Toner compositions with metal complex charge enhancing additives

A negatively charged toner composition comprised of resin particles, pigment particles, and an aluminum charge enhancing additive obtained from the reaction of an aluminum inorganic salt solution, and coumarin-3-carboxylic acid.

BACKGROUND OF THE INVENTION 
The invention is generally directed to toner and developer compositions, 
and more specifically, the present invention is directed to developer and 
toner compositions containing charge enhancing additives, which impart or 
assist in imparting a negative charge to the toner particles and enable 
toners with rapid triboelectric charging characteristics. In one 
embodiment, there are provided in accordance with the present invention 
toner compositions comprised of a polymer or polymer resins, pigment 
particles or dye molecules, and certain metal salts, especially aluminum, 
charge enhancing additives. In another embodiment, the present invention 
is directed to toners with aluminum charge enhancing additives, which 
additives can be obtained from the reaction of, for example, xanthene, 
especially xanthene-9-carboxylic acid or coumarin, especially 
coumarin-3-carboxylic acid or a mixture thereof, with an aqueous solution 
of an aluminum inorganic salt. The aforementioned charge additives, 
especially bis(xanthene-9-carboxylato)hydroxy aluminum, 
bis(coumarin-3-carboxylato)hydroxy aluminum, or 
(coumarin-3-carboxylato)(xanthene-9-carboxylato)hydroxy aluminum, in 
embodiments of the present invention enable, for example, toners with 
rapid and stable triboelectric charging characteristics, and improved 
admix characteristics. Also, the aforementioned toner compositions usually 
contain a colorant component comprised of, for example, carbon black, 
magnetites, or mixtures thereof, color pigments or dyes, and more 
specifically, cyan, magenta, yellow, blue, green, red, or brown pigments, 
or mixtures thereof thereby providing for the development and generation 
of black and/or colored images. The toner and developer compositions of 
the present invention can be selected for electrophotographic, especially 
xerographic, imaging and printing processes, including color processes. 
Toners with negative charge additives are known, reference for example U.S. 
Pat. Nos. 4,411,974 and 4,206,064, the disclosures of which are totally 
incorporated herein by reference. The '974 patent discloses negatively 
charged toner compositions comprised of resins, pigment particles, and as 
a charge enhancing additive ortho-halophenyl carboxylic acids. Similarly, 
there are disclosed in the '064 patent toner compositions with chromium, 
cobalt, and nickel complexes of salicylic acid as negative charge 
enhancing additives. In U.S. Pat. No. 4,845,003, there are illustrated 
negatively charged toners with certain aluminum salt charge additives. 
More specifically, this patent discloses as charge additives aluminum 
complexes comprised of two or three hydroxybenzoic acid ligands bonded to 
a central aluminum ion. A disadvantage of some of these charge additives 
is their thermal instability, that is they often break down during the 
thermal extrusion process of the toner manufacturing cycle. Another 
disadvantage is that some of these additives are colored which can render 
them unsuitable for use in nonblack toners. A fast rate of triboelectric 
charging is particularly crucial for high speed xerographic machines 
since, for example, these machines consume toner rapidly, and fresh toner 
has to be constantly added. The added uncharged toners, therefore, must 
charge up to their equilibrium triboelectric charge level rapidly to 
ensure no interruption in the xerographic imaging or printing operation. 
Many of these and other disadvantages are eliminated, or substantially 
eliminated with the metal salt charge additives of the present invention, 
while maintaining the rapid charging or admix,, necessary for high speed 
xerographic machines. 
Developer compositions with charge enhancing additives, which impart a 
positive charge to the toner particles, are also known. Thus, for example, 
there is described in U.S. Pat. Nos. 3,893,935 the use of quaternary 
ammonium salts as charge control agents for electrostatic toner 
compositions; 4,221,856 which discloses electrophotographic toners 
containing resin compatible quaternary ammonium compounds in which at 
least two R radicals are hydrocarbons having from 8 to about 22 carbon 
atoms, and each other R is a hydrogen or hydrocarbon radical with from 1 
to about 8 carbon atoms, and A is an anion, for example sulfate, 
sulfonate, nitrate, borate, chlorate, and the halogens such as iodide, 
chloride and bromide, reference the Abstract of the Disclosure and column 
3; a similar teaching is presented in U.S. Pat. No. 4,312,933 which is a 
division of U.S. Pat. No. 4,291,111; similar teachings are presented in 
U.S. Pat. No. 4,291,112 wherein A is an anion including, for example, 
sulfate, sulfonate, nitrate, borate, chlorate, and the halogens; U.S. Pat. 
