Toner composition

Abstract

Toner composition, comprehensive: a resin; Possibly a wax; a colorant; a needle-shaped surface additive, wherein the needle-shaped surface additive is needle-shaped titanium dioxide; wherein the needle-shaped surface additive is present in an amount of 0.25 wt% to 1.0 wt% of the toner composition; wherein the needle-shaped surface additive has a length of 0.25 to 8 micrometers; and wherein the needle-shaped surface additive has an aspect ratio of 4 to 25; optionally a spherical inorganic surface additive; and optionally a surface lubricant additive; and where toner particles of the toner composition have a roundness of 0.985 to 0.998.

Description

[0001] A toner composition is provided with a resin, optionally a wax, a colorant, a special needle-shaped surface additive, optionally a spherical inorganic surface additive and optionally a surface lubricant additive. Fig. Figure 1 illustrates the development hardware used in a non-magnetic, single-component development architecture; Fig. Figure 2 illustrates a toner particle with needle-shaped TiO2 according to an exemplary embodiment disclosed herein; Fig. Figure 3 is a graph showing the density changes versus the print number for a conventional toner composition and a toner composition according to embodiments herein; and Fig. Figure 4 is a graph representing the flow energy versus the amount of needle-shaped TiO2 in a toner composition according to embodiments herein.

[0002] US 2007 / 0231728A1 discloses a toner for an imaging device, comprising a chemically processed toner including a resin with a particle size of 1 to 25 µm, as well as additional particle-shaped additives containing silicon dioxide particles with a BET surface area of ​​more than 100 sq m. 2 / g and silicon dioxide particles with a BET surface area of ​​less than 100 sqm 2 / g as well as needle-shaped inorganic oxide particles.

[0003] JP 2003 - 280 249 A discloses an electrophotographic toner with a layer comprising fullerenes and / or carbon nanotubes on the toner particle surface, formed by implanting at least one type or more types of fullerenes and / or carbon nanotubes into the surface of the toner particle. The toner particle comprises at least a resin, a pigment, and a charge-controlling agent, and a surface coating layer formed by coating a layer of fullerenes and / or carbon nanotubes with an additive.

[0004] US 2011 / 0027713A1 relates to an electrophotographic toner comprising a binder resin and a light absorber, wherein the light absorber comprises metal nanorods and a surfactant covering the surface of the metal nanorods.

[0005] US 2008 / 0096116A1 relates to a toner comprising toner primary particles and inorganic fine particles, wherein the toner primary particles comprise a binder resin and a filler, the filler being contained in a filler layer near the surfaces of the toner primary particles, wherein the number-averaged particle diameter of the primary particles of the inorganic fine particles is 90 to 300 nm, and wherein the average circularity of the toner is 0.94 or greater.

[0006] JP S60 -135 956 A relates to a toner for a conventional developer, comprising hollow carbon fibers obtained using ultrafine particles of Fe, Ni or Co produced by the gas evaporation process.

[0007] The present disclosure provides a toner composition suitable, for example, for use in a single-component development system, wherein the toner composition possesses excellent loading, stability, and flow properties.

[0008] More precisely, the present invention provides a toner composition comprising: a resin; Possibly a wax; a colorant; a needle-shaped surface additive, wherein the needle-shaped surface additive is needle-shaped titanium dioxide; wherein the needle-shaped surface additive is present in an amount of 0.25 wt% to 1.0 wt% of the toner composition; wherein the needle-shaped surface additive has a length of 0.25 to 8 micrometers; and wherein the needle-shaped surface additive has an aspect ratio of 4 to 25; optionally a spherical inorganic surface additive; and optionally a surface lubricant additive; and where toner particles of the toner composition have a roundness of 0.985 to 0.998.

[0009] In embodiments described herein, needle-shaped surface additives are incorporated to reduce surface forces and tailor the flow properties of the toner particle without introducing changes to the particle shape. The surface additives can adhere to the toner particles and separate the toner particles from other surfaces. This separation can reduce the adhesion and cohesive forces on the toner and improve the transfer of toner from the photoconductor to intermediate and final receiving devices.

[0010] A needle-shaped surface additive, for example needle-shaped TiO2, can impart excellent stability and flow properties to the resulting toners. Furthermore, the toner compositions according to the embodiments described herein can reduce the occurrence of doctor blade fouling, printing defects, and low toner density compared to toners produced by conventional means.

[0011] The needle-like shape of the surface additive contained herein can help achieve improved toner removal capability from a photoconductor surface in a squeegee cleaning system. The needle-shaped surface additive can be used for improved stability against relative humidity (RH), improved tribocharging, and improved image development. Furthermore, it is believed that the needle-shaped surface additive can contribute to improved charging properties over a wide range of ambient temperatures and humidity levels for a toner particle that otherwise contains only spherical additives.

