Toner compositions with conductive colored magnetic particles

A toner composition comprised of resin particles, pigments, and a colored highly conductive magnetic composition comprised of a core comprised of a metal, and thereover a coating comprised of a lightly colored metal selected from the group consisting of copper, silver, cobalt, tin, gold, manganese, titanium, magnesium, vanadium, chromium, zinc, cadmium, indium, rhodium, niobium, platinum and aluminum, and in contact with the lightly colored metal a top coating comprised of a substantially colorless metal halide.

BACKGROUND OF THE INVENTION 
The present invention is generally directed to conductive magnetic 
compositions and process thereof, and more specifically the present 
invention is directed to lightly colored conductive magnetic compositions, 
process thereof, and processes for the preparation of colored toner 
compositions, and inductive magnetic developers. In one embodiment, the 
present invention is related to magnetic particles with an average volume 
diameter of from about 0.1 micron to about 25 microns and more preferably 
from about 0.5 micron to about 6 microns, comprised of a core comprised of 
a magnetic particle, coated thereover with a lightly colored metal. In 
another embodiment, the present invention is related to magnetic particles 
with an average particle diameter size of from about 0.1 micron to about 
25 microns and more preferably from about 0.5 micron to about 6 microns as 
measured by a Coulter Counter, which particles are comprised of a core 
comprised of a magnetic particle coated thereover with a lightly colored 
metal and overcoated thereover with a colorless metal halide, or oxide. 
Toner compositions comprised of resin particles, and the aforementioned 
magnetic particles are also encompassed by the present invention. In 
another embodiment, the present invention is related to a process for the 
preparation of magnetic particles comprised of a metal coated with another 
metal of a lightness value of from about 0 to about 60 units and 
preferably from about 0 to 30 units as measured by the Match-Scan II 
colorspectrometer available from Vidan Corporation. Moreover, in another 
embodiment, the colored metal coating is a light orange, brown, red, blue, 
or yellow color and displays a chroma of from about 0 to 40 units and a 
hue of from about 0 to 40 units as measured by the Match-Scan II 
colorspectrometer available from Vidan Corporation. In another embodiment, 
the present invention is related to a process for the preparation of 
lightly colored conductive magnetic particles of from about 0.1 micron to 
about 25 microns and more preferably from about 0.5 micron to about 6 
microns, comprised of a core comprised of a metal; thereover a coating of 
a lightly colored metal formed by an in situ electrodeless electrochemical 
oxidation-reduction reaction between the magnetic particle surface and a 
solution of a soluble metal salt of the lightly colored metal ion. In yet 
another embodiment, the present invention is related to a process of 
preparing lightly colored conductive magnetic particles comprised of a 
core comprised of a metal; thereover a coating of a lightly colored metal 
formed by an in situ electrodeless electrochemical oxidation-reduction 
reaction between the magnetic particle surface and a solution of a soluble 
metal salt of the lightly colored metal ion; and thereover an overcoating 
of metal halide or metal oxide formed by an insitu oxidation reaction 
between the magnetic particle surface with a halide such as lodine or 
oxide such as peroxide. In another embodiment, the present invention is 
related to a process for the preparation of conductive magnetic particles 
wherein the overcoating of metal halide displays a lightness values of 
from about 0 to about 60 units and preferably from about 0 to 43 units; a 
chroma of from about 0 to 40 units and a hue of from about 0 to 40 units 
as measured by the Match-Scan II colorspectrometer available from Vidan 
Corporation. In another embodiment, the present invention relates to 
conductive lightly colored magnetic particles with conductivities of from 
about 0.1 (ohm-cm).sup.-1 to about 10.sup.-4 (ohm-cm).sup.-1. Another 
embodiment of the present invention relates to the use of the 
aforementioned lightly colored conductive magnetic particles in inductive 
magnetic developer compositions useful for ionographic processes. Also, in 
another embodiment the present invention relates to the use of these 
lightly colored conductive magnetic particles in magnetic colored toner 
compositions useful for xerographic processes. 
The primary functions of the magnetic core particle is to provide 
appropriate magnetic properties such as from about 30 to about 120 emu per 
gram and more preferably from about 60 emu per gram to about 100 emu per 
gram. The primary function of the lightly colored metallic overcoating 
layer is to provide the desired conductivity of from about 10.sup.-4 
(ohm-cm).sup.-1 to about 10.sup.-8 (ohm-cm).sup.-1, and in particular, to 
provide a light color to the magnetic particle with lightness values of 
from about 0 to about 60 units and preferably from about 0 to 40 units and 
more perferably from about 0 to about 6 units as measured by the 
Match-Scan II colorspectrometer available from Vidan Corporation. 
Effective metallic overcoating of the magnetic particle enables magnetic 
particles of very low tinctorial strength, such as a chroma of from about 
0 to 40 units and a hue of from about 0 to 40 units as measured by the 
Match-Scan II colorspectrometer available from Vidan Corporation, enabling 
in embodiments the incorporation of these magnetic particles into colored 
toner compositions with complete, or substantially complete passivation of 
the coloring perturbation of the magnetic material on the colored toner 
composition. Coating of the core metal particle would lead to 
substantially the same, or higher conductivity for the coated magnetic 
particles enabling in one embodiment the incorporation of these magnetic 
particles into colored toner compositions where conductivity of from about 
10.sup.-4 (ohm-cm).sup.-1 to about 10.sup.-8 (ohm-cm).sup.-1 is important 
for use in electrographic technologies. The primary function of the 
metallic halide or oxide overcoating layer is to provide the desired high 
conductivity of from about 0.1 (ohm-cm).sup.-1 to about 10.sup.-4 
(ohm-cm).sup.-1, and in particular, to provide a light color with 
lightness of from about 0 to about 60 units, chroma of about 0 to about 40 
units, and hue of about 0 to about 40 units, and preferably a colorless 
magnetic particle with lightness, chroma and hue of 10 units as measured 
by the Match-Scan II spectrometer. Effective metallic halide or oxide 
overcoating of the magnetic composite particle comprised of a metal coated 
with the aforementioned lightly colored metal enables magnetic particles 
of low tinctorial strength enabling in one embodiment the incorporation of 
these magnetic particles into highly conductive colored toner compositions 
with conductivity of from about 0.1 (ohm-cm).sup.- to about 10.sup.-4 
(ohm-cm).sup.-1, and particularly useful in known inductive ionographic 
imaging systems, and technologies. 
