Note: Descriptions are shown in the official language in which they were submitted.
CA 02813472 2013-04-19
4
RAPID SOLIDIFYING CRYSTALLINE-AMORPHOUS INKS
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001]
Reference is made to commonly owned and co-pending, U.S.
Patent Application Serial No. ____________________________________________
(not yet assigned) entitled
"Phase Change Ink Compositions Comprising Crystalline Diurethanes And
Derivatives Thereof" to Naveen Chopra et al., electronically filed on the same
day herewith (Attorney Docket No. 20110356-396152); U.S. Patent
Application Serial No. _____________________________________________________
(not yet assigned) entitled "Phase
Change Ink Compositions Comprising Crystalline Sulfone Compounds and
Derivatives Thereof" to Kentaro Morimitsu et al., electronically filed on the
same day herewith (Attorney Docket No. 20110561-396955); U.S. Patent
Application Serial No. _____________________________________________________
(not yet assigned) entitled "Phase
Change Inks Comprising Crystalline Amides" to Kentaro Morimitsu et al.,
electronically filed on the same day herewith (Attorney Docket No. 20110665-
397243); U.S. Patent Application Serial No. ______________________ (not yet
assigned) entitled "Phase Change Ink Compositions Comprising Aromatic
Ethers" to Kentaro Morimitsu et al., electronically filed on the same day
herewith (Attorney Docket No. 20110362-396157); U.S. Patent Application
Serial No. _______________________________________________________________
(not yet assigned) entitled "Fast Crystallizing
Crystalline-Amorphous Ink Compositions And Methods For Making The
Same" to Gabriel Mime et al., electronically filed on the same day herewith
(Attorney Docket No. 20110459-399389);U.S. Patent Application Serial No.
_________________________ (not yet assigned) entitled "Phase Change Inks
Comprising
Inorganic Nucleating Agents" to Daryl W. Vanbesien et al., electronically
filed
on the same day herewith (Attorney Docket No. 20111206-400896); U.S.
Patent Application Serial No. ____________________________________________
(not yet assigned) entitled
"Phase Change Inks Comprising Fatty Acids" to Gabriel Mime et al.,
electronically filed on the same day herewith (Attorney Docket No. 20110815-
399390); U.S. Patent Application Serial No. _____________________ (not yet
assigned) entitled "Phase Change Inks Comprising Aromatic Diester
Crystalline Compounds" to Kentaro Morimitsu et al., electronically filed on
the
same day herewith (Attorney Docket No. 20111040-399927); U.S. Patent
Application Serial No. _____________________________________________________
(not yet assigned) entitled "Phase
CA 02813472 2013-04-19
. ,
Change Ink Compositions Comprising Diurethanes as Amorphous Materials"
to Naveen Chopra et al., electronically filed on the same day herewith
(Attorney Docket No. 20110610-397242); U.S. Patent Application Serial No.
_________________________ (not yet assigned) entitled "Phase Change Inks
Comprising
Organic Pigments" to Jennifer Belelie et al., electronically filed on the same
day herewith (Attorney Docket No. 20110418-399388); and U.S. Patent
Application Serial No. ______________________ (not yet assigned) entitled
"TROM
Process for Measuring the Rate of Crystallization of Phase Change Inks" to
Gabriel Mime et al., electronically filed on the same day herewith (Attorney
Docket No. 20110828-401275), U.S. Patent Application Serial No.
_________________________ (not yet assigned) entitled "Rapidly Crystallizing
Phase
Change Inks and Methods for Forming the Same" to Jennifer Belelie et al.,
electronically filed on the same day herewith (Attorney Docket No. 20111455-
403044); the entire disclosures of which are incorporated herein by reference
in its entirety.
BACKGROUND
[0002] The present embodiments relate to phase change ink
compositions characterized by being solid at room temperature (e.g., 20-27
C) and molten at an elevated temperature at which the molten ink is applied
to a substrate. These phase change ink compositions can be used for ink jet
printing. The present embodiments are directed to a novel phase change ink
composition comprising an amorphous material, a crystalline material, and
optionally a colorant, and methods of making the same.
[0003] Ink jet printing processes may employ inks that are
solid at room
temperature and liquid at elevated temperatures. Such inks may be referred
to as solid inks, hot melt inks, phase change inks and the like. For example,
U.S. Pat. No. 4,490,731, the disclosure of which is totally incorporated
herein
by reference, discloses an apparatus for dispensing phase change ink for
printing on a recording medium such as paper. In piezo ink jet printing
processes employing hot melt inks, the phase change ink is melted by the
heater in the printing apparatus and utilized (jetted) as a liquid in a manner
similar to that of conventional piezo ink jet printing. Upon contact with the
printing recording medium, the molten ink solidifies rapidly, enabling the
colorant to substantially remain on the surface of the recording medium
2
CA 02813472 2013-04-19
instead of being carried into the recording medium (for example, paper) by
capillary action, thereby enabling higher print density than is generally
obtained with liquid inks. Advantages of a phase change ink in ink jet
printing
are thus elimination of potential spillage of the ink during handling, a wide
range of print density and quality, minimal paper cockle or distortion, and
enablement of indefinite periods of nonprinting without the danger of nozzle
clogging, even without capping the nozzles.
[0004] In general, phase change inks (sometimes referred to as "hot
melt inks") are in the solid phase at ambient temperature, but exist in the
liquid phase at the elevated operating temperature of an ink jet printing
device. At the jetting temperature, droplets of liquid ink are ejected from
the
printing device and, when the ink droplets contact the surface of the
recording
medium, either directly or via an intermediate heated transfer belt or drum,
they quickly solidify to form a predetermined pattern of solidified ink drops.
[0005] Phase change inks for color printing typically comprise a phase
change ink carrier composition which is combined with a phase change ink
compatible colorant. In a specific embodiment, a series of colored phase
change inks can be formed by combining ink carrier compositions with
compatible subtractive primary colorants. The subtractive primary colored
phase change inks can comprise four component dyes or pigments, namely,
cyan, magenta, yellow and black, although the inks are not limited to these
four colors. These subtractive primary colored inks can be formed by using a
single dye or pigment or a mixture of dyes or pigments. For example,
magenta can be obtained by using a mixture of Solvent Red Dyes or a
composite black can be obtained by mixing several dyes. U.S. Pat. No.
4,889,560, U.S. Pat. No. 4,889,761, and U.S. Pat. No. 5,372,852, the
disclosures of each of which are totally incorporated herein by reference,
teach that the subtractive primary colorants employed can comprise dyes
from the classes of Color Index (C.I.) Solvent Dyes, Disperse Dyes, modified
Acid and Direct Dyes, and Basic Dyes. The colorants can also include
pigments, as disclosed in, for example, U.S. Pat. No. 5,221,335, the
disclosure of which is totally incorporated herein by reference. U.S. Pat. No.
5,621,022, the disclosure of which is totally incorporated herein by
reference,
3
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. .
discloses the use of a specific class of polymeric dyes in phase change ink
compositions.
[0006] Phase change inks are desirable for ink jet printers
because
they remain in a solid phase at room temperature during shipping, long term
storage, and the like. In addition, the problems associated with nozzle
clogging as a result of ink evaporation with liquid ink jet inks are largely
eliminated, thereby improving the reliability of the ink jet printing.
Further, in
phase change ink jet printers wherein the ink droplets are applied directly
onto
the final recording medium (for example, paper, transparency material, and
the like), the droplets solidify immediately upon contact with the recording
medium, so that migration of ink along the printing medium is prevented and
dot quality is improved.
[0007] While the above conventional phase change ink technology
is
successful in producing vivid images and providing economy of jet use and
substrate latitude on porous papers, such technology has not been
satisfactory for coated substrates. Thus, while known compositions and
processes are suitable for their intended purposes, a need remains for
additional means for forming images or printing on coated paper substrates.
As such, there is a need to find alternative compositions for phase change ink
compositions and future printing technologies to provide customers with
excellent image quality on all substrates, including selecting and identifying
different classes of materials that are suitable for use as desirable ink
components. There is a further need for printing these inks at high speeds as
required by digital presses in production environment.
[0008] Each of the foregoing U.S. patents and patent
publications are
incorporated by reference herein. Further, the appropriate components and
process aspects of the each of the foregoing U.S. patents and patent
publications may be selected for the present disclosure in embodiments
thereof.
[0009] There is further a need to provide such phase change ink
compositions which are suitable for fast printing environments like production
printing.
SUMMARY
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. .
[0010] According to embodiments illustrated herein, there is
provided
novel phase change ink compositions comprising an amorphous and, a
crystalline material which are suitable for ink jet high speed printing,
including
printing on coated paper substrates. In particular, these phase change ink are
capable of crystallizing at a total crystallization time of less than 15
seconds.
[0011] In particular, the present embodiments provide a phase change
ink comprising an amorphous compound; and a crystalline compound;
wherein the phase change ink is capable of crystallizing at a
total crystallization time of less than 15 seconds.
[0012] In embodiments, there is provided a phase change ink
comprising an amorphous compound; and a crystalline compound; a
crystallization accelerating additive; wherein the phase change ink is capable
of crystallizing at a total crystallization time of less than 15 seconds.
[0013] In further embodiments, there is provided a phase change
ink
comprising an amorphous compound; and a crystalline compound; wherein
the phase change ink is capable of crystallizing at a total crystallization
time of
less than 15 seconds; wherein the amorphous compound comprises an
amorphous core moiety having at least one functional group and being
attached to at least one amorphous terminal group; the crystalline compound
comprises a crystalline core moiety having at least one functional group and
being attached to at least one crystalline terminal group; wherein no one
functional group in the amorphous core moiety is the same as any of the
functional group of the crystalline core moiety and wherein the amorphous
terminal group comprises an alkyl, wherein the alkyl is straight, branched or
cyclic, saturated or unsaturated, substituted or unsubstituted, having from
about 1 to about 16 carbon atoms; and wherein the crystalline terminal group
comprises an aromatic groups.
