# Patent

## Title
Bio-based polyester resins

## Abstract

A polyester resin is described which includes bio-based, cyclohexadiene Diels-Alder reaction adduct monomer for use in toner for imaging devices.

## Background
FIELD
Polyester resins comprising a Diels-Adler adduct-containing monomer for making toner, where the adduct is bio-based; developers comprising said toner particles; devices comprising said toner particles and developers; imaging device components comprising said toner particles and developers; imaging devices comprising said developers; and so on, are described.
BACKGROUND
Emulsion aggregation (EA) toner particles may comprise a polyester resin. The polyester resin may be produced from monomers derived from renewable resources. However, the range of bio-based, commercially available diols and diacids is limited, and the available chemical structures are mostly small, aliphatic, linear molecules with low carbon-oxygen ratios. When used to prepare polyesters for toner, such diacids and diesters yield toner with low glass transition temperature (Tg) and high equilibrium moisture content, which adversely affect charging and fusing properties of the resulting toners. Petroleum-based monomers, such as, terephthalic acid (TA), naphthalene dicarboxylic acid (NDC) and cyclohexene dicarboxylic acid (CHDA) are thus often included in resin formulations. While not, “green,” those monomers are hydrophobic (high carbon-oxygen ratio) and structurally rigid, bringing charge and fusing properties close to existing polyester toner specifications.
There remains a need for bio-based monomers that share those advantageous physico-chemical properties.
SUMMARY
The instant disclosure provides a polyester resin which includes a bio-based, cyclohexadiene Diels-Alder reaction adduct that may be used in manufacturing toner for imaging devices. In embodiments, the adduct may be included in a polymerization reaction or added as a pre-polymer or macromer which may be further reacted with other monomers to obtain higher molecular weight resins with high C/O ratios.
In embodiments, a toner composition is disclosed including a resin containing a first monomer comprising a Diels-Alder reaction adduct, where the diene includes a substituted cyclohexadiene component of an essential oil, where the dienophile comprises maleic acid, maleic anhydride or fumaric acid, and where the resulting adduct is a bicyclic compound having a six-membered ring; an optional colorant; and an optional wax.
In embodiments, a toner composition is disclosed including a resin containing first monomer and at least one second monomer, where the first monomer comprises a Diels-Alder reaction adduct of 1-methyl-4-(propan-2-yl)cyclohexa-1,3-diene (α-terpinene) or 2-methyl-5-(propan-2-yl)cyclohexa-1,3-diene (α-phellandrene) and where the dienophile comprises maleic acid, maleic anhydride or fumaric acid; an optional colorant; and an optional wax.
In embodiments, a toner composition is disclosed containing a resin comprising monomers of Diels-Alder reaction adducts of 1-methyl-4-(propan-2-yl)cyclohexa-1,3-diene (α-terpinene) or 2-methyl-5-(propan-2-yl)cyclohexa-1,3-diene (α-phellandrene), where the dienophile comprises a dicarboxylic acid or cyclic anhydride; an optional colorant; and an optional wax.


DETAILED DESCRIPTION
I. Introduction
The present disclosure describes the use of Diels-Alder adducts of essential oil components, including but not limited to, α-terpinene, α-phellandrene, β-damascenone, 2,6,6-trimethyl-1,3-cyclohexadiene-1-carboxylate, sedanenolide β-butyl-4,5-dihydrophthalide), zingiberene, ligustilide and α-terpine-7-al as monomers for toner resins. For example, both terpinene and phellandrene are natural fragrance and flavoring ingredients isolated from natural essential oils, which also can be prepared from pinene or limonene, respectively. Both have rigid ring cyclohexadiene structures that are suitable for Diels-Alder reactions with maleic or fumaric acids (or equivalents thereof). The resulting diacids or dianhydrides are suitable as terephthalic acid, cyclohexane dicarboxylic acid or naphthalene dicarboxylic acid substitutes.
The oil components of interest react with, for example, maleic anhydride to form bicyclic structures with a cis-diacid type orientation, although trans-diacid orientations may be achieved by replacing maleic anhydride with, for example, fumaric acid esters. Either form may be introduced into a polyester-forming reaction as a dicarboxylic acid, an anhydride or a diester.