[0012] Fig.Figure 1 represents a printing system 2 according to one embodiment, such as a non-magnetic, single-component development system. Toner (not shown) is filled into a cartridge slot 4. A scoop (not shown) or gravity is used to load the toner onto a feed roller 6. The toner is then transferred to a development roller 8. As the development roller 8 rotates, the toner can be metered into the gap 12 between the loading blade 14 and the development roller 8. A photoconductor drum 13 can be arranged in contact with the development roller 8. The development roller 8 can be connected to a voltage source 16. A cleaning blade 18, which may include a urethane or silicone rubber blade mounted on a rigid holder 22, is attached to the cartridge housing 24.The physical properties and dimensions of the cleaning blade 18, for example, modulus, thickness, and length, can depend on the size of the photoconductor drum 13. The forces generated at the small gap 26 formed between the cleaning blade 18 and the photoconductor drum 13 ideally prevent residual toner from getting under the cleaning blade 18 and contaminating the power source 16. The toner should be able to be efficiently charged and flow into the gap 12 formed between the charging blade 14 and the developing roller 8, so that upon contact with the latent image, a sufficiently charged developed mass is present on the photoconductor drum 13.

[0013] Fig.Figure 2 shows a drawing of a toner particle 10 according to exemplary embodiments herein. This drawing is not intended to limit the scope of protection of the embodiments disclosed herein and serves only for clarity. The toner particle 10 according to embodiments herein must not require any changes to the mechanical design of the xerographic printing devices.

[0014] The toner particle 10 can include a resin / binder, colorant, gel, and wax.

[0015] As in Fig. As can be seen in Figure 2, a needle-shaped surface additive 20 in the toner particle, for example TiO2, can adhere to the outer surfaces of the toner particles 10 instead of being mixed into the mass of the toner particles 10.

[0016] The use of the needle-shaped surface additive 20 can reduce the moment of inertia of otherwise conventional toner particles and, consequently, the rolling effect of the toner particles under the contact gap formed between a photoconductor surface and a cleaning blade (not shown) of an SCD system. The presence of the needle-shaped surface additive 20 in the toner particle 10 can also reduce the probability that otherwise spherical toner particles will roll on the photoconductor surface (not shown) and / or under the cleaning blade (not shown) of an SCD system. Furthermore, the needle-shaped surface additive 20 can increase the cleaning performance of the cleaning blade (not shown) against a photoconductor surface. Needle-shaped surface additive

[0017] Needle-shaped surface additive(s) are used as reinforcing agents to improve the mechanical strength properties of the toner particles. The needle-shaped particles are primarily attached to the surface of the toner particles by electrostatic forces and, to a lesser extent, by mechanical impact. This allows the needle-shaped particles to be present on the outer surface of the toner particles in such a way that their longitudinal direction is parallel or oblique to the surface of the printing device, enabling the toner particles to slide on the squeegee.

[0018] The needle-shaped surface additive 20 is selected from needle-shaped titanium dioxide. The needle-shaped surface additive 20 can reduce the tendency of otherwise conventional toner particles to roll in an SCD system. The shape of the needle-shaped surface additive can be, for example, needle-like or irregular. Due to its needle-like shape, the additive can impart mechanical strength to the toner particle 10.

[0019] The needle-shaped surface additive is present in the toner composition at approximately 0.25 wt.% to approximately 1.0 wt.%, or from approximately 0.40 wt.% to approximately 0.60 wt.%, or approximately 0.5 wt.%.

[0020] The particles of the needle-shaped surface additive must not be very long, for example, from approximately 0.5 to approximately 6.0 micrometers, or from approximately 2.0 to approximately 4.0 micrometers, or from approximately 0.5 to 1.5 micrometers. However, the particles of the needle-shaped surface additive can have high aspect ratios (length / diameter), such as from approximately 5.0 to approximately 25.0 (l / d) or from approximately 8.0 to approximately 15.0 (l / d). Therefore, the needle-shaped surface additive can reduce the moment of inertia of the toner particles, preventing them from sliding / rolling under the cleaning blade (not shown) held against the photoconductor surface.

[0021] The needle-shaped TiO2 can be, for example, needle-shaped TiO2 distributed by Titan Kogyo or Sangyo Kaisha, which comes in various forms, as shown in the following micro-images.

[0022] Similar materials are supplied by Sangyo Kaisha. These materials have a rod-like shape but are larger than those offered by Titan Kogyo.

[0023] Basic characteristics of Sangyo Kaisha Latex resin FTL-100 FTL-200 FTL-300 Composition / Crystal TiO2 / Rutile TiO2 / Rutile TiO2 / Rutile Surface treatment --- --- --- Shape / Color Needle-shaped / White Needle-shaped / White Needle-shaped / White Particle length (µm) 1,68 2,86 5,15 Particle diameter (µm) 0,13 0,21 0,27 Relative density 4,2 4,2 4,2 Specific surface area (m²) 2 / G) 2) 10 ~ 15 7 ~ 10 5 ~ 7 Oil absorption (g / 100 g) 35 ~ 60 35 ~ 60 30 ~ 60 pH 6 ~ 8 6 ∼ 8 6 ~ 8

[0024] The toner compositions can, for example, include a latex resin in combination with a pigment.

