U.S. patent application number 13/845313 was filed with the patent office on 2014-09-18 for oxygen impermeable umbilicals for ink in a printer.
This patent application is currently assigned to Xerox Corporation. The applicant listed for this patent is XEROX CORPORATION. Invention is credited to Robert Mark Jacobs, John David Means, Anthony Yeznach.
Application Number | 20140267512 13/845313 |
Document ID | / |
Family ID | 51358439 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140267512 |
Kind Code |
A1 |
Means; John David ; et
al. |
September 18, 2014 |
OXYGEN IMPERMEABLE UMBILICALS FOR INK IN A PRINTER
Abstract
A liquid ink delivery system for use in an inkjet printer
includes a plurality of conduits. Each conduit is configured to
deliver liquid ink from reservoirs to printheads. The conduits are
essentially comprised of a first material which is non-reactive
with the liquid ink and which does not facilitate cooling or
congealing of the liquid ink as the ink passes through the
conduits. The conduits also include coatings applied to the first
material that have further properties suited to delivery of ink and
additives within the liquid ink. In one embodiment, an oxygen
impermeable coating is applied to the conduit to reduce the risk of
the ink or an additive within the ink oxidizes during transport
through the conduit.
Inventors: |
Means; John David; (Newberg,
OR) ; Jacobs; Robert Mark; (Tigard, OR) ;
Yeznach; Anthony; (Wilsonville, OR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
XEROX CORPORATION |
Norwalk |
CT |
US |
|
|
Assignee: |
Xerox Corporation
Norwalk
CT
|
Family ID: |
51358439 |
Appl. No.: |
13/845313 |
Filed: |
March 18, 2013 |
Current U.S.
Class: |
347/85 |
Current CPC
Class: |
B41J 2/175 20130101 |
Class at
Publication: |
347/85 |
International
Class: |
B41J 2/175 20060101
B41J002/175 |
Claims
1. A conduit for transporting liquid ink comprising: a body having
a first end and a second end; a lumen extending through the body
between the first end and the second end, the body being
essentially comprised of a first material that is non-reactive with
liquid ink; and a first coating applied to a surface of the body,
the first coating essentially comprised of a second material that
is impermeable to oxygen.
2. The conduit of claim 1 wherein the first coating and the surface
of the body are integrally formed and essentially comprise
homogenous material.
3. The conduit of claim 2 wherein the homogenous material is
polyvinylidene difluoride.
4. The conduit of claim 1 wherein the first coating is applied to
an outside surface of the body.
5. The conduit of claim 1 further comprising: a second coating
essentially comprised of a third material that is impermeable to
dye, the second coating integrally formed with the first
coating.
6. The conduit of claim 1 further comprising: a second coating
essentially comprised of a third material that is impermeable to
dye, the second coating integrally formed with the body.
7. The conduit of claim 4 further comprising: a second coating
essentially comprised of a third material that is impermeable to
dye, the second coating interposed between the first coating and
the outside surface of the body.
8. The conduit of claim 4 further comprising: a second coating
essentially comprised of a third material that is impermeable to
dye, the first coating interposed between the second coating and
the outside surface of the body.
9. The conduit of claim 1 further comprising: a second coating
essentially comprised of a third material that is impermeable to
dye, the body, the first coating, and the second coating being
flexible.
10. The conduit of claim 1 wherein the first material is
silicone.
11. The conduit of claim 1 wherein the second material is
Viton.
12. An ink umbilical assembly for transporting liquid ink to a
printhead comprising: a plurality of conduits essentially comprised
of a first material that is non-reactive with liquid ink, the
plurality of conduits having an outer surface; and a coating
applied to the outer surface of the plurality of conduits, the
coating essentially comprised of a second material that is
impermeable to oxygen.
13. The ink umbilical assembly of claim 12 wherein the first
coating and the surface of the conduit are integrally formed and
essentially comprise a homogenous material.