Only single enantiomers are depicted above to show relative stereochemistry. However, the reaction produces equal quantities of each enantiomer (including diestereomers in the case of phellandrene). The monomers as disclosed are approximately 65% bio-based (the maleic anhydride and fumaric acid may be obtained from non-biomass sources).
For the purposes of the instant disclosure, the term, “essential oil,” refers to a concentrated hydrophobic liquid containing volatile aromatic compounds from a plant cell, a microbe or an animal cell, or may be made synthetically based thereon.
Unless otherwise indicated, all numbers expressing quantities and conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term, “about.” “About,” is meant to indicate a variation of no more than 20% from the stated value. Also used herein is the term, “equivalent,” “similar,” “essentially,” “substantially,” “approximating” and “matching,” or grammatical variations thereof, have generally acceptable definitions or at the least, are understood to have the same meaning as, “about.”
As used herein, “bio-based” means a commercial or industrial product (other than food or feed) that is composed, in whole or in substantial part (e.g., at least about 20%, at least about 30%, at least about 40% or more, up to about 99% by weight of the resin), of biological products or renewable domestic agricultural materials (including plant, animal, and marine materials) or forestry materials. Generally, a bio-based material is biodegradable, that is, substantially or completely biodegradable, by substantially is meant greater than 50%, greater than 60%, greater than 70% or more of the material is degraded from the original molecule to another form by a biological or environmental means, such as, action thereon by bacteria, animals, plants and so on in a matter of days, matter of weeks, a year or more.
As disclosed herein, the Diels-Alder reaction is facilitated by electron-donating groups on a diene (e.g., α-terpinene) and electron attracting groups on a monoene, such as maleic anhydride (i.e., “dienophile”), to form a Diels-Alder adduct.
II. Toner Particles
Toner particles of interest comprise a polyester resin made using a bio-based, cyclohexadiene Diels-Alder reaction adduct (DA-adduct). Thus, a resin-forming monomer and a bio-based DA-adduct are reacted with suitable other reactants to form a polymer.
The resin comprises a polyester polymer, and in the context of a toner for use with certain imaging devices, comprises a polyester polymer that solidifies to form a particle. A composition may comprise more than one form or sort of polymer, such as, two or more different polymers, such as, two or more different polyester polymers composed of different monomers. The polymer may be an alternating copolymer, a block copolymer, a graft copolymer and so on.
The toner particle may include other optional reagents, such as, a surfactant, a wax, a shell and so on. The toner composition optionally may comprise inert particles, which may serve as toner particle carriers, which may comprise a resin taught herein. The inert particles may be modified, for example, to serve a particular function. Hence, the surface thereof may be derivatized or the particles may be manufactured for a desired purpose, for example, to carry a charge or to possess a magnetic field.
A. Components
1. Resin
Toner particles of the instant disclosure include a resin-forming monomer suitable for use in forming a particulate containing or carrying a colorant of a toner for use in certain imaging devices. Any polyfunctional monomer may be used depending on the particular polyester polymer desired in a toner particle. Hence, bifunctional reagents, trifunctional reagents and so on may be used. Examples of such polyfunctional monomers include 1,2,4-benzene-tricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylene-carboxylpropane, tetra(methylene-carboxyl)methane and 1,2,7,8-octanetetracarboxylic acid.
One, two or more polymers may be used in forming a toner or toner particle. In embodiments, where two or more polymers are used, the polymers may be in any suitable ratio (e.g., weight ratio) such as, for instance, with two different polymers, from about 1% (first polymer)/99% (second polymer) to about 99% (first polymer)/1% (second polymer), from about 10% (first polymer)/90% (second polymer) to about 90% (first polymer)/10% (second polymer) and so on, as a design choice.
The resin may be present in an amount of from about 65 to about 95% by weight, from about 75 to about 85% by weight of toner particles on a solids basis.
a. Polyester Resins
Suitable polyester resins include, for example, those which are sulfonated, non-sulfonated, crystalline, amorphous, combinations thereof and the like. Polyester resins may include those described, for example, in U.S. Pat. Nos. 6,593,049; 6,830,860; 7,754,406; 7,781,138; 7,749,672; and 6,756,176, the disclosure of each of which hereby is incorporated by reference in entirety.
When a mixture is used, such as, amorphous and crystalline polyester resins, the ratio of crystalline polyester resin to amorphous polyester resin may be in the range from about 1:99 to about 30:70; from about 5:95 to about 25:75; from about 5:95 to about 15:95.
A polyester resin may be obtained synthetically, for example, in an esterification reaction involving a reagent comprising dicarboxylic acid groups and another reagent comprising a dialcohols or diol. In embodiments, the alcohol reagent comprises two or more hydroxyl groups, three or more hydroxyl groups. In embodiments, the acid comprises two or more carboxylic acid groups, three or more carboxylic acid groups. Reagents comprising three or more functional groups enable, promote or enable and promote polymer branching and crosslinking. In embodiments, a polymer backbone or a polymer branch comprises at least one monomer unit comprising at least one pendant group or side group, that is, the monomer reactant from which the unit was obtained comprises at least three functional groups.
Examples of polyacids or polyesters that may be used for preparing an amorphous polyester resin include terephthalic acid, phthalic acid, isophthalic acid, fumaric acid, trimellitic acid, diethyl fumarate, dimethyl itaconate, cis-1,4-diacetoxy-2-butene, dimethyl fumarate, diethyl maleate, maleic acid, succinic acid, itaconic acid, succinic acid, cyclohexanoic acid, succinic anhydride, dodecylsuccinic acid, dodecylsuccinic anhydride, glutaric acid, glutaric anhydride, adipic acid, pimelic acid, suberic acid, azelaic acid, dodecanedioic acid, dimethyl naphthalenedicarboxylate, dimethyl terephthalate, diethyl terephthalate, dimethylisophthalate, diethylisophthalate, dimethylphthalate, phthalic anhydride, diethylphthalate, dimethylsuccinate, naphthalene dicarboxylic acid, dimer diacid, dimethylfumarate, dimethylmaleate, dimethylglutarate, dimethyladipate, dimethyl dodecylsuccinate and combinations thereof. The polyacid or polyester reagent may be present, for example, in an amount from about 40 to about 60 mole % of the resin, from about 42 to about 52 mole % of the resin, from about 45 to about 50 mole % of the resin, and optionally a second polyacid may be used in an amount from about 0.1 to about 10 mole % of the resin.
Examples of polyols which may be used in generating an amorphous polyester resin 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, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, xylenedimethanol, cyclohexanediol, diethylene glycol, bis(2-hydroxyethyl) oxide, dipropylene glycol, bis(hydroxyalkyl) bisphenol A, hydrogenated bisphenol A, dibutylene glycol and combinations thereof. The amount of polyol may vary, and may be present, for example, in an amount from about 40 to about 60 mole % of the resin, from about 42 to about 55 mole % of the resin, from about 45 to about 53 mole % of the resin.
Polycondensation catalysts may be used in forming the amorphous (or crystalline) polyester resin, and include tetraalkyl titanates, dialkyltin oxides, such as, dibutyltin oxide, tetraalkyltins, such as, dibutyltin dilaurate, and dialkyltin oxide hydroxides, such as, butyltin oxide hydroxide, aluminum alkoxides, alkyl zinc, dialkyl zinc, zinc oxide, stannous oxide, or combinations thereof. Such catalysts may be used in amounts of, for example, from about 0.01 mole % to about 5 mole % based on the starting polyacid or polyester reagent(s) used to generate the polyester resin.
Examples of amorphous resins which may be used include alkali sulfonated-polyester resins, branched alkali sulfonated-polyester resins, alkali sulfonated-polyimide resins and branched alkali sulfonated-polyimide resins. Alkali sulfonated polyester resins may be useful in embodiments, such as, the metal or alkali salts of copoly(ethylene-terephthalate)-copoly(ethylene-5-sulfo-isophthalate), copoly(propylene-terephthalate)-copoly(propylene-5-sulfo-isophthalate), copoly(diethylene-terephthalate)-copoly(diethylene-5-sulfo-isophthalate), copoly(propylene-diethylene-terephthalate)-copoly(propylene-diethylene-5-sulfoisophthalate), copoly(propylene-butylene-terephthalate)-copoly(propylene-butylene-5-sulfo-isophthalate), copoly(propoxylated bisphenol-A-fumarate)-copoly(propoxylated bisphenol A-5-sulfo-isophthalate), copoly(ethoxylated bisphenol-A-fumarate)-copoly(ethoxylated bisphenol-A-5-sulfo-isophthalate) and copoly(ethoxylated bisphenol-A-maleate)-copoly(ethoxylated bisphenol-A-5-sulfo-isophthalate), wherein the alkali metal is, for example, a sodium, a lithium or a potassium ion.
In embodiments, an unsaturated amorphous polyester resin may be used as a latex resin. Examples of such resins include those disclosed in U.S. Pat. No. 6,063,827, the disclosure of which herein is incorporated by reference in entirety. Exemplary unsaturated amorphous polyester resins include, but are not limited to, poly(propoxylated bisphenol co-fumarate), poly(ethoxylated bisphenol co-fumarate), poly(butyloxylated bisphenol co-fumarate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol co-fumarate), poly(1,2-propylene fumarate), poly(propoxylated bisphenol co-maleate), poly(ethoxylated bisphenol co-maleate), poly(butyloxylated bisphenol co-maleate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol co-maleate), poly(1,2-propylene maleate), poly(propoxylated bisphenol co-itaconate), poly(ethoxylated bisphenol co-itaconate), poly(butyloxylated bisphenol co-itaconate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol co-itaconate), poly(1,2-propylene itaconate) and combinations thereof.
For forming a crystalline polyester resin, suitable organic polyols include aliphatic polyols with 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 and the like; alkali sulfo-aliphatic diols such as sodio 2-sulfo-1,2-ethanediol, lithio 2-sulfo-1,2-ethanediol, potassio 2-sulfo-1,2-ethanediol, sodio 2-sulfo-1,3-propanediol, lithio 2-sulfo-1,3-propanediol, potassio 2-sulfo-1,3-propanediol, mixture thereof and the like, including structural isomers thereof. The aliphatic polyol may be, for example, selected in an amount from about 40 to about 60 mole %, from about 42 to about 55 mole %, from about 45 to about 53 mole % of the resin.