No. 4,338,390, the disclosure of which is totally incorporated herein by 
reference, discloses developer compositions containing as charge enhancing 
additives organic sulfate and sulfonates, which additives can impart a 
positive charge to the toner composition; U.S. Pat. No. 4,298,672, the 
disclosure of which is totally incorporated herein by reference, discloses 
positively charged toner compositions with resins and pigment particles, 
and as charge enhancing additives alkyl pyridinium compounds. 
Illustrated in copending patent application U.S. Ser. No. 894,688 filed 
Jun. 5, 1992 are toner compositions comprised of polymer resins, colorants 
comprised of color pigment particles or dye molecules, and certain metal 
complex charge additives derived from the reaction of a mixture of a 
hydroxybenzoic acid and a base with a metal ion in the presence of an 
excess of a hydroxyphenol. Also, in copending patent applications U.S. 
Ser. No. 898,610 filed Jun. 15, 199, and U.S. Ser. No. 885,589 filed May 
19 is disclosed a negatively charged toner composition comprised of resin 
particles, colorants, optional surface additives, and a dihydroxyaryl 
sulfone charge enhancing additive, or an unsymmetrical hydroxyaryl sulfone 
charge enhancing additive obtained from the condensation of sulfuric acid 
with a molar equivalent of a phenol, followed by condensation with a 
second phenol, or from the condensation of an aromatic sulfonic acid with 
a phenol; and a negatively charged toner composition comprised of resin 
particles, pigment particles, and a hydrotalcite charge enhancing 
additive. 
Although many charge enhancing additives are known, there continues to be a 
need for toners with certain charge enhancing additives thus enabling many 
of the advantages illustrated herein. There is also a need for negative 
charge enhancing additives which are useful for incorporation into black 
and colored toner compositions and which can be utilized for developing 
positive electrostatic latent images. Moreover, there is a need for 
colored toner compositions containing charge enhancing additives which do 
not interfere with the color quality of the colorants present in the 
toners. Another need relates to the provision of toner compositions with 
certain charge enhancing additives, which toners in embodiments thereof 
possess substantially stable triboelectric charge levels, and display 
acceptable rates of triboelectric charging characteristics. Furthermore, 
there is also a need for toner compositions with certain charge enhancing 
additives which possess excellent dispersibility characteristics in toner 
resins, and can, therefore, form stable dispersions in toner compositions 
thereof. There is also a need for negatively charged black and colored 
toner compositions that are useful for incorporation into various imaging 
processes, inclusive of color xerography, as illustrated in U.S. Pat. No. 
4,078,929, the disclosure of which is totally incorporated herein by 
reference; laser printers; and additionally a need for toner compositions 
useful in imaging apparatuses having incorporated therein layered 
photoresponsive imaging members, such as the members illustrated in U.S. 
Pat. No. 4,265,990, the disclosure of which is totally incorporated herein 
by reference. Also, there is a need for negatively charged toner 
compositions which have desirable triboelectric charge levels of, for 
example, from between about -10 to about -40 microcoulombs per gram, and 
preferably from about -15 to about -25 microcoulombs per gram, and 
triboelectric charging rates of less about 120 seconds, and preferably 
less than 60 seconds as measured by standard charge spectrograph methods 
when the toners are frictionally charged against suitable carrier 
particles via conventional roll milling techniques. The concentrations of 
the charge additives that can be selected for the toner compositions 
generally range from about 0.05 weight percent to about 10 weight percent, 
depending on whether the charge additive is utilized as a surface additive 
or as a dispersion in the bulk of the toner. The effective concentrations 
of toner in the developer, that is toner and carrier particles, are for 
example from about 0.5 to about 10 weight percent, and preferably from 
about 1 to about 3 weight percent. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide toner and developer 
compositions with negative charge enhancing additives. 
In another object of the present invention there are provided negatively 
charged toner compositions useful for the development of electrostatic 
latent images including color images, and useful in hybrid scavengeless, 
discharge area development, inductive magnetic brush, conductive magnetic 
brush, single component magnetic brush, and the like. 
