Toner Containing a Toner Additive Formulation

Abstract

The present invention describes a toner comprising: mother toner particles comprising at least one resin combined with an optional colorant, and an optional wax; and a surface additive formulation comprising at least one medium silica surface additive; at least one large silica surface additive; at least one positively charged surface additive, wherein the at least one positively charged surface additive is (a) a titanium dioxide surface additive; and wherein the mother toner particles further comprise small silica; or (b) a positively charged non-titanium dioxide metal oxide surface additive; and wherein the mother toner particles further optionally comprise small silica; and wherein the total surface area coverage of all the combined surface additives is 100% to 140% of the surface area of the mother toner particles.

Description

[0001] Related patent applications

[0002] The co-pending, co-assigned U.S. Patent Application No. 16 / 800,236 (Attorney Docket No. 20190392US01, entitled "Titania-Free Toner Additive Formulation With Cross-Linked Organic Polymeric Additive"), filed concurrently with the present invention, describes a toner comprising: mother toner particles comprising at least one resin combined with an optional colorant and an optional wax; and a surface additive formulation comprising at least one medium silica surface additive; at least one large cross-linked organic polymer additive; at least one positively charged surface additive, wherein the at least one positively charged surface additive is (a) a titanium dioxide surface additive; and wherein the mother toner particles further comprise small silica; or (b) a positively charged non-titanium dioxide metal oxide surface additive; and wherein the mother toner particles further optionally comprise small silica; and wherein the total surface area coverage of all of the combined surface additives is from 100% to 140% of the surface area of the mother toner particles. Background Art

[0003] The present disclosure relates to a toner, the toner comprising mother toner particles, the mother toner particles comprising at least one resin combined with an optional colorant, and an optional wax; and a surface additive formulation, the surface additive formulation comprising: at least one medium silica surface additive having a volume average primary particle size of 30 nanometers to 50 nanometers, the at least one medium silica being provided at a surface area coverage of 40% to 100% of the surface area of the mother toner particles; at least one large silica surface additive having a volume average primary particle size of 80 nanometers to 120 nanometers, the at least one large silica being provided at a surface area coverage of 5% to 29% of the surface area of the mother toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having an average primary particle size of 15 nanometers to 40 nanometers, the titanium dioxide being present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the mother toner particles; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 5% to 75% of the surface area of the mother toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 0% to 75% of the surface area of the mother toner particles; and wherein the total surface area coverage of all the combined surface additives is 100% to 140% of the surface area of the mother toner particles.

[0004] The present invention also discloses a toner method, which includes: contacting at least one resin, an optional wax, an optional colorant, and an optional aggregating agent; heating to form aggregated toner particles; optionally, adding a shell resin to the aggregated toner particles and heating to a further elevated temperature to coalesce the particles; adding a surface additive, which comprises: at least one medium silica surface additive having a volume average primary particle size of 30 nanometers to 50 nanometers, and the at least one medium silica is provided at a surface area coverage rate of 40% to 100% of the surface area of the parent toner particles; at least one large silica surface additive having a volume average primary particle size of 80 nanometers to 120 nanometers, and the at least one large silica is provided at a surface area coverage rate of 5% to 29% of the surface area of the parent toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having an average primary particle size of 15 nanometers to 40 nanometers, and based on 100 parts of the parent toner particles, titanium dioxide is present in an amount of less than or equal to 1 part per hundred parts; and wherein the parent toner particles further comprise small silica having a volume average primary particle size of 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage rate of 5% to 75% of the surface area of the parent toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage rate of 5% to 15% of the surface area of the parent toner particles; and wherein the parent toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage rate of 0% to 75% of the surface area of the parent toner particles; and wherein the total surface area coverage rate of all the combined surface additives is 100% to 140% of the surface area of the parent toner particles.

[0005] Electrophotographic printing utilizes toner particles that can be prepared by a variety of methods. One such method includes the emulsion aggregation (“EA”) method of forming toner particles, where surfactants are used to form a latex emulsion. See, for example, U.S. Patent No. 6,120,967, the disclosure of which is hereby incorporated by reference in its entirety as an example of such a method.

[0006] Combinations of amorphous polyesters and crystalline polyesters can be used in the EA process. The resin combination can provide a toner having high gloss and relatively low melting point characteristics (sometimes referred to as low melt, ultra-low melt, or ULM), which allows for more energy-efficient and faster printing. Other toner resins can also be selected for the toner, such as styrene or styrene acrylate copolymers. Such resins can include one or more resins selected from the group consisting of: styrene, acrylate, methacrylate, butadiene, isoprene, acrylic acid, methacrylic acid, acrylonitrile, their copolymers, and combinations thereof. The toner can also be a hybrid toner in which a combination of a polyester resin and other resins such as styrene, etc. is used in the toner particles.

[0007] The use of additives with EA toner particles can be important for achieving optimal toner performance (such as for providing improved charging characteristics, improved flowability, etc.). Poor fusing can cause problems with paper adhesion and printing performance. Poor toner flow cohesiveness can affect toner dispensing, which can create problems in gravity feed hoppers and result in missing on the paper. In addition, the use of additives with EA toner particles can also reduce bias charge roller (BCR) contamination.

[0008] U.S. Patent 8,663,886 (incorporated herein by reference in its entirety) describes in its specification abstract a polymeric additive for use with toner particles. The polymeric additive comprises a copolymer having: at least one monomer having a high carbon-to-oxygen ratio, a monomer having more than one vinyl group, and at least one amine-functionalized monomer.

[0009] U.S. Patent Application Serial No. 15 / 914,411, entitled “Toner Compositions And SurfacePolymer Additives” by Richard P.N.Veregin et al. (incorporated herein by reference in its entirety) describes in its specification abstract a polymeric composition for use with toner particles. The polymeric composition comprises a silicone-polyether copolymer and a polymeric additive, wherein the silicone-polyether copolymer comprises a polysiloxane unit and a polyether unit, and the polymeric additive comprises a copolymer having: at least one monomer having a high carbon-to-oxygen ratio, a monomer having more than one vinyl group, and at least one amine-functionalized monomer.

[0010] There has been a continuing need to improve the additives used in toners, including those for forming EA toners, especially low melt EA toners, to improve toner flowability, toner adhesion that results in poor toner flowability, or toner caking at high temperatures, toner charge, and to reduce BCR contamination. There has also been a continuing need to develop lower cost EA toners.

[0011] Due to certain regulatory requirements, compositions expected to contain toner with one percent or more titanium dioxide will ultimately require special labeling. Additionally, having titanium dioxide in the toner formulation is expected to have Blue Angel certification issues. Further, silica and titanium dioxide additives significantly increase the cost of the toner formulation. Accordingly, there is a need to reduce or eliminate titanium dioxide in the toner formulation.

[0012] Currently available toners and toner methods are suitable for their intended purposes. However, there is still a need for improved toners and toner methods. Additionally, there is still a need for improved emulsion aggregation toners and toner methods. Additionally, there is still a need for a toner composition that has performance characteristics as good as or better than existing compositions while meeting the need to reduce the amount of titanium dioxide. Additionally, there is still a need for a toner composition that can function as needed without the need for titanium dioxide additives.

[0013] In embodiments of the present disclosure, appropriate components and method aspects of each of the above U.S. patents and patent publications may be selected for the present disclosure. Additionally, throughout this application, various publications, patents, and published patent applications are cited by identification. The disclosures of the publications, patents, and published patent applications cited in this application are hereby incorporated by reference into the present disclosure to more fully describe the state of the art to which this invention pertains. SUMMARY OF THE INVENTION

[0014] The present invention describes a toner comprising mother toner particles, the mother toner particles comprising at least one resin combined with an optional colorant and an optional wax; and a surface additive formulation, the surface additive formulation comprising: at least one medium silica surface additive having a volume average primary particle size of 30 nanometers to 50 nanometers, the at least one medium silica being provided at a surface area coverage of 40% to 100% of the surface area of the mother toner particles; at least one large silica surface additive having a volume average primary particle size of 80 nanometers to 120 nanometers, the at least one large silica being provided at a surface area coverage of 5% to 29% of the surface area of the mother toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having an average primary particle size of 15 nanometers to 40 nanometers, the titanium dioxide being present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the mother toner particles; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 5% to 75% of the surface area of the mother toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 0% to 75% of the surface area of the mother toner particles; and wherein the total surface area coverage of all the combined surface additives is 100% to 140% of the surface area of the mother toner particles.

[0015] The present invention also describes a toner method, the method comprising: contacting at least one resin, an optional wax, an optional colorant, and an optional aggregating agent; heating to form aggregated toner particles; optionally, adding a shell resin to the aggregated toner particles and heating to a further elevated temperature to coalesce the particles; adding a surface additive, the surface additive comprising: at least one medium silica surface additive having a volume average primary particle size of from 30 nanometers to 50 nanometers, the at least one medium silica being provided at a surface area coverage of from 40% to 100% of the surface area of the parent toner particles; at least one large silica surface additive having a volume average primary particle size of from 80 nanometers to 120 nanometers, the at least one large silica being provided at a surface area coverage of from 5% to 29% of the surface area of the parent toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having an average primary particle size of from 15 nanometers to 40 nanometers, the titanium dioxide being present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the parent toner particles; and wherein the parent toner particles further comprise small silica having a volume average primary particle size of from 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of from 5% to 75% of the surface area of the parent toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of from 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of from 5% to 15% of the surface area of the parent toner particles; and wherein the parent toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of from 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of from 0% to 75% of the surface area of the parent toner particles; and wherein the total surface area coverage of all of the combined surface additives is from 100% to 140% of the surface area of the parent toner particles; and optionally, recovering the toner particles. Detailed Description

[0016] The present disclosure provides a toner that provides desired performance characteristics, the performance characteristics including one or a combination of one or more of sufficient, acceptable, or excellent flowability, charge, charge distribution, photoreceptor cleanability, developer flow characteristics, and storage performance after handling under high humidity conditions. The present invention provides a toner composition having a toner surface additive formulation to reduce or replace a titanium dioxide surface additive.

[0017] In an embodiment, a toner is provided that includes mother toner particles comprising at least one resin combined with an optional colorant and an optional wax; and a surface additive formulation comprising: at least one medium silica surface additive having a volume average primary particle size of 30 nanometers to 50 nanometers, the at least one medium silica provided at a surface area coverage of 40% to 100% of the surface area of the mother toner particles; at least one large silica surface additive having a volume average primary particle size of 80 nanometers to 120 nanometers, the at least one large silica provided at a surface area coverage of 5% to 29% of the surface area of the mother toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having an average primary particle size of 15 nanometers to 40 nanometers, the titanium dioxide present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the mother toner particles; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica present at a surface area coverage of 5% to 75% of the surface area of the mother toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica present at a surface area coverage of 0% to 75% of the surface area of the mother toner particles; and wherein the total surface area coverage of all of the combined surface additives is 100% to 140% of the surface area of the mother toner particles.

[0018] The toner surface additive formulation can be combined with a toner resin, optionally having a colorant, to form the toner of the present disclosure.

[0019] Any toner resin can be used to form the toner of the present disclosure. Such resins can in turn be made from any suitable monomer or monomers via any suitable polymerization method. In an embodiment, the resin can be prepared by a method other than emulsion polymerization. In a further embodiment, the resin can be prepared by condensation polymerization.

[0020] The toner may include one or more polyester resins. In an embodiment, the polyester resin may be amorphous, crystalline, or a combination of amorphous polyester and crystalline polyester. In other embodiments, the toner includes a styrene or styrene-acrylate resin. In other embodiments, the toner may include a hybrid toner containing two or more types of toner resins such as polyester and styrene-acrylate.

[0021] Amorphous resin

[0022] In an embodiment, the toner composition includes at least one amorphous polyester. In an embodiment, the toner composition includes at least one amorphous polyester and at least one crystalline polyester. In certain embodiments, at least one polyester includes a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester. In additional embodiments, at least one polyester in the toner includes a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester, and a crystalline polyester.

[0023] The amorphous resin may be an amorphous polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. Examples of the diacid or diester include vinyl diacids or vinyl diesters for preparing amorphous polyesters, and include dicarboxylic acids or diesters such as terephthalic acid, phthalic acid, isophthalic acid, fumaric acid, trimellitic acid, dimethyl fumarate, dimethyl itaconate, cis-1,4-diacetoxy-2-butene, diethyl fumarate, diethyl maleate, maleic acid, succinic acid, itaconic acid, succinic acid, succinic anhydride, dodecylsuccinic acid, dodecylsuccinic anhydride, glutaric acid, glutaric anhydride, adipic acid, pimelic acid, suberic acid, azelaic acid, dodecanedioic acid, dimethyl terephthalate, diethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, dimethyl phthalate, phthalic anhydride, diethyl phthalate, dimethyl succinate, dimethyl fumarate, dimethyl maleate, dimethyl glutarate, dimethyl adipate, dimethyl dodecylsuccinate, and combinations thereof. The organic diacid or diester may be present, for example, in an amount of about 40 mol% to about 60 mol% of the resin, about 42 mol% to about 52 mol% of the resin, or about 45 mol% to about 50 mol% of the resin.

[0024] Examples of diols useful for generating amorphous polyesters include 1,2 - propanediol, 1,3 - propanediol, 1,2 - butanediol, 1,3 - butanediol, 1,4 - butanediol, pentanediol, hexanediol, 2,2 - dimethylpropanediol, 2,2,3 - trimethylhexanediol, heptanediol, dodecanediol, bis(hydroxyethyl)-bisphenol A, bis(2 - hydroxypropyl)-bisphenol A, 1,4 - cyclohexanedimethanol, 1,3 - cyclohexanedimethanol, xylene dimethanol, cyclohexanediol, diethylene glycol, bis(2 - hydroxyethyl)oxide, dipropylene glycol, dibutene, and combinations thereof. The amount of the selected organic diol can vary. For example, the organic diol can be present in an amount of about 40 mol% to about 60 mol% of the resin, about 42 mol% to about 55 mol% of the resin, or about 45 mol% to about 53 mol% of the resin.

