U.S. patent application number 12/229150 was filed with the patent office on 2009-03-12 for nanoparticle-based compositions compatible with jet printing and methods therefor.
Invention is credited to Kevin J. Hook, Stanley Litman, Jeffrey Zaloom.
Application Number | 20090064884 12/229150 |
Document ID | / |
Family ID | 39809328 |
Filed Date | 2009-03-12 |
United States Patent
Application |
20090064884 |
Kind Code |
A1 |
Hook; Kevin J. ; et
al. |
March 12, 2009 |
Nanoparticle-based compositions compatible with jet printing and
methods therefor
Abstract
Apparatus and methods for controlling application of a substance
to a substrate involve the use of a nanoparticle-based gating agent
that blocks the substance from or attracts the substance to the
substrate. The apparatus and methods may utilize ink jet technology
to apply the gating agent directly to the substrate or to an
intermediate surface.
Inventors: |
Hook; Kevin J.; (Grand
Island, NY) ; Litman; Stanley; (Niagara Falls,
NY) ; Zaloom; Jeffrey; (Getzville, NY) |
Correspondence
Address: |
MCCRACKEN & FRANK LLP
311 S. WACKER DRIVE, SUITE 2500
CHICAGO
IL
60606
US
|
Family ID: |
39809328 |
Appl. No.: |
12/229150 |
Filed: |
August 20, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60965361 |
Aug 20, 2007 |
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60965634 |
Aug 21, 2007 |
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60965753 |
Aug 22, 2007 |
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60965861 |
Aug 23, 2007 |
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60965744 |
Aug 22, 2007 |
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60965743 |
Aug 22, 2007 |
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Current U.S.
Class: |
101/450.1 |
Current CPC
Class: |
B41M 1/06 20130101; C08K
5/17 20130101; B41M 1/10 20130101; B41J 2/0057 20130101; C09D 11/54
20130101; C09D 7/63 20180101; B41J 2/01 20130101; B41J 11/0015
20130101; C09D 7/67 20180101 |
Class at
Publication: |
101/450.1 |
International
Class: |
B41F 1/18 20060101
B41F001/18 |
Claims
1. A nanoparticle-based gating agent adapted to be applied to a
surface, the gating agent comprising: from about 5% and about 20%
of a water dispersible component; from about 5% and about 15% of an
amine; and from about 75% to about 95% of water.
2. The nanoparticle-based gating agent of claim 1, wherein the
water-dispersible component includes one of silica, alumina,
zirconia, zinc oxide, colloidal ceria, antimony oxide, and
combinations thereof.
3. The nanoparticle-based gating agent of claim 2, wherein the
water-dispersible component has size characteristics of less than
about 20 nanometers.
4. The nanoparticle-based gating agent of claim 1, wherein the
amine is an amine ethoxylate.
5. The nanoparticle-based gating agent of claim 1, wherein the HLB
is between about 2 to about 18.
6. The nanoparticle-based gating agent of claim 1, wherein the
nanoparticle-based gating agent has a pH of between about 4 to
about 6.
7. The nanoparticle-based gating agent of claim 1, wherein the
optional component is a pH modifier.
8. A device for use in a high speed variable print operation
comprising: a housing having at least one surface; a series of
ejection nozzles mounted on the one surface, each ejection nozzle
capable of ejecting a drop on demand; and a source of a gating
agent communicating with the nozzles, the gating agent comprising:
from about 8% to about 10% of a surface active agent; and the
balance of the gating agent composition comprises water.
9. The gating agent of claim 8, wherein the surface active agent
comprises a non-ionic surfactant.
10. A method for high speed variable printing comprising the steps
of: jetting a gating agent composition onto a substrate in a
pattern, the gating agent composition comprising: from about 0.05
to about 10% by weight of a blocking agent; up to about 3% by
weight of a surface tension modifying compound; up to about 8% by
weight of viscosity modifier such that the composition has a
viscosity within the range of about 1 to 14 mPa s; and the balance
of the gating agent composition comprises a solvent; wherein the
gating agent has a dynamic surface tension of less than about 60
dynes/cm; and applying a printing agent to the substrate to form a
print image in areas not covered by the pattern of the gating
agent.
11. The method of claim 10, wherein the gating agent composition is
jetted onto the substrate prior to the application of the printing
agent and the gating agent composition prevents the adherence of
the printing agent to the substrate in areas where the gating agent
has been jetted.
12. The method of claim 10, wherein the substrate is a media upon
which the print image is formed.
13. The method of claim 10, wherein the substrate is an
intermediate surface that transfers the print image to a final
print media.
14. The method of claim 10, wherein the gating agent composition is
jetted onto the substrate subsequent to the application of the
printing agent and the gating agent composition blocks the transfer
of the printing agent to a final print media in areas where the
gating agent has been jetted.
15. The method of claims 10, wherein the substrate is a print
cylinder.
16. The method of claim 10, wherein the composition has a viscosity
in the range of from about 1 to about 3 mPa s.
17. A device for use in a high speed variable print operation
comprising: a housing having at least one surface; a series of
ejection nozzles mounted on the one surface, each ejection nozzle
capable of ejecting a drop on demand; and a source of a gating
agent communicating with the nozzles, the gating agent comprising:
from about 0.05 to about 10% by weight of a blocking agent; up to
about 3% by weight of a surface modifying compound; up to about 8%
by weight of viscosity modifier such that the composition has a
viscosity within the range of about 1 to 14 mPa s; and the balance
of the gating agent composition comprises a solvent; wherein the
gating agent has a dynamic surface tension of less than about 60
dynes/cm.
18. The device of claim 17, wherein the surface modifying compound
is a nonionic surfactant having a hydrophilic-lipophilic balance
between about 11 and 30.
19. The device of claim 17, wherein the composition has a viscosity
in the range of from about 1 to about 3 mPa s.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of provisional
U.S. Patent Application Nos. 60/965,361, filed Aug. 20, 2007;
60/965,634, filed Aug. 21, 2007; 60/965,753, filed Aug. 22, 2007;
60/965,861, filed Aug. 23, 2007; 60/965,744, filed Aug. 22, 2007;
and 60/965,743, filed Aug. 22, 2007. All of the above listed
applications are hereby incorporated by reference herein in their
entireties.
BACKGROUND
[0002] Lithographic and gravure printing techniques have been
refined and improved for many years. The basic principle of
lithography includes the step of transferring ink from a surface
having both ink-receptive and ink-repellent areas. Offset printing
incorporates an intermediate transfer of the ink. For example, an
offset lithographic press may transfer ink from a plate cylinder to
a rubber blanket cylinder, and then the blanket cylinder transfers
the image to a surface (e.g., a paper web). In gravure printing, a
cylinder with engraved ink wells makes contact with a web of paper
and an electric charge may assist in the transfer of the ink onto
the paper.
[0003] Early implementations of lithographic technology utilized
reliefs of the image to be printed on the plate such that ink would
only be received by raised areas. Modern lithographic processes
take advantage of materials science principles. For example, the
image to be printed may be etched onto a hydrophilic plate such
that the plate is hydrophobic in the areas to be printed. The plate
is wetted before inking such that oil-based ink is only received by
the hydrophobic regions of the plate (i.e., the regions of the
plate that were not wetted by the dampening process).
[0004] Conventionally, all of these printing techniques have a
similar limitation in that the same image is printed over and over
again. This is due to the fact that conventional lithographic
printing uses plates wherein each plate has a static (i.e.,
unvarying) image, whether it be a relief image or an etched
hydrophobic image, etc. Gravure printing also uses a static image
which is engraved in ink wells on a cylinder. There is a
substantial overhead cost involved in making the plates that are
used by a lithographic press or cylinders/cylinder sleeves used by
a gravure press. Therefore, it is not cost effective to print a job
on a lithographic or gravure press that will have few copies
produced (i.e., a short-run job). Also, conventional lithographic
and gravure presses have not been used to print variable data
(e.g., billing statements, financial statements, targeted
advertisements, etc.) except in cases where such presses have been
retrofitted with inkjet heads, albeit at high cost and slower
speeds. Typically, short-run jobs and/or jobs that require
variability have been typically undertaken by laser (such as
electrostatic toner) and/or ink jet printers.