A further object is to provide simple and cost effective processes for the 
preparation of metal complex charge enhancing additives. 
Also, in another object of the present invention there are provided toners 
with rapid or improved admix charging characteristics. 
These and other objects of the present invention may be accomplished in 
embodiments thereof by providing toner compositions comprised of a polymer 
or polymer resins, colorants comprised of color pigment particles or dye 
molecules, and certain metal complex charge additives. More specifically, 
the present invention in embodiments is directed to toner compositions 
comprised of resin particles, pigment particles, and an aluminum metal 
negative charge enhancing additive or mixtures thereof of the formulas 
##STR1## 
Also, in embodiments toners with aluminum metal negative charge additives 
of the formula are envisioned. 
##STR2## 
Examples of specific charge additives include 
bis(xanthene-9-carboxylato)hydroxy aluminum, 
bis(coumarin-3-carboxylato)hydroxy aluminum, 
(coumarin-3-carboxylato)(xanthene-9-carboxylato)hydroxy aluminum, and the 
like. The aforementioned coumarin xanthene can be prepared as illustrated 
herein, for example, by reacting coumarin and xanthene carboxylic and 
mixture with an aqueous aluminum inorganic salt; ratio of, for example, 
1:1:1. 
The aforementioned charge additives can be incorporated into the toner, may 
be present in effective amounts such as indicated herein like, for example 
from about 0.05 to about 10 weight percent on the toner surface, or may be 
present on toner surface additives, such as colloidal silica, titanium 
oxide (TiO.sub.2) particles, and the like. Advantages of rapid 
triboelectric charging characteristics of generally less than 120 seconds, 
and preferably less than 60 seconds, such as about 15 to 30 seconds, in 
embodiments as measured by the standard charge spectrograph methods when 
the toners are frictionally charged against carrier particles by known 
conventional roll mixing methods, appropriate triboelectric charge levels, 
and the like can be achieved with many of the aforementioned toners of the 
present invention. In another embodiment of the present invention, there 
are provided, subsequent to known micronization and classification, toner 
particles with a volume average diameter of from about 5 to about 20 
microns. 
The aluminum charge additives of the present invention can be prepared by 
the reaction dissolution of a xanthene, such as xanthene-9-carboxylic 
acid, and/or a coumarin carboxylic acid, such as coumarin-3-carboxylic 
acid dissolved with a known base, like sodium hydroxide, or with an 
aqueous aluminum inorganic salt solution such as aluminum sulfate or 
aluminum chloride. The ratio of the reactants is such that there are, for 
example, two molecules of acid for every aluminum atom. The reaction can 
be accomplished at temperatures ranging from about 60.degree. C. to 
95.degree. C. The resulting product precipitate is filtered and washed 
with, for example, clean water and dried in, for example, a heated 
laboratory oven. The product can be identified by a number of know methods 
such as infrared analysis. 
The toner compositions of the present invention can be prepared by a number 
of known methods such as admixing and heating polymer resins such as 
styrene butadiene copolymers, colorants such as color pigment particles or 
dye compounds, and the aforementioned metal complex charge enhancing 
additive, or mixtures of charge additives in a concentration, preferably 
ranging from about 0.5 percent to about 10 percent, in a toner extrusion 
device, such as the ZSK53 available from Werner Pfleiderer, and removing 
the resulting toner composition from the device. Subsequent to cooling, 
the toner composition is subjected to grinding utilizing, for example, a 
Sturtevant micronizer for the purpose of achieving toner particles with a 
volume average diameter of from about 5 to about 25 microns, and 
preferably from about 5 to about 12 microns, which diameters are 
determined by a Coulter Counter. Subsequently, the toner compositions can 
be classified utilizing, for example, a Donaldson Model B classifier for 
the purpose of removing unwanted fine toner particles. 
