EP0177316A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for fabricating an ink jet printer nozzle member
Assignee: Panasonic Holdings Corp
•
Filing: 1985-09-30
•
Granted: —
•
Expires: 2005-09-30
Abstract
Abstract In an ink jet printer, a print head (1) comprises a front nozzle member (2) having a front channel (3), a housing (4) secured to the front nozzle member, and a rear nozzle member (7) which defines with the housing a liquid chamber (5) and further defines with the front nozzle member a laminar airflow chamber (10a). The rear nozzle member has a forwardly projecting nozzle (8) and a rear channel (9) extending from the liquid chamber through the projecting nozzle in axial alignment with the front channel (3) to form a meniscus at the front end. The airflow chamber is connected to an air supply for directing air to a point between the front and rear channels (3. 9) so that it creates a sharp pressure gradient along a path therebetween. A dead air region is created in a location adjacent the exit end of the rear channel to cause the meniscus to take a dome-like shape which is stabilized against vibrations and transients. An electric field gradient is established between the front channel and the meniscus to cause the latter to extend toward the front channel and expelled through the front channel. A portion (2a) of the front nozzle member is liquid-repellant to prevent the field distribution from being seriously disturbed by an ink layer formed on it by stray ink particles.
Inventors
- 👤 Masayoshi Miura
- 👤 Kenji Akami
- 👤 Gen Oda
- 👤 Tamotsu Kojima
- 👤 Hiroshi Naito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 14:26
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/135; B41J2/16; B41J2/1621; B41J2/1631; B41J2/1606; B41J2/162; B41J2/1623; B41J2/1626; B41J2/1629; B41J2/1632; B41J2/164; B41J2/1643; B41J2202/00; B41J2202/01; B41J2202/02
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
269 words
An ink jet printer comprising a source of pressurized air (13), a liquid container (6), an ink jet print head (1) comprising a front nozzle member (2) having a front channel (3), a housing (4) secured to said front nozzle member, a rear nozzle member (7) defining with said housing a liquid chamber (5) connected to said container and defining with said front nozzle member a laminar airflow chamber (10), said rear nozzle member (7) having a rear channel (9) extending forwardly from the liquid chamber in axial alignment with said front channel to form a meniscus at the front end thereof, said airflow chamber being connected to said air source for directing air to a point between said front and rear channels so that it makes a sharp turn at the entry into said front channel creating a sharp pressure gradient along a path between the exit ends of said front and rear channels and a dead air region adjacent the exit end of said rear channel, means (11, 6a, 12) for establishing an electric field gradient between said front channel and said meniscus to cause it to extend to and partially expelled through said front channel, and means (15) for connecting said liquid container to said air source so that in the absence of said electric field the liquid pressure in said rear channel is statically balanced with the combined forces of air pressure acting on said meniscus and the surface tension of the liauid, characterized in that said rear nozzle member has a forwardly projecting nozzle (8) whose radial dimensions substantially correspond to said front channel.
Claim 2
Dependent Claim
269 words
An ink jet printer comprising a source of pressurized air (13), a liquid container (6), an ink jet print head (1) comprising a front nozzle member (2) having a front channel (3), a housing (4) secured to said front nozzle member, a rear nozzle member (7) defining with said housing a liquid chamber (5) connected to said container and defining with said front nozzle member a laminar airflow chamber (10), said rear nozzle member (7) having a rear channel (9) extending forwardly from the liquid chamber in axial alignment with said front channel to form a meniscus at the front end thereof, said airflow chamber being connected to said air source for directing air to a point between said front and rear channels so that it makes a sharp turn at the entry into said front channel creating a sharp pressure gradient along a path between the exit ends of said front and rear channels and a dead air region adjacent the exit end of said rear channel, means (11, 6a, 12) for establishing an electric field gradient between said front channel and said meniscus to cause it to extend to and partially expelled through said front channel, and means (15) for connecting said liquid container to said air source so that in the absence of said electric field the liquid pressure in said rear channel is statically balanced with the combined forces of air pressure acting on said meniscus and the surface tension of the liauid, characterized in that said rear nozzle member has a forwardly projecting nozzle (8) whose radial dimensions substantially correspond to said front channel.
Claim 3
Dependent Claim
36 words
An ink jet printer as claimed in claim 1, characterized in that said meniscus is held in a convexed shape on a front face of said projecting nozzle (7) in the absence of said electric field.
Claim 4
Dependent Claim
41 words
An ink jet printer as claimed in claim 1 or 2 characterized in that said rear channel has a front portion located in said projecting nozzle and a rear portion, said front portion having a concave surface or a part-spherical surface.