[0005] Traditionally, many printed articles such as books and
magazines have been printed using a process that involves a great
deal of post-press processing. For example, a single page or set of
pages of a magazine may be printed 5,000 times. Thereafter, a
second page or set of pages may be printed 5,000 times. This
process is repeated for each page or set of pages of the magazine
until all pages have been printed. Subsequently, the pages or sets
of pages are sent to post-processing for assembly and cutting into
the final articles.
[0006] This traditional workflow is time- and labor-intensive. If
variable images (i.e., images that vary from page-to-page or page
set-to-page set) could be printed at lithographic image quality and
speed, each magazine could be printed in sequential page (or page
set) order such that completed magazines would come directly off
the press. This would drastically increase the speed and reduce the
expenses of printing a magazine.
[0007] Ink jet printing technology provides printers with variable
capability. There are two main ink jet technologies: thermal, i.e.
bubble jet, piezoelectric, and continuous. In each, tiny droplets
of ink are fired (i.e., sprayed) onto a page. In a thermal jet
printer, a heat source vaporizes ink to create a bubble. The
expanding bubble causes a droplet to form, and the droplet is
ejected from the print head. Piezoelectric technology uses a piezo
crystal located at the back of an ink reservoir. Alternating
electric potentials are used to cause vibrations in the crystal.
The back and forth motion of the crystal is able to draw in enough
ink for one droplet and eject that ink onto the paper. In a
continuous ink jet system, the nozzles are continuously firing and
an electrode associated with each nozzle deflects the drops to a
gutter for collection when the nozzle is not to print. When a
nozzle is to print the electrode is deactivated and the drop will
pass to the substrate.
[0008] The quality of high speed color ink jet printing is
generally orders of magnitude lower than that of offset lithography
and gravure. Furthermore, the speed of the fastest ink jet printer
is typically much slower than a lithographic or gravure press.
Traditional ink jet printing is also plagued by the effect of
placing a water-based ink on paper. Using a water-based ink may
saturate the paper and may lead to wrinkling and cockling of the
print web, and the web may also be easily damaged by inadvertent
exposure to moisture. In order to control these phenomena, ink jet
printers use certain specialized papers or coatings. These papers
can often be much more expensive than a traditional web paper used
for commercial print.
[0009] Furthermore, when ink jet technology is used for color
printing, ink coverage and water saturation may be increased. This
is due to the four color process that is used to generate color
images. Four color processing involves laying cyan, magenta, yellow
and black (i.e., CMYK) ink in varying amounts to make a color on
the page. Thus, some portions of the page may have as many as four
layers of ink if all four colors are necessary to produce the
desired color. Additionally, the dots produced by an ink jet
printer may spread and produce a fuzzy image. Still further, inks
used in ink jet printers are extremely expensive as compared to
inks used in traditional lithography or gravure printing. This
economic factor alone makes ink jet technology unsatisfactory for
the majority of commercial printing applications, particularly long
run applications.
[0010] Laser printing has limited viability for high speed variable
printing at present, because production speeds are still much
slower than offset and gravure, and the material costs (e.g.,
toner, etc.) are extremely high compared to commercial offset or
gravure ink prices. Laser color is also difficult to use for
magazines and other bound publications, because the printed pages
often crack when they are folded.
[0011] Printing techniques have been found to be useful in the
production of other articles of manufacture, such as electrical
components, including transistors and other devices. Still further,
indicia or other markings have been printed on substrates other
than paper, such as plastic film, metal substrates, and the like.
These printing techniques may use those described above to print
paper substrates, in which case these techniques suffer from the
same disadvantages. In other cases flexography may be used, which,
like lithography, requires the prepress preparation of plates.
SUMMARY OF THE INVENTION
[0012] In one aspect of the present disclosure, a
nanoparticle-based gating agent composition includes between about
5% and about 20% of a water dispersible component, between about 5%
and about 15% of an amine, and between about 75% to about 95% of
water.
[0013] In another aspect, a device for use in a high speed variable
print operation includes a housing having at least one surface, a
series of ejection nozzles mounted on the one surface, wherein each
ejection nozzle capable of ejecting a drop on demand, and a source
of a gating agent communicating with the nozzles. The gating agent
comprises from about 8% to about 10% of a surface active agent and
the balance of the gating agent composition comprises water.
[0014] In another aspect, a method for high speed variable printing
includes the steps of jetting a gating agent composition onto a
substrate in a pattern. The gating agent composition includes from
about 0.05 to about 10% by weight of a blocking agent, up to about
3% by weight of a surface tension modifying compound, up to about
8% by weight of viscosity modifier such that the composition has a
viscosity within the range of about 1 to 14 mPa s, and the balance
of the gating agent composition comprises a solvent. The gating
agent has a dynamic surface tension of less than about 60 dynes/cm.
The method further includes the step of applying a printing agent
to the substrate to form a print image in areas not covered by the
pattern of the gating agent.
[0015] In still another aspect, a device for use in a high speed
variable print operation includes a housing having at least one
surface, a series of ejection nozzles mounted on the one surface,
wherein each ejection nozzle capable of ejecting a drop on demand,
and a source of a gating agent communicating with the nozzles. The
gating agent includes from about 0.05 to about 10% by weight of a
blocking agent, up to about 3% by weight of a surface modifying
compound, up to about 8% by weight of viscosity modifier such that
the composition has a viscosity within the range of about 1 to 14
mPa s, and the balance of the gating agent composition comprises a
solvent. The gating agent has a dynamic surface tension of less
than about 60 dynes/cm.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Further features of the apparatus and methods for
controlling application of a substance to a substrate, their
nature, and various advantages will be more apparent from the
following detailed description and the accompanying drawings, in
which:
[0017] FIG. 1 is a side view of a prior art printing system.
[0018] FIG. 2 is a side view of an illustrative embodiment of an
apparatus for controlling application of a substance to a
substrate.
[0019] FIG. 3 is a side view of an illustrative embodiment of an
apparatus for controlling application of a substance to a
substrate.
[0020] FIG. 4 is an illustration of possible output in accordance
with the apparatus shown in FIG. 3.
[0021] FIG. 5 is a schematic illustration of one embodiment of the
device of the present invention; and
[0022] FIG. 6 is a close up view of a portion of the device of FIG.
5.
DETAILED DESCRIPTION
[0023] FIG. 1 illustrates traditional offset lithographic printing
deck 100. In a traditional lithographic process, the image to be
printed is etched onto hydrophilic plate 102 to create hydrophobic
regions on the plate which will be receptive to ink. Hydrophilic
plate 102 is mounted on plate cylinder 104 and rotated through
dampening system 106 and inking system 108. Dampening system 106
may include water supply 107, and inking system 108 may include ink
source 109. The hydrophilic portions of plate 102 are wetted by
dampening system 106. By using an oil-based ink, ink is only
received by the hydrophobic portions of plate 102.
[0024] If a blanket cylinder is used, such as blanket cylinder 110,
the inked image may be transmitted from plate cylinder 104 to
blanket cylinder 110. Then, the image may be further transferred to
web 112 (e.g., paper) between blanket cylinder 110 and impression
cylinder 114. Using impression cylinder 114, the image transfer to
web 112 may be accomplished by applying substantially equal
pressure or force between the image to be printed and web 112. When
a rubber blanket is used as an intermediary between plate cylinder
104 and web 112, this process is often referred to as "offset
printing." Because plate 102 is etched and then mounted on plate
cylinder 104, a lithographic press is used to print the same image
over and over. Lithographic printing is desirable because of the
high quality that it produces. When four printing decks are mounted
in series, magazine-quality four color images can be printed.
[0025] In accordance with one aspect as depicted in FIG. 2,
apparatus and methods for controlling application of a substance to
a substrate involve the use of a nanoparticle-based gating agent
that blocks the substance from or attracts the substance to the
substrate.
[0026] Another aspect of the present disclosure is to provide a
method for high speed variable printing using a nanoparticle-based
gating agent applied transiently to the substrate. This method
includes providing a substrate and applying to the substrate a
gating agent composition capable of being jetted onto the substrate
to enable the formation of images on the substrate.
