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 .
Response to Amendment
This action is responsive to the amendments filed 03/25/2026. Claims 1-27, 29-31 are pending in this application. As directed, claims 1, 4-5, 8-10 have been amended; claim 28 cancelled; claims 11-27, 29-30 have been withdrawn; claim 31 has been newly added.
With respect to Drawings Objections: Applicant’s amendments to the Claims have overcome the Drawings Objections set forth in the Non-Final Office Action dated 12/31/2025.
With respect to Specification Objections: Applicant’s amendments to the Specification have overcome the Specification Objections set forth in the Non-Final Office Action dated 12/31/2025.
With respect to Claim Objections: Applicant’s amendments to the Claims have overcome the Claim Objections set forth in the Non-Final Office Action dated 12/31/2025, except for the limitation “the drops” recited in claim 10, see details in the Claim Objections section below. Additionally, Applicant’s amendments to the Claims filed on 03/25/2026 have created another Claim Objections, see details in the Claim Objections section below.
Response to Arguments
With respect to 35 U.S.C. 102 & 103 Claim Rejections:
Applicant(s)’ arguments filed 03/25/2026 have been fully considered but are moot based on new ground(s) of rejection necessitated by amendments. Specifically, the newly cited reference Hemmert is applied to teach the newly added limitations “wherein the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated” as recited in the independent claim 1 (lines 12-15). See detailed rejections in the 35 U.S.C. 103 Claim Rejections section below.
Claim Objections
Claims 4-5, 10 and 31 are objected to because of the following informalities:
Claim 4 recites the limitation “a previously deposited layer of the 3D object” in lines 2-3. Since claim 4 depends on claim 1, it is understood that the limitation “a previously deposited layer of the 3D object” recited in claim 4 (lines 2-3) refers to the limitation “a previously-deposited layer of the 3D object” recited in previously in claim 1 (line 13). Therefore, the limitation “a previously deposited layer of the 3D object” recited in claim 4 (lines 2-3) should be changed to “the previously-deposited layer of the 3D object” to properly refer to the corresponding limitation recited previously in claim 1 (line 13).
Claim 5 is objected by virtue of its dependence on claim 4.
Claim 10 recites the limitation “the drops” in line 2. This should be changed to “the plurality of drops” to properly refer to the corresponding limitation recited previously in claim 1 (line 3).
Claim 31 recites the limitation “an oxide layer” in line 1. Since claim 31 depends directly on claim 1, it is understood that the limitation “an oxide layer” recited in claim 31 (line 1) refers to the limitation “an oxide layer” recited in previously in claim 1 (line 13). Therefore, the limitation “an oxide layer” recited in claim 31 (line 1) should be changed to “the oxide layer” to properly refer to the corresponding limitation recited previously in claim 1 (line 13).
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 31 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 31 recites the limitation “wherein removing an oxide layer from the 3D object and heating the 3D object are performed simultaneously” in lines 1-2. This limitation was not described in the specification. Specifically, claim 31 depends directly on claim 1; claim 1 recites “wherein the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated.” in lines 12-15. However, the specification and the drawings of the Instant Application do not describe the electron positive (EP) mode (i.e., the removing oxide layer from the 3D object) and the electron negative (EN) mode (i.e., the heating the 3D object) are performed simultaneously. The specification describes: “The plasma system 150 (e.g., the power source 210) may operate in an electron positive (EP) mode and/or an electron negative (EN) mode. In the EP mode, a plurality of ions (e.g., argon ions) may contact the previously-deposited (e.g., top) layer of the 3D object 126 to remove (e.g., ablate) the oxide layer thereon. In the EN mode, the previously-deposited (e.g., top) layer of the 3D object 126 may be heated (e.g., to be from about 800 °C to about 1800 °C).” in Par.0042. However, there is no disclosure in the specification or in the drawings indicating that removing the oxide layer from the 3D object and heating the 3D object are performed simultaneously. Therefore, claim 31 contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 31 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 31 recites the limitation “wherein removing an oxide layer from the 3D object and heating the 3D object are performed simultaneously” in lines 1-2. It is unclear what is meant by this limitation because it is unclear how removing oxide layer from the 3D object and heating the 3D object can be performed simultaneously. Specifically, claim 31 depends directly on claim 1; claim 1 recites “wherein the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated.” in lines 12-15. Thus, it is unclear how the electron positive (EP) mode (i.e., the removing oxide layer from the 3D object) and the electron negative (EN) mode (i.e., the heating the 3D object) can be performed simultaneously. It is noted that alternating electrical current (AC) operates by alternating polarity, so opposite states (e.g., EP and EN) occur sequentially, not simultaneously. Furthermore, since the specification and the drawings of the Instant Application do not describe/explain the electron positive (EP) mode (i.e., the removing oxide layer from the 3D object) and the electron negative mode (EN) mode (i.e., the heating the 3D object) are performed simultaneously, it is unclear how the electron positive (EP) mode (i.e., the removing oxide layer from the 3D object) and the electron negative (EN) mode (i.e., the heating the 3D object) can be performed simultaneously.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 6-9, 31 are rejected under 35 U.S.C. 103 as being unpatentable over Sweeney et al. (U.S. Pub. No. 2020/0298479 A1; previously cited) in view of Hemmert (NPL, “The GTAW top 10: How to identify and remedy common GTAW mistakes”, Published: 07/01/2009, see attachment; newly cited).