[0025] Any monomer suitable for producing a latex for use in a toner particle can be used. Such latex particles can be produced by conventional methods. In some embodiments, the toner particle can be produced by emulsion / aggregation. Suitable monomers that can be used in forming a latex emulsion and consequently the resulting latex particles in the latex emulsion include, but are not limited to, styrenes, acrylates, polyesters, methacrylates, butadienes, isoprenes, acrylic acids, methacrylic acids, acrylonitriles, combinations thereof, and the like.

[0026] The resin can be produced by any process within the technical field of those skilled in the art. Illustrative examples of suitable toner resins include, for example, thermoplastic resins, such as vinyl resins in general or styrene resins in particular, and polyesters. Examples of suitable thermoplastic resins include styrene methacrylate; polyolefins; styrene acrylates, such as PSB-2700, obtained from Hercules-Sanyo Inc.; styrene butadiene; cross-linked styrene polymers; epoxides; polyurethanes; vinyl resins comprising homopolymers or copolymers of two or more vinyl monomers; and polymeric esterification products of a dicarboxylic acid and a diol comprising a diphenol.Other suitable vinyl monomers include styrene; p-chlororostyrene; unsaturated monoolefins, such as ethylene, propylene, butylene, isobutylene and the like; saturated monoolefins, such as vinyl acetate, vinyl propionate and vinyl butyrate; vinyl esters, such as esters of monocarboxylic acids. including methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate and butyl methacrylate; acrylonitrile; methacrylonitrile; acrylamide; mixtures thereof and the like. Cross-linked resins, including polymers, copolymers and homopolymers of styrene polymers, may also be selected.

[0027] In some embodiments, the resin of the latex may comprise at least one polymer. Examples of polymers include styrene acrylates, styrene butadienes, styrene methacrylates, and in particular poly(styrene alkyl acrylate), poly(styrene-1,3-diene), poly(styrene alkyl methacrylate), poly(styrene alkyl acrylate-acrylic acid), poly(styrene-1,3-diene acrylic acid), poly(styrene alkyl methacrylate-acrylic acid), poly(alkyl methacrylate-alkyl acrylate), poly(alkyl methacrylate-aryl acrylate), poly(aryl methacrylate-alkyl acrylate), poly(alkyl methacrylate-acrylic acid), poly(styrene alkyl acrylate-acrylonitrile acrylic acid), poly(styrene-1,3-diene acrylonitrile acrylic acid), poly(alkyl acrylate-acrylonitrile acrylic acid), poly(styrene-butadiene), poly(methyl styrene-butadiene), poly(methyl methacrylate-butadiene), and poly(ethyl methacrylate-butadiene). Poly(propyl methacrylate-butadiene), Poly(butyl methacrylate-butadiene), Poly(methyl acrylate-butadiene), Poly(ethyl acrylate-butadiene), Poly(propyl acrylate-butadiene), Poly(butyl acrylate-butadiene), Poly(styrene-isoprene)Poly(methylstyrene isoprene), Poly(methyl methacrylate isoprene), Poly(ethyl methacrylate isoprene), Poly(propyl methacrylate isoprene), Poly(butyl methacrylate isoprene), Poly(methyl acrylate isoprene), Poly(ethyl acrylate isoprene), Poly(propyl acrylate isoprene), Poly(butyl acrylate isoprene), Poly(styrene propyl acrylate), Poly(styrene butyl acrylate), Poly(styrene butadiene acrylic acid), Poly(styrene butadiene methacrylic acid), Poly(styrene butadiene acrylonitrile acrylic acid), Poly(styrene butyl acrylate acrylic acid), Poly(styrene butyl acrylate methacrylic acid), Poly(styrene butyl acrylate acrylononitrile), Poly(styrene-butyl acrylate-acrylonitrile-acrylic acid), poly(styrene-butadiene), poly(styrene isoprene), Poly(styrene-butyl methacrylate), poly(styrene-butyl acrylate-acrylic acid), poly(styrene-butyl methacrylate-acrylic acid), poly(butyl methacrylate-butyl acrylate), poly(butyl methacrylate-acrylic acid), poly(acrylonitrile-butyl acrylate-acrylic acid) and combinations thereof.

[0028] The polymer can be a block, statistical, or alternating copolymer. In some embodiments, a poly(styrene-butyl acrylate) can be used as the latex. The glass transition temperature of this latex can be approximately 35 °C to approximately 75 °C, and in other embodiments, approximately 40 °C to approximately 70 °C.

[0029] In other embodiments, the polymer used to form the latex can be a polyester resin. The polyesters can be amorphous, crystalline, or both.In embodiments, an unsaturated polyester resin can, for example, be an unsaturated polyester resin which, without being limited thereto, is poly(propoxylated bisphenol-co-fumarate), poly(ethoxylated bisphenol-co-fumarate), poly(butyloxylated bisphenol-co-fumarate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol-co-fumarate), poly(1,2-propylene fumarate), poly(propoxylated bisphenol-co-maleate), poly(ethoxylated bisphenol-co-maleate), poly(butyloxylated bisphenol-co-maleate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol-co-maleate), poly(1,2-propylene maleate), poly(propoxylated bisphenol-co-itaconate), poly(ethoxylated bisphenol-co-itaconate), poly(butyloxylated bisphenol-co-itaconate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol-co-itaconate), poly(1,2-propylene itaconate) and combinations thereof.