14. The ink umbilical assembly of claim 13 wherein the homogenous
material is polyvinylidene difluoride.
15. The ink umbilical assembly of claim 12 wherein the first
coating is applied to the outer surface of the plurality of
conduits.
16. The ink umbilical assembly of claim 12 further comprising: a
second coating essentially comprised of a third material that is
impermeable to dye, the second coating integrally formed with the
first coating.
17. The ink umbilical assembly of claim 12 further comprising: a
second coating essentially comprised of a third material that is
impermeable to dye, the second coating integrally formed with the
plurality of conduits.
18. The ink umbilical assembly of claim 15 further comprising: a
second coating essentially comprised of a third material that is
impermeable to dye, the second coating interposed between the first
coating and the outer surface of the plurality of conduits.
19. The ink umbilical assembly of claim 15 further comprising: a
second coating essentially comprised of a third material that is
impermeable to dye, the first coating interposed between the second
coating and the outer surface of the plurality of conduits.
20. The ink umbilical assembly of claim 12 further comprising: a
second coating essentially comprised of a third material that is
impermeable to dye, the plurality of conduits, the first coating,
and the second coating being flexible.
21. The ink umbilical assembly of claim 12 wherein the first
material is silicone.
22. The ink umbilical assembly of claim 12 wherein the second
material is Viton.
23. An inkjet printer comprising: a printhead having a plate with a
plurality of openings; a plurality of ink reservoirs; and an ink
umbilical assembly configured to transport liquid ink from the
plurality of ink reservoirs to the printhead, the ink umbilical
assembly including: a plurality of conduits essentially comprised
of a first material that is non-reactive with liquid ink, the
plurality of conduits having an outer surface, each conduit of the
plurality of conduits having a first end configured to be coupled
to the an ink reservoir of the plurality of ink reservoirs and a
second end configured to be coupled to an opening of the plurality
of openings; and a first coating applied to the outer surface of
the plurality of conduits, the coating essentially comprised of a
second material that is impermeable to oxygen.
24. The inkjet printer of claim 23 wherein the first coating and
the outer surface of the plurality of conduits are integrally
formed and essentially comprise a homogenous material.
25. The inkjet printer of claim 24 wherein the homogenous material
is polyvinylidene difluoride.
26. The inkjet printer of claim 23 wherein the first coating is
applied to the outer surface of the plurality of conduits.
27. The inkjet printer of claim 23 further comprising: a second
coating essentially comprised of a third material that is
impermeable to dye, the second coating integrally formed with the
first coating.
28. The inkjet printer of claim 23 further comprising: a second
coating essentially comprised of a third material that is
impermeable to dye, the second coating integrally formed with the
plurality of conduits.
29. The inkjet printer of claim 26 further comprising: a second
coating essentially comprised of a third material that is
impermeable to dye, the second coating interposed between the first
coating and the outer surface of the plurality of conduits.
30. The inkjet printer of claim 26 further comprising: a second
coating essentially comprised of a third material that is
impermeable to dye, the first coating interposed between the second
coating and the outer surface of the plurality of conduits.
31. The inkjet printer of claim 23 further comprising: a second
coating essentially comprised of a third material that is
impermeable to dye, the plurality of conduits, the first coating,
and the second coating being flexible.
32. The inkjet printer of claim 23 wherein the first material is
silicone.
33. The inkjet printer of claim 23 wherein the second material is
Viton.
34. The ink jet printer of claim 23 further comprising: liquid ink
transported through the plurality of conduits, the liquid ink
including at least one additive capable of being oxidized.
Description
TECHNICAL FIELD
[0001] This disclosure relates generally to machines that move
thermally treated fluid from a supply through a conduit to a
printhead.