Illustrative examples of suitable toner resins selected for the toner and 
developer compositions of the present invention include vinyl polymers 
such as styrene polymers, styrene acrylates, styrene methacrylates, 
styrene butadienes, acrylonitrile polymers, vinyl ether polymers, acrylate 
and methacrylate polymers; epoxy polymers; polyurethanes; polyamides and 
polyimides; polyesters; mixtures thereof; and the like. The polymer resins 
selected for the toner compositions of the present invention include 
homopolymers or copolymers of two or more monomers. Furthermore, the above 
mentioned polymer resins may also be crosslinked depending on the desired 
toner properties. Illustrative vinyl monomer components in the vinyl 
polymers include styrene, substituted styrenes such as methyl styrene, 
chlorostyrene, methyl acrylate and methacrylate, ethyl acrylate and 
methacrylate, propyl acrylate and methacrylate, butyl acrylate and 
methacrylate, pentyl acrylate and methacrylate, butadiene, vinyl chloride, 
acrylonitrile, acrylamide, alkyl vinyl ether and the like. Illustrative 
examples of the dicarboxylic acid units in the polyester resins suitable 
for use in the toner compositions of the present invention include 
phthalic acid, terephthalic acid, isophthalic acid, succinic acid, 
glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, 
sebacic acid, maleic acid, fumaric acid, dimethyl glutaric acid, 
bromoadipic acids, dichloroglutaric acids, and the like; while 
illustrative examples of the diol units in the polyester resins include 
ethanediol, propanediols, butanediols, pentanediols, pinacol, 
cyclopentanediols, hydrobenzoin, bis(hydroxyphenyl)alkanes, 
dihydroxybiphenyl, substituted dihydroxybiphenyls, and the like. 
As one toner resin, there can be selected polyester resins derived from a 
dicarboxylic acid and a diphenol, which resins are illustrated in U.S. 
Pat. No. 3,590,000, the disclosure of which is totally incorporated herein 
by reference; polyester resins obtained from the reaction of bisphenol A 
and propylene oxide, followed by the reaction of the resulting product 
with fumaric acid, and branched polyester resins resulting from the 
reaction of dimethylterephthalate with 1,3-butanediol, 1,2-propanediol, 
and pentanetriol. Further, low melting polyesters, especially those 
prepared by reactive extrusion reference U.S. Ser. No. 814,641 filed Dec. 
30, 1991 and U.S. Ser. No. 814,782 filed Dec. 30, 1991, the disclosures of 
which are totally incorporated herein by reference, can be selected as 
toner resins. Other specific toner resins include styrene methacrylate 
copolymers, and styrene butadiene copolymers; PLIOLITES.RTM.; suspension 
polymerized styrene butadienes, reference U.S. Pat. No. 4,558,108, the 
disclosure of which is totally incorporated herein by reference. Also, 
waxes with a molecular weight of from about 1,000 to about 7,000, such as 
polyethylene, polypropylene, and paraffin waxes, can be included in or on 
the toner compositions as fuser roll release agents. 
The polymer resins are present in a sufficient, but effective amount, for 
example from about 30 to about 95 weight percent. Thus, when 1 percent by 
weight of the charge enhancing additive is present, and 10 percent by 
weight of colorant, such as carbon black or color pigment, is contained 
therein, about 89 percent by weight of resin is selected. Also, the charge 
enhancing additive of the present invention may be applied as a surface 
coating on the toner particles. When used as a coating, the charge 
enhancing additive of the present invention is present in an amount of 
from about 0.05 weight percent to about 5 weight percent, and preferably 
from about 0.1 weight percent to about 1.0 weight percent. 
Numerous well known suitable color pigments or dyes can be selected as the 
colorant for the toner compositions including, for example, carbon black, 
like REGAL 330.RTM., nigrosine dye, metal phthalocyanines, aniline blue, 
magnetite, or mixtures thereof. The colorant, which is preferably carbon 
black or other color pigments, should be present in a sufficient amount to 
render the toner composition with a sufficiently high color intensity. 
Generally, the colorants are present in effective amounts of from about 
0.1 weight percent to about 20 weight percent, and preferably from about 1 
to about 10 weight percent based on the total weight of the toner 
composition; however, lesser or greater amounts of colorant may be 
selected. 