Claim 5
Dependent Claim
62 words
An ink jet printer as claimed in claim 1, 2 or 3 characterized in that said rear nozzle member satisfies the following relations: where, B = the axial length of said projecting nozzle, L = the distance between said front and rear nozzle members, Df = the diameter of said front channel, and Dr = the outer diameter of said projecting nozzle.
Claim 6
Dependent Claim
42 words
An ink jet printer as claimed in claim 1, 2, 3 or 4, characterized in that a portion of said front nozzle member (2) opposed to said projecting nozzle (8) and surrounding said front channel (3) is capable of repelling said liquid.
Claim 7
Dependent Claim
19 words
An ink jet printer as claimed in claim 5, characterized in that said portion is formed of liquid-repellant material.
Claim 8
Dependent Claim
43 words
An ink jet printer as claimed in any preceding claim, characterized in that a portion of said front nozzle member (2) opposed to said projecting nozzle (8) and the inner wall of said front channel are coated with a layer of liquid-repellant material.
Claim 9
Dependent Claim
43 words
An ink jet printer as claimed in claim 5, 6 or 7 characterized in that a portion of said front nozzle member (2) adjacent to the first-mentioned portion but remote from said projecting nozzle (8) is coated with a layer of liquid-repellant material.
Claim 10
Dependent Claim
42 words
An ink jet printer as claimed in any preceding claim characterized in that the outer wall of said projecting nozzle (8) and a portion of the rear nozzle member (7) adjoining said outer wall are coated with a layer of liquid-repellant material.
Claim 11
Dependent Claim
29 words
An ink jet printer as claimed in claim 9, characterized in that a front end face of said projecting nozzle (8) is coated with a layer of liquid-repellant material.
Claim 12
Dependent Claim
37 words
An ink jet printer as claimed in claim 6, 7, 8, 9 or 10, characterized in that said liquid-repellant material comprises fluoride-containing polymer, inorganic fluoride-containing compound, silicone polymer or a copolymer of fluoride-containing polymer and silicone polymer.
Claim 13
Independent Claim
74 words
A method for fabricating a nozzle member of an ink jet print head, comprising the steps of: a) etching a substrate according to a first pattern from a first surface thereof to a predetermined depth to form a projecting nozzle having a nozzle opening therein; and b) etching said substrate according to a second pattern from a second, opposite surface thereof to form a channel extending to and axially aligned with said nozzle opening.
Claim 14
Independent Claim
74 words
A method for fabricating a nozzle member of an ink jet print head, comprising the steps of: a) etching a substrate according to a first pattern from a first surface thereof to a predetermined depth to form a projecting nozzle having a nozzle opening therein; and b) etching said substrate according to a second pattern from a second, opposite surface thereof to form a channel extending to and axially aligned with said nozzle opening.
Claim 15
Dependent Claim
69 words
A method as claimed in claim 12, characterized in that the step (b) comprises: bl) applying a first layer of an etchant resistive material on said first surface so that said material fills --id nozzle opening and forming a second layer of an etchant resistive material on said second surface excepting a portion which is aligned with said nozzle opening; and b2) immersing said substrate into an etchant solution.
Claim 16
Dependent Claim
32 words
A method as claimed in claim 12 or 13, characterized in that the step (a) is performed for a period of time smaller than the time taken to perform the step (b).
Claim 17
Dependent Claim
17 words
A method as claimed in claim 12,13 or 14 characterized in thai said substrate comprises photosensitive glass.
Claim 18
Dependent Claim
61 words
A method as claimed in claim 12,13 or 14 characterized in thai said substrate comprises an insulator and a layer of material dissimilar to the material that comprises the insulator, characterized in that the step (a) comprises etching said layer of dissimilar material according to said first pattern, and the step (b) comprises etching said insulator according to said second pattern.
Claim 19
Dependent Claim
211 words
A method as claimed in claim 12,13 or 14 characterized in tha the step (a) comprises the steps of: a l ) subjecting a first surface of a photosensitive glass substrate to an ultraviolet first imagewise radiation; a 2 ) heating said substrate to crystallize radiation exposed portions thereof so that an unexposed portion thereof forms an amorphous hollow cylinder extending from the first surface to a second, opposite surface of the substrate; and a3) subjecting said first surface of said substrate to an etchant solution to remove said crystallized portions from the first surface to a predetermined depth to thereby allow part of said amorphous hollow cylinder to project from said substrate, and in that the step (b) comprises: b l ) applying a photoresist layer on said second surface of the substrate; b 2 ) subjecting said photoresist layer to an ultraviolet second imagewise radiation; b 3 ) subjecting said photoresist layer to an etchant solution to remove a portion of the photoresist layer which is not exposed to said second imagewise radiation; b 4 ) subjecting said substrate on the side of said second surface to an etchant solution to remove the inside of said hollow cylinder; and b 5 ) removing said photoresist layer from said substrate.