[0014] In yet other embodiments, there is provided a phase
change ink
comprising an amorphous comprises an ester of tartaric acid of Formula I or
an ester of citric acid of Formula II
OHO
RiOrc),R2
0 OH
Formula I
CA 02813472 2013-04-19
R5
0 6
o .-,-- 0
R3,0 o' R4
OH
Formula II
wherein each R1, R2, R3, R4 and R5 is independently an alkyl group, wherein
the alkyl can be straight, branched or cyclic, saturated or unsaturated,
substituted or unsubstituted, having from about 1 to about 16 carbon atoms; a
crystalline compound; and a colorant; wherein the phase change ink is
capable of crystallizing at a total crystallization time of less than 15
seconds;
wherein the crystalline/amorphous ratio is from about 60:40 to about 95:5.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] For a better understanding of the present embodiments,
reference may be had to the accompanying figures.
[0016] Figure 1 illustrates the TROM process showing images of
crystalline formation from crystallization onset to crystallization completion
according to an embodiment of the disclosure.
DETAILED DESCRIPTION
[0017] In the following description, it is understood that other
embodiments may be utilized and structural and operational changes may be
made without departure from the scope of the present embodiments disclosed
herein.
[0018] Phase change ink technology broadens printing capability and
customer base across many markets, and the diversity of printing applications
will be facilitated by effective integration of printhead technology, print
process
and ink materials. The phase change ink compositions are characterized by
being solid at room temperature and molten at an elevated temperature at
which the molten ink is applied to a substrate. As discussed above, while
current ink options are successful for porous paper substrates, these options
are not always satisfactory for coated paper substrates.
[0019] It was previously discovered that using a mixture of crystalline
and amorphous small molecule compounds in phase change ink formulations
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. .
provides robust inks, and in particular, phase change inks which demonstrate
robust images on coated paper. (U.S. Patent Application Serial No.
13/095636 entitled "Solid Ink Compositions Comprising Crystalline-
Amorphous Mixtures" to Jennifer L. Belelie et. al., (Attorney Docket No.
20101286-390681) filed April 27, 2011).
[0020] Print samples made with such phase change inks
demonstrate
better robustness with respect to scratch, fold, and fold offset as compared
to
currently available phase change inks.
[0021] Such robust inks may be used with printing equipment at
high
speeds. Typically, production digital presses print at a speed comprised from
about 100 to 500 or more feet/minute. This requires inks which are capable of
solidifying very fast once placed onto the paper, in order to prevent offset
of
the printed image during fast printing process, where printed paper is either
stacked (cut-sheet printers) or rolled (continuous feed printers).
[0022] However, the present inventors discovered that in many
cases
mixtures made of crystalline and amorphous materials with optional dye
colorant solidify slowly when printed on substrates from a molten state. Such
slow solidifying inks are not suitable for high speed printing environments,
like
for example production printing, where printing at a speeds higher than 100
feet per minute is required. Solidification of the ink is due to
crystallization of
the crystalline component ink the ink when cooling.
[0023] The inventors have found that fast crystallization of a
composition made of a crystalline and an amorphous component is not an
inherent property of the composition.
[0024] In some cases, the crystallization process of a
crystalline-
amorphous ink is accelerated by careful selection of the pair of crystalline
and
amorphous component. For example a given crystalline component may be
providing a fast crystallizing composition when mixed with one amorphous
component but the same crystalline component can result in a slow
crystallizing composition when mixed with a different amorphous component.
[0025] In other cases, a given crystalline-amorphous ink
composition
can be made to crystallize faster by adding suitable crystallization
accelerators. As described before, fast crystallizing crystalline-amorphous
ink
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CA 02813472 2013-04-19
. ,
compositions are not obvious and methods for providing fast crystallizing
crystalline-amorphous inks are not disclosed in prior art.
[0026] In order to evaluate the suitability of a test ink for
fast printing a
quantitative method for measuring the rates of crystallization of phase change
inks containing crystalline components was developed. TROM (Time-
Resolved Optical Microscopy) enables comparison between various test
samples and, as a result, is a useful tool for monitoring the progress made
with respect to the design of fast crystallizing inks. TROM is described in co-
pending U.S. Patent Application Serial No. ______________________ (not yet
assigned) entitled "TROM Process for Measuring the Rate of Crystallization of
Solid Inks" to Gabriel Iftime et al., electronically filed on the same day
herewith (Attorney Docket No. 20110828-401275).
[0027] Time Resolved Optical Microscopy TROM monitors the
appearance and the growth of crystals by using Polarized Optical Microscopy
(POM). The sample is placed between crossed polarizers of the microscope.
Crystalline materials are visible because they are birefringent. Amorphous
materials or liquids, similar to, for example, inks in their molten state that
do
not transmit light, appear black under POM. Thus, POM enables an image
contrast when viewing crystalline components and allows for pursuing
crystallization kinetics of crystalline-amorphous inks when cooled from the
molten state to a set-temperature.
[0028] In order to obtain data that allow comparison between
different
and various samples, standardized TROM experimental conditions were set,
with the goal of including as many parameters relevant to the actual printing
process.
[0029] The key set parameters include:
(a) glass slides of a 16-25 mm diameter and a thickness
comprise in between 0.2 mm to 0.5 mm.
(b) ink sample thickness comprised in a range from 5 to 25
microns
(c) cooling temperature set at 40 C.
[0030] For rate of crystallization measurement, the sample is
heated to
the expected jetting temperature (viscosity = 10-12 cps) via an offline
hotplate
and then transferred to a cooling stage coupled with an optical microscope.
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. .
The cooling stage is thermostated at a preset temperature which is
maintained by controlled supply of heat and liquid nitrogen. This experimental
set-up models the expected drum/paper temperature onto which a drop of ink
would be jetted in real printing process (40 C for the experiments reported in
this disclosure). Crystal formation and growth is recorded with a camera.
[0031] The key steps in the TROM process are illustrated in
Figure 1,
highlighting the key steps in the measuring process with the mainline ink base
which contains just amorphous and crystalline components (no dye or
pigment). When viewed under POM, the molten and at time zero, the
crystalline-amorphous inks appear black as no light is passed through. As the
sample crystallizes, the crystalline areas appear brighter. The numbers
reported by TROM include: the time from the first crystal (crystallization
onset)
to the last (crystallization completion).
[0032] The definition of key measured parameters of the TROM
process are set forth below:
Time zero (1=0 s) ¨ the molten sample is placed on the cooling stage
under microscope
T onset = the time when the first crystal appears
T growth = the duration of the crystal growth from the first crystal (T
onset) to the completion of the crystallization (T total)
T total= T onset + T growth
[0033] It should be understood that the crystallization times
obtained
with the TROM method for selected inks are not identical to what would be the
crystallization times of a droplet of ink in an actual printing device. In an
actual printing device such as a printer, the ink solidifies much faster. We
determined that there is a good correlation between the total crystallization
time as measured by the TROM method and the solidification time of an ink in
a printer. In the standardized conditions described above, we determined that
inks solidify within 10-15 seconds or less measured by the TROM method, are
suitable for fast printing, typically at speeds from 100 feet/minute or
higher.
Therefore, for the purpose of the present disclosure, a rate of
crystallization
lower than 15 seconds is considered to be fast crystallizing.
[0034] In certain fast crystallizing crystalline-amorphous inks
are
provided by using a composition wherein the crystalline and amorphous
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CA 02813472 2013-04-19
components have limited compatibility. By limited compatibility it is
understood that the two components have a tendency to quickly phase
separate when cooled down from a molten state. Limited compatibility is
achieved by selecting the crystalline and amorphous components such as to
satisfy a set of design rules regarding the relationship between the
functional
groups present in the chemical structures of a selected pair of a crystalline
and amorphous components respectively, to enable the ability to fast
crystallize. (U.S. Patent Application Serial No. _______ (not yet
assigned) entitled "Fast Crystallizing Crystalline-Amorphous Ink Compositions
and Methods for Making the Same" to Gabriel Iftime et al., electronically
filed
on the same day herewith (Attorney Docket No. 20110459-399389);) The
design rules are set forth below:
(1) The phase change ink composition comprises an amorphous
compound and a crystalline compound;
(2) The amorphous compound comprises an amorphous core
moiety having at least one functional group and being attached to at least one
amorphous terminal group, wherein the amorphous terminal group comprises
an alkyl group, wherein the alkyl is straight, branched or cyclic, saturated
or
unsaturated, substituted or unsubstituted, having from about 1 to about 16
carbon atoms; a diagram showing the structure of an amorphous compound is
shown below:
-
AMORPHOUS ____________ AMORPHOUS
CORE TERMINAL
GROUP
N ___________ = \ ____________ 4
- -n
Amorphous Compound
n= 1-4
'
,
(3) The crystalline compound comprises a crystalline core
moiety having at least one functional group and being attached to at least one
crystalline terminal group, wherein the crystalline terminal group comprises
an
aromatic group; a diagram showing the structure of a crystalline compound is
shown below:
CA 02813472 2013-04-19
CRYSTALLINE CRYSTALLINE
CORE TERMINAL
GROUP
-n
Crystalline Compound
n = 1- 4
; and
(4) No one functional group in the amorphous core moiety is the
same as any of the functional group of the crystalline core moiety.
[0035] THE AMORPHOUS COMPOUND
[0036] In embodiments, the amorphous compound may comprise an
ester of tartaric acid of Formula 1 or an ester of citric acid of Formula II
OH 0
R
02
R1
0 OH
Formula 1
R5
0,6
0 0
R30)0' R4
OH
Formula 11
wherein each R1, R2, R3, R4, and R5 is independently an alkyl group, wherein
the alkyl can be straight, branched or cyclic, saturated or unsaturated,
substituted or unsubstituted, having from about 1 to about 16 carbon atoms.