BACKGROUND
[0002] The word "printer" as used herein encompasses any apparatus,
such as a digital copier, book marking machine, facsimile machine,
multi-function machine, etc., that produces an image with a
colorant on recording media for any purpose. Printers that form an
image on a surface of an image receiving member and then transfer
the image to recording media are referenced in this document as
indirect printers. Indirect printers typically use intermediate
transfer, transfix, or transfuse members to facilitate the transfer
and fusing of the image from the image receiving member to the
recording media. In general, such printing systems typically
include a colorant applicator, such as a printhead, that forms an
image with colorant on the image receiving member. Recording medium
is fed into a nip formed between the surface of the image receiving
member and a transfix roller to enable the image to be transferred
and fixed to the print medium so the image receiving member can be
used for formation of another image.
[0003] In ink imaging systems having intermediate image receiving
members, ink is loaded into the system and delivered through a
conduit system as liquid ink to a printhead for jetting onto a
surface of an image receiving member. The ink can be in the form of
aqueous ink, pigment and dye resin based aqueous ink, MICR ink, UV
ink, and solid ink. When the ink is solid phase change ink, the
solid phase change ink is transported through a feed chute by a
feed mechanism for delivery to a melting device. The melting device
heats the solid ink so it melts and then is delivered through the
conduit system. Regardless of the ink type, once in the conduit
system, the liquid ink is maintained at a temperature that enables
ejection of the ink by the inkjet ejectors in the printhead, while
preserving sufficient tackiness to enable the ink to adhere to the
surface of the image receiving member. Accordingly, to transport
the liquid ink, the conduit system must be essentially comprised of
a material which does not facilitate adhesion or congealing of the
liquid ink. Additionally, because the liquid ink is heated to a
high temperature, chemical reactions between the ink and the
conduit system are able to occur more readily. Conduit systems for
liquid ink delivery that address these issues are desirable.
SUMMARY
[0004] A conduit has been developed that transports liquid ink
while attenuating or preventing chemical reactions with the conduit
or substances seeping through the conduit. The conduit includes a
body having a first end and a second end and a lumen extending
through the body between the first end and the second end. The body
is essentially comprised of a first material that is non-reactive
with liquid ink. A first coating is applied to a surface of the
body, and the first coating is essentially comprised of a second
material that is impermeable to oxygen.
[0005] An ink umbilical assembly has been developed that transports
liquid ink while attenuating or preventing chemical reactions with
the assembly or substances seeping through a conduit in the
assembly. The ink umbilical assembly includes a plurality of
conduits essentially comprised of a first material that is
non-reactive with liquid ink. The plurality of conduits has an
outer surface. A coating is applied to the outer surface of the
plurality of conduits, and the coating is essentially comprised of
a second material that is impermeable to oxygen.
[0006] An inkjet printer has been developed that transports liquid
while attenuating or preventing chemical reactions with a conduit
in the printer or substances seeping through the conduit in the
printer. The printer includes a printhead having a plate with a
plurality of openings, a plurality of ink reservoirs, and an ink
umbilical assembly. The ink umbilical assembly is configured to
transport liquid ink from the plurality of ink reservoirs to the
printhead. The ink umbilical assembly includes a plurality of
conduits essentially comprised of a first material that is
non-reactive with liquid ink. The plurality of conduits has an
outer surface, and each conduit of the plurality of conduits has a
first end configured to be coupled to the an ink reservoir of the
plurality of ink reservoirs and a second end configured to be
coupled to an opening of the plurality of openings. A first coating
is applied to the outer surface of the plurality of conduits, and
the coating is essentially comprised of a second material that is
impermeable to oxygen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The foregoing aspects and other features of a conduit and an
ink umbilical assembly for use in an inkjet printer to transport
liquid ink are explained in the following description, taken in
connection with the accompanying drawings.
[0008] FIG. 1 is an enlarged perspective view of an ink umbilical
assembly used in an ink delivery system.
[0009] FIG. 2 is a schematic perspective view of a conduit
configured for use in the ink umbilical assembly of FIG. 1.
