahydrochloride, 2,2'-azobis[2-methyl-N(phenylmethyl)propionamidine] dihydrochloride, 2,2'-azobis[2-methyl-N-2-propenylpropionamidine] dihydrochloride, 2,2'-azobis[N-(2-hydroxy-ethyl)-2-methylpropionamidine] amidine] dihydrochloride, 2,2'-azobis[2(5-methyl-2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis[2-(4,5,6,7-tetrahydro-1H-1,3-diazepin-2-yl)propane] dihydrochloride, 2,2'-azobis[2- (3,4,5,6-tetrahydropyrimidin-2-yl)propane] dihydrochloride, 2,2'-azobis[2-(5-hydroxy-3,4,5,6-tetrahydropyrimidin-2-yl)propane] dihydrochloride, 2,2'-azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane} dihydrochloride, and combinations thereof.

[0053] The initiator may be added in a suitable amount, for example, from about 0.1 to about 8 weight percent, and in embodiments from about 0.2 to about 5 weight percent of the monomers.

[0054] In forming an emulsion containing a metal oxide, the starting materials, surfactant, optional solvent, and optional initiator can be combined using any means within the purview of one skilled in the art. In some embodiments, the reaction mixture may be mixed for about 1 minute to about 72 hours, and in certain embodiments, for about 4 hours to about 24 hours, while maintaining a temperature of about 10° C. to about 100° C., in certain embodiments, about 20° C. to about 90° C., and in other certain embodiments, about 45° C. to about 75° C.

[0055] Those skilled in the art will understand that optimization of reaction conditions, temperatures, and initiator loadings can be varied to produce polymers of various molecular weights, and that equivalent techniques can be used to polymerize structurally related starting materials.

[0056] The average particle size measurements of the polymer toner additives were measured by dynamic light scattering using a Nanotrac 252 instrument (Microtrac, Inc.).

[0057] As used herein, the term "average particle size" refers to the diameter value where 50% of the particles in a sample (by volume unless otherwise specified) have a diameter less than that value. Average particle size may also be referred to as "D50."

[0058] The particle size of polymer toner particles ranging in size from 0.0008 to 6.54 micrometers is measured using a Nanotrac 252 instrument. This instrument uses laser light scattering technology to measure the Doppler shift of light generated from each particle in motion (Brownian motion). These shifts generate a signal proportional to the particle size. The signal is mathematically converted to particle size and size distribution. Analysis can be performed using an external probe or by inserting the probe into a fixed sample chamber.

[0059] For light scattering techniques, NIST polystyrene nanosphere control samples with diameters in the range of 15 nm to 150 nm, available from Microtrac under the trade name NIST Traceable Reference Material for Nanotrac Particle Size Analyzers, can be used.

[0060] The resulting polymeric toner additive particles of the present disclosure may be applied to toner particles utilizing any means within the purview of those skilled in the art. In some embodiments, the toner particles may be dipped into or sprayed with the polymeric additive particles, thus coating the surface of the toner particles, and the coated particles may then be dried.

[0061] In other embodiments, once the polymeric toner additive particles are formed, they may be recovered from the reactor by any technique within the purview of those skilled in the art, including filtration, drying, centrifugation, spray drying, combinations thereof, and the like.

[0062] In some embodiments, once obtained, the polymeric toner additive particles may be dried to a powder form by any method within the purview of those skilled in the art, including, for example, freeze drying, spray drying, optionally in a vacuum, combinations thereof, etc. The dried polymeric toner additive particles of the present disclosure may then be applied to toner particles utilizing any means within the purview of those skilled in the art, including, but not limited to, mechanical impact and / or electrostatic attraction. An example of a mechanical mixing device is a Henschel FM high intensity mixer from Zeppelin Systems, although other mixing devices may also be used in embodiments.

[0063] The particles of the polymeric toner additive particles may have an average or medium particle size (D50) of from about 20 nanometers to about 200 nanometers in diameter, in embodiments from about 40 nanometers to about 150 nanometers in diameter.

[0064] In embodiments, the polymeric additive utilized in the polymeric toner additive particles, which may be soluble in a solvent such as tetrahydrofuran (THF), has a number average molecular weight (M), as measured by gel permeation chromatography (GPC), for example, of from about 40,000 to about 280,000 daltons, in embodiments, from about 60,000 to about 170,000 daltons. n ), and a weight average molecular weight (M), for example, of about 200,000 to about 800,000 daltons, in embodiments, of about 400,000 to about 600,000 daltons, as measured by gel permeation chromatography using polystyrene standards. w In some embodiments, the crosslinking may limit the solubility of the crosslinked resin, making it impossible to measure the molecular weight by any method.

[0065] The polymer or polymer additive utilized in the polymeric toner additive particles may have a glass transition temperature (Tg) of from about 85° C. to about 140° C., in embodiments from about 100° C. to about 130° C. In some embodiments, it may be impossible to determine the Tg due to crosslinking of the resin, which may make detection of the Tg difficult. In some embodiments, the A-zone charge of toners including polymeric additives of the present disclosure may be from about −15 to about −80 microcoulombs per gram, in embodiments from about −20 to about −60 microcoulombs per gram, while the C-zone charge of toners including polymeric additives of the present disclosure may be from about −15 to about −80 microcoulombs per gram, in embodiments from about −20 to about −60 microcoulombs per gram.

[0066] The polymeric toner additive particles of the present disclosure may be combined with the toner particles such that the polymeric toner additive particles are present in an amount from about 0.1% by weight of the toner particles to about 5% by weight of the toner particles, in embodiments from about 0.2% by weight of the toner particles to about 2% by weight of the toner particles.

[0067] Thus, the polymeric toner additive particles of the present disclosure can be utilized in a number of different combinations to formulate developers with selected high triboelectric charging properties and / or conductivity values. toner

[0068] The polymeric toner additive particles so produced may then be combined with a toner resin, optionally with a colorant, to form a toner of the present disclosure. resin

[0069] Any toner resin can be utilized in forming the toner of the present disclosure. Such resins may then be made with any suitable monomer or monomers by any suitable polymerization method. In embodiments, the resins may be prepared by methods other than emulsion polymerization. In further embodiments, the resins may be prepared by condensation polymerization.

[0070] The toner compositions of the present disclosure, in embodiments, include an amorphous resin. The amorphous resin may be linear or branched. In embodiments, the amorphous resin may include at least one low molecular weight amorphous polyester resin. Low molecular weight amorphous polyester resins, available from a number of sources, may have a variety of glass transition temperatures, for example, from about 30° C. to about 80° C., in embodiments, from about 35° C. to about 75° C. As used herein, a low molecular weight amorphous polyester resin has a number average molecular weight (M), for example, as measured by gel permeation chromatography (GPC), of from about 1,000 to about 10,000, in embodiments, from about 2,000 to about 8,000, in embodiments, from about 3,000 to about 7,000, and in embodiments, from about 4,000 to about 6,000. n The weight average molecular weight (M w ) is 50,000 or less, for example, in embodiments, from about 2,000 to about 50,000, in embodiments, from about 3,000 to about 40,000, in embodiments, from about 10,000 to about 30,000, and in embodiments, from about 18,000 to about 21,000, as determined by GPC using polystyrene standards.w / M n ) is, for example, from about 2 to about 6, and in embodiments, from about 3 to about 4. The low molecular weight amorphous polyester resin may have an acid number of from about 8 to about 20 mg KOH / g, and in embodiments, from about 9 to about 16 mg KOH / g, and in embodiments, from about 10 to about 14 mg KOH / g.