For a number of ionographic and electrophotographic imaging methods for 
printing and copying applications, it is desirable that the toner 
particles contain a magnetic material. Typical magnetic materials with 
appropriate magnetic properties for use in the preparation of such toner 
particles include metal powders of iron, cobalt, and nickel, metal oxide 
powders of iron or chromium, and ferrite particles of particle size in the 
range of about 20 nanometers to about 10 microns. Many of these particles, 
however, exhibit relatively poor electrical conductivity, such as from 
about 10.sup.-7 ohm-cm to about 10.sup.-14 ohm-cm, resulting in poor 
developability or no developability when employed in electrophotographic 
devices. Relatively higher electrical conductivity of from about 10.sup.-4 
(ohm-cm).sup.-1 to about 10.sup.-8 (ohm-cm).sup.-1 is required for toner 
applications involving single component electrophotographic development 
systems. Additionally, yet even higher electrical conductivity is required 
for inductive signal component developers of from about 0.1 
(ohm-cm).sup.-1 to about 10.sup.-4 (ohm-cm).sup.-1 for some ionographic 
development systems. The poor conductivity of these magnetic materials can 
be overcome by addition of highly conductive carbon black or tin oxide as 
external additives. However, the presence of external additives on 
magnetic pigments of high tinctorial strengths do not adversely affect the 
color quality of the magnetic pigment, other than black, and are of 
inferior color quality. Furthermore, the use of external conductive 
additives may display poor conductivity stability in both ionographic or 
electrographic processes. Furthermore, when carbon black is employed, it 
can restrict the use of such developer compositions to the production of 
black images only, and cannot be satisfactorily applied to the production 
of color images. In addition, many of the magnetic materials that have the 
required magnetic properties and the desired particle size for colored 
developer compositions are also black or darkly colored with relatively 
high tinctorial strength. Thus, these magnetic materials usually cannot be 
applied to the production of colored images, in particular lightly colored 
images, such as red, orange, yellow, green and magenta. Neutral color or 
matched color or lightly colored magnetic particles with suitable magnetic 
properties of from about 60 to about 100 emu per gram, and with 
resistivity of from about 0.1 (ohm-cm).sup.-1 to about 10.sup.-4 
(ohm-cm).sup.-1 are not believed to be known. The conductive lightly 
colored magnetic particle compositions of the present invention, in one 
specific embodiment, can be generated by a direct preparative process 
involving an in situ electrochemical reaction between the surface of a 
core metallic magnetic particle, and a solution of a soluble salt of a 
lightly colored metal to produce an adherent coating metallic layer on the 
magnetic particle surface. In one embodiment, the coated magnetic 
particles are highly conductive, lightly colored with low tinctorial 
strength, and have suitable conductivity to meet all the requirements of 
magnetic toner compositions for color magnetic single component 
electrophotographic devices. Additionally, in another specific embodiment, 
the aforementioned conductive lightly colored magnetic particle comprised 
of a magnetic particle coated with a lightly colored conductive metal can 
be generated by a direct preparative process involving an oxidation 
reaction between the metal coating with a halide, such as iodine or oxide 
such as peroxide, or produce an outer coating of metal halide or metal 
oxide layer on the particle composite surface. In another embodiment, the 
aforementioned overcoated magnetic particles are highly conductive, 
lightly colored with low tinctorial strength, and have suitable 
conductivity to meet all the requirements of an inductive magnetic 
compositions for colored single component ionographic devices. For 
example, in a specific embodiment of this invention, the lightly colored 
magnetic particle is prepared by suspending about 1 mole percent by weight 
of iron metal powder of from about 1 to about 4 microns in an aqueous 
media containing copper(II)(valence of 2)sulfate of from about 0.2 mole 
percent by weight and catalytic amounts of sulfuric acid, effecting a 
metal coating of copper onto the core iron particle via an oxidation 
reduction reaction at a temperature of from about 10.degree. C. to about 
30.degree. C. This aforementioned iron-copper magnetic particle is thus 
comprised of a core comprised of iron metal bound to a coating of copper 
metal resulting in a reddish color displaying a magnetic saturation of 
from about 80 emu per gram to about 85 emu per gram, and conductivity of 
from about 10.sup.-5 (ohm-cm).sup.-1. Subsequently, in another specific 
embodiment, the aforementioned iron-copper metal particle is treated with 
about 0.1 mole percent of iodine effecting an oxidation reaction between 
the outer metal copper coating and resulting in an outer coating of copper 
iodide at a temperature of from about 10.degree. C. to about 30.degree. C. 
This aforementioned magnetic particle is thus comprised of a core 
comprised of iron metal bound to a coating of copper metal and bounded 
thereover an overcoating of copper iodide layer resulting in a light 
reddish color displaying a magnetic saturation of from about 80 emu per 
gram to about 85 emu per gram, and conductivity from about 0.1 
(ohm-cm).sup.-1 to about 10.sup.-4 (ohm-cm).sup.-1. Colored prints with 
chroma values of less than 40 units are considered poor quality to those 
in the art. In prior art magnetic toner compositions, the use of suitable 
magnetic materials displaying magnetic saturations of from about 60 to 
about 100 emu per gram, as well as displaying undesired high lightness 
values of from about 60 to about 100 units mask the effect of the pigment 
lightness, chroma and hue properties when incorporated with resin and 
pigments to obtain toner composition. The masking effect of the magnetic 
particles leads to poor quality colored prints with lightness, chroma and 
hue values of less than 40 units. In order to obtain good quality colored 
prints, it is desirable to use magnetic composites displaying suitable 
magnetic saturation of from about 60 to about 100 emu per gram as well as 
low lightness values of from about 0 to about 60 units, such that when 
incorporated into toner compositions with resins and pigments does not 
affect or perturb the high lightness, chroma and hue properties of the 
pigments, hence, generating good color quality prints with high lightness, 
chroma and hue values greater than 40 units. 
The magnetic particles of this invention, and the toners thereof possess 
many advantages as illustrated herein. For example many prior art magnetic 
particles are coated externally to reduce their tinctorial strengths, but 
are only held statically to the surface and are not physically bound. 
Furthermore, such composites when utilized in the preparation of magnetic 
toners or developers do not retain their coated morphology and the 
external additives are removed partially or substantially from the metal 
particle during the process of the toner preparation yielding dull 
magnetic colored toner images. The magnetic particles, or compositions of 
the present invention in embodiments possess lightly colored metal or 
metal halide coatings bound to the surface and retain this morphology with 
low lightness of from about 0 to about 60 units and low tinctorial 
strengths of chroma values of from about 0 to 40 units and hue values of 
from about 0 to 40 units, and which during the preparation of colored 
magnetic toner compositions do not interfere or perturb the pigment's high 
lightness, chroma and hue, permitting rendering good excellent quality 
with substantially no background deposits, colored prints with high 
lightness, chroma and hue values of from about 60 to about 100 units as 
measured with the Match-Scan II spectrometer available fron Vidan 
Corporation. 
The toner compositions of the present invention can be selected for a 
variety of known reprographic imaging processes including 
electrophotographic, especially xerographic, and ionographic processes. In 
one embodiment, the toner compositions can be selected for pressure fixing 
processes wherein the image is fixed with pressure. Pressure fixing is 
common in ionographic processes in which latent images are generated on a 
dielectric receiver such as silicon carbide, reference U.S. Pat. No. 
4,885,220 (D/87316), entitled Amorphous Silicon Carbide Electroreceptors, 
the disclosure of which is totally incorporated herein by reference. The 
latent images can then be toned with the relatively conductive toner of 
the present invention by inductive single component development, and 
transferred and fixed simultaneously (transfix) in one single step onto 
paper with pressure. Specifically, the toner compositions of the present 
invention can be selected for the commercial Delphax printers, such as the 
Delphax S9000.TM., S6000.TM., S4500.TM., S3000.TM., and Xerox Corporation 
printers such as the 4060.TM. and 4075.TM. wherein, for example, 
transfixing is utilized. In another embodiment, the toner compositions of 
the present invention can be utilized in xerographic imaging apparatuses 
wherein image toning and transfer are accomplished electrostatically, and 
transferred images are fixed in a separate step by means of a pressure 
roll with or without the assistance of thermal or photochemical energy 
fusing. 
In copending U.S. patent applications U.S. Pat. No. 5,135,832 (D/90192), 
U.S. Ser. No. 609,316 (D/90192Q) and U.S. Ser. No. 636,136 (now abandoned) 
(D/90152), the disclosures of which are totally incorporated herein by 
reference, there are illustrated colored magnetic toners comprised of 
magnetic particles of high tinctorial strength based on iron, chromium, or 
nickel dispersed in a core resin and containing whitening agents, such as 
titanium oxide, as well as a colored pigment, and which core is 
encapsulated by a polyurea shell containing conductive colorless additives 
on the surface. 