[0010] FIG. 3 is a schematic cross-sectional view of a conduit
configured for use in the ink umbilical assembly of FIG. 1.
[0011] FIG. 4 is a schematic cross-sectional view of another
conduit configured for use in the ink umbilical assembly of FIG.
1.
[0012] FIG. 5 is a schematic cross-sectional view of another
conduit configured for use in the ink umbilical assembly of FIG.
1.
[0013] FIG. 6 is a block diagram of connections for a prior art ink
delivery system in an inkjet printer.
DETAILED DESCRIPTION
[0014] By way of example, a phase change ink printer 10 includes a
liquid ink delivery system of the prior art as shown in FIG. 6. The
printer 10, however, can alternatively be configured to print using
aqueous ink, pigment and dye resin based aqueous ink, MICR ink, UV
ink, and solid ink. The system 10 includes reservoirs 14A, 14B,
14C, and 14D, printheads 18A, 18B, 18C, and 18D, staging areas
22A.sub.1-4, 22B.sub.1-4, 22C.sub.1-4, and 22D.sub.1-4, and
conduits 26A.sub.1-4, 26B.sub.1-4, 26C.sub.1-4, and 26D.sub.1-4.
The term conduit as used herein refers to a body having a
passageway through the body for transport of a liquid or a gas.
[0015] Each reservoir 14A, 14B, 14C, and 14D is configured to
collect and retain liquid ink of a single color. As shown in FIG.
6, reservoir 14A contains cyan colored ink C, reservoir 14B
contains magenta colored ink M, reservoir 14C contains yellow
colored ink Y, and 14D contains black colored ink K. In alternative
embodiments, liquid ink of other colors can be used. Each reservoir
14A, 14B, 14C, and 14D is coupled to each of the printheads 18A,
18B, 18C, and 18D via the staging areas 22A.sub.1-4, 22B.sub.1-4,
22C.sub.1-4, and 22D.sub.1-4, and conduits 26A.sub.1-4,
26B.sub.1-4, 26C.sub.1-4, and 26D.sub.1-4. The liquid ink delivery
system shown in FIG. 6 includes four reservoirs and four
printheads. In alternative embodiments, however, liquid ink
delivery systems can include more or fewer reservoirs and
printheads.
[0016] The liquid ink in the staging areas 22A.sub.1-4,
22B.sub.1-4, 22C.sub.1-4, and 22D.sub.1-4 is pressurized to
facilitate delivery of the ink to a printhead 18A, 18B, 18C, or
18D. When a printhead 18A, 18B, 18C, or 18D needs additional ink, a
valve is opened to enable ink from the respective staging area
22A.sub.1-4, 22B.sub.1-4, 22C.sub.1-4, or 22D.sub.1-4 to flow
through the respective conduit 26A.sub.1-4, 26B.sub.1-4,
26C.sub.1-4, or 26D.sub.1-4 to the respective printhead 18A, 18B,
18C, or 18D. Accordingly, each printhead 18A, 18B, 18C, and 18D
receives ink from each of the four reservoirs to enable each
printhead to eject all four colors of ink, namely, black, cyan,
magenta, and yellow.