[0025] Examples of suitable amorphous resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutene, polyisobutyrate, ethylene - propylene copolymers, ethylene - vinyl acetate copolymers, polypropylene, etc., and mixtures thereof.

[0026] Unsaturated amorphous polyester resins can be used as the resin. Examples of such resins include those disclosed in U.S. Patent No. 6,063,827, the disclosure of which is hereby incorporated by reference in its entirety. Exemplary unsaturated amorphous polyester resins include, but are not limited to, poly(propoxylated bisphenol co - fumarate), poly(ethoxylated bisphenol co - fumarate), poly(butoxylated bisphenol co - fumarate), poly(co - propoxylated bisphenol co - ethoxylated bisphenol co - fumarate), poly(1,2 - propanediol fumarate), poly(propoxylated bisphenol co - maleate), poly(ethoxylated bisphenol co - maleate), poly(butoxylated bisphenol co - maleate), poly(co - propoxylated bisphenol co - ethoxylated bisphenol co - maleate), poly(1,2 - propanediol maleate), poly(propoxylated bisphenol co - itaconate), poly(ethoxylated bisphenol co - itaconate), poly(butoxylated bisphenol co - itaconate), poly(co - propoxylated bisphenol co - ethoxylated bisphenol co - itaconate), poly(1,2 - propanediol itaconate), and combinations thereof.

[0027] Suitable polyester resins can be amorphous polyesters, such as poly(propoxylated bisphenol A co - fumarate) resin. Examples of such resins and their preparation methods include those disclosed in U.S. Patent 6,063,827, the disclosure of which is hereby incorporated by reference in its entirety.

[0028] Suitable polyester resins include amorphous acidic polyester resins. The amorphous acidic polyester resins can be based on any combination of propoxylated bisphenol A, ethoxylated bisphenol A, terephthalic acid, fumaric acid, and dodecenyl succinic anhydride, such as poly(propoxylated bisphenol-co-terephthalate-fumarate-dodecenyl succinate). Another amorphous acidic polyester resin that can be used is poly(propoxylated-ethoxylated bisphenol-co-terephthalate-dodecenyl succinate-trimellitic anhydride).

[0029] Examples of linear propoxylated bisphenol A fumarate resins that can be used as resins can be obtained 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, and EM181635 from Reichhold, Research Triangle Park, N.C., etc.

[0030] The amorphous resin or combination of amorphous resins can be present, for example, in an amount of about 5 wt% to about 95 wt% of the toner, about 30 wt% to about 90 wt% of the toner, or about 35 wt% to about 85 wt% of the toner.

[0031] In an embodiment, based on the total weight of the toner composition, the toner composition contains an amount of amorphous polyester in the range of about 73 wt% to about 78 wt%. In certain embodiments, the toner composition contains a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester, and based on the total weight of the toner composition, the total amount of amorphous polyester containing both the first amorphous polyester and the second amorphous polyester is about 73 wt% to about 78 wt%.

[0032] The amorphous resin or combination of amorphous resins can have a glass transition temperature of about 30°C to about 80°C, about 35°C to about 70°C, or about 40°C to about 65°C. The glass transition temperature can be measured using differential scanning calorimetry (DSC). The amorphous resin can have an Mn, measured by GPC, of, for example, about 1,000 to about 50,000, about 2,000 to about 25,000, or about 1,000 to about 10,000, and an Mw, determined by GPC, of, for example, about 2,000 to about 100,000, about 5,000 to about 90,000, about 10,000 to about 90,000, about 10,000 to about 30,000, or about 70,000 to about 100,000.

[0033] In an embodiment, one, two, or more resins may be used. In the case of using two or more resins, the resins may have any suitable ratio (e.g., weight ratio) such as from about 1% (first resin) / 99% (second resin) to about 99% (first resin) / 1% (second resin), from about 10% (first resin) / 90% (second resin) to about 90% (first resin) / 10% (second resin). In the case where the resin comprises a combination of an amorphous resin and a crystalline resin, the resin may have, for example, a weight ratio of from about 1% (crystalline resin) / 99% (amorphous resin) to about 99% (crystalline resin) / 1% (amorphous resin) or from about 10% (crystalline resin) / 90% (amorphous resin) to about 90% (crystalline resin) / 10% (amorphous resin). In some embodiments, the weight ratio of the resin is about 80% to about 60% amorphous resin and about 20% to about 40% crystalline resin. In such embodiments, the amorphous resin may be a combination of amorphous resins, such as a combination of two amorphous resins.

[0034] Crystalline resin 。

[0035] In an embodiment, the toner herein comprises a crystalline polyester. The crystalline resin herein may be a crystalline polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. For forming the crystalline polyester, suitable organic diols include aliphatic diols having from about 2 to about 36 carbon atoms, such as 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethylpropane-1,3-diol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, combinations thereof, etc., including their structural isomers. The aliphatic diol may be selected, for example, in an amount of from about 40 mol% to about 60 mol% of the resin, from about 42 mol% to about 55 mol% of the resin, or from about 45 mol% to about 53 mol% of the resin, and the second diol may be selected in an amount of from about 0 mol% to about 10 mol% of the resin or from about 1 mol% to 4 mol% of the resin.

[0036] Examples of the organic dibasic acids or diesters (including vinyl dibasic acids or vinyl diesters) selected for preparing the crystalline resin include oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, dimethyl fumarate, dimethyl itaconate, cis-1,4-diacetoxy-2-butene, diethyl fumarate, diethyl maleate, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, cyclohexanedicarboxylic acid, malonic acid and mesaconic acid, their diesters or acid anhydrides. The organic dibasic acid can be selected, for example, in an amount of about 40 mol% to about 60 mol%, about 42 mol% to about 52 mol% or about 45 mol% to about 50 mol% of the resin, and the second dibasic acid can be selected in an amount of about 0 mol% to about 10 mol% of the resin.

[0037] The polycondensation catalysts useful for forming crystalline (and amorphous) polyesters include tetraalkyl titanates, dialkyltin oxides such as dibutyltin oxide, tetraalkyltins such as dibutyltin dilaurate, and dialkyltin hydroxide such as butyltin hydroxide, aluminum alkoxides, alkylzincs, dialkylzincs, zinc oxide, stannous oxide, or combinations thereof. Based on the starting dibasic acid or diester used to produce the polyester resin, such catalysts can be used, for example, in an amount of about 0.01 mol% to about 5 mol%.

[0038] Examples of crystalline resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutene, polyisobutyrate, ethylene - propylene copolymers, ethylene - vinyl acetate copolymers, polypropylene, mixtures thereof, etc. Specific crystalline resins can be polyester - based, such as poly(ethylene adipate), poly(propylene adipate), poly(butylene adipate), poly(pentylene adipate), poly(hexylene adipate), poly(octylene adipate), poly(ethylene succinate), poly(propylene succinate), poly(butylene succinate), poly(pentylene succinate), poly(hexylene succinate), poly(octylene succinate), poly(ethylene sebacate), poly(propylene sebacate), poly(butylene sebacate), poly(pentylene sebacate), poly(hexylene sebacate), poly(octylene sebacate), poly(decamethylene sebacate), poly(decamethylene decanoate), poly(ethylene decanoate), poly(ethylene dodecanoate), poly(nonamethylene sebacate), poly(nonamethylene decanoate), co - poly(fumaric acid ethylene ester) - co - poly(sebacic acid ethylene ester), co - poly(fumaric acid ethylene ester) - co - poly(decanoic acid ethylene ester), co - poly(fumaric acid ethylene ester) - co - poly(dodecanoic acid ethylene ester), co - poly(2,2 - dimethylpropane - 1,3 - diol - decanoate) - co - poly(nonamethylene decanoate), poly(octylene adipate), and mixtures thereof. Examples of polyamides include poly(ethylene - adipamide), poly(propylene - adipamide), poly(butylene - adipamide), poly(pentylene - adipamide), poly(hexylene - adipamide), poly(octylene - adipamide), poly(ethylene - succinimide), poly(propylene - sebacamide), and mixtures thereof. Examples of polyimides include poly(ethylene - succinimide), poly(propylene - succinimide), poly(butylene - succinimide), poly(pentylene - succinimide), poly(hexylene - succinimide), poly(octylene - succinimide), poly(ethylene - succinimide), poly(propylene - butanimide), poly(butylene - butanimide), and mixtures thereof.

[0039] In an embodiment, the crystalline polyester is represented by the following formula

[0040]

[0041] where each of a and b can be in the range of 1 to 12, 2 to 12, or 4 to 12, and further, where p can be in the range of 10 to 100, 20 to 80, or 30 to 60. In an embodiment, the crystalline polyester is poly(1,6 - hexanediol - 1,12 - dodecanoate), which can be formed by the reaction of dodecanedioic acid with 1,6 - hexanediol.

[0042] As used herein, the designations “CX:CY,” “CX:Y,” “X:Y,” and forms thereof describe a crystalline resin, where C is carbon, X is a positive non-zero integer representing the number of methylene groups of an acid / ester monomer used to produce a crystalline polyester (CPE), and Y is a positive non-zero integer representing the number of methylene groups of an alcohol monomer used to produce the CPE. Thus, for example, C10 can represent, for example, dodecanedioic acid, and C6 can represent, for example, hexanediol. Each of X and Y is 10 or less. In embodiments, the sum of X and Y is 16 or less. In certain embodiments, the sum of X and Y is 14 or less.

[0043] In embodiments, the crystalline polyester is a C10:9 resin, which comprises a polyester made from dodecanedioic acid (C10) and 1,9-nonanediol (C9).

[0044] As described above, the crystalline polyester can be prepared by a polycondensation method by reacting a suitable organic diol with a suitable organic diacid in the presence of a polycondensation catalyst. However, in some cases where the boiling point of the organic diol is from about 180 °C to about 230 °C, a stoichiometric equimolar ratio of the organic diol and the organic diacid can be used, and an excess of diol such as about 0.2 to 1 molar equivalent of ethylene glycol or propylene glycol can be used and removed by distillation during the polycondensation process. The amount of catalyst used can vary and can be selected in an amount such as about 0.01 mol% to about 1 mol% or about 0.1 mol% to about 0.75 mol% of the crystalline polyester resin.

[0045] The crystalline resin can be present in the toner in any suitable or desired amount. In embodiments, the crystalline resin can be present, for example, in an amount of about 1 wt% to about 85 wt% of the toner, about 5 wt% to about 50 wt% of the toner, or about 10 wt% to about 35 wt% of the toner. In certain embodiments, based on the total weight of the toner composition, the crystalline polyester is present in an amount of about 6 wt% to about 7 wt%. In certain embodiments, the crystalline polyester is a C10:9 resin, which is present in the toner in an amount of about 6 wt% to about 7 wt% based on the total weight of the toner composition.

[0046] The crystalline resin can have various melting points, for example, from about 30 °C to about 120 °C, from about 50 °C to about 90 °C, or from about 60 °C to about 80 °C. The crystalline resin can have a number average molecular weight (Mn) measured by gel permeation chromatography (GPC) of, for example, from about 1,000 to about 50,000, from about 2,000 to about 25,000, or from about 5,000 to about 20,000, and a weight average molecular weight (Mw) determined by GPC of, for example, from about 2,000 to about 100,000, from about 3,000 to about 80,000, or from about 10,000 to about 30,000. The molecular weight distribution (Mw / Mn) of the crystalline resin can be, for example, from about 2 to about 6, from about 3 to about 5, or from about 2 to about 4.

[0047] In an embodiment, the toner comprises a core - shell configuration, wherein the core comprises at least one amorphous polyester and at least one crystalline polyester; and wherein the shell comprises at least one amorphous polyester.

[0048] In other embodiments, the toner comprises a core - shell configuration, wherein the core comprises at least one amorphous polyester and at least one crystalline polyester; and wherein the shell comprises a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester.

[0049] In other embodiments, the toner comprises a core - shell configuration, wherein the core comprises a first amorphous polyester containing poly(propoxylated bisphenol - co - terephthalate - fumarate - dodecenyl succinate) and a second amorphous polyester containing poly(propoxylated - ethoxylated bisphenol - co - terephthalate - dodecenyl succinate - trimellitic anhydride).

[0050] In an embodiment, the toner core further comprises a third amorphous polyester resin and a fourth amorphous polyester resin. In an embodiment, the third amorphous polyester resin and the fourth amorphous polyester resin are different. In an embodiment, based on the total weight of the toner, the third amorphous polyester resin is present in an amount of about 1 wt% to about 20 wt%, or about 3 wt% to about 18 wt%, or about 5 wt% to about 15 wt%. In an embodiment, based on the total weight of the toner, the fourth amorphous polyester resin is present in an amount of about 1 wt% to about 20 wt%, or about 3 wt% to about 18 wt%, or about 5 wt% to about 15 wt%. In certain embodiments, the third amorphous polyester is poly(propoxylated bisphenol - co - terephthalate - fumarate - dodecenyl succinate), and the fourth amorphous polyester is poly(propoxylated - ethoxylated bisphenol - co - terephthalate - dodecenyl succinate - trimellitic anhydride).

[0051] In an embodiment, the third amorphous polyester resin and the fourth amorphous polyester resin are present in equal amounts in the toner core.

[0052] In certain embodiments, the toner comprises a core - shell configuration, wherein the shell comprises a resin, and wherein based on the total weight of the toner composition including the core and the shell, the shell resin accounts for about 28 wt% of the toner composition. One or more shell resins accounting for 28% of the toner can be selected from any of the resins described herein. In an embodiment, the shell resin accounts for 28% of the toner particle mass. In an embodiment, wherein the shell resin comprises a combination of two different amorphous polyesters. In an embodiment, wherein the shell comprises a combination of a low - molecular - weight amorphous polyester and a high - molecular - weight amorphous polyester.