[0071] Examples of linear amorphous polyester resins that can be utilized include poly(propoxylated bisphenol A co-fumarate), poly(ethoxylated bisphenol A co-fumarate), poly(butyloxylated bisphenol A co-fumarate), poly(co-propoxylated bisphenol A co-ethoxylated bisphenol A co-fumarate), poly(1,2-propylene fumarate), poly(propoxylated bisphenol A co-maleate), poly(ethoxylated bisphenol A co-maleate), poly(butyl ... Poly(1,2-propylene itaconate), poly(butylenated bisphenol A coitaconate), poly(copropoxylated bisphenol A coethoxylated bisphenol A co-maleate), poly(1,2-propylene itaconate), poly(propoxylated bisphenol A coitaconate), poly(ethoxylated bisphenol A coitaconate), poly(butylenated bisphenol A coitaconate), poly(copropoxylated bisphenol A coethoxylated bisphenol A coitaconate), poly(1,2-propylene itaconate), and combinations thereof.

[0072] In some embodiments, suitable amorphous resins may include alkoxylated bisphenol A fumarate / terephthalate based polyester and copolyester resins. In some embodiments, a suitable amorphous polyester resin may be a copoly(propoxylated bisphenol A co-fumarate)-copoly(propoxylated bisphenol A co-terephthalate) resin having the following formula (I): [ka] wherein R may be hydrogen or a methyl group, m and n represent random units of the polymer additive, and m may be about 2 to 10, and n may be about 2 to 10. Examples of such resins and processes for their production include those disclosed in U.S. Pat. No. 6,063,827, the disclosure of which is incorporated herein by reference in its entirety.

[0073] In some embodiments, the low molecular weight amorphous polyester resin may be a saturated or unsaturated amorphous polyester resin. Illustrative examples of saturated and unsaturated amorphous polyester resins selected for the processes and particles of the present disclosure include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polypentylene terephthalate, polyhexylene terephthalate, polyheptadene terephthalate, polyoctalene terephthalate, polyethylene isophthalate, polypropylene isophthalate, polybutylene isophthalate, polypentylene isophthalate, and polyhexylene isophthalate. , Polyheptadene-isophthalate, Polyoctalene-isophthalate, Polyethylene-sebacate, Polypropylene-sebacate, Polybutylene-sebacate, Polyethylene-adipate, Polypropylene-adipate, Polybutylene-adipate, Polypentylene-adipate, Polyhexylene-adipate, Polyheptadene-adipate, Polyoctalene-adipate, Polyethylene-glutarate, Polypropylene-glutarate, Polybutylene-glutarate, Polypentylene-glutarate, Polyhexylene- Glutarate, polyheptadene-glutarate, polyoctalene-glutarate, polyethylene-pimelate, polypropylene-pimelate, polybutylene-pimelate, polypentylene-pimelate, polyhexylene-pimelate, polyheptadene-pimelate, poly(ethoxylated bisphenol A-fumarate), poly(ethoxylated bisphenol A-succinate), poly(ethoxylated bisphenol A-adipate), poly(ethoxylated bisphenol A-glutarate), poly(ethoxylated bisphenol A) bisphenol A-terephthalate), poly(ethoxylated bisphenol A-isophthalate), poly(ethoxylated bisphenol A-dodecenyl succinate), poly(propoxylated bisphenol A-fumarate), poly(propoxylated bisphenol A-succinate), poly(propoxylated bisphenol A-adipate), poly(propoxylated bisphenol A-glutarate), poly(propoxylated bisphenol A-terephthalate), poly(propoxylated bisphenol A-isophthalate),Examples of suitable amorphous polyesters include poly(propoxylated bisphenol A-dodecenyl succinate), SPAR (Dixie Chemicals), BECKOSOL (Reichhold Inc.), ARAKOTE (Ciba-Geigy Corporation), HETRON (Ashland Chemical), PARAPLEX (Rohm & Haas), POLYLITE (Reichhold Inc.), PLASTHALL (Rohm & Haas), CYGAL (American Cyanamide), ARMCO (Armco Composites), ARPOL (Ashland Chemical), CELANEX (Celanese Eng), RYNITE (DuPont), STYPOL (Freeman Chemical Corporation), and combinations thereof. Resins may also be functionalized, such as by carboxylation, sulfonation, or sodium sulfonation, if desired.

[0074] Examples of suitable polycondensation catalysts for any of the low molecular weight amorphous polyester resins include tetraalkyl titanates, dialkyl tin oxides such as dibutyltin oxide, tetraalkyl tins such as dibutyltin dilaurate, dialkyl tin oxide hydroxides such as butyltin oxide hydroxide, aluminum alkoxides, alkyl zincs, dialkyl zincs, zinc oxide, stannous oxide, or mixtures thereof, which may be utilized in amounts of, for example, from about 0.01 mol % to about 5 mol % based on the starting diacid or diester used to produce the polyester resin.

[0075] The low molecular weight amorphous polyester resin may be a branched resin. As used herein, the terms "branched" or "branched" include branched and / or crosslinked resins.

[0076] The resulting unsaturated polyester is reactive (e.g., crosslinkable) at two fronts: (i) the sites of unsaturation (double bonds) along the polyester chain, and (ii) functional groups suitable for acid-base reactions, such as carboxyl groups, hydroxyl groups, etc. In some embodiments, the unsaturated polyester resins are prepared by melt polycondensation or other polymerization processes using diacids and / or anhydrides and diols.

[0077] In some embodiments, the low molecular weight amorphous polyester resin or combination of low molecular weight amorphous resins may have a glass transition temperature of from about 30° C. to about 80° C., in embodiments from about 35° C. to about 70° C. In further embodiments, the combined amorphous resins may have a glass transition temperature of from about 10 to about 1,000,000 Pa at about 130° C. * S, in embodiments, about 50 to about 100,000 Pa * It may have a melt viscosity of S.

[0078] The amount of low molecular weight amorphous polyester resin in the toner particles of the present disclosure may be present in any core, any shell, or both, in an amount of from 25 to about 50% by weight, in embodiments from about 30 to about 45% by weight, and in embodiments from about 35 to about 43% by weight of the toner particles (i.e., toner particles excluding external additives and water).

[0079] In some embodiments, the toner composition comprises at least one crystalline resin. As used herein, "crystalline" refers to a polyester having three-dimensional order. As used herein, "semi-crystalline resin" refers to a resin having a crystallinity of, for example, about 10 to about 90%, in embodiments, about 12 to about 70%. Furthermore, as used hereinafter, "crystalline polyester resin" and "crystalline resin" encompass both crystalline and semi-crystalline resins unless otherwise specified.

[0080] In some embodiments, the crystalline polyester resin is a saturated crystalline polyester resin or an unsaturated crystalline polyester resin.

[0081] Crystalline polyester resins available from many sources may have a variety of melting points, for example, from about 30° C. to about 120° C., in embodiments, from about 50° C. to about 90° C. The crystalline resins may have a number average molecular weight (M), for example, as measured by gel permeation chromatography (GPC), of from about 1,000 to about 50,000, in embodiments, from about 2,000 to about 25,000, in embodiments, from about 3,000 to about 15,000, and in embodiments, from about 6,000 to about 12,000. n The molecular weight distribution (M w / M n ) is, for example, from about 2 to about 6, and in embodiments, from about 3 to about 4. The crystalline polyester resin may have an acid value of from about 2 to about 20 mg KOH / g, and in embodiments, from about 5 to about 15 mg KOH / g, and in embodiments, from about 8 to about 13 mg KOH / g.