When the colorants are comprised of magnetites or a mixture of magnetites 
and color pigment particles, thereby enabling single component toners and 
toners for magnetic ink character recognition (MICR) applications in some 
instances, which magnetites are a mixture of iron oxides (FeO.Fe.sub.2 
O.sub.3), including those commercially available as MAPICO BLACK.RTM., 
they are present in the toner composition in an amount of from about 5 
weight percent to about 70 weight percent, and preferably in an amount of 
from about 10 weight percent to about 50 weight percent. Mixtures of 
carbon black and magnetite with from about 1 to about 15 weight percent of 
carbon black, and preferably from about 2 to about 6 weight percent of 
carbon black, and magnetite, such as MAPICO BLACK.RTM., in an amount of, 
for example, from about 5 to about 70, and preferably from about 10 to 
about 50 weight percent can be selected for black toner compositions of 
the present invention. 
There can also be blended with the toner compositions of the present 
invention external additives including flow aid additives, which additives 
are usually present on the surface thereof. Examples of these additives 
include colloidal silicas such as AEROSIL.RTM., metal salts and metal 
salts of fatty acids inclusive of zinc stearate, aluminum oxides, 
especially Al.sub.2 O.sub.3, tin oxide, cerium oxides, titanium oxides, 
and mixtures thereof, which additives are generally present in an amount 
of from about 0.1 percent by weight to about 5 percent by weight, and 
preferably are present in an amount of from about 0.5 percent by weight to 
about 2 percent by weight. Several of the aforementioned additives are 
illustrated in U.S. Pat. Nos. 3,590,000 and 3,800,588, the disclosures of 
which are totally incorporated herein by reference. 
With further respect to the present invention, colloidal silicas, such as 
AEROSIL.RTM., can be surface treated with the metal charge additives of 
the present invention illustrated herein in an amount of from about 1 to 
about 50 weight percent and preferably 10 weight percent to about 25 
weight percent followed by the addition thereof to the toners in an amount 
of from 0.1 to 10 and preferably 0.1 to 5 weight percent. 
Also, there can be included in the toner compositions of the present 
invention as indicated herein low molecular weight waxes, such as 
polypropylenes and polyethylenes, commercially available from Allied 
Chemical and Petrolite Corporation, EPOLENE N-15.TM. commercially 
available from Eastman Chemical Products, Inc., VISCOL 550-P.TM. a low 
weight average molecular weight polypropylene available from Sanyo Kasei 
K. K., and similar materials. The commercially available polyethylenes 
selected have a molecular weight of from about 1,000 to about 1,500, while 
the commercially available polypropylenes utilized for the toner 
compositions of the present invention are believed to have a molecular 
weight of from about 4,000 to about 7,000. Many of the polyethylene and 
polypropylene compositions useful in the present invention are illustrated 
in British Patent No. 1,442,835, the disclosure of which is totally 
incorporated herein by reference. These low molecular weight wax materials 
are present in the toner composition of the present invention in various 
amounts, however, generally these waxes are present in the toner 
composition in an amount of from about 1 percent by weight to about 15 
percent by weight, and preferably in an amount of from about 2 weight 
percent to about 10 weight percent. 
Included within the scope of the present invention are colored toner and 
developer compositions comprised of toner resins, optional carrier 
particles, the charge enhancing additives illustrated herein, and as 
colorants red, blue, green, brown, magenta, cyan and/or yellow dyes or 
color pigments, as well as mixtures thereof. More specifically, with 
regard to the generation of color images utilizing a developer composition 
with the aluminum charge enhancing additives of the present invention, 
illustrative examples of magenta materials that may be selected as 
colorants include, for example 2,9-dimethyl-substituted quinacridone and 
anthraquinone dye identified in the Color Index as Cl 60710, Cl Dispersed 
Red 15, diazo dye identified in the Color Index as Cl 26050, Cl Solvent 
Red 19, and the like. Illustrative examples of cyan materials that may be 
used as colorants include copper phthalocyanine, x-copper phthalocyanine 
pigment listed in the Color Index as Cl 74160, Cl Pigment Blue, and 
Anthrathrene Blue, identified in the Color Index as Cl 69810, Special Blue 
X-2137, and the like; while illustrative examples of yellow pigments that 
may be selected are diarylide yellow 3,3-dichlorobenzidene 
acetoacetanilides, a monoazo pigment identified in the Color Index as Cl 
12700, Cl Solvent Yellow 16, a nitrophenyl amine sulfonamide identified in 
the Color Index as Foron Yellow SE/GLN, Cl Dispersed Yellow 33, 
2,5-dimethoxy-4-sulfonanilide phenylazo-4'-chloro-2,5-dimethoxy 
acetoacetanilide, and Permanent Yellow FGL. The aforementioned colorants 
are incorporated into the toner composition in various suitable effective 
amounts. In embodiments, these colorants are present in the toner 
composition in an amount of from about 1 percent by weight to about 15 
percent by weight based on the total weight of the toner. 