In certain embodiments, each R1, R2 R3, R4 and R5 is independently a
cyclohexyl group optionally substituted with one or more alkyl groups. In
certain of such embodiments, the alkyl groups is selected from methyl, ethyl,
n-propyl, isopropyl, n-butyl and t-butyl. In certain embodiments, each R1, R2,
R3, R4 and R5 is independently a cyclohexyl group optionally substituted with
one or more alkyl groups selected from methyl, ethyl, n-propyl, isopropyl, n-
butyl and t-butyl.
[0037] Referring to Formula I, in certain embodiments, one of R1 and
R2 is 2-isopropyl-5-methylcyclohexyl, and the other one of R1 and R2 is 2-
isopropy1-5-methylcyclohexyl, 4-t-butylcyclohexyl, or cyclohexyl, or one of R1
11
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. .
and R2 is 4-t-butylcyclohexyl, and the other one of R1 and R2 is cyclohexyl.
In
certain embodiments, R1 and R2 are each 2-isopropyl-5-methylcyclohexyl. In
certain embodiments, R1 is 2-isopropy1-5-methylcyclohexyl and R2 is 4-t-
butylcyclohexyl. In certain embodiments, R1 is 2-isopropyl-5-methylcyclohexyl
and R2 is cyclohexyl. In certain embodiments, R1 is 4-t-butylcyclohexyl and
R2 is cyclohexyl.
[0038] Referring to Formula II, in certain embodiments, one
of R3,R4
and R5 is 2-isopropyl-5-methylcyclohexyl, and the other one of R3 ,R4 and R5
is 2-isopropyl-5-methylcyclohexyl, 4-t-butylcyclohexyl, or cyclohexyl, or one
of
R3,R4 and R5 is 4-t-butylcyclohexyl, and the other one of R3 ,R4 and R5 is
cyclohexyl. In certain embodiment, R3,R4 and R5 are each 2-isopropy1-5-
methylcyclohexyl. In certain embodiment, R3 is 2-isopropy1-5-
methylcyclohexyl and R4 and R5 are each 4-t-butylcyclohexyl. In certain
embodiment, R3 is 2-isopropyl-5-methylcyclohexyl and R4 and R5 are each
cyclohexyl. In certain embodiment, R1 is 4-t-butylcyclohexyl and R4 and R5
are each cyclohexyl
[0039] Some suitable amorphous materials are disclosed in U.S.
Patent
Application Ser. No. 13/095,784 to Morimitsu et at., which is hereby
incorporated by reference in its entirety. The amorphous materials may
comprise an ester of tartaric acid having a formula of
OHO
, 29 R2 Cr
FRi
0 OH
wherein R1 and R2 each, independently of the other or meaning that they can
be the same or different, is selected from the group consisting of alkyl
group,
wherein the alkyl portion can be straight, branched or cyclic, saturated or
unsaturated, substituted or unsubstituted, having from about 1 to about 16
carbon atoms. In certain embodiments, each R1 and R2 is independently a
cyclohexyl group optionally substituted with one or more alkyl group(s)
selected from methyl, ethyl, n-propyl, isopropyl, n-butyl and t-butyl.
[00401 The tartaric acid backbone is selected from L-(+)-
tartaric acid, D-
(-)-tartaric acid, DL-tartaric acid, or mesotartaric acid, and mixtures
thereof.
Depending on the R groups and the stereochemistries of tartaric acid, the
esters could form crystals or stable amorphous compounds. In specific
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CA 02813472 2013-04-19
. ,
embodiments, the amorphous compound is selected from the group
consisting of di-L-menthyl L-tartrate, di-DL-menthyl L-tartrate (DMT), di-L-
menthyl DL-tartrate, di-DL-menthyl DL-tartrate, and any stereoisomers and
mixtures thereof.
[0041] Mixtures of aliphatic alcohols may be used in the
esterification.
For example, a mixture of two aliphatic alcohols may be used in the
esterification. Suitable examples of aliphatic alcohols that can be used in
these mixed reactions are cyclohexanol and substituted cyclohexanols (e.g.,
2-, 3- or 4- -t-butyl cyclohexanol). The molar ratios of the aliphatic
alcohols
may be from 25:75 to 75:25, from 40:60 to 60:40, or about 50:50.
[0042] The amorphous compound may comprise an ester of citric
acid
disclosed in U.S. Patent Application Ser. No. 13/095,795 to Morimitsu et al.,
which is hereby incorporated by reference in its entirety. These amorphous
materials are synthesized by an esterification reaction of citric acid. In
particular, citric acid was reacted with a variety of alcohols to make tri-
esters
according to the synthesis scheme shown in U.S. Patent Application Ser. No.
13/095,795. The amorphous compounds are synthesized by an esterification
reaction of tartaric acid.
[0043] These materials show relatively low viscosity (< 102
centipoise
(cps), or from about 1 to about 100 cps, or from about 5 to about 95 cps) near
the jetting temperature (5_ 140 C, or from about 100 to about 140 C, or from
about 105 to about 140 C) but very high viscosity (> 105 cps) at room
temperature. These characteristics make the materials good candidates for
the amorphous component.
[0044] In particular, di-DL-menthyl L-tartrate (DMT) was found
to be
especially suitable for use as an amorphous compound in the present ink
embodiments.
[0045] To synthesize the amorphous component, tartaric acid was
reacted with a variety of alcohols to make di-esters as shown in the synthesis
scheme shown in U.S. Patent Application Ser. No. 13/095,784. A variety of
alcohols may be used in the esterification such as, for example, menthol,
isomenthol, neomenthol, isoneomenthol, and any stereoisomers and mixtures
thereof. Mixtures of aliphatic alcohols may be used in the esterification. For
example, a mixture of two aliphatic alcohols may be used in the
esterification.
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. .
The molar ratios of the aliphatic alcohols may be from 25:75 to 75:25, from
40:60 to 60:40, or about 50:50. Examples of suitable aliphatic alcohol whose
mixtures form amorphous compounds when reacted with tartaric acid include
cyclohexanol and substituted cyclohexanol (e.g., 2-, 3-, or 4- tert-butyl-
cyclohexanol). In embodiments, two or more molar equivalents of alcohol
may be used in the reaction to produce the di-esters of tartaric acid. If one
molar equivalent of alcohol is used, the result is mostly mono-esters.
[0046] Other suitable amorphous components include those
disclosed
in U.S. Patent Application Ser. No. 13/095,795 to Morimitsu et al., which is
hereby incorporated by reference in its entirety. The amorphous materials
may comprise a compound having the following structure:
R5
0 0O 0
R3,0 or R4
OH
R3, R4 and R5 are independently an alkyl group, wherein the alkyl can be
straight, branched or cyclic, saturated or unsaturated, substituted or
unsubstituted, having from about 1 to about 16 carbon atoms, and mixtures
thereof. In particular, tri-DL-menthyl citrate (TMC) is a desirable amorphous
candidate which affords suitable thermal and rheological properties as well
imparts robustness to the print images.
[0047] These amorphous materials are synthesized by an
esterification
reaction of citric acid. In particular, citric acid was reacted with a variety
of
alcohols to make tri-esters according to the synthesis scheme disclosed
therein. In embodiments, the phase change ink composition is obtained by
using amorphous compounds synthesized from citric acid and at least one
alcohol in an esterification reaction.
[0048] In embodiments, the amorphous compounds are formulated
with
a crystalline compound to form a solid ink composition. The ink compositions
show good rheological profiles. Print samples created by the solid ink
composition on coated paper by K-proof exhibit excellent robustness.
Furthermore, using tartaric acid as an ester base has additional advantages of
being low cost, and being obtained from a potential bio-derived source.
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CA 02813472 2013-04-19
[0049] In embodiments, the solid ink composition is obtained by using
novel amorphous compounds synthesized from tartaric acid and at least one
alcohol in an esterification reaction. The solid ink composition comprises the
amorphous compound in combination with a crystalline compound and a
colorant. The present embodiments comprise a balance of amorphous and
crystalline compounds to realize a sharp phase transition from liquid to solid
and facilitate hard and robust printed images, while maintaining a desired
level of viscosity. Prints made with this ink demonstrated advantages over
commercially available inks, such as for example, better robustness against
scratch. Thus, the present esters of tartaric acid, which provide amorphous
compounds for the solid inks, have been discovered to produce robust inks
having desirable rheological profiles and that meet the many requirements for
inkjet printing.
[0050] In embodiments, the amorphous material is present an amount
of from about 5 percent to about 40 percent by weight, or from about 5
percent to about 35 percent by weight, or from about 10 percent to about 30
percent by weight of the total weight of the ink composition.
[0051] The crystalline materials show sharp crystallization, relatively
low viscosity (5. 12centipoise (cps), or from about 0.5 to about 20 cps, or
from
about 1 to about 15 cps) at a temperature of about 140 C, but very high
viscosity (> 106 cps) at room temperature. These materials have a melting
temperature (Tmeit) of less than 150 C, or from about 65 to about 150 C, or
from about 66 to about 145 C, and a crystallization temperature (Tcrys) of
greater than 60 C, or from about 60 to about 140 C, or from about 65 to
about 120 C. The AT between Tmeit and Tuys is less than about 55 C.
[0052] The crystalline component may comprise amide, aromatic ester,
ester of an aliphatic linear diacid, urethanes, sulfones, or mixtures thereof.
[0053] Suitable crystalline components include those disclosed in U.S.
Patent Application Ser. No. _________ to Morimitsu et al. (Attorney
Docket No. 20110665-397243), entitled "Phase Change Ink Comprising
Crystalline Amides," which is hereby incorporated by reference in its
entirety.
These crystalline materials comprise the following structure:
CA 02813472 2013-04-19
. .