[0030] An example of a linear propoxylated bisphenol-A fumarate resin that can be used as a latex resin is available under the trade name SPARII from Resana S / A Industrias Quimicas, Sao Paulo, Brazil. Other propoxylated bisphenol-A fumarate resins that can be used and are commercially available include GTUF and FPESL-2 from Kao Corporation, Japan, EM181635 from Reichhold, Research Triangle Park, NC, and the like. surfactants

[0031] In some embodiments, the latex resin can be prepared in an aqueous phase comprising a surfactant or co-surfactant. Surfactants that can be used with the resin to form a latex dispersion can be ionic or nonionic surfactants in an amount of about 0.01 to about 15 percent by weight of the solids, and in embodiments, about 0.1 to about 10 percent by weight of the solids.

[0032] Anionic surfactants that may be used include sulfates and sulfonates, sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate, sodium dodecylnaphthalene sulfate, dialkylbenzene alkyl sulfates and sulfonates, acids such as abietic acid (available from Aldrich), NEOGEN R™, NEOGEN SC™ (available from Daiichi Kogyo Seiyaku), combinations thereof, and the like. Other suitable anionic surfactants include, in embodiments, DOWFAX™ 2A1, an alkyl diphenyl oxide disulfonate from the Dow Chemical Company, and / or TAYCA POWER BN2060 from Tayca Corporation (Japan), which are branched sodium dodecylbenzenesulfonates. In embodiments, combinations of these surfactants and any of the previously mentioned anionic surfactants may be used.

[0033] Examples of cationic surfactants include, but are not limited to, alkylbenzyldimethylammonium chloride, dialkylbenzenealkylammonium chloride, lauryltrimethylammonium chloride, alkylbenzylmethylammonium chloride, alkylbenzyldimethylammonium bromide, benzalkonium chloride, C12-, C15-, and C17-trimethylammonium bromides, combinations thereof, and the like. Other cationic surfactants include cetylpyridinium bromide, halide salts of quaternized polyoxyethylalkylamines, dodecylbenzyltriethylammonium chloride, MIRAPOL and ALKAQUAT, available from Alkaril Chemical Company, SANISOL (benzalkonium chloride), available from Kao Chemicals, combinations thereof, and the like. In embodiments, a suitable cationic surfactant comprises SANISOL B-50, available from Kao Corp., which is essentially a benzyldimethylalkonium chloride.

[0034] Examples of nonionic surfactants include, but are not limited to, alcohols, acids and ethers, for example polyvinyl alcohol, polyacrylic acid, methalose, methylcellulose, ethylcellulose, propylcellulose, hydroxyethylcellulose, carboxymethylcellulose, polyoxyethylene encetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonyl phenyl ether, dialkylphenoxypoly(ethyleneoxy)ethanol, combinations thereof and the like. In various embodiments, commercially available surfactants from Rhone-Poulenc, 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™, may be used. The selection of specific surfactants or combinations thereof, as well as their respective quantities, falls within the technical domain of those skilled in the art. initiators

[0035] In various embodiments, initiators can be added to form the latex. Examples of suitable initiators include water-soluble initiators, such as ammonium persulfate, sodium persulfate, and potassium persulfate, and organically soluble initiators, including organic peroxides and azo compounds, including vazo peroxides, such as VAZO 64™, 2-methyl 2-2'-azobispropanitrile, VAZO 88™, 2-2'-azobisisobutyramide dehydrate, and combinations thereof. Other water-soluble initiators that can be used include azoamidine compounds, for example, 2,2'-azobis(2-methyl-N-phenylpropionamidine) dihydrochloride, 2,2'-azobis[N-(4-chlorophenyl)-2-methylpropionamidine] dihydrochloride, 2,2'-azobis[N-(4-hydroxyphenyl)-2-methylpropionamidine] dihydrochloride, 2,2'-azobis[N-(4-aminophenyl)-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-hydroxyethyl)2-methylpropionamidine]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, combinations thereof and the like.

[0036] Initiators can be added in suitable quantities, such as from about 0.1 to about 8 percent by weight and in some embodiments from about 0.2 to about 5 percent by weight of the monomer. Chain transmission equipment

[0037] In various embodiments, chain transfer agents can also be used in the formation of the latex. Suitable chain transfer agents include dodecanethiol, octanthiol, carbon tetrachloride, combinations thereof, and the like, in amounts of about 0.1 to about 10% by weight, and in other embodiments, about 0.2 to about 5% by weight of monomers, in order to control the properties with respect to the relative molecular mass of the polymer when emulsion polymerization is carried out according to the present disclosure. Stabilizers

[0038] In exemplary embodiments, it may be advantageous to include a stabilizer during the formation of the latex particles. Suitable stabilizers may comprise monomers with carboxylic acid functionality.