Examples of polyacid or polyester reagents for preparing a crystalline resin include oxalic acid, succinic acid, glutaric acid, adipic acid, dodecanedioic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, dimethyl fumarate, dimethyl itaconate, cis-1,4-diacetoxy-2-butene, diethyl maleate, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, cyclohexane dicarboxylic acid (sometimes referred to herein, in embodiments, as cyclohexanedioic acid), malonic acid and mesaconic acid, a polyester or anhydride thereof; and an alkali sulfo-organic polyacid, such as, the sodio, lithio or potassio salt of dimethyl-5-sulfo-isophthalate, dialkyl-5-sulfo-isophthalate-4-sulfo-1,8-naphthalic anhydride, 4-sulfo-phthalic acid, dimethyl-4-sulfo-phthalate, dialkyl-4-sulfo-phthalate, 4-sulfophenyl-3,5-dicarbomethoxybenzene, 6-sulfo-2-naphthyl-3,5-dicarbomethoxybenzene, sulfo-terephthalic acid, dimethyl-sulfo-terephthalate, 5-sulfo-isophthalic acid, dialkyl-sulfo-terephthalate, sulfo-p-hydroxybenzoic acid, N,N-bis(2-hydroxyethyl)-2-amino ethane sulfonate or mixtures thereof. The polyacid may be selected in an amount of, for example, from about 40 to about 60 mole %, from about 42 to about 52 mole %, from about 45 to about 50 mole %, and optionally, a second polyacid may be selected in an amount from about 0.1 to about 10 mole % of the resin.
Specific crystalline resins include poly(ethylene-adipate), poly(propylene-adipate), poly(butylene-adipate), poly(pentylene-adipate), poly(hexylene-adipate), poly(octylene-adipate), poly(ethylene-succinate), poly(propylene-succinate), poly(butylene-succinate), poly(pentylene-succinate), poly(hexylene-succinate), poly(octylene-succinate), poly(ethylene-sebacate), poly(propylene-sebacate), poly(butylene-sebacate), poly(pentylene-sebacate), poly(hexylene-sebacate), poly(octylene-sebacate), poly(decylene-sebacate), poly(decylene-decanoate), poly(ethylene-decanoate), poly(ethylene dodecanoate), poly(nonylene-sebacate), poly(nonylene-decanoate), copoly(ethylene-fumarate)-copoly(ethylene-sebacate), copoly(ethylene-fumarate)-copoly(ethylene-decanoate), copoly(ethylene-fumarate)-copoly(ethylene-dodecanoate), copoly(2,2-dimethylpropane-1,3-diol-decanoate)-copoly(ethylene-adipate), alkali copoly(5-sulfoisophthaloyl)-copoly(propylene-adipate), alkali copoly(5-sulfoisophthaloyl)-copoly(butylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(pentylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(hexylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(octylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(ethylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(propylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(butylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(pentylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(hexylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(octylene-adipate), alkali copoly(5-sulfoisophthaloyl)-copoly(ethylene-succinate), alkali copoly(5-sulfoisophthaloyl)-copoly(propylene-succinate), alkali copoly(5-sulfoisophthaloyl)-copoly(butylenes-succinate), alkali copoly(5-sulfoisophthaloyl)-copoly(pentylene-succinate), alkali copoly(5-sulfoisophthaloyl)-copoly(hexylene-succinate), alkali copoly(5-sulfoisophthaloyl)-copoly(octylene-succinate), alkali copoly(5-sulfo-isophthaloyl)-copoly(ethylene-sebacate), alkali copoly(5-sulfo-isophthaloyl)-copoly(propylene-sebacate), alkali copoly(5-sulfo-isophthaloyl)-copoly(butylene-sebacate), alkali copoly(5-sulfo-isophthaloyl)-copoly(pentylene-sebacate), alkali copoly(5-sulfo-isophthaloyl)-copoly(hexylene-sebacate), alkali copoly(5-sulfo-isophthaloyl)-copoly(octylene-sebacate), alkali copoly(5-sulfo-isophthaloyl)-copoly(ethylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(propylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(butylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(pentylene-adipate), alkali copoly(5-sulfo-isophthaloyl)-copoly(hexylene-adipatenonylene-decanoate), poly(octylene-adipate) and so on, wherein alkali is a metal like sodium, lithium or potassium. Examples of polyamides include poly(ethylene-adipamide), poly(propylene-adipamide), poly(butylenes-adipamide), poly(pentylene-adipamide), poly(hexylene-adipamide), poly(octylene-adipamide), poly(ethylene-succinimide), and poly(propylene-sebecamide). Examples of polyimides include poly(ethylene-adipimide), poly(propylene-adipimide), poly(butylene-adipimide), poly(pentylene-adipimide), poly(hexylene-adipimide), poly(octylene-adipimide), poly(ethylene-succinimide), poly(propylene-succinimide) and poly(butylene-succinimide).
Suitable crystalline resins which may be utilized, optionally in combination with an amorphous resin as described above, include those disclosed in U.S. Pub. No. 2006/0222991, the disclosure of which is hereby incorporated by reference in entirety.
Examples of other suitable resins or polymers which may be utilized in forming a toner include, but are not limited to, 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), polystyrene-butadiene-acrylic acid), poly(styrene-butadiene-methacrylic acid), polystyrene-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), and combinations thereof. The polymer may be, for example, block, random or alternating copolymers.
The crystalline resin may be present, for example, in an amount from about 1 to about 85% by weight of the toner components, from about 2 to about 50% by weight of the toner components, from about 5 to about 15% by weight of the toner components. The crystalline resin may possess melting points of, for example, from about 30° C. to about 120° C., from about 50° C. to about 90° C., from about 60° C. to about 80° C. The crystalline resin may have a number average molecular weight (Mn), as 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, and a weight average molecular weight (Mw) of, for example, from about 2,000 to about 100,000, from about 3,000 to about 80,000, as determined by GPC using polystyrene standards. The molecular weight distribution (Mw/Mn) of the crystalline resin may be, for example, from about 2 to about 6, from about 3 to about 4.
b. Bio-Based, Diels-Adler Adduct-Containing Monomer
A monomer comprising a Diels-Alder reaction adduct, where the diene comprises a substituted cyclohexadiene component of an essential oil, may be used as a monomer for a synthesis reaction. In embodiments, adduct-containing monomers may be added as pre-polymers or macromers that may be further reacted with other monomers to obtain high molecular weight resins.
Suitable adducts are those that may be introduced into a polyester-forming reaction as either a dicarboxylic acid, an anhydride or a diester. Examples include, α-terpinene, α-phellandrene, β-damascenone, 2,6,6-trimethyl-1,3-cyclohexadiene-1-carboxylate, sedanenolide (3-butyl-4,5-dihydrophthalide), zingiberene, ligustilide, α-terpine-7-al, combinations thereof and the like. Those compounds may be obtained from natural sources, practicing known methods (see, e.g., Common Fragrance and Flavoring Materials: Preparation and Uses, (2001), 4th ed., Bauer et al. (eds.), Wiley-VCH, Verlag GmbH, New York, N.Y., herein incorporated by reference in entirety).
The adduct may be used to make a resin in an amount of from about 0.05 to about 0.5 mol eq., from about 0.5 to about 0.25 mol eq., from about 0.25 to about 0.50 mol eq. of a polyester-forming reaction mixture in known reaction schemes.
c. Catalyst
Condensation catalysts which may be used in the polyester reaction include tetraalkyl titanates; dialkyltin oxides, such as, dibutyltin oxide; tetraalkyltins, such as, dibutyltin dilaurate; dibutyltin diacetate; dibutyltin oxide; dialkyltin oxide hydroxides, such as, butyltin oxide hydroxide; aluminum alkoxides, alkyl zinc, dialkyl zinc, zinc oxide, stannous oxide, stannous chloride, butylstannoic acid, or combinations thereof.
Such catalysts may be used in amounts of, for example, from about 0.01 mole % to about 5 mole % based on the amount of starting polyacid, polyol or polyester reagent in the reaction mixture.
Generally, as known in the art, the polyacid/polyester are mixed together, optionally with a catalyst, and incubated at an elevated temperature, such as, from about 180° C. or more, from about 190° C. or more, from about 200° C. or more, and so on, which may be conducted anaerobically, to enable esterification to occur until equilibrium, which generally yields water or an alcohol, such as, methanol, arising from forming the ester bonds in the esterification reaction. The reaction may be conducted under vacuum to promote polymerization. The product is collected by known methods, and may be dried, again, by known methods to yield particulates.
Polyester resins of the present disclosure are those which carry one or more properties, such as a Tg(onset) of from about 20° C. to about 90° C., from about 25° C. to about 85° C., from about 30° C. to about 80° C.; a Ts of from about 80° C. to about 100° C., from about 85° C. to about 125° C., from about 90° C. to about 120° C.; an acid value (AV) of from about 3 to about 70, from about 4 to about 65, from about 5 to about 60; an Mn of from about 500 to about 20000, from about 750 to about 15000, from about 1000 to about 10000; and an Mw of from about 1000 to about 100000, from about 2000 to about 75000, from about 3000 to about 50000.
2. Colorants
Suitable colorants include those comprising carbon black, such as, REGAL 330® and Nipex 35; magnetites, such as, Mobay magnetites, MO8029TM and MO8060TM; Columbian magnetites, MAPICO® BLACK; surface-treated magnetites; Pfizer magnetites, CB4799TM, CB5300TM, CB5600TM and MCX6369TM; Bayer magnetites, BAYFERROX 8600TM and 8610TM; Northern Pigments magnetites, NP604TM and NP608TM; Magnox magnetites, TMB-100TM or TMB-104TM; and the like.
Colored pigments, such as, cyan, magenta, yellow, red, orange, green, brown, blue or mixtures thereof may be used. The additional pigment or pigments may be used as water-based pigment dispersions.
Examples of pigments include SUNSPERSE 6000, FLEXIVERSE and AQUATONE, water-based pigment dispersions from SUN Chemicals; HELIOGEN BLUE L6900TM, D6840TM, D7080TM, D7020TM, PYLAM OIL BLUETM, PYLAM OIL YELLOWTM and PIGMENT BLUE ITM available from Paul Uhlich & Company, Inc.; PIGMENT VIOLET ITM, PIGMENT RED 48TM, LEMON CHROME YELLOW DCC lO26TM, TOLUIDINE REDTM and BON RED CTM available from Dominion Color Corporation, Ltd., Toronto, Ontario; NOVAPERM YELLOW FGLTM and HOSTAPERM PINK ETM from Hoechst; CINQUASIA MAGENTATM available from E.I. DuPont de Nemours & Co. and the like.
Examples of magenta pigments include 2,9-dimethyl-substituted quinacridone, an anthraquinone dye identified in the Color Index as CI 60710, CI Dispersed Red 15, a diazo dye identified in the Color Index as CI 26050, CI Solvent Red 19 and the like.
Illustrative examples of cyan pigments include copper tetra(octadecylsulfonamido) phthalocyanine, a copper phthalocyanine pigment listed in the Color Index as CI 74160, CI Pigment Blue, Pigment Blue 15:3, Pigment Blue 15:4, an Anthrazine Blue identified in the Color Index as CI 69810, Special Blue X-2137 and the like.
Illustrative examples of yellow pigments are diarylide yellow 3,3-dichlorobenzidene acetoacetanilide, a monoazo pigment identified in the Color Index as CI 12700, CI Solvent Yellow 16, a nitrophenyl amine sulfonamide identified in the Color Index as Foron Yellow SE/GLN, CI Disperse Yellow 3, 2,5-dimethoxy-4-sulfonanilide phenylazo-4′-chIoro-2,5-dimethoxy acetoacetanilide and Permanent Yellow FGL.
Other known colorants may be used, such as, Levanyl Black A-SF (Miles, Bayer) and Sunsperse Carbon Black LHD 9303 (Sun Chemicals), and colored dyes, such as, Neopen Blue (BASF), Sudan Blue OS (BASF), PV Fast Blue B2G 01 (American Hoechst), Sunsperse Blue BHD 6000 (Sun Chemicals), Irgalite Blue BCA (CibaGeigy), Paliogen Blue 6470 (BASF), Sudan III (Matheson, Coleman, Bell), Sudan II (Matheson, Coleman, Bell), Sudan IV (Matheson, Coleman, Bell), Sudan Orange G (Aldrich), Sudan Orange 220 (BASF), Paliogen Orange 3040 (BASF), Ortho Orange OR 2673 (Paul Uhlich), Paliogen Yellow 152, 1560 (BASF), Lithol Fast Yellow 0991K (BASF), Paliotol Yellow 1840 (BASF), Neopen Yellow (BASF), Novoperm Yellow FG 1 (Hoechst), Permanent Yellow YE 0305 (Paul Uhlich), Lumogen Yellow D0790 (BASF), Sunsperse Yellow YHD 6001 (Sun Chemicals), Suco-Gelb L1250 (BASF), SUCD-Yellow D1355 (BASF), Hostaperm Pink E (American Hoechst), Fanal Pink D4830 (BASF), Cinquasia Magenta (DuPont), Lithol Scarlet D3700 (BASF), Toluidine Red (Aldrich), Scarlet for Thermoplast NSD PS PA (Ugine Kuhlmann of Canada), E.D. Toluidine Red (Aldrich), Lithol Rubine Toner (Paul Uhlich), Lithol Scarlet 4440 (BASF), Bon Red C (Dominion Color Company), Royal Brilliant Red RD-8192 (Paul Uhlich), Oracet Pink RF (Ciba-Geigy), Paliogen Red 3871K (BASF), Paliogen Red 3340 (BASF), Lithol Fast Scarlet L4300 (BASF), combinations of the foregoing, and the like. Other pigments that may be used, and which are commercially available include various pigments in the color classes, Pigment Yellow 74, Pigment Yellow 14, Pigment Yellow 83, Pigment Orange 34, Pigment Red 238, Pigment Red 122, Pigment Red 48:1, Pigment Red 269, Pigment Red 53:1, Pigment Red 57:1, Pigment Red 83:1, Pigment Violet 23, Pigment Green 7 and so on, and combinations thereof.