H
R8--_. N-....._
R9
0
Formula IV
wherein R8 and Rg can be the same or different, each R8 and Rg is
independently selected from the group consisting of (i) an alkyl group, which
can be a linear or branched, cyclic or acyclic, substituted or unsubstituted,
saturated or unsaturated, alkyl group, and wherein heteroatoms may
optionally be present in the alkyl group, in embodiments, having from about 1
to about 40 carbon atoms, from about 1 to about 20 carbon atoms, or from
about 1 to about 10 carbon atoms, (ii) an arylalkyl group, which can be a
substituted or unsubstituted arylalkyl group, wherein the alkyl portion of
arylalkyl group can be linear or branched, cyclic or acyclic, substituted or
unsubstituted, saturated or unsaturated, and wherein heteroatoms may
optionally be present in either the aryl portion or the alkyl portion of the
arylalkyl group, in embodiments, having from about 4 to about 40 carbon
atoms, from about 7 to about 20 carbon atoms, or from about 7 to about 12
carbon atoms; and (iii) an aromatic group, which can be a substituted or
unsubstituted aromatic group, wherein the substituent can be a linear,
branched, cyclic or acyclic alkyl group and wherein heteroatoms may
optionally be present in the aromatic group, having from about 3 to about 40
carbon atoms, from about 6 to about 20 carbon atoms, or from about 6 to
about 10 carbon atoms.
[0054] Suitable crystalline components include those disclosed
in U.S.
Patent Application Ser. No. ____________________ to Morimitsu et al. (Attorney
Docket No. 20110362-396157), entitled "Phase Change Ink Compositions
Comprising Aromatic Ethers," which is hereby incorporated by reference in its
entirety. These crystalline materials comprise the following structure:
R10 -0 ¨[(C1-12)20]p¨R11
Formula V
wherein R10 and R11 can be the same or different, and wherein each R10 and
R11 is independently selected from the group consisting of (i) an alkyl group,
which can be a linear or branched, cyclic or acyclic, substituted or
unsubstituted, saturated or unsaturated, alkyl group, and wherein
16
CA 02813472 2013-04-19
heteroatoms may optionally be present in the alkyl group, in embodiments,
having from about 1 to about 40 carbon atoms, from about 1 to about 20
carbon atoms, or from about 1 to about 10 carbon atoms; (ii) an arylalkyl
group, which can be a substituted or unsubstituted arylalkyl group, wherein
the alkyl portion of arylalkyl group can be linear or branched, cyclic or
acyclic,
substituted or unsubstituted, saturated or unsaturated, and wherein
heteroatoms may optionally be present in either the aryl portion or the alkyl
portion of the arylalkyl group, in embodiments, having from about 4 to about
40 carbon atoms, from about 7 to about 20 carbon atoms, or from about 7 to
about 12 carbon atoms; and (iii) an aromatic group, which can be a
substituted or unsubstituted aromatic group, wherein the substituent can be a
linear, branched, cyclic or acyclic alkyl group and wherein heteroatoms may
optionally be present in the aromatic group, having from about 3 to about 40
carbon atoms, or about 6 to about 20 carbon atoms, or from about 6 to about
carbon atoms, although the numbers can be outside of these ranges, and
mixtures thereof, provided that at least one of R10 and R11 is an aromatic
group; and p is 0 or 1.
[0055] Non-limited examples of crystalline aromatic ether include
S.0 so 0 HO iso 0.-= 40
, NC 7 HO
HO = = -01
,H3c c.3 , Ho OH ,
H2N
0 is
HO IIIII" , and mixtures thereof.
[0056] Suitable crystalline components include those disclosed in in
U.S. Patent Application Ser. No. ________ to Chopra et al. (Attorney
Docket No. 20101094-390676), entitled "Phase Change Inks and Methods of
Making the Same" which is hereby incorporated by reference in its entirety.
These crystalline materials comprise an ester of an aliphatic linear diacid
having the following structure:
R130 R12 OR14
17
CA 02813472 2013-04-19
Formula VI
wherein R12 may be substituted or unsubstituted alkyl chain and is selected
from the group consisting of - (CH2)1- to - (CH2)12-, and wherein R13 and R14,
each independently of the other, is selected from the group consisting of a
substituted or unsubstituted aromatic or heteroaromatic group, subtituents
including
alkyl groups, wherein the alkyl portion can be straight, branched or cyclic.
[0057] Suitable
crystalline components include those disclosed in U.S.
Patent Application Ser. No. _______________________________________ to Chopra
et al. (Attorney Docket
No. 20110356-396152), entitled "Phase Change Ink Compositions Comprising
Diurethanes and Derivatives Thereof," which is hereby incorporated by
reference in its entirety. These crystalline materials comprise diurethanes
having the following structure:
R15-4o),-(cH2)p¨oAN¨Q¨til / 0 CH2)q-A0),-Ri6
Formula VII
wherein Q is alkanediyl; each R15 and R16 is independently phenyl or
cyclohexyl optionally substituted with one or more alkyl; i is 0 or 1; j is 0
or 1; p
is 1 to 4; q is 1 to 4. In certain of such embodiments, each R15 and R16 is
independently phenyl or cyclohexyl optionally substituted with one or more
methyl or ethyl. In certain of such embodiments, R15 and R16 is phenyl. In
certain embodiments, Q is -(CH2)n- and n is 4 to 8. In certain of such
embodiments, n is 6. In certain embodiments, each R15 and R16, is
independently selected from benzyl, 2-phenylethyl, 2-phenoxyethyl,
C6H5(CH2)4-, cyclohexyl, 2-methylcyclohexyl, 3-phenylpropanyl, 3-
methylcyclohexyl, 4-methylcyclohexyl, cyclohexylmethyl, 2-
methylcyclohexylmethyl, 3-methylcyclohexylmethyl, 4-
methylcyclohexylrnethyl, and 4-ethylcyclohexanyl.
[0058] Suitable
crystalline components include those disclosed in U.S.
Patent Application Ser. No. __________ to Morimitsu et al. (Attorney
Docket No. 20110561-396152), entitled "Phase change ink Compositions
Comprising Crystalline Sulfone Compounds and Derivatives Thereof" which is
18
CA 02813472 2013-04-19
hereby incorporated by reference in its entirety. These crystalline component
being a sulfone compound having the following structure:
R17 -S02 --R18
Formula VIII
wherein R17 and R18 can be the same or different, and wherein R17 and R18
each, independently of the other is selected from the group consisting of (i)
an
alkyl group, which can be a linear or branched, cyclic or acyclic, substituted
or
unsubstituted, saturated or unsaturated, alkyl group, and wherein
heteroatoms may optionally be present in the alkyl group, in embodiments,
having from about 1 to about 40 carbon atoms, from about 1 to about 20
carbon atoms, or from about 1 to about 10 carbon atoms, although the
numbers can be outside of these ranges, (ii) an arylalkyl group, which can be
a substituted or unsubstituted arylalkyl group, wherein the alkyl portion of
arylalkyl group can be linear or branched, cyclic or acyclic, substituted or
unsubstituted, saturated or unsaturated, and wherein heteroatoms may
optionally be present in either the aryl portion or the alkyl portion of the
arylalkyl group, in embodiments, having from about 4 to about 40 carbon
atoms, from about 7 to about 20 carbon atoms, or from about 7 to about 12
carbon atoms, although the numbers can be outside of these ranges; and (iii)
an aromatic group, which can be a substituted or unsubstituted aromatic
group, wherein the substituent can be a linear, branched, cyclic or acyclic
alkyl group and wherein heteroatoms may optionally be present in the
aromatic group, having from about 3 to from about 40 carbon atoms, from
about 6 to about 20 carbon atoms, or about 6 to about 10 carbon atoms,
although the numbers can be outside of these ranges, and mixtures thereof.
[0059] In
certain embodiments, each R17 and R18 is independently alkyl,
or aryl, optionally substituted with one or more halo, amino, hydroxy, or
cyano
groups and combinations thereof, or R17 and R18 taken together with the S
atom to which they are attached form a heterocyclic ring. In certain of such
embodiments, each R17 and R18 is independently an optionally substituted
alkyl, such as, methyl, ethyl, isopropyl, n-butyl, or t-butyl. In certain of
such
embodiments, each R6 and R7 is independently an optionally substituted aryl,
such as, phenyl, or benzyl. In certain embodiments, each R17 and R18 is
19
CA 02813472 2013-04-19
4
independently substituted with one or more amino, chloro, fluoro, hydroxy,
cyano or combinations thereof. Substitution on the aryl groups may be made
in the ortho, meta or para position of the phenyl groups and combinations
thereof. In certain embodiments, each R17 and Rig is independently 2-
hydroxyethyl, or cyanomethyl.
[0060] In certain embodiments, the crystalline component may include
diphenyl sulfone, dimethyl sulfone, bis(4-hydroxyphenyl) sulfone, bis(4-
aminophenyl) sulfone, bis(3-aminophenyl) sulfone, bis(4-chlorophenyl)
sulfone, bis(4-fluorophenyl) sulfone, 2-hycroxypheny1-4-hydroxyphenyl
sulfone, phenyl-4-chlorophenyl sulfone, phenyl-2-aminophenyl sulfone, bis(3-
amino-4-hydroxyphenyl) sulfone, dibenzyl sulfone, methylethyl sulfone, diethyl
sulfone, methylisopropyl sulfone, ethylisopropyl sulfone, di-n-butyl sulfone,
divinyl sulfone, methyl-2-hydroxymethyl sulfone, methylchloromethyl sulfone,
sulfolane, 3-sulfolene, and mixtures thereof.
[0061] In certain embodiments, the phase change ink may comprise a
crystallization accelerating additive such as an organic pigment, an inorganic
nucleating additive or a fatty acid.
[0062] ORGANIC PIGMENTS
[0063] In some embodiments, suitable crystallization accelerators
include organic pigments. Suitable organic pigments are disclosed in U.S.