[0053] In an embodiment, the amorphous resin may include at least one low molecular weight amorphous polyester resin. The low molecular weight amorphous polyester resin, which can be obtained from multiple sources, may have various melting points, such as from about 30 °C to about 120 °C, in an embodiment from about 75 °C to about 115 °C, in an embodiment from about 100 °C to about 110 °C, or in an embodiment from about 104 °C to about 108 °C. As used herein, the low molecular weight amorphous polyester resin has a number average molecular weight (Mn) of, for example, from about 1,000 to about 10,000, in an embodiment from about 2,000 to about 8,000, in an embodiment from about 3,000 to about 7,000, and in an embodiment from about 4,000 to about 6,000, as measured by gel permeation chromatography (GPC). The weight average molecular weight (Mw) of the resin, as measured by GPC using polystyrene standards, is 50,000 or less, for example, in an embodiment from about 2,000 to about 50,000, in an embodiment from about 3,000 to about 40,000, in an embodiment from about 10,000 to about 30,000, and in an embodiment from about 18,000 to about 21,000. The molecular weight distribution (Mw / Mn) of the low molecular weight amorphous resin is, for example, from about 2 to about 6, in an embodiment from about 3 to about 4. The low molecular weight amorphous polyester resin may have an acid value of from about 8 mg KOH / g to about 20 mg KOH / g, in an embodiment from about 9 mg KOH / g to about 16 mg KOH / g, and in an embodiment from about 10 mg KOH / g to about 14 mg KOH / g.

[0054] In an embodiment, the toner of the present disclosure may further include at least one high molecular weight branched or crosslinked amorphous polyester resin. In an embodiment, the high molecular weight resin may include, for example, a branched amorphous resin or amorphous polyester, a crosslinked amorphous resin or amorphous polyester, or a mixture thereof, or a non-crosslinked amorphous polyester resin that has been crosslinked. According to the present disclosure, from about 1 wt% to about 100 wt% of the high molecular weight amorphous polyester resin may be branched or crosslinked, and in an embodiment, from about 2 wt% to about 50 wt% of the higher molecular weight amorphous polyester resin may be branched or crosslinked.

[0055] As used herein, the high molecular weight amorphous polyester resin may have, for example, a number average molecular weight (Mn) of about 1,000 to about 10,000, in embodiments about 2,000 to about 9,000, in embodiments about 3,000 to about 8,000, and in embodiments about 6,000 to about 7,000, as measured by gel permeation chromatography (GPC). The weight average molecular weight (Mw) of the resin, as measured by GPC using polystyrene standards, is greater than 55,000, for example about 55,000 to about 150,000, in embodiments about 60,000 to about 100,000, in embodiments about 63,000 to about 94,000, and in embodiments about 68,000 to about 85,000. The polydispersity index (PD), as measured by GPC relative to a standard polystyrene reference resin, is higher than about 4, such as for example greater than about 4, in embodiments about 4 to about 20, in embodiments about 5 to about 10, and in embodiments about 6 to about 8. The PD index is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn). The low molecular weight amorphous polyester resin may have an acid value of about 8 mg KOH / g to about 20 mg KOH / g, in embodiments about 9 mg KOH / g to about 16 mg KOH / g, and in embodiments about 11 mg KOH / g to about 15 mg KOH / g. The high molecular weight amorphous polyester resin obtainable from multiple sources may have various melting points of, for example, about 30 °C to about 140 °C, in embodiments about 75 °C to about 130 °C, in embodiments about 100 °C to about 125 °C, and in embodiments about 115 °C to about 121 °C.

[0056] As measured by differential scanning calorimetry (DSC), the high molecular weight amorphous resin obtainable from multiple sources may have various onset glass transition temperatures (Tg) of, for example, about 40 °C to about 80 °C, in embodiments about 50 °C to about 70 °C, and in embodiments about 54 °C to about 68 °C. In embodiments, the linear and branched amorphous polyester resins may be saturated or unsaturated resins.

[0057] The high molecular weight amorphous polyester resin can be prepared by branching or crosslinking a linear polyester resin. Branching agents such as trifunctional or polyfunctional monomers can be used, which generally 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 dianhydride, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, combinations thereof, and the like. These branching agents can be used in an effective amount of about 0.1 mol% to about 20 mol% based on the starting diacid or diester used to prepare the resin.

[0058] Compositions comprising modified polyester resins having polycarboxylic acids that are useful for forming high molecular weight polyester resins include those disclosed in U.S. Patent No. 3,681,106, and branched or crosslinked polyesters derived from polyvalent acids or alcohols, such as those shown in U.S. Patent Nos. 4,863,825, 4,863,824, 4,845,006, 5,143,809, 5,057,596, 4,988,794, 4,981,939, 4,980,448, 4,933,252, 4,931,370, 4,917,983, and 4,973,539, the disclosures of each of these patents being incorporated herein by reference in their entireties.

[0059] In embodiments, the crosslinked polyester resin can be made from a linear amorphous polyester resin that contains unsaturated sites that are reactive under free radical conditions. Examples of such resins include those disclosed in the following U.S. patents: U.S. Patent Nos. 5,227,460, 5,376,494, 5,480,756, 5,500,324, 5,601,960, 5,629,121, 5,650,484, 5,750,909, 6,326,119, 6,358,657, 6,359,105, and 6,593,053, the disclosures of each of these patents being incorporated herein by reference in their entireties. In embodiments, suitable unsaturated polyester matrix resins can be prepared from diacids and / or acid anhydrides (such as, for example, maleic anhydride, terephthalic acid, trimellitic acid, fumaric acid, etc. and combinations thereof) and diols (such as, for example, bisphenol-A ethylene oxide adduct, bisphenol A-propylene oxide adduct, etc. and combinations thereof). In embodiments, a suitable polyester is poly(propoxylated bisphenol A co-fumarate).

[0060] In embodiments, crosslinked branched polyesters can be used as high molecular weight amorphous polyester resins. Such polyester resins can be formed from at least two pre-gelled compositions that comprise at least one polyol having two or more hydroxyl groups or an ester thereof, at least one aliphatic or aromatic polyfunctional acid or an ester thereof, or a mixture thereof having at least three functional groups; and optionally at least one long chain aliphatic carboxylic acid or an ester thereof, or an aromatic monocarboxylic acid or an ester thereof, or a mixture thereof. These two components can be reacted to substantially completion in separate reactors to produce a first composition in a first reactor that comprises a pre-gel having carboxyl end groups, and a second composition in a second reactor that comprises a pre-gel having hydroxyl end groups. The two compositions can then be mixed to form a crosslinked branched polyester high molecular weight resin. Examples of such polyesters and their methods of synthesis include those disclosed in U.S. Patent No. 6,592,913, the disclosure of which is incorporated herein by reference in its entirety.

[0061] Suitable polyols may contain from about 2 to about 100 carbon atoms and have at least two or more hydroxyl groups or their esters. Polyols may include glycerol, pentaerythritol, polyethylene glycol, polyglycerol, etc., or mixtures thereof. Polyols may include glycerol. Suitable glycerol esters include glyceryl palmitate, glyceryl sebacate, glyceryl adipate, glyceryl triacetate, glyceryl tripropionate, etc. The polyol may be present in the reaction mixture in an amount of about 20 wt% to about 30 wt%, and in some embodiments about 22 wt% to about 26 wt% of the reaction mixture.

[0062] Aliphatic polyfunctional acids having at least two functional groups may include saturated and unsaturated acids or their esters containing from about 2 to about 100 carbon atoms, and in some embodiments from about 4 to about 20 carbon atoms. Other aliphatic polyfunctional acids include malonic acid, succinic acid, tartaric acid, malic acid, citric acid, fumaric acid, glutaric acid, adipic acid, pimelic acid, sebacic acid, suberic acid, azelaic acid, sebacic acid, etc., or mixtures thereof. Other aliphatic polyfunctional acids that can be used include dicarboxylic acids containing a C3 to C6 cyclic structure and their positional isomers, and include cyclohexanedicarboxylic acid, cyclobutanedicarboxylic acid, or cyclopropanedicarboxylic acid.

[0063] Aromatic polyfunctional acids having at least two functional groups that can be used include terephthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, and naphthalene 1,4-dicarboxylic acid, naphthalene 2,3-dicarboxylic acid, and naphthalene 2,6-dicarboxylic acid.

[0064] The aliphatic polyfunctional acid or aromatic polyfunctional acid may be present in the reaction mixture in an amount of about 40 wt% to about 65 wt%, and in some embodiments about 44 wt% to about 60 wt% of the reaction mixture.

[0065] Long-chain aliphatic carboxylic acids or aromatic monocarboxylic acids may include those containing from about 12 to about 26 carbon atoms, and in some embodiments from about 14 to about 18 carbon atoms, or their esters. The long-chain aliphatic carboxylic acids may be saturated or unsaturated. Suitable saturated long-chain aliphatic carboxylic acids may include lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, cerotic acid, etc., or combinations thereof. Suitable unsaturated long-chain aliphatic carboxylic acids may include dodecenoic acid, palmitoleic acid, oleic acid, linoleic acid, linolenic acid, erucic acid, etc., or combinations thereof. Aromatic monocarboxylic acids may include benzoic acid, naphthoic acid, and substituted naphthoic acid. Suitable substituted naphthoic acids may include naphthoic acids substituted with straight-chain or branched-chain alkyl groups containing from about 1 to about 6 carbon atoms, such as 1-methyl-2-naphthoic acid and / or 2-isopropyl-1-naphthoic acid. The long-chain aliphatic carboxylic acid or aromatic monocarboxylic acid may be present in the reaction mixture in an amount of about 0 wt% to about 70 wt%, and in some embodiments about 15 wt% to about 30 wt% of the reaction mixture.

[0066] If desired, additional polyols, ionic substances, oligomers, or derivatives thereof may be used. These additional diols or polyols may be present in an amount of from about 0 wt% to about 50 wt% of the reaction mixture. The additional polyols or derivatives thereof may include propylene glycol, 1,3 - butanediol, 1,3 - propanediol, 1,4 - butanediol, 1,6 - hexanediol, diethylene glycol, 1,4 - cyclohexanediol, 1,4 - cyclohexanedimethanol, neopentyl glycol, glyceryl triacetate, trimethylolpropane, pentaerythritol, cellulose ethers, cellulose esters such as cellulose acetate, sucrose acetate isobutyrate, and the like.

[0067] In an embodiment, the cross - linked branched polyesters for high - molecular - weight amorphous polyester resins may include those obtained from the reaction of dimethyl terephthalate, 1,3 - butanediol, 1,2 - propanediol, and pentaerythritol.

[0068] In an embodiment, 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, wherein the high - molecular - weight resin particles have a diameter of from about 100 nanometers to about 300 nanometers, and in an embodiment from about 110 nanometers to about 150 nanometers.

[0069] Whether in any core, in any shell, or in both, the amount of the high - molecular - weight amorphous polyester resin in the toner particles of the present disclosure may be from about 25 wt% to about 50 wt% of the toner, in an embodiment from about 30 wt% to about 45 wt%, and in other embodiments from about 40 wt% to about 43 wt% of the toner (i.e., the toner particles excluding external additives and water).

[0070] The ratio of the crystalline resin to the low - molecular - weight amorphous resin to the high - molecular - weight amorphous polyester resin may range from about 1:1:98 to about 98:1:1 to about 1:98:1, in an embodiment from about 1:5:5 to about 1:9:9, and in an embodiment from about 1:6:6 to about 1:8:8.

[0071] The resin in the toner of the present invention may have acid groups that may be present at the ends of the resin. Acidic groups that may be present include carboxylic acid groups and the like. The number of carboxylic acid groups may be controlled by adjusting the materials used to form the resin and the reaction conditions. In an embodiment, the resin is a polyester resin having an acid value of from about 2 mg KOH / g resin to about 25 mg KOH / g resin, from about 5 mg KOH / g resin to about 20 mg KOH / g resin, or from about 5 mg KOH / g resin to about 15 mg KOH / g resin. The acid - containing resin may be soluble in a tetrahydrofuran solution. The acid value may be detected by titration with a KOH / methanol solution containing phenolphthalein as an indicator. The acid value may then be calculated based on the number of equivalents of KOH / methanol required to neutralize all the acidic groups on the resin identified as the titration endpoint.

[0072] Other exemplary polymers useful for toner resins include styrene acrylates, styrene butadienes, styrene methacrylates, and more specifically, 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(methylstyrene-butadiene), poly(methyl methacrylate-butadiene), 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-acrylonitrile), 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. The polymers can be block copolymers, random copolymers, or alternating copolymers.

[0073] In an embodiment, the resin is selected from the group consisting of styrene, acrylate, methacrylate, butadiene, isoprene, acrylic acid, methacrylic acid, acrylonitrile, and combinations thereof.

[0074] In certain embodiments, the resin is selected from the group consisting of: poly(styrene-butadiene), poly(methyl methacrylate-butadiene), 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-butyl acrylate), poly(styrene-butadiene), poly(styrene-isoprene), poly(styrene-butyl methacrylate), poly(styrene-butyl acrylate-acrylic acid), poly(styrene-butadiene-acrylic acid), poly(styrene-isoprene-acrylic acid), poly(styrene-butyl methacrylate-acrylic acid), poly(butyl methacrylate-butyl acrylate), poly(butyl methacrylate-acrylic acid), poly(styrene-butyl acrylate-acrylonitrile-acrylic acid), poly(acrylonitrile-butyl acrylate-acrylic acid), and combinations thereof.