[0039] In certain embodiments, the stabilizer with carboxylic acid functionality may also comprise a small amount of metal ions, such as sodium, potassium, and / or calcium, to improve emulsion polymerization results. The metal ions may be present in amounts ranging from approximately 0.001 to approximately 10% by weight of the stabilizer with carboxylic acid functionality, and in certain embodiments, from approximately 0.5% to approximately 5% by weight. If present, the stabilizer may be added in amounts ranging from approximately 0.01% to approximately 5% by weight of the toner, and in other embodiments, from approximately 0.05% to approximately 2% by weight of the toner.

[0040] Additional stabilizers that can be used in toner composition processes include bases such as metal hydroxides, including sodium hydroxide, potassium hydroxide, ammonium hydroxide, and optionally combinations thereof. Sodium carbonate, sodium bicarbonate, calcium carbonate, potassium carbonate, ammonium carbonate, combinations thereof, and the like can also be used as stabilizers. In embodiments, a stabilizer may comprise a composition containing sodium silicate dissolved in sodium hydroxide. pH adjuster

[0041] In some embodiments, a pH adjuster may be added to control the rate of the emulsion / aggregation process. The pH adjuster used in the processes of this disclosure may be any acid or base that does not adversely affect the products being manufactured. Suitable bases may include metal hydroxides, such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, and optionally combinations thereof. Suitable acids include nitric acid, sulfuric acid, hydrochloric acid, acetic acid, and optionally combinations thereof. colorant

[0042] Colorants that can be used in the formation of toner particles according to the present disclosure include pigments, dyes, mixtures of pigments and dyes, mixtures of pigments, mixtures of dyes, and the like. The colorant may be, for example, carbon black, cyan, yellow, magenta, red, orange, brown, green, blue, violet, and / or combinations thereof.

[0043] In one embodiment, the colorant can be a pigment. The pigment can be, for example, carbon black, phthalocyanines, quinacridones, or RHODAMINE B™ red, green, orange, brown, violet, yellow, fluorescent colorants, and the like. Examples of colorants include carbon black, such as REGAL 330® Magnetite; Mobay Magnetite, including MO8029™, MO8060™; Columbian Magnetite; MAPICO BLACKS™ and surface-treated magnetites; Pfizer Magnetite, including CB4799™, CB5300™, CB5600™, MCX6369™; Bayer Magnetite, including BAYFERROX 8600™, 8610™; Northern Pigment Magnetite, including NP-604™, NP-608™; Magnox Magnetite, including TMB-100™ or TMB-104™, HELIOGEN BLUE L6900™, D6840™, D7080™, D7020™, PYLAM OIL BLUE™, PYLAM OIL YELLOW™, PIGMENT BLUE 1™, available from Paul Uhlich and Company, Inc.; PIGMENT VIOLET 1™, PIGMENT RED 48™, LEMON CHROME YELLOW DCC 1026™, EDTOLUIDINE RED™ and BON RED C™, available from Dominion Color Corporation, Ltd., Toronto, Ontario; NOVAPERM YELLOW FGL™; HOSTAPERM PINK E™ from Hoechst; and CINQUASIA MAGENTA™, available from E.I. DuPont de Nemours and Company. Other colorants include 2,9-dimethyl-substituted quinacridone and anthraquinone dyes, identified in the Color Index as CI 60710, CI Dispersed Red 15; diazo dyes, identified in the Color Index as CI 26050, CI Solvent Red 19; copper tetra(octadecylsulfonamido)phthalocyanine; and x-copper phthalocyanine pigment, listed in the Color Index as CI 74160.Pigment Blue, Anthrathrene Blue, identified in the Color Index as CI 69810, Special Blue X-2137, Diarylide Yellow 3,3-Dichlorobenzideneacetoacetanilide, a monoazo pigment, identified in the Color Index as CI 12700, CI Solvent Yellow 16, a nitrophenylaminesulfonamide, identified in the Color Index as Foron Yellow SE / GLN, CI Dispersed Yellow 33, 2,5-Dimethoxy-4-sulfonamidephenylazo-4'-chloro-2,5-dimethoxyacetoacetanilide, Yellow 180, and Permanent Yellow FGL. Organic soluble dyes of high purity for color range purposes that may be used include Neopen Yellow 075, Neopen Yellow 159, Neopen Orange 252, Neopen Red 336, Neopen Red 335, Neopen Red 366, Neopen Blue 808, Neopen Black X53, Neopen Black X55, combinations of any of the above, and the like.The dyes can be used in various suitable amounts, such as from about 0.5 to about 20 percent by weight of the toner, and in some embodiments from about 5 to about 18 percent by weight of the toner.