In U.S. Pat. No. 4,443,527, the disclosure of which is incorporated herein 
by reference, there are disclosed magnetic particles such as chromium, 
nickel, iron, or cobalt oxides to produce yellow, brown or reddish color 
toner composition containing a mixture of finely divided reflecting 
pigment such as titanium dioxide coated on the metal particle as an 
external additive and contacting the masked particle with a suitable dye 
or pigment composition, wherein the dye or pigment coats or becomes 
embedded in said masking layer and dispersed in a fusible binder resin. 
Note that the masking coated layer and colored pigment is not bound to the 
seed magnetic particle and wherein the magnetic dye composite is 
conductive. In U.S. Pat. No. 4,623,602, substantially the same approach is 
disclosed except that the masking layer and colored layer contain a yellow 
fluoresecent dye, and binders are used in which the dye fluoresces. In 
U.S. Pat. No. 5,021,315, the disclosure of which is totally incorporated 
herein by reference, there is illustrated a process for overcoating a 
finely dispersed metal oxide by an in situ process where the metal oxide 
is in the size range of 1 to about 50 microns. Magnetic oxide particles 
are coated by depositing a layer of finely divided submicron sized 
particles of copper oxide onto the surface of the core magnetic metal 
oxide particles, followed by a subsequent reduction of the deposited 
copper oxide on the surface of the magnetic particle to metallic copper, 
and wherein such composite displays a resistivity of from about 10.sup.5 
to 10.sup.7 ohm-cm, or conductivity of from about 10.sup.-5 to 10.sup.-7 
(ohm-cm).sup.-1. The processes of this patent enable, for example, red 
colored conductive magnetic particles suitable for colored toner 
compositions. However, only iron oxide is used as the seed magnetic 
particle and is of high tinctorial strength, and wherein the process 
involves the reduction of copper oxide to copper, and furthermore, 
conductivity of less than 10.sup.-5 (ohm-cm).sup.-1 cannot be obtained. 
The processes of the present invention in embodiments provides advantages 
over the prior art indicated in that, for example, there is provided a 
simple and direct electrochemical oxidation-reduction method to produce a 
metallic magnetic core particle coated with a conductive lightly colored 
metal layer, and that a subsequent in situ oxidation with a halide 
provides an overcoating of highly conductive particle of from about 0.1 to 
10.sup.-4 (ohm-cm).sup.-1 and needed for use in specific inductive 
ionographic processes. Additionally, a lightness value of from about 0 to 
about 40 units needed in embodiments to obtain high color intensity prints 
can be achieved with the toners of the present invention. 
The following United States patents are mentioned in a patentability search 
report for patent application U.S. Ser. No. 609,333 U.S. Pat. No. 
5,135,832 (D/90192), the disclosure of which is totally incorporated 
herein by reference, relating to encapsulated toners, and entitled Colored 
Toner Compositions: 4,803,144, which discloses an encapsulated toner with 
a core containing as a magnetizable substance a magnetite, see Example 1, 
which is black in color, wherein on the outer surface of the shell there 
is provided a white electroconductive powder, preferably a metal oxide 
powder, such as zinc oxide, titanium oxide, tin oxide, silicon oxide, 
barium oxide and others, see column 3, line 59, to column 4; in column 8 
it is indicated that the colorant can be carbon black, blue, yellow, and 
red; in column 14 it is indicated that the electroconductive toner was 
employed in a one component developing process with magnetic brush 
development, thus it is believed that the toner of this patent is 
substantially insulating; 4,937,167 which relates to controlling the 
electrical characteristics of encapsulated toners, see for example columns 
7 and 8, wherein there is mentioned that the outer surface of the shell 
may contain optional surface additives 7, examples of which include fumed 
silicas, or fumed metal oxides onto the surfaces of which have been 
deposited charge additives, see column 17 for example; 4,734,350 which 
discloses an improved positively charged toner with modified charge 
additives comprised of flow aid compositions having chemically bonded 
thereto, or chemically adsorbed on the surface certain amino alcohol 
derivatives, see the Abstract for example; the disclosures of each of the 
aforementioned patents being totally incorporated herein by reference; and 
which according to the search report are not significant but may be of 
some background interest 2,986,521; 4,051,077; 4,108,653; 4,301,228; 
4,301,228; 4,626,487; 3,590,000; 3,983,045; 4,035,310; 4,298,672; 
4,338,390; 4,560,635; 4,952,477; 4,939,061; 4,937,157; 4,904,762 and 
4,883,736, the disclosures of each of these patents being totally 
incorporated herein by reference. 
There is a need for lightly colored conductive magnetic particles, and in 
particular lightly colored conductive magnetic particles for the 
preparation of colored magnetic toner compositions with many of the 
advantages illustrated herein. There is a need for conductive magnetic 
particles with high magnetic saturation strengths of from about 30 emu per 
gram to about 120 emu per gram and more preferably from about 60 emu per 
gram to about 100 emu per gram. Additionally, there is a need for 
conductive magnetic particles which display conductivity of from about 
10.sup.-4 (ohm-cm).sup.-1 to about 10.sup.-8 (ohm-cm).sup.-1, particularly 
in xerographic process, and from about 0.1 (ohm-cm).sup.-1 to about 
10.sup.-4 (ohm-cm).sup.-1, particularly in ionographic process. 
Furthermore, there is a need for lightly colored magnetic conductive 
particles with lightness value of from about 0 to about 60 units and 
preferably from about 0 to about 40 units measured by the Match-Scan II 
spectrometer available from Vidan Corporation. Moreover, there is a need 
for lightly colored magnetic particles which display low tinctorial 
strength of chroma such as from about 0 to about 40 units and hue from 
about 0 to about 40 units, and preferably may be colorless, such that the 
chroma, lightness and hue values are about 0 units. Moreover, there is a 
need for brightly colored magnetic toner compositions displaying bright 
red, orange, cyan, magenta and yellow color which contain resin pigments 
and the aforementioned lightly colored and low tinctorial strength 
conductive magnetic particles. Additionally, there is a need for lightly 
colored magnetic conductive particles with a diameter size of from about 
0.5 micron to about 25 microns and more preferably from about 0.1 micron 
to about 6 microns as measured by the Coulter Counter. Another associated 
need resides in the provision of preparative processes for obtaining 
lightly colored conductive magnetic particles, which possess a particle 
size diameter of 0.5 micron to about 25 microns, a magnetic saturation 
strength of from about 30 emu per gram to about 120, and a conductivity of 
from about 10.sup.-4 (ohm-cm).sup.-1 to about 10.sup.-8 (ohm-cm).sup.-1. 
SUMMARY OF THE INVENTION 
It is a feature of the present invention to provide a process for the 
preparation of lightly colored conductive magnetic particles with many of 
the advantages illustrated herein. 
In another feature of the present invention there are provided processes 
for formation of magnetic particles bounded with a lightly colored 
metallic coating layer of low tinctorial strength. 
In another feature of the present invention there are provided processes 
for the formation of magnetic particles bounded with a lightly colored 
metallic coating layer bounded thereover with an overcoated metal halide 
or oxide layer of low tinctorial strength. 
In another feature of the present invention there are provided processes 
for formation of conductive magnetic particles bounded with a lightly 
colored metallic coating layer. 
In another feature of the present invention there are provided processes 
for formation of magnetic particles bounded with a lightly colored 
metallic coating layer containing thereover an overcoated metal halide or 
oxide layer of high conductivity. 