The colorant, for example, carbon black, cyan, magenta and/or yellow colorant, may be incorporated in an amount sufficient to impart the desired color to the toner. In general, pigment or dye, may be employed in an amount ranging from about 2% to about 35% by weight of the toner particles on a solids basis, from about 5% to about 25% by weight, from about 5% to about 15% by weight.
In embodiments, more than one colorant may be present in a toner particle. For example, two colorants may be present in a toner particle, such as, a first colorant of pigment blue, may be present in an amount ranging from about 2% to about 10% by weight of the toner particle on a solids basis, from about 3% to about 8% by weight, from about 5% to about 10% by weight; with a second colorant of pigment yellow that may be present in an amount ranging from about 5% to about 20% by weight of the toner particle on a solids basis, from about 6% to about 15% by weight, from about 10% to about 20% by weight and so on.
3. Optional Components
a. Surfactants
In embodiments, toner compositions may be in dispersions including surfactants. Emulsion aggregation methods where the polymer and other components of the toner are in combination may employ one or more surfactants to form an emulsion.
One, two or more surfactants may be used. The surfactants may be selected from ionic surfactants and nonionic surfactants, or combinations thereof. Anionic surfactants and cationic surfactants are encompassed by the term, “ionic surfactants.”
In embodiments, the surfactant or the total amount of surfactants may be used in an amount of from about 0.01% to about 5% by weight of the toner-forming composition, from about 0.75% to about 4% by weight of the toner-forming composition, from about 1% to about 3% by weight of the toner-forming composition.
Examples of nonionic surfactants include, for example, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether and dialkylphenoxy poly(ethyleneoxy) ethanol, for example, available from Rhone-Poulenc as IGEPAL CA-210TM, IGEPAL CA-520TM, IGEPAL CA-720TM, IGEPAL CO-890TM, IGEPAL CO-720TM, IGEPAL CO-290TM, IGEPAL CA-210TM, ANTAROX 890TM and ANTAROX 897TM. Other examples of suitable nonionic surfactants include a block copolymer of polyethylene oxide and polypropylene oxide, including those commercially available as SYNPERONIC® PR/F, in embodiments, SYNPERONIC® PR/F 108; and a DOWFAX, available from The Dow Chemical Corp.
Anionic surfactants include sulfates and sulfonates, such as, sodium dodecylsulfate (SDS), sodium dodecylbenzene sulfonate, sodium dodecylnaphthalene sulfate and so on; dialkyl benzenealkyl sulfates; acids, such as, palmitic acid, and NEOGEN or NEOGEN SC obtained from Daiichi Kogyo Seiyaku, and so on, combinations thereof and the like. Other suitable anionic surfactants include, in embodiments, alkyldiphenyloxide disulfonates or TAYCA POWER BN2060 from Tayca Corporation (JP), which is a branched sodium dodecyl benzene sulfonate. Combinations of those surfactants and any of the foregoing nonionic surfactants may be used in embodiments.
Examples of cationic surfactants include, for example, alkylbenzyl dimethyl ammonium chloride, dialkyl benzenealkyl ammonium chloride, lauryl trimethyl ammonium chloride, alkylbenzyl methyl ammonium chloride, alkyl benzyl dimethyl ammonium bromide, benzalkonium chloride, cetyl pyridinium bromide, trimethyl ammonium bromides, halide salts of quarternized polyoxyethylalkylamines, dodecylbenzyl triethyl ammonium chlorides, MlRAPOL® and ALKAQUAT® available from Alkaril Chemical Company, SANISOL® (benzalkonium chloride) available from Kao Chemicals and the like, and mixtures thereof, including, for example, a nonionic surfactant as known in the art or provided hereinabove.
b. Waxes
The toners of the instant disclosure, optionally, may contain a wax, which may be either a single type of wax or a mixture of two or more different types of waxes (hereinafter identified as, “a wax”). A wax may be added to a toner formulation or to a developer formulation, for example, to improve particular toner properties, such as, toner particle shape, charging, fusing characteristics, gloss, stripping, offset properties and the like. Alternatively, a combination of waxes may be added to provide multiple properties to a toner or a developer composition. A wax may be included as, for example, a fuser roll release agent.
The wax may be combined with the resin-forming composition for forming toner particles. When included, the wax may be present in an amount of, for example, from about 1 wt % to about 25 wt % of the toner particles, from about 5 wt % to about 20 wt % of the toner particles.
Waxes that may be selected include waxes having, for example, a weight average molecular weight of from about 500 to about 20,000, from 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 that are commercially available, for example, POLYWAXTM polyethylene waxes from Baker Petrolite, wax emulsions available from Michaelman, Inc. or Daniels Products Co., EPOLENE N15TM which is commercially available from Eastman Chemical Products, Inc., VISCOL 550-PTM, a low weight average molecular weight polypropylene available from Sanyo Kasei K.K.; 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 wax, paraffin wax, microcrystalline wax and Fischer-Tropsch waxes; ester waxes obtained from higher fatty acids and higher alcohols, such as, stearyl stearate and behenyl behenate; ester waxes obtained from higher fatty acids and monovalent or multivalent lower alcohols, such as, butyl stearate, propyl oleate, glyceride monostearate, glyceride distearate and pentaerythritol tetrabehenate; ester waxes obtained from higher fatty acids and multivalent alcohol multimers, such as, diethyleneglycol monostearate, dipropyleneglycol distearate, diglyceryl distearate and triglyceryl tetrastearate; sorbitan higher fatty acid ester waxes, such as, sorbitan monostearate; cholesterol higher fatty acid ester waxes, such as, cholesteryl stearate, and so on.
Examples of functionalized waxes that may be used include, for example, amines and amides, for example, AQUA SUPERSLIP 6550TM and SUPERSLIP 6530TM available from Micro Powder Inc.; fluorinated waxes, for example, POLYFLUO 190TM, POLYFLUO 200TM, POLYSILK 19TM and POLYSILK 14TM available from Micro Powder Inc.; mixed fluorinated amide waxes, for example, MICROSPERSION 19TM also available from Micro Powder Inc.; imides, esters, quaternary amines, carboxylic acids, acrylic polymer emulsions, for example, JONCRYL 74TM, 89TM, 130TM, 537TM and 538TM available from SC Johnson Wax; and chlorinated polypropylenes and polyethylenes available from Allied Chemical, Petrolite Corp. and SC Johnson. Mixtures and combinations of the foregoing waxes also may be used in embodiments.
c. Aggregating Factor
An aggregating factor may be an inorganic cationic coagulant, such as, for example, polyaluminum chloride (PAC), polyaluminum sulfosilicate (PASS), aluminum sulfate, zinc sulfate, magnesium sulfate, chlorides of magnesium, calcium, zinc, beryllium, aluminum, sodium, other metal halides including monovalent, divalent and trivalent halides.
The aggregating factor may be present in an emulsion in an amount of from, for example, from about 0.01 to about 10 wt %, from about 0.05 to about 5 wt % based on the total solids in the toner.
The aggregating factor may also contain minor amounts of other components, for example, nitric acid.
In embodiments, a sequestering agent or chelating agent may be introduced after aggregation is complete to sequester or extract a metal complexing ion, such as, aluminum from the aggregation process. Thus, the sequestering, chelating or complexing agent used after aggregation is complete may comprise an organic complexing component, such as, ethylenediaminetetraacetic acid (EDTA), gluconal, hydroxyl-2,2′iminodisuccinic acid (HIDS), dicarboxylmethyl glutamic acid (GLDA), methyl glycidyl diacetic acid (MGDA), hydroxydiethyliminodiacetic acid (HIDA), potassium citrate, sodium citrate, nitrotriacetate salt, humic acid, fulvic acid; salts of EDTA, such as, alkali metal salts of EDTA, tartaric acid, oxalic acid, polyacrylates, sugar acrylates, citric acid, polyasparic acid, diethylenetriamine pentaacetate, 3-hydroxy-4-pyridinone, dopamine, eucalyptus, iminodisuccinic acid, ethylenediaminedisuccinate, polysaccharide, sodium ethylenedinitrilotetraacetate, thiamine pyrophosphate, farnesyl pyrophosphate, 2-aminoethylpyrophosphate, hydroxyl ethylidene-1,1-diphosphonic acid, aminotrimethylenephosphonic acid, diethylene triaminepentamethylene phosphonic acid, ethylenediamine tetramethylene phosphonic acid and mixtures thereof.
d. Surface Additive
In embodiments, the toner particles may be mixed with one or more of silicon dioxide or silica (SiO2), titania or titanium dioxide (TiO2) and/or cerium oxide. Silica may be a first silica and a second silica. The first silica may have an average primary particle size, measured in diameter, in the range of, for example, from about 5 nm to about 50 nm, from about 5 nm to about 25 nm, from about 20 nm to about 40 nm. The second silica may have an average primary particle size, measured in diameter, in the range of, for example, from about 100 nm to about 200 nm, from about 100 nm to about 150 nm, from about 125 nm to about 145 nm. The second silica may have a larger average size (diameter) than the first silica. The titania may have an average primary particle size in the range of, for example, about 5 nm to about 50 nm, from about 5 nm to about 20 nm, from about 10 nm to about 50 nm. The cerium oxide may have an average primary particle size in the range of, for example, about 5 nm to about 50 nm, from about 5 nm to about 20 nm, from about 10 nm to about 50 nm.
Zinc stearate also may be used as an external additive. Calcium stearate and magnesium stearate may provide similar functions. Zinc stearate may have an average primary particle size in the range of, for example, from about 500 nm to about 700 nm, such as, from about 500 nm to about 600 nm, from about 550 nm to about 650 nm.
e. Carrier
Carrier particles include those that are capable of triboelectrically obtaining a charge of polarity opposite to that of the toner particles. Illustrative examples of suitable carrier particles include granular zircon, granular silicon, glass, steel, nickel, ferrites, iron ferrites, silicon dioxide, nickel berry carriers as disclosed in U.S. Pat. No. 3,847,604, the entire disclosure of each of which is hereby incorporated herein by reference, comprised of nodular carrier beads of nickel, characterized by surfaces of reoccurring recesses and protrusions thereby providing particles with a relatively large external area, those disclosed in U.S. Pat. Nos. 4,937,166 and 4,935,326, the disclosure of each of which hereby is incorporated herein by reference, and so on. In embodiments, the carrier particles may have an average particle size of, for example, from about 20 to about 85 μm, from about 30 to about 60 μm, from about 35 to about 50 μm.