[0075] Coagulant 。

[0076] The toner of the present invention may also contain a coagulant, such as a monovalent metal coagulant, a divalent metal coagulant, a polyion coagulant, etc. A variety of coagulants are known in the art. As used herein, "polyion coagulant" refers to a coagulant that is a salt or oxide formed from a metal substance having a valence of at least 3 and advantageously at least 4 or 5, such as a metal salt or metal oxide. Thus, suitable coagulants include, for example, aluminum-based coagulants, such as polyhaloaluminum, such as polyfluoroaluminum and polyaluminum chloride (PAC), polysilicoaluminum, such as polysulfosilicoaluminum (PASS), polyaluminum hydroxide, polyaluminum phosphate, etc. Other suitable coagulants include, but are not limited to, tetraalkyl titanates, dialkyltin oxides, tetraalkyltin hydroxides, dialkyltin hydroxides, aluminum alkoxides, alkyl zincs, dialkyl zincs, zinc oxide, stannous oxide, dibutyltin oxide, dibutyltin hydroxide, tetraalkyltin, etc. In the case where the coagulant is a polyion coagulant, the coagulant may have any desired number of polyion atoms present. For example, in an embodiment, a suitable polyaluminum compound may have from about 2 to about 13 or from about 3 to about 8 aluminum ions present in the compound.

[0077] Such coagulants can be incorporated into the toner particles during particle aggregation. Thus, excluding external additives and based on dry weight, the coagulant can be present in the toner particles in an amount of about 0 wt% to about 5 wt% or about greater than 0 wt% to about 3 wt% of the toner particles.

[0078] Surfactant 。

[0079] When preparing the toner by an emulsion aggregation process, one or more surfactants can be used in the method. Suitable surfactants include anionic surfactants, cationic surfactants, and nonionic surfactants. In an embodiment, anionic surfactants and nonionic surfactants are preferably used to help stabilize the aggregation process in the presence of the coagulant, otherwise the presence of the coagulant can lead to aggregation instability.

[0080] Anionic surfactants include sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate, sodium dodecylnaphthalenesulfate, dialkylbenzene alkyl sulfates and sulfonates, rosin acid, and brand anionic surfactants. Examples of suitable anionic surfactants are RK purchased from Daiichi Kogyo Seiyaku co., Ltd. or TAYCA POWERBN2060 mainly composed of branched dodecylbenzenesulfonate purchased from Tayca Corporation (Japan).

[0081] Examples of cationic surfactants include dialkylbenzene alkyl ammonium chloride, lauryl trimethyl ammonium chloride, alkyl benzyl methyl ammonium chloride, alkyl benzyl dimethyl ammonium bromide, benzalkonium chloride, ethyl pyridinium bromide, C12, C15, C17 trimethyl ammonium bromide, halide salts of quaternized polyoxyethyl alkyl amines, dodecyl benzyl triethyl ammonium chloride. and purchased from Alkaril Chemical Company (benzalkonium chloride), etc. Examples of suitable cationic surfactants are B-50 purchased from Kao Corp., which is mainly composed of benzyl dimethyl alkyl ammonium chloride.

[0082] Examples of nonionic surfactants include polyvinyl alcohol, polyacrylic acid, cellulose methyl ether (methalose), 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, dialkylphenoxy poly(ethyleneoxy) ethanol, CA-210, CA-520, CA-720, CO-890, CO-720, CO-290, CA-210, 890 and 897 are purchased from Rhone - Poulenc Inc. Examples of suitable nonionic surfactants are those purchased from Rhone - Poulenc Inc. which mainly consist of alkylphenol ethoxylates.

[0083] Examples of bases used to increase the pH and thus ionize the aggregate particles to provide stability and prevent the growth of aggregate size can be selected from sodium hydroxide, potassium hydroxide, ammonium hydroxide, cesium hydroxide, etc.

[0084] Examples of acids that can be used include, for example, nitric acid, sulfuric acid, hydrochloric acid, acetic acid, citric acid, trifluoroacetic acid, succinic acid, salicylic acid, etc., and in an embodiment, the acid is used in a diluted form in the range of about 0.5 wt% to about 10 wt% in water or in the range of about 0.7 wt% to about 5 wt% in water.

[0085] In an embodiment, a naphthalenesulfonic acid polymer surfactant is selected.

[0086] Optional additives .

[0087] The toner particles may also contain other optional additives as needed. For example, the toner may contain any desired or effective amount of a positive or negative charge control agent, which in embodiments is at least about 0.1 wt% of the toner, or at least about 1 wt% of the toner, or not more than about 10 wt% of the toner, or not more than about 3 wt% of the toner. Examples of suitable charge control agents include, but are not limited to, quaternary ammonium compounds such as alkylpyridinium halides, bisulfates, alkylpyridinium compounds including those disclosed in U.S. Patent 4,298,672, which is hereby incorporated by reference in its entirety; organic sulfate and sulfonate compositions including those disclosed in U.S. Patent 4,338,390, which is hereby incorporated by reference in its entirety; cetylpyridinium tetrafluoroborate; distearyldimethylammonium methyl sulfate; aluminum salts such as BONTRON E84 TM or E88 TM (Hodogaya Chemical); etc., and mixtures thereof. Such charge control agents may be applied simultaneously with the shell resin or after application of the shell resin.

[0088] They may also be blended with external additive particles (including flow aid additives) of the toner particles, which may be present on the surface of the toner particles. Examples of such additives include, but are not limited to, metal oxides such as titanium oxide, silicon oxide, tin oxide, etc., and mixtures thereof; colloidal and amorphous silica such as metal salts and metal salts of fatty acids including zinc stearate, aluminum oxide, cerium oxide, etc., and mixtures thereof. Each of these external additives may be present in any desired or effective amount, which in embodiments is at least about 0.1 wt% of the toner, or at least about 0.25 wt% of the toner, or not more than about 5 wt% of the toner, or not more than about 3 wt% of the toner. Suitable additives include, but are not limited to, those disclosed in U.S. Patents 3,590,000 and 6,214,507, each of which is hereby incorporated by reference in its entirety. These additives may be applied simultaneously with the shell resin or after application of the shell resin.

[0089] Emulsion aggregation polyester toners typically use about 7.2 parts per hundred (pph) of TaycaPower B2060 surfactant, which is the sodium salt of dodecylbenzenesulfonic acid, as the dispersant for the carbon black dispersion in the toner. in the toner.

[0090] In an embodiment, the amount of TaycaPower surfactant in the pigment dispersion can be reduced to only 2 pph while adding 3.2 pph of DEMOL SN-B, which is a polymeric surfactant of butylnaphthalenesulfonic acid / 2-naphthalenesulfonic acid / formaldehyde sodium salt (Kao Corporation). The dispersion can then be used to prepare a toner.

[0091] Similar products can be used to reduce dielectric loss. For example: DEMOL M (aryl sulfonate formaldehyde condensate powder), DEMOL SS-L (aryl sulfonate formaldehyde condensate), DEMOL N, DEMOL RN, DEMOL T, and DEMOL T-45 (naphthalene sulfonate formaldehyde condensate powder), DEMOL NL (naphthalene sulfonate formaldehyde condensate liquid). Other manufacturers offer similar sulfonate formaldehyde condensates, such as 1-naphthalenesulfonic acid, formaldehyde polymer, sodium salt, product catalog number 32844-36-3, purchased from Anyang Double Circle Auxiliary Co., LTD, China; and naphthalene sulfonate formaldehyde, product catalog number 9084-06-4, purchased from Chemtrade International, China.

[0092] Colorant 。

[0093] The toner can optionally contain a colorant. Any suitable or desired colorant can be selected. In an embodiment, the colorant can be a pigment, a dye, a mixture of a pigment and a dye, a mixture of pigments, a mixture of dyes, etc. For simplicity, unless specified as a particular pigment or other colorant component, the term "colorant" as used herein is intended to encompass such colorants, dyes, pigments, and mixtures. In an embodiment, the colorant comprises a pigment, a dye, a mixture thereof, in an embodiment carbon black, magnetite, black, cyan, magenta, yellow, red, green, blue, brown, a mixture thereof, in an amount of from about 1 wt% to about 25 wt% based on the total weight of the toner composition. In an embodiment, the colorant is selected from cyan, magenta, yellow, black, or a combination thereof. In certain embodiments, the colorant comprises a combination of carbon black and cyan. It should be understood that other available colorants will become apparent based on the present disclosure.

[0094] In certain embodiments, based on the total weight of the toner composition, the colorant comprises a pigment present in an amount of from about 5 wt% to about 8 wt%.

[0095] Available colorants include Violet 5100 and 5890 (BASF), Normandy Magenta RD-2400 (Paul Uhlrich), Permanent Violet VT2645 (Paul Uhlrich), Green L8730 (BASF), Argyle Green XP-111-S (Paul Uhlrich), Brilliant Green Toner GR 0991 (Paul Uhlrich), Scarlet D3700 (BASF), Toluidine Red (Aldrich), Scarlet for Thermoplast NSD Red (Aldrich), Rubine Toner (Paul Uhlrich), Scarlet 4440, NBD 3700 (BASF), Bon Red C (Dominion Color), Royal Brilliant Red RD-8192 (Paul Uhlrich), Pink RF (Ciba Geigy), Red 3340 and 3871K (BASF), Fast Scarlet L4300 (BASF), Blue D6840, D7080, K7090, K6910 and L7020 (BASF), Sudan Blue OS (BASF), Blue FF4012 (BASF), PV Fast Blue B2G01 (American Hoechst), Blue BCA (Ciba Geigy), Blue 6470 (BASF), Sudan II, III and IV (Matheson, Coleman, Bell), Sudan Orange (Aldrich), Sudan Orane 220 (BASF), Orange 3040 (BASF), Ortho Orange OR 2673 (Paul Uhlrich), Yellow 152 and 1560 (BASF), Fast Yellow 0991K (BASF), Yellow 1840 (BASF), Yellow FGL (Hoechst), Permanent Yellow YE 0305 (Paul Uhlrich), Yellow 00790 (BASF), Suco-Gelb 1250 (BASF), Suco-Yellow D1355 (BASF), Suco Fast Yellow D1165, D1355 and D1351 (BASF), Pink E (Hoechst), Pink D4830 (BASF), Magenta (DuPont), Black L9984 (BASF), Pigment Black K801 (BASF), and specifically carbon blacks such as 330 (Cabot), Carbon Black 5250 and 5750 (Columbian Chemicals), etc., or mixtures thereof.

[0096] Other available colorants include pigments in aqueous dispersions, such as those commercially available from Sun Chemical, e.g., BHD 6011X (Blue 15 type), BHD 9312X (Pigment Blue 15:74160), BHD 6000X (Pigment Blue 15:3 74160), GHD 9600X and GHD 6004X (Pigment Green 7 74260), QHD 6040X (Pigment Red 122 73915), RHD 9668X (Pigment Red 185 12516), RHD 9365X and 9504X (Pigment Red 57 15850:1), YHD 6005X (Pigment Yellow 83 21108), YFD4249 (Pigment Yellow 17 21105), YHD 6020X and 6045X (Pigment Yellow 74 11741), YHD 600X and 9604X (Pigment Yellow 14 21095), LFD 4343 and LFD 9736 (Pigment Black 7 77226), etc., or mixtures thereof. Other available water-based colorant dispersions include those commercially available from Clariant, such as Yellow GR, Black T and Black TS, Blue B2G, Rubine F6B, and magenta dry pigments such as Toner Magenta 6BVP2213 and Toner Magenta EO2, which can be dispersed in water and / or surfactant before use.

[0097] Other available colorants include magnetite, such as Mobay magnetite M08029, M98960, Columbian magnetite, BLACKS and surface-treated magnetite; Pfizer magnetite CB4799, CB5300, CB5600, MXC6369, Bayer magnetite 8600, 8610; Northern Pigments magnetite NP-604, NP-608; Magnox magnetite TMB-100 or TMB-104, etc., or mixtures thereof. Additional examples of pigments include phthalocyanine BLUE L6900, D6840, D7080, D7020, OIL BLUE, OILYELLOW, PIGMENT BLUE 1, PIGMENT VIOLET 1, PIGMENTRED 48, LEMON CHROME YELLOW DCC 1026, ED.TOLUIDINE RED purchased from Paul Uhlrich & Company, Inc., and BON RED C, YELLOW FGL, obtained from Hoechst PINK E, and Examples of magenta include 2,9-dimethyl-substituted quinacridone and anthraquinone dye C.I. Disperse Red 15 identified as C.I. 60710 in the Color Index, diazo dye C.I. Solvent Red 19 identified as C.I. 26050 in the Color Index, etc., or mixtures thereof. Examples of cyan include copper phthalocyanine tetrakis(octadecylsulfonamide), x-copper phthalocyanine pigment C.I. Pigment Blue listed as C.I. 74160 in the Color Index, and Anthrathrene Blue Special Blue X-2137 identified as D.I. 69810 in the Color Index, etc., or mixtures thereof. Exemplary examples of optional yellow include benzidine yellow 3,3-dichlorobenzidine acetoacetanilide, monoazo pigment C.I. Solvent Yellow 16 identified as C.I. 12700 in the Color Index, nitro phenylamine sulfonamide C.I. Disperse Yellow 33 identified as Foron Yellow SE / GLN in the Color Index, 2,5-dimethoxy-4-sulfonanilide, phenylazo-4'-chloro-2,4-dimethoxyacetoacetanilide, and Permanent Yellow FGL. Also optionally colored magnetite such as a mixture of BLACK and cyan components as a pigment.

[0098] Colorants (such as carbon black, cyan, magenta, and / or yellow colorants) are incorporated in an amount sufficient to impart the desired color to the toner. Generally, the pigment or dye is used in an amount of about 1 wt% to about 35 wt%, or about 5 wt% to about 25 wt%, or about 5 wt% to about 15 wt% of the toner particles based on solids. However, amounts outside of these ranges may also be used.