[0082] Illustrative examples of crystalline polyester resins include 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(octylene succinate), poly(ethylene sebacate), poly(propylene sebacate), poly(ethylene sebacate), poly(propylene sebacate), poly(ethylene succinate), poly(ethylene succinate), poly(propylene succinate), poly(butylene succinate), poly(pentylene succinate), poly(hexylene succinate), poly(octylene succinate), poly(ethylene sebacate), poly(propylene sebacate), poly(ethylene sebacate), poly(ethylene succinate ... Poly(butylene sebacate), poly(pentylene sebacate), poly(hexylene sebacate), poly(octylene sebacate), poly(nonylene sebacate), poly(decylene sebacate), poly(undecylene sebacate), poly(dodecylene sebacate), poly(ethylene dodecanedioate), poly(propylene dodecanedioate), poly(butylene dodecanedioate), poly(pentylene dodecanedioate), poly(hexylene dodecanedioate), poly(octylene dodecanedioate) t), poly(nonylene-dodecanedioate), poly(decylene-dodecanedioate), poly(undecylene-dodecanedioate), poly(dodecylene-dodecanedioate), poly(ethylene-fumarate), poly(propylene-fumarate), poly(butylene-fumarate), poly(pentylene-fumarate), poly(hexylene-fumarate), poly(octylene-fumarate), poly(nonylene-fumarate), poly(decylene-fumarate), copoly(5-sulfoisophthaloyl)-copoly(ethylene-adipate), copoly( 5-sulfoisophthaloyl)-copoly(propylene adipate), copoly(5-sulfoisophthaloyl)-copoly(butylene adipate), copoly(5-sulfoisophthaloyl)-copoly(pentylene adipate), copoly(5-sulfoisophthaloyl)-copoly(hexylene adipate), copoly(5-sulfoisophthaloyl)-copoly(octylene adipate), copoly(5-sulfoisophthaloyl)-copoly(ethylene adipate), copoly(5-sulfoisophthaloyl)-copoly(propylene adipate),Copoly(5-sulfoisophthaloyl)-copoly(butylene-adipate), copoly(5-sulfoisophthaloyl)-copoly(pentylene-adipate), copoly(5-sulfoisophthaloyl)-copoly(hexylene-adipate), copoly(5-sulfoisophthaloyl)-copoly(octylene-adipate), copoly(5-sulfoisophthaloyl)-copoly(ethylene-succinate), copoly(5-sulfoisophthaloyl)-copoly( propylene succinate), copoly(5-sulfoisophthaloyl)-copoly(butylene succinate), copoly(5-sulfoisophthaloyl)-copoly(pentylene succinate), copoly(5-sulfoisophthaloyl)-copoly(hexylene succinate), copoly(5-sulfoisophthaloyl)-copoly(octylene succinate), copoly(5-sulfoisophthaloyl)-copoly(ethylene sebacate), copoly(5-sulfoisophthaloyl)-copoly(ethylene sebacate), copoly(5-sulfoisophthaloyl)-copoly(ethylene succinate ... copoly(5-sulfo-isophthaloyl)-copoly(propylene sebacate), copoly(5-sulfo-isophthaloyl)-copoly(butylene sebacate), copoly(5-sulfo-isophthaloyl)-copoly(pentylene sebacate), copoly(5-sulfo-isophthaloyl)-copoly(hexylene sebacate), copoly(5-sulfo-isophthaloyl)-copoly(octylene sebacate), copoly(5-sulfo-isophthaloyl)

[0033] Examples of the crystalline polyester include any of a variety of crystalline polyesters, such as copoly(ethylene adipate), copoly(5-sulfoisophthaloyl)-copoly(propylene adipate), copoly(5-sulfoisophthaloyl)-copoly(butylene adipate), copoly(5-sulfoisophthaloyl)-copoly(pentylene adipate), copoly(5-sulfoisophthaloyl)-copoly(hexylene adipate), and combinations thereof.

[0083] The crystalline resins can be prepared by a polycondensation process by reacting a suitable organic diol with a suitable organic diacid in the presence of a polycondensation catalyst.

[0084] Examples of organic diols selected for preparing the crystalline polyester resin include aliphatic diols having from about 2 to about 36 carbon atoms.

[0085] Examples of organic diacids or diesters selected for preparing the crystalline polyester resin include oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, cyclohexanedicarboxylic acid, malonic acid, and mesaconic acid, their diesters, or anhydrides thereof; and alkali sulfo-organic diacids, such as dimethyl-5-sulfo-isophthalate, dialkyl-5-sulfo-isophthalate-4-sulfo-1,8-naphthalic acid, and the like. Examples of suitable diacids include sodium, lithium, or potassium salts of sulfophthalic acid, 4-sulfophthalic acid, dimethyl-4-sulfophthalate, dialkyl-4-sulfophthalates, 4-sulfophenyl-3,5-dicarbomethoxybenzene, 6-sulfo-2-naphthyl-3,5-dicarbomethoxybenzene, sulfoterephthalic acid, dimethyl-sulfoterephthalate, 5-sulfoisophthalic acid, dialkyl-sulfoterephthalates, sulfo-p-hydroxybenzoic acid, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate, or mixtures thereof. The organic diacid is selected, for example, in an amount of about 40 to about 50 mole percent of the resin, and the alkali sulfoaliphatic diacid can be selected in an amount of about 1 to about 10 mole percent of the resin.

[0086] In some embodiments, suitable crystalline resins may include resins comprised of ethylene glycol or nonanediol and a mixture of dodecanedioic acid and fumaric acid comonomers having the following formula (II): [ka] In the formula, b is about 5 to about 2,000, and d is about 5 to about 2,000.

[0087] As used herein, semi-crystalline polyester resins include poly(3-methyl-1-butene), poly(hexamethylene carbonate), poly(ethylene-p-carboxyphenoxy-butyrate), poly(ethylene-vinyl acetate), poly(docosyl acrylate), poly(dodecyl acrylate), poly(octadecyl acrylate), poly(octadecyl methacrylate), poly(behenyl polyethoxyethyl methacrylate), poly(ethylene adipate), poly(decamethylene adipate), poly(decamethylene azelaate), poly(hexamethylene oxalate), poly(decamethylene oxalate), poly(ethylene oxide), poly(propylene oxide), poly(butadiene oxide), poly(decamethylene oxide), poly(decamethylene sulfide), poly(decamethylene disulfide), poly(ethylene sebacatenol), poly(ethylene olefin copolymer ... ate), poly(decamethylene sebacate), poly(ethylene suberate), poly(decamethylene succinate, poly(eicosamethylene malonate), poly(ethylene-p-carboxyphenoxy-undecanoate), poly(ethylene dithionesophthalate), poly(methylethylene terephthalate), poly(ethylene-p-carboxyphenoxy-valerate), poly(hexamethylene-4,4'-oxydibenzoate), poly Poly(10-hydroxycapric acid), poly(isophthalaldehyde), poly(octamethylene dodecanedioate), poly(dimethylsiloxane), poly(dipropylsiloxane), poly(tetramethylene phenylene diacetate), poly(tetramethylene trithiodicarboxylate), poly(trimethylene dodecanedioate), poly(m-xylylene), poly(p-xylylene pimelamide), and combinations thereof.

[0088] The amount of crystalline polyester resin in the toner particles of the present disclosure may be present in the core, shell, or both, in an amount of from 1 to about 15% by weight, in embodiments from about 5 to about 10% by weight, and in embodiments from about 6 to about 8% by weight of the toner particles (i.e., toner particles excluding external additives and water).

