Note: Descriptions are shown in the official language in which they were submitted.
CA 02677571 2009-09-03
FERROMAGNETIC NANOPARTICLES WITH HIGH MAGNETOCRYSTALLINE
ANISOTROPY FOR MICR INK APPLICATIONS
TECHNICAL FIELD OF THE DISCLOSURE
[0001] The present disclosure relates to a MICR inkjet ink comprising
stabilized
magnetic single-crystal nanoparticles, wherein the absolute value of the
magnetic anisotropy
of the magnetic nanoparticIes IK1 I is greater than or equal to 2 x 104 J/m3.
The magnetic
nanoparticle may be a ferromagnetic nanoparticle, such as FePt. The ink
includes a magnetic
material that minimizes the size of the particle, resulting in excellent
magnetic pigment
dispersion and dispersion stability, particularly in non-aqueous inkjet inks.
The smaller-sized
magnetic ink particles also maintain excellent magnetic properties, thereby
reducing the
amount of magnetic particle loading required in the ink.
BACKGROUND
[0002] Magnetic Ink Character Recognition (MICR) technology is well-known.
MICR inks contain a magnetic pigment or a magnetic component in an amount
sufficient to
generate a magnetic signal strong enough to be readable via MICR. Generally,
the ink is used
to print all or a portion of a document, such as checks, bonds, security
cards, etc. For
example, most checks exhibit an identification code area, usually at the
bottom of the check.
The characters of this identification code are usually MICR encoded. The
document may be
printed with a combination of MICR-readable ink and non-MICR-readable ink, or
with just
MICR-readable ink. The document thus printed is then exposed to an appropriate
source or
field of magnetization, at which time the magnetic particles become aligned as
they accept
and retain a magnetic signal. The document can then be authenticated by
passing it through a
reader device, which detects or "reads" the magnetic signal of the MICR
imprinted characters,
in order to authenticate or validate the document.
[0003] There are numerous challenges in developing a MICR inkjet ink_ First,
most
if not all, inkjet printers limit considerably the particle size of any
particulate components of
the ink, due to the very small size of the inkjet print head nozzle that
expels the ink onto the
substrate. The size of the inkjet head nozzles are generally on the order of
about 40 to 50
microns, but can be less than 10 microns. This small nozzle size dictates that
the particulate
matter contained in any inkjet ink composition intended for use in an inkjet
printer must be of
a very small particle size, in order to avoid nozzle clogging problems.
However, even when
the particle size is smaller than nozzle size, the particles can still
agglomerate, or cluster
together, to the extent that the size of the agglomerate exceeds the size of
the nozzle, resulting
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2
in the nozzle being blocked. Additionally, the particulate matter may be
deposited in the
nozzle during printing, thereby forming a crust that results in nozzle
blockage and/or
imperfect flow parameters.
100041 Another concern in the formulation of MICR inkjet inks is that the ink
must
be fluid, and not dry. Thus, an increase in pigment size causes a
corresponding increase in
density, thereby making it difficult to maintain the pigments in suspension or
dispersion
within a liquid ink composition.
[00051 MICR inks contain a magnetic material that provides the required
magnetic
properties. It is imperative that the magnetic material retains a sufficient
charge so that the
printed characters retain their readable characteristic and are easily
detected by the detection
device or reader. The magnetic charge retained by a magnetic material is known
as
"remanence." The "coercive force" of a magnetic material refers to the
magnetic field H,
which must be applied to a magnetic material in a symmetrical, cyclicly
magnetized fashion,
to make the magnetic induction B vanish. The coercivity of a magnetic material
is thus the
coercive force of the material in a hysterisis loop, whose maximum induction
approximates
the saturation induction. The observed remanent magnetization and the observed
coercivity
of a magnetic material depend on the magnetic material having some anisotropy
to provide a
preferred orientation for the magnetic moment in the crystal. Four major
anisotropy forces
determine the particle coercive force: magnetocrystalline anisotropy, strain
anisotropy,
exchange anisotropy, and shape anisotropy. The two dominant anisotropies are:
1) shape
anisotropy, where the preferred magnetic orientation is along the axis of the
magnetic crystal,
and 2) magnetocrystalline anisotropy, where the electron spin-orbit coupling
aligns the
magnetic moment with a preferred crystalline axis.
[0006] The magnetic material must exhibit sufficient rernanence once exposed
to a
source of magnetization, in order to generate a MICR-readable signal and have
the capability
to retain the same over time. Generally, an acceptable level of charge, as set
by industry
standards, is between 50 and 200 Signal Level Units, with 100 being the
nominal value,
which is defined from a standard developed by ANSI (the American National
Standards
Institute). A lesser signal may not be detected by the MICR reading device,
and a greater
signal may also not give an accurate reading. Because the documents being read
employ the
MICR printed characters as a means of authenticating or validating the
presented documents,
it is imperative that the MICR characters or other indicia be accurately read,
without skipping
or mis-reading any characters. Therefore, for purposes of MICR, remanence
should be at
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3
least a minimum of 20 emu/g. A higher remanence value corresponds to a
stronger readable
signal.
[0007] Remanence tends to increase as a function of particle size and the
density of
the magnetic pigment coating. Accordingly, when the magnetic particle size
decreases, the
magnetic particles tend to experience a corresponding reduction in remanence.
Achieving
sufficient signal strength thus becomes increasingly difficult as the magnetic
particle size
diminishes and the practical limits on percent content of magnetic particles
in the ink
composition are reached. A higher remanence value will require less total
percent magnetic
particles in the ink formula, improve suspension properties, and reduce the
likelihood of
settling as compared to an ink formula with higher percent magnetic particle
content.
[0008] Additionally, MICR inkjet inks must exhibit low viscosity, typically on
the
order of less than about 15 cP or on the order of about 2-8 cP at jetting
temperature (whereby
the jetting temperature ranges from about 25 C to about 140 C), in order to
function properly
in both drop-on-demand type printing equipment, such as thermal bubble jet
printers and
piezoelectric printers, and continuous type print mechanisms. The use of low
viscosity fluids,
however, adds to the concerns of successfully incorporating magnetic particles
into an ink
dispersion because particle settling will increase in a less viscous, thinner
fluid as compared
to a more viscous, thicker fluid.
[0009] Magnetite (iron oxide, Fe304) is a common magnetic material used in
MICR
inkjet inks. Magnetite has a low magnetocrystalline anisotropy, Kl, of -1.1 x
104 J/m3. An
acicular crystal shaped magnetite, in which one crystal dimension is much
larger than the
other, has an aspect ratio of the major to minor size axis of the single
crystal (D
major. ¨ minor, 0-/1)
f
2:1 or larger, helps to augment the magnetic remanence and coercivity
performance in inks.
Acicular magnetite is typically 0.6 x 0.1 micron in size along the minor and
major axis,
respectively, and has a large shape anisotropy (6/1). Typical loading of iron
oxide in inks is
about 20 to 40 weight percent. However, due to the larger sizes and aspect
ratio of acicular
crystal shaped magnetite particles, they are difficult to disperse and
stabilize into inks,
especially for use in inkjet printing. Moreover, spherical or cubic magnetites
are smaller in
size (less than 200 nm in all dimensions), but have low shape anisotropy
(Dmajor/Dminor) of
about 1. Consequently, because of the low overall anisotropy, spherical or
cubic magnetite
have lower magnetic remanence and coercivity, and loadings higher than 40
weight percent
are often needed to provide magnetic performance. Thus, while spherical and
cubic
magnetite have the desired smaller particle size of less than 200 nm in all
dimensions, the
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much higher loading requirement also makes them very difficult to disperse and
maintain a
stable dispersion. Moreover, such high loadings of the inert, non-melting
magnetic material
interfere with other ink properties, such as adhesion to the substrate and
scratch resistance.
Consequently, this worsens the suitability of magnetites for inkjet printing
inks-
[0010] Additionally, because magnetite has a specific gravity of approximately
7,
magnetite has a natural tendency to settle to the bottom of a fluid ink
composition. This
results in a non-homogenous fluid having an iron oxide-rich lower layer and an
iron oxide-
deficient upper layer. Moreover, suitable inkjet oxides must generally be
hydrophilic in
nature in order to provide good dispersion characteristics, and to provide
good emulsion
properties. The latter parameters relate directly to the ability of the
magnetic particle to
exhibit minimum settling and to further demonstrate the proper wetting of the
magnetic
particle with the other water-soluble ingredients generally present in an
inkjet ink
composition_
[0011] The problems commonly associated with using iron oxide in MICR inkjet
inks have been addressed in several different ways. For example, using a
combination of
surfactants in conjunction with a very small particle size metal oxide
component, aimed at
maintaining a useful suspension or dispersion of the magnetic component within
the ink
composition, is known. Another means of achieving an inkjet ink suitable for
use in inkjet
printers, and also for generating MICR-readable print, is to coat the metal
magnetic material
with a specific hydrophilic coating to help retain the particulate magnetic
metal in suspension.
[0012] Still yet, another type of ink used for MICR inkjet printing is
xFerroneTm
(iron complex pigment) inks, which are aqueous inks commercialized by 07
Productivity
Systems, Inc. (Versalnkrm). These inks are compatible with HP , Canon ,
Lexmark , Dell
and Epson printers, and have a variety of uses, such as, for example,
ensuring reliable
scanning of checks, and eliminating delays at a store checkout line. However,
these inks do
not exhibit the properties of including a reduce sized magnetic material
particle that has
excellent magnetic pigment dispersion and dispersion stability, while
maintaining excellent
magnetic properties, and a reduced particle loading requirement. This is
because the
major/minor axis of the magnetic particles used in such conventional inks must
have at least a
2:1 ratio, and therefore, the particle size of the acicular magnetite is 0.6
micron for the major
axis. This results in poor dispersion and poor dispersion stability.