Regarding claim 1, Sweeney discloses a 3D printing system (3D printing system 200a, Sweeney Fig.4 & Pars.0042-0043), comprising:
an ejector (ejector includes the nozzle housing 132 and the nozzle body 120, Sweeney Fig.2) (it is noted that the 3D printing system 200a as shown in Sweeney Fig.4 comprises the nozzle housing 132 and the nozzle body 120 of the extrusion nozzle 104a as shown in Sweeney Fig.2 because Sweeney Fig.4 & Par.0042 discloses the 3D printing system 200a includes a 3D printer 206, and Sweeney Par.0043 discloses: “The 3D printer 206 includes a 3D printer nozzle head, such as the extrusion nozzles 104 a, 104 b shown in FIGS. 2 and 3”) configured to receive a build material (material 102, Sweeney Fig.2), wherein the ejector (ejector includes the nozzle housing 132 and the nozzle body 120, Sweeney Fig.2) comprises a nozzle (nozzle body 120, Sweeney Fig.2), and wherein the ejector (ejector includes the nozzle housing 132 and the nozzle body 120, Sweeney Fig.2) is configured to eject a plurality of drops of the build material (material 102, Sweeney Fig.2) through the nozzle (nozzle body 120, Sweeney Fig.2) (Sweeney Par.0004 discloses: “Layers of composite material are successively deposited in droplets or continuous beads until the final 3D model has been printed”, and Sweeney Par.0038 discloses: “Referring to both FIG. 1 and FIG. 2, the extrusion nozzle 104 a is configured to heat the thermoplastic filament 102 to a molten state and extrude the molten thermoplastic material 102 in successive layers onto the platform bed 110 until the 3D part has been printed.”; therefore, Sweeney discloses the ejector configured to eject a plurality of drops of the material 102 through the nozzle body 120);
a substrate (platform bed 110, Sweeney Fig.1) positioned below the nozzle (nozzle body 120, Sweeney Fig.2) (Sweeney Par.0038 discloses: “Referring to both FIG. 1 and FIG. 2, the extrusion nozzle 104 a is configured to heat the thermoplastic filament 102 to a molten state and extrude the molten thermoplastic material 102 in successive layers onto the platform bed 110 until the 3D part has been printed.”), wherein the plurality of drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038) fall toward the substrate (platform bed 110, Sweeney Fig.1) after being ejected from the nozzle (nozzle body 120, Sweeney Fig.2) (Sweeney Par.0038 discloses: “Referring to both FIG. 1 and FIG. 2, the extrusion nozzle 104 a is configured to heat the thermoplastic filament 102 to a molten state and extrude the molten thermoplastic material 102 in successive layers onto the platform bed 110 until the 3D part has been printed.”), and wherein the plurality of drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038) form a 3D object (“3D part”, Sweeney Par.0038) on the substrate (platform bed 110, Sweeney Fig.1) (Sweeney Par.0038 discloses: “Referring to both FIG. 1 and FIG. 2, the extrusion nozzle 104 a is configured to heat the thermoplastic filament 102 to a molten state and extrude the molten thermoplastic material 102 in successive layers onto the platform bed 110 until the 3D part has been printed.”);
a power source (high voltage supply 212, Sweeney Fig.4) configured to generate an alternating electrical current (Sweeney Par.0042 discloses: “a high voltage supply 212, which could may include a direct current (DC) source, pulsed DC source, or alternating current (AC) source”; therefore, the high voltage supply 212 configured to generate an alternating electrical current); and
an electrode (electrodes 140 & 142, Sweeney Fig.2) configured to generate a plasma in response to receiving the alternating electrical current (alternating electrical current generated from the high voltage supply 212, Sweeney Fig.4 & Par.0042) (Sweeney Par.0043 discloses: “The 3D printer 206 includes a 3D printer nozzle head, such as the extrusion nozzles 104 a, 104 b shown in FIGS. 2 and 3, configured to allow a high voltage potential to be applied directly to the nozzle body, to an electrode near the print head, or to a collar surrounding the nozzles. This high voltage potential will excite either a distributed plasma cloud or a focused plasma stream directed at the 3D