DETAILED ACTION
Status of Claims
Claims 1-3, 6-10, 13, and 16-20 are pending. Of the pending claims, claims 1-3, 6-9, 13, and 16-19 are presented for examination on the merits, and claims 10 and 20 are withdrawn from examination.
Claims 1 and 3 are currently amended.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-3, 6-8, 13, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over US 5,182,170 (A) to Marcus et al. (“Marcus”) in view of US 2010/0310404 (A1) to Ackelid (“Ackelid”) and US 2008/0131479 (A1) to Weber et al. (“Weber”) and further in view of US 2015/0241062 (A1) to Harding (“Harding”).
Regarding claim 1, Marcus teaches a method for selectively sintering (3-D printing method) a layer of powder to produce a part (printout) comprising a plurality of sintered layers (printing material is sintered into a printout). Abstract; col. 1, lines 16-21; col. 3, lines 32-60.
To build the part, steps include depositing a first portion of powder (bottom layer) onto a target surface, scanning with a directed energy beam over the target surface, and sintering a first layer of the first powder portion on the target surface (printout is formed layer-by-layer beginning with a bottom layer). Col. 4, lines 35-41.
The apparatus (3-D printing device) used to sinter the layers houses an energy beam, and a laser can be used during the build (laser-scanning the printing material to build the printout). Abstract; col. 3, lines 34-36, 47-50; col. 4, lines 35-40. The apparatus comprises a control mechanism including a computer, e.g., CAD/CAM system, to determine the defined boundaries for each layer, and given the overall dimensions and configuration of the part, the computer determines the defined boundaries for each layer and operates the laser control mechanism in accordance with the defined boundaries (printing material scanned according to a 3-D printing model, laser scanning applied to a local area of the printout). Col. 3, lines 54-68; col. 4, lines 56-68; col. 5, lines 1-2.
The selective sintering can be subjected to a gas phase reactant that interacts with the powder material, with the interaction including nitridation, oxidation, or carburization (nitrides, oxides, and carbides being ceramic phases that would contribute to increasing the hardness of a layer) (feeding a treatment gas into a 3-D printing device, the treatment gas reacts with a surface of the local area of the printout such that a hardened layer is formed). Col. 5, lines 41-51; col. 10, lines 56-65; col. 11, lines 16-26.
Marcus teaches that the selection of the powder material and of the reactive gases allows for the formation of parts of single materials, composite materials, or a graded blend of materials in the layer. Col. 5, lines 51-55. The graded blend means that each layer or portion of the layer need not be uniform in composition or have been uniformly reacted with reactive gas, suggesting that feeding the treatment gas occurs when needed.
Marcus does not explicitly teach performing scanning and feeding gas phase reactant alternately as claimed.
Ackelid is directed to an apparatus and method for producing a three-dimensional object layer by layer using powdery material by irradiating it with an energy beam. Abstract. The method includes a step of supplying a reactive gas (treatment gas) that reacts chemically and/or physically with the powder material. Abstract; para. [0005]. The reactive gas can have a hardening effect. Para. [0007], [0023]. The gas flow may be turned on and off in a controlled manner in order to harden the object (form a hardened layer by feeding treatment gas) or retain the toughness of the bulk material (forming a material layer by discontinuing supply of treatment gas into the 3-D printing device). Para. [0007]. The reactive gas can be fed into the chamber in an intermittent manner. Para. [0020].
The type of gas in the chamber depends on the desired reaction, and inert gases are not regarded as reactive. Para. [0035]. This suggests that inert gas would be selected and fed into the chamber when no reaction is desired (feed protective gas into the 3-D printing device when forming material layer by laser scanning the printing material).
Weber is directed to methods of making medical devices. Para. [0001]. The device structure is made of alternating layers by direct metal laser sintering and laser excimer nitriding. Para. [0010], [0048]. Nitrogen can influence the mechanical properties in some metals according to its proportion. Para. [0048]. In the layer-by-layer build-up, a sequence can be made of alternating layers having nitride content with layers having no nitride content (forming the hardened layer and forming the material layer alternately). Para. [0065].
It would have been obvious to one of ordinary skill in the art to have performed the scanning and gas phase reactant feeding of Marcus in the intermittent and alternating pattern taught by Ackelid and Weber because the sequence permits the user to fabricate a composite having varied and customized mechanical properties according to predetermined specifications for a particular in-service use.
Reactive gas can be used to adjust the content of carbon, nitrogen, and oxygen in the solidified metallic material, which in turn influences the tensile properties and hardness of the material. Ackelid at para. [0023]. Nitriding content and concentration can be adjusted based on gas pressure and the duration of the laser exposure, and nitriding depth depends on the length of the diffusion process. Weber at para. [0060]-[0062]; FIG. 4. Weber teaches that the layers of the multi-layer structure, which can comprise alternating nitrided/no nitrided layers, can have different thicknesses. Para. [0065]-[0067]. It therefore follows that the surface hardness of the built object can be modified (adjusted) based on the relative proportion of reactive gas and inert gas and exposure thereto (amounts and transport time) as well as the depth attained by the atoms in the reactive gas that have infiltrated the consolidated powder layer (thicknesses of the material and hardened layers).
