Prosecution Insights
Last updated: April 19, 2026
Application No. 18/172,425

METHOD FOR MANUFACTURING LIQUID EJECTION HEAD AND LIQUID EJECTION HEAD

Final Rejection §102§103
Filed
Feb 22, 2023
Examiner
CAZAN, LIVIUS RADU
Art Unit
3729
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Canon Kabushiki Kaisha
OA Round
2 (Final)
62%
Grant Probability
Moderate
3-4
OA Rounds
3y 7m
To Grant
88%
With Interview

Examiner Intelligence

Grants 62% of resolved cases
62%
Career Allow Rate
587 granted / 940 resolved
-7.6% vs TC avg
Strong +25% interview lift
Without
With
+25.4%
Interview Lift
resolved cases with interview
Typical timeline
3y 7m
Avg Prosecution
48 currently pending
Career history
988
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
42.7%
+2.7% vs TC avg
§102
28.0%
-12.0% vs TC avg
§112
23.7%
-16.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 940 resolved cases

Office Action

§102 §103
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claim(s) 9 and 10 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kimura (US2014/0071203A1). Kimura discloses the claimed invention as follows (refer to Figs. 1, 3, 4 and 24): Claim 9. A liquid ejection head (411) comprising: a substrate (1 with 2 and 31), comprising: a first surface (bottom surface of 2); a second surface (31a, Fig. 3) on a side opposite to the first surface; a plurality of liquid ejection ports (4; see [0051]) that open on the second surface; a liquid supply port (9; see [0051]) that opens on the first surface in correspondence with each of the liquid ejection ports; a flow path (5 with 6 and 7 and 8) that connects the liquid supply port and a liquid ejection port to each other (see Fig. 2) such that the liquid supply port and the liquid ejection port do not linearly communicate with each other in a direction intersecting with the first surface and the second surface (see Fig. 1); a perfluoropolyether (see [0108]) liquid repellent film (32 on 31a, Fig. 3) formed on the second surface; and a film (32a, Fig. 3) formed inside the liquid ejection port, wherein each dedicated flow path connecting one liquid supply port and one corresponding liquid ejection port includes a portion (e.g. 6, 7 in Fig. 1) extending in a direction parallel to the first surface and the second surface, wherein the supply port and the liquid ejection port do not overlap each other when viewed in a direction perpendicular to the first surface and the second surface (this is evident from Fig. 1), wherein film formed inside the liquid ejection port of the substrate is more hydrophilic than the perfluoropolyether1 liquid repellent film, wherein the film formed inside the ejection port comprises a portion of the perfluoropolyether liquid repellent film remaining inside the liquid ejection port and hydrophilized by plasma generated from a side of the first surface toward a side of the second surface through the flow path2. Claim 10. The liquid ejection head according to claim 9, wherein the film formed inside the liquid ejection port is continuous with the liquid repellent film (see Fig. 3)). Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claim(s) 9-11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tokuno (JP2015150768A). Tokuno discloses the claimed invention as follows (refer to Figs. 3, 17 and 18): Claim 9. A liquid ejection head (structure of Fig. 3) comprising: a substrate (31), comprising: a first surface (lower surface of 31 in Fig. 3); a second surface (upper surface of 31 in Fig. 3) on a side opposite to the first surface; a plurality of liquid ejection ports (1) that open on the second surface; a liquid supply port (45) that opens on the first surface in correspondence with each of the liquid ejection ports (see [0032]-[0034]; there are plural pressure chambers 38 and, therefore, plural corresponding liquid supply ports); a flow path (34 with 38) that connects the liquid supply port and the liquid ejection port to each other such that the liquid supply port and the liquid ejection port do not linearly communicate with each other in a direction intersecting with the first surface and the second surface (see Fig. 3); a perfluoropolyether liquid repellent film (4, Fig. 16; see [0016]) formed on the second surface; and a film (see film on sides of nozzle hole 1, in Fig. 18) formed inside the liquid ejection port, wherein each dedicated flow path connecting one liquid supply port and one corresponding liquid ejection port includes a portion (see Fig. 3) extending in a direction parallel to the first surface and the second surface, wherein the supply port and the liquid ejection port do not overlap each other when viewed in a direction perpendicular to the first surface and the second surface (see Fig. 3), wherein the film formed inside the liquid ejection port is more hydrophilic3 than the perfluoropolyether liquid repellent film, and wherein the film formed inside the ejection port comprises a portion of the perfluoropolyether liquid repellent film remaining inside the liquid ejection port and hydrophilized by plasma generated from a side of the first surface toward a side of the second surface through the flow path4. Claim 10. The liquid ejection head according to claim 9, wherein the film formed inside the liquid ejection port is continuous with the liquid repellent film (see Fig. 18)). Claim 11. The liquid ejection head according to claim 9, wherein an F atom concentration of the film formed inside the liquid ejection port is 0.9 or less when an F atom concentration of the liquid repellent film is defined as 1. Refer to footnote 2. It is readily apparent that at the concentration of F atoms tends to 0 in the direction toward the first surface. Therefore, a region must exist, distal from the second surface, wherein the concentration of F atoms is 90% or less of the concentration of F atoms in film 4 on the second surface. Whereas Tokuno discloses bonding the nozzle plate 2 to the plate 35 within the first day after the removal process, Tokuno does not mention the liquid ejection head as a whole being assembled within the first day. The rejection relies upon the fact that as the PFPE material migrates toward the first surface, the claimed properties of hydrophilicity and F atom concentration are met. However, it is unclear what happens after a sufficient time has passed. However, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to continue manufacturing of the entire head, after the bonding process, such that the liquid ejection head manufacturing is completed within one day. Selecting a desired manufacturing timeframe would have required only