[0099] In an embodiment, the toner contains a carbon black colorant. Some emulsion aggregation toners include 35 non-oxidized low structure furnace black, while other emulsion aggregation toners use 330. To achieve the lowest possible dielectric loss, low conductivity carbon black is selected, such as 35. Since carbon black is a semiconductor, it is desirable to keep the carbon black as pure as possible. Heteroatoms such as oxygen and sulfur dope the carbon black semiconductor, thus increasing the conductivity. As determined by XPS, 35 has an extremely high carbon content of >99.5% and a total of <0.5% of extremely low O and S atomic % on the surface. Since the carbon black is very pure and has few strong dopants oxygen and sulfur on the surface, the conductivity is very low. This provides a lower dielectric loss than less pure carbon black (such as which has >1% oxygen and sulfur). The difference in purity is most significantly shown by the carbon:oxygen ratio of the carbon black, The carbon:oxygen ratio of 35 is 499:1, while the carbon:oxygen ratio of 330 is 139:1.

[0100] In an embodiment, the colorant comprises a combination of carbon black and cyan (in an embodiment, cyan PB 15:3).

[0101] In an embodiment, the toner comprises 5 wt% to 8 wt% of a pigment. In certain embodiments, the toner comprises: 5 wt% to 8 wt% of a pigment, wherein the pigment comprises a combination of carbon black and cyan; 73 wt% to 78 wt% of an amorphous polyester, wherein the amorphous polyester comprises a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester; 6 wt% to 7 wt% of a crystalline polyester, in an embodiment, wherein the crystalline polyester is a C10:C9 crystalline polyester, wherein the wt% is based on the total weight of the toner composition. In an embodiment, based on the total weight of the toner composition, the toner comprises a cyan pigment present in an amount of about 1 wt% and a carbon black pigment present in an amount of about 6.9 wt%.

[0102] In other embodiments, the toner comprises a colorant that comprises a combination of two or more of cyan (in an embodiment, cyan PB15:3), magenta (in an embodiment, one or both of magenta PR269 and magenta RE05), yellow (in an embodiment, yellow PY74), and carbon black. In other embodiments, the toner comprises 5% to 8% of a pigment that comprises a combination of two or more of cyan (in an embodiment, cyan PB 15:3), magenta (in an embodiment, one or both of magenta PR269 and magenta RE05), yellow (in an embodiment, yellow PY74), and carbon black.

[0103] Wax .

[0104] Optionally, a wax may also be combined with the resin to form toner particles. When included, the wax may be present, for example, in an amount of about 1 wt% to about 25 wt% of the toner particles, in an embodiment about 5 wt% to about 20 wt% of the toner particles.

[0105] Waxes that may be selected include, for example, waxes having a weight average molecular weight of about 500 to about 20,000, in an embodiment about 1,000 to about 10,000. Waxes that may be used include, for example, polyolefins such as polyethylene, polypropylene, and polybutene waxes, such as those commercially available from Allied Chemical and Petrolite Corporation, for example POLYWAX available from Baker Petrolite TMPolyethylene wax, wax emulsions purchased from Michaelman, Inc. and Daniels Products Company, and EPOLENE N-15 commercially available from Eastman Chemical Products, Inc. TM and VISCOL550-P purchased from Sanyo Kasei K.K. TM (low weight average molecular weight polypropylene); plant-based waxes such as carnauba wax, rice wax, candelilla wax, sumac wax, and jojoba oil; animal-based waxes such as beeswax; mineral-based waxes and petroleum-based 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 octadecyl stearate and docosyl docosanoate; ester waxes obtained from higher fatty acids and monovalent or polyvalent lower alcohols such as butyl stearate, propyl oleate, glycerol monostearate, glycerol distearate, and pentaerythritol tetracosanoate; ester waxes obtained from higher fatty acids and polyhydric alcohol polymers such as diethylene glycol monostearate, dipropylene glycol distearate, diglycerol distearate, and triglycerol tetrastearate; dehydrated sorbitol higher fatty acid ester waxes such as sorbitan monostearate, and cholesterol higher fatty acid ester waxes such as cholesteryl stearate. Examples of functionalized waxes that can be used include, for example, amines; amides such as AQUA SUPERSLIP 6550 purchased from Micro Powder Inc. TM and SUPERSLIP 6530 TM ; fluorinated waxes such as POLYFLUO 190 purchased from MicroPowder Inc. TM and POLYFLUO 200 TM and POLYSILK 19 TM and POLYSILK 14 TM ; mixed fluorinated amide waxes such as MICROSPERSION 19 also purchased from Micro Powder Inc. TM ; imides, esters, quaternary amines, carboxylic acids, or acrylic polymer emulsions such as JONCRYL 74 TM , 89 TM , 130 TM , 537 TM and 538 TM ; and chlorinated polypropylenes and polyethylenes purchased from Allied Chemical and Petrolite Corporation, and SC Johnson wax. Mixtures and combinations of the aforementioned waxes can also be used in the embodiments. The wax can be included, for example, as a fuser roll release agent.

[0106] In certain embodiments, the toner herein can be a dual-wax toner as described in U.S. Patent Application No. 16 / 800,176 (Attorney Docket No. 20190262US01), which patent application is hereby incorporated by reference in its entirety. In an embodiment, the toner composition comprises a first wax; a second wax different from the first wax; wherein the first wax comprises paraffin wax; wherein the second wax comprises polymethylene wax; at least one polyester; and optionally a colorant.

[0107] Surface additive formulation 。

[0108] In an embodiment, the toner herein comprises mother toner particles, which mother toner particles comprise at least one resin combined with an optional colorant, and an optional wax. The resin, colorant, and wax are each independently selected from those described herein. In an embodiment, the toner comprises a surface additive formulation provided on the mother toner particles, the surface additive formulation comprising at least one medium silica surface additive having a volume average primary particle size of 30 nanometers to 50 nanometers, the at least one medium silica being provided at a surface area coverage of 40% to 100% of the surface area of the mother toner particles; at least one large silica surface additive having a volume average primary particle size of 80 nanometers to 120 nanometers, the at least one large silica being provided at a surface area coverage of 5% to 29% of the surface area of the mother toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having a volume average primary particle size of 15 nanometers to 40 nanometers, the titanium dioxide being present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the mother toner particles; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 5% to 75% of the surface area of the mother toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 0% to 75% of the surface area of the mother toner particles; and wherein the total surface area coverage of all the combined surface additives is 100% to 140% of the surface area of the mother toner particles. In an embodiment, (b) the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, or 8 nanometers to 25 nanometers, or 8 nanometers to 21 nanometers. The average primary particle size is the volume D50 diameter measured by the additive manufacturer or supplier. The method for measuring the particle size is SEM (scanning electron microscopy) or TEM (transmission electron microscopy). In some cases, an indirect method such as dynamic light scattering DLS may be used. Examples of suitable DLS devices include Nanotrac Wave and Nanotrac Wave II.

[0109] In an embodiment, the percentage of the surface area coverage (SAC) of the additive relative to the surface area of the toner mother particles can be calculated as:

[0110] SAC = 100●(w●D●P) / (0.363●d●p)

[0111] Wherein, for the toner mother particles, D is the D50 volume average size in microns, and P is the true bulk density in g / cm 3 3; and wherein, for the toner surface additive, d is the D50 volume average particle size in nanometers, p is the true bulk density in g / cm 3 3, and w is the weight of the toner surface additive added to the mixture in parts per hundred parts based on the toner mother particles.

[0112] As used herein, medium silica refers to silica having an average volume primary particle size of 30 nanometers to 50 nanometers.

[0113] In an embodiment, the medium silica has a hydrophobic treatment agent. In an embodiment, the hydrophobic treatment agent comprises polydimethylsiloxane (HMDS). In an embodiment, the hydrophobic treatment agent comprises an alkylsilane, such as hexamethyldisilazane (HMDS). The medium silica can be treated medium pyrogenic silica, such as those available under the trade name Wacker HO5TD (40nm, PDMS), HO5TM (40nm, HMDS), HO5TX (40nm, HMDS / PDMS); those obtained from Evonik NY50 (30nm, PDMS), NAX50 (30nm, HMDS), RY50 (40nm, PDMS) and RX50 (40nm, HMDS).

[0114] In the case where the mother toner particles have 100% of the total surface area, in an embodiment, the medium silica is provided with a surface area coverage of 40% to 100% of the surface area of the mother toner particles.

[0115] In certain embodiments, the at least one medium silica comprises two or more medium silicas, wherein the two or more medium silicas include surface-treated medium silicas selected from the group consisting of: silica treated with an alkylsilane, silica treated with polydimethylsiloxane, and combinations thereof.

[0116] In certain embodiments, the at least one medium silica includes a first medium silica and a second medium silica, the first medium silica being silica treated with an alkylsilane and the second medium silica being silica treated with polydimethylsiloxane.

[0117] As used herein, large silica refers to silica having a volume average primary particle size of from 80 nanometers to 120 nanometers.

[0118] In the case where the mother toner particles have 100% total surface area, in an embodiment, the large silica is provided at a surface area coverage of from 5% to 29% of the surface area of the mother toner particles.

[0119] The large silica can be large silica obtained from Shin Etsu Chemical under the trade name X24-9163A or from Cabot Corporation under the name TG-C191.

[0120] The surface additive formulation comprises at least one positively charged surface additive.

[0121] In an embodiment, the surface additive formulation comprises at least one positively charged surface additive, and the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having a volume average primary particle size of from 15 nanometers to 40 nanometers, and based on 100 parts of the mother toner particles, the titanium dioxide is present in an amount of less than or equal to 1 part per hundred parts; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of from 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage of from 5% to 75% of the surface area of the mother toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of from 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of from 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of from 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage of from 0% to 75% of the surface area of the mother toner particles. In an embodiment, the positively charged non-titanium dioxide metal oxide surface additive is a metal oxide comprising at least one member selected from the group consisting of Bronsted bases, Lewis bases, and amphoteric compounds.

[0122] In an embodiment, the toner surface additive formulation is free of titanium dioxide, i.e., does not contain titanium dioxide or contains a lesser amount of titanium dioxide than previously known toner additive formulations. In an embodiment, the toner additive formulation contains a titanium dioxide surface additive having an average primary particle size of 15 nanometers to 40 nanometers, and the titanium dioxide is present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the parent toner particles. In this embodiment, the toner additive formulation further contains small silica having a volume average primary particle diameter of 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage of 5% to 75% of the surface area of the parent toner particles.

[0123] The titanium dioxide can be selected from any suitable or desired titanium dioxide having the desired particle size, such as JMT-150IB having a volume average particle diameter of 15 nanometers from Tayca Corp., JMT2000 having a particle size of 15x15x40 nanometers from Tayca Corp., T805 having a volume average particle diameter of about 21 nanometers from Evonik, SMT5103 having a particle size of about 40 nanometers from Tayca Corporation, and STT-100H having an average particle size of about 40 nanometers from Inabata America Corporation. See U.S. Patents 8,163,450, 8,916,317, 8,507,166, and 7,300,734, each of which is hereby incorporated by reference in its entirety.

[0124] As used herein, small silica refers to silica having an average volume primary particle diameter of 8 nanometers to 16 nanometers.

[0125] In the case where the parent toner particles have 100% total surface area, in an embodiment, the small silica is provided at a surface area coverage of 0% to 75% of the surface area of the parent toner particles, or in an embodiment at 5% to 75% of the surface area of the parent toner particles, or at 30% to 75% of the surface area of the parent toner particles.

[0126] The small silica can be selected from any suitable or desired silica having the desired particle size, such as RY200L purchased from Evonik Industries. In an embodiment, the small silica is selected from the group consisting of silica treated with an alkylsilane, silica treated with polydimethylsiloxane, and combinations thereof. In an embodiment, the small silica includes treated silica Wacker H13TD(16nm, PDMS), H13TM(16nm, HMDS), H13TX(16nm, HMDS / PDMS), H20TD (12 nm, PDMS), H20TM (12 nm, HMDS), H20TX (12 nm, HMDS / PDMS), H30TD (8 nm, PDMS), H30TM (8 nm, HMDS), H30TX (8 nm, HMDS / PDMS), H3004 (12 nm, HMDS); Evonik R972 (16 nm, DDS), RY200S (16 nm, PDMS), 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 (8 nm, HMDS), R812 (8 nm, HMDS), R812S (8 nm, HMDS), and R106 (8 nm, alkylsilane); and Cabot TS530 (8 nm, HMDS).