[0027] The apparatus and methods disclosed herein may utilize
jetting technology to apply the gating agent directly to the
substrate or to an intermediate surface. Any agent may be utilized
that blocks the application of ink as desired. Because the
embodiments disclosed herein comprehend the use of either (or both)
blocking and transfer-aiding compositions, or one or more
compositions that have both properties, reference will be made
hereinafter to a gating agent that may have either or both of these
capabilities with respect to a principal substance. Specifically,
the gating agent may block transfer of all, substantially all, or
some portions of the principal substance. The gating agent may
alternatively, or in addition, aid in transfer of all,
substantially all, or a portion of the principal substance, or may
block some portion(s) and aid the transfer of other portion(s) of
the principal substance. Examples of principal substances include,
for example, lithographic inks, dyes, proteins (for example,
antibodies, enzymes, prions, nucleic acids (for example, DNA and/or
RNA oligonucleotides), small molecules (for example, inorganic
and/or organic molecules), biological samples (for example, cell
and/or viral lysates and fractions thereof), pharmaceuticals
(including antibiotics and/or other drugs, and salts, precursors,
and prodrugs thereof), cells (for example, prokaryotic,
eubacterial, and/or eukaryotic cells), and metals (for example,
silicon oxides, conductive metals and oxides thereof). In FIG. 2,
the principal substance is an ink, the substrate a web of paper,
and the selective portions of the principal substance are image
areas.
[0028] FIG. 2 illustrates a printing deck 200, which may include
inking system 202, plate 204, plate cylinder 206, blanket cylinder
208, and impression cylinder 210 as known in the lithographic
printing industry. Plate 204 may be entirely hydrophilic (e.g., a
standard aluminum lithographic plate). However, dampening system
106 of FIG. 1 has been replaced with a cleaning system 212 and an
aqueous jet system 214 in FIG. 2.
[0029] Aqueous jet system 214 may contain a series of jet
cartridges (e.g., bubble jet cartridges, thermal cartridges,
piezoelectric cartridges, continuous inkjet systems, etc.). A
bubble jet may emit a drop of liquid when excited by a heater. A
piezoelectric system may eject a drop of liquid when excited by a
piezoelectric actuator. The drop is emitted from a tiny hole in the
jet cartridges. The cartridges may contain any number of holes.
Commonly, jet cartridges can be found with six hundred holes, often
arranged in two rows of three hundred. The aqueous jet units may be
known print cartridge units such as those manufactured by HP,
Lexmark, Spectra, Canon, etc. An example of a jet cartridge and jet
head is described in Murakami et al. U.S. Pat. No. 7,240,998, which
is incorporated herein by reference. Continuous systems are
available from Kodak under the trade name Versamark.
[0030] The aqueous jet system 214 or any of the jet systems as
disclosed herein may be used to emit a gating agent or a principal
substance from the ink jet cartridge(s). In one embodiment, the
gating agent and/or principal substance can include aqueous or
non-aqueous solutions. The aqueous solution may include water, a
water-soluble organic compound, or a combination thereof. One
particular embodiment uses water and a co-solvent. The co-solvent
may typically be a water soluble or miscible compound to form a
homogeneous composition. One reason to incorporate co-solvents in
the gating agents is to act as surface tension modifiers. Because
the time scale of the process is short, significant changes in
surface tension may be desirable but not obtainable using
surfactants alone. It may be desirable to have the composition have
a particular surface tension property at the time of application
and a different surface tension property at the time the image is
formed on the ultimate print surface or media. For instance, it may
be desirable to have a small amount of spreading immediately after
deposit of the composition to fill in small gaps between the jet
heads. However, the surface tension needs to immediately change at
the time the image is formed so that the edges of the image that is
formed are crisp and clean. The co-solvent can tune the surface
tension of the gating agent to a specific level. Due to the time
scale of the blocking process, relying only on the surfactant
migration to the interface may be insufficient in adjusting the
surface tension to the required level.
[0031] Suitable water-soluble or miscible organic components
include: alcohols, such as methyl alcohol, ethyl alcohol, n-propyl
alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, or
tert-butyl alcohol; amides, such as dimethylformamide or
dimethylacetamide; carboxylic acids; esters, such as ethyl acetate,
methyl lactate, ethyl lactate, propyl lactate and ethylene
carbonate; ethers, such as 2-butoxyethanol, tetrahydrofuran or
dioxane; glycerin; glycols, such as propylene glycol, and
diethylene glycol; glycol esters; glycol ethers, such as propylene
glycol methyl ether, dipropylene glycol methyl ether; ketones, such
as acetone, diacetone, or methyl ethyl ketone; lactams, such as
N-isopropyl caprolactam or N-ethyl valerolactam, 2-pyrrolidinone,
N-methylpyrrolidinone; lactones, such as butyrolactone;
organosulfides; sulfones, such as dimethylsulfone;
organosulfoxides, such as dimethyl sulfoxide or tetramethylene
sulfoxide; and derivatives thereof and mixtures thereof.
[0032] In other embodiments as disclosed herein, the gating agent
may contain a water dispersible component, such as a nanoparticle,
that is formulated to be applied to a surface. The
nanoparticle-based gating agent may be applied to any surface
including, for example, the substrate and/or plate, and/or roll
described in detail herein.
[0033] In some embodiments, the nanoparticle-based gating agent may
be silica based. In other embodiments, the nanoparticle-based
gating agent may be made from alumina, zirconia, zinc oxide,
colloidal ceria, antimony oxide or other similar materials.
Although specific nanoparticles are listed herein, other
nanoparticles may be useful that impart the desired properties to
the surface.
[0034] Suitable silica based nanoparticles that may be useful
include those supplied by Nissan Chemical (Houston, Tex.) including
Snowtex O.RTM. and/or nanoparticles supplied by Nyacol
Nanotechnologies including Nyacol Nexil 20A. The silica
nanoparticles may be supplied as spherical shaped particles, oblong
particles, and/or may be supplied in any other form.
[0035] Nanoparticles useful in the present disclosure may have
overall size characteristics of about 1 to about 10 nanometers, or
about 5 to about 15, or about 3 to about 30 or less than about 50
or less than about 100 nanometers.
[0036] Illustratively, silica based nanoparticles may have size
characteristics, wherein the silica weight percent is between about
1% to about 50% or about 5% to about 20% by weight of the silica
particles. The size of the spherical particles is between about 3
and about 100 nanometers or about 5 to about 20 nanometers. The
size of the oblong-shaped particles is between about 3 to about 50
nanometers wide and between about 50 to about 150 nanometers long
or between about 9 to about 15 nanometers wide and between about 80
and about 100 nanometers long.
[0037] Other constituents may be added to the nanoparticle before
and/or after the nanoparticle is received from the supplier. For
example, nanoparticles may include a sodium ion or other alkali ion
in a weight percent less than about 3% or less than about 1% or
less than about 0.05% or less than about 0.05%. Additional
constituents that impart desired characteristics may also be added
before and/or after the nanoparticle is received from the supplier
in any other useful weight percent.
[0038] In some embodiments, the nanoparticle may be functionalized
using an ethoxylate (EO), propoxylate (PO), and/or an
ethoxylate/propoxylate (EO/PO) moiety containing an amine. Any
amine may be used including primary, secondary, and/or tertiary
amines. For example, amine ethoxylates available from Huntsman
International LLC including the Surfonamine.RTM. series of amines
and specifically, B-60, B-30, B-200 may be useful for the present
disclosure. A typical example of the EO/PO moiety is an amine
ethoxylate that contains a single ethoxy group and nine propoxy
groups. Significant variations in the number of ethoxy and propoxy
groups may facilitate tuning the gating agent to the desired HLB
(hydrophobic-lipophilic balance) and holdout characteristics. The
HLB may be within the range of about 2 to about 18, although the
nanoparticle may be functionalized to achieve an HLB falling
outside of this range to impart desired characteristics.
[0039] In other embodiments, the nanoparticle may be functionalized
using moieties containing other functional groups. For example, a
fatty acid ethoxylate or a polyether amine may be used. Polyether
amines available from Huntsman International LLC including the
Jeffamine.RTM. series may be useful for the present disclosure.
Fatty acid ethoxylates, such as the Teric.TM. and Ecoteric.TM.
lines by Huntsman International LLC may be useful in the present
disclosure. Other functional groups may also be used to impart
desired characteristics.