[0017] The spatial relationships between the reservoirs 14A, 14B,
14C, and 14D and the printheads 18A, 18B, 18C, and 18D are not
accurately depicted in the block diagram shown in FIG. 6. Instead,
the reservoirs 14A, 14B, 14C, and 14D and the printheads 18A, 18B,
18C, and 18D are arranged in FIG. 6 to illustrate the connection
points for the overlapping conduits 26A.sub.1-4, 26B.sub.1-4,
26C.sub.1-4, and 26D.sub.1-4. Thus, the actual distances between
the reservoirs 14A, 14B, 14C, and 14D and printheads 18A, 18B, 18C,
and 18D are longer than shown in 6. While independent conduits
26A.sub.1-4, 26B.sub.1-4, 26C.sub.1-4, and 26D.sub.1-4 like those
shown in FIG. 6 are able to couple the reservoirs 14A, 14B, 14C,
and 14D to each of the printheads 18A, 18B, 18C, and 18D
effectively, such a configuration is inefficient in terms of space
required for routing the conduits 26A.sub.1-4, 26B.sub.1-4,
26C.sub.1-4, and 26D.sub.1-4 and in terms of maintaining the
particular environmental conditions important for the
transportation of the liquid ink. For example, longer conduits,
such as the conduit 26D.sub.1 between the black ink reservoir 14D
and the printhead 18A, are sufficiently long that under some
environmental conditions, the liquid ink can at least partially
solidify in the conduit 26D.sub.1 as it is being transported from
the reservoir 14D to the printhead 18A.
[0018] Accordingly, to address these and other issues, as well as
to provide conduits that are flexible and are attached to one
another to allow relative motion for printer operation and
reasonable service access, an ink umbilical assembly, such as the
ink umbilical assembly 100 shown in FIG. 1 is used. The term "ink
umbilical assembly" as used in this document means one or more
pluralities of conduits that are assembled in association with a
heater to maintain the ink in each plurality of conduits at a
temperature different than the ambient temperature. The exemplary
ink umbilical assembly 100 described in more detail below is
flexible to enable relative movement between adjacent printheads
and between printheads and reservoirs.
[0019] The ink umbilical assembly 100 shown in FIG. 1 includes a
first plurality of conduits 126, which includes conduits 130A,
130B, 130C and 130D and a second plurality of conduits 134, which
includes conduits 138A, 138B, 138C and 138D. Interposed between the
first plurality of conduits 126 and the second plurality of
conduits 134 is a heater 142. In at least one embodiment, each
plurality of conduits 126, 134 is comprised of independent conduits
coupled together to form a plurality so the conduits are generally
parallel to one another along the length of the ink umbilical
assembly 100. In at least another embodiment, each plurality of
conduits 126, 134 is formed as a single structure, for example, by
extrusion, as shown in FIG. 1. In at least one embodiment, the
conduits 130A-D and 138A-D are substantially semi-circularly shaped
to provide a relatively flat surface to facilitate joining the
first and second pluralities of conduits 126, 134 to the heater
142. The resulting structure promotes heat transfer from the heater
142 into the conduits 130A-D and 138A-D and provides thermal mass
around the heater 142 to improve heat spread to reduce the
likelihood of hot spots on the first and second pluralities of
conduits 126, 134. Thus, the arrangement of conduits 130A-D and
138A-D on both sides of the heater 142 results in greater
efficiency of the heater 142.
[0020] Each of the conduits 130A-D and 138A-D are substantially
similar to one another. Turning now to FIG. 2, conduit 130A, by way
of example to represent each of the conduits 130A-D and 138A-D, is
described in greater detail. The conduit 130A has a body 146
through which a lumen 164 extends. The body is formed in a tubular
shape and has a first end 144, a second end 148, and a length 152
extending from the first end 144 to the second end 148. The body
146 of the conduit 130A is essentially comprised of a first
material 154. The body 146 of the conduit 130A has an internal
surface 156 and an opposite external surface 160, both of which
extend along the length 152 of the conduit 130A from the first end
144 to the second end 148. The lumen 164 is the space adjacent to
the internal surface 156 of the conduit 130A and is configured to
transport liquid ink through the conduit 130A.
[0021] The first end 144 is coupled to one of the reservoirs 14A,
14B, 14C, or 14D (shown in FIG. 6) and the second end 148 is
coupled to one of the printheads 18A, 18B, 18C, or 18D (shown in
FIG. 6) such that when liquid ink is transported through the
conduit 130A, the ink is transported from the reservoir to the
printhead. The liquid ink and the conduit 130A are maintained at a
temperature sufficient to allow the liquid ink to flow along the
conduit 130A without cooling or congealing. The temperature to
which the conduit is heated also facilitates reactions between
chemicals contained in the ink and chemicals contained in the
conduit 130A. Accordingly, the ink and the conduit 130A should be
essentially comprised of materials which are not reactive with one
another at the temperature at which the conduit 130A is typically
maintained.