[0089] In embodiments, toners of the present disclosure may also include at least one high molecular weight branched or crosslinked amorphous polyester resin. The high molecular weight resin may, in embodiments, include, for example, a branched amorphous resin or amorphous polyester, a crosslinked amorphous resin or amorphous polyester, or a mixture thereof, or a crosslinked, non-crosslinked amorphous polyester resin. According to the present disclosure, from about 1% to about 100% by weight of the high molecular weight amorphous polyester resin may be branched or crosslinked, and in embodiments, from about 2% to about 50% by weight of the high molecular weight amorphous polyester resin may be branched or crosslinked.

[0090] As used herein, a high molecular weight amorphous polyester resin is a polyester having, for example, a number average molecular weight (M) of about 1,000 to about 10,000 as measured by, for example, gel permeation chromatography (GPC). n High molecular weight amorphous resins available from a number of sources may have a variety of glass transition onset temperatures (Tg), as measured by differential scanning calorimetry (DSC), for example, from about 40° C. to about 80° C., in embodiments from about 50° C. to about 70° C., and in embodiments from about 54° C. to about 68° C. In embodiments, the linear and branched amorphous polyester resins may be saturated or unsaturated resins.

[0091] High molecular weight amorphous polyester resins can be prepared by branching or crosslinking linear polyester resins. Branching agents, such as trifunctional or polyfunctional monomers, can be used, and these agents typically increase the molecular weight and polydispersity of the polyester. Suitable branching agents include glycerol, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, diglycerol, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, and combinations thereof. These branching agents can be used in effective amounts of about 0.1 mol % to about 20 mol %, based on the starting diacid or diester used to make the resin.

[0092] In some embodiments, crosslinked polyester resins can be made from linear amorphous polyester resins containing unsaturated sites capable of reacting under free radical conditions. In some embodiments, suitable unsaturated polyester resins can be prepared from diacids and / or anhydrides, such as, for example, maleic anhydride, terephthalic acid, trimellitic acid, fumaric acid, and the like, and combinations thereof, and diols, such as, for example, bisphenol A ethylene oxide adducts, bisphenol A propylene oxide adducts, and the like, and combinations thereof. In some embodiments, a suitable polyester is poly(propoxylated bisphenol A co-fumaric acid).

[0093] In some embodiments, crosslinked branched polyesters may be utilized as high molecular weight amorphous polyester resins. Examples of such polyesters and their synthesis methods include those disclosed in U.S. Patent No. 6,592,913, the disclosure of which is incorporated herein by reference in its entirety.

[0094] Suitable polyols may contain from about 2 to about 100 carbon atoms and have at least two or more hydroxyl groups, or esters thereof. Polyols may include glycerol, pentaerythritol, polyglycols, polyglycerols, and the like, or mixtures thereof. The polyol may include glycerol. Suitable esters of glycerol include glycerol palmitate, glycerol sebacate, glycerol adipate, triacetin tripropionin, and the like. The polyol may be present in an amount of from about 20% to about 30% by weight of the reaction mixture, in embodiments from about 22% to about 26% by weight of the reaction mixture.

[0095] In some embodiments, the crosslinked branched polyester of the high molecular weight amorphous polyester resin may include that resulting from the reaction of dimethyl terephthalate, 1,3-butanediol, 1,2-propanediol, and pentaerythritol.

[0096] In embodiments, a high molecular weight resin, such as a branched polyester, may be present on the surface of the toner particles of the present disclosure. The high molecular weight resin on the surface of the toner particles may also be particulate in nature, and may be high molecular weight resin particles having diameters of from about 100 nanometers to about 300 nanometers, in embodiments from about 110 nanometers to about 150 nanometers.

[0097] The amount of high molecular weight amorphous polyester resin in the toner particles of the present disclosure, in any core, any shell, or both, may be from about 25% to about 50% by weight of the toner, in embodiments from about 30% to about 45% by weight, and in other embodiments, alternatively from about 40% to about 43% by weight of the toner (i.e., toner particles excluding external additives and water).

[0098] The ratio of crystalline resin to low molecular weight amorphous resin to high molecular weight amorphous polyester resin may range from about 1:1:98 to about 98:1:1 to about 1:98:1, in embodiments from about 1:5:5 to about 1:9:9, in embodiments from about 1:6:6 to about 1:8:8. surfactants

[0099] In embodiments, the resins, waxes, and other additives used to form the toner composition may be in a dispersion including a surfactant. Additionally, the toner particles may be formed by emulsion aggregation techniques in which the resin and other components of the toner are placed in one or more surfactants to form an emulsion, and the toner particles are aggregated, coalesced, and optionally washed, dried, and recovered.

[0100] One, two, or more surfactants may be utilized. Surfactants may be selected from ionic surfactants and nonionic surfactants. Anionic surfactants and cationic surfactants are encompassed by the term "ionic surfactant." In embodiments, surfactants may be utilized in an amount of from about 0.01% to about 5% by weight of the toner composition, such as from about 0.75% to about 4% by weight of the toner composition, in embodiments from about 1% to about 3% by weight of the toner composition.

[0101] Examples of nonionic surfactants that can be utilized include, for example, polyacrylic acid, metallose, methylcellulose, ethylcellulose, propylcellulose, hydroxyethylcellulose, carboxymethylcellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, dialkylphenoxypoly(ethyleneoxy)ethanol, IGEPAL CA-210™, IGEPAL CA-520™, IGEPAL CA-720™, IGEPAL CO-890™, IGEPAL CO-720™, IGEPAL CO-290™, IGEPAL CA-210™, ANTAROX 890™, and ANTAROX 897™ available from Rhone-Poulenc. Other examples of suitable nonionic surfactants include block copolymers of polyethylene oxide and polypropylene oxide, including those commercially available as Synperonic PE / F, in some embodiments, Synperonic PE / F 108.

[0102] Anionic surfactants that can be utilized include those previously described. Examples of cationic surfactants include those mentioned above. coloring agent

[0103] The latex particles produced as described above can be added to a colorant to produce a toner. In some embodiments, the colorant may be in a dispersion. The colorant dispersion may include submicron colorant particles having a volume average diameter of, for example, about 50 to about 500 nanometers, in embodiments about 100 to about 400 nanometers. The colorant particles may be suspended in an aqueous phase containing an anionic surfactant, a nonionic surfactant, or a combination thereof. Suitable surfactants include any of the surfactants described above. In some embodiments, the surfactant may be ionic and may be present in the dispersion in an amount of about 0.1 to about 25% by weight of the colorant, in embodiments about 1 to about 15% by weight of the colorant.

[0104] Colorants useful in forming toners according to the present disclosure include pigments, dyes, mixtures of pigments and dyes, mixtures of pigments, mixtures of dyes, etc. The colorant may be, for example, carbon black, cyan, yellow, magenta, red, orange, brown, green, blue, violet, or mixtures thereof.

[0105] In embodiments where the colorant is a pigment, the pigment may be, for example, carbon black, phthalocyanine, quinacridone or Rhodamine B™ type, red, green, orange, brown, violet, yellow, fluorescent colorants, and the like.

[0106] The resulting latex in the dispersion, and the colorant dispersion, may be optionally stirred and heated to a temperature of from about 35°C to about 70°C, in embodiments from about 40°C to about 65°C, which may result in toner aggregates having a volume average diameter of from about 2 micrometers to about 10 micrometers, in embodiments from about 5 micrometers to about 8 micrometers. wax

[0107] Optionally, a wax may also be combined with the resin to form the toner particles. If included, the wax may be present in an amount of, for example, from about 1% to about 25% by weight of the toner particles, in embodiments from about 5% to about 20% by weight of the toner particles.