Marcus, Ackelid, and Weber do not explicitly mention an internal elastic modulus of the object.
Harding is directed to a method of manufacturing a combustion chamber wall. Para. [0001]. The wall can be made by additive layer manufacturing, such as by using a laser beam to melt, fuse, or sinter metal powder. Para. [0042], [0097], [0100]. To improve the mechanical properties of the combustion chamber, the overall thickness of the wall or the walls of the polyhedron-shaped chambers can be increased in order to increase its strength and stiffness (corresponds to elastic modulus). Para. [0123].
As noted above in Marcus, Ackelid, and Weber, the material layer that has been exposed to reactive gas increases in hardness and forms the hardened layer. Weber teaches a multi-layer structure where the layers have different thicknesses and which can comprise alternating nitrided/no nitrided layers. Para. [0065]-[0067]. By varying the thicknesses of the hardened and/or unhardened layers, the stiffness of each layer would differ from one another due to differences in physical dimension and chemical makeup among the layers, thereby resulting in an object having a varied stiffness based on the thicknesses selected for each layer.
It would have been obvious to one of ordinary skill in the art to have adjusted the relative thickness of the hardened and material layers, as well as the amounts and time of reactive and inert gas necessary to achieve those thicknesses, in the object built by the method of Marcus in view of Ackelid and Weber because the adjustment permits the user to tailor the elastic modulus of the object to align with desired performance. For example, increasing the thickness or proportion of the hardened layers would produce a stiffer object, and decreasing the thickness or proportion of hardened layers (while increasing the proportion of non-hardened layers) would produce a more pliable object.
With respect to the relative volume ratio between material layers and hardened layers, Weber teaches that the material thicknesses of the layers can be different. Para. [0065]. Since volume depends on a thickness dimension and the thicknesses of the layers can be different (varied), the relative volumes of each layer are also different. As discussed above, increasing or decreasing (i.e., adjusting) the thicknesses/depths of the hardened layers relative to the thicknesses of the non-hardened layers (material layer) affects both hardness and stiffness (elastic modulus) of each layer. It therefore follows that adjusting the volume proportions of the hardened and non-hardened layers would result in an adjustment of the hardness and stiffness.
Regarding claim 2, Marcus teaches that the reactive gases (treatment gases) include nitrogen, oxygen, methane, and combinations and mixtures thereof (col. 11, lines 4-15), but does not explicitly identify ammonia.
In Ackelid, an example reactive gas is ammonia (NH3), which is useful for increasing the content of nitrogen in the solidified metal. Para. [0006], [0010], [0027]. Nitrogen (N2) also does the same in terms of increasing nitrogen content in a solidified metal. Para. [0028]. Nitrogen can harden the surface of a steel component. Para. [0007].
It would have been obvious to one of ordinary skill in the art to have used ammonia with or as a replacement of the nitrogen reactive gas of Marcus because ammonia is a reactive gas that would deposit nitrogen and achieve the nitriding embodiment of Marcus.
Additionally, it is prima facie obvious to combine equivalents or substitute known equivalents used for the same purpose. See MPEP § 2144.06(I)-(II). In the present instance, Ackelid teaches that ammonia and nitrogen are both reactive gases useful for nitriding metal and creating hardened layers, as noted above. Therefore, their interchangeability would be obvious because they would achieve the same goal of nitriding surfaces.
Regarding claim 3, Weber teaches that the structure can comprise layers alternating between nitrided and no nitrided layers (performing the hardened layer and the forming layer alternately until the printout is formed with space hardened layers). Para. [0065]. Since reactive gas can be used to adjust the hardness of the material (Ackelid at para. [0023]), the layered structure of Weber would result in an object having an expected hardness.
Regarding claims 6, 13, and 16, Marcus shows the laser beam (64) being applied to a local section of powder layer (local laser-scanning). FIGS. 1 and 2.
Regarding claims 7, 8, 17, and 18, Marcus teaches using an inert gas to displace undesired gas. Col. 8, lines 8-10. An example of an inert gas that normally is not regarded as reactive is argon. Ackelid at para. [0055]. It would have been obvious to one of ordinary skill in the art to have supplied an inert (non-reactive) gas during laser scanning in order to produce a structure comprising portions where gas reaction is not wanted or desired.
Claims 9 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Marcus in view of Ackelid, Weber, and Harding, as applied to claims 1 and 2 above, respectively, and further in view of US 2014/0035205 (A1) to Hagiwara et al. (“Hagiwara”).
Regarding claims 9 and 19, Marcus does not teach feeding powder (printing material) from the printing device into a recovery cylinder to recover the printing material.
Hagiwara is directed to a rapid prototyping apparatus and powder rapid prototyping method. Title; abstract. The apparatus can be used during the selective irradiation of laser light or electron beam or other energy beam on a thin layer of powder material to thereby sinter or melt and then solidify the thin layer, subsequently laminating the thin layers which have been sintered or melting and then solidified in multiple layers. Para. [0002].