B. Toner Particle Preparation
1. Method
a. Particle Formation
The toner particles may be prepared by any method within the purview of one skilled in the art, for example, any of the emulsion/aggregation methods may be used with the polyester resin as described herein. However, any suitable method of preparing toner particles may be used, including chemical processes, such as, suspension and encapsulation processes disclosed, for example, in U.S. Pat. Nos. 5,290,654 and 5,302,486, the disclosure of each of which hereby is incorporated by reference in entirety; by conventional granulation methods, such as, jet milling; pelletizing slabs of material; other mechanical processes; any process for producing nanoparticles or microparticles; and so on.
In embodiments relating to an emulsification/aggregation process, a resin may be dissolved in a solvent, and may be mixed into an emulsion medium, for example water, such as, deionized water (DIW), optionally containing a stabilizer, and optionally a surfactant.
Examples of suitable stabilizers include water-soluble alkali metal hydroxides, such as, sodium hydroxide, potassium hydroxide, lithium hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide or barium hydroxide; ammonium hydroxide; alkali metal carbonates, such as, sodium bicarbonate, lithium bicarbonate, potassium bicarbonate, lithium carbonate, potassium carbonate, sodium carbonate, beryllium carbonate, magnesium carbonate, calcium carbonate, barium carbonate or cesium carbonate; or mixtures thereof. When a stabilizer is used, the stabilizer may be present in amounts of from about 0.1% to about 5%, from about 0.5% to about 3% by weight of the resin.
Optionally, a surfactant may be added to the aqueous emulsion medium, for example, to afford additional stabilization of or to the resin or to enhance emulsification of the resin. Suitable surfactants include anionic, cationic and nonionic surfactants as taught herein.
Following emulsification, toner compositions may be prepared by aggregating a mixture of a resin, a pigment, an optional wax and any other desired additives in an emulsion, optionally, with surfactants as described above, and then optionally coalescing the aggregate mixture. A mixture may be prepared by adding an optional wax or other materials, which may also be optionally in a dispersion, including a surfactant, to the emulsion comprising a resin-forming material and a pigments, which may be a mixture of two or more emulsions containing the requisite reagents. The pH of the resulting mixture may be adjusted with an acid, such as, for example, acetic acid, nitric acid or the like. In embodiments, the pH of the mixture may be adjusted to from about 2 to about 4.5.
Additionally, in embodiments, the mixture may be homogenized. If the mixture is homogenized, mixing may be at from about 600 to about 4,000 rpm. Homogenization may be by any suitable means, including, for example, an IKA ULTRA TURRAX T50 probe homogenizer.
b. Aggregation
Following preparation of the above mixture, often, it is desirable to form larger particles or aggregates, often sized in micrometers, of the smaller particles from the initial polymerization reaction, often sized in nanometers. An aggregating factor may be added to the mixture. Suitable aggregating factors include, for example, aqueous solutions of a divalent cation, a multivalent cation or a compound comprising same.
The aggregating factor, as provided above, may be, for example, a polyaluminum halide, such as, polyaluminum chloride (PAC) or the corresponding bromide, fluoride or iodide; a polyaluminum silicate, such as, polyaluminum sulfosilicate (PASS); or a water soluble metal salt, including, aluminum chloride, aluminum nitrite, aluminum sulfate, potassium aluminum sulfate, calcium acetate, calcium chloride, calcium nitrite, calcium oxylate, calcium sulfate, magnesium acetate, magnesium nitrate, magnesium sulfate, zinc acetate, zinc nitrate, zinc sulfate, zinc chloride, zinc bromide, magnesium bromide, copper chloride, copper sulfate or combinations thereof.
In embodiments, the aggregating factor may be added to the mixture at a temperature that is below the glass transition temperature (Tg) of the resin or of a polymer.
The aggregating factor may be added to the mixture components to form a toner in an amount of, for example, from about 0.1 part per hundred (pph) to about 1 pph, from about 0.25 pph to about 0.75 pph, about 0.5 pph of the reaction mixture.
To control aggregation of the particles, the aggregating factor may be metered into the mixture over time. For example, the factor may be added incrementally into the mixture over a period of from about 5 to about 240 minutes, from about 30 to about 200 minutes.
Addition of the aggregating factor also may be done while the mixture is maintained under stirred conditions, in embodiments, from about 50 rpm to about 1,000 rpm, from about 100 rpm to about 500 rpm; and at a temperature that is below the Tg of the resin or polymer or is below the melting point of the resin(s), in embodiments, from about 30° C. to about 90° C., from about 35° C. to about 70° C. The growth and shaping of the particles following addition of the aggregation factor may be accomplished under any suitable condition(s). Higher or lower temperatures may be used, it being understood that the temperature is a function of the polymer(s) used for the core and/or shell.
The particles may be permitted to aggregate until a predetermined desired particle size is obtained. Particle size may be monitored during the growth process. For example, samples may be taken during the growth process and analyzed, for example, with a COULTER COUNTER, for average particle size. The aggregation thus may proceed by maintaining the mixture, for example, at elevated temperature, or slowly raising the temperature, 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, from about hour 1 to about 5 hours, while maintaining stirring, to provide the desired aggregated particles. Once the predetermined desired particle size is attained, the growth process is halted.
Once the desired final size of the toner particles or aggregates is achieved, the pH of the mixture may be adjusted with base to a value of from about 6 to about 10, in embodiments, from about 6.2 to about 7. The adjustment of pH may be used to freeze, that is, to stop, toner particle growth. The base used to stop toner particle growth may be, for example, an alkali metal hydroxide, such as, for example, sodium hydroxide, potassium hydroxide, ammonium hydroxide, combinations thereof and the like. In embodiments, EDTA may be added to assist adjusting the pH to the desired value. The base may be added in amounts from about 2 to about 25% by weight of the mixture, from about 4 to about 10% by weight of the mixture.
The characteristics of the toner particles may be determined by any suitable technique and apparatus. Volume average particle diameter and geometric standard deviation may be measured using an instrument, such as, a BECKMAN COULTER MULTISIZER 3.
For separate aggregation and coalescence stages, the aggregation process may be conducted under shearing conditions at an elevated temperature, for example, of from about 40° C. to about 90° C., from about 45° C. to about 80° C., which may be below the Tg of the resin or a polymer.
In embodiments, the aggregate particles may be of a size of less than about 8 μm, less than about 6 μm, in embodiments, less than about 4 μm.
c. Coalescence
Following aggregation to a desired particle size and application of any optional shell, the particles then may be coalesced to a desired final shape, such as, a circular shape, for example, to correct for irregularities in shape and size, the coalescence being achieved by, for example, heating the mixture to a temperature from about 45° C. to about 100° C., from about 55° C. to about 99° C., which may be at or above the Tg of the resins used to form the toner particles or below the melting points of the resins(s), and/or reducing the stirring, for example, to from about 1000 rpm to about 100 rpm, from about 800 rpm to about 200 rpm. Higher or lower temperatures may be used, it being understood that the temperature is a function of the polymer(s) used for the core and/or shell. Coalescence may be conducted over a period from about 0.01 to about 9 hours, from about 0.1 to about 4 hours, see, for example, U.S. Pat. No. 7,736,831.
After aggregation and/or coalescence, the mixture may be cooled to room temperature, such as, from about 20° C. to about 25° C. The cooling may be rapid or slow, as desired. A suitable cooling method may include introducing cold water to a jacket around the reactor. After cooling, the toner particles optionally may be washed with water and then dried. Drying may be by any suitable method, including, for example, freeze-drying.
Optionally, a coalescing agent may be used. Examples of suitable coalescence agents include, but are not limited to, benzoic acid alkyl esters, ester alcohols, glycol/ether-type solvents, long chain aliphatic alcohols, aromatic alcohols, mixtures thereof and the like. Examples of benzoic acid alkyl esters include those where the alkyl group, which may be straight or branched, substituted or unsubstituted, has from about 2 to about 30 carbon atoms, such as decyl or isodecyl benzoate, nonyl or isononyl benzoate, octyl or isooctyl benzoate, 2-ethylhexyl benzoate, tridecyl or isotridecyl benzoate, 3,7-dimethyloctyl benzoate, 3,5,5-trimethylhexyl benzoate, mixtures thereof and the like. Examples of such benzoic acid alkyl esters include VELTA® 262 (isodecyl benzoate) and VELTA® 368 (2-ethylhexyl benzoate) available from Velsicol Chemical Corp. Examples of ester alcohols include hydroxyalkyl esters of alkanoic acids, where the alkyl group, which may be straight or branched, substituted or unsubstituted, and may have from about 2 to about 30 carbon atoms, such as, 2,2,4-trimethylpentane-1,3-diol monoisobutyrate. An example of an ester alcohol is TEXANOL® (2,2,4-trimethylpentane-1,3-diol monoisobutyrate) available from Eastman Chemical Co. Examples of glycol/ether-type solvents include diethylene glycol monomethylether acetate, diethylene glycol monobutylether acetate, butyl carbitol acetate (BCA) and the like. Examples of long chain aliphatic alcohols include those where the alkyl group is from about 5 to about 20 carbon atoms, such as, ethylhexanol, octanol, dodecanol and the like. Examples of aromatic alcohols include benzyl alcohol and the like.
In embodiments, the coalescence agent (or coalescing agent or coalescence aid agent) evaporates during later stages of the emulsion/aggregation process, such as, during a second heating step, that is, generally above the Tg of the resin or a polymer. The final toner particles are thus, free of, or essentially or substantially free of any remaining coalescence agent. To the extent that any remaining coalescence agent may be present in a final toner particle, the amount of remaining coalescence agent is such that presence thereof does not affect any properties or the performance of the toner or developer.
The coalescence agent may be added prior to the coalescence or fusing step in any desired or suitable amount. For example, the coalescence agent may be added in an amount of from about 0.01 to about 10% by weight, based on the solids content in the reaction medium, from about 0.05, from about 0.1%, to about 0.5, to about 3.0% by weight, based on the solids content in the reaction medium. Of course, amounts outside those ranges may be used, as desired.