[0108] Examples of waxes that can be selected include waxes having a weight-average molecular weight of about 500 to about 20,000, and in embodiments, about 1,000 to about 10,000. Examples of waxes that can be used include polyolefins such as polyethylene, polypropylene, and polybutene wax; vegetable waxes such as carnauba wax, rice wax, candelilla wax, Japan wax, and jojoba oil; animal waxes such as beeswax; mineral waxes and petroleum waxes such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, and Fischer-Tropsch wax; ester waxes obtained from higher fatty acids and higher alcohols such as stearyl stearate and behenyl behenate; butyl stearate; propyl oleate; Examples of such waxes include ester waxes obtained from higher fatty acids and monohydric or polyhydric lower alcohols, such as glyceride monostearate, glyceride distearate, and pentaerythritol tetrabehenate; ester waxes obtained from higher fatty acids and polyhydric alcohol multimers, such as diethylene glycol monostearate, dipropylene glycol distearate, diglyceryl distearate, and triglyceryl tetrastearate; sorbitan higher fatty acid ester waxes, such as sorbitan monostearate; and cholesterol higher fatty acid ester waxes, such as cholesteryl stearate. Toner Preparation

[0109] Toner particles may be prepared by any method within the purview of those skilled in the art. Although embodiments relating to the manufacture of toner particles are described below with respect to emulsion aggregation processes, any suitable method for preparing toner particles may be used, including chemical processes such as suspension and encapsulation methods disclosed in U.S. Patent Nos. 5,290,654 and 5,302,486, the disclosures of each of which are incorporated herein by reference in their entireties. In embodiments, toner compositions and toner particles may be prepared by an aggregation and coalescence process, in which small resin particles are aggregated to the appropriate toner particle size and then coalesced to achieve the final toner particle shape and morphology.

[0110] In some embodiments, the toner composition may be prepared by an emulsion aggregation process, such as a process comprising aggregating an emulsion containing the resin described above, optionally in a surfactant, with a mixture of optional waxes and any other desired or required additives, and then coalescing the aggregated mixture. The mixture may be prepared by adding optional waxes or other materials (which may be in dispersion(s) optionally containing surfactants) to the emulsion (which may be a mixture of two or more emulsions containing the resin). The pH of the resulting mixture may be adjusted with an acid, such as acetic acid or nitric acid. In some embodiments, the pH of the mixture may be adjusted to about 2 to about 4.5. Additionally, in some embodiments, the mixture may be homogenized. If the mixture is homogenized, homogenization may be achieved by mixing at about 600 to about 6,000 revolutions per minute. Homogenization may be achieved by any suitable means, including, for example, an IKA ULTRA TURRAX T50 probe homogenizer.

[0111] Following preparation of the mixture, a coagulant may be added to the mixture. Any suitable coagulant may be utilized to form the toner. Suitable coagulants include, for example, aqueous solutions of divalent or polyvalent cation materials. Examples of suitable coagulants include polyaluminum halides, such as polyaluminum chloride (PAC), or the corresponding bromides, fluorides, or iodides; polyaluminum silicates, such as polyaluminum sulfosilicate (PASS); and water-soluble metal salts, including aluminum chloride, aluminum nitrite, aluminum sulfate, calcium chloride, calcium nitrite, calcium oxyacids, calcium sulfate, magnesium acetate, magnesium nitrate, magnesium sulfate, zinc acetate, zinc nitrate, zinc sulfate, zinc chloride, zinc bromide, magnesium bromide, copper chloride, copper sulfate, and combinations thereof. In some embodiments, the coagulant may be added to the mixture at a temperature below the glass transition temperature (Tg) of the resin.

[0112] The aggregating agent may be added to the mixture utilized to form the toner in an amount of from about 0.1% to about 8% by weight, in embodiments from about 0.2% to about 5% by weight, and in other embodiments from about 0.5% to about 5% by weight of the resin in the mixture, which provides a sufficient amount of agent for aggregation. Shell Resin

[0113] In some embodiments, a shell may be applied to the aggregated particles after aggregation but before coalescence.

[0114] Resins that can be used to form the shell include, but are not limited to, the amorphous resins described above for use in the core. Such amorphous resins can be low molecular weight resins, high molecular weight resins, or combinations thereof. In some embodiments, amorphous resins that can be used to form the shell according to the present disclosure can include amorphous polyesters of Formula I described above.

[0115] In some embodiments, the amorphous resin used to form the shell may be crosslinked. For example, crosslinking may be achieved by combining the amorphous resin with a crosslinking agent, sometimes referred to herein in embodiments as an initiator. Examples of suitable crosslinking agents include, but are not limited to, free radical or thermal initiators, such as the organic peroxides and azo compounds described above, suitable for forming a gel within the core.

[0116] The crosslinker and amorphous resin may be combined for a time and at a temperature sufficient to form a crosslinked polyester gel. In some embodiments, the crosslinker and amorphous resin may be heated to a temperature of from about 25° C. to about 99° C., in embodiments from about 30° C. to about 95° C., for a time of from about 1 minute to about 10 hours, in embodiments from about 5 minutes to about 5 hours, to form a crosslinked polyester resin or polyester gel suitable for use as a shell.

[0117] If used, the crosslinker may be present in an amount of from about 0.001% to about 5% by weight of the resin, in embodiments from about 0.01% to about 1% by weight of the resin. The amount of CCA can be reduced in the presence of a crosslinker or initiator. Combine

[0118] Following aggregation to the desired particle size and optional application of a shell, the particles may then be coalesced into the desired final shape, which coalescence may be achieved by heating the mixture, for example, to a temperature of from about 45° C. to about 100° C., in embodiments from about 55° C. to about 99° C. (which may be at or above the glass transition temperature of the resin utilized to form the toner particles), and / or reducing the agitation, for example, to from about 100 rpm to about 400 rpm, in embodiments from about 200 rpm to about 300 rpm. The fused particles may be measured for shape factor or circularity, such as with a SYSMEX FPIA 2100 analyzer, until the desired shape is achieved.

[0119] Coalescence may be achieved over a period of from about 0.01 to about 9 hours, in embodiments from about 0.1 to about 4 hours. Subsequent processing

[0120] In some embodiments, after aggregation and / or coalescence, the pH of the mixture can be lowered to from about 3.5 to about 6, in embodiments from about 3.7 to about 5.5, for example, with an acid, to further coalesce the toner aggregates. Suitable acids include, for example, nitric acid, sulfuric acid, hydrochloric acid, citric acid, and / or acetic acid. The amount of acid added can be from about 0.1 to about 30 weight percent of the mixture, in embodiments from about 1 to about 20 weight percent of the mixture.

[0121] The mixture may be cooled, washed, and dried. Cooling may be at a temperature of about 20°C to about 40°C, in embodiments about 22°C to about 30°C, for about 1 hour to about 8 hours, in embodiments about 1.5 hours to about 5 hours.

[0122] In embodiments, cooling the coalesced toner slurry may include quenching, for example, by adding a cooling medium such as ice, dry ice, or the like, and rapidly cooling to a temperature of from about 20° C. to about 40° C., in embodiments from about 22° C. to about 30° C. Rapid cooling may be feasible for small amounts of toner, for example, less than about 2 liters, in embodiments from about 0.1 liters to about 1.5 liters. In larger scale processes, for example, greater than about 10 liters in size, rapid cooling of the toner mixture may not be feasible or practical, either by introducing a cooling medium into the toner mixture or by using jacketed reactor cooling.