[0127] In an embodiment, the toner surface additive formulation comprises a positively charged non-titanium dioxide metal oxide surface additive. The positively charged non-titanium dioxide metal oxide surface additive can be any suitable metal oxide additive that provides a positive charge. Positively charged metal oxide additives can be so identified by the additive manufacturer or additive supplier. In an embodiment, an additive that is a Bronsted base or a Lewis base is a suitable positively charged metal oxide additive. Suitable positively charged metal oxide additives also include amphoteric compounds. Amphoteric means that the substance has both acidic and basic groups such that the compound can function as a Bronsted or Lewis acid and base. In an embodiment, the positively charged metal oxide surface additive comprises at least one member of the group consisting of Bronsted bases, Lewis bases, and amphoteric compounds. Not suitable for being positively charged are pure acidic compounds such as silica. In some embodiments, silica can be treated with a basic or amphoteric surface treatment agent such that it is suitable for use as a positively charged metal oxide additive. Examples of such basic treatment agents are, for example, NR2 / NR3 +Group, where R is an alkyl group in the embodiments, such as those in Wacker's positively charged silica. One such known positively charged treating agent for silica that has basic functional groups is aminopropyltriethoxysilane. Basic or amphoteric metal oxides include those metal oxides with an oxidation state of 3 for amphoteric oxides or an oxidation state of 2 for basic oxides. It should be noted that some metal oxides with an oxidation state of 2 can be considered amphoteric. Thus, both TiO2 and ZnO2 are basic oxides, but they still have some amphoteric characteristics. Other examples of basic metal oxides with an oxidation state of 2 include CaO, MgO, FeO, CrO, and MnO. Examples of amphoteric inorganic materials suitable as positive additives are BeO, Al2O3, GA2O3, In2O3, Tl2O3, GeO2, SnO, SnO2, PbO, PBO2, As2O3, Sb2O3, Bi2O3, and Fe2O3. Titanates are oxides composed of two different metals, namely titanium in the +2 or +4 oxidation state and another metal in the +2 oxidation state. Ti in the +4 oxidation state is acidic, but the metal in the +2 oxidation state is basic. Thus, titanates based on Ti+4 are amphoteric and are suitable as positively charged metal oxide additives in the embodiments. Examples of suitable titanates include CaTiO3, BaTiO3, MgTiO3, MnTiO3, and SrTiO3. Aluminum titanate Al2TiO5 (Al in the +3 oxidation state, Ti in the +2 oxidation state) is amphoteric and is also suitable as a positively charged metal oxide additive. In the embodiments, the positively charged non-titanium dioxide metal oxide surface additives are selected from the group consisting of alumina, strontium titanate, alumina treated with an alkylsilane, alumina treated with polydimethylsiloxane, and combinations thereof. In the embodiments, the positively charged non-titanium dioxide surface additives are selected from the group consisting of alumina, strontium titanate, and combinations thereof. In the embodiments, the positively charged non-titanium dioxide surface additive is alumina. In the embodiments, the positively charged non-titanium dioxide metal oxide additive is an additive containing a nitrogen-containing molecular structure. In the embodiments, the positively charged non-titanium dioxide metal oxide surface additive is silica treated with a basic or amphoteric surface treating agent.

[0128] The positively charged non-titanium dioxide metal oxide surface additives can be surface treated. In the embodiments, the positively charged non-titanium dioxide metal oxide surface additives are selected from the group consisting of alumina treated with an alkylsilane, alumina treated with polydimethylsiloxane, and combinations thereof. In a specific embodiment, the alkylsilane treating agent of the positively charged non-titanium dioxide metal oxide surface additive can include amino groups, such as, for example, amines, imides, or amides. In the embodiments, specific positively charged surface additives include Wacker-treated silica H13TA (16 nm, PDMS-NR2 / NR3 + )、 H30TA (8 nm, PDMS-NR2 / NR3 + ); H2015EP (12 nm, PDMS-NR2 / NR3 + ); H2050EP (10 nm, PDMS-NR2 / NR3 + ); H2150VP (10 nm, PDMS-NR2 / NR3 + ); H3050VP (8 nm, PDMS-NR2 / NR3 + );Cabot TG-820F (8 nm); Evonik C805 (13 nm, octylsilane), Aluminum Oxide C (13 nm, untreated), Aeroxide Alu C 100 (10 nm, untreated), AeroxideAlu C 130 (13 nm, untreated); Cabot SpectrAL 81 (21 nm, untreated) and Cabot SpectrAl 100 (18 nm, untreated).

[0129] In an embodiment, the total surface area coverage of all the combined surface additives is 100% to 140% of the surface area of the parent toner particles. The parent toner particles are toner particles without external additives.

[0130] Toner preparation .

[0131] The toner particles can be prepared by any method within the capabilities of those skilled in the art. Although embodiments related to the preparation of the toner particles are described below for the emulsion aggregation process, any suitable method for preparing toner particles can be used, including chemical processes, such as the suspension and encapsulation processes disclosed in U.S. Patent Nos. 5,290,654 and 5,302,486, the disclosures of each of these patents being hereby incorporated by reference in their entireties. In an embodiment, the toner composition and the toner particles can be prepared by an aggregation and coalescence method, where small-sized resin particles are aggregated into an appropriate toner particle size and then coalesced to achieve the final toner particle shape and morphology.

[0132] In an embodiment, the toner composition can be prepared by an emulsion aggregation method, such as a method including aggregating a mixture of an optional wax and any other desired or required additives, optionally in a surfactant as described above, and an emulsion containing the above resin, and then coalescing the aggregate mixture. The mixture can be prepared by adding an optional wax or other material to the emulsion, and the optional wax or other material can also optionally be present in the dispersion containing the surfactant. The emulsion can be a mixture of two or more emulsions containing the resin. The pH of the resulting mixture can be adjusted with an acid such as, for example, acetic acid, nitric acid, etc. In an embodiment, the pH of the mixture can be adjusted to about 2 to about 4.5. Additionally, in an embodiment, the mixture can be homogenized. If the mixture is homogenized, the homogenization can be achieved by mixing at about 600 revolutions per minute to about 4,000 revolutions per minute. The homogenization can be achieved by any suitable device, including, for example, IKA ULTRA T50 probe homogenizer.

[0133] After preparing the above mixture, a flocculant can be added to the mixture. Any suitable flocculant can be utilized to form the toner. Suitable flocculants include, for example, aqueous solutions of divalent or polyvalent cationic materials. The flocculant can be, for example, polyaluminum halides such as polyaluminum chloride (PAC) or the corresponding bromide, fluoride, or iodide, polysilicate aluminum such as polysulfide silicate aluminum (PASS), and water-soluble metal salts, including aluminum chloride, aluminum nitrite, aluminum sulfate, potassium alum, calcium acetate, calcium chloride, calcium nitrite, calcium oxalate, 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 an embodiment, the flocculant can be added to the mixture at a temperature below the glass transition temperature (Tg) of the resin.

[0134] The flocculant can be added to the mixture for forming the toner in an amount of, for example, about 0.1 wt% to about 8 wt% of the resin in the mixture, about 0.2 wt% to about 5 wt% in an embodiment, and about 0.5 wt% to about 5 wt% in other embodiments. This provides a sufficient amount of reagent for aggregation.

[0135] To control the aggregation and coalescence of particles, in embodiments, a flocculant may be metered into the mixture over time. For example, the reagent may be metered into the mixture over a time period of from about 5 minutes to about 240 minutes, in embodiments from about 30 minutes to about 200 minutes. The addition of the reagent may also be carried out while the mixture is maintained under stirring conditions, which are in embodiments from about 50 rpm to about 1,000 rpm, in other embodiments from about 100 rpm to about 500 rpm, and at a temperature below the glass transition temperature of the resin as described above, which is in embodiments from about 30 °C to about 90 °C, in embodiments from about 35 °C to about 70 °C.

[0136] The particles may be aggregated until a predetermined desired particle size is obtained. The predetermined desired particle size refers to the desired particle size that will be obtained as determined prior to formation, and the particle size is monitored during the growth process until that particle size is reached. Samples may be taken during the growth process and the average particle size analyzed, for example, using a Coulter counter. Thus, aggregation may be carried out by maintaining an elevated temperature or slowly raising the temperature to, for example, from about 40 °C to about 100 °C and holding the mixture at that temperature for from about 0.5 hours to about 6 hours, in embodiments from about 1 hour to about 5 hours, while maintaining stirring, thereby obtaining aggregated particles. Once the predetermined desired particle size is reached, the growth process is stopped. In embodiments, the predetermined desired particle size is within the toner particle size range described above.

[0137] The growth and shaping of the particles after the addition of the flocculant may be achieved under any suitable conditions. For example, the growth and shaping may be carried out under conditions where aggregation and coalescence occur separately. For separate aggregation and coalescence stages, the aggregation process may be carried out under shear conditions at an elevated temperature, for example, from about 40 °C to about 90 °C, in embodiments from about 45 °C to about 80 °C, which temperature may be below the glass transition temperature of the resin as described above.

[0138] In embodiments, a shell may be applied to the aggregated particles after aggregation but before coalescence.

[0139] Resins that may be used to form the shell include, but are not limited to, the amorphous resins described above for the core. Such amorphous resins may be low molecular weight resins, high molecular weight resins, or combinations thereof. In embodiments, the amorphous resin that may be used to form the shell according to the present disclosure may include the amorphous polyester of formula I above.

[0140] In some embodiments, the amorphous resin used to form the shell can be crosslinked. For example, crosslinking can be achieved by combining the amorphous resin with a crosslinking agent (sometimes referred to herein as an initiator). Examples of suitable crosslinking agents include, but are not limited to, for example, free radical initiators or thermal initiators, such as the organic peroxides and azo compounds described above that are suitable for forming a gel in the core. Examples of suitable organic peroxides include diacyl peroxides, such as, for example, decanoyl peroxide, lauroyl peroxide, and benzoyl peroxide; ketone peroxides, such as, for example, cyclohexanone peroxide and methyl ethyl ketone peroxide; alkyl peroxide esters, such as, for example, tert-butyl peroxyneodecanoate, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxyacetate, tert-amyl peroxyacetate, tert-butyl peroxybenzoate, tert-amyl peroxybenzoate, o,o-tert-butyl o-isopropyl monoperoxycarbonate, 2,5-dimethyl 2,5-bis(benzoylperoxy)hexane, o,o-tert-butyl o-(2-ethylhexyl) monoperoxycarbonate, and o,o-tert-amyl o-(2-ethylhexyl) monoperoxycarbonate; alkyl peroxides, such as, for example, dicumyl peroxide, 2,5-dimethyl 2,5-bis(tert-butylperoxy)hexane, tert-butyl cumene peroxide, α,α-bis(tert-butylperoxy)diisopropylbenzene, di-tert-butyl peroxide, and 2,5-dimethyl 2,5-bis(tert-butylperoxy)hex-3-yne; alkyl hydroperoxides, such as, for example, 2,5-dihydroperoxy-2,5-dimethylhexane, cumene hydroperoxide, tert-butyl hydroperoxide, and tert-amyl hydroperoxide, and alkyl peroxyketals, such as, for example, n-butyl 4,4-bis(tert-butylperoxy)valerate, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-butylperoxy)cyclohexane, 1,1-bis(tert-amylperoxy)cyclohexane, 2,2-bis(tert-butylperoxy)butane, ethyl 3,3-bis(tert-butylperoxy)butyrate, and ethyl 3,3-bis(tert-amylperoxy)butyrate, and combinations thereof. Examples of suitable azo compounds include 2,2'-azobis(2,4-dimethylvaleronitrile), azodi-isobutyronitrile, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(methylbutyronitrile), 1,1'-azobis(cyanocyclohexane), other similar known compounds, and combinations thereof.

[0141] The crosslinking agent and the amorphous resin can be combined at a sufficient temperature for a sufficient time to form a crosslinked polyester gel. In an embodiment, the crosslinking agent and the amorphous resin can be heated to a temperature of about 25°C to about 99°C, in an embodiment about 30°C to about 95°C, for a period of about 1 minute to about 10 hours, in an embodiment about 5 minutes to about 5 hours, to form a crosslinked polyester resin or polyester gel suitable for use as a shell.

[0142] In use, the crosslinking agent may be present in an amount of from about 0.001 wt% to about 5 wt% of the resin, and in embodiments from about 0.01 wt% to about 1 wt% of the resin. In the presence of a crosslinking agent or initiator, the amount of CCA may be reduced.

[0143] A single polyester resin may be used as the shell, or as described above, in embodiments, the first polyester resin may be combined with other resins to form the shell. The various resins may be used in any suitable amounts. In embodiments, the first amorphous polyester resin, such as the low molecular weight amorphous resin of formula I above, may be present in an amount of from about 20 wt% to about 100 wt% of the total shell resin, and in embodiments from about 30 wt% to about 90 wt% of the total shell resin. Thus, in embodiments, the second resin, in embodiments the high molecular weight amorphous resin, may be present in the shell resin in an amount of from about 0 wt% to about 80 wt% of the total shell resin, and in embodiments from about 10 wt% to about 70 wt% of the shell resin.

[0144] After aggregating to the desired particle size and applying any optional shell, the particles may then be coalesced into the desired final shape, which is achieved, for example, by heating the mixture to a temperature of from about 45 °C to about 100 °C, and in embodiments from about 55 °C to about 99 °C (this temperature may be at or above the glass transition temperature of the resin used to form the toner particles) and / or reducing the stirring speed to, for example, from about 100 rpm to about 400 rpm, and in embodiments from about 200 rpm to about 300 rpm. The shape factor or roundness of the fixed particles may be measured, such as with a SYSMEX FPIA 2100 analyzer, until the desired shape is achieved.

[0145] Coalescence may be achieved over a period of from about 0.01 hours to about 9 hours, and in embodiments from about 0.1 hours to about 4 hours.

[0146] In embodiments, after aggregation and / or coalescence, the pH of the mixture may then be reduced to from about 3.5 to about 6, and in embodiments to from about 3.7 to about 5.5, with an acid, such as nitric acid, sulfuric acid, hydrochloric acid, citric acid, and / or acetic acid, to further coalesce the toner aggregates. The amount of acid added may be from about 0.1 wt% to about 30 wt% of the mixture, and in embodiments from about 1 wt% to about 20 wt% of the mixture.

[0147] The mixture may be cooled, washed, and dried. Cooling may be carried out at a temperature of from about 20 °C to about 40 °C, and in embodiments from about 22 °C to about 30 °C, over a period of from about 1 hour to about 8 hours, and in embodiments from about 1.5 hours to about 5 hours.

[0148] In an embodiment, the cooled coalesced toner slurry can be quenched by adding a cooling medium such as, for example, ice, dry ice, etc. to achieve rapid cooling to a temperature of about 20 °C to about 40 °C, about 22 °C to about 30 °C in an embodiment. Quenching may be feasible for small amounts of toner such as, for example, less than about 2 liters, about 0.1 liters to about 1.5 liters in an embodiment. For larger scale processes such as, for example, those greater than about 10 liters in size, rapid cooling of the toner mixture may not be feasible or practical, whether by introducing a cooling medium into the toner mixture or by using a jacketed reactor for cooling.