It is still another feature of the present invention to provide lightly 
colored conductive magnetic particles suitable for incorporation in 
colored toner compositions. 
It is still another feature of the present invention to provide lightly 
colored conductive magnetic particles with magnetic properties suitable 
for incorporation in color toner compositions utilized in single component 
magnetic development in electrophotographic devices. 
It is still another feature of the present invention to provide lightly 
colored conductive magnetic particles with high conductivity properties 
suitable for incorporation in colored developers utilized in single 
component inductive development in ionographic devices. 
Also, an additional feature of the present invention resides in the 
provision of lightly colored conductive magnetic particles, colorants such 
as colored pigments or dyes with a wide spectrum of colors such as red, 
blue, green, brown, yellow, magenta, cyan, and mixtures thereof, for 
incorporation in toner compositions wherein the light coloration of the 
magnetic particles does not interfere substantially with the color of the 
dye or pigment. 
In another feature of the present invention there are provided toner and 
developer compositions. 
These and other features of the present invention can be accomplished by 
the provision of magnetic core particles coated with a lightly colored 
metallic coating layer, and more specifically by the provision of 
processes involving an electrodeless electrochemical oxidation-reduction 
reaction of the surface of the core magnetic particles. In one embodiment 
of the present invention, there are provided processes in which a metallic 
magnetic particle is dispersed in a solution of a soluble salt of a metal 
cation in a suitable solvent, such that the metallic magnetic core 
particle undergoes a spontaneous electrochemical oxidation reaction at the 
particle surface, wherein the metal is oxidized to the corresponding metal 
cation, while the soluble metal cation in solution undergoes a spontaneous 
electrochemical reduction reaction at the particle surface to form a 
metallic surface corresponding to the reduction of the soluble metal 
cation. 
In embodiments of the present invention, there are provided toner 
compositions comprised of resin particles and a colored highly conductive 
magnetic composition comprised of a core comprised of a metal, thereover a 
coating comprised of a lightly colored metal such as copper, tin, 
aluminum, manganese, cobalt or silver and a top coating comprised of a 
substantially colorless metal halide such as copper iodide or oxide such 
as tin oxide, aluminum oxide or titanium oxide. 
One embodiment of the present invention is directed to a toner composition 
comprised of resin particles and a colored highly conductive magnetic 
composition comprised of a core comprised of a metal, and thereover a 
coating comprised of a lightly colored metal selected from the group 
consisting of copper, silver, cobalt, tin, gold, manganese, titanium, 
magnesium, vanadium, chromium, zinc, cadmium, indium, rhodium, niobium, 
platinum and aluminum, and in contact with the lightly colored metal a top 
coating comprised of a substantially colorless metal halide selected from 
the group consisting of copper iodide, copper bromide, copper chloride, 
magnesium iodide, cobalt iodide, silver iodide, vanadium chloride, 
chromium chloride, and platinum chloride. 
In an embodiment of the present invention, there is provided a toner 
component comprised of coating of magnetic core particles with a lightly 
colored metallic layer, which core is prepared by a process involving an 
electrodeless electrochemical oxidation-reduction reaction of the surface 
of the core magnetic particles, and thereover, overcoated with a colorless 
or lightly colored metal halide. In one embodiment of the present 
invention, there are provided processes in which a metallic magnetic 
particle is dispersed in a solution of a soluble salt of a metal cation in 
a suitable solvent, such that the metallic magnetic core particle 
undergoes a spontaneous electrochemical oxidation reaction at the particle 
surface, wherein the metal is oxidized to the corresponding metal cation, 
while the soluble metal cation in solution undergoes a spontaneous 
electrochemical reduction reaction at the particle surface to form a 
metallic surface corresponding to the reduction of the soluble metal 
cation; subsequently followed by oxidizing partially or all of the lightly 
colored metal coating with a halide or peroxide yielding a metal halide or 
oxide overcoating. 
In embodiments of the present invention, there are provided processes where 
the magnetic core particle has a particle size diameter of from about 0.5 
micron to about 25 microns, and preferably from about 1 micron to about 6 
microns as measured by the Coulter Counter, and wherein the magnetic core 
particle is selected from the group consisting of metals where the 
saturation magnetic moment of the magnetic particles is between about 30 
to about 120 emu per gram, and preferably between about 60 to about 100 
emu per gram, and wherein the conductivity of the lightly colored 
conductive magnetic particles are from about 0.1 (ohm-cm).sup.-1 to about 
10.sup.-8 (ohm-cm).sup.-1, the lightness of the colored metal coating and 
metal halide or oxide overcoating is from about 0 to about 60 units, and 
the tinctorial strengths of the magnetic particles are of chroma and hue 
of from about 0 to about 40 units. 
In an embodiment, the lightly colored conductive magnetic particle 
comprised of a core comprised of an iron metal and coated thereover with a 
copper metal can be prepared by (i) suspending about 1.0 mole percent to 
about 1.2 mole percent by weight of iron powder (commercially available as 
SICOPUR 4068FF.TM., average particle diameter of 4 microns) in about 0.5 
to about one liter of water; (ii) adding a catalytic amount of sulfuric 
acid of from about 0.0001 mole percent to about 0.01 mole percent; (iii) 
followed by a slow addition of the soluble metal cation salt of from about 
0.05 mole percent to about 0.3 mole percent by weight such as 
copper(II)sulfate over a period of 1 minutes to about 10 minutes, thus 
effecting a spontaneous oxidation-reduction reaction at a temperature of 
from about 10.degree. C. to about 30.degree. C., and optionally cooling 
this exotherm reaction such that the bath temperature is maintained from 
about 10.degree. C. to about 60.degree. C.; (iv) followed by filtration of 
the lightly colored magnetic particle, washing with water and isolation by 
air dry filtration, spray drying or fluid bed dring process. 
In another embodiment, the lightly colored conductive magnetic particle 
comprised of a core comprised of an iron metal and coated thereover with a 
copper metal, and overcoated thereover with a copper iodide layer can be 
prepared by (i) suspending about 1.0 mole percent to about 1.2 mole 
percent by weight of iron powder (commercially available as SICOPUR 
4068FF.TM., average particle diameter of 4 microns) in about 0.5 to about 
one liter of water; (ii) adding a catalytic amount of sulfuric acid of 
from about 0.0001 mole percent to about 0.01 mole percent; (iii) followed 
by a slow addition of from about one minute to about 20 minutes of the 
soluble metal cation salt of from about 0.05 mole percent to about 0.3 
mole percent by weight such as copper(II)sulfate over a period of about 1 
minute to about 10 minutes, thus effecting a spontaneous 
oxidation-reduction reaction at a temperature of from about 10.degree. C. 
to about 30.degree. C., and optionally cooling this exotherm reaction with 
ice-water bath such that the bath temperature is maintained from about 
10.degree. C. to about 60.degree. C.; (iv) followed by filtration by 
vacuum suction of the lightly colored magnetic particle, washing with 
water and resuspending the particles in about 0.5 liter to about one liter 
of water; (v) followed by the addition of from about 0.025 mole percent to 
about 0.2 mole percent of iodine, thus effecting the oxidation of the 
copper coating to copper iodide at a temperature of from about 10.degree. 
C. to about 30.degree. C.; (vi) followed by filtration of the lightly 
colored magnetic particle, washing with an aqueous solution of from about 
0.1 to about 5 percent by weight of water and sodium thiosulfate and 
followed by washing with water, and isolation by air dry filtration, spray 
drying or fluid bed drying process. 