[0040] Without being bound by theory, it is believed that the EO/PO
amine is electrostatically adsorbed to the surface of the silica
particle, or other suitable nanoparticle base, through protonation
to give the moiety a positive charge. The surface of the
nanoparticle is expected to have a net negative charge due to the
chemical nature of the particle surface. Additionally, the
functionalized nanoparticle has self-surfactant properties due to
the EO/PO, with tunable paper hold-out properties. Through the
modification of the silica core, or nanoparticle core with the
amine ethoxylate, it is expected that the EO/PO forms a layer or
shell structure around the core. Adjusting the size of the EO/PO
amine can impart both desired chemical and steric properties.
[0041] By way of example, the nanoparticle useful in the present
disclosure may be functionalized using the following process.
Initially, 50 g of Surfonamine.RTM. B-60 was added to a 1 L glass
beaker. 150 grams of di-ionized water was added to the beaker. The
beaker contained a magnetic stirrer, which was activated after the
di-ionized water was added to the beaker. The pH of the mixture was
measured using a standard laboratory pH meter and was found to be
about 11. The pH of the mixture was then adjusted to about 4 by
slowly adding 1.5N HCl (available from JT Baker.RTM.) to the
mixture. Using a separatory funnel (available from VWR), 50 g of
20% Nissan Snowtex-O.RTM. was added to the beaker along with 350 g
of di-ionized water. At the same time the Snowtex-O.RTM.
nanoparticles were being added to the mixture, the pH was being
monitored. Upon completion of the addition of the silica
nanoparticles, the pH was about 4. The mixture was stirred at room
temperature over night. About 100 g of acid-washed Diatomaceous
Earth was added to the mixture and stirred for about 5 minutes. The
resulting mixture was filtered using a buchner funnel using
Whatman.RTM. Grade 3 (150 mm) filter paper. The filtrate was
collected and filtered through a 1 micron absolute polyester filter
with a 0.22 nominal Versapor.RTM. membrane disc prefilter. The
resulting filtrate was collected into a Nalgene.RTM. bottle having
a 1 L capacity.
[0042] In a different embodiment, the nanoparticle may be
functionalized using larger functional groups. For example, a
polyether may be useful for the present disclosure. An ethoxylated
nonyl phenol available from Dow.RTM. under the Triton.TM. series,
for example Triton.TM. X-100, would be a typical example of a
polyether useful in the present disclosure. The nanoparticle of
this embodiment may be functionalized in a similar manner to that
described above. It is believed that unique chemical properties may
also be imparted to the gating agent by functionalizing the
nanoparticle using larger functional groups As a result of the
functionalization, the gating agent may acquire chemical properties
such as, for example, "self-surfactant", and/or "self-leveling"
properties.
[0043] In a different embodiment, the gating agent may contain a
surfactant present in an amount of up to about 15% or between about
8% to about 10%, or between about 3% and about 5%. The surfactant
or surface modifying agent may include, for example, nonionic
surfactants, such as poloxamer, ethoxylated acetylenediol or other
ethoxylated surfactants. Any type of surfactant may be useful to
include in the gating agent to impart the desired properties
including anionic, nonionic, cationic, or other types of
surfactants. In addition, leveling agents also can act as surface
modifying agents. Another class of surface modifying agents include
a multifunctional compound that contains at least one hydrophilic
portion and at least one hydrophobic/lipophobic portion (e.g.,
fluorosurfactants like Novec from 3M). This class of compounds
enables the jetting of a water soluble blocking agent onto a
substrate that has a lipophilic portion tending to repel the
lithographic ink.
[0044] Further suitable nonionic surfactants include secondary
ethoxylated alcohols such as the Tergitol series, for example,
15-S, available from Dow Chemical, C1-C15 linear ethoxylated
alcohols, ocyylphenol ethoxylates, ethoxylated acetylenic diols,
and N-octyle-2-pyrrolidone. As noted above, mixtures of various
nonionic surfactants can also be used to provide a combined
surfactant effect with an HLB of between about 2 to about 18.
[0045] The poloxamer surfactant suitable for use can be represented
by the formula
HO(CH.sub.2CH.sub.2O).sub.x(CH.sub.2CHCH.sub.3O).sub.y(CH.sub.2CH-
.sub.2O).sub.zH wherein x, y and z represent integers from the
range from 2 to 130, especially from 15 to 100, and x and z are
identical but chosen independently of y. Among these, there can be
used poloxamer 188 wherein x=75, y=30 and z=75, which is obtainable
under the trade name Lutrol.RTM. F 68 (alternatively Pluoronic.RTM.
F 68) from BASF, poloxamer 185 wherein x=19, y=30 and z=19
(Lubrajel.RTM. WA from ISP), poloxamer 235 wherein x=27, y=39 and
z=27 (Pluoronic.RTM. F 85 from BASF), poloxamer 238 wherein x=97,
y=39 and z=97 (Pluoronic.RTM. F 88 from BASF), Pluoronic.RTM. 123
from BASF, and/or Pluoronic.RTM. 127, poloxamer 407, from BASF for
which x=106, y=70, and z=106. Additionally, poloxamer 101, 108,
124, 181, 182, 184, 217, 231, 234, 237, 282, 288, 331, 333, 334,
335, 338, 401, 402, and 403, respectively can be included in the
gating agent, to name a few.
[0046] The ethoxylated acetylenediol suitable for use include Air
Products' Surfynol.RTM. 400 series surfactants: Surfynol.RTM. 420,
440, 465, and 485, respectively. The Surfynol.RTM. 400 series
surfactants are produced by reacting various amounts of ethylene
oxide with 2,4,7,9-tetra-methyl-5-decyne-4,7-diol (Air Products'
Surfynol.RTM. 104), a nonionic molecule with a hydrophilic section
in the middle of two symmetric hydrophobic groups. A further
suitable surfactant includes SILWET.TM. 7200, a siloxane block
polymer, available from OSi Specialties, Inc. (Danbury, Conn.,
formerly Union Carbide Organo Silicon Products, Systems and
Services). Another suitable gating agent component is BASF's
Sokalan.RTM., maleic acid/olefin copolymer. Other useful materials
may include polyethyleneimine (PEI) having a molecular weight of
around 1200, ethoxylated PEI having a molecular weight around
50,000, hexadecyl trimethylammonium bromide (CTAB), polyoxyalkylene
ether, poly(oxyethylene)cetyl ether (e.g., Brij.RTM. 56 or
Brij.RTM. 58 from Atlas Chemicals).
[0047] The surfactant may be reacted with a sterically large amine
including aromatic amines, to form an organic salt that can be used
in a dilute concentration. Amines useful in the present disclosure
may include dicyclohexyl amine, cyclohexyl amine, and/or butyl
amines.
[0048] In some embodiments, if necessary, the gating agent
composition may also include a viscosity modifying agent to achieve
a viscosity within the range of 1 to 14 mPa s. More preferably, the
viscosity is set to 1 to 8 mPa s, and most preferably to 1 to 4
mPas. The viscosity agent may include polyethylene glycol,
propylene glycol, cellulosic materials (e.g. CMC), xanthan gum, or
Joncryl.RTM. 60, Joncryl.RTM. 52, Joncryl.RTM. 61, Joncryl.RTM.
678, Joncryl.RTM. 682 solution polymers from BASF,
polyvinylpyrrolidone, such as PVP K-12 to K-90 available from
International Specialty products, Wayne, N.J. and polyglycol 15-200
to name a few.
[0049] In some embodiments, the gating agent includes from about
0.05 to about 10% of a blocking compound. Examples of suitable
blocking compounds include polyvinylmethylene/maleic acid
copolymers such as Gantrez S-96-BF and Gantrez AN-119, both
available from International Specialty Products, Wayne, N.J.,
glycerin, 1,2,3,4 butane tetra carboxylic acid, silicone polyols,
such as GP217 polymer, Cationic silicone polyols, such as quaterium
8; sulfonated polyesters such as AQ 48 Ultrapolymer, and mixtures
thereof.