[0044] In various embodiments, exemplary colorants may include Pigment Blue 15:3 with a Color Index Constitution Number (CODE) of 74160, Magenta Pigment Red 81:3 with a CODE of 45160:3, Yellow 17 with a CODE of 21105, and known dyes such as food colorings, yellow, green, red, magenta dyes, and the like. In other embodiments, a magenta pigment, Pigment Red 122 (2,9-dimethylquinacridone), Pigment Red 185, Pigment Red 192, Pigment Red 202, Pigment Red 206, Pigment Red 235, Pigment Red 269, combinations thereof, and the like may be used as the colorant.

[0045] The colorant can be present in the toner particle of the disclosure in an amount of about 1 to about 25 percent by weight of the toner, and in other embodiments in an amount of about 2 to about 15 percent by weight of the toner. The resulting latex, optionally in a dispersion, and the colorant dispersion can be stirred and heated to a temperature of about 35 °C to about 70 °C, and in various embodiments from about 40 °C to about 65 °C, leading to toner aggregates with a volume-average diameter of about 2 micrometers to about 10 micrometers, and in other embodiments with a volume-average diameter of about 5 micrometers to about 8 micrometers. Coagulant

[0046] In some embodiments, a coagulant may be added during or before the aggregation of the latex and the aqueous colorant dispersion. Depending on the processing conditions, the coagulant may be added over a period of approximately 1 minute to approximately 60 minutes, and in some embodiments, from approximately 1.25 minutes to approximately 20 minutes. Examples of suitable coagulants include polyaluminum halides, such as polyaluminum chloride (PAC), or the corresponding bromide, fluoride, or iodide; polyaluminum silicates, such as polyaluminum sulfosilicate (PASS); and water-soluble metal salts, including aluminum chloride, aluminum nitrite, aluminum sulfate, potassium aluminum sulfate, calcium acetate, calcium chloride, calcium nitrite, calcium oxylate, calcium sulfate, magnesium acetate, magnesium nitrate, magnesium sulfate, zinc acetate, zinc nitrate, zinc sulfate, combinations thereof, and the like.A suitable coagulant is PAC, which is commercially available and can be prepared by controlled hydrolysis of aluminum chloride with sodium hydroxide. Generally, PAC can be prepared by adding two moles of a base to one mole of aluminum chloride. The species is soluble upon dissolution and storage under acidic conditions and stable when the pH is below approximately 5. The species in solution is thought to have the formula Al. 13 O4(OH) 24 (H2O) 12 containing approximately 7 positive electrical charges per unit.

[0047] In exemplary embodiments, suitable coagulants comprise a polymetallic salt, such as polyaluminum chloride (PAC), polyaluminum bromide, or polyaluminum sulfosilicate. The polymetallic salt may be in a solution of nitric acid or other dilute acid solutions, such as sulfuric acid, hydrochloric acid, citric acid, or acetic acid. The coagulant may be added in amounts of approximately 0.01 to approximately 5 percent by weight of the toner, and in other embodiments, in amounts of approximately 0.1 to approximately 3 percent by weight of the toner. wax

[0048] Wax dispersions can be added during the formation of a latex or toner particle in an emulsion / aggregation synthesis. Suitable waxes include, for example, submicrometer-sized wax particles with a volume-mean diameter on the order of about 50 to about 1000 nanometers, and in some embodiments, about 100 to about 500 nanometers, suspended in an aqueous phase of water and an ionic surfactant, a non-ionic surfactant, or a combination thereof. Suitable surfactants include those described above. The ionic or non-ionic surfactant may be present in an amount of about 0.1 to about 20% by weight of the wax, and in other embodiments, about 0.5 to about 15% by weight.

[0049] The wax dispersion according to embodiments of the present disclosure may comprise, for example, natural vegetable wax, natural animal wax, mineral wax, and / or synthetic wax. Examples of natural vegetable waxes include, for example, carnauba wax, candelilla wax, Japan wax, and myrica wax. Examples of natural animal waxes include, for example, beeswax, Punic wax, lac wax, shellac wax, and spermaceti wax. Mineral waxes include, for example, paraffin wax, microcrystalline wax, montan wax, mountain wax, ceresin wax, petrolatum wax, and petroleum wax. Synthetic waxes of the present disclosure include, for example, Fischer-Tropsch wax, acrylate wax, solid acid amide wax, silicone wax, polytetrafluoroethylene wax, polyethylene wax, polypropylene wax, and combinations thereof.

[0050] Examples of polypropylene and polyethylene waxes include those commercially available from Allied Chemical and Baker Petrolite Corporation; wax emulsions available from Michaelman Inc. and Daniels Products Company; EPOLENE N-15, commercially available from Eastman Chemical Products, Inc.; VISCOL 550-P, a low weight-average relative molecular mass polypropylene available from Sanyo Kasei KK; and similar materials. In some embodiments, the commercially available polyethylene waxes have a relative molecular mass (Mw) of about 100 to about 5000, and in other embodiments, of about 250 to about 2500, while the commercially available polypropylene waxes have a relative molecular mass of about 200 to about 10,000, and in some embodiments, of about 400 to about 5000.