[0123] The toner slurry may then be washed. Washing may be carried out at a pH of from about 7 to about 12, in embodiments from about 9 to about 11. Washing may be at a temperature of from about 30° C. to about 70° C., in embodiments from about 40° C. to about 67° C. Washing may include filtering and reslurrying the filter cake containing the toner particles in deionized water. The filter cake may be washed one or more times with deionized water, or the pH of the slurry may be adjusted with an acid to a pH of about 4 and washed with one deionized water wash, optionally followed by one or more deionized water washes.

[0124] Drying may be carried out by any method within the purview of those skilled in the art. Any suitable method for drying the toner particles may be used, including freeze drying, spray drying, and flash air drying, such as an Aljet dryer. Drying may be continued until the moisture level of the particles falls below a set target of about 1% by weight, in embodiments less than about 0.7% by weight. additives

[0125] In some embodiments, the toner particles may contain the polymeric toner additive particles of the present disclosure, as well as other optional additives, as desired or required. For example, the toner may include a positive or negative charge control agent in an amount of, for example, from about 0.1 to about 10% by weight of the toner, in embodiments from about 1 to about 3% by weight of the toner. Examples of suitable charge control agents include quaternary ammonium compounds, including alkylpyridinium halides; disulfates; alkylpyridinium compounds, including those disclosed in U.S. Pat. No. 4,298,672, incorporated herein by reference in its entirety; and organic sulfate and sulfonate compositions, including those disclosed in U.S. Pat. No. 4,338,390, incorporated herein by reference in its entirety.

[0126] The toner particles may also be blended with external additive particles after formation, including flow aid additives, which may be present on the surface of the toner particles. Examples of these additives include metal oxides such as titanium oxide, silicon oxide, aluminum oxide, cerium oxide, tin oxide, mixtures thereof, colloidal and amorphous silicas such as AEROSIL®, metal salts including zinc stearate, calcium stearate, and fatty acid metal salts, or long chain alcohols such as UNILIN 700, and mixtures thereof.

[0127] In general, silica may be applied to the toner surface for toner flow, triboelectric charge enhancement, admix control, improved development and transfer stability, and higher toner blocking temperature. TiO2 may be applied for improved relative humidity (RH) stability, triboelectric charge control, and improved development and transfer stability. Zinc stearate, calcium stearate, and / or magnesium stearate may optionally be used as an external additive to provide lubrication properties, developer conductivity, and triboelectric charge enhancement, thereby enabling higher toner charge and charge stability by increasing the number of contacts between the toner and carrier particles. In some embodiments, commercially available zinc stearate known as Zinc Stearate L, available from Ferro Corporation, may be used. External surface additives may be used with or without a coating.

[0128] Each of these external additives may be present in an amount of from about 0% to about 3% by weight of the toner, in embodiments from about 0.25% to about 2.5% by weight of the toner, although the additive amounts can be outside these ranges. In embodiments, the toner may include, for example, from about 0% to about 3% by weight of titania, from about 0% to about 3% by weight of silica, and from about 0% to about 3% by weight of zinc stearate.

[0129] In embodiments, in addition to the polymeric toner additive particles of the present disclosure, the toner particles may also comprise silica in an amount of from about 0.1% to about 5% by weight of the toner particles, in embodiments from about 0.2% to about 2% by weight of the toner particles, and titania in an amount of from about 0% to about 3% by weight of the toner particles, in embodiments from about 0.1% to about 1% by weight of the toner particles. Developer

[0130] The toner particles thus formed may be formulated into a developer composition. The toner particles may be mixed with carrier particles to form a two-component developer composition. The toner concentration in the developer may be from about 1% to about 25% by weight of the total weight of the developer, and in embodiments, from about 2% to about 15% by weight of the total weight of the developer. Career

[0131] Examples of carrier particles that can be used to mix with the toner include particles that can triboelectrically obtain a charge of opposite polarity to that of the toner particles. Illustrative examples of suitable carrier particles include granular zircon, granular silicon, glass, steel, nickel, ferrite, iron ferrite, silicon dioxide, etc. Other carriers include those disclosed in U.S. Patent Nos. 3,847,604, 4,937,166, and 4,935,326.

[0132] In some embodiments, a suitable carrier may comprise, for example, a steel core having a diameter of from about 25 to about 100 μm, in embodiments from about 50 to about 75 μm, coated with from about 0.5% to about 10% by weight, in embodiments from about 0.7% to about 5% by weight, of a conductive polymer blend including, for example, methyl acrylate and carbon black, using the processes described in U.S. Pat. Nos. 5,236,629 and 5,330,874.

[0133] The carrier particles can be mixed with the toner particles in various suitable combinations. The concentration can be from about 1% to about 20% by weight of the toner composition. However, different toner and carrier percentages can be used to obtain a developer composition with desired properties. Imaging

[0134] The toners may be utilized in electrostatographic or electrophotographic processes, such as those disclosed in U.S. Pat. No. 4,295,990, the disclosure of which is incorporated herein by reference in its entirety. In embodiments, any known type of development system may be used in the development device, including, for example, magnetic brush development, jumping single component development, hybrid scavengeless development (HSD), etc. These and similarly developed systems are within the purview of those skilled in the art.

[0135] Once the image is formed with toner / developer via a suitable development method, such as any one of the methods described above, the image can then be transferred to an image receiving medium, such as paper. In embodiments, the toner may be used for development in a development device that utilizes a fuser roll member.

[0136] The following examples are presented to illustrate embodiments of the present disclosure. These examples are intended for illustration only and are not intended to limit the scope of the present disclosure. Also, unless otherwise stated, parts and percentages are by weight. [Example]

[0137] Preparation of silica-based organic additive latex:

[0138] Example 1: Synthesis of organically loaded latex with 7.5% TS530 silica.

[0139] In a 2 L Buchi reactor equipped with two HE3 impellers, 3.75 g of SLS surfactant (30% solids) was added to 816 g of deionized water (DIW). The reactor was deoxygenated by passing a stream of nitrogen through it during the reaction. The reactor was heated to 77 °C and the rpm was set to 350. Separately, in a 1 L glass vessel equipped with two P4 impellers, a monomer emulsion was prepared by mixing together (at 450 rpm) 24.12 g of TS530 silica, 237 g of cyclohexyl methacrylate (CHMA), 80 g of DVB, 2.56 g of dimethyl-amino-ethyl methacrylate (DMAEMA), 9.18 g of sodium lauryl sulfate (SLS) surfactant (30% solids), and 416 g of DIW. 38.4 g of seeds were removed from the monomer emulsion and pumped into the 2 L reactor at 77 °C. An initiator solution prepared from 1.22 g of ammonium persulfate in 34.3 g of DIW was added over 20 minutes after the seed emulsion addition. The remaining monomer emulsion was fed to the reactor over 120 minutes. Once half of the monomer emulsion had been added, the rpm in the reactor was increased to 450 rpm. At the end of the monomer feed, the latex was subjected to a 1-hour post-treatment protocol at 77°C, followed by a 2-hour temperature increase to 87°C and a 1-hour hold at 87°C to reduce residual monomer at the end of the emulsion polymerization process. The rpm of the reactor was further increased to 530. The resulting latex had a particle size of 82 nm and contained 20% percent solids.