[0050] In other embodiments, the surface tension modifier is used
to reduce spreading. Preferably, dynamic surface tension is set to
less than 60 dynes/cm. More preferably, a dynamic surface tension
of less than 46 dynes/cm is attained. The surface tension modifier
may include poloxamer (e.g., BASF's Pluronic.RTM.) or Air Products'
Surfynols.RTM. (e.g. Surfynol.RTM. 400 series surfactants),
leveling agents such as BYX-381, BYK-333 and BYK-380N,
polydimethylsiloxanes that are manufactured by BYK-Chemie USA,
Wallingford, Conn. among others.
[0051] In yet other embodiments, the gating agent composition
includes a receiving surface modifier. The receiving surface (e.g.
paper) modifier facilitates the transfer of blocked ink or other
principal substance to the receiving surface. The receiving surface
modifier may include surface dusting powders such as metal powders,
and cork powder, to name a few. Other examples of surface modifying
compounds include polyethyleneimine and ethoxylated
polyethyleneimine (10 to 80% ethoxylation).
[0052] Additional contemplated components in the gating agent
include a solvent, a preservative, an anticurl agent, a gating
agent anchor, a humectant (e.g. propylene glycol), an antiseptic
agent, a biocide, a colorant, a scent, a surfactant, a polymer, a
defoaming agent, a leveling agent, a salt, an inorganic compound,
an organic compound, water, a pH modifier, and/or any combination
thereof.
[0053] The aqueous jet system 214 may be used to "print" or jet the
positive image (or a negative image) of the image to be printed, or
any portion thereof, on plate cylinder 206. For example, an image
controller may receive image data from a data system. The image
data may represent the image to be printed or the negative image to
be printed. The image data may include variable image data that
changes relatively frequently (e.g., every printed page),
semi-fixed image data that changes less frequently (e.g., every 100
printed pages), fixed image data that remains static, and any
combination of variable, semi-fixed, and fixed image data. Some or
all of the image data may be stored as binary data, bitmap data,
page description code, or a combination of binary data, bitmap
data, and page description code. For example, a page description
language (PDL), such as PostScript or Printer Command Language
(PCL), may be used to define and interpret image data in some
embodiments. The data system may then electronically control
aqueous jet system 214 to print in aqueous solution the image (or
the negative image) represented by some or all of the different
types of image data (or any portion thereof) onto plate cylinder
206. The negative image may be an image of every portion of the
paper that is not to receive ink. Thus, after a point on plate
cylinder 206 passes aqueous jet system 214, that point will only
receive ink from inking system 202 if a drop of aqueous solution
was not placed at that point. In some embodiments, a vacuum source
or heat source 215 may be positioned next to or near aqueous jet
system 214. As plate cylinder 206 completes its revolution, after
passing the image to blanket cylinder 208, it passes through
cleaning system 212, which may remove ink and/or aqueous solution
residue so that plate cylinder 206 may be re-imaged by aqueous jet
system 214 during the next revolution (or after a certain number of
revolutions).
[0054] In some embodiments, plate cylinder 206 may have all of the
static data for a particular print job etched onto plate 204 by
traditional lithographic techniques. Aqueous jet system 214 may
then be used to image only variable portions of the job represented
by the variable or semi-fixed image data on specified portions of
plate 204. In other embodiments, plate 204 may not be used.
Instead, as is understood in the art, the surface of plate cylinder
206 may be treated, processed, or milled to receive the aqueous
solution from aqueous jet system 214. Additionally, plate cylinder
206 may be treated, processed, or milled to contain the static data
and be receptive to the aqueous solution to incorporate variable
data. In these and any other embodiments herein, blanket cylinder
208 may be eliminated entirely, if desired, by transferring the
image directly to web 216.
[0055] As described above, the gating agent may be applied using
one or more jet heads either to a plate or directly to a blanket
cylinder, then ink may be applied in a non-selective fashion to the
plate or blanket cylinder, and then the ink may be transferred from
the image areas on the plate or blanket cylinder to the web of
paper. In the event that the gating agent and the ink are applied
directly to the blanket cylinder, the plate cylinder need not be
used. Particular printing applications that may benefit include
static print jobs (particularly, but not limited to, short runs),
or variable or customizable print jobs of any size, for example,
targeted mailings, customer statements, wallpaper, customized
wrapping paper, or the like.
[0056] The gating agent may be applied as, for example, an aqueous
fluid by being selectively sprayed directly onto the substrate or
onto an intermediate surface or directly onto the principal
substance using a jet device or other precisely controllable
spraying or application technology. An aqueous fluid may generally
have a low viscosity and a reduced propensity to form clogs, and is
therefore advantageous for use with an jet head. However, the
gating agent may also be applied using jet technology in a form
other than an aqueous fluid. Examples include UV curable systems
and non aqueous siloxane systems Further, the gating agent is not
limited to being a fluid at all and may be applied as a solid, for
example as a thin film, a paste, a gel, a foam, or a matrix. The
gating agent could comprise a powdered solid that is charged or
held in place by an opposite electrostatic charge to prevent or aid
in the application of the principal substance.
[0057] Any of the systems described herein may be modified to allow
formation of different drop sizes of gating agent. In general, a
higher resolution grid, that is a grid with 300 dpi or greater,
along with matched drop size improves blocking or
transfer/collection of the principal substance, such as an ink.
Also, as the dpi of the grid increases, the size of the drops that
are most efficacious general are smaller. A larger drop size is
more susceptible to forced wetting of areas to be imaged. This
forced wetting can result from merging of adjacent jetted drops
when the image is transferred between surfaces (such as in the nip
area between a plate and blanket) and can cause a decrease in image
quality due to a reduction in print density. Such forced wetting
can be minimized by the addition/removal of one or more
constituents and/or changing or adjusting one or more physical
properties of the gating agent. For example, reducing certain
surfactants may reduce ghosting while utilizing, adding, and/or
substituting other surfactants may also improve image quality.
Alternatively, one could apply an electrostatic charge to a
cylinder that is opposite in the polarity to the charge of the
gating agent applied to the cylinder. The resulting electrostatic
attraction may reduce or eliminate forced wetting.
[0058] The gating agent may be used to accomplish blocking or
aiding the application of the principal substance by removing or
blocking or applying the principal substance in image or non-image
areas, removing an aiding agent in non-image areas, preventing the
application of the principal substance in certain or all areas,
changing the physical or chemical properties of the gating agent or
principal substance (such as changing the viscosity or surface
tension of the gating agent or principal substance) to affect the
application of the gating agent or principal substance, any
combination of the foregoing, or by any other suitable method.
[0059] In yet other embodiments, the amount of the principal
substance applied to the substrate may vary through use of a gating
agent in the form of a barrier or a blocking agent with barrier
qualities. In such embodiments, the application of the principal
substance to the substrate may be blocked either completely or
partially, so that the principal substance may be applied in
intermediate levels to the substrate, as the barrier or the
blocking agent with barrier qualities allows, effectuating a
density gradient of the principal substance on the substrate in
accordance with desired intermediate levels of principal substance
application.
[0060] Further embodiments include the blocking agent being applied
selectively to the principal substance on the surface or other
substrate, before or after application of the principal substance
to the surface. For example, the blocking agent may include a
material dispersed within it that is resistant to affinity with the
particular embodiment of the principal substance used. The blocking
agent may then be applied to the surface in non-image areas, with
the material dispersed within the blocking agent absorbed into
and/or received and retained on the surface. The surface may then
be passed adjacent a further surface having the principal substance
disposed thereon, and the principal substance may be transferred to
the first-named surface only in those areas which do not contain
the blocking agent, as the material dispersed within the blocking
agent resists the application of the principal substance to the
non-image areas.
[0061] Properties of the gating agent and of the print medium
(e.g., using bond paper, gloss paper, or various coating
techniques) may be varied to achieve a desirable interaction
between the protective negative image that is printed with the
aqueous jet system and the print medium. For example, if image
sharpness is desired, it may be beneficial to choose a gating agent
that will not be absorbed at all by the print medium. However, if
some transfer of ink is desirable even from the areas covered with
the output of the aqueous jet system, it may be beneficial to use a
print medium that quickly absorbs the aqueous solution so that some
ink transfer is also able to occur from the covered areas. Still
further, increasing the viscosity of the gating agent and/or
increasing the surface tension thereof, and/or using a supporting
agent and/or system for non-image and image areas, respectively,
such that the boundaries between image and non-image areas are
maintained can reduce spreading, thus improving quality. In
particular, manipulating the viscosity of the gating agent to 1 to
14 cP (or mPas) prevents flooding, that is forced wetting that
loses the image, including ragged edges and lines, as well as
minimizes ghosting, Ghosting may occur when ink migrates to a
non-image area of a cylinder or when residual ink or gating agent
remains on a cylinder from a prior impression. It is important that
the viscosity of the gating agent be maintained at a value less
than 14 cP (or mPas) to allow for the gating agent to be emitted
from a thermal jet head. Other chemical and/or materials science
properties might be utilized to reduce or eliminate this effect.