Illustrative examples of magnetic core particles that can be selected for 
the present invention include iron powder, such as those derived from the 
reduction of iron tetracarbonyl, and commercially available from BASF as 
SICOPUR 4068 FF.TM.; cobalt powder, commercially available from Noah 
Chemical Company; METGLAS.TM. and ultrafine METGLAS.TM., commercially 
available from Allied Company; treated iron oxides such as BAYFERROX 
AC5106M.TM., commercially available from Mobay; treated iron oxide 
TMB-50.TM., commercially available from Magnox; CARBONYLIRON SF.TM., 
commercially available from GAF Company; MAPICO TAN.TM., commercially 
available from Columbia Company; treated iron oxide MO-2230.TM., 
commercially available from Pfizer Company; nickel powder ONF 2460.TM., 
commercially available from Sherritt Gordon Canada Company; nickel powder; 
chromium powder; manganese ferrites; and the like. The preferred average 
diameter particle size of the magnetic material is from about 0.05 micron 
to about 25 microns, although other particle sizes may also be utilized. 
In embodiments of the present invention, there are provided processes where 
the electrochemical reduction potential of the soluble coating metal 
cation salt in the solution is more positive by about 10.sup.-2 volts to 
about 10 volts or more than the electrochemical reduction potential of the 
core magnetic metallic particle to be coated, such that the overall 
electrochemical potential of the reduction of the soluble metal ion in 
solution combined with the oxidation of the metal surface of the core 
magnetic particle results in a spontaneous reaction. Illustrative examples 
of soluble metal salts in solvents, such as water or alcohol of from about 
0.05 moles per liter to about 10 moles per liter, that can be selected 
include soluble metal salts containing the metal ions Sn.sup.+2, 
Pb.sup.+2, Sn.sup.+4, Cu.sup.+, Cu.sup.+2, Ag.sup.+, Pt.sup.+2, Au.sup.+, 
or the metal ion containing species Cu.sub.2 Cl.sub.3 or Hg.sub.2 
Cl.sub.2. Preferred metal ions are those that are lightly colored in the 
metallic state, such as tin which is white in color, copper which is light 
red in color, silver which is white or silver in color, platinum which is 
white in color, or gold which is light yellow in color. Illustrative 
examples of suitable counterions or the soluble metal species include 
fluoride, chloride, bromide, iodide, sulfate, nitrate, acetate, 
thiocyanate, or cyanide, mixtures thereof, and the like. 
Illustrative examples of suitable solvents that may be employed at a ratio 
of from about 1 to about 1,000 parts compared to the metal and metal ions, 
include water. Other suitable solvents that may be employed include 
aliphatic with, for example 1 to about 25 carbon atoms, alcohols such as 
methyl alcohol, ethyl alcohol, butyl alcohol, propyl alcohol, isopropyl 
alcohol, isobutyl alcohol, tertiary, decyl alcohol, amyl alcohol, and 
isoamyl alcohol. Other suitable solvents include, but are not limited to, 
acetone, dimethylformamide, tetrahydrofuran, ethyl acetate, 
dichloromethane, and chloroform. 
Optional catalysts selected in effective amounts of, for example, from 
about 0.01 percent by weight to about 0.1 percent by weight of metal that 
may be employed include acids, such as for example hydrochloric acid, 
hydrofluoric acid, hydrobromic acid, hydroiodic acid, acetic acid, nitric 
acid, sulfuric acid, phosphoric acid, and boric acid. Other catalysts that 
may be employed include bases such as sodium hydroxide, potassium 
hydroxide, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, 
sodium carbonate, and potassium carbonate. Additional catalysts that may 
be employed include soluble salts, including, but not limited to, salts 
containing fluoride, chloride, bromide, iodide, sulfate, nitrate, sulfate, 
acetate, tiocyanate, or cyanide counterions. 
Illustrative examples of suitable halides or peroxides selected in 
effective amounts of, for example, from about 0.1 to about 30 percent by 
weight of metal to partially or fully oxidize the lightly colored metal 
coating to the metal halide or oxide overcoating that can be selected 
include iodine, chlorine, bromine, fluorine, hydrogen peroxide, 
di-t-butylperoxide, other organo-oxides known in the art, mixtures thereof 
and the like. 
An illustrative specific example of lightly colored conductive magnetic 
material is comprised of 1 mole of metal, such as iron powder, coated with 
from about 0.1 mole to about 0.3 mole percent of metal coating such as 
copper, and thereover a coating with from about 0.1 to about 0.2 mole 
percent of a metal halide such as copper iodide. 
Illustrative examples of suitable toner resins selected for the toner and 
developer compositions of the present invention, and present in various 
effective amounts such as, for example, from about 20 percent by weight to 
about 95 percent by weight, include polyesters, polyamides, polywaxes, 
ELVAX.TM., VERSAMID.TM., epoxy resins, polyurethanes, polyolefins, 
polyethylene oxide, vinyl resins and polymeric esterification products of 
a dicarboxylic acid and a diol comprising a diphenol, and mixtures 
thereof. Various suitable vinyl resins may be selected as the toner resin 
including homopolymers or copolymers of two or more vinyl monomers. 
Typical vinyl monomeric units include styrene, p-chlorostyrene, vinyl 
naphthalene, unsaturated mono-olefins such as ethylene, propylene, 
butylene, isobutylene and the like; vinyl halides such as vinyl chloride, 
vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl 
benzoate, and vinyl butyrate; vinyl esters such as esters of 
monocarboxylic acids including methyl acrylate, ethyl acrylate, n-butyl 
acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, 
2-chloroethyl acrylate, phenyl acrylate, methylalpha-chloroacrylate, 
methyl methacrylate, ethyl methacrylate, and butyl methacrylate; 
acrylonitrile, methacrylonitrile, acrylamide; vinyl ethers such as vinyl 
methyl ether, vinyl isobutyl ether, and vinyl ethyl ether; N-vinyl indole; 
N-vinyl pyrrolidone; and the like. Examples of specific toner resins 
include styrene butadiene copolymers, especially styrene butadiene 
copolymers prepared by a suspension polymerization process, reference U.S. 
Pat. No. 4,558,108, the disclosure of which is totally incorporated herein 
by reference; and mixtures thereof. 
As one toner resin there can be selected the esterification products of a 
dicarboxylic acid and a diol comprising a diphenol, which components are 
illustrated in U.S. Pat. No. 3,590,000, the disclosure of which is totally 
incorporated herein by reference. Other preferred toner resins included 
styrene/methacrylate copolymers, styrene/acrylate copolymers, and 
styrene/butadiene copolymers, especially those as illustrated in the 
aforementioned patent; and styrene butadiene resins with high styrene 
content, that is exceeding from about 80 to 85 percent by weight of 
styrene, which resins are available as PLIOLITES.RTM. from Goodyear 
Chemical Company; 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, 1,3-butanediol, 1,2-propanediol and 
pentaerythritol; polyesters such as those derived from isophthalic acid, 
fumaric acid and glycols such as SR II.RTM. resins available from 
Ashley Chemicals Company; other resins comprise mixtures of polyethylene 
oxides such as ELVAX.RTM. available from DuPont Corporation or 
POLYWAX.RTM. available from Petrolite Chemicals Company, and polyamides 
such as VERSAMID.RTM. available from Henkle Chemicals Company. 
Illustrative examples of pigments that may be present in the toner 
composition in effective amounts, such as for example from about 1 to 
about 12 percent by weight, of toner include HELIOGEN BLUE.TM., HOSTAPERM 
PINK.TM., NOVAPERM YELLOW.TM., LITHOL SCARLET.TM., MICROLITH BROWN.TM., 
SUDAN BLUE.TM., FANAL PINK.TM., PV FAST BLUE.TM., mixtures thereof, known 
cyans, yellows and magentas, and the like. 