[0051] In some embodiments, the waxes may be functionalized. Examples of groups added to functionalize waxes include amines, amides, imides, esters, quaternary amines, and / or carboxylic acids. In some embodiments, the functionalized waxes may be acrylic polymer emulsions, for example, JONCRYL 74, 89, 130, 537, and 538, all available from Johnson Diversey, Inc.; or chlorinated polypropylenes and polyethylenes, commercially available from Allied Chemical, Baker Petrolite Corporation, and Johnson Diversey, Inc. The wax may be present in an amount of about 0.1 to about 30 percent by weight, and in some embodiments, about 2 to about 20 percent by weight of the toner. Aggregate formers

[0052] Any aggregate former capable of complex formation could be used in the formation of toner particles according to the present disclosure. Both alkaline earth metal and transition metal salts can be used as aggregate formers. In embodiments, alkali(II) salts may be selected for aggregating latex resin colloids with a colorant to enable the formation of a toner composition. Such salts include, for example, beryllium chloride, beryllium bromide, beryllium iodide, beryllium acetate, beryllium sulfate, magnesium chloride, magnesium bromide, magnesium iodide, magnesium acetate, magnesium sulfate, calcium chloride, calcium bromide, calcium iodide, calcium acetate, calcium sulfate, strontium chloride, strontium bromide, strontium iodide, strontium acetate, strontium sulfate, barium chloride, barium bromide, barium iodide, and optionally combinations thereof.Examples of transition metal salts or anions that can be used as aggregate formers include acetates of vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, iron, ruthenium, cobalt, nickel, copper, zinc, cadmium, or silver; acetoacetates of vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, iron, ruthenium, cobalt, nickel, copper, zinc, cadmium, or silver; sulfates of vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, iron, ruthenium, cobalt, nickel, copper, zinc, cadmium, or silver; and aluminum salts, such as aluminum acetate, aluminum halides, such as polyaluminum chloride, combinations thereof, and the like.

[0053] In various embodiments, the toner particles can also contain other optional additives, depending on requirements or preferences. For example, the toner particle can include additional positive or negative charge-controlling agents, for instance, in an amount of approximately 0.1 to approximately 10 percent by weight of the toner particle, and in some embodiments, approximately 1 to approximately 3 percent by weight of the toner particle. Examples of suitable charge-controlling agents include quaternary ammonium compounds, including alkylpyridinium halides; bisulfates; alkylpyridinium compounds, organic sulfate and sulfonate compositions; cetylpyridinium tetrafluoroborates; distearyldimethylammonium methyl sulfate; aluminum salts, including, for example, BONTRON® E-84 or BONTRON® E-88 (Hodogaya Chemical), combinations thereof, and the like. BONTRON® E-84 is a zinc complex of 3,5-di-tert-butylsalicylic acid in powder form.BONTRON® E-88 is a mixture of hydroxyaluminium bis[2-hydroxy-3,5-di-tert-butylbenzoate] and 3,5-di-tert-butyl salicylic acid.

[0054] They can also be mixed with external additive particles of toner particles, including flow-enhancing additives, the additives being present on the surface of the toner particles. Examples of these additives include metal oxides, such as titanium oxide, titanium dioxide, silicon dioxide, tin oxide, mixtures thereof, and the like; colloidal and amorphous silicas, such as AEROSIL®; metal salts and metal salts of fatty acids, including zinc stearate, strontium stearate, calcium stearate, aluminum oxides, cerium oxides, and mixtures thereof. Each of these external additives may be present in an amount of approximately 0.1% to approximately 5% by weight of the toner, and in some embodiments, from approximately 0.25% to approximately 3% by weight of the toner particle. Example

[0055] The following example illustrates an exemplary embodiment of the present disclosure. This example serves only to illustrate one of several methods for producing the toner particle and is not intended to limit the scope of protection of the present disclosure. Furthermore, all parts and percentages are based on weight unless otherwise stated. Production of toner particles*

[0056] The EA toner particles were produced in a reactor with a capacity of 75.71 liters (20 gallons). The reactor was equipped with two stainless steel impeller stirrers mounted on a vertical shaft, a condenser, a nitrogen inlet, a thermometer, a 12R thermocouple adapter, a heater, and a cooling jacket. The reactor was filled with 29.7 kg of deionized water, 15.7 kg of a styrene-butyl acrylate resin in a latex emulsion with a solids content of approximately 41.5%, 0.71 kg of a cyanopigment dispersion with a solids content of approximately 17%, and approximately 3.47 kg of a carbon black pigment dispersion with a solids content of approximately 17%.

[0057] The contents of the reactor were mixed together before the addition of 2.96 kg of a paraffin wax dispersion with a solids content of approximately 31% and 1.76 kg of an acid solution containing an agglomerate former, such as polyaluminum chloride. The wax dispersion was added through a homogenization loop to ensure that large agglomerates were broken down into smaller particles. After the addition of the wax dispersion and agglomerate former solution to the reactor, all components were homogenized for six minutes or until the particle size in the dispersion was within a predetermined range.