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5
REFERENCES
[0013] U.S. Patent No. 4,859,550 describes an electrophotographic process that
comprises generating a latent image; developing the image with a toner
composition
comprised of resin particles, magnetite particles and an additive component
comprised of an
aliphatic hydrocarbon or a polymeric alcohol; and subsequently providing the
developed
image with magnetic ink characters thereon to a reader/sorter device, whereby
toner offsetting
and image smearing is minimized in the device.
[0014] U.S. Patent No. 5,124,217 describes a MICR process, wherein an
electrophotographic process enables substantially tamperproof images,
including the
generation of a latent image. It also describes developing the image with a
toner composition
comprised of resin particles, magnetite particles, and a colored organic
soluble dye, a colored
organic insoluble dye, or the salts thereof, and an optional additive
component comprised of
an aliphatic hydrocarbon or a polymeric alcohol.
[0015] U.S. Patent Nos. 5,506,079 and 5,597,405 describe an organic magnetic
composition comprising an alkali-metal-doped tetraazaporphyrin derivative or
an alkali-
metal-doped porphyrin derivative for use in magnetic toners and inks.
[0016] U.S. Patent Nos. 5,543,219 and 6,187,439 describe encapsulated
particles,
such as magnetic particles, colored pigments, or carbon black, with high
chemical affinity for
ink vehicles. The encapsulated particles are suitable for printing inks, as
well as for magnetic
recording systems, such as audio and video tapes and magnetic storage disks,
wherein the
encapsulated particles are magnetic particles.
[0017] U.S. Patent No. 5,976,748 describes a magnetic toner for a MICR printer
containing a binder resin and a magnetic powder, prepared in such a way that
the magnetic
powder includes a first magnetic powder having a residual magnetization value
within a range
of 24 to 40 emu/g and a second magnetic powder having a residual magnetization
value
within a range of 1 10 24 em.u/g (but exclusive of 1 elnu/g), and the residual
magnetization
value of the magnetic toner for a MICR printer is within a range of 7.0 to 20
emu/g (but
exclusive of 7.0 emu/g).
[0018] U.S. Patent No. 6,248,805 describes specific core-shell binders and
magnetic
additives for use in 'inkjet printing ink compositions.
[0019] U.S. Patent No. 6,610,451 describes development systems and methods for
developing, using magnetic toners, developers used in development systems, as
well as the
toner used in developers for magnetic ink character recognition printing_
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[0020] U.S. Patent No_ 6,746,527 describes an aqueous inkjet ink composition
for
MICR applications, including a metal oxide pre-dispersion combined with an
aqueous inkjet
ink composition, wherein the metal oxide pre-dispersion contains a metal oxide
pigment or a
very small particle, and at least one surfactant. Particularly, the surfactant
component is a
combination of an anionic surfactant and an anionic-nonionic surfactant, or a
combination of
other types of surfactants.
[00211 U.S. Patent No. 6,764,797 describes a toner composition for MICR
applications, including at least a binder resin, magnetite particles
comprising a mixture of
granular magnetite and acicular magnetite, and a wax, wherein a ratio by
weight of the
acicular magnetite in the magnetite particles is 0.1-0.5 to the granular
magnetite of 1.0, the
magnetite particles are contained in an amount of 15-50 weight percent, the
granular
magnetite has residual magnetization of 5-15 emu/g and saturation
magnetization of 70-95
emu/g, and the acicular magnetite has residual magnetization of 20-50 emu/g
and saturation
magnetization of 70-95 exnu/g.
10022] U.S. Patent Nos_ 6,767,396 and 6,727,579 describe a process for
preparing
an aqueous inkjet ink composition for MICR applications, by preparing a metal
oxide pre-
dispersion combined with an aqueous inkjet ink composition, wherein the metal
oxide pre-
dispersion contains metal oxide pigments, or particles of a very small
particle size, and the
ink exhibits high remanence of at least 20 emu/g. The metal oxide particles
may be coated
with a hydrophilic coating, and the pre-dispersion may contain at least one
surfactant to aid in
the dispersion of the metal oxide particles. Special processing involving the
use of
conventional and non-conventional grinding techniques and various filtration
techniques
enhances the compatibility of the MICR inkjet ink with the inkjet equipment.
[00231 U.S. Patent No. 7,255,433 describes a multiple pass printing process
for
generating MICR-readable indicia asing a MICR inkjet ink composition with a
magnetic
pigment loading less than that needed to generate the nominal signal level
according to the
ANSI standard with single pass printing. It also describes a printed
substrate, prepared by the
process, which bears MICR-readable indicia having at least two layers of the
MICR inkjet ink
composition and which demonstrates a MICR signal level of greater than or
equal to the
nominal signal value according to the ANSI standard.
[0024] U.S. Patent Application Publication No. 2006/0246367 describes a
magnetic
toner composition including a carbon nanofoam and a polymer, a magnetic ink
composition
including a carbon nanofoain and a fluid carrier; and a xerographic process
that includes
CA 02677571 2012-05-14
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depositing a toner composition on a latent electrostatic image to form a toner
image. It also
describes MICR processes including providing a substrate having a magnetic
composition
including a carbon nanofoam applied thereto to form at least one recognizable
character, and
scanning the substrate with a reading device.
[0025] Elkins et al., Monodisperse face-centred tetragonal FePt nanoparticles
with
giant coercivity, J. Phys. D. App!. Phys. (38) pp. 2306-09 (2005), describes
preparation of
monodisperse fct-phase FePt nanoparticles with high magnetic anisotropy and
high coercivity
by a new heat treatment route and methods of preparing magnetic particles with
magnetocrystalline anisotropy greater than 2x104 J/m3.
100261 Luborsky et al., High Coercive Materials: Development of Elongated
Particle Magnets, J. App. Phys., Supp to Vol. 32 (3), pp. 171S-184S (1961),
reviews the
development of permanent magnet materials.
[0027] Watari et al., Effect of Crystalline Properties on Coercive Force in
Iron
Acicular Fine Particles, J. of Mater. Sci., 23, pp. 1260-64 (1988),
investigates the orientation
relation of iron acicular fine particles and its size dependence, and the
relationship between
crystallographic properties and magnetic properties. Watari et al. also
describe methods of
preparing magnetic particles with magnetocrystalline anisotropy greater than
2x104 J/m3
[00281 Tzitzios et al., Synthesis and Characterization of Llo FePt
Nanoparticles
from Pt (Au, Ag)/ y -Fe203 Core-Shell Nanoparticles, Adv. Mater. 17, pp. 2188-
92 (2005),
describes a method of synthesis and the characterization of Llo FePt
nanoparticles from Pt
(Au, Ag)/i -Fe203 core-shell nanoparticles.
100291 Shah et al., Int. J. of Modern Phys. B. Vol 20 (1), 37-47 (2006);
Bonder et al.
J. Magnetism and Magnetic Materials, 311(2), 658-664; Baker et al., Mat. Res.
Soc. Symp.
Proc. Vol 746, Q4.4.1-Q4.4.6 (2003); Li et al., Journal of Applied Physics 99,
08E911 (2006)
all describe methods of preparing magnetic particles with magnetocrystalline
anisotropy
greater than 2x104 J/m3.
[0030] The appropriate components and process aspects of each of the foregoing
may be selected for the present disclosure in embodiments thereof.
SUMMARY
100311 The present disclosure relates to an ink that is suitable for MICR
inkjet ink
printing and embodies all of the above-listed advantages. The ink includes
single crystal
magnetic nanoparticles, wherein the size of the nanoparticles is from about 10
nm to about
CA 02677571 2011-08-18
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300 nm, and the absolute value of the magnetocrystalline anisotropy,11(11, is
greater than or
equal to 2 x 104 J/m3. The magnetic nanoparticles may be bimetallic or
trimetallic, and have
low aspect ratio and exhibit better dispersion and stability. In one
embodiment, the
nanoparticles are single crystal ferromagnetic nanoparticles. Such single
crystal
ferromagnetic nanoparticles, including the smaller size non-acicular
particles, have very high
magnetic shape anisotropy. Accordingly, these single crystal ferromagnetic
nanoparticles
demonstrate the requisite high remanance and coercivity suitable for MICR ink
applications,
and particularly, inkjet ink applications.
[0032] Various magnetic nanoparticles may be used in the inks according to the
present disclosure. For example, FePt nanoparticles are suitable for MICR
inkjet ink
application because they exhibit high magnetic anisotropy and, therefore, high
coercivity.
FePt exists in two phases: a face-centered cubic (fcc) phase and a face-
centered tetragonal
(fct) phase. The fct phase FePt has very high magnetocrystalline anisotropy.
The fct phase
FePt nanoparticle can be synthesized from the fcc phase FePt nanoparticle,
according to, for
example, the method taught by Elkins et al., Monodisperse face-centred
tetragonal FePt
nanoparticles with giant coercivity, J. Phys. D: Appl. Phys. pp. 2306-09
(2005), or by Tzitios
et at., Synthesis and Characterization of Ll 0 FePt Nanoparticles from Pt (Au,
Ag)/ y -Fe203
Core-Shell Nanoparticles, Adv. Mater. 17, pp. 2188-92 (2005). The MICR inkjet
ink of the
present disclosure includes a magnetic material that requires smaller sized
magnetic particles,
resulting in excellent magnetic pigment dispersion and dispersion stability,
particularly in
non-aqueous inkjet inks. Moreover, the smaller sized magnetic particles of the
MICR inkjet
ink also maintains excellent magnetic properties, thereby reducing the amount
of magnetic
particle loading required in the ink.