For the formulation of developer compositions, there are mixed with the 
toner particles carrier components, particularly those that are capable of 
triboelectrically assuming an opposite polarity to that of the toner 
composition. Accordingly, the carrier particles of the present invention 
are selected to be those that would render the toner particles negatively 
charged while acquiring a positive charge polarity themselves via 
frictional charging against the toner particles of the present invention. 
The opposite charge polarities of the carrier and toner particles of the 
developer composition thus ensure the toner particles to adhere to and 
surround the carrier particles. Illustrative examples of carrier particles 
include iron powder, steel, nickel, iron, ferrites, including copper zinc 
ferrites, nickel zinc ferrites, and the like. Additionally, there can be 
selected as carrier particles nickel berry carriers as illustrated in U.S. 
Pat. No. 3,847,604, the disclosure of which is totally incorporated herein 
by reference. The selected carrier particles can be used with or without a 
coating, the coating generally containing terpolymers of styrene, 
methylmethacrylate, and a silane, such as triethoxysilane, reference U.S. 
Pat. Nos. 3,526,533 and 3,467,634, the disclosures of which are totally 
incorporated herein by reference; polymethyl methacrylates; other known 
coatings; and the like. The carrier particles may also include in the 
coating, which coating can be present in one embodiment in an amount of 
from about 0.1 to about 3 weight percent, conductive substances such as 
carbon black in an amount of from about 5 to about 30 percent by weight. 
Polymer coatings not in close proximity in the triboelectric series can 
also be selected, reference U.S. Pat. Nos. 4,937,166 and 4,935,326, the 
disclosures of which are totally incorporated herein by reference, 
including for example KYNAR.RTM. and polymethylmethacrylate mixtures 
(40/60). Coating weights can vary as indicated herein; generally, however, 
from about 0.3 to about 2, and preferably from about 0.5 to about 1.5 
weight percent coating weight is selected. 
Furthermore, the diameter of the carrier particles, preferably spherical in 
shape, is generally from about 50 to about 1,000 microns, and preferably 
from between about 80 and 200 microns in volume average diameter thereby 
permitting them, for example, to possess sufficient density and inertia to 
avoid adherence to the electrostatic images during the development 
process. The carrier component can be mixed with the toner composition in 
various suitable combinations, such as about 1 to 5 parts of toner to 
about 100 parts to about 200 parts by weight of carrier. 
The toner composition of the present invention can be prepared by a number 
of known methods including extrusion melt blending the toner resins, 
colorants, and the metal charge enhancing additive of the present 
invention as indicated herein, followed by mechanical attrition and 
classification. Other methods include those well known in the art such as 
spray drying, melt dispersion, extrusion processing, dispersion 
polymerization, and suspension polymerization. Also, as indicated herein 
the toner composition without the charge enhancing additive can be first 
prepared, followed by addition of the charge enhancing additives and other 
optional surface additives, or the charge enhancing additive-treated 
surface additives such as colloidal silicas. Further, other methods of 
preparation for the toner are as illustrated herein. 
The toner and developer compositions of the present invention may be 
selected for use in electrostatographic imaging apparatuses containing 
therein conventional photoreceptors providing that they are capable of 
forming positive electrostatic latent images relative to the triboelectric 
charge polarity of the toners. 
The toners of the present invention are usually jetted and classified 
subsequent to preparation to enable toner particles with a preferred 
volume average diameter of from about 5 to about 25 microns, and more 
preferably from about 5 to about 12 microns. The triboelectric charging 
rates for the toners of the present invention are preferably less than 120 
seconds, more specifically less than 60 seconds, and from 15 to about 30 
seconds in embodiments thereof as determined by the known charge 
spectrograph method as described hereinbefore. These toner compositions 
with rapid rates of triboelectric charging characteristics enable, for 
example, the development of images in electrophotographic imaging 
apparatuses, which images have substantially no background deposits 
thereon, even at high toner dispensing rates in some instances, for 
instance exceeding 20 grams per minute; and further, such toner 
compositions can be selected for high speed electrophotographic 
apparatuses, that is those exceeding 50 copies per minute.