printed parts.”; therefore, Sweeney discloses electrodes 140 & 142 configured to generate plasma in response to receiving the alternating electrical current generated from the high voltage supply 212), wherein the plurality of drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038), the 3D object (“3D part”, Sweeney Par.0038), the substrate (platform bed 110, Sweeney Fig.1), or a combination thereof are positioned at least partially within the plasma (plasma is generated in response to receiving the alternating electrical current generated from the high voltage supply 212, as cited and explained previously) (It is noted that the limitation “the drops, the 3D object, the substrate, or a combination thereof” is in alternative form; therefore, only one of these was required during examination. In this case, Sweeney discloses the 3D object is positioned at least partially within the plasma because Sweeney Par.0043 discloses the focused plasma stream directed at the 3D printed parts; specifically, Sweeney Par.0043 discloses: “The 3D printer 206 includes a 3D printer nozzle head, such as the extrusion nozzles 104 a, 104 b shown in FIGS. 2 and 3, configured to allow a high voltage potential to be applied directly to the nozzle body, to an electrode near the print head, or to a collar surrounding the nozzles. This high voltage potential will excite either a distributed plasma cloud or a focused plasma stream directed at the 3D printed parts.”).
Sweeney does not explicitly disclose:
wherein the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated.
Hemmert teaches an alternating electrical current used in additive manufacturing:
wherein the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated (Hemmert on page 2 paragraph 6 teaches the alternating electrical current (AC) “allows the electrode positive (EP) portion of the cycle to blast away the aluminum oxide while the electrode negative (EN) portion melts the base metal.”. It is noted that in EP mode, workpiece is negative, positive ions are accelerated toward the workpiece, this is the well-known cathodic cleaning effect involving ion bombardment of the surface. Therefore, by adding the Hemmert’s teaching to the system of Sweeney, in combination, Sweeney in view of Hemmert teaches the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the system of Sweeney, by adding the teachings of the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the object and remove an oxide layer from the object, and an electron negative (EN) mode in which the previously-deposited layer of the object is heated, as taught by Hemmert, in order to clean/active surface, ensure direct material-to-material contact, provide more controlled and effective heating at the interface and avoid overheating surrounding regions to produce stronger material bonding. Thus, increase interlayer bond strength, and improve both surface condition and thermal fusion. This leads to higher adhesion strength and reduce delamination. Therefore, improve the overall print quality.
Regarding claim 6, Sweeney in view of Hemmert teach the apparatus set forth in claim 1, and also teaches:
wherein the plasma removes an oxide from the 3D object (Sweeney in view of Hemmert teach the plasma removes an oxide from the 3D object because Sweeney discloses electrode configured to generate plasma in response to receiving the alternating electrical current, and Sweeney in view of Hemmert teaches the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object; as cited, explained, and incorporated in the rejection of claim 1 above).
Regarding claim 7, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, Sweeney also discloses:
wherein the 3D printing system (3D printing system 200a [Sweeney Fig.4 & Pars.0042-0043] having the nozzle housing 132 and the nozzle body 120 [Sweeney Fig.2], as cited and explained in the rejection of claim 1 above) does not comprise an enclosure around the ejector (ejector includes the nozzle housing 132 and the nozzle body 120, Sweeney Fig.2) and the substrate (platform bed 110, Sweeney Fig.1) (there is no enclosure around the nozzle housing 132, the nozzle body 120, and the platform bed 110, see Sweeney Figs.1-2, 4).