The build process includes providing powder material (35) from a second feed table (34ba) onto the part table (33a), which is lowered by an amount equivalent by one layer. Para. [0086]; FIG. 4K. Residual powder material is swept to the left by the recoater (36) and carried to the first powder material housing container (32a) (recovery cylinder for recovering printing material) and housed on the first feed table (34aa). Para. [0087]; FIG. 4L. Recycling efficiency of the powder material residual after modeling can be increased. Para. [0104], [0129].
It would have been obvious to one of ordinary skill in the art to have attached a collection container to the apparatus of Marcus because it would facilitate the reclamation of unconsolidated build material, thereby decreasing waste and promoting reuse, which would lower overall manufacturing costs by not needing to purchase more material than needed.
Response to Arguments
Applicant's arguments filed 11/05/2025 have been fully considered, but they are not persuasive.
Applicant argues that neither Harding nor Weber discloses adjusting an internal elastic modulus by adjusting a volume ratio between alternating layers. Applicant states that Harding is completely silent on adjusting strength and stiffness of the walls by adjusting a ratio of thickness between layers. Applicant further argues that Weber does not teach the concept of an object having varied stiffness based on thicknesses of each layer is not taught by Weber. Applicant additionally states that Weber is completely silent on adjusting a ratio of layers of the multi-layer structure or controlling an elastic modulus of the multi-layer structure by adjusting a ratio of the layers of the multi-layer structure.
In response, the argument is not persuasive because it does not take into account the teachings of the art cited as a whole and the knowledge of a person of ordinary skill in the art. In the process of Marcus and Ackelid, the three-dimensional manufacturing method is capable of producing a non-uniform material (e.g., composite, graded) by controlling the flow of the reactive gas (Marcus at col. 5, lines 51-55; Ackelid at para. [0007]). By adjusting the reactive gas, one can adjust the content of carbon, nitrogen, and oxygen (which influence tensile, hardness, and elongation) in the material (Ackelid at para. [0023]).
One can selectively choose which fabrication areas, such as certain powder layers or certain parts of the powder layer, are contacted with reactive gas so that the chemical composition of the object can be varied geometrically (Ackelid at para. [0034]). In the instance where the flow of reactive gas is turned on and off (Ackelid at para. [0020], [0034]), the layer exposed to reactive gas and the layer not exposed to reactive gas would each possess different properties due to the different chemical compositions induced by the presence and absence of hardening atoms (carbon, nitrogen, and oxygen) in the respective layers.
Producing a non-uniform material having different nitrided (hardened) depths (thickness and therefore volume) and non-nitrided (non-hardened) layers is illustrated in Weber (FIG. 5A and 5B; para. [0065]-[0068]). In a multi-layer structure, the layers may have the same thickness as one another or different thicknesses (Weber at para. [0067]). In this instance, a nitrided layer having a thickness that differs from a non-nitrided layer results in a structure in which the relative volume between hardened and non-hardened layer differs. Stiffness (correlates to elastic modulus) is positively proportional to thickness of a given material (Harding at para. [0123]). Thus, by changing the relative thickness (and therefore the relative volumes) of a layer exposed to reactive gas and a layer not exposed to reactive gas, one is implicitly changing (adjusting) the relative internal elastic modulus and surface hardness of the different material layers.
Applicant argues that the motivation in the Office action relies on hindsight reasoning.
In response to Applicant's argument that the Examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See MPEP 2145(X)(A), citing In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). The focus when making a determination of obviousness should be on what a person of ordinary skill in the pertinent art would have known at the relevant time, and on what such a person would have reasonably expected to have been able to do in view of that knowledge. This is so regardless of whether the source of that knowledge and ability was documentary prior art, general knowledge in the art, or common sense. MPEP § 2141(II). Prior art is not limited just to the references being applied, but includes the understanding of one of ordinary skill in the art. MPEP § 2141(III).
As noted above, the creation of a non-uniform material possessing non-uniform chemical composition and non-uniform properties is well documented in the cited art. The lack of uniformity among and/or between layers leads to non-uniformity among properties due to the varied chemical composition. Layer thicknesses and diffusion depths of reactive agent (and therefore relative volumes of hardened and non-hardened layers) in a multi-layered structure need not be identical or uniform because there may be a need to produce an object possessing different mechanical properties at or in different regions of the object (e.g., Ackelid at para. [0034]; Weber at FIGS. 5A-5B, para. [0065]-[0068]). Therefore, the rejection rationale does not rely on Applicant’s own specification but rather on the disclosures of the prior art documents as well as what is reasonably implied in those disclosures.
Conclusion
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to VANESSA T. LUK whose telephone number is (571)270-3587. The examiner can normally be reached Monday-Friday 9:30 AM - 4:30 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, Keith D. Hendricks, can be reached at 571-272-1401. 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.
/VANESSA T. LUK/Primary Examiner, Art Unit 1733
February 12, 2026