[0032a] In accordance with an aspect, there is provided an ink comprising:
a carrier;
an optional colorant; and
stabilized magnetic single-crystal nanoparticles,
wherein an absolute value of the magnetic anisotropy of the magnetic
nanoparticles is greater than or equal to 2 x 104 J/m3.
[0032b] In accordance with another aspect, there is provided an ink
comprising:
a carrier;
an optional colorant; and
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stabilized magnetic single-crystal nanoparticles having single crystal
domains with a domain size that is at least 10 nm, wherein
an absolute value of the magnetic anisotropy of the magnetic nanoparticles
is greater than or equal to 2 x 104 J/m3.
EMBODIMENTS
[0033] In general, the present disclosure relates to an ink including a
magnetic
nanoparticle exhibiting large anisotropy, dispersed in a carrier medium. The
ink may
additionally include one or more resins, one or more colorants, and/or one or
more additives.
In one embodiment, the magnetic nanoparticles are metallic nanoparticles. In
another
embodiment, the magnetic nanoparticles are single crystal ferromagnetic
nanoparticles. The
inks are suitable for use in various applications, including MICR
applications. In addition,
the printed inks may be used for decoration purposes, even if the resulting
inks do not
sufficiently exhibit coercivity and remanence suitable for use in MICR
applications. The ink
of the present disclosure exhibits stability, dispersion properties and
magnetic properties that
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are superior to that of an ink including magnetite. The ink composition is now
described in
detail.
[0034] This disclosure is not limited to particular embodiments described
herein,
and some components and processes may be varied by one of ordinary skill in
the art, based
on this disclosure. The terminology used herein is for the purpose of
describing particular
embodiments only, and is not intended to be limiting.
100351 In this specification and the claims that follow, singular forms such
as "a,"
"an," and "the" include plural forms unless the content clearly dictates
otherwise.
[0036] In this specification and the claims that follow, "ink" is also
referred to as
"ink composition," and vice versa.
The Magnetic Material
100371 Suitable magnetic material for use in the present disclosure include
single
crystal nanoparticles exhibiting large anisotropy. Used herein, "large
anisotropy" is defined
as the absolute value of the magnetocrystalline anisotropy of a particle,
wherein the absolute
value is equal to or greater than 2 x 104 J/m3. Suitable magnetic materials
have K1 values
from about 2 x 104 J/m3 to about 5 x 107 J/m3, such as from about 5 x 104 J/m3
to about 5 x
106 J/m3, or from about 7 x 104 J/m3 to about 4 x 106 J/m3, although materials
with higher K1
values are also suitable. In embodiments, the single crystal nanoparticle may
be a magnetic
metallic nanoparticle, or a ferromagnetic nanoparticle with a large anisotropy
that includes,
for example, Co, Fe (cubic), and Mn among others. Additionally, the magnetic
nanoparticles
may be bimetallic or trimetallic, or a mixture thereof. Examples of suitable
bimetallic
magnetic nanoparticles include, without limitation, CoPt, fcc phase FePt, fct
phase FePt,
FeCo, MnAl, MnBi, CoO=Fe203, Ba0.6Fe203, mixtures thereof, and the like. In
another
embodiment, the magnetic nanoparticle is fct phase FePt. Examples of
trimetallic
nanoparticles can include, without limitation tri-mixtures of the above
magnetic
nanoparticles, or core/shell structures that form trimetallic nanoparticles
such as Co-covered
fct phase FePt.
100381 The magnetic nanoparticles may be prepared by any method known in the
art, including ball-milling attrition of larger particles (a common method
used in nano-sized
pigment production), followed by annealing. The annealing is generally
necessary because
ball milling produces amorphous nanoparticles, which need to be subsequently
crystallized
into the required single crystal form. The nanoparticles can also be made
directly by RF
plasma. Appropriate large-scale RF plasma reactors are available from Tekna
Plasma
CA 02677571 2009-09-03
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Systems. The nanoparticles can also be made by a number of in situ methods in
solvents,
including water.
[0039] The average particle size of the magnetic nanoparticles may be, for
example,
about 10 rim to about 300 run in size in all dimensions. They can be of any
shape including
spheres, cubes and hexagons. In one embodiment, the nanoparticles are about 10
nm to about
500 rim in size, such as from about 50 ntn to about 300 rim, or from 75 inn to
about 250 nm,
although the amount can be outside of these ranges. Herein, "average" particle
size is
typically represented as d50, or defined as the median particle size value at
the 50th percentile
of the particle size distribution, wherein 50% of the particles in the
distribution are greater
than the d50 particle size value, and the other 50% of the particles in the
distribution are less
than the d50 value_ Average particle size can be measured by methods that use
light scattering
technology to infer particle size, such as Dynamic Light Scattering. The
particle diameter
refers to the length of the pigment particle as derived from images of the
particles generated
by Transmission Electron Microscopy (TEM).
10040] The magnetic nanoparticles may be in any shape. Exemplary shapes of the
magnetic nanoparticles can include, for example, without limitation, needle-
shape, granular,
globular, atnorphorous shapes, and the like.
100411 The ratio of the major to minor size axis of the single nanocrystal
(Dnnajor/Dminor) can be less than about 4:1, such as from about less than
about 3:2, or less than
about 2:1.
[0042] The loading requirements of the magnetic nanoparticles in the ink may
be
from about 0.5 weight percent to about 15 weight percent, such as from about 5
weight
percent to about 10 weight percent, or from about 6 weight percent to about 8
weight percent,
although the amount can be outside of these ranges.
[00431 The magnetic nanoparticle can have a remanence of about 20 emu/g to
about
100 etnu/g, such as from about 40 emu/g to about 80 emu/g, or about 50 emu/g
to about 70
emu/g, although the amount can be outside of these ranges.
[0044] The coercivity of the magnetic nanoparticle can be, for example, about
200
Oersteds to about 50,000 Oersteds, such as from about 1,000 Oersteds to about
40,000
Oersteds, or from about 10,000 Oersteds to about 20,000 Oersteds, although the
amount can
be outside of these ranges.
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[0045] The magnetic saturation moment may be, for example, about 20 emu/g to
about 150 emu/g, such as from about 30 emu/g to about 100 emu/g, or from about
50 emu/g
to about 80 emu/g, such as about 70 emu/g, although the amount can be outside
of these
ranges.
[0046] Examples of suitable magnetic nanoparticle compositions with large
magnetocrystalline anisotropy, Kl, are shown in Table 1. Table 1 also shows a
reference
magnetite. Note that actual coercivity obtained for nanocrystalline materials
may be lower
than the maximum coercivity shown here, because coercivity is strongly size-
dependent.
Peak coercivity for Fe and Co occurs when the particles are about 20 nm in
size, and peak
coercivity for CoO=Fe203 occurs when the particles are about 30 nm in size.
Another suitable
magnetic material with high magnetocrystalline anisotropy include, for
example, CoPt, with
K1 value of 4.9 x 106 J/m3.
Table 1
Magnetocrystalline Maximum Coercivity
Anisotropy (104J/m3) (Oersteds)
MICR Toner Requirement 22 2300
Reference Magnetitef 2 1.1 460
(Fe304 or FeO= Fe203)
FePt (face-centered tetragonal)' 3 6603 29000
Fe (cubic)ref 2 4 1000
COref 2 40 2100
Co0' Fe203ref 2 25 4200
Ba0* 6Fe203ref 2 33 4500
mnAiref 2 100 6000
mnBiref 2 116 12000
Ref 2: F.E. Luborsky, J. Appl. Phys., Supp. to Vol. 32 (3), 171S-184S (1961)
and the references therein.
Ref 3: V. Tzitzios et al., Adv. Mater. 17, 2188-92 (2005).
[0047] Examples of magnetic nanocrystals with high magnetocrystalline
anisotropy
that have been prepared in the literature are shown in Table 2. Any of the
particles shown
below are suitable for MICR ink applications.
CA 02677571 2009-09-03
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Table 2
Particle
Chemistry Saturation
RemanentMagnetocrystallineCoercivity
Size (mu) Moment Moment
Anistotropy
(Crystal
(Oerste ds)
(emu/g) (cmu/g) (104 J/m3)
Structure)
MICR Toner 10 to 330 No specific > 20
> 300 >
Requirement requirement
FePt (fct)r 4 8 cubic >40 30
30,000 660
FePt (fct)'f 4 15 cubic > 50 40
20,000 660
Fe (bcc)'il 20 x 20 x 200 145 72.7
1540 4.81"cf 2
fct = face-centered tetragonal crystal structure; bcc= body-centered cubic
crystal structure
Ref : F. Watari, et al., J. Mater. Sci., 23, pp. 1260-64 (1988).
Ref 4: K. Elkins, et al., J. Phys. D. Appl. Phys., 38, pp_ 2306-09 (2005).
[0048i Nevertheless, a large inherent magnetocrystalline anisotropy of a
material
does not ensure that the material will have a high remanence or high
coercivity that will
render the material suitable for MICR applications. Similarly, FePt alloys, Fe
or Co do not
necessarily have the required remanence or coercivity. A particular material
is generally
suitable for MICR application only if the material has both: 1) a large
inherent
magnetocrystalline anisotropy, and 2) single crystal domains where the domain
size is at least
about 10 rim (the exact minimum size limit depends on the material).