Regarding claim 8, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, Sweeney also discloses:
wherein the ejector (ejector includes the nozzle housing 132 and the nozzle body 120, Sweeney Fig.2), the substrate (platform bed 110, Sweeney Fig.1), the drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038), and the 3D object (“3D part”, Sweeney Par.0038) are not in a vacuum environment when the plurality of drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038) are ejected from the nozzle (nozzle body 120, Sweeney Fig.2) (there is no vacuum environment; therefore, the nozzle housing 132 and the nozzle body 120, the platform bed 110, the drops formed from heating the thermoplastic filament 102 to molten state, and the 3D part are not in a vacuum environment when the drops are ejected from the nozzle body 120).
Regarding claim 9, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, Sweeney also discloses:
wherein the substrate (platform bed 110, Sweeney Fig.1) does not introduce heat into the 3D object (“3D part”, Sweeney Par.0038) when the plurality of drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038) are ejected from the nozzle (nozzle body 120, Sweeney Fig.2) (the Sweeney platform bed 110 does not introduce heat into the 3D part when the drops are ejected from the nozzle body 120).
Regarding claim 31, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, and as best understood, Sweeney in view of Hemmert teaches:
wherein removing an oxide layer from the 3D object and heating the 3D object are performed simultaneously (See the 35 U.S.C. 112 Claim Rejections section above for the 112(a) & 112(b) rejections for this claim limitation. In this case, Sweeney in view of Hemmert teaches the alternating electrical current comprises an electron positive (EP) mode in which ions contact a previously-deposited layer of the 3D object and remove an oxide layer from the 3D object, and an electron negative (EN) mode in which the previously-deposited layer of the 3D object is heated; as cited, explained and incorporated above in the rejection of claim 1. It is noted that AC current switches polarity many times per second, because the switching is very fast, the printing experiences continuous oxide cleaning and continuous heating; thus, it behaves as both effects occur at the same time).
Claims 2-3 are rejected under 35 U.S.C. 103 as being unpatentable over Sweeney et al. (U.S. Pub. No. 2020/0298479 A1; previously cited) in view of Hemmert (NPL, “The GTAW top 10: How to identify and remedy common GTAW mistakes”, Published: 07/01/2009, see attachment; newly cited), and further in view of Zhang et al. (U.S. Pub. No. 2019/0099822 A1; previously cited).
Regarding claim 2, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, but does not teach:
wherein the build material comprises a metal having a melting point greater than or equal to about 700 °C.
Zhang teaches a 3D printing system (Zhang Fig.8B):
wherein the build material (build material can be wires 26A, 26B, 30A-30D, Zhang Fig.8B & Par.0133) comprises a metal having a melting point greater than or equal to about 700 °C (Zhang Par.0090 teaches wires 30A-30D include titanium (Ti); it is noted that the melting point of titanium (Ti) is 1,668°C, according to Wikipedia [https://en.wikipedia.org/wiki/Titanium, accessed on 12/19/2025], thus, Zhang teaches the build material comprises metal having melting point greater than 700 °C).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Sweeney in view of Hemmert, by adding the teaching of build material comprising titanium, as taught by Zhang, in order to offer diverse applications for 3D parts to be printed from the 3D printing system since thermoplastic materials excelling in lightweight, rapid prototyping, consumer goods, and flexible parts due to lower cost and versatility, while metal materials provide superior strength, heat resistance, and durability for critical end-use components in aerospace, automotive, and medical fields. Furthermore, titanium has high strength-to-weight ratio, excellent corrosion resistance, high heat resistance, biocompatibility since it is non-toxic material, good material properties that enable complex designs and geometries.
Regarding claim 3, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, but does not teach:
wherein the build material comprises copper, brass, titanium, nickel, or a combination thereof.
Zhang teaches a 3D printing system (Zhang Fig.8B):
wherein the build material (build material can be wires 26A, 26B, 30A-30D, Zhang Fig.8B & Par.0133) comprises copper, brass, titanium, nickel, or a combination thereof (it is noted that the limitation “copper, brass, titanium, nickel, or a combination thereof” is in alternative form; therefore, only one of these was required during examination. In this case, Zhang Par.0090 teaches wires 30A-30D include titanium (Ti)).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Sweeney in view of Hemmert, by adding the teaching of build material comprising titanium, as taught by Zhang, in order to offer diverse applications for 3D parts to be printed from the 3D printing system since thermoplastic materials excelling in lightweight, rapid prototyping, consumer goods, and flexible parts due to lower cost and versatility, while metal materials provide superior strength, heat resistance, and durability for critical end-use components in aerospace, automotive, and medical fields. Furthermore, titanium has high strength-to-weight ratio, excellent corrosion resistance, high heat resistance, biocompatibility since it is non-toxic material, good material properties that enable complex designs and geometries.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Sweeney et al. (U.S. Pub. No. 2020/0298479 A1; previously cited) in view of Hemmert (NPL, “The GTAW top 10: How to identify and remedy common GTAW mistakes”, Published: 07/01/2009, see attachment; newly cited), and further in view of Galle (WO 2019166523 A1; previously cited).