[0149] Subsequently, the toner slurry can be washed. The washing can be carried out at a pH of about 7 to about 12, about 9 to about 11 in an embodiment. The washing can be carried out at a temperature of about 30 °C to about 70 °C, about 40 °C to about 67 °C in an embodiment. The washing can include filtering and re-slurrying the filter cake containing the toner particles in deionized water. The filter cake can be washed one or more times with deionized water, or washed with a single deionized water having a pH of about 4, where the pH of the slurry is adjusted with an acid and then optionally washed one or more times with deionized water.

[0150] Drying can be carried out at a temperature of about 35 °C to about 75 °C and about 45 °C to about 60 °C in an embodiment. Drying can be continued until the moisture content of the particles is below a set target of about 1 wt%, less than about 0.7 wt% in an embodiment.

[0151] The surface additive formulation described herein can be blended with the toner particles after formation. The surface additive formulation can be applied to the toner mother particles in any manner within the capabilities of those skilled in the art (including but not limited to mechanical shock and / or electrostatic attraction).

[0152] In an embodiment, the toner methods herein include: contacting at least one resin, an optional wax, an optional colorant, and an optional aggregating agent; heating to form aggregated toner particles; optionally, adding a shell resin to the aggregated toner particles and heating to a further elevated temperature to coalesce the particles; adding a surface additive comprising: at least one medium silica surface additive having an average primary particle size of 30 nanometers to 50 nanometers, the at least one medium silica provided at a surface area coverage of 40% to 100% of the surface area of the parent toner particles; at least one large silica surface additive having an average primary particle size of 80 nanometers to 120 nanometers, the at least one large silica provided at a surface area coverage of 5% to 15% of the surface area of the parent toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having an average primary particle size of 15 nanometers to 40 nanometers, present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the parent toner particles; and wherein the parent toner particles further comprise small silica having an average primary particle size of 8 nanometers to 16 nanometers, the small silica present at a surface area coverage of 5% to 75% of the surface area of the parent toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the parent toner particles; and wherein the parent toner particles further optionally comprise a small silica surface additive having a volume average primary particle size of 8 nanometers to 16 nanometers, the small silica present at a surface area coverage of 0% to 75% of the surface area of the parent toner particles; and wherein the total surface area coverage of all of the combined surface additives is 100% to 140% of the surface area of the parent toner particles; and optionally, recovering the toner particles.

[0153] In an embodiment, the toner of the present disclosure can be used as an ultra-low melt (ULM) toner. In an embodiment, dry toner particles having a core and / or shell and not containing an external surface additive can have one or more of the following characteristics:

[0154] (1) A volume average diameter (also referred to as “volume average particle size”) of from about 3 micrometers to about 25 micrometers (μm), from about 4 μm to about 15 μm in an embodiment, and from about 5 μm to about 12 μm in other embodiments.

[0155] (2) Number average geometric size distribution (GSDn) and / or volume average geometric size distribution (GSDv): In an embodiment, the toner particles described in (1) above may have a narrow size distribution with a lower numerical ratio GSD of from about 1.15 to about 1.38, and in other embodiments less than about 1.31. The toner particles of the present disclosure may also have a size such that the upper GSD is in the range of from about 1.20 to about 3.20 by volume, and in other embodiments in the range of from about 1.26 to about 3.11. The volume average particle diameter D50V, GSDv, and GSDn can be measured by means of a measuring instrument such as a Beckman Coulter Multisizer 3 operated according to the manufacturer's instructions. Representative sampling can be carried out as follows: A small amount of toner sample of about 1 gram can be obtained, filtered through a 25-micron sieve, and then placed in an isotonic solution to obtain a concentration of about 10%, and then the sample is run in a Beckman Coulter Multisizer 3.

[0156] (3) Shape factor SFl*a of from about 105 to about 170, and in an embodiment from about 110 to about 160. Scanning electron microscopy (SEM) can be used to determine the shape factor analysis of the toner by SEM and image analysis (IA). The average particle shape is quantified by using the following shape factor (SFl*a) formula:

[0157] SFl*a = 1007πd 2 / (4A),

[0158] where A is the area of the particle and d is its major axis. A perfect circular or spherical particle has a shape factor of exactly 100. The shape factor SFl*a increases as the shape becomes more irregular or elongates in a shape with a higher surface area.

[0159] (4) Roundness of from about 0.92 to about 0.99, and in other embodiments from about 0.94 to about 0.975. The instrument for measuring particle roundness, following the manufacturer's instructions, can be the FPIA-2100 manufactured by SYSMEX.

[0160] The properties of the toner particles can be determined by any suitable technique and equipment and are not limited to the instruments and techniques indicated above.

[0161] The toner particles thus formed can be formulated into a developer composition. The toner particles can be mixed with carrier particles to achieve a two-component developer composition. The toner concentration in the developer can be from about 1 wt% to about 25 wt% of the total weight of the developer, and in an embodiment from about 2 wt% to about 15 wt% of the total weight of the developer.

[0162] Examples of carrier particles that can be used in combination with toner include those particles capable of triboelectrically acquiring a charge opposite in polarity to the toner particles. Illustrative examples of suitable carrier particles include granular zirconium, granular silicon, glass, steel, nickel, ferrite, iron ferrite, silica, etc. Other carriers include those disclosed in U.S. Patent Nos. 3,847,604, 4,937,166, and 4,935,326.

[0163] The selected carrier particles can be used with or without a coating. In an embodiment, the carrier particles can include a core having a coating thereon, and the coating can be formed from a mixture of polymers not closely proximate to it in the triboelectric series. The coating can include a fluoropolymer (such as polyvinylidene fluoride resin), a terpolymer of styrene, methyl methacrylate, and / or silane (such as triethoxysilane), tetrafluoroethylene, and other known coatings. For example, a coating containing polyvinylidene fluoride (e.g., available under the trade name KYNAR 301F TM purchased) and / or polymethyl methacrylate (e.g., having a weight average molecular weight of about 300,000 to about 350,000, such as commercially available from Soken) can be used. In an embodiment, polyvinylidene fluoride and polymethyl methacrylate (PMMA) can be mixed in a ratio of about 30 wt% to about 70 wt% to about 70 wt% to about 30 wt%, and in an embodiment, about 40 wt% to about 60 wt% to about 60 wt% to about 40 wt%. The coating can have, for example, a coating weight of about 0.1 wt% to about 5 wt% of the carrier, and in an embodiment, about 0.5 wt% to about 2 wt% of the carrier.

[0164] In an embodiment, PMMA can optionally be copolymerized with any desired comonomer, provided that the resulting copolymer maintains a suitable particle size. Suitable comonomers can include monoalkylamines or dialkylamines, such as dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, diisopropylaminoethyl methacrylate, or tert-butylaminoethyl methacrylate, etc. The carrier particles can be prepared by mixing the carrier core with the polymer in an amount of about 0.05 wt% to about 10 wt%, and in an embodiment, about 0.01 wt% to about 3 wt% based on the weight of the coated carrier particles, until it adheres to the carrier core by mechanical shock and / or electrostatic attraction.

[0165] Various effective and suitable methods can be used to apply the polymer to the surface of the carrier core particles, such as cascade roll mixing, tumbling, grinding, shaking, electrostatic powder cloud spraying, fluidized bed, electrostatic disk processing, electrostatic curtain, combinations thereof, etc. Then the mixture of the carrier core particles and the polymer can be heated to melt the polymer and fix it to the carrier core particles. Then the coated carrier particles can be cooled and then classified into the desired particle size.

[0166] In an embodiment, a suitable carrier may include, for example, a steel core having a particle size of about 25 μm to about 100 μm, and in an embodiment, a particle size of about 50 μm to about 75 μm, which is coated with a conductive polymer mixture containing, for example, methacrylate and carbon black, in an amount of about 0.5 wt% to about 10 wt%, and in an embodiment, about 0.7 wt% to about 5 wt%, using the methods described in U.S. Patent Nos. 5,236,629 and 5,330,874.

[0167] The carrier particles can be mixed with the toner particles in various suitable combinations. The concentration can be about 1 wt% to about 20 wt% of the toner composition. However, different toner and carrier percentages can be used to obtain a developer composition with desired properties.

[0168] The toner can be used in electrostatographic or electrophotographic processes. In an embodiment, any known type of image development system can be used in an image development device, including, for example, magnetic brush development, jump single-component development, hybrid scavengeless development (HSD), etc. These and similar development systems are within the capabilities of those skilled in the art.

[0169] The imaging method includes, for example, preparing an image with an electrophotographic device, which includes a charging member, an imaging member, a photoconductive member, a developing member, a transfer member, and a fixing member. In an embodiment, the developing member can include a developer prepared by mixing a carrier with the toner composition described herein. The electrophotographic device can include a high-speed printer, a black-and-white high-speed printer, a color printer, etc.

[0170] Once an image is formed with the toner / developer by a suitable image development method such as any of the methods described above, the image can be transferred to an image receiving medium such as paper, etc. In an embodiment, the toner can be used to develop an image in an image development device using a fixing roller member. The fixing roller member is a contact fixing device within the capabilities of those skilled in the art, where heat and pressure from the roller can be used to fix the toner to the image receiving medium. In an embodiment, after or during melting onto the image receiving substrate, the fixing member can be heated to a temperature higher than the fixing temperature of the toner, for example, heated to a temperature of about 70°C to about 160°C, and in an embodiment, about 80°C to about 150°C, and in other embodiments, about 90°C to about 140°C.

[0171] In embodiments where the toner resin is crosslinkable, this crosslinking can be achieved in any suitable manner. For example, the toner resin can be crosslinked during toner fixing to a substrate, where the toner resin is crosslinkable at the fixing temperature. Crosslinking can also be achieved by heating the fixed image to a temperature at which the toner resin will crosslink, for example, in a post-fixing operation. In embodiments, the crosslinking can be carried out at a temperature of about 160 °C or lower, in embodiments about 70 °C to about 160 °C, and in other embodiments about 80 °C to about 140 °C.

[0172] Examples

[0173] The following examples are submitted to further define various species of the present disclosure. These examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Additionally, unless otherwise specified, all parts and percentages are by weight.

[0174] Measurement protocol.

[0175] The toner additives for Comparative Example 1, Example 1, Example 2, and Example 3 were blended as follows: 50 grams of the toner and toner surface additive as described in Table 1 were added to an SKM blender, and then blended at approximately 12,500 rpm for about 30 seconds. The black 700 Digital Color Press emulsion aggregation mother toner was used for these blends.

[0176] The mother toners for Comparative Example 2 and Examples 4 to 11 were emulsion aggregation toners with a core composed of 9 wt% of polymethylene wax having a melting point of about 90 °C, 6 wt% of 35 pigment, 1 wt% of PB15.3 pigment, 6.8 wt% of crystalline polyester resin, and the ratio of amorphous polyester resin A to amorphous polyester resin B was 85:15. The total amount of the core was 72 wt%. The shell was 28 wt% of amorphous polyester resin B. All weight percentages were calculated as a percentage of the total toner composition. The final toner particle size was 5.6 microns. Amorphous polyester resin A had an average molecular weight (Mw) of about 86,000, a number average molecular weight (Mn) of about 5,600, and an initial glass transition temperature (Tg start) of about 56 °C. Amorphous polyester resin B had an Mw of about 19,400, an Mn of about 5,000, and a Tg start of about 60 °C. The crystalline polyester resin had an Mw of about 23,300, an Mn of about 10,500, and a melting temperature (Tm) of about 71 °C. The toner blends were prepared by blending the mother black toner particles in a Piccolo blender obtained from Kawata Manufacturing Company. The total blend was 300 grams, blended at 2,260 rpm for 6.5 minutes, and mixed at 800 rpm for 4 minutes at the start.

[0177] The toner charging of the toners blended with the surface additives of Comparative Example 1, Example 1, Example 2, and Example 3 was completed through the following processes. 30 grams of 700 carrier was added with 5 pph of toner (1.5 grams) to the carrier. One sample was conditioned at 21.1 °C and 10% RH in the low humidity zone (Zone J) for three days, and another sample was conditioned at approximately 28 °C / 85% relative humidity in the high humidity zone (Zone A) for three days. The developer was loaded using a Turbula mixer for 60 minutes. The same process was used for Comparative Example 2 and Examples 4 to 11, except that 1000i carrier was used instead of 700 carrier.

[0178] The toner charge of all toners was measured as the charge / mass ratio (Q / M) by the total blow-off charge method, which measures the charge on the Faraday cage containing the developer after removing the toner by blowing in an air stream. By weighing the cage before and after the blow-off, the total charge collected in the cage was divided by the mass of the toner removed by the blow-off, thus obtaining the Q / M ratio. The toner charge was also measured in the form of Q / D (ratio of charge to diameter). Q / D was measured using a charge spectrometer with a 100 V / cm field and visually measured as the midpoint of the toner charge distribution. The charge displaced from the zero line was reported in millimeters (the mm displacement can be converted to femtocoulombs per micrometer (fC / μm) by multiplying by 0.092).

[0179] Toner adhesion measurement.

[0180] The toner adhesion of all toners was determined by measuring the toner cohesion of the toners blended with the surface additives at elevated temperatures above room temperature. The toner adhesion measurement was completed as follows: Two grams of the additive-blended toner was weighed and placed in an open dish and conditioned in an environmental chamber at the specified elevated temperature and 50% relative humidity. After 17 hours, the sample was taken out and allowed to equilibrate under environmental conditions for approximately 30 minutes. Each re-equilibrated sample was measured by sieving through a stack of two pre-weighed mesh sieves, which were stacked as follows: 1000 μm at the top and 106 μm at the bottom. The sieves were vibrated with an amplitude of approximately 1 mm for approximately 90 seconds using a Hosokawa flow tester. After the vibration was completed, the sieves were reweighed, and the toner adhesion (expressed as a percentage of the starting weight) was calculated from the total amount of toner remaining on the two sieves. Thus, for a 2-gram toner sample, if A is the weight of the toner leaving the top 1000-μm sieve and B is the weight of the toner leaving the bottom 106-μm sieve, the toner adhesion percentage is calculated by the following formula: Adhesion % = 50(A + B).