[0049] Additionally, it is possible to produce an ink containing a bimetallic
magnetic nanoparticle whose absolute value of the magnetocrystalline
anisotropy K 1 is
greater than 2 x 104 J/m3, and is at least one of FeCo or Fe203. This may be
achieved by any
means known in the art. For example, an ink containing FePt crystalline
nanoparticles may
be mixed with an ink containing Fez03. Alternatively, an FePt crystalline
nanoparticles and
Fe203 may be added into the ink during ink synthesis. Such mixtures thus
combine the
relatively inexpensive Fe203 with the improved magnetic and dispersion
properties of FePt
crystalline nanoparticles, to produce a MICR inkjet ink. In such mixtures, the
ratio of
magnetic nanoparticles to FeCo or Fe203 is about 0.1:99.9 or reverse, such as
about 10:90, or
about 30:70, or about 50:50. For such mixtures, the loading requirement is,
for example,
from about 0.5 weight percent to about 15 weight percent of the ink, such as
from about 2
weight percent to about 10 weight percent, or from 5 weight percent to about 8
percent,
although the amount can be outside of these ranges.
Carrier Material
[0050] The ink composition also includes a carrier material, or a mixture of
two or
more carrier materials. The carrier material can vary, for example, depending
upon the
CA 02677571 2012-05-14
13
specific type of ink composition. For example, an aqueous inkjet ink
composition can use
water, or a mixture of water and one or more other solvents, as a suitable
carrier material.
Other ink jet ink compositions can use one or more organic solvents as a
carrier material, with
or without water.
[0051] In the case of a solid (or phase change) inkjet ink composition, the
carrier
can include one or more organic compounds. The carrier for such solid ink
compositions is
typically solid at room temperature (about 20 C to about 25 C), but becomes
liquid at the
printer operating temperature for ejecting onto the print surface. Suitable
carrier materials for
solid ink compositions can thus include, for example, amides, including
diamides, triamides,
tetra-amides, and the like. Suitable triamides include, for example, those
disclosed in U.S.
Patent No. 6,860,930. Other suitable amides, such as fatty amides including
monoamides,
tetra-amides, and mixtures thereof, are disclosed in, for example, U.S. Patent
Nos. 4,889,560,
4,889,761, 5,194,638, 4,830,671, 6,174,937, 5,372,852, 5,597,856, and
6,174,937, and British
Patent No. GB 2 238 792. In embodiments where an amide is used as a carrier
material, a
triamide is particularly useful because triamides are believed to have
structures that are more
three-dimensional as compared to other amides such as diamides and
tetraamides.
[0052] Other suitable carrier materials that can be used in the solid ink
compositions include, for example, isocyanate-derived resins and waxes, such
as urethane
isocyanate-derived materials, urea isocyanate-derived materials, urethane/urea
isocyanate-
derived materials, mixtures thereof, and the like.
[0053] Additional suitable solid ink carrier materials include paraffins,
microcrystalline waxes, polyethylene waxes, ester waxes, amide waxes, fatty
acids, fatty
alcohols, fatty amides and other waxy materials, sulfonamide materials,
resinous materials
made from different natural sources (such as, for example, tall oil rosins and
rosin esters), and
many synthetic resins, oligomers, polymers and copolymers, such as
ethylene/vinyl acetate
copolymers, ethylene/acrylic acid copolymers, ethylene/vinyl acetate/acrylic
acid copolymers,
copolymers of acrylic acid with polyamides, and the like, ionomers, and the
like, as well as
mixtures thereof. One or more of these materials can also be employed in a
mixture with a
fatty amide material and/or an isocyanate-derived material.
[0054] The ink carrier in a solid ink composition can be present in any
desired or
effective amount. For example, the carrier can be present in an amount of
about 0.1 to about
CA 02677571 2011-08-18
14
99.9 weight percent such as about 50 to about 99.9 weight percent, such as
about 50 to about
98 weight percent, or about 90 to about 95 weight percent, although the amount
can be
outside of these ranges.
[0055] In the case of a radiation (such as ultraviolet light) curable ink
composition,
the ink composition comprises a carrier material that is typically a curable
monomer, curable
oligomer, or curable polymer, or a mixture thereof. The curable materials are
typically liquid
at 25 C. The curable ink composition can further include other curable
materials, such as a
curable wax or the like, in addition to the colorant and other additives
described above. The
term "curable" refers, for example, to the component or combination being
polymerizable,
that is, a material that may be cured via polymerization, including, for
example, free radical
routes, and/or in which polymerization is photoinitiated though use of a
radiation sensitive
photoinitiator. Thus, for example, the term "radiation curable" refers is
intended to cover all
forms of curing upon exposure to a radiation source, including light and heat
sources and
including in the presence or absence of initiators. Example radiation curing
routes include,
but are not limited to, curing using ultraviolet (UV) light, for example
having a wavelength of
200-400 nm or more rarely visible light, such as in the presence of
photoinitiators and/or
sensitizers, curing using e-beam radiation, such as in the absence of
photoinitiators, curing
using thermal curing in the presence or absence of high temperature thermal
initiators (and
which are generally largely inactive at the jetting temperature), and
appropriate combinations
thereof.
[0056] Suitable radiation- (such as UV-) curable monomers and oligomers
include,
but are not limited to, acrylated esters, acrylated polyesters, acrylated
ethers, acrylated
polyethers, acrylated epoxies, urethane acrylates, and pentaerythritol
tetraacrylate. Specific
examples of suitable acrylated oligomers include, but are not limited to,
acrylated polyester
oligomers, such as CN2262 (Sartomer Co.), EB 812 (Cytec Surface Specialties),
EB 810
(Cytec Surface Specialties), CN2200 (Sartomer Co.), CN2300 (Sartomer Co.), and
the like,
acrylated urethane oligomers, such as EB270 (UCB Chemicals), EB 5129 (Cytec
Surface
Specialties), CN2920 (Sartomer Co.), CN3211 (Sartomer Co.), and the like, and
acrylated
epoxy oligomers, such as EB 600 (Cytec Surface Specialties), EB 3411 (Cytec
Surface
Specialties), CN2204 (Sartomer Co.), CN110 (Sartomer Co.), and the like; and
pentaerythritol tetraacrylate oligomers, such as SR399LV (Sartomer Co.) and
the like.
Specific examples of suitable acrylated monomers include, but are not limited
to,
polyacrylates, such as trimethylol propane triacrylate, pentaerythritol
tetraacrylate,
pentaerythritol triacrylate, dipentaerythritol pentaacrylate, glycerol propoxy
triacrylate, tris(2-
hydroxyethyl) isocyanurate triacrylate, pentaacrylate ester, and the like,
epoxy acrylates,
CA 02677571 2009-09-03
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urethane acrylates, amine acrylates, acrylic acrylates, and the like. Mixtures
of two or more
materials can also be employed as the reactive monomer. Suitable reactive
monomers are
commercially available from, for example, Sartomer Co., Inc., Henkel Corp.,
Radcure
Specialties, and the like. In embodiments, the at least one radiation curable
oligomer and/or
monomer can be cationically curable, radically curable, or the like.
[00571 The curable monomer or oligomer in embodiments is included in the ink
in
an amount of, for example, about 20 to about 90 weight percent of the ink,
such as about 30
to about 85 weight percent, or about 40 to about 80 weight percent, although
the amount can
be outside of these ranges. In embodiments, the curable monomer or oligomer
has a viscosity
at 25 C of about 1 to about 50 cP, such as about 1 to about 40 cP or about 10
to about 30 cP,
although the amount can be outside of these ranges. In one embodiment, the
curable
monomer or oligomer has a viscosity at 25 C of about 20 cP. Also, in some
embodiments, it
is desired that the curable monomer or oligomer is not a skin irritant, so
that printed images
using the ink compositions are not irritable to users.
[0058] In other embodiments, the ink composition which comprises an aqueous
liquid vehicle and the magnetic single crystal nanoparticles disclosed herein.
The liquid
vehicle can consist solely of water, or it can comprise a mixture of water and
a water soluble
or water miscible organic component, such as ethylene glycol, propylene
glycol, diethylene
glycols, glycerine, dipropylene glycols, polyethylene glycols, polypropylene
glycols, amides,
ethers, urea, substituted ureas, carboxylic acids and their salts, esters,
alcohols,
organosulfides, organosulfoxides, sulfones (such as sulfolane), alcohol
derivatives, carbitol,
butyl carbitol, cellusolve, tripropylen.e glycol monomethyl ether, ether
derivatives, amino
alcohols, ketones, N-methylpyrrolidinone, 2-pyrrolidinone,
cyclohexylpyrrolidone,
hydroxyethers, amides, sulfoxides, lactones, polyelectrolytes, methyl
sulfonylethanol,
imidazole, betaine, and other water soluble or water miscible materials, as
well as mixtures
thereof.
[0059] In other embodiments encompassing non-aqueous inks, the magnetic single
crystal nanoparticles can be used in solvent-borne inks such as petroleum-
based inks that
include aliphatic hydrocarbons, aromatic hydrocarbons, and mixtures thereof,
environmentally friendly soy and vegetable oil-based inks, linseed oil-based
inks and other
ink-based vehicles derived from natural sources_ Other examples of ink
vehicles for magnetic
single crystal nanoparticles include isophthalic alkyds, higher order alcohols
and the like_ In
CA 02677571 2009-09-03
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still other embodiments, the magnetic single crystal nanoparticles can be
applied towards inks
used in relief, gravure, stencil, and lithographic printing.