In embodiments, the coalescence agent may be added at any time between aggregation and coalescence, although in some embodiments it may be desirable to add the coalescence agent after aggregation is, “frozen,” or completed, for example, by adjustment of pH, for example, by addition, for example, of base.
Coalescence may proceed and be accomplished over a period of from about 0.1 to about 9 hours, in embodiments, from about 0.5 to about 4 hours.
After coalescence, the mixture may be cooled to room temperature, such as, from about 20° C. to about 25° C. The cooling may be rapid or slow, as desired. A suitable cooling method may include introducing cold water in a jacket around the reactor. After cooling, the toner particles optionally may be washed with water and then dried. Drying may be accomplished by any suitable method for drying including, for example, freeze drying.
d. Shells
In embodiments, an optional shell may be applied to the formed toner particles, aggregates or coalesced particles. Any polymer, including those described above as suitable for the core, may be used for the shell. The shell polymer may be applied to the particles or aggregates by any method within the purview of those skilled in the art.
In embodiments, an amorphous polyester resin may be used to form a shell over the particles or aggregates to form toner particles or aggregates having a core-shell configuration. In embodiments, a low molecular weight amorphous polyester resin may be used to form a shell over the particles or aggregates.
The shell polymer may be present in an amount of from about 1% to about 80% by weight of the toner particles or aggregates, from about 10% to about 40% by weight of the toner particles or aggregates.
e. Optional Additives
In embodiments, the toner particles also may contain other optional additives.
i. Charge Additives
The toner may include any known charge additives in amounts of from about 0.1 to about 10 weight %, from about 0.5 to about 7 weight % of the toner. Examples of such charge additives include alkyl pyridinium halides, bisulfates, the charge control additives of U.S. Pat. Nos. 3,944,493; 4,007,293; 4,079,014; 4,394,430; and 4,560,635, the disclosure of each of which hereby is incorporated by reference in entirety, negative charge enhancing additives, such as, aluminum complexes, and the like.
Charge enhancing molecules may be used to impart either a positive or a negative charge on a toner particle. Examples include quaternary ammonium compounds, see, for example, U.S. Pat. No. 4,298,672, organic sulfate and sulfonate compounds, see for example, U.S. Pat. No. 4,338,390, cetyl pyridinium tetrafluoroborates, distearyl dimethyl ammonium methyl sulfate, aluminum salts and so on.
Such enhancing molecules may be present in an amount of from about 0.1 to about 10%, from about 1 to about 3% by weight.
ii. Surface Modifications
Surface additives may be added to the toner compositions of the present disclosure, for example, after washing or drying. Examples of such surface additives include, for example, one or more of a metal salt, a metal salt of a fatty acid, a colloidal silica, a metal oxide, such as, TiO2 (for example, for improved RH stability, tribo control and improved development and transfer stability), an aluminum oxide, a cerium oxide, a strontium titanate, SiO2, mixtures thereof and the like. Examples of such additives include those disclosed in U.S. Pat. Nos. 3,590,000; 3,720,617; 3,655,374; and 3,983,045, the disclosure of each of which is hereby incorporated by reference in entirety.
Surface additives may be used in an amount of from about 0.1 to about 10 wt %, from about 0.5 to about 7 wt % of the toner.
Other surface additives include lubricants, such as, a metal salt of a fatty acid (e.g., zinc or calcium stearate) or long chain alcohols, such as, UNILIN 700 available from Baker Petrolite and AEROSIL R972® available from Degussa. The coated silicas of U.S. Pat. Nos. 6,190,815 and 6,004,714, the disclosure of each of which hereby is incorporated by reference in entirety, also may be present. The additive may be present in an amount of from about 0.05 to about 5%, in embodiments, of from about 0.1 to about 2% of the toner, which additives may be added during the aggregation or blended into the formed toner product.
The gloss of a toner may be influenced by the amount of retained metal ion, such as, Al3+, in a particle. The amount of retained metal ion may be adjusted further by the addition of a chelator, such as, EDTA. In embodiments, the amount of retained catalyst, for example, Al3+, in toner particles of the present disclosure may be from about 0.1 pph to about 1 pph, from about 0.25 pph to about 0.8 pph. The gloss level of a toner of the instant disclosure may have a gloss, as measured by Gardner gloss units (gu), of from about 20 gu to about 100 gu, from about 50 gu to about 95 gu, from about 60 gu to about 90 gu.
Toners may possess suitable charge characteristics when exposed to extreme relative humidity (RH) conditions. The low humidity zone (C zone) may be about 10° C. and 15% RH, while the high humidity zone (A zone) may be about 28° C. and 85% RH.
Toners of the instant disclosure also may possess a parent toner charge per mass ratio (q/m) of from about −5 μC/g to about −90 μC/g, and a final toner charge after surface additive blending of from about −15 μC/g to about −80 μC/g.
The dry toner particles, exclusive of external surface additives, may have: (1) a volume average diameter (also referred to as “volume average particle diameter”) of from about 2.5 to about 20 μm, from about 2.75 to about 10 μm, from about 3 to about 7.5 μm; (2) a number average geometric standard deviation (GSDn) and/or volume average geometric standard deviation (GSDv) of from about 1.15 to about 1.30, from about 1.20 to about 1.25; and (3) circularity of from about 0.9 to about 1.0 (measured with, for example, a Sysmex FPIA 2100 analyzer), from about 0.95 to about 0.985, from about 0.96 to about 0.98.
III. Developers
A. Composition
The toner particles thus formed may be formulated into a developer composition. For example, the toner particles may be mixed with carrier particles to achieve a two component developer composition. The toner concentration in the developer may be from about 1% to about 25% by weight of the total weight of the developer, from about 2% to about 15% by weight of the total weight of the developer, with the remainder of the developer composition being the carrier. However, different toner and carrier percentages may be used to achieve a developer composition with desired characteristics.
1. Carrier
Examples of carrier particles for mixing with the toner particles include those particles that are capable of triboelectrically obtaining a charge of polarity opposite to that of the toner particles. Illustrative examples of suitable carrier particles include granular zircon, granular silicon, glass, steel, nickel, ferrites, iron ferrites, silicon dioxide, one or more polymers and the like. Other carriers include those disclosed in U.S. Pat. Nos. 3,847,604; 4,937,166; and 4,935,326.
In embodiments, the carrier particles may include a core with a coating thereover, which may be formed from a polymer or a mixture of polymers that are not in close proximity thereto in the triboelectric series, such as, those as taught herein or as known in the art. The coating may include fluoropolymers, such as polyvinylidene fluorides, terpolymers of styrene, methyl methacrylates, silanes, such as triethoxy silanes, tetrafluoroethylenes, other known coatings and the like. For example, coatings containing polyvinylidenefluoride, available, for example, as KYNAR 301FTM, and/or polymethylmethacrylate (PMMA), for example, having a weight average molecular weight of about 300,000 to about 350,000, such as, commercially available from Soken, may be used. In embodiments, PMMA and polyvinylidenefluoride may be mixed in proportions of from about 30 to about 70 wt % to about 70 to about 30 wt %, from about 40 to about 60 wt % to about 60 to about 40 wt %. The coating may have a coating weight of, for example, from about 0.1 to about 5% by weight of the carrier, from about 0.5 to about 2% by weight of the carrier.
The carrier particles may be prepared by mixing the carrier core with polymer in an amount from about 0.05 to about 10% by weight, from about 0.01 to about 3% by weight, based on the weight of the coated carrier particle, until adherence thereof to the carrier core is obtained, for example, by mechanical impaction and/or electrostatic attraction.
In embodiments, suitable carriers may include a steel core, for example, of from about 25 to about 100 μm in size, from about 50 to about 75 μm in size, coated with about 0.5% to about 10% by weight, from about 0.7% to about 5% by weight of a polymer mixture including, for example, methylacrylate and carbon black, using the process described, for example, in U.S. Pat. Nos. 5,236,629 and 5,330,874.
IV. Devices Comprising a Toner Particle
Toners and developers may be combined with a number of devices ranging from enclosures or vessels, such as, a vial, a bottle, a flexible container, such as a bag or a package, and so on, to devices that serve more than a storage function.
A. Imaging Device Components
The toner compositions and developers of interest may be incorporated into devices dedicated, for example, to delivering same for a purpose, such as, forming an image. Hence, particularized toner delivery devices are known, see, for example, U.S. Pat. No. 7,822,370, and may contain a toner preparation or developer of interest. Such devices include cartridges, tanks, reservoirs and the like, and may be replaceable, disposable or reusable. Such a device may comprise a storage portion; a dispensing or delivery portion; and so on; along with various ports or openings to enable toner or developer addition to and removal from the device; an optional portion for monitoring amount of toner or developer in the device; formed or shaped portions to enable siting and seating of the device in, for example, an imaging device; and so on.
B. Toner or Developer Delivery Device
A toner or developer of interest may be included in a device dedicated to delivery thereof, for example, for recharging or refilling toner or developer in an imaging device component, such as, a cartridge, in need of toner or developer, see, for example, U.S. Pat. No. 7,817,944, wherein the imaging device component may be replaceable or reusable.
V. Imaging Devices
The toners or developers may be used for electrostatographic or electrophotographic processes, including those disclosed in U.S. Pat. No. 4,295,990, the disclosure of which hereby is incorporated by reference in entirety. In embodiments, any known type of image development system may be used in an image developing device, including, for example, magnetic brush development, jumping single component development, hybrid scavengeless development (HSD) and the like. Those and similar development systems are within the purview of those skilled in the art.
Color printers commonly use four housings carrying different colors to generate full color images based on black plus the standard printing colors, cyan, magenta and yellow. However, in embodiments, additional housings may be desirable, including image generating devices possessing five housings, six housings or more, thereby providing the ability to carry additional toner colors to print an extended range of colors (extended gamut).
The following Examples illustrate embodiments of the instant disclosure. The Examples are intended to be illustrative only and are not intended to limit the scope of the present disclosure. Parts and percentages are by weight unless otherwise indicated. As used herein, “room temperature,” (RT) refers to a temperature of from about 20° C. to about 30° C.
EXAMPLES
Preparative Example 1
Synthesis of Terpinene-Maleic Anhydride Adduct