Regarding claim 4, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, but does not explicitly teach:
wherein the plasma heats the 3D object locally to increase a temperature of a previously deposited layer of the 3D object to be from about 800 °C to about 1800 °C.
Galle teaches a 3D printing system (Galle Fig.1):
wherein the plasma (plasma jet 106 from plasma source 105, Galle Fig.1) heats the 3D object (body 103, Galle Fig.1) locally to increase a temperature of a previously deposited layer (pre-heated region 104, Galle Fig.1) of the 3D object (body 103, Galle Fig.1) to be from about 800 °C to about 1800 °C (Galle on page 15 lines 18-21 teaches: “The one or more plasma jet sources 105 provide a plasma jet 106 focused on the underlying body 103, with an energy such that the underlying material is heated close to or at the melting temperature, or even slightly above the melting temperature of the underlying material, on a target region of the underlying body, which becomes a pre-heated region 104.”, and Galle on page 24 lines 26-31 teaches: “However, the use or application of the device in accordance with embodiments of the present invention is not limited to aluminum, and it can be used to provide additive manufacturing of bodies including any other highly heat-conductive material, in particular other metals, either pure or mixed with other elements; for example it can be used with steel and steel alloys, stainless steel and alloys thereof, brass, copper, titanium, etc. Moreover, the present invention is not limited to metals. Ceramics, polymers and such can also be used”; therefore, when copper is used, the plasma jet 106 focused on the underlying body 103 with an energy such that the underlying material is heated close to or at the melting temperature of copper, which is approximately 1084.62 °C because the melting temperature of copper is 1084.62 °C, according to Wikipedia [https://en.wikipedia.org/wiki/Copper, accessed on 04/11/2026], which is within the claimed range).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Sweeney in view of Hemmert, by adding the teaching of build material comprising copper and the plasma heats the 3D object locally to increase a temperature of a top portion of the 3D object to be from about 800 °C to about 1800 °C, as taught by Galle, in order to offer diverse applications for 3D parts to be printed from the 3D printing system since thermoplastic materials excelling in lightweight, rapid prototyping, consumer goods, and flexible parts due to lower cost and versatility, while metal materials provide superior strength, heat resistance, and durability for critical end-use components in aerospace, automotive, and medical fields. In this case, copper offers exceptional thermal and electrical conductivity, good corrosion resistance, making them suitable for use in harsh or specific environments. Furthermore, locally increasing a temperature of a top portion of the 3D object to be from about 800 °C to about 1800 °C by plasma jet in order to improve layer adhesion since localized plasma heating effectively raises the temperature of the underlying layer as a new one is deposited, allowing the layers to fuse more completely, thus, this creates a stronger, more cohesive part with more uniform properties throughout. Additionally, the extremely high temperatures allow for the processing of materials that have very high melting points or require specific thermal treatment to achieve desired properties; and the plasma treatment can also be used to clean surfaces, activate materials by altering their chemical structure, and enable direct sintering processes, leading to denser, higher-quality parts.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Sweeney et al. (U.S. Pub. No. 2020/0298479 A1; previously cited) in view of Hemmert (NPL, “The GTAW top 10: How to identify and remedy common GTAW mistakes”, Published: 07/01/2009, see attachment; newly cited), Galle (WO 2019166523 A1; previously cited) and further in view of Kritchman et al. (U.S. Pub. No. 2020/0398477 A1; previously cited).
Regarding claim 5, Sweeney in view of Hemmert and Galle teaches the 3D printing system set forth in claim 4, but does not explicitly teach:
wherein a remainder of the 3D object is maintained at a temperature from about 20 °C to about 250 °C.