The following Examples are being supplied to further illustrate various 
embodiments of the present invention, it being noted that these Examples 
are intended to illustrate and not limit the scope of the present 
invention. Comparative Examples and other Examples are also presented. 
EXAMPLE I 
Synthesis of Bis(xanthene-9-carboxylato)hydroxy Aluminum 
To a first solution of 1.33 grams (0.033 mole) of NaOH in 75 milliliters of 
water were added 5 grams (0.022 mole) of xanthene-9-carboxylic acid. The 
resulting mixture was heated to approximately 60.degree. C. to dissolve 
the acid. A second solution was prepared by dissolving 3.68 grams (0.0055 
mole) of aluminum sulfate, Al.sub.2 (SO.sub.4).sub.3.18H.sub.2 O, in 75 
milliliters of water with heating to 60.degree. C. The former solution 
containing the sodium salt of the acid was added rapidly and dropwise into 
the aluminum sulfate salt solution with stirring. A precipitate forms 
immediately. When the addition was completed, the reaction mixture was 
stirred an additional 5 to 10 minutes at 60.degree. C. and then cooled to 
room temperature, about 25.degree. C. The mixture was then filtered and 
the collected solid product was washed with water until the acidity of the 
used wash water was about 5.5 (distilled water measured 6.0). The product 
was dried for 16 hours in a vacuum oven at 120.degree. F. to afford 4.21 
grams (0.0085 mole, 76.9 percent of theory) of a white powder. When a 
sample of the product obtained was analyzed for water by Karl-Fischer 
titration after drying for an additional 12 hours at 100.degree. C. in a 
vacuum, the sample contained 0.72 percent weight of water. The theoretical 
value calculated for a one mole of water for the product is 3.65 percent 
weight of water. 
Infrared spectra of the above product indicated the presence of an aluminum 
carboxylate (Al-COO-) bond not present in the starting acid and a decrease 
of the acid peaks characteristic of the starting acid. There also appears 
a shoulder on the hydroxyl band (3,675 cm.sup.-1 region) that appears to 
be attributed to an Al-OH band. 
Elemental Analysis for C.sub.28 H.sub.17 O.sub.7 Al: Calculated: C, 68.2; 
H, 3.49; Al, 5.48. Found: C, 66.5; H, 3.83; Al, 4.62. 
EXAMPLE II 
Synthesis of Bis(coumarin-3-carboxylato)hydroxy Aluminum 
To a solution of 1.58 grams (0.0395 mole) of NaOH in 100 milliliters of 
water were added 5 grams (0.026 mole) of coumarin-3-carboxylic acid and an 
additional 100 milliliters of water. The resulting mixture was heated to 
approximately 90.degree. C. to dissolve the acid. A second solution was 
prepared by dissolving 4.38 grams (0.0066 mole) of aluminum sulfate 
Al.sub.2 (SO.sub.4).sub.3.18H.sub.2 O in 100 milliliters of water with 
heating to approximately 90.degree. C. The former solution containing the 
sodium salt of the acid was added rapidly and dropwise into the latter 
aluminum sulfate salt solution with stirring. A precipitate forms 
immediately. When the addition was completed, the reaction mixture was 
stirred an additional 5 to 10 minutes at 90.degree. C. and then cooled to 
room temperature, about 25.degree. C. The mixture was then filtered and 
the collected solid product was washed with water until the acidity of the 
used wash water was about 5.5 (distilled water measured about 6.0). The 
product was dried for 16 hours in a vacuum oven at 120.degree. F. to 
afford 4.74 grams (0.011 mole, 83 percent of theory) of a pale yellow 
powder. The Karl-Fischer analysis of the product after drying in a vacuum 
oven indicated that there was 3.16 percent water in the product. One mole 
of water in the product would equal 4.26 percent. 
Infrared spectra of the above product indicated the presence of an aluminum 
carboxylate (Al-COO-) bond not present in the starting acid and a decrease 
of the acid peaks characteristic of the starting material, 
coumarin-3-carboxylic acid. There also appears a shoulder on the hydroxyl 
band (3,633 cm.sup.-1 region) that could be attributed to an Al-OH band. 