The gating agent may also include a thixotropic fluid that changes
viscosity under pressure or agitation. Manipulating the surface
tension of the gating agent can also reduce spreading.
[0062] Still further, surfactant block copolymers having various
properties may be used with imaging cylinders having various
material properties to achieve an imaging cylinder that has a
selectively oleophilic and hydrophilic surface. The physical bond
created between the surfactant and the imaging cylinder's surface
allows the imaging cylinder to repeat the same image multiple times
or to selectively vary the image in any given rotation of the
imaging cylinder. By taking advantage of the material properties of
the imaging cylinder and the block copolymer surfactants, a
durable, yet variable, imaging system having the quality of known
lithographic printing techniques may be achieved.
[0063] Another process variable is the substrate itself. In the
case of a paper substrate, a conventional coated stock of
appropriate size, weight, brightness, etc. may be used. One or more
coatings, such as clay, may be applied thereto to delay/prevent
absorption of principal substance and/or gating agent. In the case
of other substrates, such as a printing blanket, a printing plate,
a printing cylinder, a circuit board, a plastic sheet, a film, a
textile or other sheet, a planar or curved surface of a wall, or
other member, etc., the surface to which the principal substance is
to be applied may be suitably prepared, processed, treated,
machined, textured, or otherwise modified, if necessary or
desirable, to aid in and/or block transfer of portions of the
principal substance, as desired.
[0064] The types and/or physical characteristics and/or chemical
compositions of the ink(s) or other principal substance(s) may be
selected or modified to obtain desired results. For example, by
controlling the surface tension of the ink, color-to-color bleed
and showthrough on the opposite side of the paper can be
eliminated. As a further example, one or more ink(s) used in
waterless printing applications may be employed together with
jetted gating agent (whether the latter is aqueous or non-aqueous)
to block or promote transfer of ink from plate to paper. In the
case of the use of waterless printing ink(s) with an aqueous gating
agent, the composition of the gating agent may be adjusted in view
of the lipophilic characteristics of such ink(s) so that the gating
agent has a molecular structure that attracts and/or repels the
ink(s) as necessary or desirable. Alternatively, jetted gating
agent applied initially to a hydrophilic plate may include one or
more hydrophilic components that bond with the plate and one or
more other components that bond with or repel ink molecules.
[0065] As a still further example, a phase change of the gating
agent, or the principal substance, or both, may be employed to
prevent and/or promote substance blocking or transfer/collection.
For example, gating agent may be selectively jetted onto a surface,
such as a plate, and principal substance may be applied to the
surface having the gating agent applied thereto, whereupon the
portions of the principal substance that contact the jetted gating
agent may be converted to a gel or a solid. Alternatively, the
principal substance may be applied in an indiscriminate (i.e.,
non-selective) fashion to the plate and the gating agent may
thereafter be selectively applied to portions of the plate that are
not to be imaged (i.e., non-image areas), whereupon the principal
substance in the jetted portions is converted to a gel or solid.
Still further, a two (or more) component gating solution could be
used wherein the components are individually selectively applied in
succession where each is individually jettable, but which, when
applied in the same location, react similarly or identically to an
epoxy-type and other chemical bonds such as covalent, ionic
bonding, etc., and physical interactions such as hydrogen bonding,
Van der Waals forces to promote advantageous gating
characteristics. The principal substance, such as ink may be
applied before or after one or more of the gating agent components
are applied. In any of the foregoing examples, a substrate (such as
a web of paper) may be imaged by the plate.
[0066] FIG. 3 illustrates another alternative embodiment. FIG. 3
shows lithographic deck 1000 as known in the art (e.g., inking
system 1002, plate cylinder 1006, blanket cylinder 1008, and
impression cylinder 1010). However, upstream from lithographic deck
1000, coating system 1016 and aqueous jet system 1014 have been
installed. In embodiments like that shown in FIG. 3, a standard
lithographic plate may be etched with the static information for a
given job or may be completely ink receptive. In one embodiment, a
portion of the plate may be reserved for variable information
(e.g., plate 1100 may include one or more variable image boxes,
such as boxes 1102 and 1104, as shown in FIG. 4). The portion of
the lithographic plate that corresponds to the variable image boxes
may be formed to be ink receptive over the entire surface of the
variable image boxes (i.e., when the variable image box portions of
the lithographic plate passes the inking system, the entire
rectangular areas will accept ink). In other embodiments, the
entire plate may be receptive to ink and the aqueous jet system can
provide blocking fluid across the entire web 1012.
[0067] To generate the variable image, a negative image of the
variable image may be applied in gating agent by aqueous jet system
1014 directly onto web 1012. Before web 1012 reaches aqueous jet
system 1014, web 1012 may be in some embodiments, be coated to
prevent web 1012 from absorbing the gating agent. In other
embodiments, the web 1012 remains uncoated so that the gating agent
applied by the aqueous jet system 1014 can apply the image to the
entire web 1012. Thus, when the portion of web 1012 to receive the
variable image makes contact with the portion of blanket cylinder
1008 transferring the ink for the variable image, web 1012
selectively receives the ink only in the areas not previously
printed on by aqueous jet system 1014. The standard lithographic
deck operates as though it is printing the same image repeatedly
(e.g., a solid rectangle). However, web 1012, which is first
negatively imaged by aqueous jet system 1014, only selectively
receives the ink in the solid rectangle on blanket cylinder 1008 to
create the variable image on web 1012. Coating system 1016 may be
an entire deck of its own for applying the coating. Alternatively,
coating system 1016 may be any suitable alternative for applying a
coating to web 1012 to reduce its ability to absorb the gating
agent. For example, coating system 1016 may include a sprayer that
sprays a suitable solution onto web 1012. The solution may prevent
web 1012 from absorbing all or some of the gating agent.
[0068] In any of the foregoing embodiments, a blanket and plate
cylinder combination may be replaced by a single imaging cylinder
and vice versa. Further, one or more of the aqueous jet systems,
cleaning systems, stripping systems, and vacuum or heating systems
in embodiments may be electronically controlled via data
system.
[0069] Still further, the nip pressure of the roller(s) and the
compressibility characteristic of the roller(s) at which the
principal substance is applied to the substrate may be varied to
control image quality as well as the compressibility characteristic
of the nip roller. Also, rolls or cylinders having a textured
surface may be used to control the application of the principal
substance to the substrate, as desired. Still further, or in
addition, the volume of the drops of gating fluid could be adjusted
to control the amount of ink transferred into each cell, thereby
affecting grayscale.
[0070] A still further option is to modulate/control the
temperature of one or more process parameters. For example, one
might elevate the temperature of the gating agent upon application
thereof to a surface to improve adherence and facilitate dispensing
thereof. Alternatively, or in addition, the surface may initially
be heated during application of gating agent to control adhesion,
drop shape/size, and the like, and/or the surface may be chilled at
some point in the process once the gating agent is applied thereto
so that the viscosity of the gating agent is increased, thereby
reducing spread of the gating agent into non-wetted areas.
[0071] One could further use multiple different liquids dispensed
by separate jet devices that, when applied together, create a
gating agent that has improved adherence and/or viscosity and/or
other desirable characteristic. The liquids may be applied at the
different or same temperatures, pressures, flow rates, etc.
[0072] Yet another embodiment comprehends the use of two or more
arrays or ink jet heads for selectively applying gating agent
alone, or for selectively applying gating solution to one or more
areas of a surface and, optionally, ink to one or more remaining
areas of the surface, wherein one or more of the arrays can be
independently removed and switched over while the press is running,
or, reconfigured (in terms of position) for the next succeeding job
(e.g., where regional customization is required).