Illustrative examples of optional charge enhancing additives present in the 
toner in various effective amounts, such as for example from about 0.1 to 
about 20 percent by weight, include alkyl pyridinium halides, such as 
cetyl pyridinium chlorides, reference U.S. Pat. No. 4,298,672, the 
disclosure of which is totally incorporated herein by reference, cetyl 
pyridinium tetrafluoroborates, quaternary ammonium sulfate, and sulfonate 
charge control agents as illustrated in U.S. Pat. No. 4,338,390, the 
disclosure of which is totally incorporated herein by reference; stearyl 
phenethyl dimethyl ammonium tosylates, reference U.S. Pat. No. 4,338,390, 
the disclosure of which is totally incorporated herein by reference; 
distearyl dimethyl ammonium methyl sulfate, reference U.S. Pat. No. 
4,560,635, the disclosure of which is totally incorporated herein by 
reference; stearyl dimethyl hydrogen ammonium tosylate; and other known 
similar charge enhancing additives providing the objectives of the present 
invention are accomplished; and the like.

The following Examples are being submitted to further define various 
species of the present invention. These examples are intended to be 
illustrative only and are not intended to limit the scope of the present 
invention. 
EXAMPLE I 
Synthesis of a reddish conductive magnetic particle comprised of 80 percent 
by weight of iron and coated with 20 percent by weight of copper metal. 
Iron powder (SICOPUR 4068FF.TM., 500 grams, obtained from BASF) was 
suspended in water (4 liters) containing a catalytic amount of 
concentrated sulfuric acid (5 milliliters). To this suspension was then 
added slowly, over a five minute period, copper(II)sulfate (200 grams). 
The resulting solution was stirred for 1 hour, wherein the iron powder 
surface was oxidized to iron sulfate (soluble in water) and the 
copper(II)sulfate was reduced onto the seed iron powder metal to copper. 
The resultant reddish product was then filtered off by vacuum filtration, 
and washed with water and then air dried to yield the above reddish 
magnetic material (480 grams) comprised of iron core of about 80 percent 
by weight, and a lightly colored copper metal coating of about 20 percent 
by weight. The resulting red magnetic particles had a volume average 
particle diameter of 3.8 microns and a particle size distribution of 1.38 
as determined by Coulter Counter measurements using Coulter Counter Model 
ZM, available from Coulter Electronics, Inc. 
The saturation magnetic moment of the above product was then obtained by 
referencing its induced current per gram by using 10 grams of sample 
(above prepared reddish color particle product) to that of a 10 gram 
sample of nickel. For the magnetic particles of this Example, the 
saturation magnetic moment was 80 emu per gram. The conductivity was 
obtained by preparing a pressed pellet of the product at 2,000 pounds per 
square inch, and employing a standard conductivity meter device. For the 
magnetic particles of this Example, the conductivity was measured to be 
4.times.10.sup.-5 (ohm-cm).sup.-1. The red color of this magnetic material 
was stable even after 12 months of storage at room temperature, about 
25.degree. C. The color properties of the above prepared product were then 
measured using the Match-Scan II spectrometer available from Vidan 
Corporation, and for the prepared magnetic particles the lightness value 
was 32 units, the chroma was 10 units and the hue was 20 units. 
EXAMPLE II 
Synthesis of a reddish conductive magnetic particle comprised of 90 percent 
by weight of iron and coated with 10 percent by weight of copper metal: 
Iron powder (SICOPUR 4068FF.TM., 500 grams, obtained from BASF) is 
suspended in water (4 liters) containing a catalytic amount of sulfuric 
acid (5 milliliters). To this suspension is then added slowly 
copper(II)sulfate (100 grams) over a five minute period. The solution 
resulting was stirred for 1 hour, wherein the iron powder surface was 
oxidized to iron sulfate (soluble in water) and the copper(II)sulfate was 
reduced onto the seed iron powder metal to copper. The resultant reddish 
product was then filtered off by vacuum filtration and washed with water, 
and then air dried to yield the reddish magnetic material (490 grams) 
comprised of iron core of about 90 percent by weight, and a lightly 
colored copper coating of about 10 percent by weight. The resulting red 
magnetic particles had a volume average particle diameter of 3.6 microns 
and a particle size distribution of 1.38 as determined by Coulter Counter 
measurements using Coulter Counter Model ZM, available from Coulter 
Electronics, Inc. 
The saturation magnetic moment was then obtained by referencing its induced 
current per gram by using 10 grams of sample product to that of a 10 gram 
sample of nickel. For the magnetic particles of this Example, the 
saturation magnetic moment was 90 emu per gram. The conductivity was 
obtained by preparing a pressed pellet of the product at 2,000 pounds per 
square inch using a press, and employing a standard conductivity meter 
device. For the magnetic particles of this Example, the conductivity was 
measured to be 1.times.10.sup.-6 (ohm-cm).sup.-1. The color properties 
were then measured using the Match-Scan II spectrometer available from 
Vidan Corporation, and for the magnetic particles of this Example the 
lightness value was 38 units, the chroma was 19 units and the hue was 28 
units. The lightness, chroma and hue properties of this magnetic material 
did not change even after 12 months of storage at room temperature, about 
25.degree. C. 
EXAMPLE III 
Synthesis of a reddish conductive magnetic particle comprised of 80 percent 
by weight of cobalt and coated with 20 percent by weight of copper metal: 
Cobalt powder (Noah Chemical Corporation, 500 grams) is suspended in water 
(4 liters) containing a catalytic amount of icalulfuric acid (5 
milliliters). To this suspension was then added slowly copper(II)sulfate 
(200 grams) over a five minute period. The solution resulting was stirred 
for 1 hour, wherein the iron powder surface was oxidized to iron sulfate 
(soluble in water), and the copper(II)sulfate was reduced onto the seed 
iron powder metal to copper. The resultant reddish-brown product was then 
filtered by vacuum filtration and washed with water, and then air dried to 
yield the reddish magnetic material product (485 grams) comprised of 
cobalt core of about 80 percent by weight, and a lightly colored copper 
coating of about 20 percent by weight. The resulting reddish-brown 
magnetic particles had a volume average particle diameter of 1.8 microns 
and a particle size distribution of 1.26 as determined by Coulter Counter 
measurements using Coulter Counter Model ZM, available from Coulter 
Electronics, Inc. 
The saturation magnetic moment was then obtained by referencing its induced 
current per gram by using 10 grams of sample to that of a 10 gram sample 
of nickel. For the magnetic particles of this Example, the saturation 
magnetic moment was 80 emu per gram. The conductivity was obtained by 
preparing a pressed pellet at 2,000 pounds per square inch, and employing 
a standard conductivity meter device. For the magnetic particles of this 
Example, the conductivity was measured to be 3.times.10.sup.-5 
(ohm-cm).sup.-1. The red color of this magnetic material stable was even 
after 12 months of storage at room temperature. The product color 
properties were then measured using the Match-Scan II spectrometer 
available from Vidan Corporation, and for the magnetic particles of this 
Example the lightness value was 28 units, the chroma was 9 units and the 
hue was 21 units. 