Binder Resin
[0060] The ink composition according to the present disclosure may also
include
one or more binder resins. Additionally, a cross-linking structure may be
partly introduced to
a binder resin in order to improve the stability during storage, the shape-
retaining property, or
the durability of a toner if an amount of the cross-linking part (amount of
gel) can be about 10
weight percent of the ink or lower, or about 0.1 to about 10 weight percent,
although the
amount can be outside of these ranges.
[0061] The binder resin may be any suitable agent. Suitable binder resins
include,
without limitation, a maleic modified rosin ester (trademark Beckacite 4503
resin from
Arizona chemical company), phenolics, maleics, modified phenolics, rosin
ester, modified
rosin, phenotic modified ester resins, rosin modified hydrocarbon resins,
hydrocarbon resins,
terpene phenolic resins, terpene modified hydrocarbon resins, polyarnide
resins, tall oil rosins,
polyterpene resins, hydrocarbon modified terpene resins, acrylic and acrylic
modified resins
and similar resins or rosin known to be used in printing inks, coatings and
paints, and the like.
[0062] Other suitable binder resins include, without limitation, thermoplastic
resins,
homopolymers of styrene or substituted styrenes such as polystyrene,
polychloroethylene, and
polyvinyltoluene; styrene copolymers such as styrene - p-chlorostyrene
copolymer, styrene -
propylene copolymer, styrene - vinyltoluene copolymer, styrene -
vinylnaphthalene
copolymer, styrene - methyl acrylate copolymer, styrene - ethyl acrylate
copolymer, styrene -
butyl acrylate copolymer, styrene - octyl acrylate copolymer, styrene - methyl
methacrylate
copolymer, styrene - ethyl methacrylate copolymer, styrene - butyl
methacrylate copolymer,
styrene - methyl a-chloromethacrylate copolymer, styrene - acrylonitrile
copolymer, styrene -
vinyl methyl ether copolymer, styrene - vinyl ethyl ether copolymer, styrene -
vinyl methyl
ketone copolymer, styrene - butadiene copolymer, styrene - isoprene copolymer,
styrene -
acrylonitrile - indene copolymer, styrene - maleic acid copolymer, and styrene
- maleic acid
ester copolymer; polymethyl methacrylate; polybutyl methacrylate; polyvinyl
chloride;
polyvinyl acetate; polyethylene; polypropylene; polyester; polyvinyl butyral;
polyacrylic resin;
rosin; modified rosin; terpene resin; phenolic resin; aliphatic or aliphatic
hydrocarbon resin;
aromatic petroleum resin; chlorinated paraffin; paraffin wax, and the like.
These binder
resins can be used alone or in combination.
CA 02677571 2011-08-18
17
[0063] The molecular weight, molecular weight distribution, cross-linking
degree and
other properties of each of the above binder resins are selected in accordance
with the desired
melt viscosity of the ink to be obtained.
Colorants
[0064] The MICR ink according to the present disclosure may be produced as a
colored ink by adding a colorant during ink production. Alternatively, a non-
MICR colored ink
may be printed on a substrate during a first pass, followed by a second pass,
wherein a MICR
ink that is lacking a colorant is printed directly over the colored ink, so as
to render the colored
ink MICR-readable. In such instance, the order in which the two inks are
printed are
interchangeable. This can be achieved through any means known in the art. For
example, each
ink can be stored in a separate reservoir. The printing system delivers each
ink separately to the
substrate, and the two inks interact. The inks may be delivered to the
substrate simultaneously
or consecutively. Any desired or effective colorant can be employed in the ink
compositions,
including pigment, dye, mixtures of pigment and dye, mixtures of pigments,
mixtures of dyes,
and the like. The magnetic single crystal nanoparticles may also, in
embodiments, impart some
or all of the colorant properties to the ink composition.
[0065] Suitable colorants for use in the MICR ink according to the present
disclosure
include, without limitation, carbon black, lamp black, iron black,
ultramarine, Nigrosine dye,
Aniline Blue, Du Pont Oil Red, Quinoline Yellow, Methylene Blue Chloride,
Phthalocyanine
Blue, Phthalocyanine Green, Rhodamine 6C Lake, Chrome Yellow, quinacridone,
Benzidine
Yellow, Malachite Green, Hansa Yellow G, Malachite Green hexalate, oil black,
azo oil black,
Rose Bengale, monoazo pigments, disazo pigments, trisazo pigments, tertiary
ammonium salts,
metallic salts of salicylic acid and salicylic acid derivatives, Fast Yellow
G, Hansa Brilliant
Yellow 5GX, Disazo Yellow AAA, Naphthol Red HFG, Lake Red C, Benzimidazolone
Carmine HF3C, Dioxazine Violet, Benzimidazolone Brown HFR, Aniline Black,
titanium oxide,
Tartrazine Lake, Rhodamine 6G Lake, Methyl Violet Lake, Basic 6G Lake,
Brilliant Green
lakes, Hansa Yellow, Naphtol Yellow, Watching Red, Rhodamine B, Methylene
Blue, Victoria
Blue, Ultramarine Blue, and the like.
[0066] The amount of colorant can vary over a wide range, for instance, from
about
0.1 to about 50 weight percent, or from about 3 to about 20 weight percent,
and combinations of
colorants may be used.
Additional Additives
[0067] The MICR inkjet ink may further contain one or more additives for their
known
purposes. For example, suitable additives include, a particulate such as
colloidal
CA 02677571 2009-09-03
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silica; a wax; a surfactant; a dispersant; a humectant; a cross-linking agent;
a stabilizer; a
thickening agent; a gelatinizing agent; a defoaming agent and an initiator for
photopolymerization.
[0068] One or more waxes may be added to the MICR inkjet ink in order to raise
the image density and to effectively prevent the offset to a reading head and
the image
smearing. The wax can be present in an amount of, for example, from about 0.1
to about 10
weight percent, or from about 1 to about 6 weight percent based on the total
weight of the ink
composition, although the amount can be outside of these ranges. Examples of
suitable
waxes include, but are not limited to, polyolefin waxes, such as low molecular
weight
polyethylene, polypropylene, copolymers thereof and mixtures thereof. Other
examples
include a polyethylene wax, a polypropylene wax, a fluorocarbon-based wax
(Teflon), or
Fischer-Tropsch wax, although other waxes can also be used. The wax may, for
example,
help prevent offset to a reading head and image smearing.
[0069] The ink composition can also optionally contain an antioxidant. The
optional antioxidants of the ink compositions protect the images from
oxidation and also
protect the ink components from oxidation during the heating portion of the
ink preparation
process. Specific examples of suitable antioxidants include NAUGUARD series
of
antioxidants, such as NAUGUARD 445, NAUGUARD 524, NAUGUARD 76, and
NAUGUARD 512 (commercially available from Uniroyal Chemical Company, Oxford,
Conn.), the IRGANOX series of antioxidants such as IRGANOX 1010
(commercially
available from Ciba Geigy), and the like. When present, the optional
antioxidant can be
present in the ink in any desired or effective amount, such as in an amount of
from at least
about 0.01 to about 20 percent by weight of the ink, such as about 0.1 to
about 5 percent by
weight of the ink, or from about 1 to about 3 percent by weight of the ink,
although the
amount can be outside of these ranges.
[0070] The ink composition can also optionally contain a viscosity modifier.
Examples of suitable viscosity modifiers include aliphatic ketones, such as
stearone, and the
like. When present, the optional viscosity modifier can be present in the ink
in any desired or
effective amount, such as about 0.1 to about 99 percent by weight of the ink,
such as about 1
to about 30 percent by weight of the ink, or about 10 to about 15 percent by
weight of the ink,
although the amount can be outside of these ranges.
[0071] Other optional additives to the inks include clarifiers, such as UNION
CAW' X37-523-235 (commercially available from Union Camp); tackifiers, such as
CA 02677571 2009-09-03
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FORAL 85, a glycerol ester of hydrogenated abietic (rosin) acid (commercially
available
from Hercules), FORAL 105, a pentaerythritol ester of hydroabietie (rosin)
acid
(commercially available from Hercules), CELLOLYN 21, a hydroabietic (rosin)
alcohol
ester of phthalic acid (commercially available from Hercules), ARAKAWA KE-311
Resin, a
triglyceride of hydrogenated abietic (rosin) acid (commercially available from
Aralcawa
Chemical Industries, Ltd.), synthetic polytetpene resins such as NEVTAC 2300,
NEVTAC6
100, and NEVTAC 80 (commercially available from Neville Chemical Company),
WTNGTACK 86, a modified synthetic polyterperie resin (commercially available
from
Goodyear), and the like; adhesives, such as VERSAMID 757, 759, or 744
(commercially
available from Henkel), plasticizers, such as UNIPLEX 250 (commercially
available from
Uniplex), the phthalate ester plasticizers commercially available from
Monsanto under the
trade name SANTICIZER , such as dioctyl phthalate, diundecyl phthalate,
alkylbenzyl
phthalate (SANTICIZER 278), triphenyl phosphate (commercially available from
Monsanto). KP-140 , a tributoxyethyl phosphate (commercially available from
FMC
Corporation), MORFLEX 150, a dicyclohexyl phthalate (commercially available
from
Mofflex Chemical Company Inc.), trioctyl trimellitate (commercially available
from Eastman
Kodak Co.), and the like; and the like. Such additives can be included in
conventional
amounts for their usual purposes.