[0181] Measurement of toner flow cohesive force.

[0182] For all toners, two grams of the blended toner under laboratory environmental conditions are placed on the top sieve of a stack of three pre-weighed mesh sieves, which are stacked in a Hosokawa flow tester as follows: 53 μm at the top, 45 μm in the middle, and 38 μm at the bottom. A vibration with an amplitude of 1 mm is applied to the stack for 90 seconds. The flow cohesive force % is calculated as: Cohesive force % = (50*A + 30*B + 10*C).

[0183] Tables 1 and 2 show the surface additive compositions and the measurement results of charging, adhesion, and flow cohesive force for Comparative Example 1, Example 1, and Example 2. The SAC of each additive in the table is calculated, as well as the total SAC of all additives except the BCR and photoreceptor cleaning additives, 0.18% zinc stearate, and 0.2% strontium titanate. These cleaning additives can be ignored in the following discussion of the examples because they can vary independently for cleaning without significantly affecting the charge, adhesion, and flow properties.

[0184] All additive combinations in Table 1 have less than 1% titanium dioxide, as preferred. All combinations have the first medium silica, the second medium silica, and the large silica. Comparative Example 1 does not have the small silica with a total SAC = 108, which results in a high weight % additive loading of 5.8 wt%. Since the additive cost is by weight, this additive combination is expensive. However, for good adhesion and aging performance in printers, it is desirable for the SAC to remain relatively high, ideally at least 100%.

[0185] Example 1 reduced the amount of medium silica and increased the amount of small-sized silica, resulting in the same SAC as Comparative Example 1 but with only a total loading of 4.4 wt% of silica and titanium dioxide. Since the additive cost is by weight, this additive package is much cheaper but provides the same performance. Toner Example 2 has a higher SAC but less of the large silica X24. Generally, colloidal silica is more expensive than small-sized and medium-sized silica, so even though we increased the SAC, this is a cheaper additive combination. In this design, it was demonstrated that using the same additives could reduce the X24 loading / cost by 2X, and since this is the most expensive additive, this additive combination is even cheaper. The total loading is 4.1 wt%, even lower than Comparative Example 1, and slightly lower than Example 2. The higher SAC provides some additional aging performance benefits in printing and also has improved flowability due to the reduction of large silica and the increase of small silica. Toner Example 3 is the same as Toner Example 1, except that titanium dioxide has been completely replaced by alumina C805. Toner Example 3 is similar to Toner Comparative Example 1, except that titanium dioxide has been completely replaced by alumina and the amount of small silica has been increased. The result is that Toner Example 3 has a much lower additive loading compared to Comparative Example 1, but a similar SAC provides good aging performance and has a similar charge and relative humidity sensitivity of charge between Zone A and Zone J. The blocking temperature is about 1 °C lower than Comparative Example 1 but is still very good. And Toner Example 3 has the advantage of completely removing titanium dioxide.

[0186] Table 1

[0187]

[0188]

[0189] Table 2

[0190]

[0191] The toners in Table 3, Table 4, Table 5, and Table 6 do not contain any small silica. In Table 3, Table 4, Table 5, and Table 6, all toners have similar additive loadings and also have similar costs for the additive formulations. Comparative Example 2 contains a titanium dioxide surface additive, while all the Examples have C805 alumina replacing titanium dioxide and thus do not contain titanium dioxide. All the Examples have a higher charge than Comparative Example 2. When X24-9163A is used with a higher amount of alumina in Example 4, the charge is lower, while when C191 is used with a lower amount of alumina, the charge is the highest. In these formulations, alumina and large silica can be used to control the charge level. In an embodiment, it is useful to provide a higher charge, for example, when the parent charge is low. If a lower charge is needed, more X24-9163A or alumina can be added. In all the Examples, it is advantageous that the RH sensitivity ratio of the charge is higher and better than that of Comparative Example 2. In all the Examples, the blocking temperature is increased by at least 2 °C. The toner cohesion is similar in all the Examples, slightly worse in some Examples, and slightly improved in Example 4.

[0192] Table 3

[0193]

[0194] Table 4

[0195]

[0196] As shown in Table 3, the Examples in Table 5 do not contain any small silica and have all replaced titanium dioxide with alumina and thus do not contain titanium dioxide. In Table 5, all toners have an increased additive loading weight %, and thus are more expensive. All toners also have increased and similar SAC to provide similar additive coverage of the toner for aging performance. In these Example formulations, all formulations have a higher charge than Comparative Example 2, but the charge levels are reasonably close to Comparative Example 2. Compared with Comparative Example 2, all toner Examples in Table 5 have a better and higher ratio of A zone charge to J zone charge and have further improved blocking compared to the toner Examples and Comparative Example 2 in Table 3. The toner cohesion of the Examples in Table 5 is in the range from lower than to higher than that of Comparative Example 2.

[0197] Table 5

[0198]

[0199]

[0200] Table 6

[0201]

[0202] It should be understood that various ones or alternatives of the above-disclosed features and functions can be desirably combined into many other different systems or applications. It should also be understood that those skilled in the art may subsequently make various substitutions, modifications, variations or improvements that are currently unforeseen or unanticipated, and these are also intended to be covered by the appended claims. Unless specifically recited in the claims, the steps or components of the claims should not imply or import from the specification or any other claims any particular order, quantity, position, size, shape, angle, color or material.

Claims

1. A toner, the toner comprising: Mother toner particles, the mother toner particles comprising at least one resin combined with an optional colorant, and an optional wax, wherein the at least one resin of the mother toner particles comprises a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester, and a crystalline polyester; and A surface additive formulation, the surface additive formulation comprising: At least one medium silica surface additive having a volume average primary particle size of 30 nm to 50 nm, the at least one medium silica provided at a surface area coverage rate of 40% to 100% of the surface area of the mother toner particles; At least one large silica surface additive having a volume average primary particle size of 80 nm to 120 nm, the at least one large silica provided at a surface area coverage rate of 5% to 29% of the surface area of the mother toner particles; At least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) A titanium dioxide surface additive having a volume average primary particle size of 15 nm to 40 nm, the titanium dioxide present in an amount of less than or equal to 1 part per hundred parts based on 100 parts of the mother toner particles; and wherein the mother toner particles further comprise small silica having a volume average primary particle size of 8 nm to 16 nm, the small silica present at a surface area coverage rate of 5% to 75% of the surface area of the mother toner particles; or (b) A positively charged non-titanium dioxide metal oxide surface additive, wherein the toner surface additive formulation does not contain titanium dioxide, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nm to 30 nm, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage rate of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further optionally comprise small silica surface additive having a volume average primary particle size of 8 nm to 16 nm, the small silica present at a surface area coverage rate of 0% to 75% of the surface area of the mother toner particles; Wherein the total surface area coverage rate of all the combined surface additives is 100% to 140% of the surface area of the mother toner particles, Wherein the surface area coverage rate SAC percentage of the additive relative to the mother toner particles can be calculated as: SAC = 100●(w●D●P) / (0.363●d●p) Among them, For toner mother particles, D is the D50 volume average size in microns, and P is the true packing density in g / cm 3 3; and wherein, for toner surface additives, d is the D50 volume average particle size in nanometers, p is the true packing density in g / cm 3 3, and w is the weight of the toner surface additive added to the mixture in parts per hundred parts based on the toner mother particles.

2. The toner according to claim 1, wherein the at least one medium silica comprises two or more medium silicas, and wherein the two or more medium silicas include surface-treated medium silicas selected from the group consisting of: silica treated with an alkylsilane, silica treated with polydimethylsiloxane, and combinations thereof.

3. The toner according to claim 1, wherein the at least one medium silica includes a first medium silica and a second medium silica, the first medium silica is silica treated with an alkylsilane, and the second medium silica is silica treated with polydimethylsiloxane.

4. The toner according to claim 1, wherein the positively charged non-titanium dioxide metal oxide surface additive is selected from the group consisting of alumina, strontium titanate, alumina treated with an alkylsilane, alumina treated with polydimethylsiloxane, and combinations thereof.

5. The toner according to claim 1, wherein the positively charged non-titanium dioxide metal oxide surface additive is alumina.

6. The toner according to claim 1, wherein the positively charged non-titanium dioxide metal oxide surface additive is selected from the group consisting of metal oxides, and the metal oxides include at least one member selected from the group consisting of Bronsted bases, Lewis bases, and amphoteric compounds.

7. The toner according to claim 1, wherein the positively charged non-titanium dioxide metal oxide surface additive is silica treated with a basic or amphoteric surface treating agent.

8. The toner according to claim 1, wherein the small silica is selected from the group consisting of silica treated with an alkylsilane, silica treated with polydimethylsiloxane, and combinations thereof.

9. The toner according to claim 1, wherein the at least one resin of the mother toner particles is selected from the group consisting of styrene, acrylate, methacrylate, butadiene, isoprene, acrylic acid, methacrylic acid, acrylonitrile, copolymers thereof, and combinations thereof.

10. The toner according to claim 1, wherein the toner includes a core-shell configuration; wherein the core includes at least one amorphous polyester and at least one crystalline polyester; and wherein the shell includes at least one amorphous polyester.

11. The toner according to claim 1, wherein the toner includes a core-shell configuration; wherein the core includes at least one amorphous polyester and at least one crystalline polyester; and wherein the shell includes a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester.

12. The toner according to claim 1, wherein the colorant is selected from cyan colorants, magenta colorants, yellow colorants, black colorants, or combinations thereof.

13. The toner according to claim 1, wherein the at least one positively charged surface additive is (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the toner surface additive formulation does not contain titanium dioxide, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the mother toner particles; and The mother toner particles also optionally contain small silica surface additives having a volume average primary particle size of 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage rate of 0% to 75% of the surface area of the mother toner particles.

14. A toner method, the toner method comprising: contacting at least one resin, an optional wax, an optional colorant, and an optional aggregating agent, wherein the at least one resin comprises a first amorphous polyester and a second amorphous polyester different from the first amorphous polyester, and a crystalline polyester; heating to form aggregated toner particles; optionally, adding a shell resin to the aggregated toner particles and heating to a further elevated temperature to coalesce the particles; adding surface additives, the surface additives comprising: at least one medium silica surface additive having a volume average primary particle size of 30 nanometers to 50 nanometers, the at least one medium silica being provided at a surface area coverage rate of 40% to 100% of the surface area of the mother toner particles; at least one large silica surface additive having a volume average primary particle size of 80 nanometers to 120 nanometers, the at least one large silica being provided at a surface area coverage rate of 5% to 29% of the surface area of the mother toner particles; at least one positively charged surface additive, wherein the at least one positively charged surface additive is: (a) a titanium dioxide surface additive having a volume average primary particle size of 15 nanometers to 40 nanometers, and based on 100 parts of the mother toner particles, the titanium dioxide is present in an amount of less than or equal to 1 part per 100 parts; and wherein the mother toner particles further contain small silica having a volume average primary particle size of 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage rate of 5% to 75% of the surface area of the mother toner particles; or (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the toner surface additive formulation does not contain titanium dioxide, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage rate of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles also optionally contain small silica surface additives having a volume average primary particle size of 8 nanometers to 16 nanometers, and the small silica is present at a surface area coverage rate of 0% to 75% of the surface area of the mother toner particles; wherein the total surface area coverage rate of all the combined surface additives is 100% to 140% of the surface area of the mother toner particles; and optionally, recovering the toner particles, wherein the surface area coverage rate SAC percentage of the additive relative to the toner mother particles can be calculated as: SAC = 100●(w●D●P) / (0.363●d●p) Wherein, for the toner mother particles, D is the D50 volume average size in microns, and P is the true bulk density in g / cm 3 3; and wherein, for the toner surface additive, d is the D50 volume average particle size in nanometers, p is the true bulk density in g / cm 3 3, and w is the weight of the toner surface additive added to the mixture in parts per hundred parts based on the toner mother particles.

15. The toner method according to claim 14, wherein the at least one medium silica comprises two or more medium silicas, and wherein the two or more medium silicas comprise surface-treated medium silicas selected from the group consisting of silica treated with an alkylsilane, silica treated with polydimethylsiloxane, and combinations thereof.

16. The toner method according to claim 14, wherein the at least one medium silica comprises a first medium silica and a second medium silica, the first medium silica being silica treated with an alkylsilane and the second medium silica being silica treated with polydimethylsiloxane.

17. The toner method according to claim 14, wherein the positively charged non-titanium dioxide metal oxide surface additive is selected from the group consisting of alumina, strontium titanate, and combinations thereof.

18. The toner method according to claim 14, wherein the at least one resin of the mother toner particles is selected from the group consisting of styrene, acrylate, methacrylate, butadiene, isoprene, acrylic acid, methacrylic acid, acrylonitrile, copolymers thereof, and combinations thereof.

19. The toner method according to claim 14, wherein the at least one positively charged surface additive is (b) a positively charged non-titanium dioxide metal oxide surface additive, wherein the toner surface additive formulation does not contain titanium dioxide, wherein the positively charged non-titanium dioxide metal oxide surface additive has a volume-average primary particle size of 8 nanometers to 30 nanometers, and wherein the positively charged non-titanium dioxide metal oxide surface additive is present at a surface area coverage of 5% to 15% of the surface area of the mother toner particles; and wherein the mother toner particles further optionally comprise small silica surface additives having a volume-average primary particle size of 8 nanometers to 16 nanometers, the small silica being present at a surface area coverage of 0% to 75% of the surface area of the mother toner particles.

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