Patent Application Serial No. _________________ (not yet assigned) entitled
"Phase Change Inks Comprising Organic Pigments" to Jennifer Belelie et al.,
electronically filed on the same day herewith (Attorney Docket No. 20110418-
399388). Suitable organic pigments include but are not limited to include
Carbon Black, Pigment Blue 15, Pigment Blue 15:1, Pigment Blue 15:2,
Pigment Blue 15:3, Pigment Blue 15:4, Pigment Blue 15:6, Pigment Blue 1,
Pigment Blue 10, Pigment Blue 14, Pigment Blue 60, Pigment Blue 61,
Pigment Yellow 1, Pigment Yellow 3, Pigment Yellow 12, Pigment Yellow 13,
Pigment Yellow 14, Pigment Yellow 17, Pigment Yellow 24, Pigment Yellow
55, Pigment Yellow 62, Pigment Yellow 63, Pigment Yellow 65, Pigment
Yellow 73, Pigment Yellow 74, Pigment Yellow 81, Pigment Yellow 83,
Pigment Yellow 93, Pigment Yellow 95, Pigment Yellow 97, Pigment Yellow
110, Pigment Yellow 111, Pigment Yellow 123, Pigment Yellow 126, Pigment
Yellow 127, Pigment Yellow 139, Pigment Yellow 147, Pigment Yellow 150,
CA 02813472 2013-04-19
. .
Pigment Yellow 151, Pigment Yellow 154, Pigment Yellow 155, Pigment
Yellow 168, Pigment Yellow 170, Pigment Yellow 174, Pigment Yellow 175,
Pigment Yellow 176, Pigment Yellow 179, Pigment Yellow 180, Pigment
Yellow183, Pigment Yellow 185, Pigment Yellow 188, Pigment Yellow 191,
Pigment Yellow 194, Pigment Yellow 214, Pigment Red 2, Pigment Red 3,
Pigment Red 4, Pigment Red 5, Pigment Red 8, Pigment Red 9, Pigment Red
12, Pigment Red 13, Pigment Red 21, Pigment Red 22, Pigment Red 23,
Pigment Red 31, Pigment Red 32, Pigment Red 48:1, Pigment Red 48:2,
Pigment Red 48:3, Pigment Red 48:4, Pigment Red 49:1, Pigment Red 49:2,
Pigment Red 52:1, Pigment Red 52:2, Pigment Red 53:1, Pigment Red 53:3,
Pigment Red 57:1, Pigment Red 63:1, Pigment Red 81, Pigment Red 112,
Pigment Red 122, Pigment Red 123, Pigment Red 144, Pigment Red 146,
Pigment Red 149, Pigment Red 166, Pigment Red 169, Pigment Red 170,
Pigment Red 171, Pigment Red 175, Pigment Red 176, Pigment Red 177,
Pigment Red 178, Pigment Red 179, Pigment Red 184, Pigment Red 185,
Pigment Red 188, Pigment Red 189, Pigment Red 202, Pigment Red 208,
Pigment Red 210, Pigment Red 224. Pigment Red 242, Pigment Red 245,
Pigment Red 254, Pigment Red 266, Pigment Red 268, Pigment Red 269,
Pigment Orange 5, Pigment Orange 13, Pigment Orange 16, Pigment Orange
34, Pigment Orange 36, Pigment Orange 63, Pigment Violet 1, Pigment Violet
2, Pigment Violet 3, Pigment Violet 19, Pigment Violet 23, Pigment Violet 27,
Pigment Green 7, Pigment Green 36, all listed in the Color Index publication
by the Society of Dyers and Colourists and the American Association of
Textile Chemists and Colorists
[0064] Specific examples of suitable commercially available
organic
pigments include, but are not limited to, PALIOGEN Violet 5100 (BASF);
PALIOGEN Violet 5890 (BASF); HELIOGEN Green L8730 (BASF); LITHOL
Scarlet D3700 (BASF); SUNFAST Blue 15:4 (Sun Chemical); Hostaperm Blue
B2G-D (Clariant); Permanent Red P-F7RK; Hostaperm Violet BL (Clariant);
LITHOL Scarlet 4440 (BASF); Bon Red C (Dominion Color Company);
ORACET Pink RF (BASF); PALIOGEN Red 3871 K (BASF); SUNFAST Blue
15:3 (Sun Chemical); PALIOGEN Red 3340 (BASF); SUNFAST Carbazole
Violet 23 (Sun Chemical); LITHOL Fast Scarlet L4300 (BASF); SUNBRITE
Yellow 17 (Sun Chemical); HELIOGEN Blue L6900, L7020 (BASF);
21
CA 02813472 2013-04-19
. .
SUNBRITE Yellow 74 (Sun Chemical); SPECTRA PAC C Orange 16 (Sun
Chemical); HELIOGEN Blue K6902, K6910 (BASF); SUNFAST Magenta 122
(Sun Chemical); HEL1OGEN Blue D6840, D7080 (BASF); Sudan Blue OS
(BASF); NEOPEN Blue FF4012 (BASF); PV Fast Blue B2G01 (Clariant);
IRGALITE Blue BCA (BASF); PALIOGEN Blue 6470 (BASF); Sudan Orange
G (Aldrich), Sudan Orange 220 (BASF); PALIOGEN Orange 3040 (BASF);
PALIOGEN Yellow 152, 1560 (BASF); LITHOL Fast Yellow 0991 K (BASF);
PALIOTOL Yellow 1840 (BASF); NOVOPERM Yellow FGL (Clariant);
Lumogen Yellow D0790 (BASF); Suco-Yellow L1250 (BASF); Suco-Yellow
D1355 (BASF); Suco Fast Yellow DI 355, DI 351 (BASF); HOSTAPERM Pink
E 02 (Clariant); Hansa Brilliant Yellow 5GX03 (Clariant); Permanent Yellow
GRL 02 (Clariant); Permanent Rubine L6B 05 (Clariant); FANAL Pink D4830
(BASF); CINQUASIA Magenta (DU PONT); PALIOGEN Black L0084 (BASF);
Pigment Black K801 (BASF); and carbon blacks such as REGAL 33QTM
(Cabot), Carbon Black 5250, Carbon Black 5750 (Columbia Chemical),
mixtures thereof and the like. In one embodiment, the ink may contain one
organic pigment. In another embodiment, the ink may contain a mixture of at
least two different organic pigments.
[0065] In specific embodiments, the pigment is present in the
ink
composition in an amount of at least from about 0.1 percent to about 50
percent by weight, or at least from about 0.5 percent to about 20 percent by
weight, from about 0.5 percent to about 10 percent, from about 1 percent to
about 5 percent by weight of the total weight of the ink composition.
[0066] Typically the organic pigment particle suitable for use
in
according to the present disclosure have an average particle size of from 10
nm to 400 nm, more specifically a particle size of from 50 nm to 300 nm, or
from 80 nm to 250 nm.
[0067] INORGANIC PIGMENTS
[0068] In some embodiments, suitable crystallization
accelerators
include inorganic nucleating nanoparticle materials. Fast crystallizing
crystalline-amorphous inks comprising inorganic pigment materials as
crystallization accelerators are disclosed in U.S. Patent Application Serial
No.
_________________________ (not yet assigned) entitled "Phase Change Inks
Comprising
Inorganic Nucleating Agents" to Daryl W. Vanbesien et al., electronically
filed
22
CA 02813472 2013-04-19
. .
on the same day herewith (Attorney Docket No. 20111206-400896). The
inorganic nucleating agent is selected from a group consisting of silica,
silica
dioxide, alumina, zinc oxide, inorganic oxides, talc, barium, calcium, sodium,
lithium, aluminum, and mixtures thereof.
[0069] In certain embodiments, inorganic nucleating agents are
nanoparticles. Inorganic nucleating agent particle size typically ranges from
2
nanometers (nm) to about 300 nm. In one embodiment, the ink composition
comprises inorganic nucleating agent particles having a particle size of about
nm to about 100 nm.
[0070] Typically, the inorganic nucleating agent is present in
amounts
from about 0.1 to about 10 weight percent, from about 0.5 to about 5 weight
percent, or from about 1 to about 3 weight percent based on the total weight
of the ink composition
[0071] FATTY ACID
[0072] In some embodiments, the crystallization accelerator is
a fatty
acid. Such fast crystallizing crystalline-amorphous compositions containing a
fatty organic acid are disclosed in U.S. Patent Application Serial No.
_________________________ (not yet assigned) entitled "Phase Change Inks
Comprising
Fatty Acids" to Gabriel Iftime et al., electronically filed on the same day
herewith (Attorney Docket No. 20110815-399390).
[0073] Specific non-limiting examples of suitable fatty acids
include, but
are not limited to, palmitic acid (hexadecanoic acid), palmitoleic acid (9-
hexadecenoic acid), stearic acid (octadecanoic acid), oleic acid (9-
octadecenoic acid), ricinoleic acid (12-hydroxy-9-octadecenoic acid), vaccenic
acid (11-octadecenoic acid), linoleic acid (9,12-octadecadienoic acid), alpha-
linolenic acid (9,12,15-octadecatrienoic acid), gamma-linolenic acid (6,9,12-
octadecatrienoic acid), arachidic acid (eicosanoic acid), gadoleic acid (9-
eicosenoic acid), arachidonic acid (5,8,11,14-eicosatetraenoic acid), erucic
acid (13-docosenoic acid), and mixtures thereof. In certain embodiments, the
fatty acid is stearic acid. In certain embodiments, the fatty acid is behenic
acid.
[0074] The percentage by weight of the fatty acid in an ink
composition
of the invention can be between about 0.1 % and 25 %, between about 1 %
and 15 %, or between about 2 % and 10%.
23
CA 02813472 2013-04-19
[0075] In certain embodiments, a phase change ink composition
comprises a blend of a crystalline component and an amorphous component,
generally in a weight ratio of from about 60:40 to about 95:5, respectively.