[0073] Due to variations in ink tack from print unit to print unit,
one may undertake a successive modification of gating agent
characteristics from unit to unit to effectively optimize ink
transfer by each unit. Yet another modification involves the use of
a phase change material to build up a printing surface.
[0074] In yet other embodiments, the gating agent(s) used to
control application of the principal substance to the substrate may
be combinations of blocking and aiding agents. In one example, the
principal substance is disposed on a surface and is covered in
non-image areas by a blocking agent that blocks application of the
principal substance to the substrate. In image areas, the principal
substance is covered by an aiding agent that tends to establish a
bond with the principal substance to aid in application onto the
substrate. Alternately, the gating agent(s) may be disposed on the
surface and covered by the principal substance. In one example, a
lipophilic blocking agent is selectively disposed on non-image
areas of the surface and a hydrophilic aiding agent is selectively
disposed on image areas of the surface. The principal substance is
then disposed on top of the layer created by both gating agents.
The layer of both gating agents having a consistent height on the
first surface may prevent migration between the principal substance
and the aiding agent. As the surface is moved adjacent the
substrate, the blocking agent keeps the principal substance from
being applied to the substrate, while the aiding agent allows
application of the principal substance to the substrate.
[0075] In alternate embodiments, the surface may be a lithographic
plate, cylinder, or the like having a portion that may be used for
controlling application of the principal substance to the substrate
by applying variable configurations of the principal substance to
the substrate. In such embodiments, variable symbology, encoding,
addressing, numbering, or any other variable tagging technique may
be utilized in the portion of the first surface reserved for
controlling application of the principal substance. The principal
substance is first disposed on the first surface indiscriminately.
Before the substrate is passed near the first surface for
application of the principal substance, a blocking agent is
selectively applied to the substrate in an area where the reserved
portion of the first surface will subsequently be moved adjacent
the substrate so as to allow the desired configuration, or image,
of the principal substance to be applied thereto. In a more general
embodiment, the substrate may be brought adjacent one or more than
one surface having similar or differing principal substances
disposed thereon, wherein blocking and/or aiding agents are
selectively transferred to the substrate from the surfaces in the
reserved portion. In one embodiment, a magnetic ink is transferred
from one of these surfaces to the substrate (e.g., a paper web).
One or more non-magnetic inks may be transferred from the same
surface or from one or more additional surfaces. A gating agent may
be used to either block or aid application of the magnetic ink to
the paper web in a desired configuration in the reserved portion
thereof using any of the techniques for using blocking and aiding
agents described above. The result is a printed paper web having
markings of magnetic ink (such as a MICR marking or other encoded
information) that may be changed from impression-to-impression.
Another example is applying encoded RFID circuits as part of the
variable print process through the use of a conductive ink. This
eliminates the need for post printing programming.
[0076] According to a still further embodiment, the gating agent is
selectively applied to a receiver surface by one or more jet heads
and attracts or blocks an intermediate fluid, such as traditional
fountain solution, which is applied indiscriminately to the
receiver surface but gated by the gating agent, such that the
fountain solution adheres selectively to the receiver surface prior
to application of ink thereto. In this embodiment, the gating
solution is formulated to interact with and control the fountain
solution, as opposed to controlling the ink. Additional embodiments
may neutralize or compromise the fountain solution, or selectively
enable removal thereof from the receiver surface. In more general
terms, these embodiments comprehend the use of a selectively
applied gating solution together with indiscriminately applied
fountain solution and ink wherein the gating agent controls where
the fountain solution is maintained.
[0077] As mentioned above, the gating agent may include one or more
surfactants or may be temperature or vacuum controlled to produce
drop size and viscosity characteristics that are favorable to
produce a high quality image. However, the quality of an image may
also be affected by a phenomenon known to those of skill in the art
as ghosting, which may be an especially serious problem if
consecutive images are different.
[0078] Ghosting may be diminished by assuring that the image and
non-image areas are clean of ink and/or any gating agents between
successive impressions. Cleaning the cylinder after every
application of ink therefrom as described with respect to any of
the cleaning systems discussed hereinabove is one way to assure
that the cylinder is clean. The composition of the gating agent may
also be engineered to reduce ghosting by promoting more complete
cleaning by the cleaning system.
[0079] Another approach to diminish ghosting is to inhibit the
migration of ink from the image areas to the non-image areas on the
cylinder. A lipophilic solution may be precisely applied to the
image areas to attract ink thereto and inhibit migration therefrom.
Independently, or in combination with the lipophilic solution, a
lipophobic solution may be precisely applied to the non-image areas
of the cylinder to inhibit migration of ink thereto.
[0080] One of the advantages of using the concepts for processing
variables and static print jobs as have been described herein is
the inherent speed associated with a conventional lithographic
press. In fact, press speed compared to a conventional lithographic
press is limited by the speed at which an image area can be
created, which in turn depends upon the method of creation of the
image area. Such methods have been described herein to include
application of a gating agent to create the image area. The gating
agent may be a lipophilic or hydrophilic solution, or some other
solution that may have an electrostatic charge applied thereto. The
gating agent may also be an electrostatic charge applied to a
portion of a cylinder. The maximum speed at which any of these
gating agents is applied to one or more cylinders of the press may
limit the speed of operation of the press.
[0081] For most operating conditions wherein an ink jet cartridge
is utilized in normal ink jet printing, the ejection of a droplet
from the cartridge is considered to be an instantaneous event that
produces a spot of ink of predetermined size on a target substrate.
In reality, the ejection of a droplet from an ink jet cartridge is
not an instantaneous event, but is in fact a transient event,
having a beginning, a middle, and an end. If a target substrate is
moving at a high speed, the ink droplet may strike the substrate to
form a spot of ink having a tail trailing the spot in a direction
opposite to the direction of travel of the substrate. This
phenomenon, known as tailing, is a direct result of the transient
nature of the droplet generation. Tailing at high press speeds may
limit the effective speed of the press due to print quality
concerns. It has been found, however, that certain gating agents,
when used with particular jet cartridges may inhibit or alleviate
the tailing of the ejected droplets, thereby removing this effect
as a limiting factor on maximum press speed.
[0082] In another embodiment, an aqueous jet system may print or
jet an aqueous solution or other composition that has a
multifunctional potential onto a pattern substrate. In one
embodiment, for example, the composition may have a bifunctional
potential, though any number of functionalities are contemplated
herein. For example, the multifunctional composition may include
one or more compounds each having a multifunctional potential or a
plurality of compounds each having monofunctional potentials. A
functional potential may include, for example, a function portion
of a compound that may be attributable to a specific chemical
moiety and/or structural region of the compound that confers
attachment and/or repellant properties to the compound, such as,
for example, a hydrophilic region, a lipophilic region, a
receptor/recognition region (for example, a paratope), an ionic
region, and others known in the art. In the present embodiment, one
functionality confers attachment capabilities to the pattern
substrate, and a second confers attachment properties to one or
more principal substances that may be applied thereto.
[0083] In another embodiment, a multifunctional composition may
include more than one multifunctional compound where each species
of multifunctional compound has at least one functionality in
common with the other multifunctional compounds and at least one
functionality that differs from the other multifunctional
compounds. In this example, a first multifunctional compound and a
second multifunctional compound may each be printed onto a similar
pattern substrate though the second functionalities of the first
multifunctional compound and the second multifunctional compounds
may have different specificities for a principal substance that can
be attached to either the first or the second multifunctional
compound, assuming the principal substance only reacts with one
type of functionality. In another embodiment, compounds having
monofunctional potentials may interact to form complexes having
multifunctionality similar to that of single multifunctional
compounds. In this embodiment, the monofunctional compounds may be
included in a single composition that is deposited on the pattern
substrate at one time, included in separate compositions deposited
simultaneously, or may be contained in separate compositions that
are deposited on the pattern substrate sequentially.
[0084] One example of a multifunctional compound contemplated
herein includes a compound having one functionality that may be
hydrophilic and a second functionality that may be lipophilic. The
multifunctional composition may be jetted using in a desired
pattern onto a substrate having either hydrophilic or a lipophilic
surface, whereby like functionalities amongst the surface and the
composition would associate to attach the composition to the
surface and the opposite functionality of the composition would be
repelled from the surface to render a pattern of the composition
attached thereon.