Surfactants
[0072] Examples of nonionic surfactants that may be used in the ink according
to
the present disclosure include, without limitation, polyvinyl alcohol,
polyacrylic acid,
methalose, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxy ethyl
cellulose,
carboxy methyl cellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl
ether,
polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether,
polyoxyethylene ley' ether,
polyoxyethylene sorbitarA monolaurate, polyoxyethylene stearyl ether,
polyoxyethylene
nonylphenyl ether, dialkylphenoxypoly(ethyleneoxy)ethanol, and the like, and
mixtures
thereof. A suitable concentration of the nonionic surfactant is, for example,
from about 0.01
to about 10 weight percent, and in embodiments in an amount of about 0.1 to
about 5 weight
percent.
[0073] Examples of suitable cationic surfactants include, without limitation,
alkylbenzyl dimethyl ammonium chloride, diallcyl benzenealkyl ammonium
chloride, lauryl
trimethyl ammonium chloride, alkylbenzyl methyl ammonium chloride, alkyl
benzyl dimethyl
ammonium bromide, benzalkonium chloride, cetyl pridinium bromide, C12, C15,
C17 -
trimethyl ammonium bromides, halide salts of quatemized
polyoxyethylallcylarnines,
CA 02677571 2009-09-03
20
dodecylbenzyl triethyl ammonium chloride, and the like, and mixtures thereof.
A suitable
amount of surfactant can be selected, such as in an amount of about 0.1 to
about 10 weight
percent, such as from about 0.2 to about 5 weight percent of the ink weight,
although the
amount can be outside of these ranges. The choice of particular surfactants or
combinations
thereof as well as the amounts of each to be used are within the purview of
those skilled in
the art.
Preparation of Ink
[00741 The ink composition of the present disclosure can be prepared by any
desired
or suitable method. For example, in the case of solid or phase change inks, or
even curable
inks, the ink ingredients can be mixed together, followed by heating,
typically to a
temperature of from about 100 C to about 140 C, although the temperature can
be outside of
this range, and stirring until a homogeneous ink composition is obtained,
followed by cooling
the ink to ambient temperature (typically from about 20 C to about 25 C). In
the case of
liquid ink compositions, the ink ingredients can simply be mixed together with
stirring to
provide a homogeneous composition, although heating can also be used if
desired or
necessary to help form the composition. Other methods for making ink
compositions are
known in the art and will be apparent based on the present disclosure.
[0075] The MICR ink according to the present disclosure may be, for example,
an
aqueous ink, an oil, ink, a curable ink, a solid ink, or a hot-melt ink.
[0076] The ink may be produced by any known method blending the above
mentioned components, melting with kneading the mixture and pulverizing the
resultant
mass. Moreover, it may be produced by a polymerization method which comprises
blending
monomers for the binder with other ingredients and polymerizing the mixture.
Printing of the Ink
[0077] The magnetic metal particle ink may generally be printed on a suitable
substrate such as, without limitation, paper, glass art paper, bond paper,
paperboard, Kraft
paper, cardboard, semi-synthetic paper or plastic sheets, such as polyester or
polyethylene
sheets, and the like. These various substrates can be provided in their
natural state, such as
uncoated paper, or they can be provided in modified forms, such as coated or
treated papers
or cardboard, printed papers or cardboard, and the like.
[00781 For printing the IVIICR ink on a substrate, any suitable printing
method may
be used. For example, suitable methods include, without limitation, roll-to-
roll high volume
analog printing methods, such as gravure, rotogravure, flexography,
lithography, etching,
CA 02677571 2012-05-14
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screenprinting, and the like. Additionally, thermography, electrophotography,
electrofgaphy,
laser induced transfer, inkjet printing, or a combination thereof may be used.
If a laser
induced transfer digital printing method is used, exemplary methods of such
method are dye
sublimination, ablation, melt transfer, or film transfer. The ink may also be
used for a
thermal transfer printer, a hot-melt printer and ordinary instrument for
writing. In a particular
embodiment, the method used is inkjet printing.
[0079] The ink of the present disclosure may be used in both MICR and non-MICR
applications.
EXAMPLES
Solid Ink Examples
Example 1 (Preparation of Carbon Black Pigment Dispersion, Extrudate A)
[0080] Triamide resin (prepared as described in Example II of U.S. Patent No.
6,860,930) was processed through a blender to form a powder. About 750.72g of
the
powderized triamide resin, and about 239.7g of Nipex 150 carbon black
(obtained from
Degussa Canada, Burlington, Ontario) were admixed in a LITTLEFORD M5 blender
for
about 30 minutes at 0.8A. The powder mixture was added at a rate of 0.8 pounds
per hour to
a DAVO counter-rotating twin screw extruder (Model VS 104, from Deutsche
Apparate-
Vertrieborganisation GmbH & Co, Troisdorf, Germany). The contents of the
extruder were
then mixed at 70 C at 50 RPM. The outlet temperature was set at 75 C. The
extruded
dispersion, Extrudate A, was melt-mixed with other ink ingredients to form
carbon black inks
as described in Examples 2 to 5.
Example 2 (Control Solid Ink with no Magnetic Particles)
[0081] Extrudate A prepared as described in Example 1 (13.13 wt % of the total
ink
weight, about 19.70g) and Petrolite CA-11 diurethane dispersant (3.95 wt % of
the total ink
weight, about 5.92g) were weighed in a first 250 milliliter beaker (A).
Kemamide S180
from Crompton Corp. (15.19 wt % of the total ink weight, 22.79g), KE100 resin
from
Arakawa Chemical Industries Ltd. (10.85 wt % of the total ink weight, about
16.28g), and
Naugard N445 from Crompton Corp. (0.12 wt % of the total ink weight, about
0.18g) were
weighed in a second 250 milliliter beaker (B). Polyethylene wax from Baker
Petrolite (54.26
wt % of the total ink weight, about 81.39g), and the urethane resin described
in Example 4 of
U.S. Patent No. 6,309,453, (2.5 wt % of the total ink weight, about 3.74g)
were weighed in a
third 250 milliliter beaker (C). Beakers A, B, and C were heated at 130 C for
approximately
three hours. After two hours of heating, the
CA 02677571 2009-09-03
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components in beaker B were stirred with a heated spatula to aid in melting
and dissolving
the mixture, and this was repeated 30 minutes later. Once the mixture in
beaker B was fully
dissolved and melted, the contents in beaker B were poured into beaker A.
[00821 Sonic Dismembrator Model 500 Sonifier was used to sonify the contents
of
beaker A for 6 intervals of 30 seconds each, thus producing a total
sonification process time
of three minutes. While sonifying, the beaker was rotated to ensure even
processing
throughout the mixture with the temperature maintained below 130 C. After the
first three
minutes of sonification, beaker A was heated at 110 C for 30 minutes. The
sonification
process was then repeated on beaker A two more times, with the contents in
beaker C being
gradually poured into beaker A throughout the first 30-second sonification
interval of the
third sonification round. The carbon black ink thus prepared exhibited a
viscosity of about
10.8 centipoise (cps) as measured on an AR2000 Rheometer from TA Instruments.
The ink
was then filtered through a 1 pm glass fiber disc filter and then a 0.45 ptrn
glass fiber disc
filter at 110 C with an applied pressure of 15 pounds per square inch (psi).
The final ink was
then cooled to room temperature and tested on a Xerox PFIA.SER 8400 piezo
ink jet
printer. The composition of this ink is shown in Table 3 below.
Example 3 (Control Solid Ink with no Magnetite Particles)
100831 A carbon black ink was prepared as described in Example 2 except that
WB-
diurethane dispersant (available from Baker Petrolite) was used in place of
Petrolite CA-11
(available from Baker Petrolite). The composition of this ink is shown in
Table 3 below.
Example 4 (Control Solid Ink with no Magnetite Particles)
100841 A carbon black ink was prepared as described in Example 2 except that
WB-
17 diurethane dispersant (available from Baker Petrolite) was used in place of
Petrolite CA-
11. The composition of this ink is shown in Table 3 below.
Example 5 (Control Solid Ink with no Magnetite Particles)
[0085] The following components wcre melted and stir-mixed in a 4 liter beaker
(A)
at 125 C: Extrudate A prepared as described in Example 1 (13.13 wt % of the
total ink
weight, about 367.64g), Petrolite CA-11 (3.94 wt % of the total ink weight,
about 110.49g),
Kemamide S180 from Crompton Corp. (15.19 wt % of the total ink weight, about
425.41g),
KE100 resin from Arakawa Chemical Industries Ltd. (10.85 wt % of the total ink
weight,
about 303.86g), and NaugareN445 from Crompton Corp. (0.12 wt % of the total
ink weight,
about 3.40g). Beaker (A) was equipped with a heating mantel and a mechanical
stirrer. The
carbon black dispersion was heated and stirred for an hour at 125 C. in a
second 4 liter
CA 02677571 2012-05-14
23
beaker (B), distilled polyethylene wax from Baker Petrolite (as described in
U.S. Patent
Publication No. 2007/0120916, the disclosure of which is entirely incorporated
herein by
reference; 54.24 wt % of the total ink weight, about 1,519.32g), and the
urethane resin
described in Example 4 of U.S. Patent No. 6,309,453, the disclosure of which
is entirely
incorporated by reference herein, (2.53 wt % of the total ink weight, about
70.80g) were melt-
mixed at 125 C. Beaker (B) was also equipped with a heating mantel and a
mechanical
stirrer. The resin dispersion in beaker (B) was heated and stirred for an hour
to ensure that all
resins were fully melt-mixed.