[0058] After homogenizing the components in the reactor, the temperature of the mixture was increased to approximately 56 °C until the particle aggregate reached the target size. At this point, the pre-cladding or core formation was complete. Once the particles reached the target size, an additional 7.59 kg of a styrene-butyl acrylate resin in a latex emulsion was added to the reactor. The latex was mixed into the reactor until the particles reached their final target size, and sufficient time was allowed for all of the additional latex emulsion to be incorporated into the core particles. Once the target size was reached, the cladding step was complete.

[0059] Once the final particle size was reached, particle growth was stopped by adding 1.395 g of sodium hydroxide until the pH of the suspension reached a value of 4.5 to 4.9. Once the pH was confirmed, the target temperature of the batch was increased to 96 °C. When the suspension reached a temperature of 90 °C, its pH was adjusted by adding 190 g of nitric acid until the pH of the suspension reached a value of 3.8 to 4.2.

[0060] Once the batch reached 96 °C, the temperature of the suspension was held constant, and the particle roundness was monitored over time. When the roundness reached the target value of approximately 0.980 to 0.990, or approximately 0.985 to 0.990, or approximately 0.988, the temperature of the suspension was reduced to 53 °C at a rate of 0.6 °C / min. When the temperature of the suspension reached 57 °C, the pH was adjusted by adding 774 g of sodium hydroxide until the pH of the suspension reached a value of 7.5 to 7.9.

[0061] Once the suspension was prepared with particles of the predetermined size and roundness, the particles underwent a series of steps known as downstream processes. These processes include sieving the suspension to remove particles larger than the predetermined size required, which may have formed as a result of the high temperature in the reactor; washing the particles to remove surfactants or other ionic species that impart undesirable charging properties; and removing excess moisture by drying the particles. Production of toner compositions

[0062] The EA particles were mixed with surface additives in a vertical 10-liter high-speed mixer, such as those supplied by Henschel. The mixer was filled with 1.5 kg (3.3 lbs) of EA particles, followed by surface-treated pyrogenic silica at a concentration of approximately 1.4%. Once the EA particles and the surface-treated pyrogenic silica were mixed, the needle-shaped TiO₂ was added. The components in the mixer were mixed together for approximately 13.3 minutes. After this initial mixing cycle, a metal stearate additive at a concentration of 0.14% was added. All components in the mixer were mixed together for 3 minutes.

[0063] Table I presents the components of each of the exemplary toner compositions produced according to the preceding example, along with the quantity of each component. TABLE I Toner 1 Toner 2 Toner 3 Toner 4 Toner 5 EA particles (Ibs) 3,3 3,3 3,3 3,3 3,3 % 1,4 1,4 1,4 1,4 1,4 surface-treated Silica % Metal stearate 0,14 0,14 0,14 0,14 0,14 % needle-shaped TiO2 0 0,25 0,50 0,50 1,0

[0064] Toner 3 and Toner 4 have exactly the same composition. The difference lies in the fact that, in Toner 4, the needle-shaped TiO2 was added along with the metal stearate during the second mixing step. With the other toners containing needle-shaped TiO2, the additive was added during the first mixing step along with the surface-treated silica.

[0065] Fig. Figure 3 is a graph showing the density changes with respect to the print count for a conventional toner composition and a toner composition with needle-shaped TiO2 according to embodiments herein. The graph shows that when using a conventional toner composition with toner particles having a roundness of 0.975, the density of the toner composition decreases with increasing print count. The toner composition according to embodiments herein with toner particles having a roundness of 0.988 is more stable over time. Furthermore, Figure 3 shows Fig.3, that the toner particles of the embodiments herein have a density of at least 1.3 densitometer units.

[0066] Fig. Figure 4 presents a graph showing the energy required to make the toner flow versus the amount of needle-shaped TiO2 in a toner composition according to embodiments herein. As can be seen on the graph, the energy required to make the toner flow increases with increasing amount of needle-shaped TiO2. The increased energy required to initiate the mass flow of toner particles with an increased amount of needle-shaped titanium dioxide is indicative of reduced flowability and increased clumping between particles. This means that more force is required to break up a consolidated group of particles and to make the particles roll, which provides the cleaning improvement.

Claims

[1] Toner composition, comprising: a resin; Possibly a wax; a colorant; a needle-shaped surface additive, wherein the needle-shaped surface additive is needle-shaped titanium dioxide; wherein the needle-shaped surface additive is present in an amount of 0.25 wt% to 1.0 wt% of the toner composition; wherein the needle-shaped surface additive has a length of 0.25 to 8 micrometers; and wherein the needle-shaped surface additive has an aspect ratio of 4 to 25; optionally a spherical inorganic surface additive; and optionally a surface lubricant additive; and where toner particles of the toner composition have a roundness of 0.985 to 0.

998. [2] Toner composition according to claim 1, wherein the needle-shaped surface additive is in an outer layer of the toner particles of the toner composition.

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