[0022] More specifically, ink is essentially comprised of specific
chemicals to produce ink material having predetermined properties
suited to the printing process. Chemicals added to the ink to
result in predetermined properties are also known as additives. For
example, some phase change inks are formulated with additives to
cause the ink to have a predetermined melting temperature.
Additionally, some inks are formulated with additives to cause each
color of ink to have a predetermined hue. Additionally, some inks
are formulated with additives to cause the ink to have a
predetermined viscosity and tackiness such that the ink flows
through the printing system and adheres to the print media. For
example, the additive Sylvalite is added to ink to cause the ink to
have a predetermined viscosity and tackiness when it is heated to a
predetermined temperature. Some additives have chemical properties
which make them more reactive or less reactive with other
chemicals. For example, Sylvalite is reactive with oxygen such that
exposure of Sylvalite to oxygen at an elevated temperature causes
Sylvalite to oxidize, thereby changing the chemical and physical
properties of the ink. Additionally, some additives are more
difficult or less difficult and more expensive or less expensive to
produce. Accordingly, the additives added to ink to cause the ink
to have predetermined properties are selected based on their
chemical properties as well as their cost.
[0023] Similarly, conduits are essentially comprised of specific
chemicals that provide the conduit with predetermined properties
suited to the printing process. For example, some conduits are
essentially comprised of a material formulated with specific
chemicals such that the conduits are non-reactive with the heated,
liquid ink. Conduits can be essentially comprised of materials
formulated with specific chemicals to make the conduit bodies
non-reactive with additives included in the heated, liquid ink;
impermeable to oxygen and other gases such as carbon dioxide;
flexible; reduce the likelihood that the ink does not adhere to or
congeal within the lumen; and impermeable to ink pigments or dyes.
One or more of the specific chemicals can be used together or
separately to impart one or more of these properties to the conduit
provided the chemicals do not react adversely with one another. As
used herein, ink pigments or dyes are colorant materials added to
ink to impart a particular color hue to the ink.
[0024] To illustrate the importance of formulating the ink and the
conduits with compatible materials, in one embodiment, by way of
example, the first material of the conduits is essentially
comprised of silicone and the ink includes the additive Sylvalite.
Silicone is a desirable material to use for the first material of
conduits because it produces conduits that are substantially
flexible, that do not facilitate adhesion or congealing of the
liquid ink within the lumen, and that are non-reactive with a large
variety of chemicals, including Sylvalite. However, silicone is
also highly permeable to oxygen. In alternative embodiments,
perfluorinated ethers and perfluorinated hydrocarbon elastomers can
be used for the first material of conduits. Sylvalite is a
desirable chemical to use as an additive in phase change ink
because it produces ink with a predetermined viscosity and
tackiness at an elevated temperature and because it is inexpensive.
However, Sylvalite is also reactive with oxygen such that exposure
to oxygen at elevated temperatures changes the chemical and
physical properties of the Sylvalite. Accordingly, when liquid ink
including Sylvalite passes through the conduits essentially
comprised of silicone, the Sylvalite does not react with the
silicone in the conduits, but oxygen passes through the conduits
and oxidizes the Sylvalite, thereby changing the chemical and
physical properties of the ink. Accordingly, as described in more
detail below, exemplary conduits further include at least one
coating applied to the external surfaces. While the conduits can be
used with a variety of ink types, they are especially useful for
transporting melted phase change inks as these inks have additives
that can be reactive than those found in other inks and the ink and
additives are heated and maintained at temperatures that encourage
chemical reactions.