Kritchman teaches a 3D printing system (100, Kritchman Fig.1):
wherein a remainder (remainder is previously printed layers, see some of previously printed layers in Kritchman annotated Fig.1 below) of the 3D object (3D object, Kritchman annotated Fig.1 below) is maintained at a temperature from about 20 °C to about 250 °C (Kritchman Par.0085 teaches: “the previously printed layers may be maintained at a relatively lower temperature (e.g., about 230° C.) using cooling fan 114”; therefore, Kritchman teaches the temperature of about 230° C, which is within the claimed range).
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It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Sweeney in view of Hemmert and Galle, by adding the teaching of a remainder of the 3D object is maintained at a temperature of about 230 °C, as taught by Kritchman, in order to control cooling to ensure a more uniform temperature distribution throughout the part as it builds, which prevents distortion and improves the final component's dimensional accuracy. Extremely hot where the material needs to bond instantly and warm throughout the rest of the build to ensure the part cools slowly and evenly, resulting in a structurally sound and defect-free final product.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Sweeney et al. (U.S. Pub. No. 2020/0298479 A1; previously cited) in view of Hemmert (NPL, “The GTAW top 10: How to identify and remedy common GTAW mistakes”, Published: 07/01/2009, see attachment; newly cited), and further in view of Holverson et al. (U.S. Pub. No. 2019/0099769 A1; previously cited).
Regarding claim 10, Sweeney in view of Hemmert teaches the apparatus set forth in claim 1, Sweeney also discloses:
wherein a pressurized stream of gas including, but not limited to, argon, helium, carbon dioxide, and air is induced are introduced around the nozzle (nozzle body 120, Sweeney Fig.2), the drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038), the 3D object (“3D part”, Sweeney Par.0038), or a combination thereof when the drops (drops formed from heating the thermoplastic filament 102 to molten state, Sweeney Pars.0004 & 0038) are ejected from the nozzle (nozzle body 120, Sweeney Fig.2) (Sweeney Par.0039 discloses: “A pressurized stream of gas including, but not limited to, argon, helium, carbon dioxide, and air is induced through the plasma generation channel 134 from the inlet 136 to the outlet 138.”).
It is noted that Sweeney Par.0039 discloses: “A pressurized stream of gas including, but not limited to, argon, helium, carbon dioxide, and air is induced through the plasma generation channel 134 from the inlet 136 to the outlet 138.”. It is further noted that carbon dioxide is neither an inert gas nor a nitrogen gas. However, Sweeney is not specific enough about the carbon dioxide can be used alone as a pressurized stream of gas.
Thus, Sweeney in view of Hemmert does not explicitly teach:
wherein neither an inert gas nor a nitrogen gas is introduced around the nozzle, the drops, the 3D object, or a combination thereof when the drops are ejected from the nozzle.
Holverson teaches a 3D printing system (10, Holverson Fig.1):
wherein neither an inert gas nor a nitrogen gas is introduced around the nozzle (manufacturing tool 20, Holverson Fig.1), the drops (droplets 22, Holverson Fig.1), the 3D object (part 12, Holverson Fig.1), or a combination thereof when the drops (droplets 22, Holverson Fig.1) are ejected from the nozzle (manufacturing tool 20, Holverson Fig.1) (Holverson Par.0029 teaches: “The one or more shielding gases may include, but are not limited to, argon, carbon dioxide, helium, nitrogen, hydrogen, and combinations thereof. ”; thus, Holverson teaches the carbon dioxide gas can be used alone; it is noted that the carbon dioxide gas is neither an inert gas nor a nitrogen gas)
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Sweeney in view of Hemmert, by adding the teaching of using the carbon dioxide alone, as taught by Holverson, in order to provide high ionization potential, which helps stabilize the plasma; additionally, the modification would also offer cost-effective printing process since carbon dioxide is generally cheaper than helium and argon, making it an attractive option for large-scale printing processes.
Conclusion
The following prior art(s) made of record and not relied upon is/are considered pertinent to Applicant’s disclosure.
Giesbers et al. (U.S. Pub. No. 2018/0079132 A1) discloses a method for printing a 3D printed object, the 3D printed object comprising a first type of printed material having electrically conductive properties and a second type of printed material having electrically insulating properties.
Kim et al. (U.S. Patent No. 10,513,080 B2) discloses a method of fabricating composite articles including supplying electrical current to an electrically conductive filament.
Applicant’s amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
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/THAO UYEN TRAN-LE/Examiner, Art Unit 3761 04/11/2026
/STEVEN W CRABB/Supervisory Patent Examiner, Art Unit 3761
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