In
more specific embodiments, the weight ratio of the crystalline to amorphous
component is from about 65:35 to about 95:5, or is from about 70:30 to about
90:10, or is from about 70:30 to about 80:20. In other embodiments, the
crystalline and amorphous components are blended in a weight ratio of from
about 1.5 to about 20 or from about 2.0 to about 10, respectively. Each
component imparts specific properties to the phase change inks, and the
blend of the components provides inks that exhibit excellent robustness on
uncoated and coated substrates. The crystalline component in the ink
formulation drives the phase change through rapid crystallization on cooling.
The crystalline component also sets up the structure of the final ink film and
creates a hard ink by reducing the tackiness of the amorphous component.
The amorphous components provide tackiness and impart robustness to the
printed ink.
[0076] The crystalline and amorphous materials of the present
embodiments were found to be miscible with one another and the resulting ink
compositions formulated with the crystalline and amorphous materials show
good rheological profiles. Image samples created by the phase change ink
composition on coated paper by K-proof exhibit excellent robustness. A K-
proofer is a common test fixture in a print shop. The present embodiments
comprise a balance of amorphous and crystalline materials to realize a sharp
phase transition from liquid to solid and facilitate hard and robust printed
images, while maintaining a desired level of viscosity. Prints made with this
ink demonstrated advantages over commercially available inks, such as for
example, better robustness against scratch.
[0077] In embodiments, in the molten state, the resulting solid ink has a
viscosity of from about 1 to about 22 cps, or from about 4 to about 15 cps, or
from about 6 to about 12 cps, at a the jetting temperature. The jetting
temperature is typically comprised in a range from about 100 C to about
140 C. In embodiments, the solid ink has a viscosity of about > 106 cps, at
room temperature. In embodiments, the solid ink has a Tmot of from about 65
to about 150 C, or from about 70 to about 140 C, from about 80 to about
24
CA 02813472 2013-04-19
4 .
135 C and a 'rays of from about 40 to about 140 C, or from about 45 to about
130 C, from about 50 to about 120 C, as determined by DSC at a rate of 10
C/min.
[0078] The ink of embodiments may further include conventional
additives to take advantage of the known functionality associated with such
conventional additives. Such additives may include, for example, at least one
antioxidant, defoamer, slip and leveling agents, clarifier, viscosity
modifier,
adhesive, plasticizer and the like.
[0079] The ink may optionally contain antioxidants to protect
the
images from oxidation and also may protect the ink components from
oxidation while existing as a heated melt in the ink reservoir. Examples of
suitable antioxidants include N,N'-hexamethylene bis(3,5-di-tert-buty1-4-
hydroxy hydrocinnamamide) (IRGANOX 1098, available from BASF), 2,2-
bis(4-(2-(3,5-di-tert-buty1-4-hydroxyhydrocinnamoyloxy))
ethoxyphenyl)propane (TOPANOL-205, available from Vertellus), tris(4-tert-
buty1-3-hydroxy-2,6-dimethyl benzyl)isocyanurate (Aldrich), 2,2'-ethylidene
bis(4,6-di-tert-butylphenyl)fluoro phosphonite (ETHANOX-398, available from
Albermarle Corporation), tetrakis(2,4-di-tert-butylpheny1)-4,4'-biphenyl
diphosphonite (ALDRICH 46), pentaerythritol tetrastearate (TCI America),
tributylammonium hypophosphite (Aldrich), 2,6-di-tert-buty1-4-methoxyphenol
(Aldrich), 2,4-di-tert-buty1-6-(4-methoxybenzyl)phenol (Aldrich), 4-bromo-2,6-
dimethylphenol (Aldrich), 4-bromo-3,5-didimethylphenol (Aldrich), 4-bromo-2-
nitrophenol (Aldrich), 4-(diethyl aminomethyl)-2,5-dimethylphenol (Aldrich), 3-
dimethylaminophenol (Aldrich), 2-amino-4-tert-amylphenol (Aldrich), 2,6-
bis(hydroxymethyl)-p-cresol (Aldrich), 2,2'-methylenediphenol (Aldrich), 5-
(diethylamino)-2-nitrosophenol (Aldrich), 2,6-dichloro-4-fluorophenol
(Aldrich),
2,6-dibromo fluoro phenol (Aldrich), a-trifluoro-o-cresol (Aldrich), 2-bromo-4-
fluorophenol (Aldrich), 4-fluorophenol (Aldrich), 4-chloropheny1-2-chloro-
1,1,2-
tri-fluoroethyl sulfone (Aldrich), 3,4-difluoro phenylacetic acid (Adrich), 3-
fluorophenylacetic acid (Aldrich), 3,5-difluoro phenylacetic acid (Aldrich), 2-
fluorophenylacetic acid (Aldrich), 2,5-bis (trifluoromethyl) benzoic acid
(Aldrich), ethyl-2-(4-(4-(trifluoromethyl)phenoxy)phenoxy)propionate
(Aldrich),
tetrakis (2,4-di-tert-butyl phenyl)-4,4'-biphenyl diphosphonite (Aldrich), 4-
tert-
amyl phenol (Aldrich), 3-(2H-benzotriazol-2-y1)-4-hydroxy phenethylalcohol
CA 02813472 2013-04-19
. ,
(Aldrich), NAUGARD 76, NAUGARD 445, NAUGARD 512, AND NAUGARD
524 (manufactured by Chemtura Corporation), and the like, as well as
mixtures thereof. The antioxidant, when present, may be present in the ink in
any desired or effective amount, such as from about 0.25 percent to about 10
percent by weight of the ink or from about 1 percent to about 5 percent by
weight of the ink.
[0080] In embodiments, the phase change ink compositions
described
herein may also include a colorant. Any desired or effective colorant can be
employed in the phase change ink compositions, including dyes, pigments,
mixtures thereof, and the like, provided that the colorant can be dissolved or
dispersed in the ink carrier. Any dye or pigment may be chosen, provided that
it is capable of being dispersed or dissolved in the ink carrier and is
compatible with the other ink components. The phase change carrier
compositions can be used in combination with conventional phase change ink
colorant materials, such as Color Index (C.I.) Solvent Dyes, Disperse Dyes,
modified Acid and Direct Dyes, Basic Dyes, Sulphur Dyes, Vat Dyes, and the
like. Examples of suitable dyes include Neozapon Red 492 (BASF); Orasol
Red G (Pylam Products); Direct Brilliant Pink B (Oriental Giant Dyes); Direct
Red 3BL (Classic Dyestuffs); Supranol Brilliant Red 3BW (Bayer AG); Lemon
Yellow 6G (United Chemie); Light Fast Yellow 3G (Shaanxi); Aizen Spilon
Yellow C-GNH (Hodogaya Chemical); Bemachrome Yellow GD Sub (Classic
Dyestuffs); Cartasol Brilliant Yellow 4GF (Clariant); Cibanone Yellow 2G
(Classic Dyestuffs); Orasol Black RLI (BASF); Orasol Black CN (Pylam
Products); Savinyl Black RLSN (Clariant); Pyrazol Black BG (Clariant);
Morfast Black 101 (Rohm & Haas); Diaazol Black RN (ICI); Thermoplast Blue
670 (BASF); Orasol Blue GN (Pylam Products); Savinyl Blue GLS (Clariant);
Luxol Fast Blue MBSN (Pylam Products); Sevron Blue 5GMF (Classic
Dyestuffs); Basacid Blue 750 (BASF); Keyplast Blue (Keystone Aniline
Corporation); Neozapon Black X51 (BASF); Classic Solvent Black 7 (Classic
Dyestuffs); Sudan Blue 670 (C.I. 61554) (BASF); Sudan Yellow 146 (C.I.
12700) (BASF); Sudan Red 462 (C.I. 26050) (BASF); C.I. Disperse Yellow
238; Neptune Red Base NB543 (BASF, al. Solvent Red 49); Neopen Blue
FF-4012 (BASF); Lampronol Black BR (C.I. Solvent Black 35) (ICI); Morton
Morplas Magenta 36 (C.I. Solvent Red 172); metal phthalocyanine colorants
26
CA 02813472 2013-04-19
v =
such as those disclosed in U.S. Pat. No. 6,221,137, the disclosure of which is
totally incorporated herein by reference, and the like. Polymeric dyes can
also
be used, such as those disclosed in, for example, U.S. Pat. No. 5,621,022
and U.S. Pat. No. 5,231,135, the disclosures of each of which are herein
entirely incorporated herein by reference, and commercially available from,
for
example, Milliken & Company as Milliken Ink Yellow 869, Milliken Ink Blue 92,
Milliken Ink Red 357, Milliken Ink Yellow 1800, Milliken Ink Black 8915-67,
uncut Reactint Orange X-38, uncut Reactint Blue X-17, Solvent Yellow 162,
Acid Red 52, Solvent Blue 44, and uncut Reactint Violet X-80.
[0081] Pigments are also suitable colorants for the phase
change inks.