[0086] An IKA Ultra Turrax T50 Homogenizer was used to homogenize the
ingredients in beaker (A) for 30 minutes at 125 C. The molten resin mixture in
beaker (B),
which was kept at 125 C, was added into the homogenized pigment dispersion in
beaker (A).
The carbon black ink in beaker (A) was further homogenized for an additional
30 minutes.
The rheology of the carbon black ink in beaker (A) was measured using the
AR2000
Rheometer. The resulting carbon black ink was filtered at 115 C through a 1
rn glass fiber
cartridge-filter and then through a 0.45 p.m glass fiber cartridge-filter
under low pressure (less
than 5 psi). The ink was then cooled to room temperature. The final ink was
tested on a
Xerox'l Phaser 8860 piezo ink jet printer.
Example 6 (Preparation of Magnetic Fe Particles A)
[0087] Magnetic Fe particles are prepared according to the procedure described
by
Watari et al., J. Materials Science, 23, 1260-1264 (1988). The mineral
goethite a-Fe0OH
with 0.5 m particle size is reduced under isothermal heat treatment at 400 C
in a hydrogen
atmosphere for 2 hours to convert the particles to Fe metal particles of 20 x
20 x 200 nm in
size, with an aspect ratio of 10/1, a remnant moment of 72.2 emu/g, a
coercivity of 1540
Oersteds and a magnetocrystalline anisotropy of about 4 x 104 J/m3, as
measured by
Luborsky, J. App!. Phys, Supplement to Vol. 32 (3), 171S-184S (1961).
Example 7 (Preparation of Magnetic Fe Particles B)
[0088] Magnetic FePt particles are prepared according to the procedure
described
by Li et al., Journal of Applied Physics 99, 08E911 (2006). 15-nm FePt
nanoparticles are
chemically synthesized in an argon atmosphere. The x-ray crystal structure of
the FePt is fcc.
NaC1 powder is ball milled for 24 hours. The ball-milled NaC1 powder is then
dispersed in
hexane and mixed with hexane dispersion of the as-synthesized fcc FePt
nanoparticles, such
that the ratio of NaCl to FePt is 100:1. The mixture is stirred until all the
solvent evaporates,
and annealed in forming gas (93% H2 and 7% Ar) at 700 C for 2 hrs to convert
the FePt to the
CA 02677571 2012-05-14
24
desired fct crystal structure. The salt is washed out with water, and the
particles are dried.
The magnetic Fe particles are cubic with a size of 15 nm, an aspect ratio of
1/1, a remnant
moment of about 40 emu/g, and a coercivity of 20,000 Oersteds and a
magnetocrystalline
anisotropy of 660 x 104 J/m3.
Example 8 (Preparation of Magnetic Fe Dispersion, Extrudate B)
[0089] The steps described in Example 1 are carried out, except that 71.91g of
magnetic Fe particle A prepared as described in Example 6 is added to form
Extrudate B.
Example 9 (Preparation of Extruded Dispersion, Extrudate C)
[0090] The steps described in Example 8 are carried out, except that about
200.00g,
instead of 71.91g, of magnetic Fe particle A prepared as described in Example
6, is used.
Example 10 (Low Energy Heterogeneous Magnetic Carbon Black Pigmented Ink)
100911 Extrudate B prepared as described in Example 8 (13.13 wt % of the total
ink
weight, about 19.70g) and Petrolite CA-11 diurethane dispersant (3.95 wt % of
the total ink
weight, about 5.92g) are weighed in a first 250 milliliter beaker (A).
Kemamide S180 from
Crompton Corp. (15.19 wt % of the total ink weight, about 22.79g), KE100 resin
from
Arakawa Chemical Industries Ltd. (10.85 wt % of the total ink weight, about
16.28g), and
Naugard N445 from Crompton Corp. (0.12 wt % of the total ink weight, about
0.18g) are
weighed in a second 250 milliliter beaker (B). Polyethylene wax from Baker
Petrolite (54.26
wt % of the total ink weight, about 81.39g), and the urethane resin described
in Example 4 of
U.S. Patent No. 6,309,453, (2.5 wt % of the total ink weight, about 3.74g) are
weighed in a
third 250 milliliter beaker (C). Beakers A, B, and C are heated for
approximately three hours
at 130 C. After two hours of heating, the components in beaker B are stirred
with a heated
spatula to aid in melting and dissolving the mixture, and this is repeated 30
minutes later.
Once the mixture in beaker B is fully dissolved and melted, the contents in
beaker B are
poured into beaker A.
100921 The magnetic carbon black ink thus prepared exhibits a projected
viscosity
of about 11 cps as measured on an AR2000 rheometer from TA Instruments. This
viscosity is
estimated from the viscosity of inks containing only carbon black, which
viscosity is typically
in the range of about 10 to about 11 cps at about 110 to about 140 C. If the
Fe particles are
well dispersed, they are not expected to increase in viscosity by more than
about 10 to about
20 percent, depending on the concentration of Fe particles. The ink is then
filtered
subsequently through a 6 gm and then optionally a 1.0 pm glass fiber disc
filter at 110 C with
CA 02677571 2009-09-03
25
an applied pressure of 15 psi. The final ink is then cooled to room
temperature and printed.
The composition of this ink is shown in Table 3 below.
Example 11
[0093] The following components are melted and stir-mixed in a 4 liter beaker
(A)
at 125 C: Extrudate C prepared as described in Example 9 (13.13 wt % of the
total ink
weight, about 367.64g), Petrolite CA-11 (3.94 wt % of the total ink weight,
about 110.49g),
Kemainide S180 from Crompton Corp. (15.19 wt % of the total ink weight, about
425.41g),
KE100 resin from Arakawa Chemical Industries Ltd. (10.85 wt % of the total ink
weight,
about 303.86g), and Naugard N445 from Crompton Corp- (0A2 wt % of the total
ink weight,
about 3.40g). Beaker (A) is equipped with a heating mantel and a mechanical
stirrer. The
magnetite containing carbon black dispersion is heated and stirred for an hour
at 125 C. In a
second 4 liter beaker (B), polyethylene wax from Baker Petrolite (5424 wt % of
the total ink
weight, about 1,519.32g), and the urethane resin described in Example 4 of
U.S. Patent No.
6,309,453, incorporated by reference herein in its entirety (2.53 wt % of the
total ink weight,
about 70.80g), are melt-mixed at 125 C. Beaker (B) is also equipped with a
heating mantel
and a mechanical stirrer. The resin dispersion in beaker (B) is heated and
stirred for an hour
to ensure that all resins are tally melt-mixed.
10094] An IKA Ultra Turrax T50 Homogenizer is used to homogenize the
ingredients in beaker (A) for 30 minutes with the temperature maintained at
125 C during
homogenization. The molten resin mixture in beaker (B), which is kept at 125
C, is then
added into the homogenized pigment dispersion in beaker (A). The magnetic
carbon black
ink in beaker (A) is further homogenized for an additional 30 minutes. After
filtering the
resulting ink subsequently through a 6 am and then a 1.0 gm glass fiber
cartridge-filter at
115 C under low pressure (less than 5 psi), the ink is cooled to room
temperature. The final
ink is then printed using an ink jet printer. The composition of this ink is
shown in Table 3
below.
Examole 12
[0095] A magnetic carbon black ink is prepared as described in Example 11,
except
that an additional 200g of Extrudate C is added to the ink after the final 30
minute
homogenization step, and the ink is homogenized for an additional 20 minutes.
The
composition of this ink is shown in Table 3 below.
CA 02677571 2009-09-03
26
Example 13 (Preparation of Magnetic FePt Particle Extrudate, Extrudate D
[00961 The steps described in Example 8 are carried out, except that 71.91g of
magnetic FePt particle B of Example 7 is used instead of 71.91g of the
magnetic Fe particle A
of Example 6.
Example 14 (Low Energy Heterogeneous Magnetic Carbon Black Pigmented Ink/
[00971 Extrudate D prepared as described in Example 13 (13.13 \Ali % of the
total
ink weight, about I9.70g) and Petrolite CA-11 (3.95 wt % of the total ink
weight, about
5.92g) are weighed in a first 250 milliliter beaker (A). Kemamide S180 from
Crompton
Corp. (15.19 wt % of the total ink weight, about 22.79g), ICE100 resin from
Arakawa
Chemical Industries Ltd. (10.85 wt % of the total ink weight, about 16.28g),
and Naugard
N445 from Crompton Corp. (0.12 wt % of the total ink weight, about 0.18g) are
weighed in a
second 250 milliliter beaker (B). Polyethylene wax from Baker Petrolite (54.26
wt % of the
total ink weight, about 81.39g), and the urethane resin described in Example 4
of U.S. Patent
No. 6,309,453, herein incorporated by reference in its entirety (2.5 wt % of
the total ink
weight, about 3.74g). are weighed in a third 250 milliliter beaker (C).
Beakers A, B, and C
are heated at 115 C for approximately three hours. After two hours of heating,
the
components in beaker B are stirred with a heated spatula to aid in melting and
dissolving the
mixture, and this is repeated 30 minutes later. Once the mixture in beaker B
is fully dissolved
and melted, the contents in beaker B are poured into beaker A.