EXAMPLE IV 
Synthesis of a reddish conductive magnetic particle comprised of 80 percent 
by weight of iron and coated with 10 percent by weight of copper metal and 
overcoated with 10 percent by weight of copper iodide: 
Iron powder (SICOPUR 4068FF.TM., 500 grams) was suspended in water (4 
liters) containing a catalytic amount of sulfuric acid (5 milliliters). To 
this suspension was then added slowly copper(II)sulfate (200 grams) over a 
five minute period. The solution resulting was stirred for 1 hour, wherein 
the iron powder surface was oxidized to iron sulfate (soluble in water) 
and the copper(II)sulfate was reduced onto the seed iron powder metal to 
copper. The resultant reddish product was then filtered off, washed with 
water and resuspended in 1 liter of water and 1 liter of methanol. To this 
suspension was then added 50 grams of iodine and stirring continued for a 
period of two hours, after which an aqueous solution of 5 percent by 
weight of sodium thiosulfate was added until the excess iodine was 
destroyed, followed by filtration, washing with water, and then air dried 
to yield a lightly red colored magnetic material (490 grams) comprised of 
iron core of about 80 percent by weight, a lightly colored copper coating 
of about 10 percent by weight, and a colorless overcoating comprised of 
copper iodide of about 10 percent by weight. The resulting reddish 
magnetic particles had a volume average particle diameter of 3.8 microns 
and a particle size distribution of 1.36 as determined by Coulter Counter 
measurements using Coulter Counter Model ZM, available from Coulter 
Electronics, Inc. 
The saturation magnetic moment was then obtained by referencing its induced 
current per gram by using 10 grams of sample product to that of a 10 gram 
sample of nickel. For the magnetic particles of this Example, the 
saturation magnetic moment was 82 emu per gram. The conductivity was 
obtained by preparing a pressed pellet of the product at 2,000 pounds per 
square inch, and employing a standard conductivity meter device. For the 
magnetic particles of this Example, the conductivity was measured to be 
2.times.10.sup.-2 (ohm-cm).sup.-1. The red color of this magnetic material 
was stable even after 12 months of storage at room temperature. The color 
properties were then measured using the Match-Scan II spectrometer 
available from Vidan Corporation, and for the magnetic particles of this 
Example the lightness value was 12 units, the chroma was 2 units and the 
hue was 8 units. 
EXAMPLE V 
Synthesis of a reddish conductive magnetic particle comprised of 80 percent 
by weight of iron and coated with 5 percent by weight of copper metal and 
overcoated with 15 percent by weight of copper iodide: 
Iron powder (SICOPUR 4068FF.TM., 500 grams) is suspended in water (4 
liters) containing a catalytic amount of sulfuric acid (5 milliliters). To 
this suspension is then added slowly copper(II)sulfate (200 grams) over a 
five minute period. The solution is stirred for 1 hour, wherein the iron 
powder surface is oxidized to iron sulfate (soluble in water) and the 
copper(II)sulfate is reduced onto the seed iron powder metal to copper. 
The resultant reddish product is then filtered off, washed with water and 
resuspended in 1 liter of water and 1 liter of methanol. To this 
suspension is then added 75 grams of iodine and strirring continued for a 
period of two hours, after which an aqueous solution of 5 percent by 
weight of sodium thiosulfate is added until the excess iodine is 
destroyed, followed by filtration, washed with water and then air dried to 
yield a lightly red colored magnetic material (490 grams) comprised of 
iron core of about 80 percent by weight, a lightly colored copper coating 
of about 5 percent by weight, and a colorless overcoating comprised of 
copper iodide of about 15 percent by weight. The resulting reddish 
magnetic particles had a volume average particle diameter of 3.6 microns 
and a particle size distribution of 1.32 as determined by Coulter Counter 
measurements using Coulter Counter Model ZM, available from Coulter 
Electronics, Inc. 
The saturation magnetic moment was then obtained by referencing its induced 
current per gram by using 10 grams of sample product to that of a 10 gram 
sample of nickel. For the magnetic particles of this Example, the 
saturation magnetic moment was 91 emu per gram. The conductivity was 
obtained by preparing a pressed pellet, 25 grams of product, at 2,000 
pounds per square inch, and employing a standard conductivity meter 
device. For the magnetic particles of this Example, the conductivity was 
measured to be 3.times.10.sup.-3 (ohm-cm).sup.-1. The red color of this 
magnetic material was stable even after 12 months of storage at room 
temperature. The color properties were then measured using the Match-Scan 
II spectrometer available from Vidan Corporation, and for the magnetic 
particles of this Example the lightness value was 18 units, the chroma was 
12 units and the hue was 21 units. 
EXAMPLE VI 
Synthesis of a reddish conductive magnetic particle comprised of 80 percent 
by weight of cobalt and coated with 10 percent by weight of copper metal 
and overcoated with 10 percent by weight of copper iodide: 
Cobalt powder (500 grams) is suspended in water (4 liters) containing a 
catalytic amount of sulfuric acid (5 milliliters). To this suspension is 
then added slowly copper(II)sulfate (100 grams) over a five minute period. 
The solution is stirred for 1 hour, wherein the iron powder surface is 
oxidized to iron sulfate (soluble in water) and the copper(II)sulfate is 
reduced onto the seed iron powder metal to copper The resultant reddish 
product is then filtered off, washed with water and resuspended in 1 liter 
of water and 1 liter of methanol. To this suspension is then added 50 
grams of iodine and stirring continued for a period of two hours, after 
which an aqueous solution of 5 percent by weight of sodium thiosulfate is 
added until the excess iodine is destroyed, followed by filtration, washed 
with water and then air dried to yield the above lightly red colored 
magnetic material (490 grams) comprised of cobalt core of about 80 percent 
by weight, a lightly colored copper coating of about 10 percent by weight, 
and a colorless overcoating comprised of copper iodide of about 10 percent 
by weight. The resulting reddish-brown magnetic particles had a volume 
average particle diameter of 1.9 microns and a particle size distribution 
of 1.28 as determined by Coulter Counter measurements using Coulter 
Counter Model ZM, available from Coulter Electronics, Inc. 
The saturation magnetic moment was then obtained by referencing its induced 
current per gram; 10 grams of sample product to that of a 10 gram sample 
of nickel. For the magnetic particles of this Example, the saturation 
magnetic moment was 82 emu per gram. The conductivity was obtained by 
preparing a pressed pellet, 50 grams of proudct sample, at 2,000 pounds 
per square inch, and employing a standard conductivity meter device. For 
the magnetic particles of this Example, the conductivity was measured to 
be 2.times.10.sup.-3 (ohm-cm).sup.-1. The red color of this magnetic 
material was stable even after 12 months of storage at room temperature. 
The color properties were then measured using the Match-Scan II 
spectrometer available from Vidan Corporation, and for the magnetic 
particles of this Example the lightness value was 19 units, the chroma was 
7 units and the hue was 18 units. 
EXAMPLE VII 
Synthesis of a conductive colored toner composition containing the magnetic 
particles of Example I 
A mixture of 108.0 grams of POLYWAX 2,000.TM. (polyethylene oxide available 
from Petrolite Corporation), 24.0 grams of ELVAX 420.TM. (polyalkylene 
oxide available from E. I. DuPont), 24.0 grams of VERSAMID 744.TM. (a 
polyamide available from Henkle Inc.), 168.0 grams of iron-copper powder 
(Example I), and 28.0 grams of LITHOL SCARLET.TM. pigment was mixed and 
ground in a Fitzmill Model J equipped with a 850 micrometer screen. After 
grinding, the mixture was dry blended first on a paint shaker and then on 
a roll mill. A small counter-rotating twin screw extruder (DAVO.TM.) was 
then used to melt mix the aforementioned mixture. A K-Tron twin screw 
volumetric feeder was employed in feeding the mixture to the extruder 
which had a barrel temperature of 150.degree. C. (flat temperature 
profile), and a screw rotational speed of 60 rpm with a feed rate of 10 
grams per minute. The extruded strands were broken down into coarse 
particles by passing them through a Model J Fitzmill twice, first with an 
850 micrometer screen, and then with a 425 micrometer screen. The coarse 
particles thus produced were micronized using an 8 inch Sturtevant 
micronizer and classified in a Donaldson classifier. The resulting red 
toner had a volume average particle diameter of 19.1 microns and a 
particle size distribution of 1.31 as determined by Coulter Counter 
measurements using Coulter Counter Model ZM, available from Coulter 
Electronics, Inc. 