routine skill in the art. Within this first day, it is understood from Tokuno that the PFPE film has not yet fully migrated to the first surface, thereby meeting the claimed properties. Response to Arguments Applicant's arguments have been fully considered but they are not persuasive. Regarding Kimura, Applicant argues: The liquid ejection head in Kimura has a flow path that extends from a common liquid chamber 10 through a supply opening 9 formed in the vibration plate member 2 to individual liquid chambers 6, which communice with a nozzle 4 (Kimura, Figs. 1-2). That is, the common liquid chamber 10 in Kimura merely constitutes a common flow path for liquid flowing into the individual chambers, culminating in the nozzle 4. In contrast, in accordance with the claimed invention, a liquid supply port is in correspondence with each of the liquid ejection ports, and each dedicated flow path connecting one liquid supply port and one corresponding liquid ejection port includes a portion extending in a direction parallel to the first surface and the second surface. This is neither disclosed nor suggested in Kimura. As stated in the specification "the flow path configuration may include branch flow paths extending to branch off from each of a plurality of ejection ports ... and a substrate having a flow path configuration that makes it difficult to remove a liquid repellent film using ions in plasma treatment is suitable as a target to which the present invention is applied (paragraph [0020]). Kimura does not disclose or suggest such a flow path configuration. Clearly, Kimura is different from and does not anticipate or render unpatentable the claimed invention. The examiner respectfully submits Kimura discloses the claimed flow path. Kimura discloses a plurality of liquid ejection ports (4; see [0051]) that open on the second surface, a liquid supply port (9; see [0051]) that opens on the first surface in correspondence with each of the liquid ejection ports, a flow path (5 with 6 and 7 and 8) that connects the liquid supply port and a liquid ejection port to each other (see Fig. 2) such that the liquid supply port and the liquid ejection port do not linearly communicate with each other in a direction intersecting with the first surface and the second surface (see Fig. 1), wherein each dedicated flow path connects one liquid supply port and one corresponding liquid ejection port includes a portion (e.g. 6, 7 in Fig. 1) extending in a direction parallel to the first surface and the second surface, wherein the supply port and the liquid ejection port do not overlap each other when viewed in a direction perpendicular to the first surface and the second surface (this is evident from Fig. 1). Regarding Tokuno, Applicant argues: Tokuno provides no teaching or suggestion regarding the surface treatment of the inner walls of the flow paths after substrate bonding. Clearly, this reference would not have guided a person to a configuration in which plasma generated through the completed flow paths hydrophilizes the inner surface of the ejection port while leaving a portion of the PFPE-based liquid repellent film remaining inside the ejection port. The examiner respectfully submits the claims are product claims, not process claims. Whether or not Tokuno teaches surface treatment of the inner walls of the flow path after the substrate bonding is not relevant to the present claims, as the process limitations newly added to claim 1 do not appear to result in any structural differences. Conclusion THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a). A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action. Any inquiry concerning this communication or earlier communications from the examiner should be directed to LIVIUS R CAZAN whose telephone number is (571)272-8032. The examiner can normally be reached Monday - Friday noon-8:30 pm ET. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Thomas Hong can be reached at 571-272-0993. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /LIVIUS R. CAZAN/Primary Examiner, Art Unit 3729 1 See Fig. 4. The number of liquid repellent groups decreases toward the liquid chamber side, and a static contact angle θ of the liquid on the liquid-repellent film 32a decreases continuously from the droplet ejection side to the liquid chamber side, i.e. the number of hydrophilic groups per unit area in the liquid-repellent film 32a increases continuously from the droplet ejection side to the liquid chamber side. (see [0069] and [0070]). 2 The language in italics is a process limitation. However, the claims are product claims. Product-by-process claims are not limited to the manipulations of the recited steps, only the structure implied by the steps. The process limitation in italics is not deemed to differentiate the structure of the claimed liquid ejection head from that of the prior art. Both the claimed liquid ejection head and the prior art results in the film formed inside the liquid ejection port being more hydrophilic than the perfluoropolyether liquid repellent film. 3 Tokuno removes liquid-repellent film 4 from the surfaces opposite the droplet ejection surface, to obtain a structure as shown in Fig. 17. Because PFPE film migrates toward the liquid chamber, Tokuno teaches bonding the nozzle plate 2 to a plate 35 within the first day after the removal process, to avoid the PFPE film reaching the bonding surface. See [0016] and [0091]. It is readily apparent that the migrating portion of the PFPE film becomes thinner, in a direction away from the nozzle opening. Therefore, it is inherent that this film has a higher hydrophilicity than the film 4 on the second surface (as mentioned by Kimura, the higher the number of liquid-repellent groups, the larger the contact angle; see Kimura [0111]). Since the migrating portion of the film necessarily becomes thinner in a direction away from the second surface, the contact angle decrease, i.e. hydrophilicity increases. See the further obviousness rationale for further details. 4 The language in italics is a process limitation. However, the claims are product claims. Product-by-process claims are not limited to the manipulations of the recited steps, only the structure implied by the steps. The process limitation in italics is not deemed to differentiate the structure of the claimed liquid ejection head from that of the prior art. Both the claimed liquid ejection head and the prior art results in the film formed inside the liquid ejection port being more hydrophilic than the perfluoropolyether liquid repellent film.
Read full office action