[0098] The magnetic carbon black ink thus prepared is expected to exhibit a
viscosity of about 11 cps at about 110 C to about 140 C as measured on an
AR2000
Rheometer from TA Instruments. The ink is then filtered subsequently through a
6 um and
then a 1.0 um glass fiber disc filter at 110 C with an applied pressure of 15
psi. The final ink
is then cooled to room temperature and printed using an ink jet printer. The
composition of
this ink is shown in Table 3 below.
Example 15
[00991 A magnetic carbon black ink is prepared as described in Example 12,
except
that WB-5 dispersant is used in place of Petrolite CA-11. The composition of
this ink is
shown in Table 3 below.
Example 16
[0100] A magnetic carbon black ink is prepared as described in Example 12,
except
that WB-17 dispersant is used in place of Petrolite CA-11. The composition of
this ink is
shown in Table 3 below.
CA 02677571 2009-09-03
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Example 17 (Preparation of Magnetic FePt Dispersion, Extrudate El
[0101] The steps described in Example 8 are =Tied out, except that about
200.00g
of magnetic FePt particle B prepared as described in Example 7 is used instead
of 71.91g of
the magnetic Fe particle A prepared as described in Example 6.
Example 18
10102] A carbon black ink is prepared as described in Example 12 using
Extrudate
E prepared as described in Example 17 (instead of Extmdate C prepared as
described in
Example 9). The composition of this ink is shown in Table 3 below.
Example 19
101031 A carbon black ink is prepared as described in Example 14, except that
WB-
dispersant is used in place of Petrolite CA-11. The composition of this ink is
shown in
Table 3 below,
Example 20
[01041 A carbon black ink is prepared as described in Example 14, except that
WB-
17 dispersant is used in place of Petrolite CA-11. The composition of this ink
is shown in
Table 3 below.
Aqueous Ink
Example 21 (Aqueous Car i on Black Ink Containiu Magnetic FePt P rticle B
101051 39.9g of the magnetic FePt particles prepared as described in Example 7
are
added to 300g of deionized water containing 1.3g of 20% aqueous anionic
surfactant Dowfax
2AlTm, to which 83g of 18% Nipee 150 carbon black (obtained from Degussa
Canada,
Burlington, Ontario) solution are added and ball milled for 3 hours to produce
the pigment
dispersion.
[0106] An aqueous ink composition is prepared by adding while mixing 15.25g of
diethyleneglycol, 5.0g ofJeffamine ED-600, polyether diamines (available from
Texaco
Chemical Co.), and 20.15g of the prepared pigment dispersion to 59.6g of
deionized water.
This ink may be printable using either a thermal or piezoelectric inkjet
printer.
CA 02677571 2009-09-03
28
Table 3
.... ,
Control Inks Ink Compositions
-
Components (weight 2 3 4 5 10 11
12 14 15 16 18 ' 19 20
% of total ink weigh9
Triamide Resin 9.95 10.3 10.26 9.95 9.28 8.28
11.92 9.28 9.28 9.28 11.92 , 9.28 .õ 9.28
Nipcx" 150 Carbon 3.18 3,06 3.05 3.18 ' 2.96 2.64
3_81 2.96 2.96 2.96 3.81 2.96 2.96
Black I
Urethane Derivative 3.95 0 0 3.94 3.95 3.94
3.68 3.95 0 0 3.68 0 0
-Petrolite CA-11rm
Urethane Derivative 0 2.64 0 0 0 0
0 -0 2.87 0 0 2.87 0
wg..5-rm
Urethane Derivative 0 0 2.63 0 0 0
0 0 0 2.82 0 0 /82
WBl7TM
,
-KemamideTM 5180 15.19 15.25 15.4 , 15.19 15.19 15.19
14.18 15.19 15.25 15.4 14.18 15.25 15.4
1 KE100Tm Resin 10.85 10.89 11 10.85-1 10.85 10.85
10.13 10.85 10-89 11 10.13 10.89 11
_NaugareN445 , 0.12 0.12 , 0.13 0.12 0.12 0_12 0.11
0.12 0.12 0.12 0.11 0.12 0.12
Po1 ell lenc Wax 54.26 55_2 55 54.24 54.26 54.24 50.63
54.26 55.2 55 50.63 55.2 55
Urethane Resin 2.5 .., 2.54 , 2.53 2.53 15 2.53
2.36 2.5 2.54 2.53 136 2.54 _ 2,53
Magnetite Pigment A 0 , 0 ii 0- 0,89 2.21
3.18 ' 0 0.89 0.89 0 0 0
Magnetite Pigment B
0_19 3.18 -0.89 - 0.89
Total 100 100 - 100 _ 100 100 100
100 100 100 100 100 100 _ 100 /
Viscosity, cPs, After 10.76 10.45 10.66 11.1
Filtration @ i 10 C Not tested, but
expected to be about 10.5 to 14 at about 110 C TO about 140
C
_
CA 02677571 2009-09-03
29
Example 22 (Carbon Black Concentrate Containing Mapietic Fe Particle dispersed
in
Dibutyl Sebacate)
101071 A stable magnetic carbon black concentrate in dibutyl sebacate
(available
from Morilex Inc. NC) is obtained as follows: In a 1 liter, stainless steel
beaker attached to a
DISPERMAT FT (available from VNIA-Getzmann GMBH) equipped with a 40 mm high-
shear mixing dissolver set between an initial speed of 1500 RPM and a final
speed of 2500
RPM, 60_0g of Nipexe 150G carbon black (available from Cabot) is added slowly
with high-
shear mixing to a solution of 100g of SOLSPERSE 13940 (40% active, available
from
Avecia), in 100.18g of dibutyl sebacate (available from Morflex Inc.). 40g of
magnetic Fe
particle A prepared as described in Example 6 is added The dispersion is
continuously
stirred for 2 hours after the addition of the carbon black and magnetic
particles. The loading
of dispersant to pigment is estimated at about 2.6 mg/m2, providing optimum
conditions for
stability.
[01081 This dispersion is further processed for 270 minutes in a DISPERMAT SL-
C
12 (available from VMA.-Getzmann GMBH), under the following conditions: speed
= 2000
RPM; temperature = 30-55 C (water cooled); circulation rate ¨ 3g/s through a
125 ml
chamber; amount of milling beads = 100 ml; type of beads = 0.8-1.0 zirconium-
silicon
dioxide.
Example 23 (Preparation of Cobalt Salt of Linolenic Acid)
[01091 The Cobalt Salt of Linolenic Acid may be produced as described in
Example
of U.S. Patent Application Publication No. 2007/0120923A1.
[0110] The cobalt salt of linolenic acid may be obtained by direct
electrochemical
synthesis, as described by Kumar, N. et al., Canadian Journal of Chemistry
(1987), 65(4),
740-3. Specifically, 0.1g of linolenic acid is dissolved in 50 ml. acetone
containing 0.04g of
Et2NC104. This solution is added to prepare simple electrochemical cells in
the form
Pt"/CH3CN-F-linolenic acid/Co('' and an initial voltage of 25V is applied for
45 minutes.
The cobalt (II) linolenic acid salt precipitates directly during
electrochemical oxidation.
10111] Alternatively, the cobalt salt of linolenic acid may be prepared by a
precipitation process, such as by adding water-soluble cobalt sulphate to a
hot sodium salt
solution of the linolenic acid with agitation until precipitation is complete.
The resulting salt
is washed and dried by conventional methods. Cobalt salts of linolic acids may
be similarly
obtained by these methods.
CA 02677571 2009-09-03
30
Examtles 24-27 alvdr4sHbon Based Carbon Black Ink Compositions Containing
Magnetic Fe Particles)
[01121 Ink compositions 24-27 containing magnetic particles are prepared by
dispersing, with a high shear mixer, the stable magnetic carbon black
concentrate prepared as
described in Example 22 into a vehicle, a blend of linear and branched alcanes
with an
alcohol, and then adding a metal salt. Table 4 sets forth the specific
compositions of
Examples 24-27. Optionally, the metal salt may be manganese stearate.
Table 4
Example Vehicle
Metal Salt Colorant
Linear Alkane Branched Alkane Alcohol
Type Wreµ Type Wt% Type Wt% Type Wt% Type Wt%
of the of the of the of the
of the
Total Total Total Total
Total
Ink Ink Ink Ink
Ink
Weight Weight Weight Weight
Weight
¨ ¨ ¨
24 n- 20 ISOPAR V 47 Olcyl 20
ADDITOL 3 Example 10
hexadecanc (EXXON) Alcohol VXW
22
(Aldrich) (Sigma 6206
Aldrich) (Solutia
Inc.)
2$ NORPAR 1 27.5 ISOPAR V 39.5 Olcyl 20
ADDITOL 3 Example 12
5 (EXXON) Alcohol VXW
22
(EXXON) (Sigma 6206
Aldrich) (Solutia
_ . Inc.)
.
26 NORPAR 1 7 ISOPAR L 56 Oleyl 25
Cobalt salt 2 Example 5
5 (EXXON) Alcohol of linolic
22
(EXXON) (Sigma acid
Aldrich) (Example
23) ¨
27 n- 12 SHELLS01.. T 52 Olcyl 24
Cobalt salt 2 Example 7
hexadecanc (Shell) Alcohol of
linolic 22
(Aldrich) (Sigma acid
Aldrich) (Example
23) t
[0113] It will be appreciated that various of the above-disclosed and other
features
and functions, or alternatives thereof, may be desirably combined into many
other different
systems or applications- Also, various presently unforeseen or unanticipated
alternatives,
modifications, variations or improvements therein may be subsequently made by
those skilled
in the art, and are also intended to be encompassed by the following claims,