The toner's saturation magnetic moment was then obtained by referencing its 
induced current per gram, 3 grams to that of a 10 gram sample of nickel. 
For the toner of this Example, the saturation magnetic moment was 46.0 emu 
per gram. The toner's conductivity was measured by preparing a pressed 
pellet of the toner at 2,000 pounds per square inch and using a 
conductivity meter unit. The conductivity of the toner of this example was 
8.8.times.10.sup.-6 (ohm-cm).sup.-1. 
The above prepared toner was evaluated in a Xerox Corporation 4060.TM. 
printer. The toned images were transfixed onto paper with a transfix 
pressure of 4,000 psi. Print quality was evaluated from a checkerboard 
print pattern. The image optical density was measured with a standard 
integrating densitometer. Image fix was measured by the standardized 
scotch tape pull method, and was expressed as a percentage of the retained 
image optical density after the tape test relative to the original image 
optical density. Image smearing was evaluated qualitatively by hand 
rubbing the fused checkerboard print using a blank paper under an applied 
hand force, and viewing the surface cleanliness of unprinted and printed 
areas of the page. Image ghosting on paper was evaluated visually. For the 
above prepared toner, the image fix level was 71 percent, and no image 
smear and no image ghosting were observed in this machine testing for 
2,000 prints. The color properties of a print were then measured using the 
Match-Scan II spectrometer, and for the toner image of this example, the 
lightness was 55 units, the chroma was 71 units and the hue was 68 units. 
EXAMPLE VIII 
Synthesis of a conductive colored toner composition containing the magnetic 
particles of Example IV 
A mixture of 108.0 grams of POLYWAX 2,000.TM. (polyethylene oxide available 
from Petrolite Corporation), 24.0 grams of ELVAX 420.TM. (polyalkylene 
oxide available from E. I. DuPont), 24.0 grams of VERSAMID 744.TM. (a 
polyamide available from Henkle Inc.), 168.0 grams of iron-copper-copper 
iodide powder (Example IV), and 28.0 grams of LITHOL SCARLET.TM. pigment 
was mixed and ground in a Fitzmill Model J equipped with an 850 micrometer 
screen. After grinding, the mixture was dry blended first on a paint 
shaker and then on a roll mill. A small counter-rotating twin screw 
extruder (DAVO.TM.) was then used to melt mix the aforementioned mixture. 
A K-Tron twin screw volumetric feeder was employed in feeding the mixture 
to the extruder which had a barrel temperature of 150.degree. C. (flat 
temperature profile), and a screw rotational speed of 60 rpm with a feed 
rate of 10 grams per minute. The extruded strands were broken down into 
coarse particles by passing them through a Model J Fitzmill twice, first 
with an 850 micrometer screen, and then with a 425 micrometer screen. The 
coarse particles thus produced were micronized using an 8 inch Sturtevant 
micronizer and classified in a Donaldson classifier. The resulting red 
toner had a volume average particle diameter of 21 microns and a particle 
size distribution of 1.34 as determined by Coulter Counter measurements 
using Coulter Counter Model ZM, available from Coulter Electronics, Inc. 
The toner's saturation magnetic moment was then obtained by referencing its 
induced current per gram, 3 grams of toner sample to that of a 10 gram 
sample of nickel. For the toner of this Example, the saturation magnetic 
moment was 48.0 emu per gram. The toners conductivity was measured by 
preparing a pressed pellet of the toner at 2,000 pounds per square inch 
and using a conductivity meter unit. The conductivity of the toner of this 
example was 5.times.10.sup.-4 (ohm-cm).sup.-1. 
The above prepared toner was evaluated in a Xerox Corporation 4060.TM. 
printer. The toned images were transfixed onto paper with a transfix 
pressure of 4,000 psi. Print quality was evaluated from a checkerboard 
print pattern. The image optical density was measured with a standard 
integrating densitometer. Image fix was measured by the standardized 
scotch tape pull method, and was expressed as a percentage of the retained 
image optical density after the tape test relative to the original image 
optical density. Image smearing was evaluated qualitatively by hand 
rubbing the fused checkerboard print using a blank paper under an applied 
hand force, and viewing the surface cleanliness of unprinted and printed 
areas of the page. Image ghosting on paper was evaluated visually. For the 
above prepared toner, the image fix level was 74 percent, and no image 
smear and no image ghosting were observed in this machine testing for at 
least 2,000 prints. The color properties of a print were then measured 
using the Match-Scan II spectrometer, and for the toner of this example, 
the lightness was 54 units, the chroma was 82 units and the hue was 76 
units. 
EXAMPLE IX 
(COMATIVE) 
Synthesis of a colored toner composition containing a magnetic material 
such as iron with no coating 
A mixture of 108.0 grams of POLYWAX 2,000.TM. (polyethylene oxide available 
from Petrolite Corporation), 24.0 grams of ELVAX 420.TM. (polyalkylene 
oxide available from E. I. DuPont), 24.0 grams of VERSAMID 744.TM. 
(polyamide available from Henkle Inc.), 168.0 grams of iron powder 
(available from BASF as SICOPUR 4688.TM.), and 28.0 grams of LITHOL 
SCARLET.TM. pigment was mixed and ground in a Fitzmill Model J equipped 
with an 850 micrometer screen. After grinding, the mixture was dry blended 
first on a paint shaker and then on a roll mill. A small counter-rotating 
twin screw extruder (DAVO.TM.) was then used to melt mix the 
aforementioned mixture. A K-Tron twin screw volumetric feeder was employed 
in feeding the mixture to the extruder which had a barrel temperature of 
150.degree. C. (flat temperature profile), and a screw rotational speed of 
60 rpm with a feed rate of 10 grams per minute. The extruded strands were 
broken down into coarse particles by passing them through a Model J 
Fitzmill twice, first with an 850 micrometer screen, and then with a 425 
micrometer screen. The coarse particles thus produced were micronized 
using an 8 inch Sturtevant micronizer and classified in a Donaldson 
classifier. The resulting dull brownish toner had a volume average 
particle diameter of 21 microns and a particle size distribution of 1.34 
as determined by Coulter Counter measurements using Coulter Counter Model 
ZM, available from Coulter Electronics, Inc. 
The toner's (3 grams of sample) saturation magnetic moment was then 
obtained by referencing its induced current per gram to that of a 10 gram 
sample of nickel. For the toner of this Example, the saturation magnetic 
moment was 48.0 emu per gram. The toner's conductivity was measured by 
preparing a pressed pellet of the toner at 2,000 pounds per square inch 
and using a conductivity meter unit. The conductivity of the toner of this 
Example was 1.5.times.10.sup.-16 (ohm-cm).sup.-1. 
The above prepared toner was evaluated in a Xerox Corporation 4060.TM. 
printer. However, due to poor conductivity of the toner, images could not 
be developed. 
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.