α-Terpinene (219 g) was loaded into a 500 ml, three-neck round-bottom flask fitted with a magnetic stir bar, thermometer, and distillation head. The terpinene was warmed to 60° C. and 146 g of maleic anhydride were slowly added (with intermittent cooling) such that the reaction temperature was maintained between 65-75° C. When maleic anhydride addition was complete, the mixture was heated to 100° C. and distillate collected in a cooled trap. The material remaining after distillation was transferred to a tared flask and allowed to cool. Yield was 346 g (99%).
Preparative Example 2
Synthesis of Phellandrene-maleic Anhydride Adduct




α-Phellandrene (228 g) was loaded into a 500 ml, three-neck round-bottomed flask fitted with a magnetic stir bar, thermometer, and distillation head. The phellandrene was warmed to 60° C. and 127 g of maleic anhydride was slowly added (with intermittent cooling) such that the reaction temperature was maintained between 60-110° C. A persistent solid material had formed when maleic anhydride addition was complete. The resulting slurry was transferred to a beaker and washed three times with 100 ml portions of hexane. The material remaining after washing was transferred to a Buchner funnel and allowed to dry. Yield 273 g (91%).
Preparative Example 3
Synthesis of Terpinene-dimethyl Fumarate Adduct




α-Terpinene (7.3 g), dimethyl fumarate (5.0 g), and a trace quantity of hydroquinone were heated at 140° C. for 96 hr under nitrogen. The reaction mixture was then briefly distilled under reduced pressure (0.1 mmHg) and the material remaining was cooled to room temperature (quantitative yield).
Example 1
Control Resin
A 1 liter Parr reactor equipped with a mechanical stirrer, bottom drain valve and distillation apparatus was charged with dimethyl 2,6-naphthalene dicarboxylate (NDC, 100.65 g, 0.412 moles, 0.121 eq), 1,2-propylene glycol (PPG, 193.86 g, 2.135 moles, 0.508 eq; excess 0.121 eq), rosin fumarate (rosin-FA, 66.2 g, 0.163 moles, 0.048 eq), rosin acrylate (rosin-Ar, 80.0 g, 0.226 moles, 0.067 eq), dodecenyl succinic anhydride (DDSA; 106.9 g, 0.402 moles, 0.119 eq), succinic acid (SA, 48.6 g, 0.412 moles, 0.121 eq) followed by 1.0 g of both Fascat 4100 and Vertec AC422 titanium catalyst. The reactor was blanketed with nitrogen and the temperature of the reactor was slowly raised to 170° C. with stirring (once the solids melted). The reaction mixture was maintained for 23 hours under nitrogen at 200° C. while methanol was continuously collected in a collection flask. The reaction mixture was heated to 205° C. and low vacuum was applied. The vacuum was switched to a higher vacuum (<0.1 Torr). During that time, propylene glycol distilled off and when the softening point of the resin reached 100° C., the reactor temperature was reduced to 180° C. and the second portion of rosin fumarate (rosin-FA, 21.2 g, 0.052 moles, 0.0154 eq) was added. The reaction mixture temperature was slowly raised to 220° C. while under high vacuum for another 6.5 hours until a softening point of 111.2° C. was achieved. The temperature was then lowered to 190° C. and the polymer was discharged onto a polytetrafluoroethylene (Teflon) pan.
Example 2
Terpinene Resin
A 1 liter Parr reactor equipped with a mechanical stirrer, bottom drain valve and distillation apparatus, was charged with NDC (111.0 g, 0.453 moles, 0.121 eq), PPG (211.0 g, 2.768 moles, 0.508 eq; excess 0.232 eq), terpinene-maleic anhydride adduct (42 g, 0.180 moles, 0.048 eq), Rosin-Ar (88 g, 0.249 moles, 0.0667 eq), DDSA (118 g, 0.445 moles, 0.119 eq), SA (53.0 g, 0.453 moles, 0.121 eq) followed by 1.0 g of both Fascat 4100 and Vertec AC422 titanium catalyst. About 0.4 g of hydroquinone were added as a free radical scavenger to prevent crosslinking of resin. The reactor was blanketed with nitrogen and the temperature of the reactor was slowly raised to 170° C. with stirring (once the solids melted). The reaction mixture was maintained for 15 hours under nitrogen at 205° C. while methanol was continuously collected in a collection flask. The reaction mixture was heated to 215° C. and low vacuum was applied. A higher vacuum (<0.1 Torr) was applied. During that time, propylene glycol distilled off and when the softening point of the resin reached 97.8° C., the reactor temperature was reduced to 180° C. and the second portion of terpinene-maleic anhydride (14 g, 0.058 moles, 0.0154 eq) was added. The reaction mixture temperature was slowly raised to 225° C. while under high vacuum for another 10 hours until a softening point of 103.5° C. was achieved. The temperature was then lowered to 190° C. and the polymer was discharged onto a polytetrafluoroethylene (Teflon) pan.