[0140] Example 2. Synthesis of an organic additive latex containing 3.5% Snowtex OS and 4% Aerosil A380 silica

[0141] In a 2-L Buchi reactor equipped with two HE3 impellers, 3.75 g of SLS surfactant (30% solids) and 53.2 g of Snowtex OS (21% solids) were added to 773 g of DIW. The reactor was deoxygenated by passing a stream of nitrogen through it during the reaction. The reactor was heated to 77°C and the rpm was set to 350. Separately, in a 1-L glass vessel equipped with two P4 impellers, a monomer emulsion was prepared by mixing together (at 450 rpm) 12.7 g of Aerosil A380, 237 g of CHMA, 80 g of DVB, 2.56 g of DMAEMA, 9.18 g of SLS surfactant (30% solids), and 416 g of DIW. 38.4 g of seeds were removed from the monomer emulsion and pumped into the 2-L reactor at 77°C. An initiator solution prepared from 1.22 g of ammonium persulfate in 34.3 g of DIW was added over 20 minutes after the seed emulsion addition. The remaining monomer emulsion was fed to the reactor over 120 minutes. Once half of the monomer emulsion had been added, the rpm in the reactor was increased to 450 rpm. At the end of the monomer feed, the latex was subjected to a 1-hour post-treatment protocol at 77°C, followed by a 2-hour temperature increase to 87°C and a 1-hour hold at 87°C to reduce residual monomer at the end of the emulsion polymerization process. Similarly, the reactor rpm was further increased to 530. The resulting latex had a particle size of 87 nm and contained 20% percent solids.

[0142] Comparative Example 3: Synthesis of silica-free organic polymer crosslinked latex.

[0143] A latex was prepared as in Example 1, but without the addition of inorganic particulates.

[0144] The SEM of Example 2 is shown in FIG.

[0145] Toner and Developer Preparation and Evaluation

[0146] Xerox 700 parent black toner was blended in a 10-L Henschel blender (manufactured by Reliance) with the additive formulations in Table 2. Each additive formulation also contained 0.95 pph of one of the organic additive latexes of Example 1 or Comparative Example 2.

[0147] Toner Example 3 was a toner blended with the organic additive latex of Example 1.

[0148] Comparative Toner Example 4 was a toner blended with the organic additive latex of Comparative Example 3. [Table 1]

[0149] For charge-per-toner evaluation, 30 g of Xerox 700 carrier was used with 1.50 g of blended toner in a 60 mL glass bottle. This resulted in a 5% toner concentration, or TC. A sample was conditioned for 3 days in the low humidity zone (J-zone) at 21.1°C and 10% RH, and another sample was conditioned for 3 days in the high humidity zone (A-zone) at approximately 28°C and 85% relative humidity. The developer was charged for 60 minutes in a Turbula mixer.

[0150] Toner charge was measured as the charge per mass ratio (Q / M). This was also determined by the total blow-off charge method, measuring the charge on the Faraday cage containing the developer after removing the toner by blow-off with an airflow. By weighing the cage before and after blow-off, the total charge collected in the cage was divided by the mass of toner removed by blow-off to obtain the Q / M ratio. Toner charge was also measured in the form of the charge-to-diameter ratio, q / d. q / d was measured using a charge spectrograph with a field of 100 V / cm and visually determined as the midpoint of the toner charge distribution. Charge was reported in millimeters of displacement from the zero line (mm displacement can be converted to femtocoulombs per micron (fC / μm) by multiplying by 0.092). Toner charge retention was measured as follows: Developer samples were prepared by weighing 1.5 g of additive toner into 30 g of carrier (5 pph) in a clean 60 mL glass bottle. The developer was conditioned in an A-zone environment at 28°C / 85% RH for 3 days to fully equilibrate. The developer was charged by agitating the sample in a Turbula mixer for 2 minutes. The charge per unit mass of the sample was measured using a Tribo Blow-Off. The sample was then returned to the A-zone chamber in the idle position. The charge per unit mass measurement was repeated again after 24 hours and 7 days. Charge retention is calculated from the 24 hour and 7 day charge as a percentage of the initial charge.

[0151] For flow evaluation, % cohesion at ambient laboratory temperature was obtained using a Hosokawa Micron Powder Tester. Two grams of blended toner was pre-weighed at ambient laboratory conditions and placed on the top sieve of three stacked mesh sieves in the Hosokawa flow tester in the following order: top 53 μm, middle 45 μm, bottom 38 μm. A 1 mm amplitude vibration was applied to the stack for 90 seconds. % cohesion at flow was calculated as % cohesion = (50 x A + 30 x B + 10 x C).

[0152] Toner blocking was determined for toners blended with surface additives by measuring toner cohesion at elevated temperatures above room temperature. Toner blocking measurements were completed as follows: 2 grams of the additive-blended toner was weighed into an open dish and conditioned in an environmental chamber at a specified elevated temperature and 50% relative humidity. After approximately 17 hours, the sample was removed and allowed to acclimate at ambient conditions for approximately 30 minutes. Each acclimatized sample was measured by sieving through two stacked pre-weighed mesh sieves (stacked as follows: 1000 μm on top, 106 μm on bottom). The sieves were vibrated using a Hosokawa flow tester at an amplitude of approximately 1 mm for approximately 90 seconds. After vibration was completed, the sieves were reweighed, and toner blocking was calculated from the total amount of toner remaining on both sieves as a percentage of the starting weight. Therefore, for a 2-gram toner sample, where A is the weight of the toner retained on the upper 1000 μm sieve and B is the weight of the toner retained on the lower 106 μm sieve, the toner blocking rate is calculated as %blocking = 50(A + B). %blocking was measured in this manner at temperatures varying by approximately 1°C around the expected blocking point. The blocking temperature was taken as the temperature at which %blocking increased to 20%. The results of all evaluations are shown in Table 2. [Table 2]

[0153] As shown in Table 2, the addition of negatively charged silica to the polymer crosslinked latex increased both the Q / D and Q / M charges in both environmental zones compared to Comparative Example 4. It also improved the % charge retention at 24 hours as well as 7 days, increased the blocking onset temperature, and reduced flow aggregation compared to Comparative Example 4.

[0154] To measure the print quality of the toner of Example 3 compared to the toner of Comparative Example 4, several further evaluations were performed. Both toners were printed under A-zone conditions on a Xerox 700 printer. Although both toners are black, this print test was performed in the cyan housing. In this printer, the black housing does not have a bias charging roller (BCR) for charging the photoreceptor, while the cyan housing does. Because the purpose of the test was to understand the cleaning of toner from the photoreceptor and BCR, the test was performed in the cyan housing. The test protocol is shown in Table 2. The first 2,000 prints for each toner were made at a high 20% toner print area coverage to switch from the toner that was in the printer. Then, an additional 1,000 prints at 20% print area coverage were made. The print was stopped, and at this checkpoint CP2, the prints were examined using a printed 100% solids toner patch measuring 80 mm x 80 mm. Visible spots were counted as listed in Table 3. The print run continued to CP3 at a low area coverage of 0.4%, which is very taxing for cleaning failure. Again, spots were counted and the run continued to CP4 as shown in the table. The toner of Example 3 showed only two spots total over four checkpoints, almost a complete absence of spots. Toner Comparative Example 4 showed much worse spots, with a total of 61 spots over the same checkpoints. [Table 3]