Prosecution Timeline

Feb 22, 2023
Application Filed
Nov 07, 2025
Non-Final Rejection — §102, §103
Feb 26, 2026
Response Filed
Mar 15, 2026
Final Rejection — §102, §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12550268
METHOD FOR MANUFACTURING CIRCUIT WIRING BY THREE-DIMENSIONAL ADDITIVE MANUFACTURING
2y 5m to grant Granted Feb 10, 2026
Patent 12528254
METHOD FOR MANUFACTURING A 3D ELECTROMECHANICAL COMPONENT HAVING AT LEAST ONE EMBEDDED ELECTRICAL CONDUCTOR
2y 5m to grant Granted Jan 20, 2026
Patent 12506458
PACKAGING MODULE AND PACKAGING METHOD OF BAW RESONATOR
2y 5m to grant Granted Dec 23, 2025
Patent 12501551
Method for Embedding a Component in a Printed Circuit Board
2y 5m to grant Granted Dec 16, 2025
Patent 12500494
METHOD FOR HARDENING A BRIDGE ASSEMBLY OF A ROTATIONAL BODY
2y 5m to grant Granted Dec 16, 2025
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

3-4
Expected OA Rounds
62%
Grant Probability
88%
With Interview (+25.4%)
3y 7m
Median Time to Grant
Moderate
PTA Risk
Based on 940 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month