Claim 20
Dependent Claim
33 words
A method as claimed in claim 17, characterized in that the step (a3) is performed for a period of time smaller than the time period taken to perform the step (b 4 ).
Claim 21
Dependent Claim
96 words
A method as claimed in claim 17 or 18, characterized in that the step (a l ) comprises: applying a first photomask having a ring-shaped opaque portion; and illuminating ultraviolet light to said substrate through said first photomask, and in that the step (b 2 ) comprises: applying a second photomask on said photoresist layer, said second photomask having a circular opaque portion smaller than the outer circumference of said ring-shaped opaque portion and greater than the inner circumference of said ring-shaped opaque portion; and illuminating ultraviolet light to said photoresist layer through said second photomask.
Claim 22
Dependent Claim
72 words
A method as claimed in claim 17, 18 or 19 characterized in that the step (b4) comprises: applying a second layer of an etchant resistive material to said substrate on the side of said first surface so that it fills the inside of said projecting amorphous portion; immersing said substrate in said etchant solution to remove said inside extending to said second layer, further comprising removing said second layer from the substrate.
Claim 23
Independent Claim
38 words
A method as claimed in any one of claims 17 to 20, further comprising the steps of subjecting said substrate after the step (b S ) to ultraviolet radiation and heating the substrate to crystallize said amorphous cylinder.
Claim 24
Independent Claim
36 words
A method as claimed in any one of claims 17 to 21, further comprising the step of applying a light shielding layer to said substrate on said second side prior to the step (b 1 ).
Claim 25
Independent Claim
32 words
A method as claimed in any one of claims 17 to 22, further comprising the step of roughening said second side surface of said substrate prior to the step (b l ).
Claim 26
Dependent Claim
214 words
A method as claimed in claim 12, characterized in that the step (a) comprises the steps of: a l ) subjecting a first surface of a photosensitive glass substrate to an ultraviolet first imagewise radiation; a 2 ) heating the substrate to crystallize radiation-exposed portions so that an unexposed portion forms an amorphous hollow cylinder extending from the first surface to a second surface of the substrate; and a3) subjecting said first and second surfaces of said substrate to an etchant solution to etch said crystallized portions from the first surface to a predetermined depth to thereby allow a first part of said amorphous hollow cylinder to project from the first surface and etch said crystallized portions from the second surface to a predetermined depth to thereby allow a second part of said amorphous hollow cylinder to project from said second surface, and in that the step (b) comprises the steps of: b l ) applying a layer of etchant resistive material to the etched second surface outside of said projecting second part; b 2 ) subjecting the second surface of said substrate to an etchant solution to remove the inside of said hollow cylinder extending from said second surface to said first surface; and b 3 ) removing said layer from the substrate.
Claim 27
Dependent Claim
69 words
A method as claimed in claim 24, characterized in that the step (b 2 ) comprises: applying a second layer of etchant resistive material on the entire area of said substrate on the side of said first surface so that it fills the inside of said projecting first part; and immersing said substrate in an etchant solution to remove said inside from said second surface to said second layer.
Claim 28
Dependent Claim
33 words
A method as claimed in claim 24 or 25 characterized in that the step (a3) is performed for a period of time smaller than the time period taken to perform the step' (e).
Claim 29
Dependent Claim
28 words
A method as claimed in claim 24,25 or 26 further comprising the step of lapping said substrate on the side of said second surface to a predetermined depth.
Claim 30
Dependent Claim
32 words
A method as claimed in claim 24,25,26 or 27 further comprising subjecting said substrate after the step (b 3 ) to ultraviolet radiation and heating the substrate to crystallize said amorphous cylinder.
Claim 31
Independent Claim
47 words
A method as claimed in any of claims 12 to 28, characterized by spraying liquid-repellant material onto a surface of said nozzle member and forcing an airstream through the channel of said nozzle member in the same direction as the direction of movement of the sprayed material.
Claim 32
Independent Claim
47 words
A method as claimed in any of claims 12 to 28, characterized by spraying liquid-repellant material onto a surface of said nozzle member and forcing an airstream through the channel of said nozzle member in a direction opposite to the direction of movement of the sprayed material.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.