[0155] It will be understood that variations of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other different systems or applications. Various alternatives, modifications, variations, or improvements therein, presently not anticipated or foreseen, may be made by those skilled in the art, which are also encompassed by the following claims. Another aspect of the present invention may be as follows. [1] A toner composition, 1. A toner particle comprising: at least one resin; an optional colorant; an optional wax; and a polymeric toner additive on at least a portion of an outer surface of said toner particle, said polymeric toner additive comprising: 1. A toner composition comprising: crosslinked polymer particles on a surface of said toner particles, said crosslinked polymer particles comprising at least one hydrophobic monomer comprising a non-fluorinated or fluorinated monomer having a carbon to oxygen (C / O) ratio of 3 or greater; a second monomer comprising two or more vinyl groups present in said copolymer in an amount of from about 8% by weight to about 40% by weight; a metal oxide; and optionally a charge control agent monomer. [2] The toner composition according to [1] above, wherein the non-fluorinated monomer has a C / O ratio of 4 or more. [3] The toner composition according to [1], wherein the fluorinated monomer includes a fluorinated acrylate monomer or a fluorinated methacrylate monomer. [4] The toner composition according to [1], wherein the fluorinated monomer includes trifluoroethyl methacrylate. [5] The toner composition according to [1], wherein the charge control agent contains 0.1% by weight to 1.5% by weight of a nitrogen-containing group in the polymer resin. [6] The toner composition according to [5], wherein the charge control agent contains an acrylate monomer or a methacrylate monomer. [7] The toner composition according to [1], wherein the second monomer comprises divinylbenzene. [8] The toner composition according to [1], wherein the metal oxide is selected from the group consisting of silica, titania, and alumina. [9] The toner composition according to [1], wherein the toner particles comprise emulsion aggregation toner having a size of about 4 micrometers to about 10 micrometers.

[10] The toner composition according to [1], wherein the crosslinked polymer particles have a size ranging from 20 nanometers to 200 nanometers.

[11] The toner composition according to [1], wherein the crosslinked polymer particles have a crosslink density of 0.19 or more.

[12] A developer comprising a toner composition and a toner carrier, the toner composition comprising toner particles comprising at least one resin, an optional colorant, an optional wax, and a polymer toner additive on at least a portion of an outer surface of the toner particles, the crosslinked polymer particles being a developer comprising: crosslinked polymer particles on the surface of the toner particles, the crosslinked polymer particles comprising at least one hydrophobic monomer comprising a non-fluorinated or fluorinated monomer having a carbon-to-oxygen (C / O) ratio of 3 or greater; a second monomer comprising two or more vinyl groups present in the copolymer in an amount of about 8% by weight to about 40% by weight; a metal oxide; and optionally a charge control agent monomer.

[13] The developer according to

[12] , wherein the metal oxide is selected from the group consisting of silica, titania, and alumina.

[14] The developer according to

[12] , wherein the crosslinked polymer particles have a size ranging from 20 nanometers to 200 nanometers.

[15] The developer according to

[12] , wherein the metal oxide has a particle size of 7 nanometers to 50 nanometers.

[16] A toner additive, 1. A toner additive comprising: crosslinked polymer particles comprising at least one hydrophobic monomer comprising a non-fluorinated or fluorinated monomer having a carbon to oxygen (C / O) ratio of 3 or greater; a second monomer comprising two or more vinyl groups present in the copolymer in an amount of about 8% to about 40% by weight; a metal oxide; and optionally a charge control agent monomer.

[17] The toner additive according to

[16] , wherein the non-fluorinated hydrophobic monomer has a carbon to oxygen ratio of 3 or more.

[18] The toner additive according to

[16] , wherein the fluorinated hydrophobic monomer includes a fluorinated acrylate monomer or a fluorinated methacrylate monomer.

[19] The toner additive according to

[16] , wherein the metal oxide is selected from the group consisting of silica, titania, and alumina.

[20] The toner additive according to

[16] , wherein the crosslinked polymer particles have a size ranging from 20 nanometers to 200 nanometers.

Claims

1. 1. A toner composition comprising:

1. A toner particle comprising: at least one resin; an optional colorant; an optional wax; and a polymeric toner additive on at least a portion of an outer surface of said toner particle, said polymeric toner additive comprising: crosslinked polymer particles on the surface of the toner particles, the crosslinked polymer particles comprising at least one hydrophobic monomer comprising a non-fluorinated monomer or a fluorinated monomer having a carbon to oxygen (C / O) ratio of 3 or greater, a second monomer comprising two or more vinyl groups present in the copolymer in an amount of from about 8% to about 40% by weight, a metal oxide, and optionally a charge control agent monomer, the crosslinked polymer particles having a crosslink density of 0.19 or greater; The toner composition, wherein the second monomer containing two or more vinyl groups comprises a fluorinated crosslinker.

2. 10. The toner composition of claim 1, wherein said non-fluorinated monomer has a C / O ratio of 4 or greater.

3. The toner composition of claim 1 , wherein the fluorinated monomer comprises a fluorinated acrylate monomer or a fluorinated methacrylate monomer.

4. The toner composition of claim 1 , wherein the fluorinated monomer comprises trifluoroethyl methacrylate.

5. 2. The toner composition of claim 1, wherein said charge control agent comprises from 0.1% to 1.5% by weight of nitrogen-containing groups in said polymer resin.

6. The toner composition of claim 5 , wherein the charge control agent comprises an acrylate monomer or a methacrylate monomer.

7. 10. The toner composition of claim 1, wherein the second monomer comprises divinylbenzene.

8. 2. The toner composition of claim 1, wherein said metal oxide is selected from the group consisting of silica, titania, and alumina.

9. 10. The toner composition of claim 1, wherein the toner particles comprise emulsion aggregation toner having a size of from about 4 micrometers to about 10 micrometers.

10. 10. The toner composition of claim 1, wherein said crosslinked polymer particles comprise a size of from 20 nanometers to 200 nanometers.

11. 1. A developer comprising: a toner composition; and a toner carrier, said toner composition comprising toner particles comprising at least one resin, an optional colorant, an optional wax, and a polymeric toner additive on at least a portion of an outer surface of said toner particles, said polymeric toner additive comprising: crosslinked polymer particles on the surface of the toner particles, the crosslinked polymer particles comprising at least one hydrophobic monomer comprising a non-fluorinated monomer or a fluorinated monomer having a carbon to oxygen (C / O) ratio of 3 or greater, a second monomer comprising two or more vinyl groups present in the copolymer in an amount of from about 8% to about 40% by weight, a metal oxide, and optionally a charge control agent monomer, the crosslinked polymer particles having a crosslink density of 0.19 or greater; the second monomer comprising two or more vinyl groups comprises a fluorinated crosslinker; Developer.

12. 12. The developer of claim 11, wherein the metal oxide is selected from the group consisting of silica, titania, and alumina.

13. 12. The developer of claim 11, wherein the crosslinked polymer particles comprise a size between 20 nanometers and 200 nanometers.

14. 12. The developer of claim 11, wherein the metal oxide comprises a particle size of 7 nanometers to 50 nanometers.

15. 1. A toner additive comprising: crosslinked polymer particles comprising at least one hydrophobic monomer comprising a non-fluorinated or fluorinated monomer having a carbon to oxygen (C / O) ratio of 3 or greater, a second monomer comprising two or more vinyl groups present in the copolymer in an amount of about 8% to about 40% by weight, a metal oxide, and optionally a charge control agent monomer, the crosslinked polymer particles having a crosslink density of 0.19 or greater; the second monomer comprising two or more vinyl groups comprises a fluorinated crosslinker; Toner additives.

16. 16. The toner additive of claim 15, wherein said non-fluorinated hydrophobic monomer has a carbon to oxygen ratio of 4 or greater.

17. 16. The toner additive of claim 15, wherein said fluorinated hydrophobic monomer comprises a fluorinated acrylate monomer or a fluorinated methacrylate monomer.

18. 16. The toner additive of claim 15, wherein said metal oxide is selected from the group consisting of silica, titania, and alumina.

19. 16. The toner additive of claim 15, wherein said crosslinked polymer particles comprise a size of from 20 nanometers to 200 nanometers.

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