Examples of suitable pigments include PALIOGEN Violet 5100 (BASF);
PALIOGEN Violet 5890 (BASF); HELIOGEN Green L8730 (BASF); LITHOL
Scarlet D3700 (BASF); SUNFAST Blue 15:4 (Sun Chemical); Hostaperm Blue
B2G-D (Clariant); Hostaperm Blue B4G (Clariant); Permanent Red P-F7RK,
Hostaperm Violet BL (Clariant); LITHOL Scarlet 4440 (BASF); Bon Red C
(Dominion Color Company); ORACET Pink RF (BASF); PALIOGEN Red 3871
K (BASF); SUNFAST Blue 15:3 (Sun Chemical); PALIOGEN Red 3340
(BASF); SUNFAST Carbazole Violet 23 (Sun Chemical); LITHOL Fast Scarlet
L4300 (BASF); SUNBRITE Yellow 17 (Sun Chemical); HELIOGEN Blue
L6900, L7020 (BASF); SUNBRITE Yellow 74 (Sun Chemical); SPECTRA
PAC C Orange 16 (Sun Chemical); HELIOGEN Blue K6902, K6910 (BASF);
SUNFAST Magenta 122 (Sun Chemical); HELIOGEN Blue D6840, D7080
(BASF); Sudan Blue OS (BASF); NEOPEN Blue FF4012 (BASF); PV Fast
Blue B2G01 (Clariant); IRGALITE Blue GLO (BASF); PALIOGEN Blue 6470
(BASF); Sudan Orange G (Aldrich), Sudan Orange 220 (BASF); PALIOGEN
Orange 3040 (BASF); PALIOGEN Yellow 152, 1560 (BASF); LITHOL Fast
Yellow 0991 K (BASF); PALIOTOL Yellow 1840 (BASF); NOVOPERM Yellow
FGL (Clariant); Ink Jet Yellow 4G VP2532 (Clariant); Toner Yellow HG
(Clariant); Lumogen Yellow D0790 (BASF); Suco-Yellow L1250 (BASF);
Suco-Yellow D1355 (BASF); Suco Fast Yellow D1355, D1351 (BASF);
HOSTAPERM Pink E 02 (Clariant); Hansa Brilliant Yellow 5GX03 (Clariant);
Permanent Yellow GRL 02 (Clariant); Permanent Rubine L6B 05 (Clariant);
FANAL Pink D4830 (BASF); CINQUASIA Magenta (DU PONT); PALIOGEN
Black L0084 (BASF); Pigment Black K801 (BASF); and carbon blacks such as
27
CA 02813472 2013-04-19
. .
REGAL 330TM (Cabot), Nipex 150 (Evonik) Carbon Black 5250 and Carbon
Black 5750 (Columbia Chemical), and the like, as well as mixtures thereof.
[0082] Pigment dispersions in the ink base may be stabilized by
synergists and dispersants. Generally, suitable pigments may be organic
materials or inorganic.
[0083] Also suitable are the colorants disclosed in U.S. Pat.
No.
6,472,523, U.S. Pat. No. 6,726,755, U.S. Pat. No. 6,476,219, U.S. Pat. No.
6,576,747, U.S. Pat. No. 6,713,614, U.S. Pat. No. 6,663,703, U.S. Pat. No.
6,755,902, U.S. Pat. No. 6,590,082, U.S. Pat. No. 6,696,552, U.S. Pat. No.
6,576,748, U.S. Pat. No. 6,646,111, U.S. Pat. No. 6,673,139, U.S. Pat. No.
6,958,406, U.S. Pat. No. 6,821,327, U.S. Pat. No. 7,053,227, U.S. Pat. No.
7,381,831 and U.S. Pat. No. 7,427,323, the disclosures of each of which are
incorporated herein by reference in their entirety.
[0084] In embodiments, solvent dyes are employed. An example of
a
solvent dye suitable for use herein may include spirit soluble dyes because of
their compatibility with the ink carriers disclosed herein. Examples of
suitable
spirit solvent dyes include Neozapon Red 492 (BASF); Orasol Red G (Pylam
Products); Direct Brilliant Pink B (Global Colors); Aizen Spilon Red C-BH
(Hodogaya Chemical); Kayanol Red 3BL (Nippon Kayaku); Spirit Fast Yellow
3G; Aizen Spilon Yellow C-GNH (Hodogaya Chemical); Cartasol Brilliant
Yellow 4GF (Clariant); Pergasol Yellow 5RA EX (Classic Dyestuffs); Orasol
Black RLI (BASF); Savinyl Black RLS (Clariant); Morfast Black 101 (Rohm
and Haas); Orasol Blue GN (Pylam Products); Thermoplast Blue 670 (BASF);
Savinyl Blue GLS (Sandoz); Luxol Fast Blue MBSN (Pylam); Sevron Blue
5GMF (Classic Dyestuffs); Basacid Blue 750 (BASF); Keyplast Blue E
(Keystone Aniline Corporation); Neozapon Black X51 (C.I. Solvent Black, C.1.
12195) (BASF); Sudan Blue 670 (C.I. 61554) (BASF); Sudan Yellow 146 (C.I.
12700) (BASF); Sudan Red 462 (C.I. 260501) (BASF), mixtures thereof and
the like.
[0085] The colorant may be present in the phase change ink in
any
desired or effective amount to obtain the desired color or hue such as, for
example, at least from about 0.1 percent by weight of the ink to about 50
percent by weight of the ink, at least from about 0.2 percent by weight of the
28
CA 02813472 2013-04-19
. ,
ink to about 20 percent by weight of the ink, and at least from about 0.5
percent by weight of the ink to about 10 percent by weight of the ink.
[0086] In embodiments, in the molten state, the ink carriers
for the
phase change inks may have a viscosity of from about 1 to about 22 cps, or
from about 4 to about 15 cps, or from about 6 to about 12 cps, at a the
jetting
temperature. The jetting temperature is typically comprised in a range from
about 100 C to about 140 C. In embodiments, the solid ink has a viscosity of
about > 106 cps, at room temperature. In embodiments, the solid ink has a
Tmeft of from about 65 to about 140 C, or from about 70 to about 140 C, from
about 80 to about 135 C and a -rays of from about 40 to about 140 C, or from
about 45 to about 130 C, from about 50 to about 120 C, as determined by
DSC at a rate of 10 C/min.
[0087] The ink compositions can be prepared by any desired or
suitable method. For example, each of the components of the ink carrier can
be mixed together, followed by heating, the mixture to at least its melting
point, for example from about 60 C to about 150 C, 80 C to about 145 C
and 85 C to about 140 C. The colorant may be added before the ink
ingredients have been heated or after the ink ingredients have been heated.
When pigments are the selected colorants, the molten mixture may be
subjected to grinding in an attritor or ball mill apparatus or other high
energy
mixing equipment to affect dispersion of the pigment in the ink carrier. The
heated mixture is then stirred for about 5 seconds to about 30 minutes or
more, to obtain a substantially homogeneous, uniform melt, followed by
cooling the ink to ambient temperature (typically from about 20 C to about 25
C). The inks are solid at ambient temperature. In a specific embodiment,
during the formation process, the inks in their molten state are poured into
molds and then allowed to cool and solidify to form ink sticks. Suitable ink
preparation techniques are disclosed in U.S. Pat. No. 7,186,762, the
disclosure of which is incorporated herein by reference in its entirety.
[0088] The inks can be employed in apparatus for direct
printing ink jet
processes and in indirect (offset) printing ink jet applications. Another
embodiment disclosed herein is directed to a process which comprises
incorporating an ink as disclosed herein into an ink jet printing apparatus,
melting the ink, and causing droplets of the melted ink to be ejected in an
29
CA 02813472 2013-04-19
imagewise pattern onto a recording substrate. A direct printing process is
also
disclosed in, for example, U.S. Pat. No. 5,195,430, the disclosure of which is
totally incorporated herein by reference. Yet another embodiment disclosed
herein is directed to a process which comprises incorporating an ink as
disclosed herein into an ink jet printing apparatus, melting the ink, causing
droplets of the melted ink to be ejected in an imagewise pattern onto an
intermediate transfer member, and transferring the ink in the imagewise
pattern from the intermediate transfer member to a final recording substrate.
In a specific embodiment, the intermediate transfer member is heated to a
temperature above that of the final recording sheet and below that of the
melted ink in the printing apparatus. In another specific embodiment, both the
intermediate transfer member and the final recording sheet are heated; in this
embodiment, both the intermediate transfer member and the final recording
sheet are heated to a temperature below that of the melted ink in the printing
apparatus; in this embodiment, the relative temperatures of the intermediate
transfer member and the final recording sheet can be (1) the intermediate
transfer member is heated to a temperature above that of the final recording
substrate and below that of the melted ink in the printing apparatus; (2) the
final recording substrate is heated to a temperature above that of the
intermediate transfer member and below that of the melted ink in the printing
apparatus; or (3) the intermediate transfer member and the final recording
sheet are heated to approximately the same temperature. An offset or indirect
printing process is also disclosed in, for example, U.S. Pat. No. 5,389,958,
the
disclosure of which is totally incorporated herein by reference. In one
specific
embodiment, the printing apparatus employs a piezoelectric printing process
wherein droplets of the ink are caused to be ejected in imagewise pattern by
oscillations of piezoelectric vibrating elements. Inks as disclosed herein can
also be employed in other hot melt printing processes, such as hot melt
acoustic ink jet printing, hot melt thermal ink jet printing, hot melt
continuous
stream or deflection ink jet printing, and the like. Phase change inks as
disclosed herein can also be used in printing processes other than hot melt
ink jet printing processes.
[0089] In some situations it may be advantageous to provide an ink
which can be printed at high speeds. This requires inks which are capable of
CA 02813472 2013-04-19
=
solidifying very fast once placed onto the paper, in order to prevent offset
of
the printed image during fast printing process.
[0090] Any suitable substrate or recording sheet can be
employed,
including coated and plain paper. Coated paper includes silica coated papers
such as Sharp Company silica coated paper, JuJo paper, HAMMERMILL
LASERPRINT paper, and the like, glossy coated papers such as XEROX
Digital Color Elite Gloss, Sappi Warren Papers LUSTROGLOSS, specialty
papers such as Xerox DURAPAPER, and the like. Plain paper includes such
as XEROX 4200 papers, XEROX Image Series papers, Courtland 4024 DP
paper, ruled notebook paper, bond paper. Transparency materials, fabrics,
textile products, plastics, polymeric films, inorganic recording mediums such
as metals and wood, may also be used.
[0091] The inks described herein are further illustrated in the
following
examples. All parts and percentages are by weight unless otherwise
indicated.
[0092] 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.