[0025] Shown in FIG. 3, the conduit 130A' is substantially similar
to the conduit 130A (shown in FIG. 2). Both the conduit 130A and
the conduit 130A' are essentially comprised of a first material
154. The conduit 130A' differs, however, from the conduit 130A in
that the conduit 130A' includes a first coating 168 essentially
comprised of a second material 172 applied to the external surface
160 of the conduit 130A'. The first material 154 is substantially
flexible, does not facilitate adhesion or congealing of liquid ink,
and is non-reactive with a large variety of materials. The second
material 172 is substantially flexible and is impermeable to
oxygen. The first material is, for example, silicone, and the
second material is, for example, Viton. In alternative embodiments,
Tedlar, Kynar, Saran, Teflon or other vapor deposited metals and
polymers can be used as the second material. Applying the first
coating 168 essentially comprised of a second material 172 that is
impermeable to oxygen to the external surface 160 of the conduit
130A' essentially comprised of the first material 154 that is
non-reactive with a large variety of materials, renders the conduit
130A' suitable for transporting a large variety of liquid inks. The
first coating 168 on the conduit 130A' can be fabricated using
coextrusion, flow coating, dipping, spraying, coating and/or
painting.
[0026] More specifically, the conduit 130A' is rendered suitable
for transporting inks including additives prone to oxidization. The
ink including the oxidization prone additive does not react with
the non-reactive first material 154 in the conduit 130A' and the
oxygen impermeability of the second material 172 of the first
coating 168 prevents oxygen from passing through the conduit 130A'
thereby reducing the risk that the additive oxidizes. Accordingly,
the first coating 168 increases the versatility of the conduit
130A' by rendering it suitable for transporting a greater variety
of inks including inks having oxidization prone additives, some of
which are relatively low cost additives.
[0027] In at least one embodiment, the first coating 168 is
integrally formed with, rather than being applied to, the external
surface 160 of the conduit 130A'. Integrally forming the first
coating 168 with the external surface 160 achieves the same result
as applying the first coating 168 to the external surface 160, but
results in a single unitary piece essentially comprised of a
homogenous material. This integration of the two materials is
advantageous for ease of production of the ink umbilical assembly.
In at least one embodiment, the homogenous material is
polyvinylidene fluoride.
[0028] Shown in FIG. 4, the conduit 130A'' is substantially similar
to the conduit 130A' (shown in FIG. 3). Both the conduit 130A' and
the conduit 130A'' are essentially comprised of a first material
154 and include a first coating 168 essentially comprised of a
second material 172 applied to the external surface 160 of the
conduit 130A'. The conduit 130A'' differs, however, from the
conduit 130A' in that the conduit 130A'' also includes a second
coating 176 essentially comprised of a third material 180 applied
to the first coating 168. The third material 180 is substantially
flexible and is impermeable to pigments or dyes. Applying the
second coating 176 essentially comprised of a third material 180
that is impermeable to pigments or dyes to the first coating 168
essentially comprised of the second material 172 that is
impermeable to oxygen applied to the conduit 130A'' essentially
comprised of the first material 154 that is non-reactive with a
large variety of materials, renders the conduit 130A'' suitable for
transporting a large variety of liquid inks. The first coating 168
and the second coating 176 on the conduit 130A'' can be fabricated
using coextrusion, flow coating, dipping, spraying, coating and/or
painting.
[0029] More specifically, the conduit 130A'' is rendered suitable
for transporting liquid inks including additives prone to
oxidization and pigments or dyes prone to migration through
materials. The ink including the oxidization prone additive and
migration prone pigments or dyes does not react with the
non-reactive first material 154 in the conduit 130A'' and the
oxygen impermeability of the second material 172 of the first
coating 168 prevents oxygen from passing through the conduit 130A''
thereby preventing exposure of the oxidization prone additive to
oxygen. Additionally, the pigment or dye impermeability of the
third material 180 of the second coating 176 prevents pigments or
dyes from passing through the conduit 130A'' thereby reducing the
risk of migration of the pigments or dyes out of the ink and/or
into other adjacent conduits. Accordingly, the second coating 176
increases the versatility of the conduit 130A'' by rendering the
conduit 130A'' suitable for transporting a greater variety of inks
including inks having oxidization prone additives and having
migration prone pigments or dyes, some of which are relatively low
cost additives.