[0085] A second composition, for example, the principal substance,
having a like functionality (for example, hydrophilic or
lipophilic) or otherwise attracted selectively to the second
functionality of the multifunctional composition, which is not
attached to the surface, and that is repulsed from or otherwise not
attachable to the exposed surface of the substrate may be added to
the surface by jetting, dipping, spraying, brushing, rolling, or
any other manner known to a skilled artisan. Addition of the
principal substance may render a pattern of the principal substance
corresponding to that of the multifunctional composition, such that
the principal substance is only attached to the surface via the
second functionality of the multifunctional composition. It is
further contemplated that after the application of the principal
substance, one or more additional steps may be performed,
including, for example a cleaning step, to ensure regiospecific
attachment of the principal substance only to the second
functionality of the multifunctional composition. Another
contemplated step similar to the cleaning step includes a
sterilization step. The principal substance may then be transferred
to a second substrate, including, for example, an intermediate
roller from which an image will be transferred to the print medium,
or directly to the print medium to render the desired print image
in a highly accurate and clean manner. In this way, selected
patterns may be jetted onto a substrate using a multifunctional
composition to which a principal substance is subsequently attached
that then may be transferred to and immobilized permanently or
transiently on a print medium.
[0086] Examples of multifunctional compounds contemplated herein
include polymers, having at least one hydrophilic portion and at
least one lipophilic portion, such as a poloxamer or acetylenediol
ethoxylated mentioned above. Additional examples include materials
associated with the formation of self-assembled monolayers, such as
alkylsiloxanes, fatty acids on oxidic materials, alkanethiolates,
alkyl carboxylates, and the like. Other multifunctional compounds
known to one skilled in the art are contemplated in the present
disclosure.
[0087] The apparatus and methods disclosed herein are also relevant
in other industries and other technologies, for example, textiles,
pharmaceuticals, biomedical, and electronics, among others.
Variably customizable graphics or text, or a principal substance
having enhanced sealing properties or water or fire resistance may
be selectively applied to webs of textiles such as may be used to
manufacture clothing or rugs. In the pharmaceutical industry, the
principal substance may be a drug, a therapeutic, diagnostic, or
marking substance other than an ink, or a carrier for any other
type of substance. In biomedical applications, for example, the
principal substance may be a biological material or a biocompatible
polymer. In electronics applications, the principal substance may
be an electrically conductive or insulative material that may be
selectively applied in one or more layers on the substrate. Other
electronic applications include production of radio frequency
identification ("RFID") tags on articles. Other industries may also
benefit from selective application of a principal substance to a
substrate. For example, the principal substance may be a thermally
conductive or insulative material selectively applied over
components of an item of manufacture, for example, a heat
exchanger, a cooking pan, or an insulated coffee mug. The principal
substance may also be a material with enhanced absorptive,
reflective, or radiative properties, some or all of which may be
useful in other items of manufacture, for example, when the
principal substance is selectively applied to components of an
oven, a lamp, or sunglasses. Still further uses for the principal
substance may include customizable packaging films or holograms
(via selective filling of refractive wells prior to image forming).
Moreover, the technology could be applied to fuel cell
manufacturing and the principal substance may include functional
polymers, adhesives and 3-D interconnect structures. In
applications for the manufacture of micro-optical elements, the
principal substance could be an optical adhesive or a UV-curing
polymer. Yet a further application may be display manufacturing
wherein the principal substance is a polymer light-emitting diode
material. Further, in a specific application, the apparatus and
high speed variable printing methods disclosed herein may be used
in a number of lithographic applications. For example, the
disclosed apparatus and methods may be ideal for high-quality
one-to-one marketing applications, such as direct mailing,
advertisements, statements, and bills. Other applications are also
well-suited to the systems and methods disclosed herein, including
the production of personalized books, periodicals, publications,
posters, and displays. The high speed variable printing systems and
methods disclosed herein may also facilitate post-processing (e.g.,
binding and finishing) of any of the aforementioned products.
[0088] Referring to FIGS. 5 and 6, the gating agent may be jetted
using a device 1200. The device 1200 has a housing 1202 with a
surface 1204. The surface 1204 has a plurality of jet nozzles 1206
and 1208. In FIGS. 5 and 6, two rows of nozzles 1206 and 1208 are
shown however, the device can have one or more rows of nozzles
depending on the needed resolution. The housing 1202 includes a
chamber (not shown) in communication with the nozzles and also in
communication with a source of jetting agent 1210 via a tube or
other communication media 1212 The device 1200 is controlled by a
control device 1214 that may be any suitable print controller well
known to this skilled in the art.
[0089] The following examples further illustrate the disclosure
but, of course, should not be construed as in any way limiting its
scope.
EXAMPLE 1
[0090] A nanoparticle-based blocking gating agent formulation
useful in the present disclosure was prepared as follows:
TABLE-US-00001 7.11 wt % Huntsman B-60 7.11 wt % Snowtex-O .RTM.
from Nissan Chemicals 0.43 wt % Hydrochloric Acid from JT Baker
85.35 wt % DI water
EXAMPLE 2
[0091] A second blocking gating agent formulation useful in the
present disclosure was prepared as follows:
TABLE-US-00002 3.8 wt % Polyvinyl Pyrrolidone (K12) 4.8 wt %
Polyoxyethylene(12) Tridecyl Ether 91.3 wt % DI Water
EXAMPLE 3
[0092] A third blocking gating agent formulation useful in the
present disclosure was prepared as follows:
TABLE-US-00003 10 wt % Polyoxyethylene(12) Tridecyl Ether 90 wt %
DI Water
EXAMPLE 4
[0093] A fourth blocking gating agent useful in the present
invention was prepared as follows:
TABLE-US-00004 72.5 wt % deionized water 10 wt % GP 217 (Genesee
Polymer - silicone modified polymer) 2.5 wt % BKY 333 15 wt %
N-methyl-2-pyrrolidone
EXAMPLE 5
[0094] A fifth blocking gating agent useful in the present
invention was prepared as follows:
TABLE-US-00005 92.42 wt % deionized water 4.74 wt % quaterium 8
(SilSense Q-plus) 0.94 wt % Surfynol .RTM. 485 0.2 wt % Surfynol
.RTM. 440
EXAMPLE 6
[0095] A sixth nanoparticle-based blocking gating agent formulation
useful in the present disclosure was prepared as follows:
TABLE-US-00006 3.55 wt % Huntsman B-60 7.11 wt % Snowtex-O .RTM.
from Nissan Chemicals .43 wt % Hydrochloric Acid from JT Baker
88.91 wt % DI water
EXAMPLE 7
[0096] A seventh nanoparticle-based blocking gating agent
formulation useful in the present disclosure was prepared as
follows:
TABLE-US-00007 7.11 wt % Huntsman B-60 14.22 wt % Snowtex-O .RTM.
from Nissan Chemicals 0.43 wt % Hydrochloric Acid from JT Baker
78.24 wt % DI water
[0097] All of the formulations of Examples 1-7 were useful as
blocking or gating agents and produced valuable print with a
minimum of ghosting, tailing, flooding, or background color.
[0098] It will be understood that the foregoing is only
illustrative of the principles of the systems and methods disclosed
herein, and that various modifications can be made by those skilled
in the art without departing from the scope and spirit of such
systems and methods. For example, the order of some steps in the
procedures that have been described are not critical and can be
changed if desired. Also, various steps may be performed by various
techniques. In addition, one advantage of the compositions and
methods described is the use of standard lithographic inks to
produce variable images. These inks typically produce higher
quality publications than can be produced using ink jet inks. Until
this technology, it was very difficult to produce true variable
lithographic printing.
[0099] Preferred embodiments of this disclosure are described
herein, including the best mode known to the inventors for carrying
out the disclosure. Variations of those preferred embodiments may
become apparent to those of ordinary skill in the art upon reading
the foregoing description. The inventors expect skilled artisans to
employ such variations as appropriate, and the inventors intend for
the disclosure to be practiced otherwise than as specifically
described herein. Accordingly, this disclosure includes all
modifications and equivalents of the subject matter recited in the
claims appended hereto as permitted by applicable law. Moreover,
any combination of the above-described elements in all possible
variations thereof is encompassed by the disclosure unless
otherwise indicated herein or otherwise clearly contradicted by
context.
* * * * *