[0093] While the description above refers to particular
embodiments, it
will be understood that many modifications may be made without departing
from the spirit thereof. The accompanying claims are intended to cover such
modifications as would fall within the true scope and spirit of embodiments
herein.
[0094] The presently disclosed embodiments are, therefore, to
be
considered in all respects as illustrative and not restrictive, the scope of
embodiments being indicated by the appended claims rather than the
foregoing description. All changes that come within the meaning of and range
of equivalency of the claims are intended to be embraced therein.
EXAMPLES
[0095] The examples set forth herein below and are illustrative
of
different compositions and conditions that can be used in practicing the
31
CA 02813472 2013-04-19
present embodiments. All proportions are by weight unless otherwise
indicated. It will be apparent, however, that the present embodiments can be
practiced with many types of compositions and can have many different uses
in accordance with the disclosure above and as pointed out hereinafter.
[0096] Example 1
[0097] Crystalline-Amorphous Formulations
[0098] Ink Preparation
[0099] 10 g of mixtures of the crystalline and amorphous materials
shown in Tables 1 and 2 were prepared by combining the two components at
the proportions shown in the tables (wt%) and stirred at 140 C for 30 minutes
to 1 hour. The crystallization rates of the crystalline materials were
measured
and the results are shown in Tables 1 and 2.
[00100] Rate of Crystallization (TROM results)
Table 1. TROM of fast crystallizing ink base formulations.
Sample Crystalline (%) Amorphous (%) T test T total
( C) (s)
1 =40 130 4.5
1C12, CCk j21
Diphenyt sulfone (DPS)
(80) tri-DL-menthyl
citrate (TMC) (20)
2 120 12
0
dibenzyl hexane-1,6-
0 6H
diyldicarbamate (70) di-DL-menthyl L-
tartrate (DMT) (30)
111 01-1 0
100;
di-p-tolyl octanedioate 0 6H 120;
(80) DMT (20) 140
4
120.
- 7
OH 0
140
0 OH
bis(4-methoxyphenyl) DMT (20)
octanedioate (80)
Table 2. TROM of slow crystallizing ink base formulations.
Sample Crystalline (%) Amorphous (%) T test T total
( C) (s)
32
CA 02813472 2013-04-19
OH 0Y OH 120 175
0
* 0 OH 1 0 00 µ1
Diphenethyl L-
Tartrate, DPT (80) TMC (20)
6 H 9 n 115 20-28
0 OH [24]
DPT (80) DMT (20)
7 0
115 310
00,,00
,r3)
N1,N2,N3-tributy1-2- TMC (30)
hydroxypropane-
1,2,3-tricarboxamide
(70)
[00101] Discussion: Fast
Crystallizing Formulations
[00102] All of the samples (#1-4) described in Table 1 exhibited fast
crystallization time, T total (< 15 s) under TROM test conditions. The
crystalline components contain aryl or arylalkyl groups and the amorphous
components contain only aliphatic groups and the core structures of the
crystalline and amorphous components are different.
[00103] Discussion: Slow Crystallizing Formulations (counter examples)
[00104] All samples shown in Table 2 have a slow or very slow T total (>
20 s) under TROM test conditions.
[00105] As shown in Tables 1 and 2, fast crystallization is not an
inherent property of a crystalline-amorphous ink composition. Some
crystalline-amorphous formulations demonstrate fast crystallizing property,
while some crystalline-amorphous formulations demonstrate slow crystallizing
property.
[00106] Example 2
[00107] Crystalline-Amorphous Formulations with Crystallization
Accelerators:
[00108] Preparation of Ink Samples
[00109] DMT was used as the amorphous compound and DPT was
used as the crystalline compound in the ink-based formulations. The mixture
of DMT and DPT were stirred in the molten state at 140 C without dye, then
cooled down to obtain the ink base samples. The crystalline:amorphous ratio
33
CA 02813472 2013-04-19
of the ink samples were roughly in the ratio of 80:20 in weight percent. The
crystalline and amorphous materials were well-miscible in this mixing ratio.
[00110] Ink formulations details are shown in Table 3.
[00111] Ink sample 6 contains DPI and DMT without any colorant.
Colored inks were prepared by adding dyes or pigments to the ink base
(sample 6).
[00112] Ink samples 8 contains a dye SB101 and was prepared by
mixing 2.475 g of ink sample 6 from above with 0.025 g of SB101 dye at a
temperature of 140 C.
[00113] Sample 9 contains an organic pigment package (pigment and
dispersant), prepared to the specifications shown in the Table 3.
[00114] Sample 10 is ink base 6 to which behenic acid was added as a
fatty acid crystallization accelerator. Sample 10 was prepared by combining
ink base 6 (2.375 g, 95wV/0) and behenic acid (0.125 g, 5wt%) and stirring at
140 C for 1 h. The sample was discharged into an aluminum pan and
allowed to cool.
[00115] Sample 11 is an ink containing an ink base meeting the
selection criteria for amorphous and crystalline such as to provide fast
crystallizing inks. The amorphous and crystalline components are the same
as those from sample 2 in Table 1, but at a higher proportion of crystalline
component. The sample contains 2% dye Solvent Blue 10. It is used as
baseline 2 ink base for testing acceleration effects of additives in samples
12
and 13
[00116] Sample 12 contains the Baseline ink 2 (#11) to which an
inorganic nucleating agent (silica nanoparticles) was added to the proportions
described in the Table 3.
[00117] Sample 13 contains the Baseline ink 2 (#11) to which an organic
pigment was added to the proportions described in Table 3. This sample
illustrates the synergistic effect on acceleration of the crystallization
rate.
Table 3. Ink formulations
Component Structure Ink Sample (wt %)
6 8 9 10 11 12 13
Di-phenethyl L-
80 79.2 76. 76.0
tartrate (DPT) 8
Crystalline
34
CA 02813472 2013-04-19
=
Di-DL-menthyl L- 20 19.8 19. 19.0
19.6 18.8 18.8
tartrate (DMT)
2
Amorphous
Dibenzyl 78.2
75.2 75.2
hexane-1,6-
diyIdicarbamate Crystalline Diurethane
SB101-Keyplast Dye 1.0 2.0
2.0 2.0
SpectraPAC Organic Pigment 2.0
EFKA 4340 Dispersant 2.0
Behenic Acid Fatty Acid 5.0
Silica Oxide Inorganic Nucleating
2.0
Agent
B4G cyan Organic Pigment
2.0
pigment
Solsperse 32000 Dispersant
2.0 2.0 -
[00118] TROM results (rate of crystallization)
Table 4 shows the rate of crystallization times for inks containing
crystallization accelerators from Example 2.
Table 2. Crystallization Times by TROM
Ink Tmelt T total(s) Effect on crystallization
6 115 24 baseline 1
8 115 107 deceleration
9 125 12 acceleration
120 7 acceleration
11 140 7 baseline ink 2
12 140 4 acceleration
13 140 5 acceleration
[00119] Tmeit is the temperature measured in centigrade degrees,
at
which the ink is molten for the TROM measurement, i.e. at which the TROM
cooling process starts. This temperature is typically chosen such as to be
identical to the ideal jetting temperature which is comprised in between 10 to
12 cps.
[00120] In all cases acceleration of the crystallization rate
was observed
when the crystallization accelerator was added:
[00121] Sample 8: Deceleration of the crystallization by
addition of a dye
(107 seconds) to a slow crystallizing ink base (Sample 6, 24 seconds), a
rather general problem encountered by the inventors.
CA 02813472 2013-04-19
= ,
[00122] Sample 9: Demonstrates acceleration of the
crystallization of Ink
Base from Sample 6 (24 seconds) by addition of an organic pigment package
(12 seconds).
[00123] Sample 10: Demonstrates acceleration of crystallization
of ink
base from Sample 6 (24 seconds) by the addition of a fatty acid
crystallization
accelerator (7 seconds).
[00124] Sample 11: Is an example of a fast crystallizing inks
made by
selecting the crystalline and amorphous components such as to meet the
selection criteria for reduced compatibility. Total crystallization time is
reduced
from 107 seconds (Sample 8) to 7 seconds.
[00125] Sample 12. Demonstrates acceleration of the
crystallization of
the Baseline ink 2 (7 seconds) by addition of an inorganic nucleating agent
(silica; 4 seconds).
[00126] Sample 13: Illustrates the synergetic effect: Combines
two
different approaches to fast crystallization: (a) Fast ink base (Baseline ink
2)
made according to selection criteria (Sample 11; 7 seconds) with (b) an
organic pigment package (Sample 9, 12 seconds) to provide an ink which is
faster than any of the two individual inks (5 seconds).
Example 3
Robustness demonstration of fast crystallizing ink
[00127] The inks #8 to #13 described in Table 3 were subsequently coated
using a K-printing proofer (manufactured by RK Print Coat Instrument Ltd.,
Litlington, Royston, Hens, SG8 00Z, U.K.) onto Xerox digital Color Elite
Gloss, 120gsm (DCEG) to form robust images that could not be easily
removed from the substrate.
[00128] When a scratch/gouge finger with a curved tip at an angle
of about
150 from vertical, with a weight of 528 g applied, was drawn across the
images at a rate of approximately 13 mm/s no ink was visibly removed from
the images. The scratch/gouge tip is similar to a lathe round nose cutting bit
with radius of curvature of approximately 12mm.
2.
[00129] The claims, as originally presented and as they may be
amended, encompass variations, alternatives, modifications, improvements,
36
CA 02813472 2013-04-19
equivalents, and substantial equivalents of the embodiments and teachings
disclosed herein, including those that are presently unforeseen or
unappreciated, and that, for example, may arise from applicants/patentees
and others. Unless specifically recited in a claim, steps or components of
claims should not be implied or imported from the specification or any other
claims as to any particular order, number, position, size, shape, angle,
color,
or material.
[00130] All the patents and applications referred to herein are hereby
specifically, and totally incorporated herein by reference in their entirety
in the
instant specification.
37