Elemental Analysis for C.sub.20 H.sub.11 O.sub.9 Al: Calculated: C, 56.9; 
H, 2.63; Al, 6.39. Found: C, 54.7; H, 2.43; Al, 4.53. 
EXAMPLE III 
There was prepared in an extrusion device, available as ZSK-28 from Werner 
Pfleiderer, a toner composition comprised of 95.5 parts of 
styrene/butadiene copolymer and 4.5 parts of PV FAST BLUE.TM. pigment 
obtained from Hoechst Celanese by melt blending these components in the 
extruder, followed by micronization, and air classification to yield toner 
sized particles of 10 microns in volume average diameter as determined by 
a Coulter Counter. A developer was prepared by selecting 3 parts of the 
toner and blending it with 100 parts of Hoeganoes Anchor steel core with a 
particle diameter range of from about 75 to about 150 microns, available 
from Hoeganoes Company, as the carrier and roll milling for a period of 
about 30 minutes which resulted in a developer with a toner exhibiting a 
triboelectric charge of -8.2 microcoulombs per gram as determined by the 
known Faraday Cage method. A charge spectrograph analysis of the developer 
measured at 125 volts/centimeter resulted in a bimodal charge distribution 
through 60 seconds indicating that the developer without charge control 
additive admixed in greater than 1 minute. A second developer was prepared 
by selecting 3 parts of the above toner and blending it with 100 parts of 
carrier particles that were prepared as follows: Hoeganoes Anchor steel 
core with a particle diameter range of from about 75 to about 150 microns, 
available from Hoeganoes Company, was solution coated with 1 part by 
weight of a coating comprising 20 parts by weight of VULCAN.TM. carbon 
black, available from Cabot Corporation, homogeneously dispersed in 80 
parts by weight of polymethylmethacrylate, which coating was solution 
coated from toluene. Roll milling for a period of about 30 minutes 
resulted in a developer with a toner exhibiting a triboelectric charge of 
-7.0 microcoulombs per gram. A charge spectrograph analysis of the 
developer measured at 125 volts/centimeter resulted in a bimodal charge 
distribution through 60 seconds indicating that the developer without 
charge control additive admixed in greater than 1 minute. 
EXAMPLE IV 
A toner was prepared as follows: 94.5 parts of styrene/butadiene copolymer, 
4.5 parts of PV FAST BLUE.TM. pigment from Hoechst Celanese and 1 part of 
the hydroxy aluminum compound of Example I were melt blended in an 
extruder followed by micronization and air classification to yield toner 
sized particles of 10 microns in volume average diameter. A developer was 
prepared by blending 3 parts of the toner with the coated carrier of 
Example III and roll milling for a period of about 30 minutes which 
resulted in a developer with a toner exhibiting a triboelectric charge of 
-10.19 microcoulombs per gram. A charge spectrograph analysis of the 
developer measured at 125 volts/centimeter resulted in a 15 to 30 second 
admix, evidencing an improvement in admix performance over the same toner 
with no charge control additive. 
EXAMPLE V 
A toner was prepared as in Example IV except 3 parts of the hydroxy 
aluminum compound prepared in Example I was used. A developer was prepared 
by repeating the process of Example IV. The resulting developer exhibited 
a triboelectric charge of -12.99 microcoulombs per gram. A charge 
spectrograph analysis of the developer measured at 125 volts/centimeter 
resulted in a 15 to 30 second admix. 
EXAMPLE VI 
A toner was prepared by repeating the process of Example IV except that 1 
part of the hydroxy aluminum compound as prepared in Example II was 
selected as the charge additive. A developer with this toner was prepared 
by repeating the process of Example IV except the bare steel carrier as in 
Example III was used instead of the coated carrier, resulting in a 
triboelectric charge of -15.71 microcoulombs per gram. A charge 
spectrograph analysis of the developer measured at 125 volts/centimeter 
resulted in a 15 to 30 second admix. 
Toners with a charge additive like (coumarin-3-carboxylato) 
(xanthene-9-carboxylato) hydroxy aluminum, and developers thereof were 
prepared by substantially repeating the processes of the above Examples 
and substantially similar results were obtained. 
Other modifications of the present invention may occur to those skilled in 
the art subsequent to a review of the present application. The 
aforementioned modifications, including equivalents thereof, are intended 
to be included within the scope of the present invention.