TABLE 1







Synthesis of Polymers containing Terpinene-Maleic Anhydride Adduct to


replace Fumarated Rosin.























Rosin-
Rosin-FA1
1,2-





Mn/


Resin ID
NDC
SA
DDSA
Ar
Terpinene2
PPG
C/O
BM
Ts
Tg
A.V.
Mw





Control
0.121
0.121
0.119
0.067
0.0641
0.508
4.19
57.8
111.2
44.0
8.0
3,952/














73,240


Experimental
0.121
0.121
0.119
0.067
0.0642
0.508
4.05
57.1
103.5
39.7
5.8
3,610/














16,782





C/O: carbon over oxygen ratio;


BM: biomass;


AV: acid value.






The experimental terpinene-based resin has properties similar to that of the control resin. Reducing the amount of DDSA, which contributes to resin softness and/or reacting at a higher temperature for a longer period of time can result in Ts>115° C. and Tg>50° C.
Example 3
Phellandrene Resin I
A 1 liter Parr reactor equipped with a mechanical stirrer, bottom drain valve and distillation apparatus, was charged with 1,3-propanediol (1,3-PD, 1.12 mol, 0.53 eq., 85.0 g) and phellandrene-maleic anhydride (Phell adduct, 1.07 mol, 0.47 eq., 250.0 g) followed by 0.178 g of Fascat 4100. The reactor was blanketed with nitrogen and the temperature of the reactor was slowly raised to 170° C. with stirring (once the solids melted). The reaction mixture was maintained for 8.5 hours under nitrogen at 205° C. while water was continuously collected in a collection flask. The reaction mixture was heated to 215° C. and low vacuum was applied. The polymerization was held under low vacuum for 17 hours. Next day, high vacuum was applied with no reflux and was held at 220° C. under vacuum for 7 hours. The reaction was concluded once the softening point reached 56.2° C.
Example 4
Phellandrene Resin II
A 1 liter Parr reactor equipped with a mechanical stirrer, bottom drain valve and distillation apparatus was charged with 1,3-PD (1.28 mol, 0.50 eq., 97.43 g), NDC (0.64 mol, 0.25 eq., 156.37 g) and Phell adduct (0.64 mol, 0.25 eq., 150.0 g) followed by 0.40 g of Fascat 4100. The reactor was blanketed with nitrogen and the temperature of the reactor was slowly raised to 190° C. with stirring (once the solids melted). The reaction mixture was maintained for 17 hours under nitrogen at 200° C. while methanol and water were continuously collected in a collection flask. The reaction mixture temperature was lowered to 190° C. and low vacuum was applied for 16 hours. A higher vacuum (<0.1 Torr) was applied once refluxing subsided. During that time, more water distilled off. The polymerization was held under high vacuum for 4.5 hours. The reaction was concluded once the softening point reached 61.1° C.
Those two examples of phellandrene-maleic anhydride-based resins illustrated polymerization of a pre-polymer or macromer can be further reacted with other monomers to obtain higher molecular weight and Tg.







TABLE 2







Synthesis of Pre-polymers (or Macromers) containing Phellandrene-Maleic


Anhydride Adduct.













Monomers (mol eq.)

Ts

GPC
















Resin
Phell Adduct
1,3-PD
NDC
C/O
DSC Tg(on)
(° C.)
Acid Value
Mn
Mw





I
0.47
0.53
—
3.12
19.7
56.2
12.0
3490
1640


II
0.25
0.50
0.25
3.42
11.2
61.1
47.9
2210
1040









It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art, which are also intended to be encompassed by the following claims. Unless specifically recited in a claim, steps or components of claims should not be implied or imported from the specification or any other claims as to any particular order, number, position, size, shape, angle, color or material.
All references cited herein are herein incorporated by reference in entirety.

## Claims

1. A toner polyester resin comprising: a) a polyacid monomer comprising a Diels-Alder reaction adduct, wherein a diene thereof comprises a substituted cyclohexadiene component of an essential oil and a dienophile thereof is selected from the group consisting of maleic acid, maleic anhydride, fumaric acid and esters thereof, and b) a polyol monomer, wherein the polyester resin has an Mn of from about 500 to about 20,000 g/mol, and wherein the resin has an Mw of between about 2,000 g/mol and about 75,000 g/mol.

2. The toner resin of claim 1, wherein the substituted cyclohexadiene is 1-methyl-4-(propan-2-yl)cyclohexa-1,3-diene (α-terpinene) or 2-methyl-5-(propan-2-yl)cyclohexa-1,3-diene (α-phellandrene).

3. The toner resin of claim 1, wherein Ts of the resin is between about 80° C. and about 130° C.

4. The toner resin of claim 1, wherein the acid value of the resin is from about 3 to about 70 meq KOH/g.

5. The toner resin of claim 1, wherein said polyol monomer comprises at least about three hydroxyl groups.

6. The toner resin of claim 1, wherein the resin has a Tg onset of between about 20° and 90° C.

7. The toner resin of claim 1, wherein the polyester resin has an Mn of between about 750 g/mol to about 15,000 g/mol.

8. The toner resin of claim 1, further comprising a second polyacid monomer.

9. The toner resin of claim 7, further comprising a second polyacid monomer.

10. The toner resin of claim 1, wherein the resin comprises a carbon to oxygen ration of at least 3.

11. A toner particle comprising the resin of claim 1, an optional colorant; and an optional wax, wherein the toner particle has a volume average particle diameter of from about 2.5 to about 20 μm.

12. The toner of claim 11, further comprising a crystalline resin.

13. The toner of claim 11, which is an emulsion aggregation toner.

14. The toner of claim 11, further comprising an amorphous resin.

15. The toner of claim 11, comprising a shell.

16. A toner polyester resin comprising a Diels-Aider reaction adduct monomer composing 1-methyl-4-(propan-2-yl)cyclohexa-1,3-diene (α-terpinene) or 2-methyl-5-(propan-2-yl)cyclobexa-1,3-diene (α-phellandrene) and a dicarboxylic acid or a cyclic anhydride; and a polyol monomer, wherein the polyester resin has an Mn of from about 500 to about 20,000 g/mol, and wherein the resin has an Mw of between about 2,000 g/mol and about 75,000 g/mol.

17. The toner resin of claim 16, further comprising a second polyacid or polyester monomer.

18. The toner resin of claim 16, wherein the cyclic anhydride is maleic anhydride.

19. The toner resin of claim 16, wherein the dicarboxylic acid is maleic acid.

20. The toner resin of claim 16, wherein the dicarboxylic acid is iiimaric acid.