[0030] In this embodiment, the first coating 168 is interposed
between the second coating 176 and the external surface 160 of the
conduit 130A''. This arrangement allows oxygen to permeate from
outside the ink umbilical assembly 100 (shown in FIG. 1) through
the second coating 176, but not through the first coating 168.
Likewise, this arrangement allows pigments or dyes in the liquid
ink to migrate from the liquid ink within the lumen 164 through the
conduit 130A'' and through the first coating 168, but not through
the second coating 176.
[0031] In at least one embodiment, the second coating 176 is
integrally formed with, rather than applied to, the first coating
168. Integrally forming the second coating 176 with the first
coating 168 achieves the same result as applying the second coating
176 to the first coating 168, but results in a single unitary
piece. This is advantageous for ease of production of the ink
umbilical assembly 100 (shown in FIG. 1). The second coating 176 is
able to be integrally formed with the first coating 168 whether the
first coating is applied to or integrally formed with the conduit
130A''.
[0032] Shown in FIG. 5, the conduit 130A''' is substantially
similar to the conduit 130A'' (shown in FIG. 4). Both the conduit
130A'' and the conduit 130A''' are essentially comprised of a first
material 154, include a first coating 168 essentially comprised of
a second material 172, and include a second coating 176 essentially
comprised of a third material 180. The conduit 130A''' differs,
however, from the conduit 130A'' in that the second coating 176 is
interposed between the first coating 168 and the external surface
160 of the conduit 130A'''. Interposing the second coating 176
between the first coating 168 and the external surface 160 of the
conduit 130A''' achieves the same result as interposing the first
coating 168 between the second coating 176 and the external surface
160 of the conduit 130A'', but this arrangement prevents oxygen
from permeating from outside the ink umbilical assembly 100 (shown
in FIG. 1) through the first coating 168 and thus through the
second coating 176. Likewise, this arrangement prevents pigments or
dyes in the liquid ink from migrating from the liquid ink within
the lumen 164 through the second coating 176 and thus through the
first coating 168.
[0033] In at least one embodiment, the first coating 168 is
integrally formed with, rather than applied to, the second coating
176. Integrally forming the first coating 168 with the second
coating 176 achieves the same result as applying the first coating
168 to the second coating 176, but results in a single unitary
piece. This is advantageous for ease of production of the ink
umbilical assembly. The first coating 168 is able to be integrally
formed with the second coating 176 whether the second coating 176
is applied to or integrally formed with the conduit 130A'''.
[0034] In at least one alternative embodiment, the conduit 130A,
130A', 130A'', or 130A''' includes an additional coating or a
number of additional coatings. An additional coating is essentially
comprised of materials having additional properties suited to the
printing process. In at least one other alternative embodiment, a
coating or number of coatings, for example first coating 168 and
second coating 176, are applied to the internal surface 156 of the
conduit 130A, 130A', 130A'', or 130A''' rather than the external
surface 160. In this alternative embodiment, the coating(s) applied
to the internal surface 156 are non-reactive with a large variety
of chemicals and do not facilitate adhesion or congealing of the
liquid ink.
[0035] It will be appreciated that some or all of the
above-disclosed features and other features and functions or
alternatives thereof, may be desirably combined into many other
different systems, apparatus, devices, or applications. Various
presently unforeseen or unanticipated alternatives, modifications,
variations, or improvements therein may be subsequently made by
those skilled in the art, which are also intended to be encompassed
by the following claims.
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